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Sample records for range hopping picture

  1. The mesoscopic conductance of disordered rings, its random matrix theory and the generalized variable range hopping picture

    Energy Technology Data Exchange (ETDEWEB)

    Stotland, Alexander; Peer, Tal; Cohen, Doron [Department of Physics, Ben-Gurion University, Beer-Sheva 84005 (Israel); Budoyo, Rangga; Kottos, Tsampikos [Department of Physics, Wesleyan University, Middletown, CT 06459 (United States)

    2008-07-11

    The calculation of the conductance of disordered rings requires a theory that goes beyond the Kubo-Drude formulation. Assuming 'mesoscopic' circumstances the analysis of the electro-driven transitions shows similarities with a percolation problem in energy space. We argue that the texture and the sparsity of the perturbation matrix dictate the value of the conductance, and study its dependence on the disorder strength, ranging from the ballistic to the Anderson localization regime. An improved sparse random matrix model is introduced to capture the essential ingredients of the problem, and leads to a generalized variable range hopping picture. (fast track communication)

  2. Hops

    Science.gov (United States)

    ... the skin for leg ulcers and as an antibacterial agent. In foods and beverages, the extracts and ... that applying 1-2 grams of a vaginal gel that contains hops, hyaluronic acid, liposomes, and vitamin ...

  3. Shielding and localization in the presence of long-range hopping

    Science.gov (United States)

    Celardo, G. L.; Kaiser, R.; Borgonovi, F.

    2016-10-01

    We investigate a paradigmatic model for quantum transport with both nearest-neighbor and infinite-range hopping coupling (independent of the position). Due to long-range homogeneous hopping, a gap between the ground state and the excited states can be induced, which is mathematically equivalent to the superconducting gap. In the gapped regime, the dynamics within the excited-state subspace is shielded from long-range hopping, namely it occurs as if long-range hopping would be absent. This is a cooperative phenomenon since shielding is effective over a time scale that diverges with the system size. We named this effect cooperative shielding. We also discuss the consequences of our findings on Anderson localization. Long-range hopping is usually thought to destroy localization due to the fact that it induces an infinite number of resonances. Contrary to this common lore we show that the excited states display strong localized features when shielding is effective even in the regime of strong long-range coupling. A brief discussion on the extension of our results to generic power-law decaying long-range hopping is also given. Our preliminary results confirm that the effects found for the infinite-range case are generic.

  4. Localization in the Anderson model with long-range correlated hopping and on-site disorders

    Science.gov (United States)

    Lotfallahzadeh, Shiva; Anvari, Mehrnaz; Ekhtiary, Niko; Esmailpour, Ayoub; Rahimi Tabar, M. Reza

    2015-01-01

    We study the metal-insulator transition in one-dimensional Anderson binary alloy with long-range disordered hopping integrals and on-site energies using the transfer matrix method. In this model, the on-site energies and hopping integrals are distributed randomly with long-range correlations characterized by power spectrum of the type ?, with different exponents ? and ?, respectively. We determine the critical value of long-range correlation exponent of hopping integral ? in the presence of only off-diagonal disorder in which the transition from localized to extended states occurs in thermodynamic limit. When both of the on-site energies and hopping integrals are disordered, there are two parameters ? and ? that control the metal-insulator transition in the system. We draw the phase diagram which separates the localized regime from extended one and it shows the critical values of ? for a given value of ?.

  5. Giant magnetoresistance in the variable-range hopping regime

    Energy Technology Data Exchange (ETDEWEB)

    Ioffe, L. B., E-mail: ioffe@physics.rutgers.edu [Universite Pierre et Marie Curie, LPTHE (France); Spivak, B. Z. [University of Washington, Department of Physics (United States)

    2013-09-15

    We predict the universal power-law dependence of the localization length on the magnetic field in the strongly localized regime. This effect is due to the orbital quantum interference. Physically, this dependence shows up in an anomalously large negative magnetoresistance in the hopping regime. The reason for the universality is that the problem of the electron tunneling in a random media belongs to the same universality class as the directed polymer problem even in the case of wave functions of random sign. We present numerical simulations that prove this conjecture. We discuss the existing experiments that show anomalously large magnetoresistance. We also discuss the role of localized spins in real materials and the spin polarizing effect of the magnetic field.

  6. On the Range of Validity of the Dipole Picture

    CERN Document Server

    Ewerz, Carlo; Nachtmann, Otto

    2007-01-01

    We derive correlated bounds on ratios of deep inelastic structure functions from the dipole picture of photon-hadron scattering at high energies. In particular we consider ratios of the longitudinal structure function, the total structure function and the charm part of the latter. We also consider ratios of total structure functions taken at the same energy but at three different photon virtualities. It is shown that by confronting these bounds with experimental data we can significantly constrain the range of validity of the dipole picture.

  7. Thermally assisted variable range hopping in Tl4S3Se crystal

    Indian Academy of Sciences (India)

    Abdelhalim M Ziqan; A F Qasrawi; Abdulftah H Mohammad; N M Gasanly

    2015-06-01

    In this study, a modified model for the application of the thermionic and hopping current conduction mechanisms in the presence of continuous mixed conduction is investigated, discussed, experimented and simulated. It is observed that there exists a contribution from the hopping conductivity to the total conduction even at temperature ranges where the thermionic emission is mainly dominant. The contribution weight of a specific mechanism at particular temperature range is estimated. In addition, a modification to the Mott’s variable range hopping (VRH) transport parameters like density of localized state near the Fermi level, the average hopping range and the hopping energy in the presence of mixed conduction mechanism is also reported. This new approach corrects the evaluated electrical parameters that are necessary for the construction of electronic devices like absorption layers in solar cells. This proposed model is also used to explain the conduction mechanism and investigate the electrical conduction thermionic and Mott’s VRH parameters in Tl4S3Se crystals and in CuAlO2 thin films.

  8. Application of time-hopping UWB range-bit rate performance in the UWB sensor networks

    NARCIS (Netherlands)

    Nascimento, J.R.V. do; Nikookar, H.

    2008-01-01

    In this paper, the achievable range-bit rate performance is evaluated for Time-Hopping (TH) UWB networks complying with the FCC outdoor emission limits in the presence of Multiple Access Interference (MAI). Application of TH-UWB range-bit rate performance is presented for UWB sensor networks. Result

  9. Hopping Time Scales and the Phonon-Liquid Electron-Crystal Picture in Thermoelectric Copper Selenide

    Science.gov (United States)

    Voneshen, D. J.; Walker, H. C.; Refson, K.; Goff, J. P.

    2017-04-01

    The suppression of transverse phonons by liquidlike diffusion in superionic conductors has been proposed as a means to dramatically reduce thermal conductivity in thermoelectric materials [H. Lui et al. Nat. Mater. 11, 422 (2012), 10.1038/nmat3273]. We have measured the ion transport and lattice dynamics in the original phonon-liquid electron-crystal Cu2Se using neutron spectroscopy. We show that hopping time scales are too slow to significantly affect lattice vibrations and that the transverse phonons persist at all temperatures. Substantial changes to the phonon spectrum occur well below the transition to the superionic phase, and the ultralow thermal conductivity is instead attributed to anharmonicity.

  10. Size effect on high temperature variable range hopping in Al+ implanted 4H-SiC

    Science.gov (United States)

    Parisini, Antonella; Parisini, Andrea; Nipoti, Roberta

    2017-01-01

    The hole transport properties of heavily doped 4H-SiC (Al) layers with Al implanted concentrations of 3  ×  1020 and 5  ×  1020 cm-3 and annealed in the temperature range 1950-2100 °C, have been analyzed to determine the main transport mechanisms. This study shows that the temperature dependence of the resistivity (conductivity) may be accounted for by a variable range hopping (VRH) transport into an impurity band. Depending on the concentration of the implanted impurities and the post-implantation annealing treatment, this VRH mechanism persists over different temperature ranges that may extend up to room temperature. In this framework, two different transport regimes are identified, having the characteristic of an isotropic 3D VRH and an anisotropic nearly 2D VRH. The latter conduction mechanism appears to take place in a rather thick layer (about 400 nm) that is too large to induce a confinement effect of the carrier hops. The possibility that an anisotropic transport may be induced by a structural modification of the implanted layer because of a high density of basal plane stacking faults (SF) in the implanted layers is considered. The interpretation of the conduction in the heaviest doped samples in terms of nearly 2D VRH is supported by the results of the transmission electron microscopy (TEM) investigation on one of the 5  ×  1020 cm-3 Al implanted samples of this study. In this context, the average separation between basal plane SFs, measured along the c-axis, which is orthogonal to the carrier transport during electrical characterization, appears to be in keeping with the estimated value of the optimal hopping length of the VRH theory. Conversely, no SFs are detected by TEM in a sample with an Al concentration of 1  ×  1019 cm-3 where a 3D nearest neighbor hopping (NNH) transport is observed.

  11. Variable-Range Hopping Conductivity in Quantum Hall Regime for HgTe-Based Heterostructure

    Science.gov (United States)

    Arapov, Yu. G.; Gudina, S. V.; Neverov, V. N.; Podgornykh, S. M.; Popov, M. R.; Harus, G. I.; Shelushinina, N. G.; Yakunin, M. V.; Dvoretsky, S. A.; Mikhailov, N. N.

    2016-12-01

    We have measured the longitudinal and Hall resistivities in the quantum Hall regime at magnetic fields B up to 9 T and temperatures T =(2.9div 50) K for the HgCdTe/HgTe/HgCdTe heterostructure with a wide HgTe quantum well. The temperature-induced transport at the resistivity minima corresponding to the quantum Hall plateaus has been studied within the concept of hopping conduction in a strongly localized electron system. An analysis of the variable-range hopping conductivity in the regions of the first and second quantum Hall plateaus provided an opportunity to determine the value and the magnetic-field dependence of the localization length with the experimental estimation of the critical indices.

  12. PT symmetry breaking in the presence of random, periodic, long-range hopping

    Science.gov (United States)

    Harter, Andrew K.; Onanga, Franck Assogba; Joglekar, Yogesh N.

    2016-09-01

    Over the past five years, open systems with balanced gain and loss have been investigated for extraordinary properties that are not shared by their closed counterparts. Non-Hermitian, Parity-Time (PT ) symmetric Hamiltonians faithfully model such systems. Such a Hamiltonian typically consists of a reflection-symmetric, Hermitian, nearest-neighbor hopping profile and a PT-symmetric, non-Hermitian, gain and loss potential, and has a robust PT -symmetric phase. Here we investigate the robustness of this phase in the presence of long-range hopping disorder that is not PT-symmetric, but is periodic. We find that the PT-symmetric phase remains robust in the presence of such disorder, and characterize the configurations where that happens. Our results are found using a tight-binding model, and we validate our predictions through the beam-propagation method.

  13. Surface hopping outperforms secular Redfield theory when reorganization energies range from small to moderate (and nuclei are classical)

    Energy Technology Data Exchange (ETDEWEB)

    Landry, Brian R., E-mail: landrybr@gmail.com; Subotnik, Joseph E. [Department of Chemistry, University of Pennsylvania, 231 S. 34th Street, Philadelphia, Pennsylvania 19104 (United States)

    2015-03-14

    We evaluate the accuracy of Tully’s surface hopping algorithm for the spin-boson model in the limit of small to moderate reorganization energy. We calculate transition rates between diabatic surfaces in the exciton basis and compare against exact results from the hierarchical equations of motion; we also compare against approximate rates from the secular Redfield equation and Ehrenfest dynamics. We show that decoherence-corrected surface hopping performs very well in this regime, agreeing with secular Redfield theory for very weak system-bath coupling and outperforming secular Redfield theory for moderate system-bath coupling. Surface hopping can also be extended beyond the Markovian limits of standard Redfield theory. Given previous work [B. R. Landry and J. E. Subotnik, J. Chem. Phys. 137, 22A513 (2012)] that establishes the accuracy of decoherence-corrected surface-hopping in the Marcus regime, this work suggests that surface hopping may well have a very wide range of applicability.

  14. Variable range hopping conduction and microstructure properties of semiconducting Co-doped TiO 2

    Science.gov (United States)

    Okutan, Mustafa; Bakan, Halil I.; Korkmaz, Kemal; Yakuphanoglu, Fahrettin

    2005-01-01

    The surface morphology, phases existing in the microstructure and conductivity behavior of Co-doped TiO2 have been investigated by atomic force microscopy (AFM), scanning electron microscopy (SEM), electrical conductivity measurements and X-ray diffraction technique. The semiconducting phase is found to obey Mott's variable range hopping mechanism of the conduction. The conduction mechanism of the ceramic shows a crossover from the, exp[-(T0/T)] law to a simply activated law, exp(-ΔE/kT). This behavior is attributed to temperature-induced transition from 3D to thermally activated behavior. The hopping conduction parameters such as the characteristic temperature ( T0), localization length ( α), hopping distance ( R), activation energy ( ΔE) and density of states at Fermi level (N(EF) have been calculated. Surface morphology shows that the ceramic has a regular surface. The SEM study indicates that there are grains which have a certain type in the microstructure. Rutile phases with different plane in microstructure were found.

  15. Scaling of current distributions in variable-range hopping transport on two- and three-dimensional lattices

    Science.gov (United States)

    Pasveer, W. F.; Bobbert, P. A.; Huinink, H. P.; Michels, M. A. J.

    2005-11-01

    From extensive computer simulations of variable-range hopping (VRH) transport of charges on regular two- and three-dimensional lattices with random site energies we calculate the average contribution to the total current of hops over a certain distance and with a certain hop energy. We find that the resulting current distribution is a universal function of scaled distance and energy variables. We discuss this scaling in the light of the original arguments of Mott and percolation arguments to explain the temperature dependence of the VRH conductivity.

  16. Apparent Power Law Scaling of Variable Range Hopping Conduction in Carbonized Polymer Nanofibers

    Science.gov (United States)

    Kim, Kyung Ho; Lara-Avila, Samuel; Kang, Hojin; He, Hans; Eklӧf, Johnas; Hong, Sung Ju; Park, Min; Moth-Poulsen, Kasper; Matsushita, Satoshi; Akagi, Kazuo; Kubatkin, Sergey; Park, Yung Woo

    2016-11-01

    We induce dramatic changes in the structure of conducting polymer nanofibers by carbonization at 800 °C and compare charge transport properties between carbonized and pristine nanofibers. Despite the profound structural differences, both types of systems display power law dependence of current with voltage and temperature, and all measurements can be scaled into a single universal curve. We analyze our experimental data in the framework of variable range hopping and argue that this mechanism can explain transport properties of pristine polymer nanofibers as well.

  17. Variable range hopping and nonlinear transport in monolayer epitaxial graphene grown on SiC

    Science.gov (United States)

    Liu, Chieh-I.; Wu, Bi-Yi; Chuang, Chiashain; Lee, Ya-Chi; Ho, Yi-Ju; Yang, Yanfei; Elmquist, Randolph E.; Lo, Shun-Tsung; Liang, Chi-Te

    2016-10-01

    We report experimental results on variable range hopping (VRH) and nonlinear transport in monolayer epitaxial graphene. In the linear regime in which the conductance is independent of voltage, the resistance curve derivative analysis method can be used to unequivocally determine whether Mott VRH or Efros-Shklovskii VRH is the dominant transport mechanism in our devices. In the nonlinear regime in which the conductance shows a strong dependence on voltage, we find that our experimental results can be successfully described by existing theoretical models. We suggest that the observed vastly different exponents in the threshold voltage-temperature dependence require further experimental and theoretical studies.

  18. Conductance distribution at criticality: one-dimensional Anderson model with random long-range hopping

    Energy Technology Data Exchange (ETDEWEB)

    Mendez, A. [Instituto de Fisica, Universidad Autonoma de Puebla, Apartado Postal J-48, Puebla 72570 (Mexico); Gopar, V. [Departamento de Fisica Teorica and Instituto de Biocomputacion y Fisica de Sistemas Complejos (BIFI), Universidad de Zaragoza, Pedro Cerbuna 12, 50009 Zaragoza (Spain); Varga, I. [Elmeleti Fizika Tanszek, Fizikai Intezet, Budapesti Mueszaki es Gazdasagtudomanyi Egyetem, 1521 Budapest (Hungary); Fachbereich Physik und Wissenschaftliches Zentrum fuer Materialwissenschaften, Philipps Universitaet Marburg, 35032 Marburg (Germany)

    2009-12-15

    We study numerically the conductance distribution function w(T) for the one-dimensional Anderson model with random long-range hopping described by the Power-law Banded Random Matrix model at criticality. We concentrate on the case of two single-channel leads attached to the system. We observe a smooth transition from localized to delocalized behavior in the conductance distribution by increasing b, the effective bandwidth of the model. Also, for b < 1 we show that w(ln T/T{sub typ}) is scale invariant, where T{sub typ} = exp left angle ln T right angle is the typical value of T. Moreover, we find that for T < T{sub typ}, w(ln T/T{sub typ}) shows a universal behavior proportional to (T/T{sub typ}){sup -1/2}. (Abstract Copyright [2009], Wiley Periodicals, Inc.)

  19. Robust unidirectional transport in a one-dimensional metacrystal with long-range hopping

    CERN Document Server

    Longhi, Stefano

    2016-01-01

    In two- and three-dimensional structures, topologically-protected chiral edge modes offer a powerful mean to realize robust light transport. However, little attention has been paid so far to robust one-way transport in one-dimensional systems. Here it is shown that unidirectional transport, which is immune to disorder and backscattering, can occur in certain one-dimensional metacrystals with long-range hopping without resorting to topological protection. Such metacrystals are described by an effective Hermitian Hamiltonian with broken time reversal symmetry, and transport does not require adiabatic (Thouless) pumping. A simple implementation in optics of such one-dimensional metacrystals, based on transverse light dynamics in a self-imaging optical cavity with phase gratings, is suggested

  20. Variable range hopping crossover and magnetotransport in PLD grown Sb doped ZnO thin film

    Science.gov (United States)

    Mukherjee, Joynarayan; Mannam, Ramanjaneyulu; Ramachandra Rao, M. S.

    2017-04-01

    We report on the variable range hopping (VRH) crossover in the electrical transport of Sb doped ZnO (SZO) thin film. Structural, chemical, electrical and magnetotransport properties were carried out on SZO thin film grown by pulsed laser deposition. X-photoelectron spectroscopy study confirms the presence of both Sb3+(33%) and Sb5+(67%) states. Sb doped ZnO thin film shows n-type behavior which is attributed to the formation of SbZn and/or SbZn–VZn defect complex. Temperature dependent resistivity measurement showed that in a low temperature regime (doped ZnO thin films is explained by the Khosla and Fischer model.

  1. Structure and conductivity of clusters generated by variable-range hopping percolation

    Science.gov (United States)

    Huinink, H. P.; Bobbert, P. A.; Pasveer, W. F.; Michels, M. A. J.

    2006-06-01

    An important class of models for variable-range hopping (VRH) transport processes of electrons in highly disordered systems is based on percolation arguments. In these models the so-called critical path analysis (CPA) is combined with percolation arguments based on standard percolation models. Despite the increased computer power in the last decade there have been little attempts to validate the applicability of standard percolation theory on VRH problems. We have performed systematic numerical calculations on the structure and conductivity of VRH percolation clusters in two dimensions. It is shown by analyzing the mass of the clusters and the correlation length that VRH percolation clusters indeed behave as standard percolation clusters. The main difference between VRH percolation and standard percolation seems to be the existence of a temperature dependent effective lattice constant. Conductivity calculations on VRH clusters have been performed that support the central idea behind CPA models. Furthermore, these calculations confirm the existence of critical subnetworks.

  2. Transport Properties of the Organic Conductor (TMTSF)2BrO4: Evidence of Variable Range Hopping

    DEFF Research Database (Denmark)

    Mortensen, Kell; Jacobsen, Claus Schelde; Bechgaard, Klaus

    1984-01-01

    A study of d.c. and microwave conductivity and thermoelectric power of the organic conductor (TMTSF)2BrO4 is presented. The transport properties are in qualitative agreement with charge transport via variable-range hopping among localized states. The localization is attributed to the anions, which...

  3. One-dimensional variable range hopping conduction in a single crystal of La 2CuO 4+y

    Science.gov (United States)

    Corraze, B.; Ribault, M.

    1993-02-01

    We have measured the resistivity perpendicular to the CuO 2 planes, in the magnetically ordered phases of a single crystal of La 2CuO 4+y as a function of temperature. Within a limited temperature range a one-dimensional variable range hopping conduction mechanism is identified, in zero magnetic field. The analysis of both the temperature range and the magnetic field variation shows that this mechanism is strongly dependent on the intraplane and on the interplane couplings.

  4. Coulomb gap and variable-range hopping in self-organized carbon networks

    Science.gov (United States)

    Govor, L. V.; Bashmakov, I. A.; Boehme, K.; Pientka, M.; Parisi, J.

    2001-08-01

    Carbon networks fabricated by means of a self-organized process, which is in the focus of our interest, represent disordered porous systems. The degree of disorder and, accordingly, the values of their electric conductivity extending from insulator to metal behavior change via heat treatment under vacuum conditions at process temperatures in the range from 600 to 1000 °C. Upon varying the ambient temperature from 4.2 to 295 K, four transport mechanisms can be observed. For carbon nets whose conductivity is far beyond the metal-insulator transition (MIT), the specific resistivity ρ depends on the temperature T as ρ(T)∝T-b exp([T0/T]1/p). In the low-temperature range, a Coulomb gap in the density of states located near the Fermi energy level occurs, which means that the characteristic value of the exponent is p=2. At high temperatures, the pre-exponential part ρ(T)∝T-b dominates. In the intermediate temperature range, we disclose Mott's hopping law with p=3. However, the specific resistivity of the carbon networks subject close to the MIT follows the power law ρ(T)∝T-b with 0≲b≲3 at low temperatures. In the high-temperature range, the specific resistivity is characterized by ρ(T)∝exp(-[T/T1]c-1), where the values for c vary from 1.3 to 1.5. The above four charge transport mechanisms can be explained by the tails in the density of localized states pulled out of the conduction and valence band, as a consequence of disorder and, particularly, by some overlap between these tails.

  5. Variable-range hopping conduction and metal-insulator transition in amorphous RexSi1-x thin films

    Science.gov (United States)

    Lisunov, K. G.; Vinzelberg, H.; Arushanov, E.; Schumann, J.

    2011-09-01

    Resistivity, ρ(T), of the amorphous RexSi1-x thin films with x = 0.285-0.351 is investigated in the interval of T ~ 300-0.03 K. At x = 0.285-0.324 the activated behavior of ρ(T) is governed by the Mott and the Shklovskii-Efros variable-range hopping (VRH) conduction mechanisms in different temperature intervals and the three-dimensional regime of the hopping. Between x = 0.328 and 0.351 the activationless dependence of ρ(T) takes place. The critical behavior of the characteristic VRH temperatures and of the Coulomb gap, Δ, pertinent to proximity to the metal-insulator transition at the critical value of xc ≈ 0.327, is observed. The analysis of the critical behavior of Δ yields directly the critical exponent of the dielectric permittivity, η = 2.1 ± 0.2, in agreement with the theoretical prediction, η = 2. On the other hand, the values of the critical exponent of the correlation length ν ~ 0.8-1.1 close to the expected value of unity can be obtained from the analysis of the critical behavior of the VRH characteristic temperatures under an additional assumption of a strong underbarrier scattering of hopping charge carriers in conditions, when the concentration of scattering centers considerably exceeds the concentration of sites involved in the hopping.

  6. Numerical studies of variable-range hopping in one-dimensional systems

    Science.gov (United States)

    Rodin, A. S.; Fogler, M. M.

    2010-03-01

    We report on our recent numerical study [1] of hopping transport in disordered one-dimensional systems. A fast new algorithm, based on Dijkstra shortest-path algorithm, is devised to find the lowest-resistance path through the hopping network at arbitrary electric field. Probability distribution functions of individual resistances on the path and the net resistance are calculated and fitted to compact analytic formulas. Qualitative differences between statistics of resistance fluctuations in Ohmic and non-Ohmic regimes are elucidated. The results are compared with prior theoretical and experimental work on the subject.[6pt] [1] A. S. Rodin and M. M. Fogler, Phys. Rev. B 80, 155435 (2009).

  7. Ferromagnetism, variable range hopping, and the anomalous Hall effect in epitaxial Co:ZnO thin film

    Institute of Scientific and Technical Information of China (English)

    Bai Hong-Liang; Chen Yan-Xue; Mei Liang-Mo; He Shu-Min; Xu Tong-Shuai; Liu Guo-Lei; Yan Shi-Shen; Zhu Da-Peng; Dai Zheng-Kun; Yang Feng-Fan; Dai You-Yong

    2012-01-01

    A series of high quality single crystalline epitaxial Zn0.95Co0.05O thin films is prepared by molecular beam epitaxy.Superparamagnetism and ferromagnetism are observed when the donor density is manipulated in a range of 1018 cm-3- 1020 cm-3 by changing the oxygen partial pressure during film growth.The conduction shows variable range hopping at low temperature and thermal activation conduction at high temperature.The ferromagnetism can be maintained up to room temperature.However,the anomalous Hall effect is observed only at low temperature and disappears above 160 K.This phenomenon can be attributed to the local ferromagnetism and the decreased optimal hopping distance at high temperatures.

  8. Variable range hopping conduction and microstructure properties of semiconducting Co-doped TiO{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Okutan, Mustafa [Department of Physics, Gebze Institute of Technology, 41400 Gebze (Turkey)]. E-mail: mokutan@gyte.edu.tr; Bakan, Halil I. [TUBITAK-MAM, Materials and Chemical Research Institute, 41470 Gebze (Turkey); Korkmaz, Kemal [Department of Material Science and Engineering, Gebze Institute of Technology, 41400 Gebze (Turkey); Yakuphanoglu, Fahrettin [Department of Physics, Faculty of Arts and Science, Firat University, 23169 Elazig (Turkey)

    2005-01-31

    The surface morphology, phases existing in the microstructure and conductivity behavior of Co-doped TiO2 have been investigated by atomic force microscopy (AFM), scanning electron microscopy (SEM), electrical conductivity measurements and X-ray diffraction technique. The semiconducting phase is found to obey Mott's variable range hopping mechanism of the conduction. The conduction mechanism of the ceramic shows a crossover from the, exp[-(T0/T)1/4] law to a simply activated law, exp(-{delta}E/kT). This behavior is attributed to temperature-induced transition from 3D to thermally activated behavior. The hopping conduction parameters such as the characteristic temperature (T0), localization length ({alpha}), hopping distance (R), activation energy ({delta}E) and density of states at Fermi level (N(EF) have been calculated. Surface morphology shows that the ceramic has a regular surface. The SEM study indicates that there are grains which have a certain type in the microstructure. Rutile phases with different plane in microstructure were found.

  9. Anderson transition in low-dimensional disordered systems driven by long-range nonrandom hopping.

    Science.gov (United States)

    Rodríguez, A; Malyshev, V A; Sierra, G; Martín-Delgado, M A; Rodríguez-Laguna, J; Domínguez-Adame, F

    2003-01-17

    The single-parameter scaling hypothesis predicts the absence of delocalized states for noninteracting quasiparticles in low-dimensional disordered systems. We show analytically, using a supersymmetric method combined with a renormalization group analysis, as well as numerically that extended states may occur in the one- and two-dimensional Anderson model with a nonrandom hopping falling off as some power of the distance between sites. The different size scaling of the bare level spacing and the renormalized magnitude of the disorder seen by the quasiparticles finally results in the delocalization of states at one of the band edges of the quasiparticle energy spectrum.

  10. Solvent-mediated electron hopping: long-range charge transfer in IBr-(CO2) photodissociation.

    Science.gov (United States)

    Sheps, Leonid; Miller, Elisa M; Horvath, Samantha; Thompson, Matthew A; Parson, Robert; McCoy, Anne B; Lineberger, W Carl

    2010-04-09

    Chemical bond breaking involves coupled electronic and nuclear dynamics that can take place on multiple electronic surfaces. Here we report a time-resolved experimental and theoretical investigation of nonadiabatic dynamics during photodissociation of a complex of iodine monobromide anion with carbon dioxide [IBr-(CO2)] on the second excited (A') electronic state. Previous experimental work showed that the dissociation of bare IBr- yields only I- + Br products. However, in IBr-(CO2), time-resolved photoelectron spectroscopy reveals that a subset of the dissociating molecules undergoes an electron transfer from iodine to bromine 350 femtoseconds after the initial excitation. Ab initio calculations and molecular dynamics simulations elucidate the mechanism for this charge hop and highlight the crucial role of the carbon dioxide molecule. The charge transfer between two recoiling atoms, assisted by a single solvent-like molecule, provides a notable limiting case of solvent-driven electron transfer over a distance of 7 angstroms.

  11. Efros-Shklovskii type variable range hopping conduction and magnetoresistance in p-type CuGa3Te5

    Science.gov (United States)

    Wasim, S. M.; Essaleh, L.; Marín, G.; Rincón, C.; Amhil, S.; Galibert, J.

    2017-07-01

    Variable range hopping conduction of Efros and Shklovskii type when a Coulomb gap appears at the Fermi level due to repulsive interaction of the holes, is observed in two different temperature regions in the ordered defect compound CuGa3Te5. Since this type of electrical conduction appears over a very wide temperature range between 4 and 150 K, not reported before in elemental II-VI, and I-III-VI2 compound semiconductors, three different methods were employed to analyze the data to confirm this behavior. This is also supported from the study of the variation of impurity band hole mobility with temperature. Other hopping parameters are estimated. The logarithmic variation of the positive magnetoresistance at different temperatures in the two regions varies as B2 and B1/5 above and below the critical field Bc, that separates the low and high magnetic field regions. This is in complete agreement with the theory of Efros and Shklovskii. The temperature dependence of the corresponding slope as T- 3/2 and T- 3/5 is also consistent with the proposed models.

  12. Impact Of Mobility and Transmission Range On The Performance of Backoff Algorithms For IEEE 802.11-Based Multi-hop Mobile Ad hoc Networks

    CERN Document Server

    Saini, Pooja

    2010-01-01

    In IEEE 802.11 Wireless Local Area Networks (WLANs), network nodes experiencing collisions on the shared channel need to backoff for a random period of time, which is uniformly selected from the Contention Window (CW). This contention window is dynamically controlled by the Backoff algorithm. First step to design a an efficient backoff algorithm for multi-hop ad hoc network is to analysis of the existing backoff algorithms in multi-hop ad hoc networks. Thus, in this paper, we considered two important multi-hop adhoc network scenarios: (a) Node Mobility Scenario and (b) Transmission Range Scenario and analyze and evaluate both the impact of mobility (i.e. node speed) and the impact of transmission range of nodes on the performance of various backoff algorithms

  13. Wheeled hopping robot

    Science.gov (United States)

    Fischer, Gary J [Albuquerque, NM

    2010-08-17

    The present invention provides robotic vehicles having wheeled and hopping mobilities that are capable of traversing (e.g. by hopping over) obstacles that are large in size relative to the robot and, are capable of operation in unpredictable terrain over long range. The present invention further provides combustion powered linear actuators, which can include latching mechanisms to facilitate pressurized fueling of the actuators, as can be used to provide wheeled vehicles with a hopping mobility.

  14. Investigation of hopped frequency waveforms for range and velocity measurements of radar targets

    CSIR Research Space (South Africa)

    Kathree, U

    2015-10-01

    Full Text Available In the field of radar, High Range Resolution (HRR) profiles are often used to improve target tracking accuracy in range and to allow the radar system to produce an image of an object using techniques such as inverse synthetic aperture radar (ISAR...

  15. Poole-Frenkel effect and variable-range hopping conduction in metal/YBCO resistive switching devices

    Science.gov (United States)

    Schulman, A.; Lanosa, L. F.; Acha, C.

    2015-07-01

    Current-voltage (IV) characteristics and the temperature dependence of the contact resistance [R(T)] of Au/YBa2Cu3O7-δ (optimally doped YBCO) interfaces have been studied at different resistance states. These states were produced by resistive switching after accumulating cyclic electrical pulses of increasing number and voltage amplitude. The IV characteristics and the R(T) dependence of the different states are consistent with a Poole-Frenkel (P-F) emission mechanism with trapping-energy levels Et in the 0.06-0.11 eV range. Et remains constant up to a number-of-pulses-dependent critical voltage and increases linearly with a further increase in the voltage amplitude of the pulses. The observation of a P-F mechanism reveals the existence of an oxygen-depleted layer of YBCO near the interface. A simple electrical transport scenario is discussed, where the degree of disorder, the trap energy level, and the temperature range determine an electrical conduction dominated by non-linear effects, either in a P-F emission or in a variable-range hopping regime.

  16. Spin-glass and variable range hopping quantum interference magnetoresistance in FeSr2Y1.3Ce0.7Cu2O10-x

    Science.gov (United States)

    Sambale, S.; Williams, G. V. M.; Stephen, J.; Chong, S. V.

    2014-12-01

    Electronic transport and magnetic measurements have been made on FeSr2Y1.3Ce0.7Cu2O10-x. We observe a spin-glass at ˜23 K and a magnetoresistance that reaches -22% at 8 T. The magnetoresistance is due to variable range hopping quantum interference where at low temperatures each hop is over a large number of scatterers. This magnetoresistance is negative at and above 5 K and can be described by the Nguen, Spivak, and Shklovskii (NSS) model. However, there is an increasingly positive contribution to the magnetoresistance for temperatures below 5 K that may be due to scattering from localized free spins during each hop that is not accounted for in the NSS model.

  17. Variable range hopping in single-wall carbon nanotube thin films: a processing-structure-property relationship study.

    Science.gov (United States)

    Luo, Sida; Liu, Tao; Benjamin, Shermane M; Brooks, James S

    2013-07-09

    By varying the ultrasonication and ultracentrifugation conditions, single-walled carbon nanotube (SWCNT) dispersions with a broad range of SWCNT length and diameter (L = 342-3330 nm; d = 0.5-12 nm) were prepared and characterized by a preparative ultracentrifuge method (PUM) and dynamic light scattering (DLS) technique. The well-characterized dispersions were then fabricated into SWCNT thin films by spray coating. Combined optical, spectroscopic, and temperature-dependent electrical measurements were performed to study the effect of SWCNT structures on the charge transport behavior of SWCNT thin films. Regardless of SWCNT size in the dispersion and the thin film thickness, the three-dimensional variable range hopping (3D VRH) conduction model was found to be appropriate in explaining the temperature-dependent sheet resistance results for all SWCNT thin films prepared in this study. More importantly, with the SWCNT structural information determined by the PUM method, we were able to identify a strong correlation between the length of SWCNTs and the 3D VRH parameter T0, the Mott characteristic temperature. When the SWCNT length is less than ∼700 nm, the T0 of SWCNT thin films shows a drastic increase, but when the length is greater than ~700 nm, T0 is only weakly dependent on the SWCNT length. Under the framework of traditional VRH, we further conclude that the electron localization length of SWCNT thin films shows a similar dependence on the SWCNT length.

  18. The Effect of a Long-Range Correlated-Hopping Interaction on Bariev Spin Chains

    Directory of Open Access Journals (Sweden)

    Tao Yang

    2015-08-01

    Full Text Available We introduce a long-range particle and spin interaction into the standard Bariev model and show that this interaction is equivalent to a phase shift in the kinetic term of the Hamiltonian. When the particles circle around the chain and across the boundary, the accumulated phase shift acts as a twist boundary condition with respect to the normal periodic boundary condition. This boundary phase term depends on the total number of particles in the system and also the number of particles in different spin states, which relates to the spin fluctuations in the system. The model is solved exactly via a unitary transformation by the coordinate Bethe ansatz. We calculate the Bethe equations and work out the energy spectrum with varying number of particles and spins.

  19. Insulator-to-metal transition in vanadium supersaturated silicon: variable-range hopping and Kondo effect signatures

    Science.gov (United States)

    García-Hemme, E.; Montero, D.; García-Hernansanz, R.; Olea, J.; Mártil, I.; González-Díaz, G.

    2016-07-01

    We report the observation of the insulator-to-metal transition in crystalline silicon samples supersaturated with vanadium. Ion implantation followed by pulsed laser melting and rapid resolidification produce high quality single-crystalline silicon samples with vanadium concentrations that exceed equilibrium values in more than 5 orders of magnitude. Temperature-dependent analysis of the conductivity and Hall mobility values for temperatures from 10 K to 300 K indicate that a transition from an insulating to a metallic phase is obtained at a vanadium concentration between 1.1  ×  1020 and 1.3  ×  1021 cm-3. Samples in the insulating phase present a variable-range hopping transport mechanism with a Coulomb gap at the Fermi energy level. Electron wavefunction localization length increases from 61 to 82 nm as the vanadium concentration increases in the films, supporting the theory of impurity band merging from delocalization of levels states. On the metallic phase, electronic transport present a dispersion mechanism related with the Kondo effect, suggesting the presence of local magnetic moments in the vanadium supersaturated silicon material.

  20. Circulating current in 1D Hubbard rings with long-range hopping: Comparison between exact diagonalization method and mean-field approach

    OpenAIRE

    Saha, Madhumita; Maiti, Santanu K.

    2016-01-01

    The interplay between Hubbard interaction, long-range hopping and disorder on persistent current in a mesoscopic one-dimensional conducting ring threaded by a magnetic flux $\\phi$ is analyzed in detail. Two different methods, exact numerical diagonalization and Hartree-Fock mean field theory, are used to obtain numerical results from the many-body Hamiltonian. The current in a disordered ring gets enhanced as a result of electronic correlation and it becomes more significant when contribution...

  1. Circulating current in 1D Hubbard rings with long-range hopping: Comparison between exact diagonalization method and mean-field approach

    Science.gov (United States)

    Saha, Madhumita; Maiti, Santanu K.

    2016-10-01

    The interplay between Hubbard interaction, long-range hopping and disorder on persistent current in a mesoscopic one-dimensional conducting ring threaded by a magnetic flux ϕ is analyzed in detail. Two different methods, exact numerical diagonalization and Hartree-Fock mean field theory, are used to obtain numerical results from the many-body Hamiltonian. The current in a disordered ring gets enhanced as a result of electronic correlation and it becomes more significant when contributions from higher order hoppings, even if they are too small compared to nearest-neighbor hopping, are taken into account. Certainly this can be an interesting observation in the era of long-standing controversy between theoretical and experimental results of persistent current amplitudes. Along with these we also find half-flux quantum periodic current for some typical electron fillings and kink-like structures at different magnetic fluxes apart from ϕ = 0 and ±ϕ0 / 2. The scaling behavior of current is also discussed for the sake of completeness of our present analysis.

  2. Photographer : JPL Range : 1,094,666 km (677,000 mi.) This false color picture of Callisto was taken

    Science.gov (United States)

    1979-01-01

    Photographer : JPL Range : 1,094,666 km (677,000 mi.) This false color picture of Callisto was taken by Voyager 2 and is centered on 11 degrees N and 171 degrees W. This rendition uses an ultraviolet image for the blue component. Because the surface displays regional contrast in UV, variations in surface materials are apparent. Notice in particular the dark blue haloes which surround bright craters in the eastern hemisphere. The surface of Callisto is the most heavily cratered of the Galilean satellites and resembles ancient heavily cratered terrains on the moon, Mercury and Mars. The bright areas are ejecta thrown out by relatively young impact craters. A large ringed structure, probably an impact basin, is shown in the upper left part of the picture. The color version of this picture was constructed by compositing black and white images taken through the ultraviolet, clear and orange filters.

  3. Hall effect in hopping regime

    Energy Technology Data Exchange (ETDEWEB)

    Avdonin, A., E-mail: avdonin@ifpan.edu.pl [Institute of Physics, Polish Academy of Sciences, Al. Lotników 32/46, 02-668 Warszawa (Poland); Skupiński, P. [Institute of Physics, Polish Academy of Sciences, Al. Lotników 32/46, 02-668 Warszawa (Poland); Grasza, K. [Institute of Physics, Polish Academy of Sciences, Al. Lotników 32/46, 02-668 Warszawa (Poland); Institute of Electronic Materials Technology, ul. Wólczyńska 133, 01-919 Warszawa (Poland)

    2016-02-15

    A simple description of the Hall effect in the hopping regime of conductivity in semiconductors is presented. Expressions for the Hall coefficient and Hall mobility are derived by considering averaged equilibrium electron transport in a single triangle of localization sites in a magnetic field. Dependence of the Hall coefficient is analyzed in a wide range of temperature and magnetic field values. Our theoretical result is applied to our experimental data on temperature dependence of Hall effect and Hall mobility in ZnO. - Highlights: • Expressions for Hall coefficient and mobility for hopping conductivity are derived. • Theoretical result is compared with experimental curves measured on ZnO. • Simultaneous action of free and hopping conduction channels is considered. • Non-linearity of hopping Hall coefficient is predicted.

  4. Structural, nanomechanical and variable range hopping conduction behavior of nanocrystalline carbon thin films deposited by the ambient environment assisted filtered cathodic jet carbon arc technique

    Energy Technology Data Exchange (ETDEWEB)

    Panwar, O.S., E-mail: ospanwar@mail.nplindia.ernet.in [Polymorphic Carbon Thin Films Group, Physics of Energy Harvesting Division, CSIR-National Physical Laboratory, Dr. K. S. Krishnan Road, New Delhi - 110 012 (India); Rawal, Ishpal; Tripathi, R.K. [Polymorphic Carbon Thin Films Group, Physics of Energy Harvesting Division, CSIR-National Physical Laboratory, Dr. K. S. Krishnan Road, New Delhi - 110 012 (India); Srivastava, A.K. [Electron and Ion Microscopy, Sophisticated and Analytical Instruments, CSIR-National Physical Laboratory, Dr. K. S. Krishnan Road, New Delhi - 110 012 (India); Kumar, Mahesh [Ultrafast Opto-Electronics and Tetrahertz Photonics Group, CSIR-National Physical Laboratory, Dr. K. S. Krishnan Road, New Delhi - 110 012 (India)

    2015-04-15

    Highlights: • Nanocrystalline carbon thin films are grown by filtered cathodic jet carbon arc process. • Effect of gaseous environment on the properties of carbon films has been studied. • The structural and nanomechanical properties of carbon thin films have been studied. • The VRH conduction behavior in nanocrystalline carbon thin films has been studied. - Abstract: This paper reports the deposition and characterization of nanocrystalline carbon thin films by filtered cathodic jet carbon arc technique assisted with three different gaseous environments of helium, nitrogen and hydrogen. All the films are nanocrystalline in nature as observed from the high resolution transmission electron microscopic (HRTEM) measurements, which suggests that the nanocrystallites of size ∼10–50 nm are embedded though out the amorphous matrix. X-ray photoelectron spectroscopic studies suggest that the film deposited under the nitrogen gaseous environment has the highest sp{sup 3}/sp{sup 2} ratio accompanied with the highest hardness of ∼18.34 GPa observed from the nanoindentation technique. The film deposited under the helium gaseous environment has the highest ratio of the area under the Raman D peak to G peak (A{sub D}/A{sub G}) and the highest conductivity (∼2.23 S/cm) at room temperature, whereas, the film deposited under the hydrogen environment has the lowest conductivity value (2.27 × 10{sup −7} S/cm). The temperature dependent dc conduction behavior of all the nanocrystalline carbon thin films has been analyzed in the light of Mott’s variable range hopping (VRH) conduction mechanism and observed that all the films obey three dimension VRH conduction mechanism for the charge transport.

  5. Frequency hopping millimeter wave reflectometer

    Science.gov (United States)

    Cupido, L.; Sánchez, J.; Estrada, T.

    2004-10-01

    Reflectometry techniques are employed to study density fluctuations in fusion plasmas either using one channel or two channels with slightly different frequencies, to probe simultaneously closely spaced plasma layers (for radial correlation studies). The present article describes a novel system with increasing measuring capability utilizing only one single frequency that can be hopped during the discharge. This broadband fast hopping mm-wave reflectometer (BFHR) has been developed for both ASDEX upgrade (Max Plank Institute-Garching-Germany) and TJ-II stellarator (CIEMAT-Spain). The BFHR incorporates frequency synthesizers at microwave frequencies multiplied into the millimeter-wave range and uses heterodyne detection for sensitive phase and amplitude measurements.

  6. Phase diagram of hopping conduction mechanisms in polymer nanofiber network

    Energy Technology Data Exchange (ETDEWEB)

    Li, Jeng-Ting; Lu, Yu-Cheng; Jiang, Shiau-Bin; Zhong, Yuan-Liang, E-mail: ylzhong@cycu.edu.tw [Department of Physics and Center for Nanotechnology, Chung Yuan Christian University, Chung-Li 32023, Taiwan (China); Yeh, Jui-Ming [Department of Chemistry and Center for Nanotechnology, Chung Yuan Christian University, Chung-Li 32023, Taiwan (China)

    2015-12-07

    Network formation by nanofiber crosslinking is usually in polymer materials as application in organic semiconductor devices. Electron hopping transport mechanisms depend on polymer morphology in network. Conducting polymers morphology in a random network structure is modeled by a quasi-one-dimensional system coupled of chains or fibers. We observe the varying hopping conduction mechanisms in the polyaniline nanofibers of the random network structure. The average diameter d of the nanofibers is varied from approximately 10 to 100 nm. The different dominant hopping mechanisms including Efros-Shklovskii variable-range hopping (VRH), Mott VRH, and nearest-neighbor hopping are dependent on temperature range and d in crossover changes. The result of this study is first presented in a phase diagram of hopping conduction mechanisms based on the theories of the random network model. The hopping conduction mechanism is unlike in normal semiconductor materials.

  7. Steerable Hopping Six-Legged Robot

    Science.gov (United States)

    Younse, Paulo; Aghazarian, Hrand

    2010-01-01

    The figure depicts selected aspects of a six-legged robot that moves by hopping and that can be steered in the sense that it can be launched into a hop in a controllable direction. This is a prototype of hopping robots being developed for use in scientific exploration of rough terrain on remote planets that have surface gravitation less than that of Earth. Hopping robots could also be used on Earth, albeit at diminished hopping distances associated with the greater Earth gravitation. The upper end of each leg is connected through two universal joints to an upper and a lower hexagonal frame, such that the tilt of the leg depends on the relative position of the two frames. Two non-back-driveable worm-gear motor drives are used to control the relative position of the two frames along two axes 120 apart, thereby controlling the common tilt of all six legs and thereby, further, controlling the direction of hopping. Each leg includes an upper and a lower aluminum frame segment with a joint between them. A fiberglass spring, connected via hinges to both segments, is used to store hopping energy prior to launch into a hop and to cushion the landing at the end of the hop. A cable for loading the spring is run into each leg through the center of the universal joints and then down along the center lines of the segments to the lower end of the leg. A central spool actuated by a motor with a harmonic drive and an electromagnetic clutch winds in all six cables to compress all six springs (thereby also flexing all six legs) simultaneously. To ensure that all the legs push off and land in the same direction, timing- belt pulley drives are attached to the leg segments, restricting the flexing and extension of all six legs to a common linear motion. In preparation for a hop, the spool can be driven to load the spring legs by an amount corresponding to a desired hop distance within range. The amount of compression can be computed from the reading of a shaft-angle encoder that

  8. Hopping transport in solids

    CERN Document Server

    Pollak, M

    1991-01-01

    The hopping process, which differs substantially from conventional transport processes in crystals, is the central process in the transport phenomena discussed in this book. Throughout the book the term ``hopping'' is defined as the inelastic tunneling transfer of an electron between two localized electronic states centered at different locations. Such processes do not occur in conventional electronic transport in solids, since localized states are not compatible with the translational symmetry of crystals.The rapid growth of interest in hopping transport has followed in the footsteps of the

  9. Multiphonon hopping of carriers in CuO thin films

    Science.gov (United States)

    Serin, T.; Yildiz, A.; Şahin, Ş. H.; Serin, N.

    2011-10-01

    We have performed a detailed study of the electrical conduction process in CuO thin films deposited by the sol-gel dip coating technique in a temperature range 280-420 K. The electrical conduction is analyzed within the framework of various hopping conduction models. Multiphonon hopping conduction mechanism is found to dominate the electrical transport in the entire temperature region. Our results are consistent with this model of hopping conduction mechanisms with weak carrier-lattice coupling.

  10. HIP-HOP

    Institute of Scientific and Technical Information of China (English)

    QunyKing; 人在羽中; 钱李明

    2005-01-01

    自从一群摇滚青年开始跟风 Elvis 的《Blue SuedeShoes》风格,hip-hop 似乎就成为了全球最具影响力的音乐风格。它最初起源于美国的黑人和拉丁美洲人,之后迅速在全世界流行,成为80年代、90年代和新千年的主流音乐。无论是在广告界还是在电影业,从各类排行榜到各种酒吧,hip-hop 的影响逐年增加。在1997年,英国的 hip-hop 还只是一种地下音

  11. Superconductivity from correlated hopping

    CERN Document Server

    Batista, C D; Aligia, A A

    1995-01-01

    We consider a chain described by a next-nearest-neighbor hopping combined with a nearest-neighbor spin flip. In two dimensions this three-body term arises from a mapping of the three-band Hubbard model for CuO$_2$ planes to a generalized $t-J$ model and for large O-O hopping favors resonance-valence-bond superconductivity of predominantly $d$-wave symmetry. Solving the ground state and low-energy excitations by analytical and numerical methods we find that the chain is a Luther-Emery liquid with correlation exponent $K_{\\rho} = (2-n)^2/2$, where $n$ is the particle density.

  12. First report of hop stunt viroid from sweet cherry with dapple apple fruit symptoms in China

    Science.gov (United States)

    Hop stunt viroid (HSVd), the type member of the genus Hostuviroid, family Pospiviroidae, was first described from hops with stunt disease in Japan. HSVd has a wide host range that includes hop, cucumber, citrus, grapevine, plum, pear, peach, apricot and almond and is the causal agent of serious dis...

  13. Hopping models for ion conduction in noncrystals

    DEFF Research Database (Denmark)

    Dyre, Jeppe; Schrøder, Thomas

    2007-01-01

    Ion conduction in noncrystals (glasses, polymers, etc) has a number of properties in common. In fact, from a purely phenomenological point of view, these properties are even more widely observed: ion conduction behaves much like electronic conduction in disordered materials (e.g., amorphous...... semiconductors). These universalities are subject of much current interest, for instance interpreted in the context of simple hopping models. In the present paper we first discuss the temperature dependence of the dc conductivity in hopping models and the importance of the percolation phenomenon. Next......, the experimental (quasi)universality of the ac conductivity is discussed. It is shown that hopping models are able to reproduce the experimental finding that the response obeys time-temperature superposition, while at the same time a broad range of activation energies is involved in the conduction process. Again...

  14. Picture perfect

    DEFF Research Database (Denmark)

    Pless, Mette; Sørensen, Niels Ulrik

    Picture perfect’ – when perfection becomes the new normal This paper draws on perspectives from three different studies. One study, which focuses on youth life and lack of well-being (Sørensen et al 2011), one study on youth life on the margins of society (Katznelson et al 2015) and one study on...

  15. Quantum Trajectory Approach to Molecular Dynamics Simulation with Surface Hopping

    CERN Document Server

    Feng, Wei; Li, Xin-Qi; Fang, Weihai

    2012-01-01

    The powerful molecular dynamics (MD) simulation is basically based on a picture that the atoms experience classical-like trajectories under the exertion of classical force field determined by the quantum mechanically solved electronic state. In this work we propose a quantum trajectory approach to the MD simulation with surface hopping, from an insight that an effective "observation" is actually implied in theMDsimulation through tracking the forces experienced, just like checking the meter's result in the quantum measurement process. This treatment can build the nonadiabatic surface hopping on a dynamical foundation, instead of the usual artificial and conceptually inconsistent hopping algorithms. The effects and advantages of the proposed scheme are preliminarily illustrated by a two-surface model system.

  16. Abnormal hopping conduction in semiconducting polycrystalline graphene

    Science.gov (United States)

    Park, Jeongho; Mitchel, William C.; Elhamri, Said; Grazulis, Larry; Altfeder, Igor

    2013-07-01

    We report the observation of an abnormal carrier transport phenomenon in polycrystalline semiconducting graphene grown by solid carbon source molecular beam epitaxy. At the lowest temperatures in samples with small grain size, the conduction does not obey the two-dimensional Mott-type variable-range hopping (VRH) conduction often reported in semiconducting graphene. The hopping exponent p is found to deviate from the 1/3 value expected for Mott VRH with several samples exhibiting a p=2/5 dependence. We also show that the maximum energy difference between hopping sites is larger than the activation energy for nearest-neighbor hopping, violating the assumptions of the Mott model. The 2/5 dependence more closely agrees with the quasi-one-dimensional VRH model proposed by Fogler, Teber, and Shklovskii (FTS). In the FTS model, conduction occurs by tunneling between neighboring metallic wires. We suggest that metallic edge states and conductive grain boundaries play the role of the metallic wires in the FTS model.

  17. Flexible Surface Hopping Approach to Model the Crossover from Hopping to Band-like Transport in Organic Crystals.

    Science.gov (United States)

    Wang, Linjun; Beljonne, David

    2013-06-06

    Two distinct pictures are usually evoked when modeling charge transport in organic crystals, that is, band and hopping models, the signature of which is conveyed by a characteristic temperature dependence of mobility. Here, we present a novel flexible surface hopping approach compliant with general Hamiltonians that is able to grasp the crossover from hopping to band-like transport regimes. This approach is applied to solve a one-dimensional mixed quantum-classical model and to calculate the temperature dependence of charge mobility along with the degree of charge spatial localization. It is found that the roles of both local and nonlocal electron-phonon couplings strongly depend on the intrinsic charge localization strength.

  18. Correlated hopping of bosonic atoms induced by optical lattices

    Energy Technology Data Exchange (ETDEWEB)

    Eckholt, Maria [Max-Planck-Institut fuer Quantenoptik, Hans-Kopfermann-Strasse 1, Garching, D-85478 (Germany); Garcia-Ripoll, Juan Jose [Instituto de Fisica Fundamental, CSIC, c/Serrano 113b, Madrid E-28006 (Spain)], E-mail: maria.eckholt@mpq.mpg.de

    2009-09-15

    In this work, we analyze a particular setup with ultracold atoms trapped in state-dependent lattices. We show that any asymmetry in the contact interaction translates into one of two classes of correlated hopping. After deriving the effective lattice Hamiltonian for the atoms, we obtain analytically and numerically the different phases and quantum phase transitions. We find for weak correlated hopping both Mott insulators and charge density waves, while for stronger correlated hopping the system transitions into a pair superfluid. We demonstrate that this phase exists for a wide range of interaction asymmetries and has interesting correlation properties that differentiate it from an ordinary atomic Bose-Einstein condensate.

  19. Basin Hopping Graph

    DEFF Research Database (Denmark)

    Kucharik, Marcel; Hofacker, Ivo; Stadler, Peter

    2014-01-01

    Motivation RNA folding is a complicated kinetic process. The minimum free energy structure provides only a static view of the most stable conformational state of the system. It is insufficient to give detailed insights into the dynamic behavior of RNAs. A sufficiently sophisticated analysis...... of the folding free energy landscape, however, can provide the relevant information. Results We introduce the basin hopping graph (BHG) as a novel coarse-grained model of folding landscapes. Each vertex of the BHG is a local minimum, which represents the corresponding basin in the landscape. Its edges connect...

  20. Cover Picture.

    Science.gov (United States)

    Breuning; Ruben; Lehn; Renz; Garcia; Ksenofontov; Gütlich; Wegelius; Rissanen

    2000-07-17

    The cover picture shows how both, fine arts and science, avail themselves of a system of intertwined symbolic and iconic languages. They make use of a common set of abstracted signs to report on their results. Thus, already in 1925, Wassily Kandinsky painted a masterpiece (bottom), which now, 75 years later, might be regarded as a blueprint for a scientific project. In his painting, Kandinsky pictured a grid-shaped sign that resembles in effect an actual molecular switch. Apparently following an enigmatic protocol, the groups of Lehn and Gütlich (see p. 2504 ff. for more details) constructed a grid-type inorganic architecture that operates as a three-level magnetic switch (center) triggered by three external perturbations (p, T, hnu). The switching principle is based on the spin-crossover phenomenon of Fe(II) ions and can be monitored by Mössbauer spectroscopy (left) and magnetic measurements (rear). Maybe not by chance, the English translation of the title of the painting "signs" is a homonym of "science", since both presented works are a product of the insatiable curiosity of man and his untiring desire to recognize his existence.

  1. Correlated barrier hopping of CuO nanoparticles

    Science.gov (United States)

    Koshy, Jiji; Soosen, Samuel. M.; Chandran, Anoop; George, K. C.

    2015-12-01

    The ac conduction mechanism in copper oxide nanoparticles with 8 nm size, synthesized by a precipitation method was studied by analyzing ac conductivity in the frequency range of 50 Hz-1 MHz and in the temperature range of 373-573 K. X-ray diffraction and transmission electron microscopy (TEM) were employed for the structural and morphological characterization of CuO nanoparticles. The experimental and theoretical investigations suggested that the ac conduction mechanism in CuO nanoparticles can be successfully explained by a correlated barrier hopping model, which provided reasonable values for the maximum barrier height and characteristic relaxation time. It was also found that bipolaron hopping become prominent up to a particular temperature and beyond that single polaron hopping predominates. Physical parameters such as hopping distance and density of defect states were also calculated. Photoluminescence studies confirm the presence of a surface defect in CuO nanoparticles.

  2. The impact of hop bitter acid and polyphenol profiles on the perceived bitterness of beer.

    Science.gov (United States)

    Oladokun, Olayide; Tarrega, Amparo; James, Sue; Smart, Katherine; Hort, Joanne; Cook, David

    2016-08-15

    Thirty-four commercial lager beers were analysed for their hop bitter acid, phenolic acid and polyphenol contents. Based on analytical data, it was evident that the beers had been produced using a range of different raw materials and hopping practices. Principal Components Analysis was used to select a sub-set of 10 beers that contained diverse concentrations of the analysed bitter compounds. These beers were appraised sensorially to determine the impacts of varying hop acid and polyphenolic profiles on perceived bitterness character. Beers high in polyphenol and hop acid contents were perceived as having 'harsh' and 'progressive' bitterness, whilst beers that had evidently been conventionally hopped were 'sharp' and 'instant' in their bitterness. Beers containing light-stable hop products (tetrahydro-iso-α-acids) were perceived as 'diminishing', 'rounded' and 'acidic' in bitterness. The hopping strategy adopted by brewers impacts on the nature, temporal profile and intensity of bitterness perception in beer.

  3. Effective one-dimensionality of universal ac hopping conduction in the extreme disorder limit

    DEFF Research Database (Denmark)

    Dyre, Jeppe; Schrøder, Thomas

    1996-01-01

    A phenomenological picture of ac hopping in the symmetric hopping model (regular lattice, equal site energies, random energy barriers) is proposed according to which conduction in the extreme disorder limit is dominated by essentially one-dimensional "percolation paths." Modeling a percolation path...... as strictly one dimensional with a sharp jump rate cutoff leads to an expression for the universal ac conductivity that fits computer simulations in two and three dimensions better than the effective medium approximation....

  4. Involvement of Vacuolar Sequestration and Active Transport in Tolerance of Saccharomyces cerevisiae to Hop Iso-α-Acids

    NARCIS (Netherlands)

    Hazelwood, L.A.; Walsh, M.C.; Pronk, J.T.; Daran, J.M.

    2009-01-01

    The hop plant, Humulus lupulus L., has an exceptionally high content of secondary metabolites, the hop -acids, which possess a range of beneficial properties, including antiseptic action. Studies performed on the mode of action of hop iso--acids have hitherto been restricted to lactic acid bacteria.

  5. Involvement of Vacuolar Sequestration and Active Transport in Tolerance of Saccharomyces cerevisiae to Hop Iso-α-Acids

    NARCIS (Netherlands)

    Hazelwood, L.A.; Walsh, M.C.; Pronk, J.T.; Daran, J.M.

    2009-01-01

    The hop plant, Humulus lupulus L., has an exceptionally high content of secondary metabolites, the hop -acids, which possess a range of beneficial properties, including antiseptic action. Studies performed on the mode of action of hop iso--acids have hitherto been restricted to lactic acid bacteria.

  6. Supercritical fluid extraction of hops

    Directory of Open Access Journals (Sweden)

    ZORAN ZEKOVIC

    2007-01-01

    Full Text Available Five cultivars of hop were extracted by the method of supercritical fluid extraction using carbon dioxide (SFE–CO2 as extractant. The extraction (50 g of hop sample using a CO2 flow rate of 97.725 L/h was done in the two steps: 1. extraction at 150 bar and 40°C for 2.5 h (sample of series A was obtained and, after that, the same sample of hop was extracted in the second step: 2. extraction at 300 bar and 40 °C for 2.5 h (sample of series B was obtained. The Magnum cultivar was chosen for the investigation of the extraction kinetics. For the qualitative and quantitative analysis of the obtained hop extracts, the GC-MS method was used. Two of four themost common compounds of hop aroma (a-humulene and b-caryophyllene were detected in samples of series A. In addition, isomerized a-acids and a high content of b-acids were detected. The a-acids content in the samples of series B was the highest in the extract of the Magnum cultivar (it is a bitter variety of hop. The low contents of a-acids in all the other hop samples resulted in extracts with low a-acids content, i.e., that contents were under the prescribed a-acids content.

  7. Picosecond Dynamic Heterogeneity, Hopping, and Johari-Goldstein Relaxation in Glass-Forming Liquids

    Science.gov (United States)

    Cicerone, Marcus T.; Zhong, Qin; Tyagi, Madhusudan

    2014-09-01

    We show that incoherent quasielastic neutron scattering from molecular liquids reveals a two-state dynamic heterogeneity on a 1 ps time scale, where molecules are either highly confined or are free to undergo relatively large excursions. Data ranging from deep in the glassy state to well above the melting point allows us to observe temperature-dependent population levels and exchange between these two states. A simple physical picture emerges from this data, combined with published work, that provides a mechanism for hopping and for the Johari-Goldstein (βJG) relaxation, and allows us to accurately calculate the diffusion coefficient, DT, and characteristic times for α, and βJG relaxations from ps time scale neutron data.

  8. Design on hopping locomotion mechanism

    Institute of Scientific and Technical Information of China (English)

    LU Yong-kui; WU Yue-hua; YANG Jie; Hisayuki AOYAMA

    2005-01-01

    A new type of locomotion mechanism is introduced in this paper. With vibrating motors used in controling the movement of the hopping locomotion mechanism, the simple hopping locomotion mechanism had two motors, when the current went through the vertical motor, the vertical motor would vibrate to cause the mechanism to go forward, and when the current went through the horizontal motor, the mechanism will go around itself. A spring was added to the mechanism to change the natural frequency of the mechanism, when the frequency of the motor was equal to the natural frequency of the mechanism, the mechanism would hop resonantly. With the resonant hopping, the load of the mechanism was greatly enlarged, and some sensors could be added to the mechanism. Optical sensors were used to detect the infrared source, the current that went through the sensors related to the distance between the infrared light. Three optical sensors was put on the left, right and the front the mechanism, when the mechanism detect the special infrared source, it would turn itself to the light, and go forward to the light. The experiments of the mechanism shown that the mechanism could work well on different surfaces freely, and the resonant hopping locomotion mechanism with infrared sensors could move to the special light by automatic regulation. Experimental results and theoretical studies demonstrate that the innovative design for hopping locomotion mechanism is superior.

  9. HOP expression is regulated by p53 and RAS and characteristic of a cancer gene signature.

    Science.gov (United States)

    Mattison, Stacey A; Blatch, Gregory L; Edkins, Adrienne L

    2017-03-01

    The Hsp70/Hsp90 organising protein (HOP) is a co-chaperone essential for client protein transfer from Hsp70 to Hsp90 within the Hsp90 chaperone machine. Although HOP is upregulated in various cancers, there is limited information from in vitro studies on how HOP expression is regulated in cancer. The main objective of this study was to identify the HOP promoter and investigate its activity in cancerous cells. Bioinformatic analysis of the -2500 to +16 bp region of the HOP gene identified a large CpG island and a range of putative cis-elements. Many of the cis-elements were potentially bound by transcription factors which are activated by oncogenic pathways. Luciferase reporter assays demonstrated that the upstream region of the HOP gene contains an active promoter in vitro. Truncation of this region suggested that the core HOP promoter region was -855 to +16 bp. HOP promoter activity was highest in Hs578T, HEK293T and SV40- transformed MEF1 cell lines which expressed mutant or inactive p53. In a mutant p53 background, expression of wild-type p53 led to a reduction in promoter activity, while inhibition of wild-type p53 in HeLa cells increased HOP promoter activity. Additionally, in Hs578T and HEK293T cell lines containing inactive p53, expression of HRAS increased HOP promoter activity. However, HRAS activation of the HOP promoter was inhibited by p53 overexpression. These findings suggest for the first time that HOP expression in cancer may be regulated by both RAS activation and p53 inhibition. Taken together, these data suggest that HOP may be part of the cancer gene signature induced by a combination of mutant p53 and mutated RAS that is associated with cellular transformation.

  10. Hop (Humulus lupulus)-derived bitter acids as multipotent bioactive compounds.

    Science.gov (United States)

    Van Cleemput, Marjan; Cattoor, Ko; De Bosscher, Karolien; Haegeman, Guy; De Keukeleire, Denis; Heyerick, Arne

    2009-06-01

    Hop acids, a family of bitter compounds derived from the hop plant (Humulus lupulus), have been reported to exert a wide range of effects, both in vitro and in vivo. They exhibit potential anticancer activity by inhibiting cell proliferation and angiogenesis, by inducing apoptosis, and by increasing the expression of cytochrome P450 detoxification enzymes. Furthermore, hop bitter acids are effective against inflammatory and metabolic disorders, which makes them challenging candidates for the treatment of diabetes mellitus, cardiovascular diseases, and metabolic syndrome. This review summarizes the current knowledge on hop bitter acids, including both phytochemical aspects, as well as the biological and pharmacological properties of these compounds.

  11. Generalized adiabatic polaron hopping: Meyer-Neldel compensation and Poole-Frenkel behavior.

    Science.gov (United States)

    Emin, David

    2008-04-25

    The commonly employed adiabatic treatment of polaron hopping is extended to treat the continuous alteration of a carrier wave function with the atoms' movements and a carrier's long-range interaction with a polar surrounding. These features, respectively, introduce carrier-induced softening of the atoms' vibrations and a hopping activation energy that depends on hopping distance. The Meyer-Neldel compensation effect results from carrier-induced softening of vibrations. Poole-Frenkel behavior emerges for electric-field driven polaron hopping in ionic and polar media.

  12. Supercritical carbon dioxide hop extraction

    Directory of Open Access Journals (Sweden)

    Pfaf-Šovljanski Ivana I.

    2005-01-01

    Full Text Available The hop of Magnum cultivar was extracted using supercritical carbon dioxide (SFE-as extractant. Extraction was carried out in the two steps: the first one being carried out at 150 bar and 40°C for 2.5 h (Extract A, and the second was the extraction of the same hop sample at 300 bar and 40°C for 2.5 h (Extract B. Extraction kinetics of the system hop-SFE-CO2 was investigated. Two of four most common compounds of hop aroma (α-humulene and β-caryophyllene were detected in Extract A. Isomerised α-acids and β-acids were detected too. a-Acid content in Extract B was high (that means it is a bitter variety of hop. Mathematical modeling using empirical model characteristic time model and simple single sphere model has been performed on Magnum cultivar extraction experimental results. Characteristic time model equations, best fitted experimental results. Empirical model equation, fitted results well, while simple single sphere model equation poorly approximated the results.

  13. Influence of the constituent alpha acids of Ukrainian varieties of hops and hop preparations on quality indicators of mash and beer

    Directory of Open Access Journals (Sweden)

    L. Protsenko

    2015-05-01

    Full Text Available Introduction. The aim of the study is to establish the dependence of the bitterness of mash and the beer intoxication on the quality and quantity of the homologues of alpha acids in the Ukrainian varieties of hops, and on the content of cohumulone in alpha acids in particular. Materials and methods.Aromatic and bitter hop sorts of Ukrainian selection with different content of cohumulone in alpha-acids were investigated and so was the beer, made of these components. High performance liquid chromatography (HPLC was used to determine the amount and composition of bitter hop substances and their transformation products in the brewing process; also there were spectrophotometric methods for quality control of bitterness of hopped mash and finished beer in use. Results and discussion. The composition of bitter substances of aromatic and bitter hop sorts of Ukrainian selection was analyzed and so the beer, made of them. It was noted that the alpha-acids of the analyzed sorts incorporate a wide range of cohumulone content rated from 16.7% in the Kumyr sort to 44,1% in the Ruslan sort. The dependences between the quality and quantity of the bitter hop sorts and bitterness and quality of hopped mash and beer were established. The content of cohumulone in alphaacids of hops has to be less than 28% to obtain quality bitter beer. The role of the beta-acid compoundsin the formation of bitter mash, hopped with aroma hop varieties with a ratio of beta to alpha acids acids around one, is much more important compared to the bitter varieties. Conclusions. The conducted researches show that in applying the bitter hops with different compositon of alphaacids for mash intoxication, this usage is more effective in the sorts that have a large content of cohumulone.

  14. Coarse-grained picture of Brownian motion in water: Role of size and interaction distance range on the nature of randomness.

    Science.gov (United States)

    Hanasaki, Itsuo; Nagura, Ryo; Kawano, Satoyuki

    2015-03-14

    The Brownian motion of a particle in a fluid is often described by the linear Langevin equation, in which it is assumed that the mass of the particle is sufficiently large compared to the surrounding fluid molecules. This assumption leads to a diffusion coefficient that is independent of the particle mass. The Stokes-Einstein equation indicates that the diffusion coefficient depends solely on the particle size, but the concept of size can be ambiguous when close to the molecular scale. We first examine the Brownian motion of simple model particles based on short-range interactions in water by the molecular dynamics method and show that the diffusion coefficient can vary with mass when this mass is comparable to that of the solvent molecules, and that this effect is evident when the solute particle size is sufficiently small. We then examine the properties of a water molecule considered as a solute in the bulk solvent consisting of the remainder of the water. A comparison with simple solute models is used to clarify the role of force fields. The long-range Coulomb interaction between water molecules is found to lead to a Gaussian force distribution in spite of a mass ratio and nominal size ratio of unity, such that solutes with short-range interactions exhibit non-Gaussian force distribution. Thus, the range of the interaction distance determines the effective size even if it does not represent the volume excluded by the repulsive force field.

  15. Lowest excited states and optical absorption spectra of donor–acceptor copolymers for organic photovoltaics: a new picture emerging from tuned long-range corrected density functionals

    KAUST Repository

    Pandey, Laxman

    2012-01-01

    Polymers with low optical gaps are of importance to the organic photovoltaics community due to their potential for harnessing a large portion of the solar energy spectrum. The combination along their backbones of electron-rich and electron-deficient fragments contributes to the presence of low-lying excited states that are expected to display significant charge-transfer character. While conventional hybrid functionals are known to provide unsatisfactory results for charge-transfer excitations at the time-dependent DFT level, long-range corrected (LRC) functionals have been reported to give improved descriptions in a number of systems. Here, we use such LRC functionals, considering both tuned and default range-separation parameters, to characterize the absorption spectra of low-optical-gap systems of interest. Our results indicate that tuned LRC functionals lead to simulated optical-absorption properties in good agreement with experimental data. Importantly, the lowest-lying excited states (excitons) are shown to present a much more localized nature than initially anticipated. © 2012 the Owner Societies.

  16. Lowest excited states and optical absorption spectra of donor-acceptor copolymers for organic photovoltaics: a new picture emerging from tuned long-range corrected density functionals.

    Science.gov (United States)

    Pandey, Laxman; Doiron, Curtis; Sears, John S; Brédas, Jean-Luc

    2012-11-01

    Polymers with low optical gaps are of importance to the organic photovoltaics community due to their potential for harnessing a large portion of the solar energy spectrum. The combination along their backbones of electron-rich and electron-deficient fragments contributes to the presence of low-lying excited states that are expected to display significant charge-transfer character. While conventional hybrid functionals are known to provide unsatisfactory results for charge-transfer excitations at the time-dependent DFT level, long-range corrected (LRC) functionals have been reported to give improved descriptions in a number of systems. Here, we use such LRC functionals, considering both tuned and default range-separation parameters, to characterize the absorption spectra of low-optical-gap systems of interest. Our results indicate that tuned LRC functionals lead to simulated optical-absorption properties in good agreement with experimental data. Importantly, the lowest-lying excited states (excitons) are shown to present a much more localized nature than initially anticipated.

  17. Hip-Hop Pop Art

    Science.gov (United States)

    Talley, Clarence, Sr.

    2011-01-01

    Art has a way of helping students better understand and appreciate the world around them, particularly the things that are most important to them. Hip hop is one of those generational genres that capture the attention of young students like few other things do. Drawing on this genre to get students to create art is an excellent way to demonstrate…

  18. Hip-Hop Pop Art

    Science.gov (United States)

    Talley, Clarence, Sr.

    2011-01-01

    Art has a way of helping students better understand and appreciate the world around them, particularly the things that are most important to them. Hip hop is one of those generational genres that capture the attention of young students like few other things do. Drawing on this genre to get students to create art is an excellent way to demonstrate…

  19. Processing Methods for Conical Scan Hopped-Frequency Signal

    Institute of Scientific and Technical Information of China (English)

    WANG Xiao-hong; LONG Teng

    2006-01-01

    The new radar system of combination of the hopped-frequency with the conical scanis presented. According to the principle and expression of the conical scan hopped-frequency signal, the angle processing method in which angle information is obtained by taking discrete Fourier transform (DFT) for the conical envelop o f each scattering centre by means of high range resolution profile (HRRP) is presented,and the corresponding formula is derived. The influence of non-ideal factors, such as amplitude fluctuation noise and system noise, leakage of time and frequency domain, unstable rotation of antenna, and missile rotation, on angle-measurement precision and the possible solving methods are also focused on. The simulation results show that the combination of the hopped-frequency and conical scan system could get satisfactory angle information, which could ensure good quality when used in practical tracking radar.

  20. Comparison of Rheological Properties of Hopped Wort and Malt Wort

    Directory of Open Access Journals (Sweden)

    Petr Trávníček

    2015-01-01

    Full Text Available The aim of this work is determination rheological properties of hopped wort and malt wort and their comparison. In the paper following rheological properties has been described: the dependence of viscosity on a temperature of a sample and hysteresis loop test. The time dependence test was performed for a confirmation thixotropic behaviour. Based on measured values Arrhenius mathematical model has been applied. The activation energy was determined by using of this model. Tests have been carried out in the temperature range from 5 °C to 40 °C. Rheological tests proved that malt wort behaves as Newtonian fluid in all temperatures and hopped wort behaves as non-Newtonian fluid at low temperatures. Thixotropic behaviour is caused by the content of the rests of hops heads or malt scraps.

  1. Hopping models and ac universality

    DEFF Research Database (Denmark)

    Dyre, Jeppe; Schrøder, Thomas

    2002-01-01

    Some general relations for hopping models are established. We proceed to discuss the universality of the ac conductivity which arises in the extreme disorder limit of the random barrier model. It is shown that the relevant dimension entering into the diffusion cluster approximation (DCA) is the h......) is the harmonic (fracton) dimension of the diffusion cluster. The temperature scaling of the dimensionless frequency entering into the DCA is discussed. Finally, some open problems regarding ac universality are listed.......Some general relations for hopping models are established. We proceed to discuss the universality of the ac conductivity which arises in the extreme disorder limit of the random barrier model. It is shown that the relevant dimension entering into the diffusion cluster approximation (DCA...

  2. Basin Hopping Graph

    DEFF Research Database (Denmark)

    Kucharik, Marcel; Hofacker, Ivo; Stadler, Peter

    2014-01-01

    basins when the direct transitions between them are “energetically favorable”. Edge weights endcode the corresponding saddle heights and thus measure the difficulties of these favorable transitions. BHGs can be approximated accurately and efficiently for RNA molecules well beyond the length range...... accessible to enumerative algorithms. Availability The algorithms described here are implemented in C++ as standalone programs. Its source code and supplemental material can be freely downloaded from http://www.tbi.univie.ac.at/bhg.html....

  3. Hopping Electron Transport in Doped Polyaniline: an Experimental Verification of the Fogler-Teber-Shklovskii Model

    OpenAIRE

    Baćani, Mirko; Novak, Mario; Kokanović, Ivan; Babić, Dinko

    2012-01-01

    We present a study of the temperature (T) dependence of the dc electrical conductivity of polyaniline pellets doped over a wide range. A crossover between low-T variable-range hopping and high-T nearest-neighbor hopping has been found below room temperature for most of the samples, which is atypical for conducting polymers. This allows us to construct an experimental diagram that accounts for different regimes in the hopping electron transport and closely resembles predictions of the Fogler-T...

  4. Hopping Electron Transport in Doped Polyaniline: an Experimental Verification of the Fogler-Teber-Shklovskii Model

    OpenAIRE

    Baćani, Mirko; Novak, Mario; Kokanović, Ivan; Babić, Dinko

    2012-01-01

    We present a study of the temperature (T) dependence of the dc electrical conductivity of polyaniline pellets doped over a wide range. A crossover between low-T variable-range hopping and high-T nearest-neighbor hopping has been found below room temperature for most of the samples, which is atypical for conducting polymers. This allows us to construct an experimental diagram that accounts for different regimes in the hopping electron transport and closely resembles predictions of the Fogler-T...

  5. The Power of Pictures : Vertical Picture Angles in Power Pictures

    NARCIS (Netherlands)

    Giessner, Steffen R.; Ryan, Michelle K.; Schubert, Thomas W.; van Quaquebeke, Niels

    2011-01-01

    Conventional wisdom suggests that variations in vertical picture angle cause the subject to appear more powerful when depicted from below and less powerful when depicted from above. However, do the media actually use such associations to represent individual differences in power? We argue that the d

  6. Hopping energy and percolation-type transport in p-GaAs low densities near the 2D metal-insulator transition at zero magnetic field

    Science.gov (United States)

    Dlimi, S.; El kaaouachi, A.; Narjis, A.; Limouny, L.; Sybous, A.; Errai, M.

    2013-10-01

    We investigated the temperature dependence of resistivity of a high mobility two-dimensional holes system grown on the (311) GaAs surface in the absence of the magnetic field near the metal-insulator transition. The Coulomb hopping was found in a wide range of temperature and carrier density. Quantitative analysis of our results suggests that a crossover from Efros-Shklovskii to Mott variable range hopping due to screening phenomenon when the hopping distance increases. We found that using the 2D single particle hopping amplitude CES gives unreasonably high localization lengths. Therefore, we believe that electrical transport is dominated by correlated hopping and the hopping amplitude must be renormalized by a reduction factor A≈1.6. The localization length appears to diverge in a power-law fashion near the transition point. The analysis of the hopping gives results consistent with the prediction of the critical point from a recent study of percolation and other experiences.

  7. Fundamentals of beer and hop chemistry

    OpenAIRE

    Denis de Keukeleire

    2000-01-01

    Beer brewing is an intricate process encompassing mixing and further elaboration of four essential raw materials, including barley malt, brewing water, hops and yeast. Particularly hops determine to a great extent typical beer qualities such as bitter taste, hoppy flavour, and foam stability. Conversely, hop-derived bitter acids account for an offending lightstruck flavour, which is formed on exposure of beer to light. These various processes are presented in detail, while due emphasis is pla...

  8. Fundamentals of beer and hop chemistry

    Directory of Open Access Journals (Sweden)

    Denis De Keukeleire

    2000-02-01

    Full Text Available Beer brewing is an intricate process encompassing mixing and further elaboration of four essential raw materials, including barley malt, brewing water, hops and yeast. Particularly hops determine to a great extent typical beer qualities such as bitter taste, hoppy flavour, and foam stability. Conversely, hop-derived bitter acids account for an offending lightstruck flavour, which is formed on exposure of beer to light. These various processes are presented in detail, while due emphasis is placed on state-of-the-art hop technology, which provides brewers with efficient means to control bitterness, foam, and light-stability thereby allowing for the production of beers with consistent quality.

  9. Routing for wireless multi-hop networks

    CERN Document Server

    Hamid, Sherin Abdel; Takahara, Glen

    2013-01-01

    The focus of this brief is to identify what unifies and what distinguishes the routing functions in four wireless multi-hop network paradigms. The brief introduces a generic routing model that can be used as a foundation of wireless multi-hop routing protocol analysis and design. It demonstrates that such model can be adopted by any wireless multi-hop routing protocol. Also presented is a glimpse of the ideal wireless multi-hop routing protocol along with several open issues.

  10. Relationships between Xanthohumol and Polyphenol Content in Hop Leaves and Hop Cones with Regard to Water Supply and Cultivar

    Directory of Open Access Journals (Sweden)

    Veronika Abram

    2007-09-01

    Full Text Available The effect of water supply – especially of drought stress – on the content ofsome secondary metabolites in hops (Humulus lupulus L. was studied. The experimenttook place in 2006. Some relevant data from 2005 were included for comparison. Leavesand cones of nine hop cultivars grown under field conditions as well as in a pot experimentunder three water regimes were analyzed. The cultivars ranged from those most grown inSlovenia to promising crossbreed being tested. Leaves were sampled from July 18, 2006 toAugust 18, 2006, while cones were picked in the time of technological maturity. Standardanalytical methods were applied to determine the contents of xanthohumol, polyphenolsand α-acids in hop leaves and hop cones. The contents of the secondary metabolites inquestion depended more on the cultivar under investigation than on the water supply, atleast as far the growing conditions for a relatively normal development of the plant weremet.

  11. Decoherence and mode-hopping in spin-torque oscillators

    Science.gov (United States)

    Muduli, Pranaba

    2013-03-01

    A Spin Torque Oscillator (STO) is a nano-sized magneto-resistive device that can produce microwave signals in the GHz range as a result of spin transfer torque- a phenomena which is receiving increasing importance in contemporary spintronics research both for fundamental spin physics as well as a number of possible microwave applications e.g., oscillator, detectors and modulators. A very important question, both for fundamental physics as well for applications, is what limits the coherence time of the STO. This is a subject of significant interest recently. Until now theoretical studies have investigated decoherence through thermal noise assuming that only a single mode is excited. On the other hand, experiments clearly show both the existence of multiple modes and persistent mode-hopping between several modes. The impact on coherence time of such mode-hopping has been largely unexplored and a theoretical study of its origin is entirely lacking. In this work, we will present first ever systematic experimental investigations of mode hopping, and its impact on the coherence time in a magnetic tunnel junction based spin torque oscillator. We will discuss micromagnetic simulations and a theoretical treatment to show that the non-conservative fields due to finite damping-either positive or negative (spin torque) -couple individual modes and, in the presence of thermal noise, govern the experimentally observed mode-hopping. Using quantitative analysis of both coherence and dwell times, we will show that mode-hopping could be a limiting factor for STO coherence. Finally we show how our theoretical treatment can be extended to the case of a metallic nanocontact based STO, where anomalous temperature dependence of linewidth is found as result of the mode coupling. and Department of Physics, Indian Institute of Technology Delhi, New Delhi-110016, India

  12. Hop-by-HopWorm Propagation with Carryover Epidemic Model in Mobile Sensor Networks

    Directory of Open Access Journals (Sweden)

    Jun-Won Ho

    2015-10-01

    Full Text Available In the internet, a worm is usually propagated in a random multi-hop contact manner. However, the attacker will not likely select this random multi-hop propagation approach in a mobile sensor network. This is because multi-hop worm route paths to random vulnerable targets can be often breached due to node mobility, leading to failure of fast worm spread under this strategy. Therefore, an appropriate propagation strategy is needed for mobile sensor worms. To meet this need, we discuss a hop-by-hop worm propagation model in mobile sensor networks. In a hop-by-hop worm propagation model, benign nodes are infected by worm in neighbor-to-neighbor spread manner. Since worm infection occurs in hop-by-hop contact, it is not substantially affected by a route breach incurred by node mobility. We also propose the carryover epidemic model to deal with the worm infection quota deficiency that might occur when employing an epidemic model in a mobile sensor network. We analyze worm infection capability under the carryover epidemic model. Moreover, we simulate hop-by-hop worm propagation with carryover epidemic model by using an ns-2 simulator. The simulation results demonstrate that infection quota carryovers are seldom observed where a node’s maximum speed is no less than 20 m/s.

  13. How Does a Hopping Kangaroo Breathe?

    Science.gov (United States)

    Giuliodori, Mauricio J.; Lujan, Heidi L.; Janbaih, Hussein; DiCarlo, Stephen E.

    2010-01-01

    We developed a model to demonstrate how a hopping kangaroo breathes. Interestingly, a kangaroo uses less energy to breathe while hopping than while standing still. This occurs, in part, because rather than using muscle power to move air into and out of the lungs, air is pulled into (inspiration) and pushed out of (expiration) the lungs as the…

  14. Hip-hop and urban studies

    NARCIS (Netherlands)

    Jaffe, R.

    2014-01-01

    How can urban studies research engage fruitfully with hip-hop? This contribution responds to the essays by David Beer and Martin Lamotte on ‘street music’, urban ethnography and ghettoized communities. It discusses how a social science engagement with hip-hop texts might differ from cultural studies

  15. Pertunjukan Teater Karo Hip Hop Kontemporer KAI

    Directory of Open Access Journals (Sweden)

    Silvia Anggreni Purba

    2013-11-01

    Full Text Available Pertunjukan ini berawal dari sebuah ide untuk mengkolaborasikan tradisi Karo dengan budaya populer. Dengan cara seperti ini pertunjukan bisa dinikmati tanpa batasan bahasa dan budaya. Proses menggabungkan dua budaya yang berbeda merupakan bentuk budaya hibrida dan terjadi akibat proses globalisasi. Melalui proses pengendapan pengamatan dan kesan yang kuat, pertunjukan ini dibawa ke dalam bentuk Hip Hop. Pertunjukan ini merupakan bagian dari sebuah tragedi modern dengan karakter destruktif, mengeksplorasi emosi dan menyampaikannya kepada penonton. Eksplorasi budaya Karo dan tari Hip Hop sebagai bahasa simbol mampu memperkuat kata-kata. Gerak tidak diungkapkan dengan kata lisan tetapi disajikan melalui gerak tari Hip Hop. Penafsiran legenda dan teks ke dalam gerak, melalui proses pelatihan di laboratorium sebagai proses pencarian dan eksperimentasi diwujudkan dengan mempertimbangkan unsur-unsur dasar dari Hip Hop, unsur budaya Karo dan tontonan. Karo Hip Hop diharapkan menjadi bentuk estetika teater modern yang diinginkan tanpa kehilangan tradisi.Kata kunci: Tari Karo kontemporer, Hip-hop, budaya hibridaABSTRACTPertunjukan Teater Karo Hip Hop Kontemporer KAI. The performance of Karo Theater collaborated with Hip Hop stems from a simple idea to collaborate Karo cultural traditions with popular culture. The performances can be enjoyed without having limitation on the language and culture. The process of combining two different cultures is a form of hybrid culture, and it may occur due to the globalization process. Through the process of deposition of the observations and strong impression, this performance is then brought into the form of Hip Hop as a preferred form which is energetic, personal and global. This performance is part of a modern tragedy with its destructive character which has explored the emotion and has presented it to the audiences. The exploration of Karo cultural tradition and Hip Hop dance as a language of symbols is able to

  16. Effect of doping Ca on polaron hopping in LaSr2Mn2O7

    Indian Academy of Sciences (India)

    S N Bhatia; Osama A Yassin

    2002-05-01

    From the transport studies in the bilayer manganites LaSr2-CaMn2O7, we have found the variable-range hopping model proposed by Viret et al to be inadequate to describe the transport of charge in these materials. The polarons appear to hop to their nearest neighbors with an activation energy, which in part is dependent on the magnetic interactions in the lattice.

  17. Multidimensional radar picture

    Science.gov (United States)

    Waz, Mariusz

    2010-05-01

    In marine navigation systems, the three-dimensional (3D) visualization is often and often used. Echosonders and sonars working in hydroacustic systems can present pictures in three dimensions. Currently, vector maps also offer 3D presentation. This presentation is used in aviation and underwater navigation. In the nearest future three-dimensional presentation may be obligatory presentation in displays of navigation systems. A part of these systems work with radar and communicates with it transmitting data in a digital form. 3D presentation of radar picture require a new technology to develop. In the first step it is necessary to compile digital form of radar signal. The modern navigation radar do not present data in three-dimensional form. Progress in technology of digital signal processing make it possible to create multidimensional radar pictures. For instance, the RSC (Radar Scan Converter) - digital radar picture recording and transforming tool can be used to create new picture online. Using RSC and techniques of modern computer graphics multidimensional radar pictures can be generated. The radar pictures mentioned should be readable for ECDIS. The paper presents a method for generating multidimensional radar picture from original signal coming from radar receiver.

  18. Space perception in pictures

    NARCIS (Netherlands)

    Van Doorn, A.J.; Wagemans, J.; De Ridder, H.; Koenderink, J.J.

    2011-01-01

    A "picture" is a at object covered with pigments in a certain pattern. Human observers, when looking "into" a picture (photograph, painting, drawing, . . . say) often report to experience a three dimensional "pictorial space." This space is a mental entity, apparently triggered by so called pictori

  19. Nerve Conduction Through Dendrites via Proton Hopping.

    Science.gov (United States)

    Kier, Lemont B

    2017-01-01

    In our previous studies of nerve conduction conducted by proton hopping, we have considered the axon, soma, synapse and the nodes of Ranvier. The role of proton hopping described the passage of information through each of these units of a typical nerve system. The synapse projects information from the axon to the dendrite and their associated spines. We have invoked the passage of protons via a hopping mechanism to illustrate the continuum of the impulse through the system, via the soma following the dendrites. This is proposed to be a continuum invoked by the proton hopping method. With the proposal of the activity through the dendrites, via proton hopping, a complete model of the nerve function is invoked. At each step to the way, a water pathway is present and is invoked in the proposed model as the carrier of the message via proton hopping. The importance of the dendrites is evident by the presence of a vast number of spines, each possessing the possibility to carry unique messages through the nervous system. With this model of the role of dendrites, functioning with the presence of proton hopping, a complete model of the nerve system is presented. The validity of this model will be available for further studies and models to assess it's validity. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  20. Dielectric relaxation and hopping conduction in reduced graphite oxide

    Science.gov (United States)

    Wei, Guidan; Yu, Ji; Gu, Min; Tang, Tong B.

    2016-06-01

    Graphite oxide reduced by sodium borohydride was characterised and its electrical conduction investigated with impedance spectroscopy. Thermal dependence of electrical modulus (instead of permittivity, its inverse) was calculated from complex impedance spectra, an approach that prevents any peak in dielectric loss (imaginary component) from being swarmed by large dc conductivity. Two loss peaks appeared at each tested frequency, in a sample of either degree of reduction. The set of weaker peak should arise from the relaxation of some polar bonds, as proposed earlier by us. The stronger loss peaks may correspond to the hopping of conduction electrons; variable range hopping is also consistent with the observed thermal dependence of conductivity. However, nearer ambient temperature there is a change in mechanism, to band transport, with an activation energy of fairly similar values as derived from both loss peaks and conductivity.

  1. Picturing the Heart

    Science.gov (United States)

    ... Links for Students Glossary Picturing the Heart SCIENCE EDUCATION Science Topics Resource Links for General Public Resource Links for Parents/Teachers Resource Links for Students Glossary Government Resources Kids.gov – Science Information and services on the web ...

  2. Vision and Motion Pictures.

    Science.gov (United States)

    Grambo, Gregory

    1998-01-01

    Presents activities on persistence of vision that involve students in a hands-on approach to the study of early methods of creating motion pictures. Students construct flip books, a Zoetrope, and an early movie machine. (DDR)

  3. Accurate water maser positions from HOPS

    CERN Document Server

    Walsh, Andrew J; Longmore, Steven N; Breen, Shari L; Green, James A; Harvey-Smith, Lisa; Jordan, Christopher H; Macpherson, Christopher

    2014-01-01

    We report on high spatial resolution water maser observations, using the Australia Telescope Compact Array, towards water maser sites previously identified in the H2O southern Galactic Plane Survey (HOPS). Of the 540 masers identified in the single-dish observations of Walsh et al. (2011), we detect emission in all but 31 fields. We report on 2790 spectral features (maser spots), with brightnesses ranging from 0.06 Jy to 576Jy and with velocities ranging from -238.5 to +300.5km/s. These spectral features are grouped into 631 maser sites. We have compared the positions of these sites to the literature to associate the sites with astrophysical objects. We identify 433 (69 per cent) with star formation, 121 (19 per cent) with evolved stars and 77 (12 per cent) as unknown. We find that maser sites associated with evolved stars tend to have more maser spots and have smaller angular sizes than those associated with star formation. We present evidence that maser sites associated with evolved stars show an increased ...

  4. Yangliuqing New Year Pictures

    Institute of Scientific and Technical Information of China (English)

    1993-01-01

    HANGING up New Yearpictures during khe SpringFestival to symbolize goodluck in the coming year has longbeen a tradition in China,The pic-tures are both colorful and jubilantin theme and composition so as toattract everything good in the com-ing year and drive away evil.Four main“schools” of folk artdealing with New Year pictures ex-ist.Among the best known is thewoodblocK print from Yangliuqing,

  5. The universal zulu nation in colombia, social impact of hip hop culture in the Valley of Aburrá

    Directory of Open Access Journals (Sweden)

    Camilo Arias

    2016-04-01

    Full Text Available The effervescence of organizational movements around the cultural practices of Hip Hop in the Valley of Aburrá, alternatives are thought of together and to propose structural changes to their environments, from social interventions with communities’ ways. That is why we consider it necessary to make a tour of the historical and social factors that have shaped what we now know as Hip Hop Culture, to generate with this a picture of their impact on the cultural scene at local and national level.

  6. Helicobacter pylori HopE and HopV porins present scarce expression among clinical isolates

    Institute of Scientific and Technical Information of China (English)

    Maritza; Lienlaf; Juan; Pablo; Morales; María; Inés; Díaz; Rodrigo; Díaz; Elsa; Bruce; Freddy; Siegel; Gloria; León; Paul; R; Harris; Alejandro; Venegas

    2010-01-01

    AIM:To evaluate how widely Helicobacter pylori (H. pylori ) HopE and HopV porins are expressed among Chilean isolates and how seroprevalent they are among infected patients in Chile.METHODS: H. pylori hopE and hopV genes derived from strain CHCTX-1 were cloned by polymerase chain reaction (PCR), sequenced and expressed in Escherichia coli AD494 (DE3). Gel-purified porins were used to prepare polyclonal antibodies. The presence of both genes was tested by PCR in a collection of H. pylori clinical isolates an...

  7. Hip-hop, Onegin - pop! / Tatjana Aleksandrova

    Index Scriptorium Estoniae

    Aleksandrova, Tatjana, 1945-

    2004-01-01

    Erateatrikooli KS, mida juhib Svetlana Krassman, lavastus A. Pushkini poeemi "Jevgeni Onegin" motiividel. Noortelavastuse muusikalises seades kasutatakse klassikalise muusika aranzheeringuid ja räppi, kostüümidraamat koos hip-hop rõivastiiliga

  8. Hip-hop, Onegin - pop! / Tatjana Aleksandrova

    Index Scriptorium Estoniae

    Aleksandrova, Tatjana, 1945-

    2004-01-01

    Erateatrikooli KS, mida juhib Svetlana Krassman, lavastus A. Pushkini poeemi "Jevgeni Onegin" motiividel. Noortelavastuse muusikalises seades kasutatakse klassikalise muusika aranzheeringuid ja räppi, kostüümidraamat koos hip-hop rõivastiiliga

  9. Involvement of Vacuolar Sequestration and Active Transport in Tolerance of Saccharomyces cerevisiae to Hop Iso-α-Acids▿ † ¶

    Science.gov (United States)

    Hazelwood, Lucie A.; Walsh, Michael C.; Pronk, Jack T.; Daran, Jean-Marc

    2010-01-01

    The hop plant, Humulus lupulus L., has an exceptionally high content of secondary metabolites, the hop α-acids, which possess a range of beneficial properties, including antiseptic action. Studies performed on the mode of action of hop iso-α-acids have hitherto been restricted to lactic acid bacteria. The present study investigated molecular mechanisms of hop iso-α-acid resistance in the model eukaryote Saccharomyces cerevisiae. Growth inhibition occurred at concentrations of hop iso-α-acids that were an order of magnitude higher than those found with hop-tolerant prokaryotes. Chemostat-based transcriptome analysis and phenotype screening of the S. cerevisiae haploid gene deletion collection were used as complementary methods to screen for genes involved in hop iso-α-acid detoxification and tolerance. This screening and further analysis of deletion mutants confirmed that yeast tolerance to hop iso-α-acids involves three major processes, active proton pumping into the vacuole by the vacuolar-type ATPase to enable vacuolar sequestration of iso-α-acids and alteration of cell wall structure and, to a lesser extent, active export of iso-α-acids across the plasma membrane. Furthermore, iso-α-acids were shown to affect cellular metal homeostasis by acting as strong zinc and iron chelators. PMID:19915041

  10. Involvement of vacuolar sequestration and active transport in tolerance of Saccharomyces cerevisiae to hop iso-alpha-acids.

    Science.gov (United States)

    Hazelwood, Lucie A; Walsh, Michael C; Pronk, Jack T; Daran, Jean-Marc

    2010-01-01

    The hop plant, Humulus lupulus L., has an exceptionally high content of secondary metabolites, the hop alpha-acids, which possess a range of beneficial properties, including antiseptic action. Studies performed on the mode of action of hop iso-alpha-acids have hitherto been restricted to lactic acid bacteria. The present study investigated molecular mechanisms of hop iso-alpha-acid resistance in the model eukaryote Saccharomyces cerevisiae. Growth inhibition occurred at concentrations of hop iso-alpha-acids that were an order of magnitude higher than those found with hop-tolerant prokaryotes. Chemostat-based transcriptome analysis and phenotype screening of the S. cerevisiae haploid gene deletion collection were used as complementary methods to screen for genes involved in hop iso-alpha-acid detoxification and tolerance. This screening and further analysis of deletion mutants confirmed that yeast tolerance to hop iso-alpha-acids involves three major processes, active proton pumping into the vacuole by the vacuolar-type ATPase to enable vacuolar sequestration of iso-alpha-acids and alteration of cell wall structure and, to a lesser extent, active export of iso-alpha-acids across the plasma membrane. Furthermore, iso-alpha-acids were shown to affect cellular metal homeostasis by acting as strong zinc and iron chelators.

  11. Beer spoilage bacteria and hop resistance.

    Science.gov (United States)

    Sakamoto, Kanta; Konings, Wil N

    2003-12-31

    For brewing industry, beer spoilage bacteria have been problematic for centuries. They include some lactic acid bacteria such as Lactobacillus brevis, Lactobacillus lindneri and Pediococcus damnosus, and some Gram-negative bacteria such as Pectinatus cerevisiiphilus, Pectinatus frisingensis and Megasphaera cerevisiae. They can spoil beer by turbidity, acidity and the production of unfavorable smell such as diacetyl or hydrogen sulfide. For the microbiological control, many advanced biotechnological techniques such as immunoassay and polymerase chain reaction (PCR) have been applied in place of the conventional and time-consuming method of incubation on culture media. Subsequently, a method is needed to determine whether the detected bacterium is capable of growing in beer or not. In lactic acid bacteria, hop resistance is crucial for their ability to grow in beer. Hop compounds, mainly iso-alpha-acids in beer, have antibacterial activity against Gram-positive bacteria. They act as ionophores which dissipate the pH gradient across the cytoplasmic membrane and reduce the proton motive force (pmf). Consequently, the pmf-dependent nutrient uptake is hampered, resulting in cell death. The hop-resistance mechanisms in lactic acid bacteria have been investigated. HorA was found to excrete hop compounds in an ATP-dependent manner from the cell membrane to outer medium. Additionally, increased proton pumping by the membrane bound H(+)-ATPase contributes to hop resistance. To energize such ATP-dependent transporters hop-resistant cells contain larger ATP pools than hop-sensitive cells. Furthermore, a pmf-dependent hop transporter was recently presented. Understanding the hop-resistance mechanisms has enabled the development of rapid methods to discriminate beer spoilage strains from nonspoilers. The horA-PCR method has been applied for bacterial control in breweries. Also, a discrimination method was developed based on ATP pool measurement in lactobacillus cells. However

  12. Fast Hopping Frequency Generation in Digital CMOS

    CERN Document Server

    Farazian, Mohammad; Gudem, Prasad S

    2013-01-01

    Overcoming the agility limitations of conventional frequency synthesizers in multi-band OFDM ultra wideband is a key research goal in digital technology. This volume outlines a frequency plan that can generate all the required frequencies from a single fixed frequency, able to implement center frequencies with no more than two levels of SSB mixing. It recognizes the need for future synthesizers to bypass on-chip inductors and operate at low voltages to enable the increased integration and efficiency of networked appliances. The author examines in depth the architecture of the dividers that generate the necessary frequencies from a single base frequency and are capable of establishing a fractional division ratio.   Presenting the first CMOS inductorless single PLL 14-band frequency synthesizer for MB-OFDMUWB makes this volume a key addition to the literature, and with the synthesizer capable of arbitrary band-hopping in less than two nanoseconds, it operates well within the desired range on a 1.2-volt power s...

  13. Improving the sensitivity of the hop index in patients with an ACL deficient knee by transforming the hop distance scores

    Directory of Open Access Journals (Sweden)

    Thomas Scott G

    2006-02-01

    Full Text Available Abstract Background The one leg hop for distance is one of the most commonly employed functional tests utilized in the evaluation of the ACL deficient and reconstructed patient. While the reliability of the hop test scores has been well established, validity studies have revealed low sensitivity rates in detecting functional limitations using the hop index (the ratio or percentage of limb performance. However, the impact of the inherent limitations associated with the hop index have not been investigated to date. One specific limitation relates to the impact of the differences in the underlying hop distance scores. Therefore, this pilot study set out to determine: 1 the impact that between limb differences in hop distance has on the sensitivity of the hop index in detecting functional limitations and; 2 whether a logarithmic transformation of the underlying hop distance scores improves the sensitivity of the hop index. Methods A cross sectional design involving the evaluation of one leg hop for distance performance in a consecutive sample of 10 ACL deficient males with an isolated ACL tear awaiting reconstructive surgery and nine gender, age-matched controls. Results In the ACL deficient, the hop index was associated with the distance hopped on the non-injured limb (r = -0.66, p = 0.04 but not on the injured limb. Transformation (logarithmic of the hop distance scores and re-calculation of the hop index using the transformed scores increased the sensitivity of the hop index in the detection of functional limitations from 20 to 60% and 50 to 70% using the normal limb symmetry reference norms of ≥ 85% and 90% respectively. Conclusion The distance hopped on the non-injured limb is a critical factor in detecting functional limitations using the hop index in patients with an ACL deficient knee. Logarithmic transformation of the hop distance scores minimizes the effect of the arithmetic differences between limbs however; the sensitivity of the hop

  14. Dynamic molecular graphs: "hopping" structures.

    Science.gov (United States)

    Cortés-Guzmán, Fernando; Rocha-Rinza, Tomas; Guevara-Vela, José Manuel; Cuevas, Gabriel; Gómez, Rosa María

    2014-05-05

    This work aims to contribute to the discussion about the suitability of bond paths and bond-critical points as indicators of chemical bonding defined within the theoretical framework of the quantum theory of atoms in molecules. For this purpose, we consider the temporal evolution of the molecular structure of [Fe{C(CH2 )3 }(CO)3 ] throughout Born-Oppenheimer molecular dynamics (BOMD), which illustrates the changing behaviour of the molecular graph (MG) of an electronic system. Several MGs with significant lifespans are observed across the BOMD simulations. The bond paths between the trimethylenemethane and the metallic core are uninterruptedly formed and broken. This situation is reminiscent of a "hopping" ligand over the iron atom. The molecular graph wherein the bonding between trimethylenemethane and the iron atom takes place only by means of the tertiary carbon atom has the longest lifespan of all the considered structures, which is consistent with the MG found by X-ray diffraction experiments and quantum chemical calculations. In contrast, the η(4) complex predicted by molecular-orbital theory has an extremely brief lifetime. The lifespan of different molecular structures is related to bond descriptors on the basis of the topology of the electron density such as the ellipticities at the FeCH2 bond-critical points and electron delocalisation indices. This work also proposes the concept of a dynamic molecular graph composed of the different structures found throughout the BOMD trajectories in analogy to a resonance hybrid of Lewis structures. It is our hope that the notion of dynamic molecular graphs will prove useful in the discussion of electronic systems, in particular for those in which analysis on the basis of static structures leads to controversial conclusions. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Voyager picture of Jupiter

    Science.gov (United States)

    1998-01-01

    NASA's Voyager 1 took this picture of the planet Jupiter on Saturday, Jan. 6, the first in its three-month-long, close-up investigation of the largest planet. The spacecraft, flying toward a March 5 closest approach, was 35.8 million miles (57.6 million kilometers) from Jupiter and 371.7 million miles (598.2 million kilometers) from Earth when the picture was taken. As the Voyager cameras begin their meteorological surveillance of Jupiter, they reveal a dynamic atmosphere with more convective structure than had previously been thought. While the smallest atmospheric features seen in this picture are still as large as 600 miles (1,000 kilometers) across, Voyager will be able to detect individual storm systems as small as 3 miles (5 kilometers) at closest approach. The Great Red Spot can be seen near the limb at the far right. Most of the other features are too small to be seen in terrestrial telescopes. This picture was transmitted to the Jet Propulsion Laboratory through the Deep Space Network's tracking station at Madrid, Spain. The Voyager Project is managed for NASA by Caltech's Jet Propulsion Laboratory.

  16. Knowledge From Pictures (KFP)

    Science.gov (United States)

    Truszkowski, Walt; Paterra, Frank; Bailin, Sidney

    1993-01-01

    The old maxim goes: 'A picture is worth a thousand words'. The objective of the research reported in this paper is to demonstrate this idea as it relates to the knowledge acquisition process and the automated development of an expert system's rule base. A prototype tool, the Knowledge From Pictures (KFP) tool, has been developed which configures an expert system's rule base by an automated analysis of and reasoning about a 'picture', i.e., a graphical representation of some target system to be supported by the diagnostic capabilities of the expert system under development. This rule base, when refined, could then be used by the expert system for target system monitoring and fault analysis in an operational setting. Most people, when faced with the problem of understanding the behavior of a complicated system, resort to the use of some picture or graphical representation of the system as an aid in thinking about it. This depiction provides a means of helping the individual to visualize the bahavior and dynamics of the system under study. An analysis of the picture augmented with the individual's background information, allows the problem solver to codify knowledge about the system. This knowledge can, in turn, be used to develop computer programs to automatically monitor the system's performance. The approach taken is this research was to mimic this knowledge acquisition paradigm. A prototype tool was developed which provides the user: (1) a mechanism for graphically representing sample system-configurations appropriate for the domain, and (2) a linguistic device for annotating the graphical representation with the behaviors and mutual influences of the components depicted in the graphic. The KFP tool, reasoning from the graphical depiction along with user-supplied annotations of component behaviors and inter-component influences, generates a rule base that could be used in automating the fault detection, isolation, and repair of the system.

  17. Hopping conduction in In-doped CuO thin films

    Science.gov (United States)

    Yildiz, A.; Horzum, Ş.; Serin, N.; Serin, T.

    2014-11-01

    Electrical transport properties of undoped and In-doped CuO thin films (1, 5 and 10 at. %) are investigated by mean of resistivity in the temperature range of 115-300 K. Electrical transport mechanism of films is explained on the basis of the variable-range hopping (VRH) conduction. Upon doping, appreciable changes are found in resistivity. Temperature dependent resistivity shows a complex correlation with increasing In concentration. This situation is well explained by fluctuations in the hopping distance and the density of states at the Fermi level.

  18. Tailoring the photon hopping by nearest and next-nearest-neighbour interaction in photonic arrays

    CERN Document Server

    Caselli, Niccolò; La China, Federico; Gerardino, Annamaria; Li, Lianhe; Linfield, Edmund H; Pagliano, Francesco; Fiore, Andrea; Intonti, Francesca; Gurioli, Massimo

    2015-01-01

    Arrays of photonic cavities are relevant structures for developing large-scale photonic integrated circuits and for investigating basic quantum electrodynamics phenomena, due to the photon hopping between interacting nanoresonators. Here, we investigate, by means of scanning near-field spectroscopy, numerical calculations and an analytical model, the role of different neighboring interactions that give rise to delocalized supermodes in different photonic crystal array configurations. The systems under investigation consist of three nominally identical two-dimensional photonic crystal nanocavities on membrane aligned along the two symmetry axes of the triangular photonic crystal lattice. We find that the nearest and next-nearest-neighbour coupling terms can be of the same relevance. In this case, a non-intuitive picture describes the resonant modes, and the photon hopping between adjacent nano-resonators is strongly affected. Our findings prove that exotic configurations and even post-fabrication engineering o...

  19. Enhancement of hopping conductivity by spontaneous fractal ordering of low-energy sites

    Science.gov (United States)

    Chen, Tianran; Skinner, Brian

    2016-08-01

    Variable-range hopping conductivity has long been understood in terms of a canonical prescription for relating the single-particle density of states to the temperature-dependent conductivity. Here we demonstrate that this prescription breaks down in situations where a large and long-ranged random potential develops. In particular, we examine a canonical model of a completely compensated semiconductor, and we show that at low temperatures hopping proceeds along self-organized, low-dimensional subspaces having fractal dimension d =2 . We derive and study numerically the spatial structure of these subspaces, as well as the conductivity and density of states that result from them. One of our prominent findings is that fractal ordering of low energy sites greatly enhances the hopping conductivity and allows Efros-Shklovskii type conductivity to persist up to unexpectedly high temperatures.

  20. Hidden String Order in a Hole Superconductor with Extended Correlated Hopping.

    Science.gov (United States)

    Chhajlany, Ravindra W; Grzybowski, Przemysław R; Stasińska, Julia; Lewenstein, Maciej; Dutta, Omjyoti

    2016-06-01

    Ultracold fermions in one-dimensional, spin-dependent nonoverlapping optical lattices are described by a nonstandard Hubbard model with next-nearest-neighbor correlated hopping. In the limit of a kinetically constraining value of the correlated hopping equal to the normal hopping, we map the invariant subspaces of the Hamiltonian exactly to free spinless fermion chains of varying lengths. As a result, the system exactly manifests spin-charge separation and we obtain the system properties for arbitrary filling: ground state collective order characterized by a spin gap, which can be ascribed to an unconventional critical hole superconductor associated with finite long range nonlocal string order. We study the system numerically away from the integrable point and show the persistence of both long range string order and spin gap for appropriate parameters as well as a transition to a ferromagnetic state.

  1. Landau-Zener type surface hopping algorithms

    CERN Document Server

    Belyaev, Andrey K; Trigila, Giulio

    2014-01-01

    A class of surface hopping algorithms is studied comparing two recent Landau-Zener (LZ) formulas for the probability of nonadiabatic transitions. One of the formulas requires a diabatic representation of the potential matrix while the other one depends only on the adiabatic potential energy surfaces. For each classical trajectory, the nonadiabatic transitions take place only when the surface gap attains a local minimum. Numerical experiments are performed with deterministically branching trajectories and with probabilistic surface hopping. The deterministic and the probabilistic approach confirm the good agreement of both the LZ probabilities as well the good approximation of the reference solution computed solving the Schroedinger equation via a grid based pseudo-spectral method. Visualizations of position expectations and superimposed surface hopping trajectories with reference position densities illustrate the effective dynamics of the investigated algorithms.

  2. Conscious Hip-Hop, Change, and the Obama Era

    Directory of Open Access Journals (Sweden)

    Murray Forman

    2010-05-01

    Full Text Available This article identifies a particular aspect of hip-hop’s range of cultural production—conscious rap—in order to isolate one of the more politicized discursive options available to youth in America and a site where critical perspectives on post-Civil Rights America have emerged most forcefully. It further suggests that Obama’s political rise corresponds with a new phase in hip-hop and has impacted the ways in which its creative artists frame and articulate issues of race, class, and identity.

  3. Anderson localization in one-dimensional quasiperiodic lattice models with nearest- and next-nearest-neighbor hopping

    Energy Technology Data Exchange (ETDEWEB)

    Gong, Longyan, E-mail: lygong@njupt.edu.cn [Information Physics Research Center and Department of Applied Physics, Nanjing University of Posts and Telecommunications, Nanjing, 210003 (China); Institute of Signal Processing and Transmission, Nanjing University of Posts and Telecommunications, Nanjing, 210003 (China); National Laboratory of Solid State Microstructures, Nanjing University, Nanjing 210093 (China); Feng, Yan; Ding, Yougen [Information Physics Research Center and Department of Applied Physics, Nanjing University of Posts and Telecommunications, Nanjing, 210003 (China); Institute of Signal Processing and Transmission, Nanjing University of Posts and Telecommunications, Nanjing, 210003 (China)

    2017-02-12

    Highlights: • Quasiperiodic lattice models with next-nearest-neighbor hopping are studied. • Shannon information entropies are used to reflect state localization properties. • Phase diagrams are obtained for the inverse bronze and golden means, respectively. • Our studies present a more complete picture than existing works. - Abstract: We explore the reduced relative Shannon information entropies SR for a quasiperiodic lattice model with nearest- and next-nearest-neighbor hopping, where an irrational number is in the mathematical expression of incommensurate on-site potentials. Based on SR, we respectively unveil the phase diagrams for two irrationalities, i.e., the inverse bronze mean and the inverse golden mean. The corresponding phase diagrams include regions of purely localized phase, purely delocalized phase, pure critical phase, and regions with mobility edges. The boundaries of different regions depend on the values of irrational number. These studies present a more complete picture than existing works.

  4. Teaching Grammar Using Pictures

    Directory of Open Access Journals (Sweden)

    Henny Uswatun Hasanah

    2015-05-01

    Full Text Available Teaching is a process of communication. It has to be created through the way ofteaching and exchanging the message or information by every teacher and student. The message can be knowledge, skills, ideas, experiences, and manyothers. Through the process of communication, the people can receive the message or information. To avoid misunderstanding in the process ofcommunication, media are needed in the process of teaching. Using pictures can make exercises and activities more interesting and more interactive. We canconstantly improve our activities by looking at what went well and what fell flat. These 5 unique ways to practice grammar using pictures are a jumping offpoint, and can be expanded in lots of interesting ways. 

  5. My Favorite Picture

    Institute of Scientific and Technical Information of China (English)

    赵阳

    2007-01-01

    <正>I have many pictures.But one of them is my favortie.Now,I introduce it to everyone.The picture has three people.They are mother,father and I.Look! This is me.I am in middle of them.I have long,black hair.I have black eyes and red mouth.I like drawing pictures.My favorite food is noodle,and I don’t like to eat dumplings.Look! On the right is my father,my father is tall and he has black hair and black eyes.He likes to play ping-pong.My mother is on the left.She has black,curly hair.Her mouth is big.We have the same big mouths.She likes to go for a walk in the park.I am very pretty.My father is handsome and my mother is beautiful.I love my family very much.

  6. Getting a Picture.

    Science.gov (United States)

    Nagel, Daniel A; Stacey, Dawn; Momtahan, Kathryn; Gifford, Wendy; Doucet, Shelley; Etowa, Josephine B

    2017-03-01

    Delivery of care by nurses in virtual environments is rapidly increasing with uptake of digitally mediated technologies, such as remote patient monitoring (RPM). Knowing the person is a phenomenon in nursing practice deemed requisite to building relationships and informing clinical decisions, but it has not been studied in virtual environments. The intent of this study was to explicate the processes of how nurses come to know the person using RPM, one form of telehealth technology used in a virtual environment. The study was informed by Charmaz's constructivist grounded theory and included 33 interviews and 5 observational experiences of nurses using RPM in 7 different settings. Getting a Picture evolved as the core category to a theoretical conceptualization of nurses knowing the person through use of RPM and other technologies, such as telephone and electronic medical records. Getting a Picture reflected a dynamic flow and integration of seven processes, such as Connecting With the Person and Recording and Reflecting, to describe how nurses strove to attain a visualization of the person. While navigating disparate and disconnected information and communication technologies, Getting a Picture was important for providing safe, holistic, person-centered care.

  7. Design, testing, and performance of a hybrid micro vehicle---The Hopping Rotochute

    Science.gov (United States)

    Beyer, Eric W.

    is shown to validate the dynamic model. Using the validated dynamic model, simulations were performed to better understand the dynamics of the device. In addition, key parameters such as system weight, rotor speed, internal mass weight and location, as well as battery capacity are varied to explore and optimize flight performance characteristics such as single hop height and range, number of hops, and total achievable range. The sensitivity of the Hopping Rotochute to atmospheric winds is also investigated as is the ability of the device to perform trajectory shaping.

  8. HPLC Analysis of [Alpha]- and [Beta]-Acids in Hops

    Science.gov (United States)

    Danenhower, Travis M.; Force, Leyna J.; Petersen, Kenneth J.; Betts, Thomas A.; Baker, Gary A.

    2008-01-01

    Hops have been used for centuries to impart aroma and bitterness to beer. The cones of the female hop plant contain both essential oils, which include many of the fragrant components of hops, and a collection of compounds known as [alpha]- and [beta]-acids that are the precursors to bittering agents. In order for brewers to predict the ultimate…

  9. Revolutionizing Environmental Education through Indigenous Hip Hop Culture

    Science.gov (United States)

    Gorlewski, Julie; Porfilio, Brad J.

    2012-01-01

    Based upon the life histories of six Indigenous hip hop artists of the Beat Nation artist collective, this essay captures how Indigenous hip hop has the potential to revolutionize environmental education. Hip hop provides Indigenous youth an emancipatory space to raise their opposition to neocolonial controls of Indigenous territories that…

  10. Revolutionizing Environmental Education through Indigenous Hip Hop Culture

    Science.gov (United States)

    Gorlewski, Julie; Porfilio, Brad J.

    2012-01-01

    Based upon the life histories of six Indigenous hip hop artists of the Beat Nation artist collective, this essay captures how Indigenous hip hop has the potential to revolutionize environmental education. Hip hop provides Indigenous youth an emancipatory space to raise their opposition to neocolonial controls of Indigenous territories that…

  11. HPLC Analysis of [Alpha]- and [Beta]-Acids in Hops

    Science.gov (United States)

    Danenhower, Travis M.; Force, Leyna J.; Petersen, Kenneth J.; Betts, Thomas A.; Baker, Gary A.

    2008-01-01

    Hops have been used for centuries to impart aroma and bitterness to beer. The cones of the female hop plant contain both essential oils, which include many of the fragrant components of hops, and a collection of compounds known as [alpha]- and [beta]-acids that are the precursors to bittering agents. In order for brewers to predict the ultimate…

  12. Uudised : Ooper. Hip-hop. Madonna

    Index Scriptorium Estoniae

    2005-01-01

    Rumeenia sopran Nelly Miricioiu Vincenzo Bellini ooperi "Norma" nimiosas Nederlandse Operas Amsaterdamis 7.-28. märtsini. 4. märtsil Tallinna klubis Hollywood üritusel "Hip-Hop Café" New Yorgi duo Camp Lo. Ameerika poplaulja Madonna võttis vastu filmirolli

  13. The Philippine "Hip Hop Stick Dance"

    Science.gov (United States)

    Lewis, Lisa

    2012-01-01

    This article introduces a dance that blends the traditional cultural heritage of the Philippines with modern music and moves. "Hip Hop Stick Dance" incorporates Tinikling (the Philippine national dance) and Arnis (a Filipino style of martial arts) to create a contemporary combination of rhythm, dance, and fitness. It was designed to introduce…

  14. Forecasting and management of hop downy mildew

    Science.gov (United States)

    Downy mildew of hop, caused by Pseudoperonospora humuli, is managed in the Pacific Northwestern U.S. by regular application of fungicides. A degree-day model that forecasts the first emergence of shoots systemically infection with P. humuli (termed basal spikes) and a risk index for secondary sprea...

  15. Uudised : Ooper. Hip-hop. Madonna

    Index Scriptorium Estoniae

    2005-01-01

    Rumeenia sopran Nelly Miricioiu Vincenzo Bellini ooperi "Norma" nimiosas Nederlandse Operas Amsaterdamis 7.-28. märtsini. 4. märtsil Tallinna klubis Hollywood üritusel "Hip-Hop Café" New Yorgi duo Camp Lo. Ameerika poplaulja Madonna võttis vastu filmirolli

  16. The Philippine "Hip Hop Stick Dance"

    Science.gov (United States)

    Lewis, Lisa

    2012-01-01

    This article introduces a dance that blends the traditional cultural heritage of the Philippines with modern music and moves. "Hip Hop Stick Dance" incorporates Tinikling (the Philippine national dance) and Arnis (a Filipino style of martial arts) to create a contemporary combination of rhythm, dance, and fitness. It was designed to introduce…

  17. Field and temperature dependence of the small polaron hopping electrical conductivity in 1D disordered systems

    Energy Technology Data Exchange (ETDEWEB)

    Triberis, G P; Dimakogianni, M, E-mail: gtriber@phys.uoa.g [Solid State Section, Physics Department, University of Athens, Panepistimiopolis, 15784 Zografos, Athens (Greece)

    2009-09-23

    We investigate the effect of the electric field and the temperature on the electrical conductivity of one-dimensional disordered systems due to phonon assisted hopping of small polarons. The microscopic transport mechanism is treated within the framework of the generalized molecular crystal model and the Kubo formula, while percolation theoretical arguments lead to analytical expressions for the macroscopic behavior of the electrical conductivity at high (multi-phonon assisted hopping) and low (few-phonon assisted hopping) temperatures under the influence of moderate electric fields. The theoretical results are successfully applied to recent experimental findings for a wide temperature range and from low up to moderate electric fields. Comparison is made with other theories.

  18. Coherent optical time domain reflectometry by logarithmic detection and timed random frequency hopping

    Science.gov (United States)

    Lu, Lidong; Sun, Xiaoyan; Bu, Xiande; Li, Binglin

    2017-02-01

    A scheme using timed random frequency hopping and signal logarithmic mean method is proposed and experimentally demonstrated in a coherent optical time domain reflectometry (OTDR) system to reduce the fading noise of the OTDR trace and simplify the signal processing procedure. The timed random frequency hopping is realized by randomly changing the driving current of the laser at certain time points. By this method, the fading noise of OTDR trace can be reduced to be 1/5 of that without using it. Also, a radio frequency power detector (RFPD), whose output voltage has linear relationship with the input logarithmic RF power, is used to extract the power of the RF signals from the balanced photodetector. Then, a data acquisition card directly captures and adds the digital voltage signals from the RFPD to reduce the fading noise and improve the measurement dynamic range. Compared with synchronous and asynchronous frequency hopping scheme, the proposed method is of high efficiency.

  19. Featherless Dinosaurs and the Hip-Hop Simulacrum: Reconsidering Hip-Hop's Appropriateness for the Music Classroom

    Science.gov (United States)

    Kruse, Adam J.

    2016-01-01

    This article offers considerations for music teachers interested in including hip-hop music in their classrooms but who might feel concerned with or overwhelmed by issues of appropriateness. Two concerns related to hip-hop music are examined: language and negative social themes. Commercial interests in hip-hop music have created a simulacrum (or…

  20. Hop-by-hop Content Distribution with Network Coding in Multihop Wireless Networks

    Directory of Open Access Journals (Sweden)

    Rami Halloush

    2017-02-01

    Full Text Available The predominant use of today's networks is content access and distribution. Network Coding (NC is an innovative technique that has potential to improve the efficiency of multicast content distribution over multihop Wireless Mesh Networks (WMNs by allowing intermediate Forwarding Nodes (FNs to encode and then forward data packets. Practical protocols are needed to realize the benefits of the NC technique. However, the existing NC-based multicast protocols cannot accurately determine the minimum number of coded packets that a FN should send in order to ensure successful data delivery to the destinations, so that many redundant packets are injected into the network, leading to performance degradation. In this paper, we propose HopCaster, a novel reliable multicast protocol that incorporates network coding with hop-by-hop transport. HopCaster completely eliminates the need for estimating the number of coded packets to be transmitted by a FN, and avoids redundant packet transmissions. It also effectively addresses the challenges of heterogeneous multicast receivers. Moreover, a cross-layer multicast rate adaptation mechanism is proposed, which enables HopCaster to optimize multicast throughput by dynamically adjusting wireless transmission rate based on the changes in the receiver population and channel conditions during the course of multicasting a coded data chunk. Our evaluations show that HopCaster significantly outperforms the existing NC-based multicast protocols.

  1. Interference in Joint Picture Naming

    Science.gov (United States)

    Gambi, Chiara; Van de Cavey, Joris; Pickering, Martin J.

    2015-01-01

    In 4 experiments we showed that picture naming latencies are affected by beliefs about the task concurrently performed by another speaker. Participants took longer to name pictures when they believed that their partner concurrently named pictures than when they believed their partner was silent (Experiments 1 and 4) or concurrently categorized the…

  2. The polycentric picture

    DEFF Research Database (Denmark)

    Flensborg, Ingelise

    2008-01-01

    The polycentric picture The presentation introduces a dynamic view on children's drawings inspired by J.J.Gibson's ecological approach to visual perception. Empirical research in children's drawings will be the basis for the documentation of the fact that children's drawings contain several...... strategies of vision, which can be activated, re-established and differentiated in relation to dynamic media productions. The significance of spatial orientation to our ability to see and to the way we are seeing is focused and a concept of the ex-centric observer is introduced....

  3. Global Ill-Literacies: Hip Hop Cultures, Youth Identities, and the Politics of Literacy

    Science.gov (United States)

    Alim, H. Samy

    2011-01-01

    This article focuses on the emergence of what the author refers to as "global ill-literacies," that is, the hybrid, transcultural linguistic and literacy practices of Hip Hop youth in local and global contexts, as well as the pedagogical possibilities that scholars open up as they engage these forms. By reviewing a broad but focused range of…

  4. Leg stiffness primarily depends on ankle stiffness during human hopping.

    Science.gov (United States)

    Farley, C T; Morgenroth, D C

    1999-03-01

    When humans hop in place or run forward, they adjust leg stiffness to accommodate changes in stride frequency or surface stiffness. The goal of the present study was to determine the mechanisms by which humans adjust leg stiffness during hopping in place. Five subjects hopped in place at 2.2 Hz while we collected force platform and kinematic data. Each subject completed trials in which they hopped to whatever height they chose ("preferred height hopping") and trials in which they hopped as high as possible ("maximum height hopping"). Leg stiffness was approximately twice as great for maximum height hopping as for preferred height hopping. Ankle torsional stiffness was 1.9-times greater while knee torsional stiffness was 1.7-times greater in maximum height hopping than in preferred height hopping. We used a computer simulation to examine the sensitivity of leg stiffness to the observed changes in ankle and knee stiffness. Our model consisted of four segments (foot, shank, thigh, head-arms-trunk) interconnected by three torsional springs (ankle, knee, hip). In the model, increasing ankle stiffness by 1.9-fold, as observed in the subjects, caused leg stiffness to increase by 2.0-fold. Increasing knee stiffness by 1.7-fold had virtually no effect on leg stiffness. Thus, we conclude that the primary mechanism for leg stiffness adjustment is the adjustment of ankle stiffness.

  5. On a general class of quadratic hopping sequences

    Institute of Scientific and Technical Information of China (English)

    JIA HuaDing; YUAN Ding; PENG DaiYuan; GUO Ling

    2008-01-01

    Based upon quadratic polynomials over the finite field, a new class of frequency hopping sequences with large family size suitable for applications in time/frequency hopping CDMA systems, multi-user radar and sonar systems is proposed and investigated. It is shown that the new time/frequency hopping sequences have at most one hit in their autocorrelation functions and at most two hits in their crosscorrelation functions except for a special case, and their family size is much larger than the conventional quadratic hopping sequences. The percentage of full collisions for the new quadratic hopping sequences is discussed. In addition, the average number of hits for the new quadratic hopping sequences, quadratic congruence sequences, extended quadratic congruence sequences and the general linear hopping sequences are also derived.

  6. Communication: Global flux surface hopping in Liouville space

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Linjun, E-mail: linjun.wang@usc.edu, E-mail: prezhdo@usc.edu; Prezhdo, Oleg V., E-mail: linjun.wang@usc.edu, E-mail: prezhdo@usc.edu [Department of Chemistry, University of Southern California, Los Angeles, California 90089-1062 (United States); Sifain, Andrew E. [Department of Physics and Astronomy, University of Southern California, Los Angeles, California 90089-0485 (United States)

    2015-11-21

    Recent years have witnessed substantial progress in the surface hopping (SH) formulation of non-adiabatic molecular dynamics. A generalization of the traditional fewest switches SH (FSSH), global flux SH (GFSH) utilizes the gross population flow between states to derive SH probabilities. The Liouville space formulation of FSSH puts state populations and coherences on equal footing, by shifting the hopping dynamics from Hilbert to Liouville space. Both ideas have shown superior results relative to the standard FSSH in Hilbert space, which has been the most popular approach over the past two and a half decades. By merging the two ideas, we develop GFSH in Liouville space. The new method is nearly as straightforward as the standard FSSH, and carries comparable computational expense. Tested with a representative super-exchange model, it gives the best performance among all existing techniques in the FSSH series. The obtained numerical results match almost perfectly the exact quantum mechanical solutions. Moreover, the results are nearly invariant under the choice of a basis state representation for SH, in contrast to the earlier techniques which exhibit notable basis set dependence. Unique to the developed approach, this property is particularly encouraging, because exact quantum dynamics is representation independent. GFSH in Liouville space significantly improves accuracy and applicability of SH for a broad range of chemical and physical processes.

  7. Pictures of the month

    CERN Multimedia

    Claudia Marcelloni de Oliveira

    Starting with this issue, we will publish special pictures illustrating the ongoing construction and commissioning efforts. If you wish to have a professionnal photographer immortalize your detector before it disappears in the heart of ATLAS or for a special event, don't hesitate to contact Claudia Marcelloni de Oliveira (16-3687) from the CERN photo service. Members of the pixel team preparing to insert the outermost layer (the outer of the three barrel pixel layers) into the Global Support Frame for the Pixel Detector in SR1. Ongoing work on the first Big Wheel on the C side. Exploded view of the side-C Big Wheel and the barrel cryostat. The TRT Barrel services (HV, LV, cooling liquid, active gas, flushing gas) are now completely connected and tested. Hats off to Kirill Egorov, Mike Reilly, Ben Legeyt and Godwin Mayers who managed to fit everything within the small clearance margin!

  8. Nation's water picture mixed

    Science.gov (United States)

    The nation's water picture for April showed mixed trends: More than half of the index gaging stations reported normal streamflow conditions during the month, while the spring snowmelt boosted streamflow in the Northeast and Northwest to well above normal levels. Parts of the Southeast, however, from West Virginia south to the Carolinas, reported well-below normal streamflow conditions, according to a month-end check on water resources conditions by the U.S. Geological Survey, Department of the Interior.After nearly 2 years of drought conditions the three major reservoirs supplying New York City reached full storage capacity and were spilling during April. Combined contents of the three reservoirs on May 1, 1982, was 272 billion gallons, 101% of their full usable capacity. The full reservoirs and the generally good surface and groundwater conditions throughout the Delaware River basin allowed the Delaware River Basin Commission to lift its drought emergency warning on April 27.

  9. Landscape as World Picture

    DEFF Research Database (Denmark)

    Wamberg, Jacob

    Age, among the powers-that-be. The topic of Volume II is the breakthrough of the modern landscape image and its new perspectival vistas, transient time and cultivated - or completely deserted - terrains. This post-medieval paradigm shift is construed as the mature stage in the evolution of self......-consciousness, with an urban individual contemplating nature at an aesthetic distance. Apart from being structurally equivalent with the new Copernican cosmos and the colonial expansion of Western culture, the new territorial landscape image is shown to develop in close interaction with the early modern work ethic...... from Palaeolithic cave paintings through to 19th-century modernity. A structuralist comparison between this pattern and three additional fields of analysis - self-consciousness, socially-determined perception of nature, and world picture - reveals a fascinating insight into culture's macrohistorical...

  10. Landscape as World Picture

    DEFF Research Database (Denmark)

    Wamberg, Jacob

    -consciousness, with an urban individual contemplating nature at an aesthetic distance. Apart from being structurally equivalent with the new Copernican cosmos and the colonial expansion of Western culture, the new territorial landscape image is shown to develop in close interaction with the early modern work ethic......This book presents a new and comprehensive theory concerning the manner in which landscapes in Western pictorial art may be interpreted in relation to the cultures that created them. Its point of departure is a hitherto unexplored developmental pattern that characterises landscape representation...... from Palaeolithic cave paintings through to 19th-century modernity. A structuralist comparison between this pattern and three additional fields of analysis - self-consciousness, socially-determined perception of nature, and world picture - reveals a fascinating insight into culture's macrohistorical...

  11. Hierarchical Picture Coding Using Quadtree Decomposition

    Science.gov (United States)

    Buhler, Yves; Fortier, Michel

    1987-10-01

    A new hierarchical encoding scheme for grey-level pictures is presented here. The picture field is split by a modified quadtree algorithm into blocks of size 32 x 32, 16 x 16, 8 x 8 and 4 x 4 pels, according to their subjective importance in the picture. The larger cells, of size 32 x 32, 16 x 16 and 8 x 8 pels, corresponding to uniform or low-detailed areas, are coded at a very low rates by block truncation in the Discrete Cosine Transform field. The smallest blocks, representing mainly high-detailed areas of the like edges or textures are coded with a multi-codebook vector quantization scheme. Due to its structure, such an encoding scheme is especially well adapted for coding "head and shoulders" pictures, mostly encountered in videophone or videoconference application, where large areas of background may appear. Concerning the vector quantization, several techniques were investigated in order to improve the subjective quality and to reduce the search time through the codebooks. This permits a faster elaboration of the codebooks. Results are presented with bit-rates ranging from 0.4 to 0.8 bits/pel depending on the picture complexity.

  12. Evaluation of airborne methyl salicylate for improved conservation biological control of two-spotted spider mite and hop aphid in Oregon hop yards.

    Science.gov (United States)

    Woods, J L; James, D G; Lee, J C; Gent, D H

    2011-12-01

    The use of synthetic herbivore-induced plant volatiles (HIPV) to attract natural enemies has received interest as a tool to enhance conservation biological control (CBC). Methyl salicylate (MeSA) is a HIPV that is attractive to several key predators of two-spotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), and hop aphid, Phorodon humuli (Schrank) (Homoptera: Aphididae). A 2-year study was conducted to evaluate the recommended commercial use of MeSA in hop yards in Oregon. Slow-release MeSA dispensers were stapled to supporting poles in 0.5 ha plots and these plots were compared to a paired non-treated plot on each of three farms in 2008 and 2009. Across both years, there was a trend for reduced (range 40-91%) mean seasonal numbers of T. urticae in five of the six MeSA-baited plots. Stethorus spp., key spider mite predators, tended to be more numerous in MeSA-baited plots compared to control plots on a given farm. Mean seasonal densities of hop aphid and other natural enemies (e.g., Orius spp. and Anystis spp.) were similar between MeSA-treated and control plots. Variability among farms in suppression of two-spotted spider mites and attraction of Stethorus spp. suggests that the use of MeSA to enhance CBC of spider mites in commercial hop yards may be influenced by site-specific factors related to the agroecology of individual farms or seasonal effects that require further investigation. The current study also suggests that CBC of hop aphid with MeSA in this environment may be unsatisfactory.

  13. Uudised : Pop-karneval. Hip-hop

    Index Scriptorium Estoniae

    2005-01-01

    Muusika- ja kunstikarnevalist "Beta Bubble" 1. apr. Tallinnas Von Krahlis. Pärnu taasühinenud hip-hop-bänd Noizmakaz (TommyBoy ja Alko) sõlmis lepingu plaadifirmaga Mindnote ja annab selle alt apr. keskel välja oma teise albumi "Valitud mõtted".1. apr. tuleb müügile Noizmakazi singel "Miski muu ei loe", debüüt "Social Poetry" ilmus aastal 2001

  14. Collision-based mechanics of bipedal hopping

    OpenAIRE

    Gutmann, Anne K.; Lee, David V; McGowan, Craig P.

    2013-01-01

    The muscle work required to sustain steady-speed locomotion depends largely upon the mechanical energy needed to redirect the centre of mass and the degree to which this energy can be stored and returned elastically. Previous studies have found that large bipedal hoppers can elastically store and return a large fraction of the energy required to hop, whereas small bipedal hoppers can only elastically store and return a relatively small fraction. Here, we consider the extent to which large and...

  15. Uudised : Pop-karneval. Hip-hop

    Index Scriptorium Estoniae

    2005-01-01

    Muusika- ja kunstikarnevalist "Beta Bubble" 1. apr. Tallinnas Von Krahlis. Pärnu taasühinenud hip-hop-bänd Noizmakaz (TommyBoy ja Alko) sõlmis lepingu plaadifirmaga Mindnote ja annab selle alt apr. keskel välja oma teise albumi "Valitud mõtted".1. apr. tuleb müügile Noizmakazi singel "Miski muu ei loe", debüüt "Social Poetry" ilmus aastal 2001

  16. Exploiting Multi-user Diversity and Multi-hop Diversity in Dual-hop Broadcast Channels

    KAUST Repository

    Zafar, Ammar

    2013-05-21

    We propose joint user-and-hop scheduling over dual-hop block-fading broadcast channels in order to exploit multi-user diversity gains and multi-hop diversity gains all together. To achieve this objective, the first and second hops are scheduled opportunistically based on the channel state information. The joint scheduling problem is formulated as maximizing the weighted sum of the long term achievable rates of the users under a stability constraint, which means that in the long term the rate received by the relay should equal the rate transmitted by it, in addition to power constraints. We show that this problem is equivalent to a single-hop broadcast channel by treating the source as a virtual user with an optimal weight that maintains the stability constraint. We show how to obtain the source weight either off-line based on channel statistics or on real-time based on channel measurements. Furthermore, we consider special cases including the maximum sum-rate scheduler and the proportional fair scheduler. We also show how to extend the scheme into one that allows multiple user scheduling via superposition coding with successive decoding. Numerical results demonstrate that our proposed joint scheduling scheme enlarges the rate region as compared to scheduling schemes that exploit the diversity gains partially.

  17. Photon assisted hopping conduction mechanism in Tl{sub 2}SSe crystals

    Energy Technology Data Exchange (ETDEWEB)

    Qasrawi, A.F., E-mail: atef.qasrawi@atilim.edu.tr [Departments of Mathematics and Physics, Arab American University, 240 Jenin (Palestinian Territory, Occupied); Group of Physics, Faculty of Engineering, Atilim University, 06836 Ankara (Turkey); Ziqan, Abdelhalim M.; Jazzar, Suha Kh. [Departments of Mathematics and Physics, Arab American University, 240 Jenin (Palestinian Territory, Occupied); Group of Physics, Faculty of Engineering, Atilim University, 06836 Ankara (Turkey); Gasanly, N.M. [Department of Physics, Middle East Technical University, 06800 Ankara (Turkey)

    2015-02-01

    In this article, the powder X-ray diffraction data and the dark and the photo-excited electrical conduction parameters of Tl{sub 2}SSe crystal are reported. The dark and photon excited electrical conduction in the tetragonal crystal are found to be dominated by thermionic emission assisted variable range hopping conduction (VRH). The dark Mott's VRH parameters representing by the degree of disorder (T{sub o}), the density of localized states near the Fermi level (N(E{sub F})), the average hopping range (R) and average hopping energy (W) exhibited wide tunability via incremental photon intensity. Particularly, while the dark values of T{sub 0},W and R significantly decreased from 2.32×10{sup 8} to 1.52×10{sup 5} K, 114 to 18.25 meV and from 66.15 to 10.58 A°, respectively, the values of N(E{sub F}) increased from 7.23×10{sup 18} to 1.10×10{sup 22}cm{sup −3}/eV when the crystal was photo-excited with a 53.6 mW/cm{sup 2} light intensity. These variations in the hopping parameters via photon excitations are promisig for using the crystal in the fabrication of well controlled, widely tunable, low energy consuming and highly efficient electronic devices.

  18. Painting Pictures with Whisky

    Science.gov (United States)

    Kim, Hyoungsoo; Boulogne, François; Um, Eujin; Jacobi, Ian; Stone, Howard

    2014-11-01

    Have you ever looked at the dried mark of whisky on the glass? While the whisky evaporates, various solid components inside the whisky are deposited with a peculiar pattern, which creates a beautiful picture. This particle patterning is induced by the solutal Marangoni effect. We investigate this effect on both the flow behavior and the particle deposition patterns in binary-mixture droplet evaporation by varying the concentration ratio between ethanol and water. To visualize the particle and fluid motion, we perform Particle Image Velocimetry. We observe that at the beginning stage complex circulating flow patterns occurred, which are triggered by the surface tension gradient, i.e. Marangoni effect. Ethanol first evaporates due to the lower vapor pressure compared to water. When the ethanol has vanished, a radial flow pattern is observed. Furthermore, we find that as the initial ethanol concentration increases, the mobility of the receding contact line increased. At high ethanol concentrations, the contact line kept receding so as to draw groups of particles that deposited in an annular pattern. We thank Ernie Button for sharing with us many beautiful images of whisky after it had dried.

  19. Rethinking Pedagogy in Urban Spaces: Implementing Hip-Hop Pedagogy in the Urban Science Classroom

    Science.gov (United States)

    Adjapong, Edmund S.; Emdin, Christopher

    2015-01-01

    A significant amount of research regarding Hip-Hop Based Education (HHBE) fails to provide insight on how to incorporate elements of Hip-Hop into daily teaching practices; rather Hip-Hop based educators focus mainly on incorporating Hip-Hop culture into curricula. This study explores the benefits of using two specific Hip-Hop pedagogical practices…

  20. Bounds on the hop domination number of a tree

    Indian Academy of Sciences (India)

    S K Ayyaswamy; B Krishnakumari; C Natarajan; Y B Venkatakrishnan

    2015-11-01

    A hop dominating set of a graph is a set of vertices of if for every vertex of () \\ D, there exists $u \\in D$ such that (, ) = 2. The hop domination number of a graph , denoted by ℎ(), is the minimum cardinality of a hop dominating set of . We prove that for every tree of order with leaves and support vertices we have (−− +4)/3 ≤ ℎ() ≤ /2, and characterize the trees attaining each of the bounds.

  1. Terrain dependant hop count selection for transparent relay transmissions

    Directory of Open Access Journals (Sweden)

    Cibile K. Kanjirathumkal

    2013-12-01

    Full Text Available In this Letter, the selection of the best hop count for a particular topography, in the context of enhanced connectivity using multi-hop transparent relay communication is addressed. Based on the coefficient of variation and the terrain specific fading severity factor of the distribution, it is possible to estimate the optimal hop count that can provide the required performance at detector. Two distribution models, which can adequately characterise the terrain fading effects on empirical data are considered for performance comparison. The results are useful in selecting branches, with low variability and optimal hop count for connectivity, in multi-stream switched diversity combining systems.

  2. Hopping Precession of Molecules in Crystalline Carbon Dioxide Films

    Science.gov (United States)

    Krainyukova, Nina; Kuchta, Bogdan

    2016-11-01

    We report a low-temperature transmission high-energy electron diffraction study of solid carbon dioxide films in the temperature range 15-87 K. The precise analysis of the experimental diffraction intensities shows that molecular axes noticeably deviate from the cubic space diagonals of the Paoverline{3} structure. The molecular tips tend to be oriented toward the empty spaces between two molecules in the nearest basal planes. Nevertheless, the crystal structure is still identified as Paoverline{3} but with 24 equivalent positions for oxygen atoms instead of 8 positions as it was thought before. We have shown that the relevant maximal angle deviations in the selected directions could be as big as ˜ 30° at the lowest temperatures and they decrease at higher temperature. This results in hopping precession of molecules instead of simple librations.

  3. Hopping Precession of Molecules in Crystalline Carbon Dioxide Films

    Science.gov (United States)

    Krainyukova, Nina; Kuchta, Bogdan

    2017-04-01

    We report a low-temperature transmission high-energy electron diffraction study of solid carbon dioxide films in the temperature range 15-87 K. The precise analysis of the experimental diffraction intensities shows that molecular axes noticeably deviate from the cubic space diagonals of the Paoverline{3} structure. The molecular tips tend to be oriented toward the empty spaces between two molecules in the nearest basal planes. Nevertheless, the crystal structure is still identified as Paoverline{3} but with 24 equivalent positions for oxygen atoms instead of 8 positions as it was thought before. We have shown that the relevant maximal angle deviations in the selected directions could be as big as {˜ } 30° at the lowest temperatures and they decrease at higher temperature. This results in hopping precession of molecules instead of simple librations.

  4. USING PICTURES IN ENGLISH CLASSES

    Institute of Scientific and Technical Information of China (English)

    1994-01-01

    Introduction In China, some English teachers go to class with only a textbook and a teaching plan, nothing else. After a while, the students complain that their classes are becoming more and more boring. Teachers have tried many ways to make their classes more interesting, motivating and effective, but using pictures in the classroom to do this has not been a popular method. The world provides us with all kinds of beautiful pictures. There is no reason why we should not make better use of them in language learning and teaching. This article will discuss the reasons for using pictures, suggest ways of collecting pictures and ways of using pictures in reading, writing, listening and speaking classes.

  5. Mortality in American Hip-Hop and Rap Recording Artists, 1987-2014.

    Science.gov (United States)

    Lawson, Carl J

    2015-12-01

    The deaths of American hip-hop and rap recording artists often receive considerable media attention. However, these artists' deaths have not been examined as a distinct group like the deaths of rock, classical, jazz, and pop music artists. This is a seminal epidemiological analysis on the deaths of an understudied group, American hip-hop and rap music recording artists. Media reports were analyzed of the deaths of American hip-hop and rap music recording artists that occurred from January 1, 1987 to December 31, 2014. The decedents' age, sex, race, cause of death, stage names, and city and state of death were recorded for analysis. The most commonly reported cause of death was homicide. The 280 deaths were categorized as homicide (55%), unintentional injury (13%), cardiovascular (7%), undetermined/undisclosed (7%), cancer (6%), other (5%), suicide (4%), and infectious disease (3%). The mean reported age at death was 30 yrs (range 15-75) and the median was 29 yrs; 97% were male and 92% were black. All but one of the homicides were committed with firearms. Homicide was the most commonly reported cause of death. Public health focus and guidance for hip-hop and rap recording artists should mirror that for African-American men and adolescent males ages 15-54 yrs, for whom the leading causes of death are homicide, unintentional injury, and heart disease. Given the preponderance of homicide deaths in this analysis, premature mortality reduction efforts should focus on violence prevention and conflict mitigation.

  6. Characterization of the Migration of Hop Volatiles into Different Crown Cork Liner Polymers and Can Coatings.

    Science.gov (United States)

    Wietstock, Philip C; Glattfelder, Richard; Garbe, Leif-Alexander; Methner, Frank-Jürgen

    2016-04-01

    Absorption of hop volatiles by crown cork liner polymers and can coatings was investigated in beer during storage. All hop volatiles measured were prone to migrate into the closures, and the absorption kinetics was demonstrated to fit Fick's second law of diffusion well for a plane sheet. The extent and rate of diffusion were significantly dissimilar and were greatly dependent upon the nature of the volatile. Diffusion coefficients ranged from 1.32 × 10(-5) cm(2)/day (limonene) to 0.26 × 10(-5) cm(2)/day (α-humulene). The maximum amounts absorbed into the material at equilibrium were in the following order: limonene > α-humulene > trans-caryophyllene > myrcene ≫ linalool > α-terpineol > geraniol. With the application of low-density polyethylene (LDPE) liners with oxygen-scavenging functionality, oxygen-barrier liners made up from high-density polyethylene (HDPE) or liner polymers from a different manufacturer had no significant effect on the composition of hop volatiles in beers after prolonged storage of 55 days; however, significantly higher amounts of myrcene and limonene were found in the oxygen-barrier-type crown cork, while all other closures behaved similarly. Can coatings were demonstrated to absorb hop volatiles in a similar pattern as crown corks but to a lesser extent. Consequently, significantly higher percentages of myrcene were found in the beers.

  7. High-Speed Hopping: Time-Resolved Tomographic PIV Measurements of Water Flea Swimming

    Science.gov (United States)

    Murphy, D. W.; Webster, D. R.; Yen, J.

    2012-11-01

    Daphniids, also known as water fleas, are small, freshwater crustaceans that live in a low-to-intermediate Reynolds number regime. These plankters are equipped with a pair of branched, setae-bearing antennae that they beat to impulsively propel themselves, or ``hop,'' through the water. A typical hop carries the daphniid one body length forward and is followed by a period of sinking. We present time-resolved tomographic PIV measurements of swimming by Daphnia magna. The body kinematics and flow physics of the daphniid hop are quantified. It is shown that the flow generated by each stroking antenna resembles an asymmetric viscous vortex ring. It is proposed that the flow produced by the daphniid hop can be modeled as a double Stokeslet consisting of two impulsively applied point forces separated by the animal width. The flow physics are discussed in the context of other species operating in the same Reynolds number range of 10 to 100: sea butterfly swimming and flight by the smallest flying insects.

  8. Comparison of four extraction methods for analysis of volatile hop-derived aroma compounds in beer.

    Science.gov (United States)

    Richter, Tobias M; Eyres, Graham T; Silcock, Patrick; Bremer, Phil J

    2017-09-09

    The volatile organic compound profile in beer is derived from hops, malt, yeast, and interactions between the ingredients, making it very diverse and complex. Due to the range and diversity of the volatile organic compounds present, the choice of the extraction method is extremely important for optimal sensitivity and selectivity. This study compared four extraction methods for hop-derived compounds in beer late hopped with Nelson Sauvin. Extraction capacity and variation were compared for headspace solid phase micro extraction, stir bar sorptive extraction, headspace sorptive extraction, and solvent assisted flavour evaporation. Generally, stir bar sorptive extraction was better suited for acids, headspace sorptive extraction for esters and aldehydes, while headspace solid phase micro extraction was less sensitive overall, extracting 40% fewer compounds. Solvent assisted flavour evaporation with dichloromethane was not suitable for the extraction of hop-derived volatile organic compounds in beer, as the profile was strongly skewed towards alcohols and acids. Overall, headspace sorptive extraction found to be best suited, closely followed by stir bar sorptive extraction. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  9. Security for multi-hop wireless networks

    CERN Document Server

    Mahmoud, Mohamed M E A

    2014-01-01

    This Springer Brief discusses efficient security protocols and schemes for multi-hop wireless networks. It presents an overview of security requirements for these networks, explores challenges in securing networks and presents system models. The authors introduce mechanisms to reduce the overhead and identify malicious nodes that drop packets intentionally. Also included is a new, efficient cooperation incentive scheme to stimulate the selfish nodes to relay information packets and enforce fairness. Many examples are provided, along with predictions for future directions of the field. Security

  10. Optimal Hops-Based Adaptive Clustering Algorithm

    Science.gov (United States)

    Xuan, Xin; Chen, Jian; Zhen, Shanshan; Kuo, Yonghong

    This paper proposes an optimal hops-based adaptive clustering algorithm (OHACA). The algorithm sets an energy selection threshold before the cluster forms so that the nodes with less energy are more likely to go to sleep immediately. In setup phase, OHACA introduces an adaptive mechanism to adjust cluster head and load balance. And the optimal distance theory is applied to discover the practical optimal routing path to minimize the total energy for transmission. Simulation results show that OHACA prolongs the life of network, improves utilizing rate and transmits more data because of energy balance.

  11. Hip—hop Music嘻哈乐

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Hip—Hop(嘻哈)文化源于上世纪七十年代美国黑人的一种街头说唱文化。在几十年的时间内,Hip—Hop文化也由一开始的打碟、说唱乐、街舞、涂鸦四个基本单元发展到包括滑板、街头篮球等表演性质的体育运动。现已蔓延到世界各地,深受年轻人的喜爱和欢迎。

  12. Pictures in Pictures: Art History and Art Museums in Children's Picture Books

    Science.gov (United States)

    Yohlin, Elizabeth

    2012-01-01

    Children's picture books that recreate, parody, or fictionalize famous artworks and introduce the art museum experience, a genre to which I will refer as "children's art books," have become increasingly popular over the past decade. This essay explores the pedagogical implications of this trend through the family program "Picture Books and Picture…

  13. Behavioral modulation by mutilation pictures in women

    Directory of Open Access Journals (Sweden)

    Pereira M.G.

    2004-01-01

    Full Text Available Previous studies have shown that women are more emotionally expressive than men. It is unclear, however, if women are also more susceptible to the emotional modulation of behavior imposed by an affective stimulus. To investigate this issue, we devised a task in which female subjects performed six sequential trials of visual target detection following the presentation of emotional (mutilation and erotic or neutral pictures (domestic utensils and objects and compared the data obtained in the present study with those described in a previous study with male subjects. The experiment consisted of three blocks of 24 pictures and each block had an approximate duration of 4 min. Our sample consisted of 36 subjects (age range: 18 to 26 years and each subject performed all blocks. Trials following the presentation of mutilation pictures (283 ms had significantly slower reaction times than those following neutral (270 ms pictures. None of the trials in the "pleasant block" (271 ms was significantly different from those in the "neutral block". The increase in reaction time observed in the unpleasant block may be related in part to the activation of motivational systems leading to an avoidance behavior. The interference effect observed in this study was similar to the pattern previously described for men. Thus, although women may be more emotionally expressive, they were not more reactive to aversive stimuli than men, as measured by emotional interference in a simple reaction time task.

  14. Exploring Wordless Picture Books

    Science.gov (United States)

    Serafini, Frank

    2014-01-01

    Wordless picturebooks may be better defined by what they do contain--visually rendered narratives--rather than what they do not contain. This column challenges traditional ways of looking at wordless picturebooks and offers a few approaches for integrating wordless picturebooks into a wider range of classrooms, preschool through middle school.

  15. Collision-based mechanics of bipedal hopping.

    Science.gov (United States)

    Gutmann, Anne K; Lee, David V; McGowan, Craig P

    2013-08-23

    The muscle work required to sustain steady-speed locomotion depends largely upon the mechanical energy needed to redirect the centre of mass and the degree to which this energy can be stored and returned elastically. Previous studies have found that large bipedal hoppers can elastically store and return a large fraction of the energy required to hop, whereas small bipedal hoppers can only elastically store and return a relatively small fraction. Here, we consider the extent to which large and small bipedal hoppers (tammar wallabies, approx. 7 kg, and desert kangaroo rats, approx. 0.1 kg) reduce the mechanical energy needed to redirect the centre of mass by reducing collisions. We hypothesize that kangaroo rats will reduce collisions to a greater extent than wallabies since kangaroo rats cannot elastically store and return as high a fraction of the mechanical energy of hopping as wallabies. We find that kangaroo rats use a significantly smaller collision angle than wallabies by employing ground reaction force vectors that are more vertical and center of mass velocity vectors that are more horizontal and thereby reduce their mechanical cost of transport. A collision-based approach paired with tendon morphometry may reveal this effect more generally among bipedal runners and quadrupedal trotters.

  16. HopBase: A unified resource for Humulus genomics

    Science.gov (United States)

    Hop (Humulus lupulus L. var lupulus) is a plant of worldwide significance, used primarily for its’ bittering and flavoring in brewing beer. Studies on the medicinal properties of several unique compounds produced by hop has led to additional interest from pharmacy and healthcare industries as well a...

  17. Hop powdery mildew control through alteration of spring pruning practices

    Science.gov (United States)

    Since 1997, Podosphaera macularis, the causal agent of hop powdery mildew, has become a recurrent threat to hops in the Pacific Northwest because of the potential to reduce cone yield and quality. Disease management practices often involve preventative fungicide applications, but alternative approac...

  18. Hip Hop as Empowerment: Voices in El Alto, Bolivia

    Science.gov (United States)

    Tarifa, Ariana

    2012-01-01

    In response to neoliberal policies that have been in place since 1985, Bolivian young people have increasingly used hip hop music as a means of protest and to reclaim social and political participation. Hip hop in Latin America tells the story of the struggles that marginalized people have suffered, and speaks to the effects of international…

  19. Being Hip-Hop: Beyond Skills and Songs

    Science.gov (United States)

    Kruse, Adam J.

    2016-01-01

    In this article, I offer four principles relevant to hip-hop cultures (keep it real, flip the script, make some noise, and stay fresh) and explore how these principles might affect music classrooms. I argue that a music classroom that works to keep it real, flip the script, make some noise, and stay fresh might go beyond teaching hip-hop skills…

  20. Gap solitons in periodic Schrodinger lattice system with nonlinear hopping

    Directory of Open Access Journals (Sweden)

    Ming Cheng

    2016-10-01

    Full Text Available This article concerns the periodic discrete Schrodinger equation with nonlinear hopping on the infinite integer lattice. We obtain the existence of gap solitons by the linking theorem and concentration compactness method together with a periodic approximation technique. In addition, the behavior of such solutions is studied as $\\alpha\\to 0$. Notice that the nonlinear hopping can be sign changing.

  1. Hip Hop as Empowerment: Voices in El Alto, Bolivia

    Science.gov (United States)

    Tarifa, Ariana

    2012-01-01

    In response to neoliberal policies that have been in place since 1985, Bolivian young people have increasingly used hip hop music as a means of protest and to reclaim social and political participation. Hip hop in Latin America tells the story of the struggles that marginalized people have suffered, and speaks to the effects of international…

  2. [Hopping and superexchange mechanisms of charge transport to DNA].

    Science.gov (United States)

    Lakhno, V D; Sultanov, V B

    2003-01-01

    A theory for charge transport in nucleobase sequences was constructed in which the hole migration proceeds via hopping between guanines. Each hop over the adenine-thymine (A-T) bridge connecting neighboring guanines occurs by means of the superexchange mechanism. The experimental data and theoretical results for various types of nucleobase sequences are compared.

  3. Chicano Hip-Hop as Interethnic Contact Zone

    Science.gov (United States)

    McFarland, Pancho

    2008-01-01

    The critical study of rap music and hip-hop culture has the potential to expand Americans understanding of race and culture in the United States. Hip-hop culture as a multiracial, multiethnic phenomenon reveals the ways in which race relations over the past thirty years have become increasingly complex. The theories and concepts that they use to…

  4. Christian Hip Hop as Pedagogy: A South African Case Study

    Science.gov (United States)

    Abraham, Ibrahim

    2015-01-01

    Drawing on interviews with creators of Christian hip hop music in South Africa, this article demonstrates that this genre of popular music and youth culture is utilised as a form of pedagogy to transmit religious beliefs and values to contemporary youth. The pedagogical aspects of hip hop have been recognised in research on the topic, but the…

  5. Transport of hop aroma compounds across Caco-2 monolayers.

    Science.gov (United States)

    Heinlein, A; Metzger, M; Walles, H; Buettner, A

    2014-11-01

    Although being reported and used as a sedative remedy for several years, the bioactive principle of hop preparations is still not decisively clarified. Understanding absorption and transformation processes of potential physiologically active constituents is essential to evaluate the likeliness of biological effects on humans. Therefore, single hop aroma compounds as well as digestive transformation products thereof have been investigated in view of their human intestinal absorption, applying Caco-2 transport experiments as well as investigations on potential biotransformation processes. Selective and sensitive identification and quantification were thereby achieved by application of two-dimensional high resolution gas chromatography-mass spectrometry in conjunction with stable isotope dilution analysis, leading to the determination of apparent permeability values by different mathematical approaches considering sink and non-sink conditions. Overall, calculated permeability values ranged from 2.6 × 10(-6) to 1.8 × 10(-4) cm s(-1) with all mathematical approaches, indicating high absorption potential and almost complete bioavailability for all tested compounds with hydroxyl-functionalities. Considering this high permeability together with the high lipophilicity of these substances, a passive transcellular uptake route can be speculated. Investigated sesquiterpenes and β-myrcene showed flat absorption profiles while the investigated esters showed decreasing profiles. In view of the lipophilic and volatile nature of the investigated substances, special attention was paid to recovery and mass balance determination. Furthermore, in the course of the transport experiments of 1-octen-3-ol and 3-methyl-2-buten-1-ol, additional biotransformation products were observed, namely 3-octanone and 3-methyl-2-butenal, respectively. The absence of these additional substances in control experiments strongly indicates an intestinal first-pass metabolism of the

  6. Picturing Urban Green Attachments

    DEFF Research Database (Denmark)

    Blok, Anders; Meilvang, Marie Leth

    2015-01-01

    In this article, we explore the cultural-political tensions and ambiguities of urban ecology, by way of following how activists move and translate between ‘familiar’ and ‘public’ engagements in the green city. Empirically, we locate our exploration in and around Nordhavnen (The North Harbor...... in the plural’ in the city. In particular, we stress the role assumed in such engagements by various image-making practices, as means for activists to express, share and render publicly visible a range of embodied urban attachments. Pragmatic sociology, we conclude, may contribute to a novel understanding...

  7. Hops (Humulus lupulus L. Bitter Acids: Modulation of Rumen Fermentation and Potential As an Alternative Growth Promoter

    Directory of Open Access Journals (Sweden)

    Michael D. Flythe

    2017-08-01

    Full Text Available Antibiotics can improve ruminant growth and efficiency by altering rumen fermentation via selective inhibition of microorganisms. However, antibiotic use is increasingly restricted due to concerns about the spread of antibiotic-resistance. Plant-based antimicrobials are alternatives to antibiotics in animal production. The hops plant (Humulus lupulus L. produces a range of bioactive secondary metabolites, including antimicrobial prenylated phloroglucinols, which are commonly called alpha- and beta-acids. These latter compounds can be considered phyto-ionophores, phytochemicals with a similar antimicrobial mechanism of action to ionophore antibiotics (e.g., monensin, lasalocid. Like ionophores, the hop beta-acids inhibit rumen bacteria possessing a classical Gram-positive cell envelope. This selective inhibition causes several effects on rumen fermentation that are beneficial to finishing cattle, such as decreased proteolysis, ammonia production, acetate: propionate ratio, and methane production. This article reviews the effects of hops and hop secondary metabolites on rumen fermentation, including the physiological mechanisms on specific rumen microorganisms, and consequences for the ruminant host and ruminant production. Further, we propose that hop beta-acids are useful model natural products for ruminants because of (1 the ionophore-like mechanism of action and spectrum of activity and (2 the literature available on the plant due to its use in brewing.

  8. Anderson localization in one-dimensional quasiperiodic lattice models with nearest- and next-nearest-neighbor hopping

    Science.gov (United States)

    Gong, Longyan; Feng, Yan; Ding, Yougen

    2017-02-01

    We explore the reduced relative Shannon information entropies SR for a quasiperiodic lattice model with nearest- and next-nearest-neighbor hopping, where an irrational number is in the mathematical expression of incommensurate on-site potentials. Based on SR, we respectively unveil the phase diagrams for two irrationalities, i.e., the inverse bronze mean and the inverse golden mean. The corresponding phase diagrams include regions of purely localized phase, purely delocalized phase, pure critical phase, and regions with mobility edges. The boundaries of different regions depend on the values of irrational number. These studies present a more complete picture than existing works.

  9. HRCT: hop-by-hop rate control technique for congestion control in wireless sensor network

    Science.gov (United States)

    Chakravarthi, Rekha; Cidambaram, Gomathy

    2011-12-01

    In Wireless Sensor Networks, congestion occurs when the traffic rate is high. This happens when the an event is detected in a network. Congestion causes packet loss thus degrading the performance of the network. Hence it necessitates to develop an effective congestion control technique. This paper focuses on congestion due to concurrent transmission. We have proposed an efficient protocol to detect and control congestion in a MAC. The occurrence of congestion is detected by calculating a new metrics called congestion scale. When the congestion scale exceeds the threshold value it intimates, that, congestion has occurred. Congestion notification signal is send to all the nodes. On receiving the notification signal all nodes adjust their transmission rate to control congestion. We have implemented Hop-by-Hop Rate Control Technique(HRCT) to control congestion and to guarantee both high throughput and minimum delay. This technique is implemented successfully in NS-2 simulator. Finally, simulation results have demonstrated the effectiveness of our proposed algorithm.

  10. Wifi, WiMax and LTE multi-hop mesh networks basic communication protocols and application areas

    CERN Document Server

    Wei, Hung-Yu; Dixit, Sudhir

    2013-01-01

    Wifi, WiMAX, and Cellular Multihop Networks presents an overview of WiFi-based and WiMAX-based multihop relay networks. As the first text to cover IEEE 802.16j multihop hop relay technology, this revolutionary resource explores the latest advances in multi-hop and ad-hoc networking. Not only does this reference provide the technological aspects, but also the applications for the emerging technology and architectural issues. Ranging from introductory material to advanced topics, this guidebook, plus PowerPoint slides, is essential for engineers, researchers, and students interested in

  11. Jahn-Teller assisted polaronic hole hopping as a charge transport mechanism in CuO nanograins

    Science.gov (United States)

    Younas, M.; Nadeem, M.; Idrees, M.; Akhtar, M. J.

    2012-04-01

    Impedance spectroscopy has been employed to investigate the dielectric and electric transport phenomena in sol-gel synthesized CuO nanograins. Semiconducting features of the grains and grain boundaries have been endorsed to the thermal activation of the localized charge carriers. On cooling below 303 K, a transition from Jahn-Teller polaron hopping mechanism to the Mott's variable range hopping mechanism has been observed owing to random potential fluctuations among localized sites. Activation energies for conduction and relaxation processes at grain boundaries provide strong signatures for the involvement of Jahn-Teller adiabatic small polarons as a charge transport mechanism in CuO nanograins.

  12. Report on Information Literacy and the Mic: Teaching Higher Education Students Critical Research Skills Using Hip Hop Lyricism

    Directory of Open Access Journals (Sweden)

    Walker, Dara

    2008-01-01

    Full Text Available Many professors expect undergraduate students to have basic research skills. However, they soon lear that their students are unable to find, sort, and analyze information for research papers and projects. To help students attain these skills, university librarians develop course-related information literacy (IL sessions for both undergraduate and graduate classes. In this study, I explored the differences and similarities in the objectives, teaching aides, ad final assignments of information literacy instruction which uses the thematic content in conscious hip hop lyricism to reinforce skills learned as compared to other methods. Understanding the differences and similarities may encourage librarians to make instruction through hip hop a part of their repertoire. The similarities express hip hop's ability to join the range of other methods while the differences point to the many contributions it can make to the current array of techniques.

  13. Communication devices for network-hopping communications and methods of network-hopping communications

    Science.gov (United States)

    Buttles, John W

    2013-04-23

    Wireless communication devices include a software-defined radio coupled to processing circuitry. The system controller is configured to execute computer programming code. Storage media is coupled to the system controller and includes computer programming code configured to cause the system controller to configure and reconfigure the software-defined radio to operate on each of a plurality of communication networks according to a selected sequence. Methods for communicating with a wireless device and methods of wireless network-hopping are also disclosed.

  14. MILITARY MULTI-HOP ROUTING PROTOCOL

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Military tactical network is one of the most important applications of ad hoc network. Currently the existing routing protocols are put forward based on the simple and universal network model which has the ability of multi-hop routing but cannot work efficiently in the special military applications. The narrow bandwidth and limited energy of the wireless network make general routing protocols seem to be more redundant.In order to satisfy military needs properly, this letter makes a detailed analysis of physical nodes and traffic distribution in military network, uses cross-layer design concept for reference, combines traffic characteristic of application layer with routing protocol design. It categorized routing problem as crucial routes and non-crucial routes which adopted separate maintenance methods. It not only realizes basic transmission function but also works efficiently. It is quite fit for military application.

  15. Direct current hopping conductance along DNA chain

    Institute of Scientific and Technical Information of China (English)

    Ma Song-Shan; Xu Hui; Liu Xiao-Liang; Li Ming-Jun

    2007-01-01

    This paper proposes a model of direct current(DC) electron hopping transport in DNA,in which DNA is considered as a binary one-dimensional disordered system.To quantitatively study the DC conductivity in DNA,it numerically calculates the DC conductivity of DNA chains with difierent parameter values.The result shows that the DC conductivity of DNA chain increases with the increase of temperature.And the conductivity of DNA chain is depended on the probability P.which represents the degree of compositional disorder in a DNA sequence to some extent.For P<0.5,the conductivity of DNA chain decreases with the increase of P,while for P≥0.5,the conductivity increases with the increase of p.The DC conductivity in DNA chain also varies with the change of the electric field,it presents non-Ohm's law conductivity characteristics.

  16. Capturing dynamic cation hopping in cubic pyrochlores

    Science.gov (United States)

    Brooks Hinojosa, Beverly; Asthagiri, Aravind; Nino, Juan C.

    2011-08-01

    In direct contrast to recent reports, density functional theory predicts that the most stable structure of Bi2Ti2O7 pyrochlore is a cubic Fd3¯m space group by accounting for atomic displacements. The displaced Bi occupies the 96g(x,x,z) Wyckoff position with six equivalent sites, which create multiple local minima. Using nudged elastic band method, the transition states of Bi cation hopping between equivalent minima were investigated and an energy barrier between 0.11 and 0.21 eV was determined. Energy barriers associated with the motion of Bi between equivalent sites within the 96g Wyckoff position suggest the presence of dielectric relaxation in Bi2Ti2O7.

  17. Distribution Function of Mesoscopic Hopping Conductance

    Institute of Scientific and Technical Information of China (English)

    何立群; Eugene Kogan; ,Moshe Kaveh; Shlomo Havlin; Nehemia Schartz; LUO Dawei

    2002-01-01

    We study mesoscopic hopping conductance by computer simulation distribution functions (DFs). It is found that the distributions obtained by choosing randomly the chemical potentials (for a fixed impurity configuration), which corresponds to a typical experimental situation, coincide with those obtained when both impurity configuration and chemical potential are chosen randomly, in agreement with the ergodicity hypothesis. The DFs in shape obtained for one-dimensional systems are found to be quite close to the predictions of the theory by Raikh and Ruzin. For the two-dimensional case, the DFs both for a narrow system and thin film look to be similar (and close to the one-dimensional case). The DF for the conductance of the square sample is nearly Gaussian.

  18. Bit-padding information guided channel hopping

    KAUST Repository

    Yang, Yuli

    2011-02-01

    In the context of multiple-input multiple-output (MIMO) communications, we propose a bit-padding information guided channel hopping (BP-IGCH) scheme which breaks the limitation that the number of transmit antennas has to be a power of two based on the IGCH concept. The proposed scheme prescribes different bit-lengths to be mapped onto the indices of the transmit antennas and then uses padding technique to avoid error propagation. Numerical results and comparisons, on both the capacity and the bit error rate performances, are provided and show the advantage of the proposed scheme. The BP-IGCH scheme not only offers lower complexity to realize the design flexibility, but also achieves better performance. © 2011 IEEE.

  19. Method development and fate determination of pesticide-treated hops and their subsequent usage in the production of beer.

    Science.gov (United States)

    Hengel, Matt J; Shibamoto, Takayuki

    2002-06-05

    The fate of residues of seven agrochemicals (chlorfenapyr, quinoxyfen, tebuconazole, fenarimol, pyridaben, and E- and Z-dimethomorph) from the treatment on hops to the brewing of beer was studied. First, a multi-residue analytical method was developed for the determination of pesticide residues in spent hops, trub, wort, and beer. Each matrix was validated over at least two levels of fortification, for all seven compounds, in the ranges 0.05-5.0, 0.001-1.0, 0.001-0.05, and 0.0005-1.0 ppm for spent hops, trub, wort, and beer, respectively. Recoveries ranged from 73 to 136%. Second, the matrixes prepared from hops, which were treated under commercial practices with each compound, were analyzed using the method developed. The use of treated hops resulted in the carryover of 0.001 ppm of tebuconazole, 0.008 Z-dimethomorph, and 0.005 ppm of E-dimethomorph into the wort. The bulk of the remaining residues of all seven compounds was found on the spent hops. Following fermentation, all compounds were found in levels less than 0.0005 ppm in beer, except Z- (0.006 ppm) and E-dimethomorph (0.004 ppm). Third, when all seven pesticides were spiked prior to the pitching of yeast into clean wort, most of the nonpolar compounds (chlorfenapyr, quinoxyfen, and pyridaben) partitioned into the organic material (trub) which settled to the bottom, while the more polar compounds (fenarimol, tebuconazole, and E- and Z-dimethomorph) were generally distributed evenly between the beer and the trub.

  20. Non-adiabatic dynamics close to conical intersections and the surface hopping perspective

    Directory of Open Access Journals (Sweden)

    João Pedro eMalhado

    2014-11-01

    Full Text Available Conical intersections play a major role in the current understanding of electronic de-excitation in polyatomic molecules, and thus in the description of photochemistry and photo physics of molecular systems. This article reviews aspects of the basic theory underlying the description of non-adiabatic transitions at conical intersections, with particular emphasis on the important case when the dynamics of the nuclei are treated classically. Within this classical nuclear motion framework, the main aspects of the surface hopping methodology in the conical intersection context are presented. The emerging picture from this treatment is that of electronic transitions around conical intersections dominated by the interplay of the nuclear velocity and the derivative non-adiabatic coupling vector field.

  1. Multi-Hop Bandwidth Management Protocol for Mobile Ad Hoc Networks

    CERN Document Server

    Pattanayak, Binod Kumar; Jagadev, Alok Kumar; Nayak, Manojranjan

    2010-01-01

    An admission control scheme should play the role of a coordinator for flows in a data communication network, to provide the guarantees as the medium is shared. The nodes of a wired network can monitor the medium to know the available bandwidth at any point of time. But, in wireless ad hoc networks, a node must consume the bandwidth of neighboring nodes, during a communication. Hence, the consumption of bandwidth by a flow and the availability of resources to any wireless node strictly depend upon the neighboring nodes within its transmission range. We present a scalable and efficient admission control scheme, Multi-hop Bandwidth Management Protocol (MBMP), to support the QoS requirements in multi-hop ad hoc networks. We simulate several options to design MBMP and compare the performances of these options through mathematical analysis and simulation results, and compare its effectiveness with the existing admission control schemes through extensive simulations. KEYWORDS

  2. A Low-Cost Time-Hopping Impulse Radio System for High Data Rate Transmission

    Directory of Open Access Journals (Sweden)

    Jinyun Zhang

    2005-03-01

    Full Text Available We present an efficient, low-cost implementation of time-hopping impulse radio that fulfills the spectral mask mandated by the FCC and is suitable for high-data-rate, short-range communications. Key features are (i all-baseband implementation that obviates the need for passband components, (ii symbol-rate (not chip rate sampling, A/D conversion, and digital signal processing, (iii fast acquisition due to novel search algorithms, and (iv spectral shaping that can be adapted to accommodate different spectrum regulations and interference environments. Computer simulations show that this system can provide 110 Mbps at 7–10 m distance, as well as higher data rates at shorter distances under FCC emissions limits. Due to the spreading concept of time-hopping impulse radio, the system can sustain multiple simultaneous users, and can suppress narrowband interference effectively.

  3. Conductivity analysis of epoxy/carbon nanotubes composites by dipole relaxation and hopping models

    Science.gov (United States)

    Ramos, Airton; Pezzin, Sergio H.; Farias, Heric Denis; Becker, Daniela; Bello, Roger H.; Coelho, Luiz A. F.

    2016-10-01

    In this study it was used a numerical technique of successive approximations to estimate parameters of a conductivity model that includes the hopping process and the dipole relaxation for the purpose of describing the behavior of the conductivity measured on nanocomposites with carbon nanotubes in epoxy resin in the range of frequency of 100 Hz to 40 MHz. Two relaxation bands were detected, one with a response below 10 kHz and one above 10 MHz. For the first band, it was observed that the nanocomposites become more conductive, and its conductivity less temperature dependent, as the nanotube content increases. The second band is characterized by a large spread in relaxation time. The results show that the percolation threshold is below 0.15 vol% and that 'ac' hopping is the main transport process above 100 kHz, becoming dominant with respect to percolation at higher temperatures (>340 K).

  4. Bianisotropy Picture of Higher Permeability at Higher Frequencies

    Institute of Scientific and Technical Information of China (English)

    XUE De-Sheng; LI Fa-Shen; FAN Xiao-Long; WEN Fu-Sheng

    2008-01-01

    With an effective bianisotropy picture, high-frequency behaviours of different magnetic materials can be reconciled, and the higher permeability and higher resonance frequencies are achieved even in the GHz range. The validity of the bianisotropy picture is quantitatively refilled by the in-plane anisotropic Fe34Co55Zr11 thin films.A prolate elliptical precession of the magnetization about its equilibrium direction is the key point, which can be induced by an artificial or an intrinsic bianisotropy system.

  5. Let Me Blow Your Mind: Hip Hop Feminist Futures in Theory and Praxis

    Science.gov (United States)

    Lindsey, Treva B.

    2015-01-01

    This essay brings together key theoretical interventions in hip-hop feminism to explore the continued, but undervalued, significance of hip-hop feminism in urban education. More specifically, the essay challenges narrow conceptualizations of the "hip hop subject" as Black and male by using hip-hop feminist theory to incorporate the lived…

  6. Characterization of hop pectins shows the presence of an arabinogalactan-protein

    NARCIS (Netherlands)

    Oosterveld, A.; Voragen, A.G.J.; Schols, H.A.

    2002-01-01

    Hop pectins were extracted from spent hops using acid extraction conditions and were characterized chemically. The acid extraction of spent hops resulted in a yield of 2°containing 59 f polysaccharides. The hop pectins under investigation had a relatively high molecular weight and an intrinsic visco

  7. Let Me Blow Your Mind: Hip Hop Feminist Futures in Theory and Praxis

    Science.gov (United States)

    Lindsey, Treva B.

    2015-01-01

    This essay brings together key theoretical interventions in hip-hop feminism to explore the continued, but undervalued, significance of hip-hop feminism in urban education. More specifically, the essay challenges narrow conceptualizations of the "hip hop subject" as Black and male by using hip-hop feminist theory to incorporate the lived…

  8. Mic Power? Connections and the hip hop nation in Kampala, Uganda

    DEFF Research Database (Denmark)

    Schneidermann, Nanna

    2014-01-01

    Hip hop culture has been celebrated in the media and scholarship as a universal youth language, part of a global hip hop nation, and a type of counter-public. This article examines the everyday meanings and practices of hip hop among hip hop activists in Kampala, Uganda, specifically within the B...

  9. Determinants of Job Hopping Experience among Private and Public ...

    African Journals Online (AJOL)

    Determinants of Job Hopping Experience among Private and Public Sector ... AFRICAN JOURNALS ONLINE (AJOL) · Journals · Advanced Search · USING AJOL ... This study investigated perceived organizational justice, job stress and job ...

  10. Hip Hop Dance Experience Linked to Sociocognitive Ability

    National Research Council Canada - National Science Library

    Justin W Bonny; Jenna C Lindberg; Marc C Pacampara

    2017-01-01

    .... In the present study, we examined whether experience in a different activity, hip hop dance, is also linked to cognitive abilities connected with STEM skills as well as social cognition ability...

  11. Hopping trajectory optimization for surface exploration on small bodies

    Science.gov (United States)

    Liu, Yanjie; Zhu, Shengying; Cui, Pingyuan; Yu, Zhengshi; Zong, Hua

    2017-07-01

    Surface exploration is an important way to improve the understanding of small bodies. Considering the irregular and weak gravity field near a small body, the movement of the surface explorer is generally achieved by hopping. In this paper, a guidance algorithm method based on convex optimization approach for pinpoint hopping movement on a small body is developed in order to improve the stability and accuracy of surface exploration. We formulate a fuel-optimal control problem for the single pinpoint hopping and convert it into a second-order cone programming (SOCP) problem which can be solved effectively by primal-dual-interior points method. A multi-hopping scenario is also proposed for the long-distance transfer. To certificate the performance of the proposed guidance algorithm, a full set of simulations are conducted and the effectiveness are analyzed.

  12. Potential African Substitutes for Hops in Tropical Beer Brewing

    African Journals Online (AJOL)

    These values however decreased, the longer the storage period. Losses in bitterness ... Key words: Hops, Resins, Essential Oils, Bitterness level. ... tight transparent glass bottle and then ... measured. ..... contact with oxygen and also the rate.

  13. SOFTWARE SUPPORT FOR RICH PICTURES

    DEFF Research Database (Denmark)

    Valente, Andrea; Marchetti, Emanuela

    2010-01-01

    Rich pictures (RP) are common in object-oriented analysis and design courses, but students seem to have problems in integrating them in their projects' workflow. A new software tool is being developed, specific for RP authoring. To better understand students' issues and working practice with RP...

  14. The Picture of Dorian Gray

    NARCIS (Netherlands)

    Wilde, Oscar

    2005-01-01

    On its first publication The Picture of Dorian Gray was regarded as dangerously modern in its depiction of fin-de-sicle decadence. In this updated version of the Faust story, the tempter is Lord Henry Wotton, who lives selfishly for amoral pleasure; Dorian's good angel is the portrait painter Basil

  15. On the Color Dipole Picture

    CERN Document Server

    Schildknecht, Dieter

    2016-01-01

    We give a brief representation of the theoretical results from the color dipole picture, covering the total photoabsorption cross section, high-energy $J/\\psi$ photoproduction with respect to recent experimental data from the LHCb Collaboration at CERN, and ultra-high energy neutrino scattering, relevant for the ICE-CUBE experiment.

  16. The Picture of Dorian Gray

    NARCIS (Netherlands)

    Wilde, Oscar

    2005-01-01

    On its first publication The Picture of Dorian Gray was regarded as dangerously modern in its depiction of fin-de-sicle decadence. In this updated version of the Faust story, the tempter is Lord Henry Wotton, who lives selfishly for amoral pleasure; Dorian's good angel is the portrait painter Basil

  17. Leg exoskeleton reduces the metabolic cost of human hopping.

    Science.gov (United States)

    Grabowski, Alena M; Herr, Hugh M

    2009-09-01

    During bouncing gaits such as hopping and running, leg muscles generate force to enable elastic energy storage and return primarily from tendons and, thus, demand metabolic energy. In an effort to reduce metabolic demand, we designed two elastic leg exoskeletons that act in parallel with the wearer's legs; one exoskeleton consisted of a multiple leaf (MLE) and the other of a single leaf (SLE) set of fiberglass springs. We hypothesized that hoppers, hopping on both legs, would adjust their leg stiffness while wearing an exoskeleton so that the combination of the hopper and exoskeleton would behave as a linear spring-mass system with the same total stiffness as during normal hopping. We also hypothesized that decreased leg force generation while wearing an exoskeleton would reduce the metabolic power required for hopping. Nine subjects hopped in place at 2.0, 2.2, 2.4, and 2.6 Hz with and without an exoskeleton while we measured ground reaction forces, exoskeletal compression, and metabolic rates. While wearing an exoskeleton, hoppers adjusted their leg stiffness to maintain linear spring-mass mechanics and a total stiffness similar to normal hopping. Without accounting for the added weight of each exoskeleton, wearing the MLE reduced net metabolic power by an average of 6% and wearing the SLE reduced net metabolic power by an average of 24% compared with hopping normally at frequencies between 2.0 and 2.6 Hz. Thus, when hoppers used external parallel springs, they likely decreased the mechanical work performed by the legs and substantially reduced metabolic demand compared with hopping without wearing an exoskeleton.

  18. Transport of hop aroma compounds across Caco-2 monolayers

    OpenAIRE

    Heinlein, A.; Metzger, M.; Walles, H.; Buettner, A.

    2014-01-01

    Although being reported and used as a sedative remedy for several years, the bioactive principle of hop preparations is still not decisively clarified. Understanding absorption and transformation processes of potential physiologically active constituents is essential to evaluate the likeliness of biological effects on humans. Therefore, single hop aroma compounds as well as digestive transformation products thereof have been investigated in view of their human intestinal absorption, applying ...

  19. Role of correlated hopping in mixed valence phenomena

    Indian Academy of Sciences (India)

    N K Ghosh; S K Bhowmick; N S Mondal

    2011-01-01

    Role of correlated hopping is studied using extended Falicov–Kimball model in a small cluster. A discontinuous insulator-to-metal transition is observed at a critical -level energy. Transition is sharper for larger correlated hopping. In the specific heat curves a two-peak structure consisting of a sharp peak followed by a Schottky-type broad peak is exhibited. In a limited parameter region, some heavy-fermion like characteristics have been observed

  20. Low Power Multi-Hop Networking Analysis in Intelligent Environments.

    Science.gov (United States)

    Etxaniz, Josu; Aranguren, Gerardo

    2017-05-19

    Intelligent systems are driven by the latest technological advances in many different areas such as sensing, embedded systems, wireless communications or context recognition. This paper focuses on some of those areas. Concretely, the paper deals with wireless communications issues in embedded systems. More precisely, the paper combines the multi-hop networking with Bluetooth technology and a quality of service (QoS) metric, the latency. Bluetooth is a radio license-free worldwide communication standard that makes low power multi-hop wireless networking available. It establishes piconets (point-to-point and point-to-multipoint links) and scatternets (multi-hop networks). As a result, many Bluetooth nodes can be interconnected to set up ambient intelligent networks. Then, this paper presents the results of the investigation on multi-hop latency with park and sniff Bluetooth low power modes conducted over the hardware test bench previously implemented. In addition, the empirical models to estimate the latency of multi-hop communications over Bluetooth Asynchronous Connectionless Links (ACL) in park and sniff mode are given. The designers of devices and networks for intelligent systems will benefit from the estimation of the latency in Bluetooth multi-hop communications that the models provide.

  1. Comparison of whole-body vertical stiffness and leg stiffness during single-leg hopping in place in children and adults.

    Science.gov (United States)

    Beerse, Matthew; Wu, Jianhua

    2017-05-03

    In the hopping literature, whole-body vertical stiffness and leg stiffness are used interchangeably, due to most of the movement occurring in the vertical direction. However, there is some anterior/posterior movement of the center of mass and displacements of the foot during hopping in place in both children and adults. Further it is not understood if leg stiffness show a similar pattern as whole-body vertical stiffness when increasing hopping frequency. The purpose of this study was to test if whole-body vertical stiffness and leg stiffness are different during single-leg hopping in-place in children and adults, across a range of frequencies. Seventeen children aged 5-11years and 16 young adults participated in this study. The subjects hopped at their preferred frequency as well as 20% below, 20% above and 40% above preferred frequency. Our results demonstrate that both whole-body vertical stiffness and leg stiffness increase when increasing hopping frequency for children and adults. However, whole-body vertical stiffness consistently overestimates leg stiffness due to a similar peak force but a greater leg length change compared to vertical COM displacement. This suggests a considerable horizontal COM movement from landing to mid-stance during hopping. Children aged 5-11years old showed lower absolute values but higher normalized values of two stiffness measures than adults. This suggests somewhat adult-like stiffness control in children, but a reduced ability to manipulate the horizontal movement during single-leg hopping in place when compared to adults. Published by Elsevier Ltd.

  2. Hip Hop Syllabus: AME/MUS 303 Hip Hop: Art, Culture, and Politics

    Directory of Open Access Journals (Sweden)

    Sarah Hentges

    2013-10-01

    Full Text Available This syllabus represents a course taught online through the University of Maine at Augusta in the fall of 2011 (and every otheryear thereafter. Critical pedagogy can be a challenge in any classroom, and the challenges in an online classroom are compounded. However, the subject matter and approach of Hip Hop can be a powerful tool in teaching students critical thinking skills as well in laying a foundation for interdisciplinary and intersectional theory; here these elements are represented through curriculum—the themes, texts, contexts,approaches, structure, and assignments.

  3. Hopping conductivity in CaCu(2)O(3) single crystals.

    Science.gov (United States)

    Lisunov, K G; Arushanov, E; Raquet, B; Broto, J M; Chou, F C; Wizent, N; Behr, G

    2006-09-20

    The resistivity, ρ, of the spin-ladder compound CaCu(2)O(3) is investigated between T∼130-450 K. The ρ(T) data measured for [Formula: see text] (along the Cu-O-Cu leg) and [Formula: see text] (along the Cu-O-Cu rungs), ρ(a)(T)>ρ(b)(T), exhibit an activated dependence, similar in both directions and characterized by a nearest-neighbour hopping followed by a variable-range hopping (VRH) regime when T is decreased. A detailed analysis of ρ(T) demonstrates that conventional d-dimensional models of the hopping conductivity, based on the electron localization in disordered systems, cannot interpret the experimental data at any d = 1, 2 or 3, leading to the mismatch of the characteristic energies and/or unphysical values of the characteristic length scales. The observed VRH conductivity law on the low-temperature interval, lnρ∼T(-3/4), contradicts the models above, too. Instead, it is found that this law can be substantiated and the correct matching of the energy and length scales can be found within a model of Fogler et al (2004 Phys. Rev. B 69 035413) by treating CaCu(2)O(3) as a three-dimensional array of quasi-one-dimensional electron crystals.

  4. Hopping conductivity in CaCu{sub 2}O{sub 3} single crystals

    Energy Technology Data Exchange (ETDEWEB)

    Lisunov, K G [Institute of Applied Physics, Academy of Sciences of Moldova, Academiei Street 5, MD-2028 Kishinev (Moldova, Republic of); Arushanov, E [Institute of Applied Physics, Academy of Sciences of Moldova, Academiei Street 5, MD-2028 Kishinev (Moldova, Republic of); Raquet, B [Laboratoire National des Champs Magnetiques Pulses, 31432 Toulouse Cedex 04 (France); Broto, J M [Laboratoire National des Champs Magnetiques Pulses, 31432 Toulouse Cedex 04 (France); Chou, F C [Center for Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); Wizent, N [Leibniz Institute for Solid State and Materials Research, IFW Dresden, D-01171 Dresden (Germany); Behr, G [Leibniz Institute for Solid State and Materials Research, IFW Dresden, D-01171 Dresden (Germany)

    2006-09-20

    The resistivity, {rho}, of the spin-ladder compound CaCu{sub 2}O{sub 3} is investigated between T{approx}130-450 K. The {rho}(T) data measured for j parallel b (along the Cu-O-Cu leg) and j parallel a (along the Cu-O-Cu rungs), {rho}{sub a}(T)>{rho}{sub b}(T), exhibit an activated dependence, similar in both directions and characterized by a nearest-neighbour hopping followed by a variable-range hopping (VRH) regime when T is decreased. A detailed analysis of {rho}(T) demonstrates that conventional d-dimensional models of the hopping conductivity, based on the electron localization in disordered systems, cannot interpret the experimental data at any d = 1, 2 or 3, leading to the mismatch of the characteristic energies and/or unphysical values of the characteristic length scales. The observed VRH conductivity law on the low-temperature interval, ln{rho}{approx}T{sup -3/4}, contradicts the models above, too. Instead, it is found that this law can be substantiated and the correct matching of the energy and length scales can be found within a model of Fogler et al (2004 Phys. Rev. B 69 035413) by treating CaCu{sub 2}O{sub 3} as a three-dimensional array of quasi-one-dimensional electron crystals.

  5. Hopping conduction and random telegraph signal in an exfoliated multilayer MoS2 field-effect transistor

    Science.gov (United States)

    Li, Lijun; Lee, Inyeal; Youn, Doo-Hyeb; Kim, Gil-Ho

    2017-02-01

    We investigate the hopping conduction and random telegraph signal caused by various species of interface charge scatterers in a MoS2 multilayer field-effect transistor. The temperature dependence of the channel resistivity shows that at low temperatures and low carrier densities the carrier transport is via Mott variable range hopping with a hopping length changing from 41 to 80 nm. The hopping conduction was due to electron tunneling through localized band tail states formed by the scatterers located in the vicinity of the MoS2 layer. In the temperature range of 40-70 K, we observed random telegraph signal (RTS) that is caused by the capture and emission of a carrier by the interface traps that are located away from the layer. These traps form strong potential that interact with the layer and change the potential profile of the electron system. The characteristics of RTS depend strongly on gate bias and temperature, as well as the application of a magnetic field.

  6. Multilingual children's interaction with metafiction in a postmodern picture book

    DEFF Research Database (Denmark)

    Daugaard, Line Møller; Johansen, Martin Blok

    2014-01-01

    When teachers and school librarians choose picture books for multilingual children, they often base their choice on an evaluation of linguistic comprehensibility, content familiarity and cultural appropriateness. This means that postmodern picture books may be excluded. This paper presents a case...... study of multilingual children's encounter with a postmodern picture book with distinct metafictional features. In the page-by-page walkthroughs of the book, many of the multilingual children demonstrate a high level of literary competence. They deal with the book's metafictional features with great...... confidence and explicitly call for books which challenge them and break with their expectations as readers. Consequently, it is argued that postmodern picture books should be part of the range of books presented to multilingual children....

  7. Pinned vortex hopping in a neutron star crust

    CERN Document Server

    Haskell, Brynmor

    2015-01-01

    The motion of superfluid vortices in a neutron star crust is at the heart of most theories of pulsar glitches. Pinning of vortices to ions can decouple the superfluid from the crust and create a reservoir of angular momentum. Sudden large scale unpinning can lead to an observable glitch. In this paper we investigate the scattering of a free vortex off a pinning potential and calculate its mean free path, in order to assess whether unpinned vortices can skip multiple pinning sites and come close enough to their neighbours to trigger avalanches, or whether they simply hop from one pinning site to another giving rise to a more gradual creep. We find that there is a significant range of parameter space in which avalanches can be triggered, thus supporting the hypothesis that they may lie at the origin of pulsar glitches. For realistic values of the pinning force and superfluid drag parameters we find that avalanches are more likely in the higher density regions of the crust where pinning is stronger. Physical dif...

  8. A Picture of My Family

    Institute of Scientific and Technical Information of China (English)

    阳习周

    2008-01-01

    My name is Yang Xizhou.I’m a Chinese boy.I am thirteen.This isa picture of my family at home.It’s an old photo of my family.You cansee my father,my mother,my sister and I.We all look young because wetake①it five years ago.I was eight years old that year.

  9. Statistical Inference: The Big Picture.

    Science.gov (United States)

    Kass, Robert E

    2011-02-01

    Statistics has moved beyond the frequentist-Bayesian controversies of the past. Where does this leave our ability to interpret results? I suggest that a philosophy compatible with statistical practice, labelled here statistical pragmatism, serves as a foundation for inference. Statistical pragmatism is inclusive and emphasizes the assumptions that connect statistical models with observed data. I argue that introductory courses often mis-characterize the process of statistical inference and I propose an alternative "big picture" depiction.

  10. Teaching beginner ELLs using picture books tellability

    CERN Document Server

    Lado, Ana L (Luisa)

    2012-01-01

    Picture your beginning ELLs reading their way to success! For beginning ELLs, a picture really is worth a thousand words! Picture books are useful tools for building important language and social foundations that students may miss through traditional instruction. Ana Lado provides all the tools you'll need to engage ELLs of any age with picture books, including how to: Design lessons around picture books Select appropriate titles using specific criteria Incorporate fun and engaging strategies like singing and reenacting Access the book's searchable online database to find the right book Integrate picture-book learning to facilitate development of English Language Proficiency.

  11. From "They" Science to "Our" Science: Hip Hop Epistemology in STEAM Education

    Science.gov (United States)

    Dolberry, Maurice E.

    Hip hop has moved from being considered a type of music into being understood as a culture in which a prominent type of music originates. Hip hop culture has a philosophy and epistemological constructs as well. This study analyzed those constructs to determine how conceptions of science factor in hip hop worldviews. Pedagogical models in culturally responsive teaching and Science, Technology, Engineering, Arts, and Mathematics (STEAM) education were also examined to discern their philosophical connections with hip hop culture. These connections were used to create two theoretical models. The first one, Hip Hop Science, described how scientific thought functions in hip hop culture. The second model, Hip Hop STEAM Pedagogy, proposes how hip hop culture can inform STEAM teaching practices. The study began by using Critical Race Theory to create a theoretical framework proposing how the two theoretical models could be derived from the philosophical and pedagogical concepts. Content analysis and narrative inquiry were used to analyze data collected from scholarly texts, hip hop songs, and interviews with hip hop-responsive educators. The data from these sources were used initially to assess the adequacy of the proposed theoretical framework, and subsequently to improve its viability. Four overlapping themes emerged from the data analyses, including hip hop-resistance to formal education; how hip hop culture informs pedagogical practice in hip hop-responsive classrooms; conceptions of knowledge and reality that shape how hip hoppers conduct scientific inquiry; and hip hop-based philosophies of effective teaching for hip hoppers as a marginalized cultural group. The findings indicate that there are unique connections between hip hop epistemology, sciencemindedness, and pedagogical practices in STEAM education. The revised theoretical framework clarified the nature of these connections, and supported claims from prior research that hip hop culture provides viable sites of

  12. Mic Power? Connections and the hip hop nation in Kampala, Uganda

    DEFF Research Database (Denmark)

    Schneidermann, Nanna

    2014-01-01

    Hip hop culture has been celebrated in the media and scholarship as a universal youth language, part of a global hip hop nation, and a type of counter-public. This article examines the everyday meanings and practices of hip hop among hip hop activists in Kampala, Uganda, specifically within...... the Batuuze rap group. Rather than portraying hip hop as a counter-public of the disempowered, I argue that the Batuuze engagement is based on what I call moral economy that enables the negotiation of connections in social and cultural networks towards what is considered a good life. Here, the hip hop nation...

  13. Hip Hop Dance Experience Linked to Sociocognitive Ability.

    Science.gov (United States)

    Bonny, Justin W; Lindberg, Jenna C; Pacampara, Marc C

    2017-01-01

    Expertise within gaming (e.g., chess, video games) and kinesthetic (e.g., sports, classical dance) activities has been found to be linked with specific cognitive skills. Some of these skills, working memory, mental rotation, problem solving, are linked to higher performance in science, technology, math, and engineering (STEM) disciplines. In the present study, we examined whether experience in a different activity, hip hop dance, is also linked to cognitive abilities connected with STEM skills as well as social cognition ability. Dancers who varied in hip hop and other dance style experience were presented with a set of computerized tasks that assessed working memory capacity, mental rotation speed, problem solving efficiency, and theory of mind. We found that, when controlling for demographic factors and other dance style experience, those with greater hip hop dance experience were faster at mentally rotating images of hands at greater angle disparities and there was a trend for greater accuracy at identifying positive emotions displayed by cropped images of human faces. We suggest that hip hop dance, similar to other more technical activities such as video gameplay, tap some specific cognitive abilities that underlie STEM skills. Furthermore, we suggest that hip hop dance experience can be used to reach populations who may not otherwise be interested in other kinesthetic or gaming activities and potentially enhance select sociocognitive skills.

  14. Hip Hop Dance Experience Linked to Sociocognitive Ability

    Science.gov (United States)

    Bonny, Justin W.; Lindberg, Jenna C.; Pacampara, Marc C.

    2017-01-01

    Expertise within gaming (e.g., chess, video games) and kinesthetic (e.g., sports, classical dance) activities has been found to be linked with specific cognitive skills. Some of these skills, working memory, mental rotation, problem solving, are linked to higher performance in science, technology, math, and engineering (STEM) disciplines. In the present study, we examined whether experience in a different activity, hip hop dance, is also linked to cognitive abilities connected with STEM skills as well as social cognition ability. Dancers who varied in hip hop and other dance style experience were presented with a set of computerized tasks that assessed working memory capacity, mental rotation speed, problem solving efficiency, and theory of mind. We found that, when controlling for demographic factors and other dance style experience, those with greater hip hop dance experience were faster at mentally rotating images of hands at greater angle disparities and there was a trend for greater accuracy at identifying positive emotions displayed by cropped images of human faces. We suggest that hip hop dance, similar to other more technical activities such as video gameplay, tap some specific cognitive abilities that underlie STEM skills. Furthermore, we suggest that hip hop dance experience can be used to reach populations who may not otherwise be interested in other kinesthetic or gaming activities and potentially enhance select sociocognitive skills. PMID:28146562

  15. A Picture of Subsidized Households 2009

    Data.gov (United States)

    Department of Housing and Urban Development — Picture of Subsidized Households describes the nearly 5 million households living in HUD-subsidized housing in the United States for the year 2009. Picture 2009...

  16. A Picture of Subsidized Housholds 2008

    Data.gov (United States)

    Department of Housing and Urban Development — Picture of Subsidized Households describes the nearly 5 million households living in HUD-subsidized housing in the United States for the year 2008. Picture 2008...

  17. Removal Of Contaminants From Aqueous Solutions Using Hop (Humulus Lupulus L. Agricultural By-Products

    Directory of Open Access Journals (Sweden)

    Partelová Denisa

    2015-12-01

    Full Text Available Agricultural wastes can be used as an alternative to the existing sorbents for the removal of metals or synthetic dyes from contaminated liquids. In this work, the fine powdered biomass of the hop (Humulus lupulus L. variety Osvald's clone 72 and variety Bohemie as a sorbent for the removal of Cd from aqueous solutions of CdCl2 spiked with radionuclide 109Cd and synthetic dyes thioflavine T (ThT or methylene blue (MB from single dye solutions under conditions of batch systems was used. The maximum sorption capacity Q = 264 µmol Cd/g (d.w. was found in the case of the leaf biomass of hop (H. lupulus L. variety Osvald's clone 72 at the initial concentration of CdCl2 10,000 µmol/dm3, whereby the sorption capacity decreased in the order Qleaves : Qstems : Qroots = 1.0 : 0.8 : 0.7. The sorbed amount of Cd was removed from the hop biomass with the following increasing desorption efficiency of the extraction reagents: deionised H2O << 0.1 mol/dm3 HCl ≤ 0.1 mol/dm3 EDTA-Na2. Similarly as in the case of Cd sorption, the kinetics of ThT and MB sorption by the leaf biomass of the hop (H. lupulus L. variety Bohemie were also showed as two-phase processes. The maximum sorption of ThT approx. Q = 19 mg/g (d.w. and MB approx. Q = 70 mg/g (d.w. were found within the range of the initial values of pH 4 – 7. The sorption of both dyes by the leaf biomass from single dye solutions decreased with increasing biomass concentration and on the other hand increased with increasing the initial concentrations of ThT or MB. The process of ThT and MB sorption was better described by the Langmuir model than the Freundlich model of sorption isotherm. From the obtained values of Qmax, it was found that in the case of MB the dried leaf biomass showed more than 2-times higher sorption capacity (Qmax = 184 mg/g; d.w. in comparison with the value predicted for ThT. Obtained results suggest that dried plant biomass of hop (H. lupulus L. as agricultural by-products can be used

  18. Text-Picture Relations in Cooking Instructions

    NARCIS (Netherlands)

    van der Sluis, Ielka; Leito, Shadira; Redeker, Gisela; Bunt, Harry

    2016-01-01

    Like many other instructions, recipes on packages with ready-to-use ingredients for a dish combine a series of pictures with short text paragraphs. The information presentation in such multimodal instructions can be compact (either text or picture) and/or cohesive (text and picture). In an explorato

  19. 32 CFR 705.8 - Motion pictures.

    Science.gov (United States)

    2010-07-01

    ... 32 National Defense 5 2010-07-01 2010-07-01 false Motion pictures. 705.8 Section 705.8 National... OFFICIAL RECORDS PUBLIC AFFAIRS REGULATIONS § 705.8 Motion pictures. (a) The rules and procedures given in the preceding for TV will also apply to cooperation with commercial motion picture producers. (b)...

  20. On the Effective Capacity of Two-Hop Communication Systems

    CERN Document Server

    Qiao, Deli; Velipasalar, Senem

    2010-01-01

    In this paper, two-hop communication between a source and a destination with the aid of an intermediate relay node is considered. Both the source and intermediate relay node are assumed to operate under statistical quality of service (QoS) constraints imposed as limitations on the buffer overflow probabilities. It is further assumed that the nodes send the information at fixed power levels and have perfect channel side information. In this scenario, the maximum constant arrival rates that can be supported by this two-hop link are characterized by finding the effective capacity. Through this analysis, the impact upon the throughput of having buffer constraints at the source and intermediate-hop nodes is identified.

  1. Surface hopping in laser-driven molecular dynamics

    Science.gov (United States)

    Fiedlschuster, T.; Handt, J.; Gross, E. K. U.; Schmidt, R.

    2017-06-01

    A theoretical justification of the empirical surface hopping method for the laser-driven molecular dynamics is given by utilizing the formalism of the exact factorization of the molecular wave function [Abedi et al., Phys. Rev. Lett. 105, 123002 (2010), 10.1103/PhysRevLett.105.123002] in its quantum-classical limit. Employing an exactly solvable H2+-like model system, it is shown that the deterministic classical nuclear motion on a single time-dependent surface in this approach describes the same physics as stochastic (hopping-induced) motion on several surfaces, provided Floquet surfaces are applied. Both quantum-classical methods do describe reasonably well the exact nuclear wave-packet dynamics for extremely different dissociation scenarios. Hopping schemes using Born-Oppenheimer surfaces or instantaneous Born-Oppenheimer surfaces fail completely.

  2. Surface hopping methodology in laser-driven molecular dynamics

    CERN Document Server

    Fiedlschuster, T; Gross, E K U; Schmidt, R

    2016-01-01

    A theoretical justification of the empirical surface hopping method for the laser-driven molecular dynamics is given utilizing the formalism of the exact factorization of the molecular wavefunction [Abedi et al., PRL $\\textbf{105}$, 123002 (2010)] in its quantum-classical limit. Employing an exactly solvable $\\textrm H_2^{\\;+}$-like model system, it is shown that the deterministic classical nuclear motion on a single time-dependent surface in this approach describes the same physics as stochastic (hopping-induced) motion on several surfaces, provided Floquet surfaces are applied. Both quantum-classical methods do describe reasonably well the exact nuclear wavepacket dynamics for extremely different dissociation scenarios. Hopping schemes using Born-Oppenheimer surfaces or instantaneous Born-Oppenheimer surfaces fail completely.

  3. Switched diversity strategies for dual-hop relaying systems

    KAUST Repository

    Gaaloul, Fakhreddine

    2011-04-29

    This paper investigates the effect of different switched diversity configurations on the implementation complexity and achieved performance of dual-hop amplify-and-forward (AF) relaying networks. A low-complexity model of the relay station is adopted, wherein single-input single-output antenna configuration is employed. Each of the transmitter and the receiver however employs multiple antennas to improve the overall link performance. Single-phase and two-phase based receive switching strategies are investigated assuming optimum first hop signal-to-noise ratio (SNR). Moreover, the simple scheme in which the switched diversity is applied independently over the two hops is studied using tight upper bounds. Thorough performance comparisons and switching thresholds optimization for the aforementioned strategies are presented. Simulation results are also provided to validate the mathematical development and to verify the numerical computations.

  4. RADAR HRR PROFILING FOR GROUND MOVING TARGET USING PHASE-CODED AND HOPPED-FREQUENCY WAVEFORMS

    Institute of Scientific and Technical Information of China (English)

    Li Yan; Wang Changming

    2007-01-01

    To obtain the radar High Range Resolution (HRR) profile of the slowly moving ground target in strong clutter background, the Phase-Coded Hopped-Frequency (PCHF) waveform is proposed. By multiple-bursts coherent processing, the HRR profile synthesis, target velocity compensation and clutter compression can be accomplished simultaneously. The new waveform is shown to have good ability to suppress ground clutter and good Electronic Counter-CounterMeasures (ECCM) ability as well. The clutter compression performance of the proposed method is verified by the numerical results.

  5. Multicollinearity-based 3D DV-Hop Localization Algorithm%一种基于多重共线性的三维DV-Hop定位算法

    Institute of Scientific and Technical Information of China (English)

    严筱永; 钱焕延; 高德民; 于继明

    2011-01-01

    To overcome the disadvantage of multilateral ranging method, consider the location algorithm applied realistic environment,based on the characteristics of DV-Hop, an improved three-dimensional localization algorithm was proposed. The algorithm not only transplants DV-Hop localization algorithm from two dimensions to three-dimensional space outside,also taking into account the algorithm beacon node topology and hops on the localization accuracy, and a Multicollinearity-Based 3D DV-Hop Algorithm(MCB3D DV-Hop) was proposed. The algorithm sets two threshold parameters of hop and multicollinearity,and selects the good beacon node teams to realizethe position estimate. Theoretical analysis and simulations results show that our proposed method works well.%针对多边测距法的不足,考虑定位算法所应用的现实环境,在典型DV-Hop算法的基础上,提出了一种改进的三维定位算法.该算法除了将DV-Hop定位算法从二维空间移植到三维空间以外,着重考虑了信标节点拓扑关系和跳数对定位精度的影响,提出一种基于多重共线性的三维DV-Hop定位算法MCB3D DV-Hop.该算法通过设置跳数阈值与多重共线性阅值两个阈值参数,挑选网络中好的信标节点组进行位置估计.理论分析和仿真实验结果表明了算法有较高的定位精度和稳定性.

  6. Liquid Crystal Motion Picture Projector①

    Institute of Scientific and Technical Information of China (English)

    SHIYongji

    1997-01-01

    A liquid crystal moving picture projector and method are described.Light incident on a liquid crystal display-type device is selectively scattered or transmitted by respective portions of liquid crystal display,and a projection mechanism projects an image formed by either such scattered light or such transmitted light.A liquid cystal moving picture projector includes a liquid crystal display for creating characteristics of an image,and projecttion optics for projecting images sequentially created by the display.The display includes a liquid crystal material capable of temporary storing information at respective areas.The temporary storage may be a function of charge storing directly on liquid crystal material.A method of projecting plural images in sequence includes:creating an image or characteristics of an image in a liquid crystal material,storing such image in such liquid crystal material,directing light at such liquid crystal material,projecting such image as a function of light transmitted through or scattered by such liquid crystal material,and creating a further image in such liquid crystal material for subsequent projection.

  7. New Iterated Decoding Algorithm Based on Differential Frequency Hopping System

    Institute of Scientific and Technical Information of China (English)

    LIANG Fu-lin; LUO Wei-xiong

    2005-01-01

    A new iterated decoding algorithm is proposed for differential frequency hopping (DFH) encoder concatenated with multi-frequency shift-key (MFSK) modulator. According to the character of the frequency hopping (FH) pattern trellis produced by DFH function, maximum a posteriori (MAP) probability theory is applied to realize the iterate decoding of it. Further, the initial conditions for the new iterate algorithm based on MAP algorithm are modified for better performance. Finally, the simulation result compared with that from traditional algorithms shows good anti-interference performance.

  8. RESEARCH ON JUMPING SEQUENCE PLANNING ISSUES OF HOPPING ROBOTS

    Institute of Scientific and Technical Information of China (English)

    LIUZhuang-zhi; ZHUJian-ying

    2004-01-01

    The wheeled or crawled robots often suffer from big obstacles or ditches, so a hopping robot needs to fit the tough landform in the field environments. In order to jump over obstacles rapidly, a jumping sequence must be generated based on the landform information from sensors or user input. The planning method for planar mobile robots is compared with that of hopping robots. Several factors can change the planning result. Adjusting these coefficients, a heuristic searching algorithm for the jumping sequence is developed on a simplified landform. Calculational result indicates that the algorithm can achieve safety and efficient control sequences for a desired goal.

  9. Construction of Frequency Hopping Sequence Set Based upon Generalized Cyclotomy

    CERN Document Server

    Liu, Fang; Zhou, Zhengchun; Tang, Xiaohu

    2010-01-01

    Frequency hopping (FH) sequences play a key role in frequency hopping spread spectrum communication systems. It is important to find FH sequences which have simultaneously good Hamming correlation, large family size and large period. In this paper, a new set of FH sequences with large period is proposed, and the Hamming correlation distribution of the new set is investigated. The construction of new FH sequences is based upon Whiteman's generalized cyclotomy. It is shown that the proposed FH sequence set is optimal with respect to the average Hamming correlation bound.

  10. Optimal Transmission Policies for Energy Harvesting Two-hop Networks

    CERN Document Server

    Orhan, Oner

    2012-01-01

    In this paper, a two-hop communication system with energy harvesting nodes is considered. Unlike battery powered wireless nodes, both the source and the relay are able to harvest energy from environment during communication, therefore, both data and energy causality over the two hops need to be considered. Assuming both nodes know the harvested energies in advance, properties of optimal transmission policies to maximize the delivered data by a given deadline are identified. Using these properties, optimal power allocation and transmission schedule for the case in which both nodes harvest two energy packets is developed.

  11. Linear Span of the Optimal Frequency Hopping Sequences from Irreducible Cyclic Co des

    Institute of Scientific and Technical Information of China (English)

    GAO Juntao; HU Yupu; LI Xuelian

    2015-01-01

    Optimal set of the frequency hopping se-quences can be derived from some irreducible cyclic codes. This paper determines the linear span of the frequency hopping sequences in the optimal set. The linear span is much less than the length of the frequency hopping se-quences. In order to improve the linear span, we use two types of permutation polynomials, power permutation and binomial permutation, to transform the optimal set of the frequency hopping sequences. The transformed frequency hopping sequences have optimal Hamming correlation and larger linear span than the original frequency hopping se-quences. Compared with the original frequency hopping sequences, the transformed optimal frequency hopping se-quences have higher security to resist the cryptanalytic method.

  12. Suppression of Plant Immune Responses by the Pseudomonas savastanoi pv. savastanoi NCPPB 3335 Type III Effector Tyrosine Phosphatases HopAO1 and HopAO2

    Science.gov (United States)

    Castañeda-Ojeda, María Pilar; Moreno-Pérez, Alba; Ramos, Cayo; López-Solanilla, Emilia

    2017-01-01

    The effector repertoire of the olive pathogen P. savastanoi pv. savastanoi NCPPB 3335 includes two members of the HopAO effector family, one of the most diverse T3E families of the P. syringae complex. The study described here explores the phylogeny of these dissimilar members, HopAO1 and HopAO2, among the complex and reveals their activities as immune defense suppressors. Although HopAO1 is predominantly encoded by phylogroup 3 strains isolated from woody organs of woody hosts, both HopAO1 and HopAO2 are phylogenetically clustered according to the woody/herbaceous nature of their host of isolation, suggesting host specialization of the HopAO family across the P. syringae complex. HopAO1 and HopAO2 translocate into plant cells and show hrpL-dependent expression, which allows their classification as actively deployed type III effectors. Our data also show that HopAO1 and HopAO2 possess phosphatase activity, a hallmark of the members of this family. Both of them exert an inhibitory effect on early plant defense responses, such as ROS production and callose deposition, and are able to suppress ETI responses induced by the effectorless polymutant of P. syringae pv. tomato DC3000 (DC3000D28E) in Nicotiana. Moreover, we demonstrate that a ΔhopAO1 mutant of P. savastanoi NCPBB 3335 exhibits a reduced fitness and virulence in olive plants, which supports the relevance of this effector during the interaction of this strain with its host plants. This work contributes to the field with the first report regarding functional analysis of HopAO homologs encoded by P. syringae or P. savastanoi strains isolated from woody hosts. PMID:28529516

  13. Suppression of Plant Immune Responses by the Pseudomonas savastanoi pv. savastanoi NCPPB 3335 Type III Effector Tyrosine Phosphatases HopAO1 and HopAO2

    Directory of Open Access Journals (Sweden)

    María Pilar Castañeda-Ojeda

    2017-05-01

    Full Text Available The effector repertoire of the olive pathogen P. savastanoi pv. savastanoi NCPPB 3335 includes two members of the HopAO effector family, one of the most diverse T3E families of the P. syringae complex. The study described here explores the phylogeny of these dissimilar members, HopAO1 and HopAO2, among the complex and reveals their activities as immune defense suppressors. Although HopAO1 is predominantly encoded by phylogroup 3 strains isolated from woody organs of woody hosts, both HopAO1 and HopAO2 are phylogenetically clustered according to the woody/herbaceous nature of their host of isolation, suggesting host specialization of the HopAO family across the P. syringae complex. HopAO1 and HopAO2 translocate into plant cells and show hrpL-dependent expression, which allows their classification as actively deployed type III effectors. Our data also show that HopAO1 and HopAO2 possess phosphatase activity, a hallmark of the members of this family. Both of them exert an inhibitory effect on early plant defense responses, such as ROS production and callose deposition, and are able to suppress ETI responses induced by the effectorless polymutant of P. syringae pv. tomato DC3000 (DC3000D28E in Nicotiana. Moreover, we demonstrate that a ΔhopAO1 mutant of P. savastanoi NCPBB 3335 exhibits a reduced fitness and virulence in olive plants, which supports the relevance of this effector during the interaction of this strain with its host plants. This work contributes to the field with the first report regarding functional analysis of HopAO homologs encoded by P. syringae or P. savastanoi strains isolated from woody hosts.

  14. Post-Menopausal Vaginal Hemorrhage Related to the Use of a Hop-Containing Phytotherapeutic Product

    NARCIS (Netherlands)

    van Hunsel, Florence; van de Koppel, Sonja; van Puijenbroek, Eugène

    2015-01-01

    Two 54-year-old women developed abdominal cramps and vaginal hemorrhage as a result of endometrial hyperplasia during treatment with a hop-containing phytotherapeutic product (MenoCool®) for post-menopausal complaints. The women used the hop-containing phytotherapeutic product (418 mg of hop per tab

  15. Flipping the Misogynist Script: Gender, Agency, Hip Hop and Music Education

    Science.gov (United States)

    Tobias, Evan S.

    2014-01-01

    Excluding Hip Hop culture and rap music from music education misses opportunities for addressing key aspects of popular culture, society, and students' lives. This article addresses intersections of Hip Hop, gender, and music education to forward potential Hip Hop praxis. After tracing related scholarship, I discuss and problematize…

  16. Flipping the Misogynist Script: Gender, Agency, Hip Hop and Music Education

    Science.gov (United States)

    Tobias, Evan S.

    2014-01-01

    Excluding Hip Hop culture and rap music from music education misses opportunities for addressing key aspects of popular culture, society, and students' lives. This article addresses intersections of Hip Hop, gender, and music education to forward potential Hip Hop praxis. After tracing related scholarship, I discuss and problematize…

  17. Wish to Live: The Hip-Hop Feminism Pedagogy Reader. Educational Psychology. Volume 3

    Science.gov (United States)

    Brown, Ruth Nicole, Ed.; Kwakye, Chamara Jewel, Ed.

    2012-01-01

    "Wish To Live: The Hip-hop Feminism Pedagogy Reader" moves beyond the traditional understanding of the four elements of hip-hop culture--rapping, breakdancing, graffiti art, and deejaying--to articulate how hip-hop feminist scholarship can inform educational practices and spark, transform, encourage, and sustain local and global youth…

  18. Post-Menopausal Vaginal Hemorrhage Related to the Use of a Hop-Containing Phytotherapeutic Product

    NARCIS (Netherlands)

    van Hunsel, Florence; van de Koppel, Sonja; van Puijenbroek, Eugène

    2015-01-01

    Two 54-year-old women developed abdominal cramps and vaginal hemorrhage as a result of endometrial hyperplasia during treatment with a hop-containing phytotherapeutic product (MenoCool®) for post-menopausal complaints. The women used the hop-containing phytotherapeutic product (418 mg of hop per

  19. From phase separation to long-range order in a system of interacting electrons

    Science.gov (United States)

    Derzhko, Volodymyr; Jȩdrzejewski, Janusz

    2003-10-01

    We study a system composed of fermions (electrons), hopping on a square lattice, and of immobile particles (ions), that is described by the spinless Falicov-Kimball Hamiltonian augmented by a next-nearest-neighbor attractive interaction between the ions (a nearest-neighbor repulsive interaction between the ions can be included and does not alter the results). A part of the grand-canonical phase diagram of this system is constructed rigorously, when the coupling between the electrons and ions is much stronger than the hopping intensity of electrons. The obtained diagram implies that, at least for a few rational densities of particles, by increasing the hopping intensity the system can be driven from a state of phase separation to a state with a long-range order. This kind of transitions occurs also, when the hopping fermions are replaced by hopping hard-core bosons.

  20. The effect of correlations on the non-ohmic behavior of the small-polaron hopping conductivity in 1D and 3D disordered systems

    Energy Technology Data Exchange (ETDEWEB)

    Dimakogianni, M; Triberis, G P, E-mail: gtriber@phys.uoa.g [Solid State Section, Physics Department, University of Athens, Panepistimiopolis, GR-15784 Zografos, Athens (Greece)

    2010-09-08

    According to percolation theory the investigation of charge transport in disordered systems is equivalent to the study of the possibility of the passage of the carriers through a random network of impedances which interconnect the different lattice sites. When the site energies are not the same, the energy of a site affects the incoming as well as the outgoing impedances connected to the given site and this gives rise to correlations between neighboring impedances. This new condition characterizes the transport process and imposes the evaluation of the average number of sites accessible by a bond from a given site for all possible configurations of sites that satisfy the percolation condition. The generalized molecular crystal model, appropriate for the study of small-polaron hopping transport in disordered systems, and the Kubo formula permit the evaluation of these impedances. Taking correlations into account, theoretical percolation considerations applicable to one-dimensional and three-dimensional disordered systems, lead to analytical expressions for the temperature and electric field dependence of the DC conductivity at high (multi-phonon-assisted hopping) and low (few-phonon-assisted hopping) temperatures. The theoretical analysis reveals the effect of correlations on the non-ohmic behavior of the small-polaron hopping conductivity and permits the evaluation of the maximum hopping distance. Quantitative estimates of this effect are presented comparing the theoretical results, including correlations with those ignoring them, previously reported, applying them to recent experimental data for a wide temperature range and from low up to moderate electric fields.

  1. Validation of the Amsterdam Beverage Picture Set: A Controlled Picture Set for Cognitive Bias Measurement and Modification Paradigms.

    Science.gov (United States)

    Pronk, Thomas; van Deursen, Denise S; Beraha, Esther M; Larsen, Helle; Wiers, Reinout W

    2015-10-01

    Alcohol research may benefit from controlled and validated picture sets. We have constructed the Amsterdam Beverage Picture Set (ABPS), which was designed for alcohol research in general and cognitive bias measurement and modification in particular. Here, we first formulate a position on alcohol stimulus validity that prescribes that alcohol-containing pictures, compared to nonalcohol-containing pictures, should induce a stronger urge to drink in heavy drinkers than in light drinkers. Because a perceptually simple picture might induce stronger cognitive biases but the presence of a drinking context might induce a stronger urge to drink, the ABPS contains pictures with and without drinking context. By limiting drinking contexts to simple consumption scenes instead of real-life scenes, complexity was minimized. A validation study was conducted to establish validity, to examine ABPS drinking contexts, and to explore the role of familiarity, valence, arousal, and control. Two hundred ninety-one psychology students completed the Alcohol Use Disorders Identification Test, as well as rating and recognition tasks for a subset of the ABPS pictures. The ABPS was well-recognized, familiar, and heavy drinkers reported a greater urge to drink in response to the alcohol-containing pictures only. Alcohol presented in drinking context did not elicit a stronger urge to drink but was recognized more slowly than alcohol presented without context. The ABPS was found to be valid, although pictures without context might be preferable for measuring cognitive biases than pictures with context. We discuss how an explicit approach to picture construction may aid in creating variations of the ABPS. Finally, we describe how ABPS adoption across studies may allow more reproducible and comparable results across paradigms, while allowing researchers to apply picture selection criteria that correspond to a wide range of theoretical positions. The latter is exemplified by ABPS derivatives and

  2. Multiple-hopping trajectories near a rotating asteroid

    Science.gov (United States)

    Shen, Hong-Xin; Zhang, Tian-Jiao; Li, Zhao; Li, Heng-Nian

    2017-03-01

    We present a study of the transfer orbits connecting landing points of irregular-shaped asteroids. The landing points do not touch the surface of the asteroids and are chosen several meters above the surface. The ant colony optimization technique is used to calculate the multiple-hopping trajectories near an arbitrary irregular asteroid. This new method has three steps which are as follows: (1) the search of the maximal clique of candidate target landing points; (2) leg optimization connecting all landing point pairs; and (3) the hopping sequence optimization. In particular this method is applied to asteroids 433 Eros and 216 Kleopatra. We impose a critical constraint on the target landing points to allow for extensive exploration of the asteroid: the relative distance between all the arrived target positions should be larger than a minimum allowed value. Ant colony optimization is applied to find the set and sequence of targets, and the differential evolution algorithm is used to solve for the hopping orbits. The minimum-velocity increment tours of hopping trajectories connecting all the landing positions are obtained by ant colony optimization. The results from different size asteroids indicate that the cost of the minimum velocity-increment tour depends on the size of the asteroids.

  3. Contribution of afferent feedback and descending drive to human hopping

    DEFF Research Database (Denmark)

    Zuur, Abraham T.; Lundbye-Jensen, Jesper; Leukel, Christian

    2010-01-01

    to inhibit the motor cortex and this resulted in a suppression of the early EMG burst. These results suggest that sensory feedback and descending drive from the motor cortex are integrated to drive the motor neuron pool during the early EMG burst in hopping. Thus, simple reflexes work in concert with higher...

  4. Adaptive Resource Control in 2-hop Ad-Hoc Networks

    NARCIS (Netherlands)

    Yang, Y.; Heijenk, Gerhard J.; Haverkort, Boudewijn R.H.M.

    2009-01-01

    This paper presents a simple resource control mechanism with traffic scheduling for 2-hop ad-hoc networks, in which the Request-To-Send (RTS) packet is utilized to deliver feedback information. With this feedback information, the Transmission Opportunity (TXOP) limit of the sources can be controlled

  5. Young Children Manifest Spiritualities in Their Hip-Hop Writing

    Science.gov (United States)

    Norton, Nadjwa E. L.

    2014-01-01

    In this article, the author combines multicultural feminist critical theories with the voices of Black and Latina/Latino young spiritual children to extend culturally responsive teaching. The author illuminates how children use their hip-hop writing to construct themselves as people who communicate with God, choose spiritual content for their…

  6. Maroc-hop: music and youth identities in the Netherlands

    NARCIS (Netherlands)

    Gazzah, M.; Herrera, L.; Bayat, A.

    2010-01-01

    Two musical forms highly popular among youths of Moroccan origin in the Netherlands—Maroc-hop and Shaabi—permit youths to express specific and multiple identities in local contexts. Shaabi, a popular form of Moroccan folk music used to be found mainly in the private setting of family celebrations, m

  7. Hopping in a supercooled binary Lennard-Jones liquid

    DEFF Research Database (Denmark)

    Schrøder, Thomas; Dyre, Jeppe

    1998-01-01

    A binary Lennard–Jones liquid has been investigated by molecular dynamics at equilibrium supercooled conditions. At the lowest temperature investigated, hopping is present in the system as indicated by a secondary peak in 4r2Gs(r,t), where Gs(r,t) is the van Hove self correlation function...

  8. Investigación a ritmo de hip-hop

    Directory of Open Access Journals (Sweden)

    Melisa Rivière

    2013-09-01

    Full Text Available Soñando se resiste. Hip-hop; en la calle y al parque. Varios autores. Alcaldía Mayor de Bogotá, Secretaría de Cultura, Recreación y Deporte, Orquesta Filarmónica de Bogotá, Bogotá, 2010, 180 págs.

  9. Hop pellets as an interesting source of antioxidant active compounds

    Directory of Open Access Journals (Sweden)

    Andrea Holubková

    2013-02-01

    Full Text Available Hop is a plant used by humankind for thousands of years. This plant is one of the main and indispensable raw materials for the beer production. It is used for various dishes preparation in the cuisine. Hop is also used to inhibit bacterial contamination. The hop extracts are used for its sedative, antiseptic and antioxidant properties in medicine, as a part of many phytopharmaceuticals. The present paper have focused on the extraction of polyphenolic compounds from 4 samples of hop pellets varieties of Aurora, Saaz, Lublin and Saphir, on the analyzing of bioactive substances (polyphenolics and flavonoids in prepared extracts and on the determination of antioxidant activity.  The highest content of polyphenolic substances was determined in the sample Lublin (153.06 mg gallic acid (GAE/g and Saaz (151.87 mg GAE/g. The amount of flavonoids in the samples  was descending order Saaz > Saphir > Aurora > Lublin. Hops, as plant, is known by high content of antioxidant active substances. Antioxidant activity was determined using three independent spectrofotometric methods, radical scavenging assays using 2,2′-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS and 1,1-diphenyl-2-picrylhydrazyl (DPPH radical and ferric reducing antioxidant power (FRAP. The sample Aurora showed the highest ability to scavenge of ABTS radical cation. Antioxidant activity continued to decline in a row Saphir> Lublin> Saaz. The same trend was also observed by using the FRAP assay. The most effective DPPH radical scavengering activity had the sample Saaz a Saphir (p>0.05.doi:10.5219/270 Normal 0 21 false false false SK X-NONE X-NONE

  10. Charge Carrier Hopping Dynamics in Homogeneously Broadened PbS Quantum Dot Solids.

    Science.gov (United States)

    Gilmore, Rachel H; Lee, Elizabeth M Y; Weidman, Mark C; Willard, Adam P; Tisdale, William A

    2017-02-08

    Energetic disorder in quantum dot solids adversely impacts charge carrier transport in quantum dot solar cells and electronic devices. Here, we use ultrafast transient absorption spectroscopy to show that homogeneously broadened PbS quantum dot arrays (σhom(2):σinh(2) > 19:1, σinh/kBT quantum dot batches are sufficiently monodisperse (δ ≲ 3.3%). The homogeneous line width is found to be an inverse function of quantum dot size, monotonically increasing from ∼25 meV for the largest quantum dots (5.8 nm diameter/0.92 eV energy) to ∼55 meV for the smallest (4.1 nm/1.3 eV energy). Furthermore, we show that intrinsic charge carrier hopping rates are faster for smaller quantum dots. This finding is the opposite of the mobility trend commonly observed in device measurements but is consistent with theoretical predictions. Fitting our data to a kinetic Monte Carlo model, we extract charge carrier hopping times ranging from 80 ps for the smallest quantum dots to over 1 ns for the largest, with the same ethanethiol ligand treatment. Additionally, we make the surprising observation that, in slightly polydisperse (δ ≲ 4%) quantum dot solids, structural disorder has a greater impact than energetic disorder in inhibiting charge carrier transport. These findings emphasize how small improvements in batch size dispersity can have a dramatic impact on intrinsic charge carrier hopping behavior and will stimulate further improvements in quantum dot device performance.

  11. Communication: Proper treatment of classically forbidden electronic transitions significantly improves detailed balance in surface hopping.

    Science.gov (United States)

    Sifain, Andrew E; Wang, Linjun; Prezhdo, Oleg V

    2016-06-01

    Surface hopping is the most popular method for nonadiabatic molecular dynamics. Many have reported that it does not rigorously attain detailed balance at thermal equilibrium, but does so approximately. We show that convergence to the Boltzmann populations is significantly improved when the nuclear velocity is reversed after a classically forbidden hop. The proposed prescription significantly reduces the total number of classically forbidden hops encountered along a trajectory, suggesting that some randomization in nuclear velocity is needed when classically forbidden hops constitute a large fraction of attempted hops. Our results are verified computationally using two- and three-level quantum subsystems, coupled to a classical bath undergoing Langevin dynamics.

  12. The influence of f-electron hopping on ground states and valence transitions in the extended Falicov-Kimball model

    Science.gov (United States)

    Farkašovský, Pavol; Čenčariková, Hana

    2014-09-01

    The ground-state phase diagram of the extended Falicov-Kimball model with f- f electron hopping is studied numerically in the one-dimensional case. To identify the nature of ground states three complementary numerical methods are used, and namely, (i) the small-cluster exact-diagonalization method, (ii) the density-matrix-renormalization-group method (DMRG) and (iii) an approximate, but very accurate, numerical method based on the reduction of the Hilbert space. It is found that the physics of the Falicov-Kimball model found for the zero value of the f-electron hopping integral t f (including the existence of the devil's staircase structure) persists also at finite values of t f . The critical values of t c f below which the physics of the Falicov-Kimball model dominates are calculated numerically and it is shown that they depend very strongly on the f-electron concentration n f and only very weakly on the Coulomb interaction. In particular, we have found that for strong Coulomb interactions the value of t c f rapidly increases from t c f ~ 0.003 found for n f = 1 / 4 up to relatively large t c f ~ 0.4 found for n f near the half-filled band case n f = 1 / 2. In addition, the complete picture of valence transitions is presented for non-zero t f and strong Coulomb interactions.

  13. Using Motion Pictures to Teach Management: Refocusing the Camera Lens through the Infusion Approach to Diversity

    Science.gov (United States)

    Bumpus, Minnette A.

    2005-01-01

    Motion pictures and television shows can provide mediums to facilitate the learning of management and organizational behavior theories and concepts. Although the motion pictures and television shows cited in the literature cover a broad range of cinematic categories, racial inclusion is limited. The objectives of this article are to document the…

  14. Hop Weighted DV-Hop Localization Algorithm%跳数加权DV-Hop定位算法

    Institute of Scientific and Technical Information of China (English)

    刘凯; 余君君; 谭立雄

    2012-01-01

    A beacon node selection scheme and a DV-Hop localization algorithm based on hop weighted are proposed to improve the positioning performance in this paper. First of all, by setting a threshold value of signal propagation hop,the beacon nodes whose propagation hop are fewer are retained. Then,a beacon node optimization is followed to eliminate unfavourable beacon nodes which are approximately in a line to avoid positioning failure. Besides, based on the relationship between distance estimation error and signal propagation hop derived from Friis model,the hop weighted localization algorithm is obtained. It uses the signal propagation hop as the weighted factors to modify the positioning result that gained through maximum likelihood estimation, which reduces the effect on positioning accuracy brought by distance estimation error. The simulation results show that the proposed method can improve the positioning accuracy by 3% ~5%.%针对DV-Hop定位算法中距离估计误差对定位结果的影响,提出了一种信标节点优选方案和跳数加权DV-Hop定位算法.首先通过设定跳数阈值,保留跳数较少的信标节点,然后剔除近似在一条直线上的信标节点,完成信标节点优选,避免未知节点无法定位的情形.此外,利用Friis模型推导出距离估计误差与信号传播跳数之间的映射关系,采用传播跳数作为加权因子对定位结果进行了修正.仿真结果表明该算法降低了距离估计误差对定位精度的影响,提高了定位精度.

  15. Immunomodulation by the Pseudomonas syringae HopZ type III effector family in Arabidopsis.

    Directory of Open Access Journals (Sweden)

    Jennifer D Lewis

    Full Text Available Pseudomonas syringae employs a type III secretion system to inject 20-30 different type III effector (T3SE proteins into plant host cells. A major role of T3SEs is to suppress plant immune responses and promote bacterial infection. The YopJ/HopZ acetyltransferases are a superfamily of T3SEs found in both plant and animal pathogenic bacteria. In P. syringae, this superfamily includes the evolutionarily diverse HopZ1, HopZ2 and HopZ3 alleles. To investigate the roles of the HopZ family in immunomodulation, we generated dexamethasone-inducible T3SE transgenic lines of Arabidopsis for HopZ family members and characterized them for immune suppression phenotypes. We show that all of the HopZ family members can actively suppress various facets of Arabidopsis immunity in a catalytic residue-dependent manner. HopZ family members can differentially suppress the activation of mitogen-activated protein (MAP kinase cascades or the production of reactive oxygen species, whereas all members can promote the growth of non-virulent P. syringae. Localization studies show that four of the HopZ family members containing predicted myristoylation sites are localized to the vicinity of the plasma membrane while HopZ3 which lacks the myristoylation site is at least partially nuclear localized, suggesting diversification of immunosuppressive mechanisms. Overall, we demonstrate that despite significant evolutionary diversification, all HopZ family members can suppress immunity in Arabidopsis.

  16. Piezo activated mode tracking system for widely tunable mode-hop-free external cavity mid-IR semiconductor lasers

    Science.gov (United States)

    Wysocki, Gerard (Inventor); Tittel, Frank K. (Inventor); Curl, Robert F. (Inventor)

    2010-01-01

    A widely tunable, mode-hop-free semiconductor laser operating in the mid-IR comprises a QCL laser chip having an effective QCL cavity length, a diffraction grating defining a grating angle and an external cavity length with respect to said chip, and means for controlling the QCL cavity length, the external cavity length, and the grating angle. The laser of claim 1 wherein said chip may be tuned over a range of frequencies even in the absence of an anti-reflective coating. The diffraction grating is controllably pivotable and translatable relative to said chip and the effective QCL cavity length can be adjusted by varying the injection current to the chip. The laser can be used for high resolution spectroscopic applications and multi species trace-gas detection. Mode-hopping is avoided by controlling the effective QCL cavity length, the external cavity length, and the grating angle so as to replicate a virtual pivot point.

  17. Hip-Hop Guayaquil: culturas viajeras e identidades locales

    Directory of Open Access Journals (Sweden)

    1999-01-01

    Full Text Available HIP-HOP GUAYAQUIL: CULTURES ITINÉRANTES ET IDENTITES LOCALES. Le hip-hop est un style de musique contemporaine caractérisé par une orchestration d’œuvres lyriques rapées, la superposition de morceaux de musique enregistrés dans le passé par différents artistes, et une instrumentation électronique, tout cela sur des rythmes de basse réguliers et constants. Le hip-hop, musique accompagnée de ses propres danses et de sa mode, est le produit du déplacement et de la transformation d’une variété d’idéologies politiques de la communauté noire qui se constituent à partir de relations qui se modifient entre elles, et en relation avec les cultures dominantes contre lesquelles elles luttent quotidiennement. À l’origine, le hip-hop est lié à des mouvements d’identité de jeunes noirs. Dans cet article, il est intéressant d’étudier le rôle du hip-hop dans la formulation d’une identité entre jeunes métisses et noirs des secteurs populaires de Guayaquil. Cet exemple illustre la nécessité d’inclure dans l’analyse les dimensions politiques des processus de traduction du global au niveau local. El hip-hop es un género de música contemporánea caracterizado por la orquestación de líricas que son rapeadas, superposición de fragmentos de música grabada en el pasado por diferentes artistas, e instrumentación electrónica, todo ello sobre ritmos de bajo regulares y constantes. Como un tipo de música acompañado por sus propias formas de danza y moda, el hip-hop es producto del viaje y la transformación de una variedad de ideologías políticas de la comunidad negra que se constituyen a sí mismas en relaciones cambiantes entre sí y en relación a las culturas dominantes contra las cuales luchan cotidianamente. El hip-hop está ligado, en su contexto originario, a políticas de identidad defendidas por jóvenes negros. Lo que interesa explorar en este artículo es el papel del hip-hop en la formulación de una identidad

  18. Selected pictures of the month

    CERN Multimedia

    Claudia Marcelloni de Oliveira

    View of a single MDT Big Wheel (on side A in UX15 cavern) taken during its last movement immediately after being assembled and just before being connected to the neighbouring TGC1 wheel. Assembly work on the Cathode Strip Chambers on Small Wheel C in building 190. Connecting the services for the Cathode Strip Chambers. The installation of the optical fibers for the readout of the Cathode Strip Chambers on Small Weel C by the Irvine group. Best from our archives: View of the End Cap Calorimeter and TGC big wheel from the Cryostat side A of ATLAS cavern taken on 22 May 2007. The picture above was taken from the platform in the middle, between the Cryostat and the End-Cap. Muriel hopes you all had a great vacation. She herself had a wonderful time sailing in Galicia (North Western Spain). She can be seen here wearing the traditional dress offered to her by "Los Amigos de las Dornas" (Friends of the Dornas -traditional sailing boats used for fishing) - when she became ...

  19. Correlation between hip function and knee kinematics evaluated by three-dimensional motion analysis during lateral and medial side-hopping

    Science.gov (United States)

    Itoh, Hiromitsu; Takiguchi, Kohei; Shibata, Yohei; Okubo, Satoshi; Yoshiya, Shinichi; Kuroda, Ryosuke

    2016-01-01

    [Purpose] Kinematic and kinetic characteristics of the limb during side-hopping and hip/knee interaction during this motion have not been clarified. The purposes of this study were to examine the biomechanical parameters of the knee during side hop and analyze its relationship with clinical measurements of hip function. [Subjects and Methods] Eleven male college rugby players were included. A three-dimensional motion analysis system was used to assess motion characteristics of the knee during side hop. In addition, hip range of motion and muscle strength were evaluated. Subsequently, the relationship between knee motion and the clinical parameters of the hip was analyzed. [Results] In the lateral touchdown phase, the knee was positioned in an abducted and externally rotated position, and increasing abduction moment was applied to the knee. An analysis of the interaction between knee motion and hip function showed that range of motion for hip internal rotation was significantly correlated with external rotation angle and external rotation/abduction moments of the knee during the lateral touchdown phase. [Conclusion] Range of motion for hip internal rotation should be taken into consideration for identifying the biomechanical characteristics in the side hop test results.

  20. Using seafaring simulations and shortest-hop trajectories to model the prehistoric colonization of Remote Oceania.

    Science.gov (United States)

    Montenegro, Álvaro; Callaghan, Richard T; Fitzpatrick, Scott M

    2016-10-24

    The prehistoric colonization of islands in Remote Oceania that began ∼3400 B.P. represents what was arguably the most expansive and ambitious maritime dispersal of humans across any of the world's seas or oceans. Though archaeological evidence has provided a relatively clear picture of when many of the major island groups were colonized, there is still considerable debate as to where these settlers originated from and their strategies/trajectories used to reach habitable land that other datasets (genetic, linguistic) are also still trying to resolve. To address these issues, we have harnessed the power of high-resolution climatic and oceanographic datasets in multiple seafaring simulation platforms to examine major pulses of colonization in the region. Our analysis, which takes into consideration currents, land distribution, wind periodicity, the influence of El Niño Southern Oscillation (ENSO) events, and "shortest-hop" trajectories, demonstrate that (i) seasonal and semiannual climatic changes were highly influential in structuring ancient Pacific voyaging; (ii) western Micronesia was likely settled from somewhere around the Maluku (Molucca) Islands; (iii) Samoa was the most probable staging area for the colonization of East Polynesia; and (iv) although there are major differences in success rates depending on time of year and the occurrence of ENSO events, settlement of Hawai'i and New Zealand is possible from the Marquesas or Society Islands, the same being the case for settlement of Easter Island from Mangareva or the Marquesas.

  1. Hopping conductivity in Mn-doped β-FeSi2 single crystals

    Science.gov (United States)

    Arushanov, E.; Lisunov, K. G.; Vinzelberg, H.; Behr, G.; Schumann, J.; Schmidt, O. G.

    2008-09-01

    The article gives a report on resistivity measurements on Mn-doped p-type FeSi2 single crystals and analyzes the data within the framework of different hopping conductivity models. Both the Mott [N. Mott and E. A. Davies, Electron Processes in Non-Crystalline Materials (Clarendon, Oxford, 1979)] and the Shklovskii-Efros [B. I. Shklovskii and A. L. Efros, Electronic Properties o0066 Doped Semiconductors (Springer, Berlin, 1984)] regimes of the variable-range hopping (VRH) conductivity are observed. It is shown that the temperature dependence of the resistivity of Mn-doped β-FeSi2 crystals, which follows a VRH conduction mechanism, can be expressed by a scaling expression of the form ln(ρ /ρ0)=Af(T /Tx). The characteristic and transition temperatures, as well as the complete set of parameters describing the properties of the localized holes (the localization radius, the dielectric permittivity, the width of the Coulomb gap Δ, and the values of the density of states at the Fermi level) are determined. The data above indicate existence of a rigid gap δ in the spectrum of the DOS in addition to Δ and point out to the polaronic nature of the charge carriers in the investigated compound.

  2. Hopping conductivity and insulator-metal transition in films of touching semiconductor nanocrystals

    Science.gov (United States)

    Fu, Han; Reich, K. V.; Shklovskii, B. I.

    2016-03-01

    This paper is focused on the variable-range hopping of electrons in semiconductor nanocrystal (NC) films below the critical doping concentration nc at which it becomes metallic. The hopping conductivity is described by the Efros-Shklovskii law, which depends on the localization length of electrons. We study how the localization length grows with the doping concentration n in the film of touching NCs. For that we calculate the electron transfer matrix element t (n ) between neighboring NCs for two models when NCs touch by small facets or just one point. We study two sources of disorder: variations of NC diameters and random Coulomb potentials originating from random numbers of donors in NCs. We use the ratio of t (n ) to the disorder-induced NC level dispersion to find the localization length of electrons due to the multistep elastic co-tunneling process. We found three different phases at n

  3. Excess-Electron Transfer in DNA by a Fluctuation-Assisted Hopping Mechanism.

    Science.gov (United States)

    Lin, Shih-Hsun; Fujitsuka, Mamoru; Majima, Tetsuro

    2016-02-04

    The dynamics of excess-electron transfer in DNA has attracted the attention of scientists from all kinds of research fields because of its importance in biological processes. To date, several studies on excess-electron transfer in consecutive adenine (A):thymine (T) sequences in donor-DNA-acceptor systems have been published. However, the reported excess-electron transfer rate constants for consecutive T's are in the range of 10(10)-10(11) s(-1) depending on the photosensitizing electron donor, which provides various driving forces for excess-electron injection into DNA. In this study, we employed a strongly electron-donating photosensitizer, a dimer of 3,4-ethylenedioxythiophene (2E), and an electron acceptor, diphenylacetylene (DPA), to synthesize a series of modified DNA oligomers (2-Tn, n = 3-6) in order to investigate the excess-electron transfer dynamics in these donor-DNA-acceptor systems using femtosecond laser flash photolysis. The relation between the free energy change for charge injection and the excess-electron transfer rate among consecutive T's provided an intrinsic excess-electron hopping rate constant of (3.8 ± 1.5) × 10(10) s(-1) in the DNA, which is consistent with the fluctuation frequency of the DNA sugar backbone and bases (3.3 × 10(10) s(-1)). Thus, we discuss the effect of structural fluctuations on the excess-electron hopping in DNA.

  4. Two-dimensional quantum percolation with binary non-zero hopping integrals

    Science.gov (United States)

    Dillon Thomas, Brianna; Nakanishi, Hisao

    In a previous work [Dillon and Nakanishi, Eur.Phys.J B 87, 286 (2014)], we calculated the transmission coefficient of the two-dimensional quantum percolation problem and mapped out in detail the three regimes of localization, i.e., exponentially localized, power-law localized, and delocalized which had been proposed earlier [Islam and Nakanishi, Phys.Rev. E 77, 061109 (2008)]. We now consider a variation on quantum percolation in which the hopping integral (Vdiluted) associated with bonds that connect to at least one diluted site is non-zero but a fraction of the hopping integral (Vfull=1) between non-diluted sites. We study the latter model by calculating quantities such as the transmission coefficient and the inverse participation ratio and find the original quantum percolation results to be stable over a wide range of energy. In particular, except in the immediate neighborhood of the band center (where increasing Vdiluted to just 0.02*Vfull appears to eliminate localization effects), increasing Vdiluted only shifts the boundaries between the 3 regimes but does not eliminate them until the Vdiluted reaches 20

  5. Magazine Picture Collage in Group Supervision

    Science.gov (United States)

    Shepard, Blythe C.; Guenette, Francis L.

    2010-01-01

    A magazine picture collage activity was used with three female counsellor education students as a vehicle to support them in processing their experience as counsellors in training. The use of magazine picture collage in group supervision is described, and the benefits and challenges are presented. The collages served as jumping-off points for…

  6. Picture-Word Interference Is Semantically Based

    Science.gov (United States)

    Rosinski, Richard R.

    1977-01-01

    Analysis of the performance of second-, fourth-, sixth-grade, and college-level subjects on picture-word interference tasks indicated that distractor words belonging to the same semantic category as pictures produced more interference than either unrelated words or nonsense trigrams. (Author/JMB)

  7. Wigner method dynamics in the interaction picture

    DEFF Research Database (Denmark)

    Møller, Klaus Braagaard; Dahl, Jens Peder; Henriksen, Niels Engholm

    1994-01-01

    The possibility of introducing an interaction picture in the semiclassical Wigner method is investigated. This is done with an interaction Picture description of the density operator dynamics as starting point. We show that the dynamics of the density operator dynamics as starting point. We show ...... integration of the Schrodinger equation....

  8. An MEG study of picture naming

    NARCIS (Netherlands)

    Levelt, W.J.M.; Praamstra, P.; Meyer, A.S.; Helenius, P.I.; Salmelin, R.

    1998-01-01

    The purpose of this study was to relate a psycholinguistic processing model of picture naming to the dynamics of cortical activation during picture naming. The activation was recorded from eight Dutch subjects with a whole-head neuromagnetometer. The processing model, based on extensive naming

  9. The Untapped Potential of Picture Books

    Science.gov (United States)

    Hager, Stephanie

    2015-01-01

    This article discusses the role picture books play in helping young writers. Third-grade students were read engaging picture books for the sole purpose of noticing and naming different features they encountered during the read-alouds. Students were able to recognize the tools many authors and illustrators use such as onomatopoeia, varied font…

  10. USING PICTURES IN THE LANGUAGE CLASSROOM

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    Visuals are advantageous to language teaching and learning.Effective use of pictures in the lan-guage classroom contributes to stimulate the students’ imagination and creativity,enhance their basic lan-guage skills and heighten their communicative competence.This Paper will present some techniques andactivities with pictures for use in the language class.

  11. The Functions of Pictures in Problem Solving

    Science.gov (United States)

    Elia, Iliada; Philippou, George

    2004-01-01

    In the present study, we assert that pictures serve four functions in problem solving: decorative, representational, organizational and informational. We, therefore, investigate the effects of pictures based on their functions in mathematical problem solving (MPS), by high achievement students of Grade 6 in Cyprus, in a communication setting. A…

  12. Attitudes toward Motion Pictures among College Students.

    Science.gov (United States)

    Austin, Bruce A.

    Several reasons for studying motion pictures and patrons' attitudes toward them include the following: (1) current data show that motion pictures account for 53% of the total United States spectator amusement expenditures; (2) the average weekly United States movie attendance has plummeted by more than half since 1930; (3) despite this decline,…

  13. Parallel processing for digital picture comparison

    Science.gov (United States)

    Cheng, H. D.; Kou, L. T.

    1987-01-01

    In picture processing an important problem is to identify two digital pictures of the same scene taken under different lighting conditions. This kind of problem can be found in remote sensing, satellite signal processing and the related areas. The identification can be done by transforming the gray levels so that the gray level histograms of the two pictures are closely matched. The transformation problem can be solved by using the packing method. Researchers propose a VLSI architecture consisting of m x n processing elements with extensive parallel and pipelining computation capabilities to speed up the transformation with the time complexity 0(max(m,n)), where m and n are the numbers of the gray levels of the input picture and the reference picture respectively. If using uniprocessor and a dynamic programming algorithm, the time complexity will be 0(m(3)xn). The algorithm partition problem, as an important issue in VLSI design, is discussed. Verification of the proposed architecture is also given.

  14. Rapid induction of false memory for pictures.

    Science.gov (United States)

    Weinstein, Yana; Shanks, David R

    2010-07-01

    Recognition of pictures is typically extremely accurate, and it is thus unclear whether the reconstructive nature of memory can yield substantial false recognition of highly individuated stimuli. A procedure for the rapid induction of false memories for distinctive colour photographs is proposed. Participants studied a set of object pictures followed by a list of words naming those objects, but embedded in the list were names of unseen objects. When subsequently shown full colour pictures of these unseen objects, participants consistently claimed that they had seen them, while discriminating with high accuracy between studied pictures and new pictures whose names did not appear in the misleading word list. These false memories can be reported with high confidence as well as the feeling of recollection. This new procedure allows the investigation of factors that influence false memory reports with ecologically valid stimuli and of the similarities and differences between true and false memories.

  15. Fast frequency hopping codes applied to SAC optical CDMA network

    Science.gov (United States)

    Tseng, Shin-Pin

    2015-06-01

    This study designed a fast frequency hopping (FFH) code family suitable for application in spectral-amplitude-coding (SAC) optical code-division multiple-access (CDMA) networks. The FFH code family can effectively suppress the effects of multiuser interference and had its origin in the frequency hopping code family. Additional codes were developed as secure codewords for enhancing the security of the network. In considering the system cost and flexibility, simple optical encoders/decoders using fiber Bragg gratings (FBGs) and a set of optical securers using two arrayed-waveguide grating (AWG) demultiplexers (DeMUXs) were also constructed. Based on a Gaussian approximation, expressions for evaluating the bit error rate (BER) and spectral efficiency (SE) of SAC optical CDMA networks are presented. The results indicated that the proposed SAC optical CDMA network exhibited favorable performance.

  16. Lattice Gauge Quantum Simulation via State-Dependent Hopping

    DEFF Research Database (Denmark)

    Salami Dehkharghani, Amin

    2017-01-01

    We develop a quantum simulator architecture that is suitable for the simulation of U(1) Abelian gauge theories such as quantum electrodynamics. Our approach relies on the ability to control the hopping of a particle through a barrier by means of the internal quantum states of a neutral or charged...... impurity-particle sitting at the barrier. This scheme is highly experimentally feasible, as the correlated hopping does not require fine-tuning of the intra- and inter-species interactions. We investigate the applicability of the scheme in a double well potential, which is the basic building block...... of the simulator, both at the single-particle and the many-body mean-field level. Moreover, we evaluate its performance for different particle interactions and trapping, and, specifically for atom-ion systems, in the presence of micro-motion....

  17. O CIRCUITO HIP HOP NA REGIÃO DE CAMPINAS

    Directory of Open Access Journals (Sweden)

    Cristiano Nunes Alves

    2013-01-01

    Full Text Available This paper examines the thickness of the circuit hip hop in the region of Campinas and it’s a part of an inventory made in fifteen cities of the region, between 2003 and 2005. The circuit hip hop growing in Campinas since the decade of 1980, and has been expanding in the context of urbanization and metropolis. We noticed some residual cultural component in places involves, among others, the alternative production involved by a technically and territorial division of labor spurred by circuits upside of information. The culture of the streets and these circuits, survive to the urban division and fragmentation. It is, therefore, a study of the region of Campinas as a place that houses technical, informational and communicational densities. We analyzed geographical conditions of contemporary life in this region, inquiring about the communication and the informational components in the use of the territory.

  18. Hip-Hop:屁股不会说谎

    Institute of Scientific and Technical Information of China (English)

    董乐

    2006-01-01

    <正> Hip 是屁股,Hop 是跳跃的意思,中文习惯称为"嘻哈"。Hip-Hop 是指一种20世纪70年代末产生于美国街头的黑人文化,主要流行于纽约的南布郎士、布鲁克林区等一些黑人贫困地区。它包括音乐、舞蹈、涂鸦、刺青和衣着,但更重要的是精神,是"嬉笑怒骂"。这一切源于对真实的追求与对

  19. Hip-Hop(e): The Cultural Practice and Critical Pedagogy of International Hip-Hop. Adolescent Cultures, School, and Society. Volume 56

    Science.gov (United States)

    Porfilio, Brad J., Ed.; Viola, Michael J., Ed.

    2012-01-01

    Illuminating hip-hop as an important cultural practice and a global social movement, this collaborative project highlights the emancipatory messages and cultural work generated by the organic intellectuals of global hip-hop. Contributors describe the social realities--globalization, migration, poverty, criminalization, and racism--youth are…

  20. New hop (Humulus lupulus L. cultivars from Romania

    Directory of Open Access Journals (Sweden)

    Alexandru SALONTAI

    1985-08-01

    Full Text Available The research staff of the Agronomy Institute of Cluj-Napoca breeded the first Romanian hop cultivars officially approved in 1984 by the State Commission for the Testing and Approval of Plant Varieties. The new Humulus lupulus varieties are cv. "Napoca'l", cv. "Aroma" and cv. "Transilvania". The selection method, origin, biological characteristics, productivity and some technological qualities of the new cultivars are discussed in the paper.

  1. HPLC Analysis of alpha and beta Acids in Hops

    Energy Technology Data Exchange (ETDEWEB)

    Danenhower, Travis [Kutztown University; Force, Leyna [Kutztown University; Petersen, Kenneth [Kutztown University; Betts, Thomas [Kutztown University; Baker, Gary A [ORNL

    2008-01-01

    Early in brewing history, a variety of herbs and spices (such as coriander, rosemary, yarrow, and bog myrtle) were used to flavor beer (1). It is evident, from the Bavarian Purity Law of 1516, that a major shift in beer flavoring occurred around the middle of the second millennium. This law declared that only three ingredients could be used to brew beer: barley, water, and hops (1), thus eliminating other spices from German beer. (The importance of yeast had not yet been uncovered.)

  2. Implementation of Low Power Multi-hop Wireless Sensor Network

    OpenAIRE

    Zhou Jianhong; Ma Maode; Fengyong

    2016-01-01

    In this paper, the multi-hop wireless sensor network is created, which is realized by Micaz and Mib520 Board using TinyOS and Cygwin. The mote transmission mode is engaged and off-the-shelf protocols and algorithm, RSSI and PDR, are applied in this wireless network and the performance is improved. Several experiments are proposed to set standard RSSI threshold value to allow the user to send packet with efficient power level.

  3. 多维性感之Hip-Hop

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    “奥尼尔说他是NBA历史上最有统治力量的,他错了,现在统治NBA的是Hip-Hop,我的会员们都有数十年的NBA现场观战经验,而现在他们对NBA的概念就是,‘这是个恶棍联盟’”

  4. 时尚活力的Hip-hop

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    什么是Hip-hop Hip-hop起源于上世纪70年代中期的美国纽约,这个词语已经成为新生代族群的代名词。Hip-hop不是一个时代的热潮,它是一种感染了一代又一代的文化。总的来说Hip-hop是Hip-hop文化的统

  5. HIP HOP: A CORPORAL PRACTICE (EXPRESSION) THAT TERRITORIALIZE MEDELLIN CITY

    OpenAIRE

    Hincapié, Astrid

    2014-01-01

    This article is part of the research Appropriation of dancing urban corporal practices by young people of the city of Medellin – Commune 13 (Col.), which was developed in the master in Motricity and human development of the University of Antioquia. In this article we analyze, through an urban ethnography, how young people from the city create a cultural territory by practicing Hip-Hop. An artistic expression that develops in the middle of the tensions that takes place among young people, inst...

  6. Understanding hopping transport and thermoelectric properties of conducting polymers

    OpenAIRE

    Ihnatsenka, Siarhei; Crispin, Xavier; Zozoulenko, Igor

    2015-01-01

    We calculate the conductivity sigma and the Seebeck coefficient S for the phonon-assisted hopping transport in conducting polymers poly(3,4-ethylenedioxythiophene) or PEDOT, experimentally studied by Bubnova et al. [J. Am. Chem. Soc. 134, 16456 (2012)]. We use the Monte Carlo technique as well as the semianalytical approach based on the transport energy concept. We demonstrate that both approaches show a good qualitative agreement for the concentration dependence of sigma and S. At the same t...

  7. Hsp70/Hsp90 organising protein (hop): beyond interactions with chaperones and prion proteins.

    Science.gov (United States)

    Baindur-Hudson, Swati; Edkins, Adrienne L; Blatch, Gregory L

    2015-01-01

    The Hsp70/Hsp90 organising protein (Hop), also known as stress-inducible protein 1 (STI1), has received considerable attention for diverse cellular functions in both healthy and diseased states. There is extensive evidence that intracellular Hop is a co-chaperone of the major chaperones Hsp70 and Hsp90, playing an important role in the productive folding of Hsp90 client proteins. Consequently, Hop is implicated in a number of key signalling pathways, including aberrant pathways leading to cancer. However, Hop is also secreted and it is now well established that Hop also serves as a receptor for the prion protein, PrP(C). The intracellular and extracellular forms of Hop most likely represent two different isoforms, although the molecular determinants of these divergent functions are yet to be identified. There is also a growing body of research that reports the involvement of Hop in cellular activities that appear independent of either chaperones or PrP(C). While Hop has been shown to have various cellular functions, its biological function remains elusive. However, recent knockout studies in mammals suggest that Hop has an important role in embryonic development. This review provides a critical overview of the latest molecular, cellular and biological research on Hop, critically evaluating its function in healthy systems and how this function is adapted in diseases states.

  8. Changes in the hop-derived volatile profile upon lab scale boiling.

    Science.gov (United States)

    Praet, Tatiana; Van Opstaele, Filip; Steenackers, Bart; De Brabanter, Joseph; De Vos, Dirk; Aerts, Guido; De Cooman, Luc

    2015-09-01

    Hop terpenes might be oxidized during kettle boiling into more water soluble compounds that could contribute to 'hoppy' aroma of kettle hopped lager beers. Our current research proves that the boiling process induces significant changes in the hop oil volatile profile. The discrimination between volatile profiles of unboiled and boiled hop essential oil was evaluated via principal component and cluster analysis (PCA and CA). HS-SPME-GC-MS analysis revealed quantitative changes (e.g. increases in the levels of oxygenated α-humulene and β-caryophyllene derivatives) as well as qualitative changes (i.e. detection of compounds, not found in unboiled hop essential oil) in the hop oil volatile profile upon boiling. Many of these compounds were previously found in lager beer and may therefore contribute to beer flavor. Interestingly, the analytical difference between unboiled and boiled hop essential oil proved to be more pronounced as the initial hop essential oil concentration used for boiling was increased. In addition, lager beers spiked with boiled hop oil were described as 'hoppy/spicy' during sensory evaluations. Therefore, the newly formed products and hop oil constituents that are characterized by an increased recovery after boiling, are candidate compounds for 'hoppy' aroma in real brewing practice. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Lack of association between gastric cancer and hopQ alleles in Helicobacter pylori

    Directory of Open Access Journals (Sweden)

    Kazemi Elham

    2016-01-01

    Full Text Available Helicobacter pylori use a number of mechanisms to survive in the stomach lumen. The presence of these bacteria in the stomach can lead to gastritis and reduction in stomach acid production. Acute inflammation can directly damage to the peripheral cells that are responsible for the secretion of acid. The risk of developing gastric carcinoma is associated to heterogeneity of Helicobacter pylori virulence factors (such as cagA. The HopQ is one of the outer membrane proteins involved in bacterial adherence to gastric mucosa and has been suggested to also play a role in the virulence of H. pylori. This gene has been shown in two types. The purpose of the current study was to investigate the association between different H. pylori virulence hopQ alleles (types I and II and patients with gastroduodenal disorders. For this purpose 58 stomach biopsies the of patients with gastric cancer and 100 saliva samples from healthy individuals were collected. Then genomic DNA was purified and PCR for was done for desired genes via specific primers. The H. pylori infections were diagnosed by PCR for GlmM gene. Then frequencies of hopQI+, hopQII+ and hopQI+ hopQII+ genotypes were determined in H. pylori infected cases. Statistical analysis showed that there were not significant differences between healthy and diseased ones for genotypes hopQI+, hopQII+ and hopQI+ hopQII+.

  10. Duplex Schemes in Multiple Antenna Two-Hop Relaying

    Directory of Open Access Journals (Sweden)

    Anja Klein

    2008-04-01

    Full Text Available A novel scheme for two-hop relaying defined as space division duplex (SDD relaying is proposed. In SDD relaying, multiple antenna beamforming techniques are applied at the intermediate relay station (RS in order to separate downlink and uplink signals of a bi-directional two-hop communication between two nodes, namely, S1 and S2. For conventional amplify-and-forward two-hop relaying, there appears a loss in spectral efficiency due to the fact that the RS cannot receive and transmit simultaneously on the same channel resource. In SDD relaying, this loss in spectral efficiency is circumvented by giving up the strict separation of downlink and uplink signals by either time division duplex or frequency division duplex. Two novel concepts for the derivation of the linear beamforming filters at the RS are proposed; they can be designed either by a three-step or a one-step concept. In SDD relaying, receive signals at S1 are interfered by transmit signals of S1, and receive signals at S2 are interfered by transmit signals of S2. An efficient method in order to combat this kind of interference is proposed in this paper. Furthermore, it is shown how the overall spectral efficiency of SDD relaying can be improved if the channels from S1 and S2 to the RS have different qualities.

  11. Performance Analysis of RF-FSO Multi-Hop Networks

    KAUST Repository

    Makki, Behrooz

    2017-05-12

    We study the performance of multi-hop networks composed of millimeter wave (MMW)-based radio frequency (RF) and free-space optical (FSO) links. The results are obtained in the cases with and without hybrid automatic repeat request (HARQ). Taking the MMW characteristics of the RF links into account, we derive closed-form expressions for the network outage probability. We also evaluate the effect of various parameters such as power amplifiers efficiency, number of antennas as well as different coherence times of the RF and the FSO links on the system performance. Finally, we present mappings between the performance of RF- FSO multi-hop networks and the ones using only the RF- or the FSO-based communication, in the sense that with appropriate parameter settings the same outage probability is achieved in these setups. The results show the efficiency of the RF-FSO setups in different conditions. Moreover, the HARQ can effectively improve the outage probability/energy efficiency, and compensate the effect of hardware impairments in RF-FSO networks. For common parameter settings of the RF-FSO dual- hop networks, outage probability 10^{-4} and code rate 3 nats-per-channel-use, the implementation of HARQ with a maximum of 2 and 3 retransmissions reduces the required power, compared to the cases with no HARQ, by 13 and 17 dB, respectively.

  12. Estrogens and congeners from spent hops (Humulus lupulus).

    Science.gov (United States)

    Chadwick, Lucas R; Nikolic, Dejan; Burdette, Joanna E; Overk, Cassia R; Bolton, Judy L; van Breemen, Richard B; Fröhlich, Roland; Fong, Harry H S; Farnsworth, Norman R; Pauli, Guido F

    2004-12-01

    Estrogenicity-directed fractionation of a methanol extract of the strobiles of Humulus lupulus that had been extracted previously with supercritical CO(2), known as "spent hops", led to the isolation and identification of 22 compounds including 12 prenylated chalcones (1-8, 10-13), five prenylflavanones (14-17), 4-hydroxybenzaldehyde (18), sitosterol-3-O-beta-glucopyranoside (19), humulinone (20), and cohumulinone (21). In addition, the prenylated chalcone xanthohumol C (9a) was obtained as a 6:1 mixture along with its 1' ',2' '-dihydro derivative (9b). Three new chalcones (4, 11, 12) and four previously unreported constituents of hops (5, 6, 9b, 13) are reported. The structures of the new compounds were determined through a combination of spectrometric techniques including 1D and 2D NMR, HRESIMS, and ESIMS-MS. Full 1H NMR spin system analyses were performed to characterize the higher-order glucopyranosyl, prenyl, and chalcone B-ring spectra of the isolates. The principle estrogen 8-prenylnaringenin (15) from hops is an artifact formed along with its positional isomer 6-prenylnaringenin (16) through the spontaneous isomerization of the pro-estrogenic chalcone DMX (7).

  13. Critical appraisal of the fewest switches algorithm for surface hopping

    Science.gov (United States)

    Granucci, Giovanni; Persico, Maurizio

    2007-04-01

    In this paper the authors address the problem of internal consistency in trajectory surface hopping methods, i.e., the requirement that the fraction of trajectories running on each electronic state equals the probabilities computed by the electronic time-dependent Schrödinger equation, after averaging over all trajectories. They derive a formula for the hopping probability in Tully's "fewest switches" spirit that would yield a rigorously consistent treatment. They show the relationship of Tully's widely used surface hopping algorithm with the "exact" prescription that cannot be applied when running each trajectory independently. They also bring out the connection of the consistency problem with the coherent propagation of the electronic wave function and the artifacts caused by coherent Rabi-type oscillations of the state probabilities in weak coupling regimes. A real molecule (azobenzene) and two ad hoc models serve as examples to illustrate the above theoretical arguments. Following a proposal by Truhlar's group [Zhu et al., J. Chem. Phys. 121, 7658 (2004) Zhu et al., J. Chem. Theory Comput. 1, 527 (2005)], they apply a decoherence correction to the state probabilities, in conjunction with Tully's algorithm, and they obtain satisfactory results in terms of internal consistency and of agreement with the outcomes of quantum wave packet calculations.

  14. Resonant enhancement of thermoelectric properties by correlated hopping for the Falicov-Kimball model on Bethe lattice

    Science.gov (United States)

    Dobushovskyi, D. A.; Shvaika, A. M.; Zlatić, V.

    2017-03-01

    The effect of correlated hopping on the charge and heat transport of strongly correlated particles is studied for the Falicov-Kimball model on the Bethe lattice. Exact solutions for the one-particle density of states (DOS) and two-particle transport function (the "quasiparticle" scattering time) are derived using dynamical mean-field theory. For a wide range of the correlated hopping, the transport function exhibits singularities due to the resonant two-particle contribution, whereas the one-particle DOS does not show any anomalous features. By tuning the number of itinerant electrons, so as to bring the Fermi level close to the resonant frequency, we get a large increase of the electrical and thermal conductivities, and the thermoelectric power. When the hopping amplitude between the occupied sites is reduced sufficiently, the itinerant electrons localize in the clusters of sites occupied by f electrons. This gives rise to an additional narrow band in the DOS between the lower and upper Hubbard bands but has only a minor effect on the thermoelectric properties.

  15. An Introduction to Recording, Editing, and Streaming Picture-in-Picture Ultrasound Videos.

    Science.gov (United States)

    Rajasekaran, Sathish; Hall, Mederic M; Finnoff, Jonathan T

    2016-08-01

    This paper describes the process by which high-definition resolution (up to 1920 × 1080 pixels) ultrasound video can be captured in conjunction with high-definition video of the transducer position (picture-in-picture). In addition, we describe how to edit the recorded video feeds to combine both feeds, and to crop, resize, split, stitch, cut, annotate videos, and also change the frame rate, insert pictures, edit the audio feed, and use chroma keying. We also describe how to stream a picture-in-picture ultrasound feed during a videoconference. Copyright © 2016 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

  16. A Hop-by-Hop Congestion-Aware Routing Protocol for Heterogeneous Mobile Ad-hoc Networks

    CERN Document Server

    Narasimhan, B

    2009-01-01

    In Heterogeneous mobile ad hoc networks (MANETs) congestion occurs with limited resources. Due to the shared wireless channel and dynamic topology, packet transmissions suffer from interference and fading. In heterogeneous ad hoc networks, throughput via a given route is depending on the minimum data rate of all its links. In a route of links with various data rates, if a high data rate node forwards more traffic to a low data rate node, there is a chance of congestion, which leads to long queuing delays in such routes. Since hop count is used as a routing metric in traditional routing, it do not adapt well to mobile nodes. A congestion-aware routing metric for MANETs should incorporate transmission capability, reliability, and congestion around a link. In this paper, we propose to develop a hop-by-hop congestion aware routing protocol which employs a combined weight value as a routing metric, based on the data rate, queuing delay, link quality and MAC overhead. Among the discovered routes, the route with min...

  17. Reliable Multicast MAC Protocol for IEEE 802.11 Wireless LANs with Extended Service Range

    Science.gov (United States)

    Choi, Woo-Yong

    2011-11-01

    In this paper, we propose the efficient reliable multicast MAC protocol by which the AP (Access Point) can transmit reliably its multicast data frames to the recipients in the AP's one-hop or two-hop transmission range. The AP uses the STAs (Stations) that are directly associated with itself as the relays for the data delivery to the remote recipients that cannot be reached directly from itself. Based on the connectivity information among the recipients, the reliable multicast MAC protocol optimizes the number of the RAK (Request for ACK) frame transmissions in a reasonable computational time. Numerical examples show that our proposed MAC protocol significantly enhances the MAC performance compared with the BMMM (Batch Mode Multicast MAC) protocol that is extended to support the recipients that are in the AP's one-hop or two-hop transmission range in IEEE 802.11 wireless LANs.

  18. Long range hops and the pair annihilation reaction A+A-->0: renormalization group and simulation.

    Science.gov (United States)

    Vernon, Daniel C

    2003-10-01

    A simple example of a nonequilibrium system for which fluctuations are important is a system of particles which diffuse and may annihilate in pairs on contact. The renormalization group can be used to calculate the time dependence of the density of particles, and provides both an exact value for the exponent governing the decay of particles and an epsilon expansion for the amplitude of this power law. When the diffusion is anomalous, as when the particles perform Lévy flights, the critical dimension depends continuously on the control parameter for the Lévy distribution. The epsilon expansion can then become an expansion in a small parameter. We present the renormalization group calculation and compare these results with those of a simulation.

  19. Droppin’ Knowledge on Race: Hip-Hop, White Adolescents, and Anti-Racism Education

    Directory of Open Access Journals (Sweden)

    Steven Netcoh

    2013-10-01

    Full Text Available In this essay, the author examines how Hip-Hop can be mobilized in anti-racism educational initatives.  The author claims that existing research on Hip-Hop and white adolescents suggests a negative corrleation between white youths' engagement with Hip-Hop and their understanding of how race and racism function in American society.  In response to this research, the author argues Hip-Hop's diverse racial discourses and ideologies must be made the subject of direct and critical inquiry in secondary and post-secondary classrooms to maximize its democratic potential.  The author outlines specific approaches for how teachers can employ Hip-Hop in anti-racism curricula in secondary and post-secondary classrooms.  Collectively, the essay serves as a preliminary investigation of Hip-Hop pedagogies of race and whiteness.

  20. «Hip hop culture»: a review of its potential as an educational tool

    Directory of Open Access Journals (Sweden)

    Alberto RODRÍGUEZ ÁLVAREZ

    2014-12-01

    Full Text Available  This paper reviews the meaning of «hip hop culture» as a contemporary musical phenomenon, and how rap is a feature of the social and educational activities aimed at youth. The purpose of it is to show the evolution of hip hop, its agents, its practices, and its relationship with the world of the music industry and cultural action.It provides useful information on the contents of the Spanish rap lyrics that have been analyzed to check the messages transmitted, the ideas and references to the precepts legitimized in «hip hop culture». This is an approach to the idea that hip hop is a means of expression of social concerns and values that identify the hip hop culture. So, this study aims to provide a better knowledge of some educational experiences that have used hip hop as a tool to promote change in neighbourhoods, social groups or youth groups.

  1. Deterministic Multi-hop Controlled Teleportation of Arbitrary Single-Qubit State

    Science.gov (United States)

    Peng, Jia-yin; Bai, Ming-qiang; Mo, Zhi-wen

    2017-10-01

    Multi-hop teleportation is of great significance due to long-distance delivery of quantum information and wireless quantum communication networks. In existing protocols of multi-hop teleportation, the more nodes, the smaller the success probability. In this paper, fusing the ideas of multi-hop teleportation and controlled teleportation, we put forward a scheme for implementing multi-hop controlled teleportation of single-qubit state. A set of ingenious three-qubit non-maximally entangled states are constructed to serve as the quantum channels. The information is perfectly transmitted hop by hop through teleportation under the control of the supervisors. Unit success probability can be achieved independent of channel's entanglement degree and the number of intermediate nodes. Only Pauli operations, single-qubit rotation, Hadamard gate, controlled-NOT gate, Bell-state measurement and single-qubit measurement are used in our scheme, so this scheme is easily realized in physical experiment.

  2. Blind Compressed Sensing Parameter Estimation of Non-cooperative Frequency Hopping Signal

    Directory of Open Access Journals (Sweden)

    Chen Ying

    2016-10-01

    Full Text Available To overcome the disadvantages of a non-cooperative frequency hopping communication system, such as a high sampling rate and inadequate prior information, parameter estimation based on Blind Compressed Sensing (BCS is proposed. The signal is precisely reconstructed by the alternating iteration of sparse coding and basis updating, and the hopping frequencies are directly estimated based on the results. Compared with conventional compressive sensing, blind compressed sensing does not require prior information of the frequency hopping signals; hence, it offers an effective solution to the inadequate prior information problem. In the proposed method, the signal is first modeled and then reconstructed by Orthonormal Block Diagonal Blind Compressed Sensing (OBD-BCS, and the hopping frequencies and hop period are finally estimated. The simulation results suggest that the proposed method can reconstruct and estimate the parameters of noncooperative frequency hopping signals with a low signal-to-noise ratio.

  3. Hole hopping rates in single strand oligonucleotides

    Energy Technology Data Exchange (ETDEWEB)

    Borrelli, Raffaele [Dipartimento di Scienze Agrarie, Forestali e Alimentari, Università di Torino, Largo Paolo Braccini 2, I-10095 Grugliasco, TO (Italy); Capobianco, Amedeo [Dipartimento di Chimica e Biologia, Università di Salerno, Via Giovanni Paolo II, I-84084 Fisciano, SA (Italy); Peluso, Andrea, E-mail: apeluso@unisa.it [Dipartimento di Chimica e Biologia, Università di Salerno, Via Giovanni Paolo II, I-84084 Fisciano, SA (Italy)

    2014-08-31

    Highlights: • DNA hole transfer rates have been computed. • Delocalized adenine domains significantly affect hole transfer rates in DNA. • Franck–Condon weighted density of state from DFT normal modes. • DNA application in molecular electronics. - Abstract: The rates of hole transfer between guanine and adenine in single strand DNA have been evaluated by using Fermi’s golden rule and Kubo’s generating function approach for the Franck–Condon weighted density of states. The whole sets of the normal modes and vibrational frequencies of the two nucleobases, obtained at DFT/B3LYP level of calculation, have been considered in computations. The results show that in single strand the pyramidalization/planarization mode of the amino groups of both nucleobases plays the major role. At room temperature, the Franck–Condon density of states extends over a wide range of hole site energy difference, 0–1 eV, giving some hints about the design of oligonucleotides of potential technological interest.

  4. Holographic picture of heavy vector meson melting

    Energy Technology Data Exchange (ETDEWEB)

    Braga, Nelson R.F.; Diles, Saulo [Universidade Federal do Rio de Janeiro, Instituto de Fisica, Rio de Janeiro, RJ (Brazil); Martin Contreras, Miguel Angel [Universidad de los Andes, High Energy Group, Department of Physics, Bogota (Colombia)

    2016-11-15

    The fraction of heavy vector mesons produced in a heavy ion collision, as compared to a proton-proton collision, serves as an important indication of the formation of a thermal medium, the quark-gluon plasma. This sort of analysis strongly depends on understanding the thermal effects of a medium like the plasma on the states of heavy mesons. In particular, it is crucial to know the temperature ranges where they undergo a thermal dissociation, or melting. AdS/QCD models are know to provide an important tool for the calculation of hadronic masses, but in general are not consistent with the observation that decay constants of heavy vector mesons decrease with excitation level. It has recently been shown that this problem can be overcome using a soft wall background and introducing an extra energy parameter, through the calculation of correlation functions at a finite position of anti-de Sitter space. This approach leads to the evaluation of masses and decay constants of S wave quarkonium states with just one flavor dependent and one flavor independent parameter. Here we extend this more realistic model to finite temperatures and analyze the thermal behavior of the states 1S, 2S and 3S of bottomonium and charmonium. The corresponding spectral function exhibits a consistent picture for the melting of the states where, for each flavor, the higher excitations melt at lower temperatures. We estimate for these six states the energy ranges in which the heavy vector mesons undergo a transition from a well-defined peak in the spectral function to complete melting in the thermal medium. A very clear distinction between the heavy flavors emerges, with the bottomonium state Υ(1S) surviving a deconfinement transition at temperatures much larger than the critical deconfinement temperature of the medium. (orig.)

  5. An Improved DY-Hop Localization Algorithm with Reduced Node Location Error for Wireless Sensor Networks

    Science.gov (United States)

    Chen, Hongyang; Sezaki, Kaoru; Deng, Ping; So, Hing Cheung

    In this paper, we propose a new localization algorithm and improve the DV-Hop algorithm by using a differential error correction scheme that is designed to reduce the location error accumulated over multiple hops. This scheme needs no additional hardware support and can be implemented in a distributed way. The proposed method can improve location accuracy without increasing communication traffic and computing complexity. Simulation results show the performance of the proposed algorithm is superior to that of the DV-Hop algorithm.

  6. New Class of Optimal Frequency-Hopping Sequences by Polynomial Residue Class Rings

    CERN Document Server

    Ma, Wenping

    2010-01-01

    In this paper, using the theory of polynomial residue class rings, a new construction is proposed for frequency hopping patterns having optimal Hamming autocorrelation with respect to the well-known $Lempel$-$Greenberger$ bound. Based on the proposed construction, many new $Peng$-$Fan$ optimal families of frequency hopping sequences are obtained. The parameters of these sets of frequency hopping sequences are new and flexible.

  7. Impaired picture sequencing ability in children with premature birth.

    Science.gov (United States)

    Chuthapisith, Jariya; Jantarapagdee, Kakanang; Roongpraiwan, Rawiwan; Nunnarumit, Pracha

    2014-07-01

    Children born preterm are at increased risk for executive dysfunction, which affects learning outcomes. Picture sequencing ability is considered as executive function (EF) that requires skills in working memory and organizing the pictures. Children born preterm might have difficulties in these skills. The present study aimed to develop practical Picture Sequencing test (PS test) and examine the sequencing ability in preterm children comparing with term children. The PS test was developed to assess the child's ability to arrange pictures into a sequence. It consisted of three conditions, which were daily activities, social interaction routines, and feeling expressions. Each story had four cartoon styles cards. The child had to rearrange picture cards into the correct sequence positions. Thirty preterm children aged five to six years with gestational ages of 32 weeks and birth weights of < 1,500 grams, and thirty-five term children matched age, gender child 's education, parental education, and socioeconomic status were performed the PS test. The total scores were compared between the preterm group and the term group. The PS test scores on the daily activities domain of the preterm and term group were 18 and 25 (p = 0.03), respectively. The scores on the social interaction routines domain ofthe preterm and term group were 20 and 28 (p = 0.01) and the scores on the feeling expression domain were 18.5 and25 (p = 0.03), respectively. There was no significant correlation between perinatal complications and the PS test scores. The preterm children with IQs in the average range showed impairment in sequencing ability compared with the term children. The results underline the need for follow-up care with more comprehensive assessment of EF.

  8. Picturing perturbative parton cascades in QCD matter

    Directory of Open Access Journals (Sweden)

    Aleksi Kurkela

    2015-01-01

    Full Text Available Based on parametric reasoning, we provide a simple dynamical picture of how a perturbative parton cascade, in interaction with a QCD medium, fills phase space as a function of time.

  9. Pattern Perception and Pictures for the Blind

    Directory of Open Access Journals (Sweden)

    Melissa McCarthy

    2005-01-01

    Full Text Available This article reviews recent research on perception of tangible pictures in sighted and blind people. Haptic picture naming accuracy is dependent upon familiarity and access to semantic memory, just as in visual recognition. Performance is high when haptic picture recognition tasks do not depend upon semantic memory. Viewpoint matters for the ease or difficulty of interpreting haptic pictures of solid objects. Top views were easiest for sighted and blind persons when geometrical solids had constant crosssections in the vertical axis. The presence or absence of viewpoint effects depends upon the nature of the solids that are represented. Congenitally blind people do not spontaneously produce perspective drawings, but recent data suggests that depictions including linear perspective can be understood after minimal experience. The results suggest that two-dimensional configurations are not necessarily problematic for touch.

  10. Dementia in the movies: The clinical picture

    NARCIS (Netherlands)

    Gerritsen, D.L.; Kuin, Y.; Nijboer, J.

    2014-01-01

    Objectives: Visual media influence the general public's perceptions and attitudes regarding people with mental conditions. This qualitative study investigates the depiction accuracy of dementia's clinical features in motion pictures.Method: Using the search terms 'dementia', 'Alzheimer's disease' an

  11. Dementia in the movies: the clinical picture

    NARCIS (Netherlands)

    Gerritsen, D.; Kuin, Y.; Nijboer, J.

    2014-01-01

    Objectives: Visual media influence the general public's perceptions and attitudes regarding people with mental conditions. This qualitative study investigates the depiction accuracy of dementia's clinical features in motion pictures.Method: Using the search terms dementia', Alzheimer's disease' and

  12. NIH Abroad: Pictures Are Crowd Pullers

    Science.gov (United States)

    ... Pictures Are Crowd Pullers …" Art, culture, and the Internet combine to intervene against malaria in Uganda NLM's ... Services Division collaborated on the project through the Internet. "We wanted to see if such a 'health ...

  13. Lambliasis in Children. Epidemiology, Clinical Picture, Diagnosis

    Directory of Open Access Journals (Sweden)

    A.A. Konyushevskaya

    2014-05-01

    Full Text Available The article considers the lambliasis — one of most common protozoan diseases in children. This article gives a review of literature on epidemiology, clinical picture and diagnosis of lambliasis in children as well as own observations.

  14. Descriptive complexity for pictures languages (extended abstract)

    CERN Document Server

    Grandjean, Etienne; richard, Gaétan

    2012-01-01

    This paper deals with descriptive complexity of picture languages of any dimension by syntactical fragments of existential second-order logic. - We uniformly generalize to any dimension the characterization by Giammarresi et al. \\cite{GRST96} of the class of \\emph{recognizable} picture languages in existential monadic second-order logic. - We state several logical characterizations of the class of picture languages recognized in linear time on nondeterministic cellular automata of any dimension. They are the first machine-independent characterizations of complexity classes of cellular automata. Our characterizations are essentially deduced from normalization results we prove for first-order and existential second-order logics over pictures. They are obtained in a general and uniform framework that allows to extend them to other "regular" structures. Finally, we describe some hierarchy results that show the optimality of our logical characterizations and delineate their limits.

  15. Optimization of conditions for supercritical fluid extraction of flavonoids from hops (Humulus lupulus L.)

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Waste hops are good sources offlavonoids. Extraction offlavonoids from waste hops (SC-CO2 extracted hops) using supercritical fluids technology was investigated. Various temperatures, pressures and concentrations of ethanol (modifier) and the ratio (w/w) of solvent to material were tested in this study. The results of single factor and orthogonal experiments showed that at 50℃, 25 MPa, the ratio of solvent to material (50%), ethanol concentration (80%) resulted in maximum extraction yield flavonoids (7.8 mg/g). HPLC-MS analysis of the extracts indicated that flavonoids obtained were xanthohumol, the principal prenylflavonoid in hops.

  16. Antifeedant activity of xanthohumol and supercritical carbon dioxide extract of spent hops against stored product pests.

    Science.gov (United States)

    Jackowski, J; Hurej, M; Rój, E; Popłoński, J; Kośny, L; Huszcza, E

    2015-08-01

    Xanthohumol, a prenylated flavonoid from hops, and a supercritical carbon dioxide extract of spent hops were studied for their antifeedant activity against stored product insect pests: Sitophilus granarius L., Tribolium confusum Duv. and Trogoderma granarium Everts. Xanthohumol exhibited medium deterrent activity against the adults of S. granarius L. and larvae of T. confusum Duv. The spent hops extract was more active than xanthohumol towards the adults of T. confusum Duv. The potential application of the crude spent hops extract as a feeding deterrent against the stored product pests is proposed.

  17. Hip-hop as a resource for understanding the urban context

    Science.gov (United States)

    Brown, Bryan

    2010-06-01

    This review explores Edmin's "Science education for the hip-hop generation" by documenting how he frames hip-hop as a means to access urban student culture. He argues that hip-hop is more than a mere music genre, but rather a culture that provides young people with ways of connecting to the world. Two primary ideas emerged as central to his work. First, he contends that students develop communal relationships and collective identities based on the common experiences expressed in hip-hop. Second, he identifies how the conscious recognition of institutional oppression serves a central feature in urban schools. Emdin's rich, and personal call for a greater understanding of hip-hop culture provides the text with an unmatched strength. He skillfully uses personal narratives from his own experience as well as quotes and references from hip-hop songs to make the nuances of hip hop transparent to science educators. Conversely, the limitation of this text is found in its unfulfilled promise to provide pragmatic examples of how to engage in a hip-hop based science education. Emdin's work is ultimately valuable as it extends our current knowledge about urban students and hip-hop in meaningful ways.

  18. Hops in Virginia: Need-to-Know Information about the Industry

    OpenAIRE

    Siegle, Laura

    2016-01-01

    Provides information and background concerning the growing of hops in Virginia, including production, management, new grower considerations, harvest, marketing, and the development of the industry in the state.

  19. Two Comments on Predictive Picture Coding

    Institute of Scientific and Technical Information of China (English)

    1998-01-01

    Two comments on predictive picture coding are given in this paper. 1) In lossy coding, the reconstructed values of picture samples, not its original values, should be used in the prediction formula. 2) In the design of optimum predictors, the minimum entropy or subjective assessment or other criterions, could be used, depending on the applications of the prediction encoder, instead of the minimum mean square error (MMSE) criterion.

  20. 3-Sulfanyl-4-methylpentan-1-ol in Dry-Hopped Beers: First Evidence of Glutathione S-Conjugates in Hop (Humulus lupulus L.).

    Science.gov (United States)

    Kankolongo Cibaka, Marie-Lucie; Decourrière, Laura; Lorenzo-Alonso, Celso-José; Bodart, Etienne; Robiette, Raphaël; Collin, Sonia

    2016-11-16

    Monovarietal dry-hopped beers were produced with the dual-purpose hop cultivars Amarillo, Hallertau Blanc, and Mosaic. The grapefruit-like 3-sulfanyl-4-methylpentan-1-ol was found in all three beers at concentrations much higher than expected on the basis of the free thiol content in hop. Even cysteinylated precursors proved unable to explain our results. As observed in wine, the occurrence of S-glutathione precursors was therefore suspected in hop. The analytical standards of S-3-(4-methyl-1-hydroxypentyl)glutathione, never described before, and of S-3-(1-hydroxyhexyl)glutathione, previously evidenced in grapes, were chemically synthesized. An optimized extraction of glutathionylated precursors was then applied to Amarillo, Hallertau Blanc, and Mosaic hop samples. HPLC-ESI(+)MS/MS revealed, for the first time, the occurrence of S-3-(1-hydroxyhexyl)glutathione and S-3-(4-methyl-1-hydroxypentyl)glutathione in hop, at levels well above those reported for their cysteinylated counterparts. S-3-(1-Hydroxyhexyl)glutathione emerged in all cases as the major adduct in hop. Yet, although 3-sulfanylhexan-1-ol seems relatively ubiquitous in free, cysteinylated, and glutathionylated forms, the glutathione adduct of 3-sulfanyl-4-methylpentan-1-ol, never evidenced in other plants up to now, was found only in the Hallertau Blanc variety.

  1. Fundamentals and health benefits of xanthohumol, a natural product derived from hops and beer.

    Science.gov (United States)

    Magalhães, Paulo J; Carvalho, Daniel O; Cruz, José M; Guido, Luís F; Barros, Aquiles A

    2009-05-01

    In recent years, there has been a growing interest in phenolic compounds and their presumed role in the prevention of various degenerative diseases, such as cancer and cardiovascular diseases. Xanthohumol, a prenylated chalcone from hops and beer, is among the phenolic compounds which have received the most attention in recent years. This compound has a range of interesting biological properties that may have therapeutic utility. Based on the health-promoting properties of xanthohumol, the production of a beer enriched in this substance would be of huge interest to the brewing industry, for the benefits this could bring to consumer's health. This paper reviews recent and important data with respect to the health benefits or biological activities of xanthohumol and beer. In addition, an overview of the chemistry and biotechnological aspects of xanthohumol is presented.

  2. Crossmodal interactions during affective picture processing.

    Directory of Open Access Journals (Sweden)

    Vera Ferrari

    Full Text Available "Natural" crossmodal correspondences, such as the spontaneous tendency to associate high pitches with high spatial locations, are often hypothesized to occur preattentively and independently of task instructions (top-down attention. Here, we investigate bottom-up attentional engagement by using emotional scenes that are known to naturally and reflexively engage attentional resources. We presented emotional (pleasant and unpleasant or neutral pictures either below or above a fixation cross, while participants were required to discriminate between a high or a low pitch tone (experiment 1. Results showed that despite a robust crossmodal attentional capture of task-irrelevant emotional pictures, the general advantage in classifying the tones for congruent over incongruent visual-auditory stimuli was similar for emotional and neutral pictures. On the other hand, when picture position was task-relevant (experiment 2, task-irrelevant tones did not interact with pictures with regard to their combination of pitch and visual vertical spatial position, but instead they were effective in minimizing the interference effect of emotional picture processing on the ongoing task. These results provide constraints on our current understanding of natural crossmodal correspondences.

  3. Sensomics analysis of key bitter compounds in the hard resin of hops (Humulus lupulus L.) and their contribution to the bitter profile of Pilsner-type beer.

    Science.gov (United States)

    Dresel, Michael; Dunkel, Andreas; Hofmann, Thomas

    2015-04-08

    Recent brewing trials indicated the occurrence of valuable bitter compounds in the hard resin fraction of hop. Aiming at the discovery of these compounds, hop's ε-resin was separated by means of a sensory guided fractionation approach and the key taste molecules were identified by means of UV/vis, LC-TOF-MS, and 1D/2D-NMR studies as well as synthetic experiments. Besides a series of literature known xanthohumol derivatives, multifidol glucosides, flavon-3-on glycosides, and p-coumaric acid esters, a total of 11 bitter tastants are reported for the first time, namely, 1",2"-dihydroxanthohumol F, 4'-hydroxytunicatachalcone, isoxantholupon, 1-methoxy-4-prenylphloroglucinol, dihydrocyclohumulohydrochinone, xanthohumols M, N, and P, and isoxanthohumols M, N, and P, respectively. Human sensory analysis revealed low bitter recognition threshold concentrations ranging from 5 (co-multifidol glucopyranoside) to 198 μmol/L (trans-p-coumaric acid ethyl ester) depending on their chemical structure. For the first time, LC-MS/MS quantitation of these taste compounds in Pilsner-type beer, followed by taste re-engineering experiments, revealed the additive contribution of iso-α-acids and the identified hard resin components to be truly necessary and sufficient for constructing the authentic bitter percept of beer. Finally, brewing trails using the ε-resin as the only hop source impressively demonstrated the possibility to produce beverages strongly enriched with prenylated hop flavonoids.

  4. Digital Picture Production and Picture aesthetic Competency in It-didactic Design

    DEFF Research Database (Denmark)

    Rasmussen, Helle

    In my presentation at the InSEA Conference 2015 I want to introduce my ongoing Ph.D. project with the title ‘Digital Picture Production and Picture aesthetic Competency in It-didactic Design’. The objective of the project is to provide a basis for upgrading and renewal of lessons in the school...... subject Visual Arts – and crosswise of subjects in school. The overall research question has been: How can IT-didactic designs support lessons in production of complex meaning in digital pictures and increase the development of pupil’s picture aesthetic competences? By using the expression ‘complex...... potential in digital picture productions will tend to be distinctly complex, such as also Mie Buhl has pointed with reference to Paul Duncum. (Buhl 2005, Duncum 2014). To handle production of such distinctly complex meaning in digital pictures seems to be a didactic challenge in school. It also seems like...

  5. Hopping in a supercooled binary Lennard-Jones liquid

    DEFF Research Database (Denmark)

    Schrøder, Thomas; Dyre, Jeppe

    1998-01-01

    A binary Lennard–Jones liquid has been investigated by molecular dynamics at equilibrium supercooled conditions. At the lowest temperature investigated, hopping is present in the system as indicated by a secondary peak in 4r2Gs(r,t), where Gs(r,t) is the van Hove self correlation function....... To examine the dynamics of the system, we consider transitions between the inherent structures (local minima in the potential energy) along the trajectory. We conclude that the plateau in the mean square displacement found at lower temperatures is indeed a result of particles being trapped in local "cages...

  6. Lejos de NYC: El hip-hop en Chile

    OpenAIRE

    Rainer Quitzow

    2005-01-01

    En este artículo se abordan las manifestaciones concretas de una forma cultural urbana exportada desde Occidente a los países en desarrollo. A través de una reconstrucción de la historia de la cultura hip hop en Chile, se han intendado esbozar algunas conclusiones sobre su influencia en la formación de una identidad cultural urbana, tratando además de relacionar el desarrollo histórico del movimiento y de las prácticas actuales de la juventud en Santiago con tendencias más amplias en la socie...

  7. Novel Frequency Hopping Sequences Generator Based on AES Algorithm

    Institute of Scientific and Technical Information of China (English)

    李振荣; 庄奕琪; 张博; 张超

    2010-01-01

    A novel frequency hopping(FH) sequences generator based on advanced encryption standard(AES) iterated block cipher is proposed for FH communication systems.The analysis shows that the FH sequences based on AES algorithm have good performance in uniformity, correlation, complexity and security.A high-speed, low-power and low-cost ASIC of FH sequences generator is implemented by optimizing the structure of S-Box and MixColumns of AES algorithm, proposing a hierarchical power management strategy, and applying ...

  8. Totally asymmetric exclusion processes with spatially periodic hopping rates

    Science.gov (United States)

    Lakatos, Greg; Kolomeisky, Anatoly; Chou, Tom

    2004-03-01

    Using mean-field and numerical methods, we analyze the steady-state behavior of totally asymmetric simple exclusion processes (TASEPs) containing periodically varying movement rates. In our models particles at a majority sites hop to the right with rate p_1, while particles occupying a periodically arranged set of sites move to the right at rate p_2. While exact solutions for the steady-state particle currents and densities are not found, the mean field results show good agreement with data derived from extensive Monte-Carlo simulations.

  9. Semiclassical quantization of nonadiabatic systems with hopping periodic orbits

    Energy Technology Data Exchange (ETDEWEB)

    Fujii, Mikiya, E-mail: mikiya.fujii@gmail.com; Yamashita, Koichi [Department of Chemical System Engineering, School of Engineering, The University of Tokyo, Tokyo 113-8656 (Japan); JST, CREST, Tokyo 113-8656 (Japan)

    2015-02-21

    We present a semiclassical quantization condition, i.e., quantum–classical correspondence, for steady states of nonadiabatic systems consisting of fast and slow degrees of freedom (DOFs) by extending Gutzwiller’s trace formula to a nonadiabatic form. The quantum–classical correspondence indicates that a set of primitive hopping periodic orbits, which are invariant under time evolution in the phase space of the slow DOF, should be quantized. The semiclassical quantization is then applied to a simple nonadiabatic model and accurately reproduces exact quantum energy levels. In addition to the semiclassical quantization condition, we also discuss chaotic dynamics involved in the classical limit of nonadiabatic dynamics.

  10. Semiclassical quantization of nonadiabatic systems with hopping periodic orbits

    Science.gov (United States)

    Fujii, Mikiya; Yamashita, Koichi

    2015-02-01

    We present a semiclassical quantization condition, i.e., quantum-classical correspondence, for steady states of nonadiabatic systems consisting of fast and slow degrees of freedom (DOFs) by extending Gutzwiller's trace formula to a nonadiabatic form. The quantum-classical correspondence indicates that a set of primitive hopping periodic orbits, which are invariant under time evolution in the phase space of the slow DOF, should be quantized. The semiclassical quantization is then applied to a simple nonadiabatic model and accurately reproduces exact quantum energy levels. In addition to the semiclassical quantization condition, we also discuss chaotic dynamics involved in the classical limit of nonadiabatic dynamics.

  11. Lejos de NYC: El hip-hop en Chile

    OpenAIRE

    Rainer Quitzow

    2005-01-01

    En este artículo se abordan las manifestaciones concretas de una forma cultural urbana exportada desde Occidente a los países en desarrollo. A través de una reconstrucción de la historia de la cultura hip hop en Chile, se han intendado esbozar algunas conclusiones sobre su influencia en la formación de una identidad cultural urbana, tratando además de relacionar el desarrollo histórico del movimiento y de las prácticas actuales de la juventud en Santiago con tendencias más amplias en la socie...

  12. Olhares figurados, figuras do olhar: fotografia e movimento Hip Hop

    OpenAIRE

    Rodrigues, Juliana de Oliveira

    2006-01-01

    O presente estudo toma por objeto as fotografias realizadas por integrantes do Movimento Hip Hop, da cidade de São Carlos (SP), nas quais constroem um olhar sobre si mesmo pelas experiências da vida em grupo. Centrada nos procedimentos de figurativização e tematização, esta pesquisa preocupa-se com as diversas figuras enredadas pelo conjunto fotográfico, que implicam em estratégias discursivas capazes de tornar visível os diferentes modos de o grupo se mostrar no mundo. Em decorrência disso, ...

  13. Consideration of vision and picture quality: psychological effects induced by picture sharpness

    Science.gov (United States)

    Kusaka, Hideo

    1989-08-01

    A psychological hierarchy model of human vision(1)(2) suggests that the visual signals are processed in a serial manner from lower to higher stages: that is "sensation" - "perception" - "emotion." For designing a future television system, it is important to find out what kinds of physical factors affect the "emotion" experienced by an observer in front of the display. This paper describes the psychological effects induced by the sharpness of the picture. The subjective picture quality was evaluated for the same pictures with five different levels of sharpness. The experiment was performed on two kinds of printed pictures: (A) a woman's face, and (B) a town corner. From these experiments, it was found that the amount of high-frequency peaking (physical value of the sharpness) which psychologically gives the best picture quality, differs between pictures (A) and (B). That is, the optimum picture sharpness differs depending on the picture content. From these results, we have concluded that the psychophysical sharpness of the picture is not only determined at the stage of "perception" (e.g., resolution or signal to noise ratio, which everyone can judge immediately), but also at the stage of "emotion" (e.g., sensation of reality or beauty).

  14. High-Speed On-Board Data Processing for Science Instruments: HOPS

    Science.gov (United States)

    Beyon, Jeffrey

    2015-01-01

    The project called High-Speed On-Board Data Processing for Science Instruments (HOPS) has been funded by NASA Earth Science Technology Office (ESTO) Advanced Information Systems Technology (AIST) program during April, 2012 â€" April, 2015. HOPS is an enabler for science missions with extremely high data processing rates. In this three-year effort of HOPS, Active Sensing of CO2 Emissions over Nights, Days, and Seasons (ASCENDS) and 3-D Winds were of interest in particular. As for ASCENDS, HOPS replaces time domain data processing with frequency domain processing while making the real-time on-board data processing possible. As for 3-D Winds, HOPS offers real-time high-resolution wind profiling with 4,096-point fast Fourier transform (FFT). HOPS is adaptable with quick turn-around time. Since HOPS offers reusable user-friendly computational elements, its FPGA IP Core can be modified for a shorter development period if the algorithm changes. The FPGA and memory bandwidth of HOPS is 20 GB/sec while the typical maximum processor-to-SDRAM bandwidth of the commercial radiation tolerant high-end processors is about 130-150 MB/sec. The inter-board communication bandwidth of HOPS is 4 GB/sec while the effective processor-to-cPCI bandwidth of commercial radiation tolerant high-end boards is about 50-75 MB/sec. Also, HOPS offers VHDL cores for the easy and efficient implementation of ASCENDS and 3-D Winds, and other similar algorithms. A general overview of the 3-year development of HOPS is the goal of this presentation.

  15. Different Loci of Semantic Interference in Picture Naming vs. Word-Picture Matching Tasks.

    Science.gov (United States)

    Harvey, Denise Y; Schnur, Tatiana T

    2016-01-01

    Naming pictures and matching words to pictures belonging to the same semantic category impairs performance relative to when stimuli come from different semantic categories (i.e., semantic interference). Despite similar semantic interference phenomena in both picture naming and word-picture matching tasks, the locus of interference has been attributed to different levels of the language system - lexical in naming and semantic in word-picture matching. Although both tasks involve access to shared semantic representations, the extent to which interference originates and/or has its locus at a shared level remains unclear, as these effects are often investigated in isolation. We manipulated semantic context in cyclical picture naming and word-picture matching tasks, and tested whether factors tapping semantic-level (generalization of interference to novel category items) and lexical-level processes (interactions with lexical frequency) affected the magnitude of interference, while also assessing whether interference occurs at a shared processing level(s) (transfer of interference across tasks). We found that semantic interference in naming was sensitive to both semantic- and lexical-level processes (i.e., larger interference for novel vs. old and low- vs. high-frequency stimuli), consistent with a semantically mediated lexical locus. Interference in word-picture matching exhibited stable interference for old and novel stimuli and did not interact with lexical frequency. Further, interference transferred from word-picture matching to naming. Together, these experiments provide evidence to suggest that semantic interference in both tasks originates at a shared processing stage (presumably at the semantic level), but that it exerts its effect at different loci when naming pictures vs. matching words to pictures.

  16. A carrier hopping mechanism for bipolar field induced resistive switching in metal electrode-praseodymium calcium manganese trioxide interfaces

    Science.gov (United States)

    Tsui, Stephen Alan

    Bipolar resistive switching in metal electrode-Pr0.7Ca 0.3MnO3 (PCMO) configurations as a result of the application of a voltage pulse has stirred a great deal of interest and debate in recent years. The overwhelming significance of such a phenomenon would be its potential application as a nonvolatile memory device, especially in light of demand for ever diminishing sizes for device architecture. However, the uncertainty over the underlying physical mechanism poses a great obstacle in predicting the industrial viability of the PCMO switch. This dissertation will address several of the key controversial issues and develop a self consistent physical picture for the resistive switching. In our work, we have identified the switching to be restricted to the interface region between the PCMO and the deposited metal electrode, in contrast to early claims of a bulk phenomenon. The interfacial nature of the switch is further confirmed by the observation of switching in other metal-perovskite oxide interfaces, thereby removing any restriction to PCMO for device consideration. Electronic transport measurements on our samples reveal that the conduction at the interface can be fitted by a percolative framework dominated by a bottleneck section. The associated conduction process is likely to be carrier hopping, and the electric field dependence data show that the switching indeed originates from a reversible change in the number of available interfacial hopping sites between the high and low resistance states. The key, therefore, to realizing a device lies in controlling the formation and behavior of the bottleneck. Although the exact identity and nature of these structures remain under investigation, the data are promising in that a nm-scale nonvolatile memory device may be achievable.

  17. Lejos de NYC: El hip-hop en Chile

    Directory of Open Access Journals (Sweden)

    Rainer Quitzow

    2005-03-01

    Full Text Available En este artículo se abordan las manifestaciones concretas de una forma cultural urbana exportada desde Occidente a los países en desarrollo. A través de una reconstrucción de la historia de la cultura hip hop en Chile, se han intendado esbozar algunas conclusiones sobre su influencia en la formación de una identidad cultural urbana, tratando además de relacionar el desarrollo histórico del movimiento y de las prácticas actuales de la juventud en Santiago con tendencias más amplias en la sociedad chilena. En particular, se ha intentado determinar si el hip hop proporciona un formato significativo para la expresión de los problemas de los jóvenes urbanos de Chile, o si es parte de lo que algunos autores denominan una “pérdida cultural”, como consecuencia del capitalismo global y el imperialismo cultural de Estados Unidos.

  18. HOPS 383: AN OUTBURSTING CLASS 0 PROTOSTAR IN ORION

    Energy Technology Data Exchange (ETDEWEB)

    Safron, Emily J.; Megeath, S. Thomas; Booker, Joseph [Ritter Astrophysical Observatory, Department of Physics and Astronomy, University of Toledo, Toledo, OH (United States); Fischer, William J. [NASA Goddard Space Flight Center, Greenbelt, MD (United States); Furlan, Elise; Rebull, Luisa M. [Infrared Processing and Analysis Center, Caltech, Pasadena, CA (United States); Stutz, Amelia M. [Max-Planck-Institut für Astronomie, Heidelberg (Germany); Stanke, Thomas [European Southern Observatory, Garching bei München (Germany); Billot, Nicolas [Instituto de Radio Astronomía Milimétrica, Granada (Spain); Tobin, John J. [Leiden Observatory, Leiden (Netherlands); Ali, Babar [Space Science Institute, Boulder, CO (United States); Allen, Lori E. [National Optical Astronomy Observatory, Tucson, AZ (United States); Watson, Dan M. [Department of Physics and Astronomy, University of Rochester, Rochester, NY (United States); Wilson, T. L., E-mail: wjfischer@gmail.com [Naval Research Laboratory, Washington, DC (United States)

    2015-02-10

    We report the dramatic mid-infrared brightening between 2004 and 2006 of Herschel Orion Protostar Survey (HOPS) 383, a deeply embedded protostar adjacent to NGC 1977 in Orion. By 2008, the source became a factor of 35 brighter at 24 μm with a brightness increase also apparent at 4.5 μm. The outburst is also detected in the submillimeter by comparing APEX/SABOCA to SCUBA data, and a scattered-light nebula appeared in NEWFIRM K{sub s} imaging. The post-outburst spectral energy distribution indicates a Class 0 source with a dense envelope and a luminosity between 6 and 14 L{sub ⊙}. Post-outburst time-series mid- and far-infrared photometry show no long-term fading and variability at the 18% level between 2009 and 2012. HOPS 383 is the first outbursting Class 0 object discovered, pointing to the importance of episodic accretion at early stages in the star formation process. Its dramatic rise and lack of fading over a 6 year period hint that it may be similar to FU Ori outbursts, although the luminosity appears to be significantly smaller than the canonical luminosities of such objects.

  19. Hops for Menopausal Vasomotor Symptoms: Mechanisms of Action

    Science.gov (United States)

    Abdi, Fatemeh; Mobedi, Hamid

    2016-01-01

    Menopause is a critical stage of women's life associated with various complaints and distresses. Vasomotor symptoms (VMS), such as hot flushes, night sweats, sleep disturbances, and fatigue, are the most common menopause symptoms affecting about 50% to 80% of middle-aged women. Obviously, these symptoms, resulting from estrogen deficiency during menopause, can exert negative effects on women's health and quality of life and thus require to be managed through approaches such as hormone replacement therapy (HRT). Many herbal treatments for menopause symptoms contain and its components such as 8-prenylnaringenin, 6-PN, isoxanthohumol and xanthohumol. Recent in-vivo studies have highlighted the ability of 8-prenylnaringenin to reduce serum-luteinizing hormone (LH) and follicle-stimulating hormone (FSH), to increase serum prolactin levels and uterine weight, and to induce vaginal hyperplastic epithelium. Previous research has shown that hops extract can strongly bind to both estrogen receptors, stimulate alkaline phosphatase activity in Ishikawa cells, and upregulate presenelin-2 and progesterone receptor mRNA in Ishikawa cells. Numerous clinical trials have documented significant reductions in the frequency of hot flushes following the administration of hop-containing preparations. Nevertheless, further clinical trials with larger sample size and longer follow-up are warranted to confirm such benefits. PMID:27617238

  20. Thermopower of molecular junctions: Tunneling to hopping crossover in DNA

    Science.gov (United States)

    Korol, Roman; Kilgour, Michael; Segal, Dvira

    2016-12-01

    We study the electrical conductance G and the thermopower S of single-molecule junctions and reveal signatures of different transport mechanisms: off-resonant tunneling, on-resonant coherent (ballistic) motion, and multi-step hopping. These mechanisms are identified by studying the behavior of G and S while varying molecular length and temperature. Based on a simple one-dimensional model for molecular junctions, we derive approximate expressions for the thermopower in these different regimes. Analytical results are compared to numerical simulations, performed using a variant of Büttiker's probe technique, the so-called voltage-temperature probe, which allows us to phenomenologically introduce environmentally induced elastic and inelastic electron scattering effects, while applying both voltage and temperature biases across the junction. We further simulate the thermopower of GC-rich DNA sequences with mediating A:T blocks and manifest the tunneling-to-hopping crossover in both the electrical conductance and the thermopower, in accord with measurements by Li et al. [Nat. Commun. 7, 11294 (2016)].

  1. CPG Control for Biped Hopping Robot in Unpredictable Environment

    Institute of Scientific and Technical Information of China (English)

    Tingting Wang; Wei Guo; Mantian Li; Fusheng Zha; Lining Sun

    2012-01-01

    A CPG control mechanism is proposed for hopping motion control of biped robot in unpredictable environment.Based on analysis of robot motion and biological observation of animal's control mechanism,the motion control task is divided into two simple parts:motion sequence control and output force control.Inspired by a two-level CPG model,a two-level CPG control mechanism is constructed to coordinate the drivers of robot joint,while various feedback information are introduced into the control mechanism.Interneurons within the control mechanism are modeled to generate motion rhythm and pattern promptly for motion sequence control; motoneurons are modeled to control output forces of joint drivers in real time according to feedbacks.The control system can perceive changes caused by unknown perturbations and environment changes according to feedback information,and adapt to unpredictable environment by adjusting outputs of neurons.The control mechanism is applied to a biped hopping robot in unpredictable environment on simulation platform,and stable adaptive motions are obtained.

  2. Hopping electron model with geometrical frustration: kinetic Monte Carlo simulations

    Science.gov (United States)

    Terao, Takamichi

    2016-09-01

    The hopping electron model on the Kagome lattice was investigated by kinetic Monte Carlo simulations, and the non-equilibrium nature of the system was studied. We have numerically confirmed that aging phenomena are present in the autocorrelation function C ({t,tW )} of the electron system on the Kagome lattice, which is a geometrically frustrated lattice without any disorder. The waiting-time distributions p(τ ) of hopping electrons of the system on Kagome lattice has been also studied. It is confirmed that the profile of p (τ ) obtained at lower temperatures obeys the power-law behavior, which is a characteristic feature of continuous time random walk of electrons. These features were also compared with the characteristics of the Coulomb glass model, used as a model of disordered thin films and doped semiconductors. This work represents an advance in the understanding of the dynamics of geometrically frustrated systems and will serve as a basis for further studies of these physical systems.

  3. A decentralized scheduling algorithm for time synchronized channel hopping

    Directory of Open Access Journals (Sweden)

    Andrew Tinka

    2011-09-01

    Full Text Available Time Synchronized Channel Hopping (TSCH is an existing Medium Access Control scheme which enables robust communication through channel hopping and high data rates through synchronization. It is based on a time-slotted architecture, and its correct functioning depends on a schedule which is typically computed by a central node. This paper presents, to our knowledge, the first scheduling algorithm for TSCH networks which both is distributed and which copes with mobile nodes. Two variations on scheduling algorithms are presented. Aloha-based scheduling allocates one channel for broadcasting advertisements for new neighbors. Reservation- based scheduling augments Aloha-based scheduling with a dedicated timeslot for targeted advertisements based on gossip information. A mobile ad hoc motorized sensor network with frequent connectivity changes is studied, and the performance of the two proposed algorithms is assessed. This performance analysis uses both simulation results and the results of a field deployment of floating wireless sensors in an estuarial canal environment. Reservation-based scheduling performs significantly better than Aloha-based scheduling, suggesting that the improved network reactivity is worth the increased algorithmic complexity and resource consumption.

  4. Effective Capacity of Two-Hop Wireless Communication Systems

    CERN Document Server

    Qiao, Deli; Velipasalar, Senem

    2011-01-01

    A two-hop wireless communication link in which a source sends data to a destination with the aid of an intermediate relay node is studied. It is assumed that there is no direct link between the source and the destination, and the relay forwards the information to the destination by employing the decode-and-forward scheme. Both the source and intermediate relay nodes are assumed to operate under statistical quality of service (QoS) constraints imposed as limitations on the buffer overflow probabilities. The maximum constant arrival rates that can be supported by this two-hop link in the presence of QoS constraints are characterized by determining the effective capacity of such links as a function of the QoS parameters and signal-to-noise ratios at the source and relay, and the fading distributions of the links. The analysis is performed for both full-duplex and half-duplex relaying. Through this study, the impact upon the throughput of having buffer constraints at the source and intermediate relay nodes is ide...

  5. Spin-Dependent Hopping Transport in Magnetic Perovskites

    Science.gov (United States)

    Bruynseraede, Y.; Wagner, P.; Gordon, I.; Trappeniers, L.; Herlach, F.; Moshchalkov, V.

    1998-03-01

    Epitaxial films of Nd_0.5Sr_0.5MnO3 show a transition from paramagnetic-semiconducting to ferromagnetic-quasimetallic behavior at TC = 207 K and a colossal negative magnetoresistivity (CMR) of 750 % at 150 K, 12 T. Hall effect studies indicate a slightly increasing carrier density at the para- to ferromagnetic transition from 0.3 to 0.5 holes per unit cell. External magnetic fields do not affect these densities and the CMR effect is therefore caused by a field-induced enhancement of carrier mobility. The mobility gain can be described by a Mott-type model in which the hopping barrier is extended by a term related to the mutual spin orientation at neighbouring hopping sites, i. e. Mn ions of different valency. This model predicts a scaling behaviour of the CMR effect at constant temperature proportional to the Brillouin function \\cal B in the ferromagnetic state, and to \\cal B^2 for the paramagnet. Both results are confirmed by CMR measurements in pulsed magnetic fields up to 50 T.

  6. Contributions to the quality control of two crops of economic importance : hops and yerba mate

    NARCIS (Netherlands)

    Wilson, Erica Georgina

    2012-01-01

    Quality control of plants is essential and at the same time very challenging.In this thesis, studies involving quality issues of two plants used in the production of two popular beverages, hops (in beer) and Ilex paraguariensis (yerba mate) were undertaken. Hops are used as bittering agents and to

  7. Characterisation of the Plasmodium falciparum Hsp70-Hsp90 organising protein (PfHop).

    Science.gov (United States)

    Gitau, Grace W; Mandal, Pradipta; Blatch, Gregory L; Przyborski, Jude; Shonhai, Addmore

    2012-03-01

    Malaria is caused by Plasmodium species, whose transmission to vertebrate hosts is facilitated by mosquito vectors. The transition from the cold blooded mosquito vector to the host represents physiological stress to the parasite, and additionally malaria blood stage infection is characterised by intense fever periods. In recent years, it has become clear that heat shock proteins play an essential role during the parasite's life cycle. Plasmodium falciparum expresses two prominent heat shock proteins: heat shock protein 70 (PfHsp70) and heat shock protein 90 (PfHsp90). Both of these proteins have been implicated in the development and pathogenesis of malaria. In eukaryotes, Hsp70 and Hsp90 proteins are functionally linked by an essential adaptor protein known as the Hsp70-Hsp90 organising protein (Hop). In this study, recombinant P. falciparum Hop (PfHop) was heterologously produced in E. coli and purified by nickel affinity chromatography. Using specific anti-PfHop antisera, the expression and localisation of PfHop in P. falciparum was investigated. PfHop was shown to co-localise with PfHsp70 and PfHsp90 in parasites at the trophozoite stage. Gel filtration and co-immunoprecipitation experiments suggested that PfHop was present in a complex together with PfHsp70 and PfHsp90. The association of PfHop with both PfHsp70 and PfHsp90 suggests that this protein may mediate the functional interaction between the two chaperones.

  8. Contributions to the quality control of two crops of economic importance : hops and yerba mate

    NARCIS (Netherlands)

    Wilson, Erica Georgina

    2012-01-01

    Quality control of plants is essential and at the same time very challenging.In this thesis, studies involving quality issues of two plants used in the production of two popular beverages, hops (in beer) and Ilex paraguariensis (yerba mate) were undertaken. Hops are used as bittering agents and to

  9. Topological phase transitions driven by next-nearest-neighbor hopping in two-dimensional lattices

    NARCIS (Netherlands)

    Beugeling, W.; Everts, J.C.; de Morais Smith, C.

    2012-01-01

    For two-dimensional lattices in a tight-binding description, the intrinsic spin-orbit coupling, acting as a complex next-nearest-neighbor hopping, opens gaps that exhibit the quantum spin Hall effect. In this paper, we study the effect of a real next-nearest-neighbor hopping term on the band structu

  10. Polish Hip Hop as a Form of Multiliteracies and Situated Learning

    Science.gov (United States)

    Torrence, Michael L.

    2009-01-01

    The purpose of this ethnographic study was to examine Hip Hop in Poland through the lens of multiliteracies and situated learning. This analysis is concerned with the transmission of Hip Hop to and within Wroclaw, Poland, and its acculturation and assimilation in Wroclaw, Poland. Further, this study seeks to illustrate how professional Polish Hip…

  11. Hip-Hop and a Hybrid Text in a Postsecondary English Class

    Science.gov (United States)

    Sanchez, Deborah M.

    2010-01-01

    This study explores the epistemology present in hip-hop music and its reflection in the writing of one African American student in a postsecondary transitional English class. An integration of hip-hop and academic literacy practices in the student's essay challenges the supremacy of a "standard" academic English and deficit perspectives about…

  12. Evaluating the Impact of Transmission Power on Selecting Tall Vehicles as Best Next Communication Hop

    NARCIS (Netherlands)

    Qiao, Yu; Klein Wolterink, Wouter; Karagiannis, Georgios; Heijenk, Geert

    2012-01-01

    The relatively low height of antennas on communicating vehicles in Vehicular Ad Hoc Networks (VANETs) makes one hop and as well multi-hop Vehicle-to-Vehicle (V2V) communication susceptible to obstruction by other vehicles on the road. When the transmitter or receiver (or both) is a Tall vehi- cle, (

  13. Connectivity model for Inter-working multi-hop wireless networks

    CSIR Research Space (South Africa)

    Salami, O

    2009-08-01

    Full Text Available pairs in inter-working multi-hop wireless networks can be evaluated based on the availability of radio links and communication routes. This paper presents an analytical study of the link and route availability in inter-working multi-hop wireless networks....

  14. Sampling Practices and Social Spaces: Exploring a Hip-Hop Approach to Higher Education

    Science.gov (United States)

    Petchauer, Emery

    2010-01-01

    Much more than a musical genre, hip-hop culture exists as an animating force in the lives of many young adults. This article looks beyond the moral concerns often associated with rap music to explore how hip-hop as a larger set of expressions and practices implicates the educational experiences, activities, and approaches for students. The article…

  15. Affiliation and Alienation: Hip-Hop, Rap, and Urban Science Education

    Science.gov (United States)

    Emdin, Christopher

    2010-01-01

    The critiques of rap artists and other participants in hip-hop culture provide data for teachers and researchers to investigate the attitudes of US urban youth towards schooling. This study explores the complex relationships between hip-hop and science education by examining how rap lyrics project beliefs about schooling, the relevance of existing…

  16. Trends in German Hip Hop Music and Its Usefulness for the Classroom

    Science.gov (United States)

    Schmidt, Johannes

    2008-01-01

    German hip hop music has proved productive, especially since 2000 when rap in Germany experienced something like a first crisis. As a response, German hip hop artists and record labels have ventured off in several different directions including other musical genres, different topics, and new approaches to German rap. This article discusses the…

  17. Empowerment in Context: Lessons from Hip-Hop Culture for Social Work Practice

    Science.gov (United States)

    Travis, Raphael, Jr.; Deepak, Anne

    2011-01-01

    Hip-hop culture can be used as a conduit to enhanced cultural competence and practice skills through the individual and community empowerment framework. This framework is introduced as a tool for direct practice that allows social workers to understand the competing messages within hip-hop culture and how they may impact youths by promoting or…

  18. Student Perceptions of the Hip Hop Culture's Influence on the Undergraduate Experience

    Science.gov (United States)

    Wessel, Roger D.; Wallaert, Kerry A.

    2011-01-01

    This study sought to determine how identification and engagement with the hip hop culture influenced the educational experiences of undergraduate students at a Midwestern, predominately White university by interviewing 11 students who self-identified as being immersed in the hip hop culture. Through a qualitative, phenomenological investigation,…

  19. Spring-like leg behaviour, musculoskeletal mechanics and control in maximum and submaximum height human hopping.

    Science.gov (United States)

    Bobbert, Maarten F; Richard Casius, L J

    2011-05-27

    The purpose of this study was to understand how humans regulate their 'leg stiffness' in hopping, and to determine whether this regulation is intended to minimize energy expenditure. 'Leg stiffness' is the slope of the relationship between ground reaction force and displacement of the centre of mass (CM). Variations in leg stiffness were achieved in six subjects by having them hop at maximum and submaximum heights at a frequency of 1.7 Hz. Kinematics, ground reaction forces and electromyograms were measured. Leg stiffness decreased with hopping height, from 350 N m(-1) kg(-1) at 26 cm to 150 N m(-1) kg(-1) at 14 cm. Subjects reduced hopping height primarily by reducing the amplitude of muscle activation. Experimental results were reproduced with a model of the musculoskeletal system comprising four body segments and nine Hill-type muscles, with muscle stimulation STIM(t) as only input. Correspondence between simulated hops and experimental hops was poor when STIM(t) was optimized to minimize mechanical energy expenditure, but good when an objective function was used that penalized jerk of CM motion, suggesting that hopping subjects are not minimizing energy expenditure. Instead, we speculated, subjects are using a simple control strategy that results in smooth movements and a decrease in leg stiffness with hopping height.

  20. New STS molecular markers for assessment of genetic diversity and DNA fingerprinting in hop (Humulus lupulus L.)

    National Research Council Canada - National Science Library

    Vrba, Lukas; Matousek, Jaroslav; Patzak, Josef

    2007-01-01

    .... We demonstrate the usefulness of these STS markers and compare them to SSRs for identifying hop genotypes and estimating genetic diversity in a collection of 68 hop cultivars from around the world...

  1. Development of a Rich Picture editor

    DEFF Research Database (Denmark)

    Valente, Andrea; Marchetti, Emanuela

    2010-01-01

    rich picture practice into software proved difficult, therefore, we decided to follow a user-centered approach: design and implement a prototype with basic functionalities, then run a usability test with a few students and professionals. The feedback collected in the test validated our hypothesis circa...... the need of software support for the authoring rich pictures, but also forced us to re-consider the design of our prototype. To gain a deeper understanding of the students' working practice, we also reviewed rich pictures from past student projects. All the information gathered through our study is guiding...... us in the design of the tool next version. At a more general level we realized that modern object-oriented development methodologies, such as agile methods, are informed by design, hence they sometimes assume design skills that programmers do not have or do not value....

  2. Cosmic Inflation from Emergent Spacetime Picture

    CERN Document Server

    Yang, Hyun Seok

    2016-01-01

    We argue that the emergent spacetime picture admits a background-independent formulation of cosmic inflation. The inflation in this picture corresponds to the dynamical emergence of spacetime while the conventional inflation is simply an (exponential) expansion of a preexisting spacetime owing to the vacuum energy carried by an inflaton field. We show that the cosmic inflation arises as a time-dependent solution of the matrix quantum mechanics describing the dynamical process of Planck energy condensate in vacuum without introducing any inflaton field as well as an {\\it ad hoc} inflation potential. Thus the emergent spacetime picture realizes a background-independent description of the inflationary universe which has a sufficiently elegant and explanatory power to defend the integrity of physics against the multiverse hypothesis.

  3. The Role of Pictures in Picture Books on Children's Cognitive Engagement with Mathematics

    Science.gov (United States)

    Elia, Iliada; van den Heuvel-Panhuizen, Marja; Georgiou, Alexia

    2010-01-01

    The present study examines the cognitive activity that is evoked in young children when they are read a picture book that is written for the purpose of teaching mathematics. The focus of this study is to explore the effects of pictures on children's spontaneous mathematical cognitive engagement. The study is based on the assumption that the…

  4. Picture or Text First? Explaining Sequence Effects When Learning with Pictures and Text

    Science.gov (United States)

    Eitel, Alexander; Scheiter, Katharina

    2015-01-01

    The present article reviews 42 studies investigating the role of sequencing of text and pictures for learning outcomes. Whereas several of the reviewed studies revealed better learning outcomes from presenting the picture before the text rather than after it, other studies demonstrated the opposite effect. Against the backdrop of theories on…

  5. The Role of Pictures in Picture Books on Children's Cognitive Engagement with Mathematics

    Science.gov (United States)

    Elia, Iliada; van den Heuvel-Panhuizen, Marja; Georgiou, Alexia

    2010-01-01

    The present study examines the cognitive activity that is evoked in young children when they are read a picture book that is written for the purpose of teaching mathematics. The focus of this study is to explore the effects of pictures on children's spontaneous mathematical cognitive engagement. The study is based on the assumption that the…

  6. Hopping magnetotransport of the band-gap tuning Cu2Zn(Sn x Ge1-x )Se4 crystals

    Science.gov (United States)

    Lähderanta, E.; Hajdeu-Chicarosh, E.; Shakhov, M. A.; Guc, M.; Bodnar, I. V.; Arushanov, E.; Lisunov, K. G.

    2016-11-01

    Resistivity, ρ(T, x), of Cu2Zn(Sn x Ge1-x )Se4 (CZTGeSe) single crystals with x  =  0-1, investigated at temperatures between T ~ 10-320 K, exhibits an activated character within the whole temperature range, attaining a minimum at x  =  0.47. Magnetoresistance (MR) of CZTGeSe with x  =  0.26, 0.47 and 0.64 is positive (pMR) in all measured fields of B up to 20 T at any T between ~40-320 K, whereas MR of samples with x  =  0 and 1 contains a negative contribution (nMR). The dependence of ρ(T) at B  =  0 gives evidence for a nearest-neighbor hopping (NNH) conductivity in high-temperature intervals within T ~ 200-320 K depending on x, followed by the Mott variable-range hopping (VRH) charge transfer with lowering temperature. The pMR law of lnρ(B) \\propto B 2 is observed in both hopping conductivity regimes above, provided that the nMR contribution is absent or saturated. Analysis of the ρ(T) and MR data has yielded the values of the NNH activation energy and the VRH characteristic temperature, as well as those of the acceptor band width, the acceptor concentration, the localization radii of holes and the density of the localized states (DOS) at the Fermi level. All the parameters above exhibit a systematic non-monotonous dependence on x. Their extremums, lying close to x  =  0.64, correspond to the minimum of a lattice disorder along with the maximum of DOS and of the acceptor concentration, as well as a highest proximity to the metal-insulator transition.

  7. Hopping magnetotransport of the band-gap tuning Cu2Zn(Sn x Ge1-x )Se4 crystals.

    Science.gov (United States)

    Lähderanta, E; Hajdeu-Chicarosh, E; Shakhov, M A; Guc, M; Bodnar, I V; Arushanov, E; Lisunov, K G

    2016-11-16

    Resistivity, ρ(T, x), of Cu2Zn(Sn x Ge1-x )Se4 (CZTGeSe) single crystals with x  =  0-1, investigated at temperatures between T ~ 10-320 K, exhibits an activated character within the whole temperature range, attaining a minimum at x  =  0.47. Magnetoresistance (MR) of CZTGeSe with x  =  0.26, 0.47 and 0.64 is positive (pMR) in all measured fields of B up to 20 T at any T between ~40-320 K, whereas MR of samples with x  =  0 and 1 contains a negative contribution (nMR). The dependence of ρ(T) at B  =  0 gives evidence for a nearest-neighbor hopping (NNH) conductivity in high-temperature intervals within T ~ 200-320 K depending on x, followed by the Mott variable-range hopping (VRH) charge transfer with lowering temperature. The pMR law of lnρ(B) [Formula: see text] B (2) is observed in both hopping conductivity regimes above, provided that the nMR contribution is absent or saturated. Analysis of the ρ(T) and MR data has yielded the values of the NNH activation energy and the VRH characteristic temperature, as well as those of the acceptor band width, the acceptor concentration, the localization radii of holes and the density of the localized states (DOS) at the Fermi level. All the parameters above exhibit a systematic non-monotonous dependence on x. Their extremums, lying close to x  =  0.64, correspond to the minimum of a lattice disorder along with the maximum of DOS and of the acceptor concentration, as well as a highest proximity to the metal-insulator transition.

  8. Backoff-stage synchronization in three-hop string-topology wireless networks with hidden nodes

    Science.gov (United States)

    Sanada, Kosuke; Sekiya, Hiroo; Komuro, Nobuyoshi; Sakata, Shiro

    In IEEE 802.11 wireless multi-hop networks, each node works individually and their individual operations generate entire network dynamics. It is important to clarify the network dynamics in wireless multi-hop networks for designing and constructing multi-hop communication networks. This paper presents the network-dynamics investigations for three-hop string-topology wireless network in detail. From the investigations, a “backoff-stage synchronization” phenomenon, which is mutuality between hidden nodes, is found. The mechanism of the backoff-stage synchronization is expressed and the sufficient conditions for the synchronization occurrence are given. This phenomenon gives some impacts on the IEEE 802.11 multi-hop-network communications.

  9. Protein structure prediction: assembly of secondary structure elements by basin-hopping.

    Science.gov (United States)

    Hoffmann, Falk; Vancea, Ioan; Kamat, Sanjay G; Strodel, Birgit

    2014-10-20

    The prediction of protein tertiary structure from primary structure remains a challenging task. One possible approach to this problem is the application of basin-hopping global optimization combined with an all-atom force field. In this work, the efficiency of basin-hopping is improved by introducing an approach that derives tertiary structures from the secondary structure assignments of individual residues. This approach is termed secondary-to-tertiary basin-hopping and benchmarked for three miniproteins: trpzip, trp-cage and ER-10. For each of the three miniproteins, the secondary-to-tertiary basin-hopping approach successfully and reliably predicts their three-dimensional structure. When it is applied to larger proteins, correctly folded structures are obtained. It can be concluded that the assembly of secondary structure elements using basin-hopping is a promising tool for de novo protein structure prediction.

  10. Potential use ofGarcinia kola as hop substitute in lager beer brewing.

    Science.gov (United States)

    Aniche, G N; Uwakwe, G U

    1990-09-01

    The chemical, brewing and anti-microbial properties of a tropical seed,Garcinia kola, were compared with traditional hops. Treatment ofGarcinia kola with methanolic lead acetate produced a yellow precipitate from which organic acids (alpha acids) were contirmed to be present by thin-layer chromatography. Hops, however, had a higher concentration of organic acids thanGarcinia kola. Laboratory brewing trials withGarcinia kola and hops gave beers with simillar chemical properties. Organoleptically,Garcinia kola beer was as acceptable to tasters as hopped beer except that it had an improved bitterness.Garcinia kola and hop extracts exerted similar anti-microbial effects on two beer spollage micro-organisms (Lactobacillus delbruckii andCandida vini).

  11. Research on ADV-Hop localization algorithm in wireless sensor networks

    Science.gov (United States)

    Zhao, Shijun; Xu, Xiulan; Zhang, Zhaohui; Sun, Meiling

    2008-10-01

    Wireless sensor networks (WSN) have wide applicability to many important applications including environmental monitoring, military applications and disaster management, etc. In many applications, sensors are assumed to know their absolute locations. Some localization methods of WSN have been proposed. In these methods, nodes equipped with GPS to get precise location information, namely the anchor nodes, are employed to derive the locations of other nodes. Most of the recent work focuses on increasing the accuracy in position estimation. In this paper, aiming at the high communication cost and average positioning error of DV-hop algorithm, an advanced algorithm which is called ADV-hop algorithm is proposed. Simulations are made by the network simulator NS2. The simulation results show that ADV-hop algorithm has lower communication cost and smaller average positioning error than DV-hop algorithm, which makes ADV-hop algorithm more suitable for the node location of WSN.

  12. Ubiquitous picture-rich content representation

    Science.gov (United States)

    Wang, Wiley; Dean, Jennifer; Muzzolini, Russ

    2010-02-01

    The amount of digital images taken by the average consumer is consistently increasing. People enjoy the convenience of storing and sharing their pictures through online (digital) and offline (traditional) media. A set of pictures can be uploaded to: online photo services, web blogs and social network websites. Alternatively, these images can be used to generate: prints, cards, photo books or other photo products. Through uploading and sharing, images are easily transferred from one format to another. And often, a different set of associated content (text, tags) is created across formats. For example, on his web blog, a user may journal his experiences of his recent travel; on his social network website, his friends tag and comment on the pictures; in his online photo album, some pictures are titled and keyword-tagged. When the user wants to tell a complete story, perhaps in a photo book, he must collect, across all formats: the pictures, writings and comments, etc. and organize them in a book format. The user has to arrange the content of his trip in each format. The arrangement, the associations between the images, tags, keywords and text, cannot be shared with other formats. In this paper, we propose a system that allows the content to be easily created and shared across various digital media formats. We define a uniformed data association structure to connect: images, documents, comments, tags, keywords and other data. This content structure allows the user to switch representation formats without reediting. The framework under each format can emphasize (display or hide) content elements based on preference. For example, a slide show view will emphasize the display of pictures with limited text; a blog view will display highlighted images and journal text; and the photo book will try to fit in all images and text content. In this paper, we will discuss the strategy to associate pictures with text content, so that it can naturally tell a story. We will also list

  13. RNAi knockdown of Hop (Hsp70/Hsp90 organising protein) decreases invasion via MMP-2 down regulation.

    Science.gov (United States)

    Walsh, Naomi; Larkin, AnneMarie; Swan, Niall; Conlon, Kevin; Dowling, Paul; McDermott, Ray; Clynes, Martin

    2011-07-28

    We previously identified Hop as over expressed in invasive pancreatic cancer cell lines and malignant tissues of pancreatic cancer patients, suggesting an important role for Hop in the biology of invasive pancreatic cancer. Hop is a co-chaperone protein that binds to both Hsp70/Hsp90. We hypothesised that by targeting Hop, signalling pathways modulating invasion and client protein stabilisation involving Hsp90-dependent complexes may be altered. In this study, we show that Hop knockdown by small interfering (si)RNA reduces the invasion of pancreatic cancer cells, resulting in decreased expression of the downstream target gene, matrix metalloproteinases-2 (MMP-2). Hop in conditioned media co-immunoprecipitates with MMP-2, implicating a possible extracellular function for Hop. Knockdown of Hop expression also reduced expression levels of Hsp90 client proteins, HER2, Bcr-Abl, c-MET and v-Src. Furthermore, Hop is strongly expressed in high grade PanINs compared to lower PanIN grades, displaying differential localisation in invasive ductal pancreatic cancer, indicating that the localisation of Hop is an important factor in pancreatic tumours. Our data suggests that the attenuation of Hop expression inactivates key signal transduction proteins which may decrease the invasiveness of pancreatic cancer cells possibly through the modulation of Hsp90 activity. Therefore, targeting Hop in pancreatic cancer may constitute a viable strategy for targeted cancer therapy.

  14. Engaging Black Males on Their Own Terms: What Schools Can Learn from Black Males Who Produce Hip-Hop

    Science.gov (United States)

    Irby, Decoteau J.; Petchauer, Emery; Kirkland, David

    2013-01-01

    Education scholars and practitioners have much to learn about engagement and motivation of Black males by directing their inquiries to more organic sites of hip-hop cultural production outside of schools. One such site is the hip-hop's informal labor economy where Black males engage in earning money through hip-hop cultural production. Labor…

  15. RNAi knockdown of Hop (Hsp70/Hsp90 organising protein) decreases invasion via MMP-2 down regulation.

    LENUS (Irish Health Repository)

    Walsh, Naomi

    2011-07-28

    We previously identified Hop as over expressed in invasive pancreatic cancer cell lines and malignant tissues of pancreatic cancer patients, suggesting an important role for Hop in the biology of invasive pancreatic cancer. Hop is a co-chaperone protein that binds to both Hsp70\\/Hsp90. We hypothesised that by targeting Hop, signalling pathways modulating invasion and client protein stabilisation involving Hsp90-dependent complexes may be altered. In this study, we show that Hop knockdown by small interfering (si)RNA reduces the invasion of pancreatic cancer cells, resulting in decreased expression of the downstream target gene, matrix metalloproteinases-2 (MMP-2). Hop in conditioned media co-immunoprecipitates with MMP-2, implicating a possible extracellular function for Hop. Knockdown of Hop expression also reduced expression levels of Hsp90 client proteins, HER2, Bcr-Abl, c-MET and v-Src. Furthermore, Hop is strongly expressed in high grade PanINs compared to lower PanIN grades, displaying differential localisation in invasive ductal pancreatic cancer, indicating that the localisation of Hop is an important factor in pancreatic tumours. Our data suggests that the attenuation of Hop expression inactivates key signal transduction proteins which may decrease the invasiveness of pancreatic cancer cells possibly through the modulation of Hsp90 activity. Therefore, targeting Hop in pancreatic cancer may constitute a viable strategy for targeted cancer therapy.

  16. Photon assisted long-range tunneling

    Energy Technology Data Exchange (ETDEWEB)

    Gallego-Marcos, Fernando; Sánchez, Rafael; Platero, Gloria [Instituto de Ciencia de Materiales, CSIC, Cantoblanco, 28049 Madrid (Spain)

    2015-03-21

    We analyze long-range transport through an ac driven triple quantum dot with a single electron. Resonant transitions between separated and detuned dots are mediated by the exchange of n photons with the time-dependent field. An effective model is proposed in terms of second order (cotunneling) processes which dominate the long-range transport between the edge quantum dots. The ac field renormalizes the inter dot hopping, modifying the level hybridization. It results in a non-trivial behavior of the current with the frequency and amplitude of the external ac field.

  17. Electrocortical processing of food and emotional pictures in anorexia nervosa and bulimia nervosa.

    Science.gov (United States)

    Blechert, Jens; Feige, Bernd; Joos, Andreas; Zeeck, Almut; Tuschen-Caffier, Brunna

    2011-06-01

    Objective To compare the electrocortical processing of food pictures in participants with anorexia nervosa (n = 21), bulimia nervosa (n = 22), and healthy controls (HCs) (n = 32) by measuring the early posterior negativity, an event-related potential that reflects stimulus salience and selective attention. Methods We exposed these three groups to a rapid stream of high- and low-calorie food pictures, as well as standard emotional and neutral pictures. Results Event-related potentials in the time range of 220 milliseconds to 310 milliseconds on posterior electrodes differed between groups: patients with eating disorders showed facilitated processing of both high- and low-calorie food pictures relative to neutral pictures, whereas HC participants did so only for the high-calorie pictures. Subjective palatability of the pictures was rated highest by patients with anorexia nervosa, followed by the HC and bulimia nervosa groups. Conclusions Patients with eating disorders show a generalized attentional bias for food images, regardless of caloric value. This might explain the persistent preoccupation with food in these individuals.

  18. An improved DV-Hop algorithm based on genetic algorithm%遗传算法的 DV-Hop 算法改进

    Institute of Scientific and Technical Information of China (English)

    张万礼; 宋启祥

    2015-01-01

    DV-Hop 算法中,平均每跳距离是影响定位精度的因素之一。针对平均每跳距离带来的定位误差,对锚节点和未知节点的平均每跳距离进行了改进和优化。首先引入遗传算法计算锚节点的平均每跳距离;然后利用跳数小于等于3的锚节点的平均每跳距离加权处理未知节点的平均每跳距离,减少平均每跳距离带来的误差。仿真结果表明,在不增加硬件开销的基础上,改进算法能够有效提高算法的定位精度,并且具有较好的稳定性。%The average per-hop distance is one of the factors which affect the positioning accuracy in DV-Hop algorithm.Aiming at positioning errors caused by the average distance per hop,the average distance per hop of anchor nodes and unknown nodes have been improved and optimized in this paper.First,the average per hop distance of anchor nodes is computed by introducing genetic algorithm;Then the average distance per hop of the unknown node is weighted by using the average distance per hop of anchor nodes which hop count is less than or equal to 3 to reduce errors caused average distance per hop.Ultimately the accuracy of positioning is improved.Simulation results show that without additional hardware cost,the improved algorithm can effectively improve the positioning accuracy of the algorithm and has good stability.

  19. Neural correlates of processing negative and sexually arousing pictures.

    Directory of Open Access Journals (Sweden)

    Kira Bailey

    Full Text Available Recent work has questioned whether the negativity bias is a distinct component of affective picture processing. The current study was designed to determine whether there are different neural correlates of processing positive and negative pictures using event-related brain potentials. The early posterior negativity and late positive potential were greatest in amplitude for erotic pictures. Partial Least Squares analysis revealed one latent variable that distinguished erotic pictures from neutral and positive pictures and another that differentiated negative pictures from neutral and positive pictures. The effects of orienting task on the neural correlates of processing negative and erotic pictures indicate that affective picture processing is sensitive to both stimulus-driven, and attentional or decision processes. The current data, together with other recent findings from our laboratory, lead to the suggestion that there are distinct neural correlates of processing negative and positive stimuli during affective picture processing.

  20. Neural Correlates of Processing Negative and Sexually Arousing Pictures

    Science.gov (United States)

    Bailey, Kira; West, Robert; Mullaney, Kellie M.

    2012-01-01

    Recent work has questioned whether the negativity bias is a distinct component of affective picture processing. The current study was designed to determine whether there are different neural correlates of processing positive and negative pictures using event-related brain potentials. The early posterior negativity and late positive potential were greatest in amplitude for erotic pictures. Partial Least Squares analysis revealed one latent variable that distinguished erotic pictures from neutral and positive pictures and another that differentiated negative pictures from neutral and positive pictures. The effects of orienting task on the neural correlates of processing negative and erotic pictures indicate that affective picture processing is sensitive to both stimulus-driven, and attentional or decision processes. The current data, together with other recent findings from our laboratory, lead to the suggestion that there are distinct neural correlates of processing negative and positive stimuli during affective picture processing. PMID:23029071

  1. The Work of the Motion Picture Cameraman.

    Science.gov (United States)

    Young, Freddie; Petzold, Paul

    Meant to serve as an authoritative source of information on camera work in large scale feature productions, this book attempts to give some basic understanding of the problems of motion picture photography, the working conditions and artistry of lighting for mood and dramatic effect, budget problems for making films, and facts about working with a…

  2. The Last Great American Picture Show

    NARCIS (Netherlands)

    Elsaesser, Thomas; King, Noel; Horwath, Alexander

    2004-01-01

    The Last Great American Picture Show brings together essays by scholars and writers who chart the changing evaluations of the American cinema of the 1970s, sometimes referred to as the decade of the lost generation, but now more and more recognized as the first New Hollywood, without which the cinem

  3. Learning about Environmental Print through Picture Books.

    Science.gov (United States)

    Kuby, Patricia; And Others

    1996-01-01

    Describes picture books that contain environmental print (print found in the natural environment of a child, such as logos, billboards, and road signs) and how they can be used in the classroom. Includes "ABC Drive!" by Naomi Howland (1994), "The Signmaker's Assistant" by Tedd Arnold (1992), and four others. Also provides a…

  4. North America - The Energy Picture II

    Science.gov (United States)

    2006-01-01

    Servicio Público de Energía Eléctrica or LSPEE) was amended to allow private participation in generation activities. Article 3 of this Act lists...Desarrollo Urbano ), of the National Urban System (Sistema Urbano Nacional), and of the specific urban North America – The Energy Picture II

  5. Bilingual Picture Books: Libros Para Todos.

    Science.gov (United States)

    Agosto, Denise

    1997-01-01

    Discusses the importance of including bilingual English/Spanish picture books in library collections, introduces some recent titles, and describes some programming ideas. Topics include second language study, children teaching English to Spanish-speaking parents, cultural studies, and bilingual presentations. (LRW)

  6. Perseverant Responding in Children's Picture Naming

    Science.gov (United States)

    Booth, Josephine; Vitkovitch, Melanie

    2008-01-01

    Two groups of children were given pictures of animals to name as quickly as they could. The groups comprised 40 nursery aged children (mean age 3 ; 11) and 40 Year 2 children (mean age 6 ; 9) attending primary school in London. The 30 animals were presented one by one, on cards, and any errors made by the children were noted. Consistent with a…

  7. Bilingual Picture Books: Libros Para Todos.

    Science.gov (United States)

    Agosto, Denise

    1997-01-01

    Discusses the importance of including bilingual English/Spanish picture books in library collections, introduces some recent titles, and describes some programming ideas. Topics include second language study, children teaching English to Spanish-speaking parents, cultural studies, and bilingual presentations. (LRW)

  8. Princess Picture Books: Content and Messages

    Science.gov (United States)

    Dale, Lourdes P.; Higgins, Brittany E.; Pinkerton, Nick; Couto, Michelle; Mansolillo, Victoria; Weisinger, Nica; Flores, Marci

    2016-01-01

    Because many girls develop their understanding of what it means to be a girl from books about princesses, the researchers coded the messages and content in 58 princess books (picture, fairy tales, and fractured fairy tales). Results indicate that gender stereotypes are present in the books--the princesses were more likely to be nurturing, in…

  9. Young Children, National Tragedy, and Picture Books.

    Science.gov (United States)

    McMath, Joan S.

    1997-01-01

    Suggests that, rather than exposing young children to media coverage of national tragedies and disasters, caregivers should read aloud to children from picture books that convey stability, calmness, and reassurance. Includes tips for helping children cope with tragedy, guidelines for selecting books, and an annotated list of 25 books that can help…

  10. Motion Picture and Videotape Analysis of Behavior.

    Science.gov (United States)

    Carpenter, Geoffrey C.; Duvall, David

    1983-01-01

    Use of motion pictures and videotape recordings to analyze animal behavior is described. Indicates that accuracy/amount of data available is greatly increased and that simultaneous behaviors of different animals can be studied or individual behavior patterns increased/decreased, providing observers with temporal perceptions similar to the animals…

  11. Learning about Environmental Print through Picture Books.

    Science.gov (United States)

    Kuby, Patricia; And Others

    1996-01-01

    Describes picture books that contain environmental print (print found in the natural environment of a child, such as logos, billboards, and road signs) and how they can be used in the classroom. Includes "ABC Drive!" by Naomi Howland (1994), "The Signmaker's Assistant" by Tedd Arnold (1992), and four others. Also provides a bibliography of other…

  12. Do Natural Pictures Mean Natural Tastes?

    DEFF Research Database (Denmark)

    Smith, Viktor; Barratt, Daniel; Sørensen, Henrik Selsøe

    2015-01-01

    A widespread assumption in Danish consumer law is that if the package of a food product carries a picture of a potentially taste-giving ingredient (say, a strawberry), then consumers will expect the corresponding taste to stem primarily from that ingredient rather than from artificial flavouring...

  13. Surface hopping investigation of the relaxation dynamics in radical cations

    Energy Technology Data Exchange (ETDEWEB)

    Assmann, Mariana; Matsika, Spiridoula, E-mail: smatsika@temple.edu [Department of Chemistry, Temple University, Philadelphia, Pennsylvania 19122 (United States); Weinacht, Thomas [Department of Physics, Stony Brook University, Stony Brook, New York 11794 (United States)

    2016-01-21

    Ionization processes can lead to the formation of radical cations with population in several ionic states. In this study, we examine the dynamics of three radical cations starting from an excited ionic state using trajectory surface hopping dynamics in combination with multiconfigurational electronic structure methods. The efficiency of relaxation to the ground state is examined in an effort to understand better whether fragmentation of cations is likely to occur directly on excited states or after relaxation to the ground state. The results on cyclohexadiene, hexatriene, and uracil indicate that relaxation to the ground ionic state is very fast in these systems, while fragmentation before relaxation is rare. Ultrafast relaxation is facilitated by the close proximity of electronic states and the presence of two- and three-state conical intersections. Examining the properties of the systems in the Franck-Condon region can give some insight into the subsequent dynamics.

  14. New prenylchalcones from the hops of Humulus lupulus.

    Science.gov (United States)

    Wang, Wen-Shu; Ye, Yun-Hua; Zhou, Ya-Wei

    2008-01-01

    Two new prenylchalcones, xanthohumol C and D, together with two known prenylchalcone derivatives, xanthohumol (1) and 5''-(2''-hydroxyisopropyl)-dihydrofurano-[2'',3''-b]-4,4'-dihydroxy-6'-methoxy-chalcone (4) were isolated and identified from the hops of Humulus lupulus L. The structures of xanhohumol C and D were elucidated as 5''-hydroxy-6'',6''-dimethyl-dihydropyrano-[2'',3''-b]-4,4'-dihydroxy-6'-methoxy-chalcone (2) and 5''-hydroxy-6'',6''-dimethyl-dihydropyrano-[2'',3''-b]-4',6'-dimethoxy-4-hydroxy-chalcone (3) on the basis of HRFAB-MS, 1D and 2D NMR (HMQC, HMBC) spectroscopic data. Among the new prenylchalcones, compound 2 showed marginal cytotoxic activity against human stomach carcinoma BGC-823 and human hepatic carcinoma HepG2 cells.

  15. SDN-Based Double Hopping Communication against Sniffer Attack

    Directory of Open Access Journals (Sweden)

    Zheng Zhao

    2016-01-01

    Full Text Available Sniffer attack has been a severe threat to network communication security. Traditional network usually uses static network configuration, which provides convenience to sniffer attack. In this paper, an SDN-based double hopping communication (DHC approach is proposed to solve this problem. In DHC, ends in communication packets as well as the routing paths are changed dynamically. Therefore, the traffic will be distributed to multiple flows and transmitted along different paths. Moreover, the data from multiple users will be mixed, bringing difficulty for attackers in obtaining and recovering the communication data, so that sniffer attack will be prevented effectively. It is concluded that DHC is able to increase the overhead of sniffer attack, as well as the difficulty of communication data recovery.

  16. SHOP: scaffold hopping by GRID-based similarity searches

    DEFF Research Database (Denmark)

    Bergmann, Rikke; Linusson, Anna; Zamora, Ismael

    2007-01-01

    A new GRID-based method for scaffold hopping (SHOP) is presented. In a fully automatic manner, scaffolds were identified in a database based on three types of 3D-descriptors. SHOP's ability to recover scaffolds was assessed and validated by searching a database spiked with fragments of known...... ligands of three different protein targets relevant for drug discovery using a rational approach based on statistical experimental design. Five out of eight and seven out of eight thrombin scaffolds and all seven HIV protease scaffolds were recovered within the top 10 and 31 out of 31 neuraminidase...... scaffolds were in the 31 top-ranked scaffolds. SHOP also identified new scaffolds with substantially different chemotypes from the queries. Docking analysis indicated that the new scaffolds would have similar binding modes to those of the respective query scaffolds observed in X-ray structures...

  17. Nonregenerative Dual-Hop Cooperative Links with Selection Diversity

    Directory of Open Access Journals (Sweden)

    Karagiannidis George K

    2006-01-01

    Full Text Available The end-to-end performance of dual-hop cooperative diversity systems equipped with nonregenerative relays and a selection combining receiver at the destination terminal over independent and nonidentical Nakagami- fading channels is studied. Closed-form expressions for the cumulative distribution function and the probability density function of the end-to-end signal-to-noise ratio ( are presented, while analytical formulae are derived for the moments and the moment generating function. Using these statistical results, closed-form expressions for the outage probability are presented for both channel state information and fixed gain relays. Furthermore, for the case of fixed gain relay, the average end-to-end , the amount of fading, and the average bit error rate can be numerically evaluated. The proposed mathematical analysis is complemented by numerical examples, including the effects on the overall performance of the s unbalancing as well as the fading severity.

  18. Cipher quasi-chaotic code for frequency hopping communications

    Institute of Scientific and Technical Information of China (English)

    王宏霞; 何晨; 虞厥邦

    2004-01-01

    The chaotic frequency hopping (FH) communication systems have been presented so far. The chaotic sequences possesses good randomness and sensitive dependence on initial conditions, which is quite advantageous to run the FH codes in code-division multiple access (CDMA) systems. But the finite precision of computation and the fact of the low-dimensional chaos predicted easily cause difficulty in chaotic application. In this paper, some disadvantages associated with the conventional FH codes and the chaotic code scrambled by m-sequences are reviewed briefly. In order to overcome these drawbacks to some extents, a new higher performance FH code called cipher quasi-chaotic (CQC) code is proposed,which is generated by combining the clock-controlled stream cipher technique and chaotic dynamics. Performance analysis applying in FH communication systems of this kind of code is given. The privacy of the CQC sequence is also analyzed.

  19. HIP HOP: A CORPORAL PRACTICE (EXPRESSION) THAT TERRITORIALIZE MEDELLIN CITY

    OpenAIRE

    Hincapié, Astrid

    2014-01-01

    Este artículo es un producto asociado a la investigación La apropiación de las prácticas corporales urbanas de danza en la juventud de la ciudad de Medellín – Comuna 13 (Col.), realizada en la maestría en Motricidad y Desarrollo Humano de la Universidad de Antioquia. En él se indaga, a través de una etnografía urbana,  sobre la manera como los jóvenes de la ciudad configuran un territorio cultural por medio de la práctica del hip hop. Arte juvenil que se desarrolla en medio de las tensiones q...

  20. Positive erotic picture stimuli for emotion research in heterosexual females.

    Science.gov (United States)

    Jacob, Gitta Anne; Arntz, Arnoud; Domes, Gregor; Reiss, Neele; Siep, Nicolette

    2011-12-30

    In most experimental studies, emotional pictures are widely used as stimulus material. However, there is still a lack of standardization of picture stimuli displaying erotic relationships, despite the association between a number of psychological problems and severe impairments and problems in intimate relationships. The aim of the study was to test a set of erotic stimuli, with the potential to be used in experimental studies, with heterosexual female subjects. Twenty International Affective Picture System (IAPS) pictures and an additional 100 pictures showing romantic but not explicitly sexual scenes and/or attractive single males were selected. All pictures were rated with respect to valence, arousal, and dominance by 41 heterosexual women and compared to pictures with negative, positive, and neutral emotional valence. Erotic IAPS pictures and our additional erotic pictures did not differ in any of the evaluation dimensions. Analyses of variance (ANOVAs) for valence, arousal, and dominance comparing different picture valence categories showed strong effects for category. However, valence was not significantly different between erotic and positive pictures, while arousal and control were not significantly different between positive and neutral pictures. The pictures of our new set are as positive for heterosexual women as highly positive IAPS pictures, but higher in arousal and dominance. The picture set can be used in experimental psychiatric studies requiring high numbers of stimuli per category. Limitations are the restriction of stimuli application to heterosexual females only and to self-report data. Copyright © 2011 Elsevier Ltd. All rights reserved.

  1. The Association Between Knee Confidence and Muscle Power, Hop Performance, and Postural Orientation in People With Anterior Cruciate Ligament Injury.

    Science.gov (United States)

    Ageberg, Eva; Roos, Ewa M

    2016-06-01

    Study Design Cross-sectional. Background The association between muscle function and lack of knee confidence in people with anterior cruciate ligament (ACL) injury has not been well investigated. Such knowledge would help in the design of training programs for this population. Objective To investigate associations between self-reported knee confidence and muscle function in patients with ACL injury. Methods Cross-sectional data from 54 patients (mean age, 30 years; range, 20-39 years; 28% women) with ACL injury, treated with training and reconstructive surgery (n = 36) or training only (n = 18), were assessed 3 ± 1 years after injury. Univariate and multivariable ordinal regression analyses were conducted to test the association between the patient's knee confidence (question 3 from the Knee injury and Osteoarthritis Outcome Score as the dependent variable) and performance on tests of muscle power, hop performance, and postural orientation (test for substitution patterns score) as independent variables (absolute value on the injured leg, and limb symmetry index [LSI; injured leg/uninjured leg × 100] or absolute difference between the injured and uninjured legs). Results Sixteen patients reported no trouble with lack of knee confidence, 24 mild trouble, 10 moderate trouble, and 4 severe or extreme trouble. Univariate analyses revealed significant associations between worse knee confidence and lower (worse) LSIs for knee extension power, vertical jump, and side hop, and worse test for substitution patterns scores. In the multivariable analysis, worse vertical jump LSI (P = .043) and worse side hop LSI (P = .012) significantly accounted for 25% of the variation in perceived knee confidence. Conclusion Between-leg differences during demanding tasks are associated with knee confidence in individuals with ACL injury. J Orthop Sports Phys Ther 2016;46(6):477-482. Epub 26 Apr 2016. doi:10.2519/jospt.2016.6374.

  2. Non-linear effects in hopping conduction of single-crystal La2CuO4 + δ

    Science.gov (United States)

    Belevtsev, B. I.; Dalakova, N. V.; Panfilov, A. S.

    1998-11-01

    The unusual non-linear effects in hopping conduction of single-crystal La2CuO4+δ with excess oxygen has been observed. The resistance is measured as a function of the applied voltage U (voltage controlled regime) in the temperature range 5 K⩽T⩽300 K and voltage range 10-3-25 V. At relatively high voltage (approximately at U>0.1 V) the conduction of sample investigated corresponds well to variable-range hopping (VRH). That is, in the range 0.1 Vconductivity does not depend on U (Ohmic behavior) and the temperature dependence of resistance R(T) follows closely Mott's law of VRH [R∝exp(T0/T)1/4]. In the range of highest applied voltage the conduction has been non-Ohmic: the resistance decreases with increasing U. This non-linear effect is quite expected in the frame of VRH mechanism, since the applied electric field increases the hopping probability. A completely different and unusual conduction behavior is found, however, in the low voltage range (approximately below 0.1 V), where the influence of electric field and (or) electron heating effect on VRH ought to be neglected. Here we have observed strong increase in resistance at increasing U at T⩽20 K, whereas at T>20 K the resistance decreases with increasing U. The magnetoresistance of the sample below 20 K has been positive at low voltage and negative at high voltage. The observed unusual non-Ohmic behavior at low voltage range is attributable to inhomogeneity of the sample, namely, to the enrichment of sample surface with oxygen during the course of the heat treatment of the sample in helium and air atmosphere before measurements. At low enough temperature (below ≈20 K) the surface layer with increased oxygen concentration is presumed to consist of disconnected superconducting regions in a poorly conducting (dielectric) matrix. This allows us to explain the observed unusual non-linear effects in the conduction of sample studied. The results obtained demonstrate that in some cases the measured transport

  3. Understanding hopping transport and thermoelectric properties of conducting polymers

    Science.gov (United States)

    Ihnatsenka, S.; Crispin, X.; Zozoulenko, I. V.

    2015-07-01

    We calculate the conductivity σ and the Seebeck coefficient S for the phonon-assisted hopping transport in conducting polymers poly(3,4-ethylenedioxythiophene) or PEDOT, experimentally studied by Bubnova et al. [J. Am. Chem. Soc. 134, 16456 (2012)], 10.1021/ja305188r. We use the Monte Carlo technique as well as the semianalytical approach based on the transport energy concept. We demonstrate that both approaches show a good qualitative agreement for the concentration dependence of σ and S . At the same time, we find that the semianalytical approach is not in a position to describe the temperature dependence of the conductivity. We find that both Gaussian and exponential density of states (DOS) reproduce rather well the experimental data for the concentration dependence of σ and S giving similar fitting parameters of the theory. The obtained parameters correspond to a hopping model of localized quasiparticles extending over 2-3 monomer units with typical jumps over a distance of 3-4 units. The energetic disorder (broadening of the DOS) is estimated to be 0.1 eV. Using the Monte Carlo calculation we reproduce the activation behavior of the conductivity with the calculated activation energy close to the experimentally observed one. We find that for a low carrier concentration a number of free carriers contributing to the transport deviates strongly from the measured oxidation level. Possible reasons for this behavior are discussed. We also study the effect of the dimensionality on the charge transport by calculating the Seebeck coefficient and the conductivity for the cases of three-, two-, and one-dimensional motion.

  4. Performance Evaluation of Two-Hop Wireless Link under Nakagami-m Fading

    Directory of Open Access Journals (Sweden)

    Afsana Nadia

    2013-08-01

    Full Text Available Now-a-days, intense research is going on two-hop wireless link under different fading conditions with its remedial measures. In this paper work, a two-hop link under three different conditions is considered: (i MIMO on both hops, (ii MISO in first hop and SIMO in second hop and finally (iii SIMO in first hop and MISO in second hop. The three models used here give the flexibility of using STBC (Space Time Block Coding and combining scheme on any of the source to relay (S-R and relay to destination (R-D link. Even incorporation of Transmitting Antenna Selection (TAS is possible on any link. Here, the variation of SER (Symbol Error Rate is determined against mean SNR (Signal-to-Noise Ratio of R-D link for three different modulation schemes: BPSK, 8-PSK and 16-PSK, taking the number of antennas and SNR of S-R link as parameters under Nakagami -m fading condition.

  5. Agronomic performance and beer quality assessment of twenty hop cultivars grown in Central Italy

    Directory of Open Access Journals (Sweden)

    Francesco Rossini

    2016-08-01

    Full Text Available Hop market and beer industry have always been of secondary relevance in Italy as compared to grape and wine sector. Hence, hop cultivars and the information for growing hops have been generated almost entirely from the major hop production countries. Identifying cultivars that perform well in Mediterranean environments is therefore essential to successfully start hop cultivation and breeding activity in this new growing region. To evaluate the intraspecific diversity of hop in Central Italy, 20 female hop genotypes with different origin were screened during three growing seasons (2013-2015 in an experimental hop yard. Cones yield, plant height and crop phenology were evaluated to determine which cultivars were best suited to the Mediterranean climate. Moreover, given the rising interest for the development of local beers with distinguishing aroma, a sensory analysis was performed and beers flavoured with locally produced and imported cones were compared. A significant diversity among cultivars was found for all parameters investigated. The results indicated that weather condition during flowering and development of cones markedly affected yield and plant height. Cones yield was negatively correlated with thermal time (r=–0.5, P<0.05 to harvest and positively with plant height (r=0.56, P<0.05. Cascade, Hallertauer Magnum, Hersbrucker Spat and Yeoman showed the best adaptability to the Mediterranean growing conditions as they were the top-performing cultivars across the three years. Sensory analysis evidenced the importance of cultivar selection as determining factor for flavouring properties of beers. In general, results showed that the origin of cones strongly affected the mouth feel of beers. More complex and appreciated aroma profiles were identified for beers flavoured with local cones than those hopped with commercial products.

  6. Get the picture? The effects of iconicity on toddlers' reenactment from picture books.

    Science.gov (United States)

    Simcock, Gabrielle; DeLoache, Judy

    2006-11-01

    What do toddlers learn from everyday picture-book reading interactions? To date, there has been scant research exploring this question. In this study, the authors adapted a standard imitation procedure to examine 18- to 30-month-olds' ability to learn how to reenact a novel action sequence from a picture book. The results provide evidence that toddlers can imitate specific target actions on novel real-world objects on the basis of a picture-book interaction. Children's imitative performance after the reading interaction varied both as a function of age and the level of iconicity of the pictures in the book. These findings are discussed in terms of children's emerging symbolic capacity and the flexibility of the cognitive representation.

  7. Peculiarities of hopping conduction in p-Hg sub 0 sub . sub 7 sub 8 Cd sub 0 sub . sub 2 sub 2 Te crystals at binary doping

    CERN Document Server

    Bogoboyashchij, V V

    2002-01-01

    Electric conductivity and the Hall effect within the 4.2-125 K temperature range have been investigated in p-Hg sub 0 sub . sub 7 sub 8 Cd sub 0 sub . sub 2 sub 2 Te crystals, containing 3 x 10 sup 1 sup 6 cm sup - sup 3 of copper impurities and 1.83 x 10 sup 1 sup 6 cm sup - sup 3 of mercury vacancies (together or separately). The epsilon sub 1 -conductivity due to free holes above 10-12 K and the hopping conductivity below 8-10 K are dominant in such crystals respectively. It was found that the epsilon sub 1 -conductivity in copper-doped crystals is independent of the vacancy presence, while the hopping conductivity essentially increases due to the vacancy availability. This phenomenon is explained in terms hole joining neutral mercury vacancies.The binding energy is calculated; it equal 3.7 meV in background state

  8. Falicov-Kimball model extended by pair hopping of d-electrons

    Science.gov (United States)

    Ghosh, N. K.; Mukherjee, P.

    2016-05-01

    The effect of the pair hopping of d-electrons has been examined in an exact diagonalization techniqueon a four-site square cluster using extended Falicov-Kimball model. This hopping interaction shifts the critical f-level energy (Ec) at which valence transition occurs. Sharp peaks are observed in the specific heat curves and pair hopping decreases the peak height indicating a reduction in the number of density of states. Antiferromagnetic ordering as well as Curie-like behavior has been observed in the spin susceptibility (χ) characteristics.

  9. Falicov-Kimball model extended by pair hopping of d-electrons

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, N. K., E-mail: nkg@klyuniv.ac.in; Mukherjee, P., E-mail: piulim2008@gmail.com [Department of Physics, University of Kalyani, Kalyani-741235, West Bengal (India)

    2016-05-06

    The effect of the pair hopping of d-electrons has been examined in an exact diagonalization techniqueon a four-site square cluster using extended Falicov-Kimball model. This hopping interaction shifts the critical f-level energy (E{sub c}) at which valence transition occurs. Sharp peaks are observed in the specific heat curves and pair hopping decreases the peak height indicating a reduction in the number of density of states. Antiferromagnetic ordering as well as Curie-like behavior has been observed in the spin susceptibility (χ) characteristics.

  10. A variational surface hopping algorithm for the sub-Ohmic spin-boson model

    CERN Document Server

    Yao, Yao

    2013-01-01

    The Davydov D1 ansatz, which assigns an individual bosonic trajectory to each spin state, is an efficient, yet extremely accurate trial state for time-dependent variation of the the sub-Ohmic spin-boson model [J. Chem. Phys. 138, 084111 (2013)]. A surface hopping algorithm is developed employing the Davydov D1 ansatz to study the spin dynamics with a sub-Ohmic bosonic bath. The algorithm takes into account both coherent and incoherent dynamics of the population evolution in a unified manner, and compared with semiclassical surface hopping algorithms, hopping rates calculated in this work follow more closely the Marcus formula.

  11. Communication: The correct interpretation of surface hopping trajectories: How to calculate electronic properties

    Energy Technology Data Exchange (ETDEWEB)

    Landry, Brian R.; Falk, Martin J.; Subotnik, Joseph E. [Department of Chemistry, University of Pennsylvania, 231 S. 34th Street, Philadelphia, Pennsylvania 19104 (United States)

    2013-12-07

    In a recent paper, we presented a road map for how Tully's fewest switches surface hopping (FSSH) algorithm can be derived, under certain circumstances, from the mixed quantum-classical Liouville equation. In this communication, we now demonstrate how this new interpretation of surface hopping can yield significantly enhanced results for electronic properties in nonadiabatic calculations. Specifically, we calculate diabatic populations for the spin-boson problem using FSSH trajectories. We show that, for some Hamiltonians, without changing the FSSH algorithm at all but rather simply reinterpreting the ensemble of surface hopping trajectories, we recover excellent results and remove any and all ambiguity about the initial condition problem.

  12. Field-induced crossover from phonon to field assisted hopping conductivity in organic materials

    Science.gov (United States)

    Bourbie, D.

    2011-01-01

    Recently the change in temperature dependence of conductivity observed in polythiophene field-effect transistors has been attributed to field-induced metal-insulator transition. Under a high source-drain voltage, the conductivity becomes independent from temperature and depends exponentially on the inverse of the square root of electric field. In this paper we present a theoretical interpretation of this behavior in the framework of hopping mechanism. The ingredient of this model, is the energy gained from the electrical field is always larger than the energy difference between the localized states involved into the charge transitions, which induces a crossover from phonon-assisted hopping to field-assisted hopping.

  13. Wireless multi-hop network scenario emulation by controlling maximal error

    Institute of Scientific and Technical Information of China (English)

    Huizhou ZHAO; Xiaoming LI; Wei YAN

    2009-01-01

    A fundamental problem about Ad-hoc network emulation is how to emulate a wireless multi-hop network scenario in a fixed testbed, which, however, is scarcely discussed in depth by existing radio frequency (RF)control wireless network emulators. Therefore, in this article, we first formulate the wireless multi-hop scenario emulation problem based on RF-control, take controlling the maximal error as the solution mentality, and present an algorithm called the matching exact-solution condition algorithm. The experiment results show that the algorithm can solve the wireless multi-hop network scenario emulation problem and maximal error can be achieved.

  14. Optimal Design of Dual-Hop VLC/RF Communication System With Energy Harvesting

    KAUST Repository

    Rakia, Tamer

    2016-07-28

    In this letter, we consider a dual-hop heterogeneous visible light communication (VLC)/radio frequency (RF) communication system to extend the coverage of VLC systems. Besides detecting the information over VLC link, the relay is able to harvest energy from the first-hop VLC link, by extracting the direct current component of the received optical signal, and uses the harvested energy to retransmit the data to a mobile terminal over the second-hop RF link. We investigate the optimal design of the hybrid system in terms of data rate maximization.

  15. Reprint of "Affective picture processing as a function of preceding picture valence: an ERP analysis".

    Science.gov (United States)

    Schupp, Harald T; Schmälzle, Ralf; Flaisch, Tobias; Weike, Almut I; Hamm, Alfons O

    2013-03-01

    Event-related brain potential (ERP) studies consistently revealed that a relatively early (early posterior negativity; EPN) and a late (late positive potential; LPP) ERP component differentiate between emotional and neutral picture stimuli. Two studies examined the processing of emotional stimuli when preceded either by pleasant, neutral, or unpleasant context images. In both studies, distinct streams of six pictures were shown. In Study 1, hedonic context was alternated randomly across the 180 picture streams. In Study 2, hedonic context sequences were blocked, resulting in 60 preceding sequences of pleasant, neutral, and unpleasant context valence, respectively. The main finding was that the valence of the preceding picture sequence had no significant effect on the emotional modulation of the EPN and LPP components. However, previous results were replicated in that emotional stimulus processing was associated with larger EPN and LPP components as compared to neutral pictures. These findings suggest that the prioritized processing of emotional stimuli is primarily driven by the valence of the current picture. Copyright © 2013 Elsevier B.V. All rights reserved.

  16. The Complex Picture Test in Dementia

    Directory of Open Access Journals (Sweden)

    K. Gustaw Rothenberg

    2012-10-01

    Full Text Available The newly developed Complex Picture Test (CPT examines main cognitive domains, especially perceptual and visual-spatial abilities. The potential usefulness of the CPT in the assessment of dementia was evaluated. Patients with different forms of dementia [14 vascular dementia (VaD, 30 Alzheimer’s disease (AD, 6 Parkinson’s disease dementia (PDD], 12 subjects with mild cognitive impairment (MCI, and 30 matched controls were examined by the CPT, Mini-Mental State Examination (MMSE, the WAIS-R Digit Span subtest, and the Clock Drawing Test (CDT. The CPT consists of 10 complex pictures, each presenting characteristics paradoxically in opposition to each other. The subjects scored points for naming the object and noticing the paradox. One point was added for commenting on the paradox without prompting (3 points each picture/maximum of 30. CPT scores were significantly higher in the control group (mean ± SD, 29.46 ± 1.43 than in the AD, VaD, MCI, and PDD groups (13.1 ± 2.3, 16.9 ± 3.5, 23.2 ± 1.4, and 23.6 ± 3.4, respectively; p < 0.05. Significant positive correlations between MMSE, Digit Span, CDT, and CPT scores were observed (rho 0.76, 0.35, and 0.56, respectively. These data show perception of complex pictures being compromised in dementia. The correlation between CPT scores and MMSE scores suggests that tests may be used as a brief screening tool for dementia.

  17. Aestheticism in the Picture of Dorian Gray

    Institute of Scientific and Technical Information of China (English)

    康妮芝

    2009-01-01

    Aestheticism or aestheticism movement Was an impomuat phenomenon during the hter nineteenth century.Aestheticism advocated the phrase"art for art's sake".Oscar Wildewas the most famous aestheticism writer during the later nineteenth century in Enghnd.His novel the Picture of Dorian Gray was the representative show of his aestheticism thought.The passage mainly shows Wilde's aestheticism thought of the novel in three aspects.

  18. Phenomenology on the QCD dipole picture revisited

    CERN Document Server

    Lengyel, A I

    2003-01-01

    We perform an adjust to the most recent structure function data, considering the QCD dipole picture applied to ep scattering. The structure function F2 at small x and intermediate Q2 can be described by the model containing an economical number of free-parameters, which encodes the hard Pomeron physics. The longitudinal structure function and the gluon distribution are predicted without further adjustments. The data description is effective, whereas a resummed next-to-leading level analysis is deserved.

  19. The ideal subject distance for passport pictures.

    Science.gov (United States)

    Verhoff, Marcel A; Witzel, Carsten; Kreutz, Kerstin; Ramsthaler, Frank

    2008-07-04

    In an age of global combat against terrorism, the recognition and identification of people on document images is of increasing significance. Experiments and calculations have shown that the camera-to-subject distance - not the focal length of the lens - can have a significant effect on facial proportions. Modern passport pictures should be able to function as a reference image for automatic and manual picture comparisons. This requires a defined subject distance. It is completely unclear which subject distance, in the taking of passport photographs, is ideal for the recognition of the actual person. We show here that the camera-to-subject distance that is perceived as ideal is dependent on the face being photographed, even if the distance of 2m was most frequently preferred. So far the problem of the ideal camera-to-subject distance for faces has only been approached through technical calculations. We have, for the first time, answered this question experimentally with a double-blind experiment. Even if there is apparently no ideal camera-to-subject distance valid for every face, 2m can be proposed as ideal for the taking of passport pictures. The first step would actually be the determination of a camera-to-subject distance for the taking of passport pictures within the standards. From an anthropological point of view it would be interesting to find out which facial features allow the preference of a shorter camera-to-subject distance and which allow the preference of a longer camera-to-subject distance.

  20. A motion picture presentation of magnetic pulsations

    Science.gov (United States)

    Suzuki, A.; Kim, J. S.; Sugura, M.; Nagano, H.

    1981-01-01

    Using the data obtained from the IMS North American magnetometer network stations at high latitudes, a motion picture was made by a computer technique, describing time changes of Pc5 and Pi3 magnetic pulsation vectors. Examples of pulsation characteristics derived from this presentation are regional polarization changes including shifts of polarization demarcation lines, changes in the extent of an active region and its movement with time.

  1. A Spectrum is Worth a Thousand Pictures

    Science.gov (United States)

    Gelderman, Richard F.

    2006-12-01

    A wise astronomer once pointed out that if a picture is worth a thousand words, then a spectrum is worth a thousand pictures. Unfortunately, spectra are rarely emphasized in the introductory astronomy courses and few students exit such a course with any meaningful understanding or appreciation of spectroscopy. Part of the problem is lack of background knowledge; the typical introductory astronomy student has little experience with spectroscopy or atomic physics. Another issue is that spectra are not pretty pictures and are not intuitively understandable. We present and discuss a series of “minds-on” exercises and activities built into a college-level “stars, galaxies, and cosmology” intro astronomy course. The lessons are structured to help students improve their ability to recognize patterns and improve their ability to really see the details in front of them. Another goal is for students to realize there is “more than meets the eye” to learn how to discover “hidden” diagnostics, such as different sources of light their eyes see as white light. A curriculum that emphasizes spectroscopy also provides the opportunity to stress the story of the “Harvard Women,” a tale that bridges gender gaps and often humanizes scientists in the eyes of non-science majors. Finally, with a solid foundation in spectroscopy, students are better prepared to understand exciting topics such as Hubble’s Law and the importance of primordial nucleosynthesis.

  2. Cut and paste pictures in surrealism

    Directory of Open Access Journals (Sweden)

    Todić Milanka

    2006-01-01

    Full Text Available Proceeding from the idea of the readymade, Marko Ristić’s, Vane Bor’s and Dušan Matić’s collages regroup readymade pictorial and textual matrices according to the rules of free associative syntax. Everything that they collected cut out and pasted bears the hallmark of personal choice, i.e. objective chance, as the Surrealists would say. In the new structure of the collage, picture and text were of equal importance. However, we should not forget that both picture and text were only fragments, of different origin so that they could not function as autonomous elements in their own right nor could they establish logical interlinks. Cut and paste picture in Surrealism are primarily registered as visual wholes, in which the former principle of harmony has been substituted by the principle of discontinuity. In fact, they do not aspire to establish closed and unambiguous semantic structures either on a single paper or within a cycle, disregarding as they do conventional narrative and illustrative order in representing reality.

  3. Plasmodium falciparum Hop (PfHop Interacts with the Hsp70 Chaperone in a Nucleotide-Dependent Fashion and Exhibits Ligand Selectivity.

    Directory of Open Access Journals (Sweden)

    Tawanda Zininga

    Full Text Available Heat shock proteins (Hsps play an important role in the development and pathogenicity of malaria parasites. One of the most prominent functions of Hsps is to facilitate the folding of other proteins. Hsps are thought to play a crucial role when malaria parasites invade their host cells and during their subsequent development in hepatocytes and red blood cells. It is thought that Hsps maintain proteostasis under the unfavourable conditions that malaria parasites encounter in the host environment. Although heat shock protein 70 (Hsp70 is capable of independent folding of some proteins, its functional cooperation with heat shock protein 90 (Hsp90 facilitates folding of some proteins such as kinases and steroid hormone receptors into their fully functional forms. The cooperation of Hsp70 and Hsp90 occurs through an adaptor protein called Hsp70-Hsp90 organising protein (Hop. We previously characterised the Hop protein from Plasmodium falciparum (PfHop. We observed that the protein co-localised with the cytosol-localised chaperones, PfHsp70-1 and PfHsp90 at the blood stages of the malaria parasite. In the current study, we demonstrated that PfHop is a stress-inducible protein. We further explored the direct interaction between PfHop and PfHsp70-1 using far Western and surface plasmon resonance (SPR analyses. The interaction of the two proteins was further validated by co-immunoprecipitation studies. We observed that PfHop and PfHsp70-1 associate in the absence and presence of either ATP or ADP. However, ADP appears to promote the association of the two proteins better than ATP. In addition, we investigated the specific interaction between PfHop TPR subdomains and PfHsp70-1/ PfHsp90, using a split-GFP approach. This method allowed us to observe that TPR1 and TPR2B subdomains of PfHop bind preferentially to the C-terminus of PfHsp70-1 compared to PfHsp90. Conversely, the TPR2A motif preferentially interacted with the C-terminus of PfHsp90. Finally, we

  4. On a Hopping-Points SVD and Hough Transform-Based Line Detection Algorithm for Robot Localization and Mapping

    Directory of Open Access Journals (Sweden)

    Abhijeet Ravankar

    2016-05-01

    Full Text Available Line detection is an important problem in computer vision, graphics and autonomous robot navigation. Lines detected using a laser range sensor (LRS mounted on a robot can be used as features to build a map of the environment, and later to localize the robot in the map, in a process known as Simultaneous Localization and Mapping (SLAM. We propose an efficient algorithm for line detection from LRS data using a novel hopping-points Singular Value Decomposition (SVD and Hough transform-based algorithm, in which SVD is applied to intermittent LRS points to accelerate the algorithm. A reverse-hop mechanism ensures that the end points of the line segments are accurately extracted. Line segments extracted from the proposed algorithm are used to form a map and, subsequently, LRS data points are matched with the line segments to localize the robot. The proposed algorithm eliminates the drawbacks of point-based matching algorithms like the Iterative Closest Points (ICP algorithm, the performance of which degrades with an increasing number of points. We tested the proposed algorithm for mapping and localization in both simulated and real environments, and found it to detect lines accurately and build maps with good self-localization.

  5. EST analysis of hop glandular trichomes identifies an O-methyltransferase that catalyzes the biosynthesis of xanthohumol.

    Science.gov (United States)

    Nagel, Jana; Culley, Lana K; Lu, Yuping; Liu, Enwu; Matthews, Paul D; Stevens, Jan F; Page, Jonathan E

    2008-01-01

    The glandular trichomes (lupulin glands) of hop (Humulus lupulus) synthesize essential oils and terpenophenolic resins, including the bioactive prenylflavonoid xanthohumol. To dissect the biosynthetic processes occurring in lupulin glands, we sequenced 10,581 ESTs from four trichome-derived cDNA libraries. ESTs representing enzymes of terpenoid biosynthesis, including all of the steps of the methyl 4-erythritol phosphate pathway, were abundant in the EST data set, as were ESTs for the known type III polyketide synthases of bitter acid and xanthohumol biosynthesis. The xanthohumol biosynthetic pathway involves a key O-methylation step. Four S-adenosyl-l-methionine-dependent O-methyltransferases (OMTs) with similarity to known flavonoid-methylating enzymes were present in the EST data set. OMT1, which was the most highly expressed OMT based on EST abundance and RT-PCR analysis, performs the final reaction in xanthohumol biosynthesis by methylating desmethylxanthohumol to form xanthohumol. OMT2 accepted a broad range of substrates, including desmethylxanthohumol, but did not form xanthohumol. Mass spectrometry and proton nuclear magnetic resonance analysis showed it methylated xanthohumol to 4-O-methylxanthohumol, which is not known from hop. OMT3 was inactive with all substrates tested. The lupulin gland-specific EST data set expands the genomic resources for H. lupulus and provides further insight into the metabolic specialization of glandular trichomes.

  6. On a Hopping-points SVD and Hough Transform-based Line Detection Algorithm for Robot Localization and Mapping

    Directory of Open Access Journals (Sweden)

    Abhijeet Ravankar

    2016-05-01

    Full Text Available Line detection is an important problem in computer vision, graphics and autonomous robot navigation. Lines detected using a laser range sensor (LRS mounted on a robot can be used as features to build a map of the environment, and later to localize the robot in the map, in a process known as Simultaneous Localization and Mapping (SLAM. We propose an efficient algorithm for line detection from LRS data using a novel hopping-points Singular Value Decomposition (SVD and Hough transform-based algorithm, in which SVD is applied to intermittent LRS points to accelerate the algorithm. A reverse-hop mechanism ensures that the end points of the line segments are accurately extracted. Line segments extracted from the proposed algorithm are used to form a map and, subsequently, LRS data points are matched with the line segments to localize the robot. The proposed algorithm eliminates the drawbacks of point-based matching algorithms like the Iterative Closest Points (ICP algorithm, the performance of which degrades with an increasing number of points. We tested the proposed algorithm for mapping and localization in both simulated and real environments, and found it to detect lines accurately and build maps with good self-localization.

  7. Research on Improved DV-HOP Algorithm against Wormhole Attacks in WSN

    Directory of Open Access Journals (Sweden)

    Wang Xue-Wen

    2016-01-01

    Full Text Available The secure location of node is significant in the WSN (Wireless Sensor Networks of the troop frontier defence system. The wormhole attack is a big threat in the secure location. The credibility of the beacon node was used to determine the malicious nodes produced by wormhole attack in the WSN. The estimated method of multibeacon nodes was adopted to improve DV-HOP algorithm after excluding the malicious nodes. In this paper, we compared the basic DV-HOP algorithm and the improved DV-HOP algorithm in the coverage percentage and the error of network localization by simulating. The simulation results indicate that the improved DV-HOP algorithm makes the localization coverage percentage can reach 90% on a certain scale of the network, and it makes the error percentage lower when the number of beacons is different.

  8. You know what it is: learning words through listening to hip-hop.

    Science.gov (United States)

    Chesley, Paula

    2011-01-01

    Music listeners have difficulty correctly understanding and remembering song lyrics. However, results from the present study support the hypothesis that young adults can learn African-American English (AAE) vocabulary from listening to hip-hop music. Non-African-American participants first gave free-response definitions to AAE vocabulary items, after which they answered demographic questions as well as questions addressing their social networks, their musical preferences, and their knowledge of popular culture. Results from the survey show a positive association between the number of hip-hop artists listened to and AAE comprehension vocabulary scores. Additionally, participants were more likely to know an AAE vocabulary item if the hip-hop artists they listen to use the word in their song lyrics. Together, these results suggest that young adults can acquire vocabulary through exposure to hip-hop music, a finding relevant for research on vocabulary acquisition, the construction of adolescent and adult identities, and the adoption of lexical innovations.

  9. You know what it is: learning words through listening to hip-hop

    National Research Council Canada - National Science Library

    Chesley, Paula

    2011-01-01

    ..., their musical preferences, and their knowledge of popular culture. Results from the survey show a positive association between the number of hip-hop artists listened to and AAE comprehension vocabulary scores...

  10. You Know What It Is: Learning Words through Listening to Hip-Hop: e28248

    National Research Council Canada - National Science Library

    Paula Chesley

    2011-01-01

    ..., their musical preferences, and their knowledge of popular culture. Results from the survey show a positive association between the number of hip-hop artists listened to and AAE comprehension vocabulary scores...

  11. Spin Entangling Effects of Electron and Nucleus on Hopping Transfer in Organic Semiconductors

    Science.gov (United States)

    Zhao, Jun-Qing; Sun, Ling-Ling; Wang, Ting

    2016-05-01

    To study the spin entangling effects on organic magneto-resistance in organic semiconductors, we focused on the entanglement-related hopping transfer of electrons on the basis of the Miller-Abrahams hopping rate. Considering spin entanglement of localized electron with the nucleus in the hopping process, we deduced an attempt hopping rate of electrons as a function of the applied magnetic field and the localized hyperfine interaction, and thus established a model to calculate the organic magneto-resistance. The calculated results show that the magneto-resistance has a maximum in the lower magnetic field, and the corresponding magnetic field Bmax increases with the hyperfine interaction. In the higher magnetic field, the magneto-resistance tends to a negative saturation value. This analysis will be an valuable reference for deep understanding of the organic magneto-resistance.

  12. Multi-hop routing in wireless sensor networks an overview, taxonomy, and research challenges

    CERN Document Server

    Rani, Shalli

    2016-01-01

    This brief provides an overview of recent developments in multi-hop routing protocols for Wireless Sensor Networks (WSNs). It introduces the various classifications of routing protocols and lists the pros and cons of each category, going beyond the conceptual overview of routing classifications offered in other books. Recently many researchers have proposed numerous multi-hop routing protocols and thereby created a need for a book that provides its readers with an up-to-date road map of this research paradigm.   The authors present some of the most relevant results achieved by applying an algorithmic approach to the research on multi-hop routing protocols. The book covers measurements, experiences and lessons learned from the implementation of multi-hop communication prototypes. Furthermore, it describes future research challenges and as such serves as a useful guide for students and researchers alike.

  13. STUDY ON THE EVOLUTION OF THE HOP MARKET IN ROMANIA DURING THE PERIOD 2007-2014

    Directory of Open Access Journals (Sweden)

    Irina - Adriana CHIURCIU

    2015-06-01

    Full Text Available The aim of this article is to present the evolution of hop market during the period 2007-2014 in Romania. It is based on the statistical data provided by the National Institute of Statistics and by the Ministry of Agriculture and Rural Development. The indicators used for processing the data are the following: the total production, the cultivated areas of hop and the quantity of hop imported and exported. From the analysis of the results obtained we can observe a decrease of 69.51% in 2012 from the total production in comparison with 2007. In the last years of the period in study, from 2012 to 2014, it increased by 104.4%. However the inland production is insufficient for the local beer industry. Romania has to import vast amounts of hops to ensure the brewers requirements across the country.

  14. Interplay of radiative and nonradiative transitions in surface hopping with radiation-molecule interactions

    Energy Technology Data Exchange (ETDEWEB)

    Bajo, Juan José [Departamento de Química-Física I, Universidad Complutense de Madrid, 28040 Madrid (Spain); Granucci, Giovanni, E-mail: giovanni.granucci@unipi.it; Persico, Maurizio [Università di Pisa, Dipartimento di Chimica e Chimica Industriale, via Risorgimento 35, 56126 Pisa (Italy)

    2014-01-28

    We implemented a method for the treatment of field induced transitions in trajectory surface hopping simulations, in the framework of the local diabatization scheme, especially suited for on-the-fly dynamics. The method is applied to a simple one-dimensional model with an avoided crossing and compared with quantum wavepacket dynamics. The results show the importance of introducing a proper decoherence correction to surface hopping, in order to obtain meaningful results. Also the energy conservation policy of standard surface hopping must be revised: in fact, the quantum wavepacket energetics is well reproduced if energy absorption/emission is allowed for in the hops determined by radiation-molecule coupling. To our knowledge, this is the first time the issues of decoherence and energy conservation have been analyzed in depth to devise a mixed quantum-classical method for dynamics with molecule-field interactions.

  15. Study of one-dimensional electron hopping and its effects on ESR line shape

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Jau [Argonne National Lab., IL (United States); Dikshit, S.N. [Univ. of Chicago, IL (United States). Dept. of Chemistry; Norris, J.R. [Argonne National Lab., IL (United States)]|[Univ. of Chicago, IL (United States). Dept. of Chemistry

    1997-08-01

    Random hopping processes between discrete sites along a finite open chain or around a closed finite loop are examined. Closed form formulae are prescribed for the dependence of the ESR (electron spin resonance) line shape on the chain length and hopping rate. Significant differences between the closed loop and open chain are demonstrated. Deviation at short time from the results of diffusion in a continuum is presented.

  16. Efficient Cooperative Relaying in Wireless Multi-Hop Networks with Commodity WiFi Hardware

    OpenAIRE

    Volkhausen, Tobias; Dridger, Kornelius; Lichte, Hermann; Karl, Holger

    2012-01-01

    International audience; In wireless multi-hop networks, cooperative relaying exploits temporal and spatial diversity by additionally transmitting via a relay node and then combining direct and relay transmissions at the receiver. While such relaying improves packet error rates, it also costs an extra transmission. Along multi-hop paths, there often are nodes that can be a relay for multiple consecutive transmissions. This allows such a relay to transmit only once rather than on each individua...

  17. Optimal Partitioned Cyclic Difference Packings for Frequency Hopping and Code Synchronization

    CERN Document Server

    Chee, Yeow Meng; Yin, Jianxing

    2010-01-01

    Optimal partitioned cyclic difference packings (PCDPs) are shown to give rise to optimal frequency-hopping sequences and optimal comma-free codes. New constructions for PCDPs, based on almost difference sets and cyclic difference matrices, are given. These produce new infinite families of optimal PCDPs (and hence optimal frequency-hopping sequences and optimal comma-free codes). The existence problem for optimal PCDPs in ${\\mathbb Z}_{3m}$, with $m$ base blocks of size three, is also solved for all $m\

  18. Improved sampling and validation of frozen Gaussian approximation with surface hopping algorithm for nonadiabatic dynamics

    CERN Document Server

    Lu, Jianfeng

    2016-01-01

    In the spirit of the fewest switches surface hopping, the frozen Gaussian approximation with surface hopping (FGA-SH) method samples a path integral representation of the non-adiabatic dynamics in the semiclassical regime. An improved sampling scheme is developed in this work for FGA-SH based on birth and death branching processes. The algorithm is validated for the standard test examples of non-adiabatic dynamics.

  19. 1Gbps impulse radio ultrawideband multi-hop system employing a single mode fiber repeater

    DEFF Research Database (Denmark)

    Yu, Xianbin; Rodes, Roberto; Jensen, Jesper Bevensee;

    2009-01-01

    We experimentally demonstrate a 1 Gbps impulse radio ultrawideband multi-hop system for wireless-over-fiber applications. The system consists of two 2 m air links and a 23 km single mode fiber based optical repeater......We experimentally demonstrate a 1 Gbps impulse radio ultrawideband multi-hop system for wireless-over-fiber applications. The system consists of two 2 m air links and a 23 km single mode fiber based optical repeater...

  20. Fluctuating in the hopping rate of CuO thin films with respect to substrate temperature

    Science.gov (United States)

    Serin, N.; Yildiz, A.; Çam, E.; Uzun, Ş.; Serin, T.

    2012-10-01

    Electrical transport properties in CuO thin films processed using d.c. magnetron sputtering technique is investigated to understand the correlation between the processing conditions and electrical properties. It is identified that the temperature dependent conductivity of the investigated films is controlled by the multi-phonon hopping conduction mechanism. A detailed analysis in terms of carrier hopping parameters is used to correlate electrical transport properties with the d.c. magnetron sputtering conditions.

  1. Accelerating universes from short-range interactions

    Energy Technology Data Exchange (ETDEWEB)

    Diez-Tejedor, Alberto [Departamento de Fisica Teorica, Universidad del Pais Vasco, Apdo. 644, 48080, Bilbao (Spain)]. E-mail: wtbditea@lg.ehu.es; Feinstein, Alexander [Departamento de Fisica Teorica, Universidad del Pais Vasco, Apdo. 644, 48080, Bilbao (Spain)]. E-mail: a.feinstein@ehu.es

    2006-02-13

    We show that short-range interactions between the fundamental particles in the universe can drive a period of accelerated expansion. This description fits the early universe. In the present day universe, if one postulates short-range interactions or a sort of 'shielded gravity', the picture may repeat.

  2. Accelerating Universes from Short-Range Interactions

    CERN Document Server

    Diez-Tejedor, A; Diez-Tejedor, Alberto; Feinstein, Alexander

    2006-01-01

    We show that short-range interactions between the fundamental particles in the universe can drive a period of accelerated expansion. This description fits the early universe. In the present day universe, if one postulates short-range interactions or a sort of "shielded gravity", the picture may repeat.

  3. 'Reading' bubble chamber pictures with the Spiral Reader eyes.

    CERN Multimedia

    1974-01-01

    Interactive techniques were widely used to study bubble chamber pictures. After a visual scanning of the pictures and a vertex measurement on a Shivamatic, the Spiral Reader allowed the track polar coordinates to be easily measured. See photo 7408137X

  4. Routing protocol for wireless quantum multi-hop mesh backbone network based on partially entangled GHZ state

    Science.gov (United States)

    Xiong, Pei-Ying; Yu, Xu-Tao; Zhang, Zai-Chen; Zhan, Hai-Tao; Hua, Jing-Yu

    2017-08-01

    Quantum multi-hop teleportation is important in the field of quantum communication. In this study, we propose a quantum multi-hop communication model and a quantum routing protocol with multihop teleportation for wireless mesh backbone networks. Based on an analysis of quantum multi-hop protocols, a partially entangled Greenberger-Horne-Zeilinger (GHZ) state is selected as the quantum channel for the proposed protocol. Both quantum and classical wireless channels exist between two neighboring nodes along the route. With the proposed routing protocol, quantum information can be transmitted hop by hop from the source node to the destination node. Based on multi-hop teleportation based on the partially entangled GHZ state, a quantum route established with the minimum number of hops. The difference between our routing protocol and the classical one is that in the former, the processes used to find a quantum route and establish quantum channel entanglement occur simultaneously. The Bell state measurement results of each hop are piggybacked to quantum route finding information. This method reduces the total number of packets and the magnitude of air interface delay. The deduction of the establishment of a quantum channel between source and destination is also presented here. The final success probability of quantum multi-hop teleportation in wireless mesh backbone networks was simulated and analyzed. Our research shows that quantum multi-hop teleportation in wireless mesh backbone networks through a partially entangled GHZ state is feasible.

  5. Condom use and hip hop culture: the case of urban young men in New York City.

    Science.gov (United States)

    Muñoz-Laboy, Miguel A; Castellanos, Daniel H; Haliburton, Chanel S; del Aguila, Ernesto Vasquez; Weinstein, Hannah J; Parker, Richard G

    2008-06-01

    We explored how young men's perceptions of and participation in hip hop culture--urban social and artistic expressions, such as clothing style, breakdancing, graffiti, and rap music--and how contextual factors of the hip hop scene may be associated with their condom use, condom-use self-efficacy, and sense of community. We conducted a cross-sectional survey of 95 African American and Latino men aged 15 to 25 years as part of a 4-year ethnographic study in New York City. Differences in young men's perceptions of and levels of affiliation with hip hop culture were not statistically associated with differences in their sense of community or condom-use self-efficacy. Frequency of participation in the hip hop nightclub scene was the strongest factor negatively associated with condom use. Popular discourses on young men's health risks often blame youths' cultures such as the hip hop culture for increased risk practices but do not critically examine how risk emerges in urban young men's lives and what aspects of youths' culture can be protective. Further research needs to focus on contextual factors of risk such as the role of hip hop nightlife on increased HIV risk.

  6. HOPS: a novel cAMP-dependent shuttling protein involved in protein synthesis regulation.

    Science.gov (United States)

    Della Fazia, Maria Agnese; Castelli, Marilena; Bartoli, Daniela; Pieroni, Stefania; Pettirossi, Valentina; Piobbico, Danilo; Viola-Magni, Mariapia; Servillo, Giuseppe

    2005-07-15

    The liver has the ability to autonomously regulate growth and mass. Following partial hepatectomy, hormones, growth factors, cytokines and their coupled signal transduction pathways have been implicated in hepatocyte proliferation. To understand the mechanisms responsible for the proliferative response, we studied liver regeneration by characterization of novel genes that are activated in residual hepatocytes. A regenerating liver cDNA library screening was performed with cDNA-subtracted probes derived from regenerating and normal liver. Here, we describe the biology of Hops (for hepatocyte odd protein shuttling). HOPS is a novel shuttling protein that contains an ubiquitin-like domain, a putative NES and a proline-rich region. HOPS is rapidly exported from the nucleus and is overexpressed during liver regeneration. Evidence shows that cAMP governs HOPS export in hepatocytes of normal and regenerating liver and is mediated via CRM-1. We demonstrate that HOPS binds to elongation factor eEF-1A and interferes in protein synthesis. HOPS overexpression in H-35-hepatoma and 3T3-NIH cells strongly reduces proliferation.

  7. Hydrodynamic mean-field solutions of 1D exclusion processes with spatially varying hopping rates

    Science.gov (United States)

    Lakatos, Greg; O'Brien, John; Chou, Tom

    2006-03-01

    We analyse the open boundary partially asymmetric exclusion process with smoothly varying internal hopping rates in the infinite-size, mean-field limit. The mean-field equations for particle densities are written in terms of Ricatti equations with the steady-state current J as a parameter. These equations are solved both analytically and numerically. Upon imposing the boundary conditions set by the injection and extraction rates, the currents J are found self-consistently. We find a number of cases where analytic solutions can be found exactly or approximated. Results for J from asymptotic analyses for slowly varying hopping rates agree extremely well with those from extensive Monte Carlo simulations, suggesting that mean-field currents asymptotically approach the exact currents in the hydrodynamic limit, as the hopping rates vary slowly over the lattice. If the forward hopping rate is greater than or less than the backward hopping rate throughout the entire chain, the three standard steady-state phases are preserved. Our analysis reveals the sensitivity of the current to the relative phase between the forward and backward hopping rate functions.

  8. Random free energy barrier hopping model for ac conduction in chalcogenide glasses

    Science.gov (United States)

    Murti, Ram; Tripathi, S. K.; Goyal, Navdeep; Prakash, Satya

    2016-03-01

    The random free energy barrier hopping model is proposed to explain the ac conductivity (σac) of chalcogenide glasses. The Coulomb correlation is consistently accounted for in the polarizability and defect distribution functions and the relaxation time is augmented to include the overlapping of hopping particle wave functions. It is observed that ac and dc conduction in chalcogenides are due to same mechanism and Meyer-Neldel (MN) rule is the consequence of temperature dependence of hopping barriers. The exponential parameter s is calculated and it is found that s is subjected to sample preparation and measurement conditions and its value can be less than or greater than one. The calculated results for a - Se, As2S3, As2Se3 and As2Te3 are found in close agreement with the experimental data. The bipolaron and single polaron hopping contributions dominates at lower and higher temperatures respectively and in addition to high energy optical phonons, low energy optical and high energy acoustic phonons also contribute to the hopping process. The variations of hopping distance with temperature is also studied. The estimated defect number density and static barrier heights are compared with other existing calculations.

  9. Hydrodynamic mean-field solutions of 1D exclusion processes with spatially varying hopping rates

    Energy Technology Data Exchange (ETDEWEB)

    Lakatos, Greg; O' Brien, John; Chou, Tom [Department of Biomathematics and Institute for Pure and Applied Mathematics, UCLA, Los Angeles, CA 90095 (United States)

    2006-03-10

    We analyse the open boundary partially asymmetric exclusion process with smoothly varying internal hopping rates in the infinite-size, mean-field limit. The mean-field equations for particle densities are written in terms of Ricatti equations with the steady-state current J as a parameter. These equations are solved both analytically and numerically. Upon imposing the boundary conditions set by the injection and extraction rates, the currents J are found self-consistently. We find a number of cases where analytic solutions can be found exactly or approximated. Results for J from asymptotic analyses for slowly varying hopping rates agree extremely well with those from extensive Monte Carlo simulations, suggesting that mean-field currents asymptotically approach the exact currents in the hydrodynamic limit, as the hopping rates vary slowly over the lattice. If the forward hopping rate is greater than or less than the backward hopping rate throughout the entire chain, the three standard steady-state phases are preserved. Our analysis reveals the sensitivity of the current to the relative phase between the forward and backward hopping rate functions.

  10. PPG: online generation of protein pictures and animations.

    Science.gov (United States)

    Binisti, Cédric; Salim, Ahmed Ali; Tufféry, Pierre

    2005-07-01

    The protein picture generator (PPG) is an online service to generate pictures of a protein structure. Its design was conceived as an answer to the need expressed by a part of the community to have some means to produce simply complex pictures to insert in publications or in presentations. PPG can produce static or animated pictures. It can be accessed at http://bioserv.rpbs.jussieu.fr/cgi-bin/PPG.

  11. Adaptive time steps in trajectory surface hopping simulations

    Science.gov (United States)

    Spörkel, Lasse; Thiel, Walter

    2016-05-01

    Trajectory surface hopping (TSH) simulations are often performed in combination with active-space multi-reference configuration interaction (MRCI) treatments. Technical problems may arise in such simulations if active and inactive orbitals strongly mix and switch in some particular regions. We propose to use adaptive time steps when such regions are encountered in TSH simulations. For this purpose, we present a computational protocol that is easy to implement and increases the computational effort only in the critical regions. We test this procedure through TSH simulations of a GFP chromophore model (OHBI) and a light-driven rotary molecular motor (F-NAIBP) on semiempirical MRCI potential energy surfaces, by comparing the results from simulations with adaptive time steps to analogous ones with constant time steps. For both test molecules, the number of successful trajectories without technical failures rises significantly, from 53% to 95% for OHBI and from 25% to 96% for F-NAIBP. The computed excited-state lifetime remains essentially the same for OHBI and increases somewhat for F-NAIBP, and there is almost no change in the computed quantum efficiency for internal rotation in F-NAIBP. We recommend the general use of adaptive time steps in TSH simulations with active-space CI methods because this will help to avoid technical problems, increase the overall efficiency and robustness of the simulations, and allow for a more complete sampling.

  12. Characteristics of alternating current hopping conductivity in DNA sequences

    Institute of Scientific and Technical Information of China (English)

    Ma Song-Shan; Xu Hui; Wang Huan-You; Guo Rui

    2009-01-01

    This paper presents a model to describe alternating current (AC) conductivity of DNA sequences,in which DNA is considered as a one-dimensional (1D) disordered system,and electrons transport via hopping between localized states.It finds that AC conductivity in DNA sequences increases as the frequency of the external electric field rises,and it takes the form of σac(ω)~ω2 ln2(1/ω).Also AC conductivity of DNA sequences increases with the increase of temperature,this phenomenon presents characteristics of weak temperature-dependence.Meanwhile,the AC conductivity in an off diagonally correlated case is much larger than that in the uncorrelated case of the Anderson limit in low temperatures,which indicates that the off-diagonal correlations in DNA sequences have a great effect on the AC conductivity,while at high temperature the off-diagonal correlations no longer play a vital role in electric transport. In addition,the proportion of nucleotide pairs p also plays an important role in AC electron transport of DNA sequences.For p<0.5,the conductivity of DNA sequence decreases with the increase of p,while for p > 0.5,the conductivity increases with the increase of p.

  13. Harvard Observing Project (HOP): Involving Undergraduates in Research Projects

    Science.gov (United States)

    Bieryla, Allyson

    2017-01-01

    The Harvard Observing Project (HOP) is designed to get students excited about observational astronomy while collecting data valuable to the scientific community. The primary goal is to give undergraduates a chance to try out observing with “no strings attached”. Observations are led by experienced observers, mostly graduate students. This not only gives graduate students extra opportunities to interact and teach undergraduates, but also a chance for them to get more observing experience. Each semester, we choose an interesting target and monitor it each week over the course of the semester using Harvard University’s 16-inch DFM Clay Telescope. These observing projects often produce large amounts of data. This provides an excellent dataset for a young undergraduate to analyze. Some successful semester-long observing projects have included variable stars, supernova and binary systems. Short-term projects have included exoplanet candidate followup, asteroid and comet followup and collaborating with the Pro-Am White Dwarf Monitoring (PAWM) project in attempts to detect a transiting Earth-sized planet orbiting a white dwarf. Each dataset is an opportunity for an undergraduate to be introduced to scientific research and present the results to the community.

  14. Impulsive movements lead to high hops on sand

    Science.gov (United States)

    Aguilar, Jeffrey; Goldman, Daniel I.

    2014-03-01

    Various animals exhibit locomotive behaviors (like sprinting and hopping) involving transient bursts of actuation coupled to the ground through internal elastic elements. The performance of such maneuvers is subject to reaction forces on the feet from the environment. On substrates like dry granular media, the laws that govern these forces are not fully understood, and can vary with foot size and shape, material compaction (measured by the volume fraction ϕ) and intrusion kinematics. To gain insight into how such interactions affect jumps on granular media, we study the performance of an actuated spring mass robot. We compare performance between two jump strategies: a single-cycle sine-wave actuation (a ``single jump'') and this actuation preceded by an impulsive preload (a ``preload jump''). We vary ϕ for both strategies, and find that ϕ significantly affects performance: we observe a 200% increase in the single jump height with only a 5% increase in volume fraction using a 7.62 cm diameter flat foot. The preload jump outperforms the single jump height by 150% for all ϕ. We hypothesize that this increase in performance results from higher intrusion velocities and accelerations associated with the preload. NSF POLS CAREER, Burroughs Wellcome Fund, and ARO.

  15. SDN-based path hopping communication against eavesdropping attack

    Science.gov (United States)

    Zhang, Chuanhao; Bu, Youjun; Zhao, Zheng

    2016-10-01

    Network eavesdropping is one of the most popular means used by cyber attackers, which has been a severe threat to network communication security. Adversaries could capture and analyze network communication data from network nodes or links, monitor network status and steal sensitive data such as username and password etc. Traditional network usually uses static network configuration, and existing defense methods, including firewall, IDS, IPS etc., cannot prevent eavesdropping, which has no distinguishing characteristic. Network eavesdropping become silent during most of the time of the attacking process, which is why it is difficult to discover and to defend. But A successful eavesdropping attack also has its' precondition, which is the target path should be relatively stable and has enough time of duration. So, In order to resolve this problem, it has to work on the network architecture. In this paper, a path hopping communication(PHC) mechanism based on Software Define Network (SDN) was proposed to solve this problem. In PHC, Ends in communication packets as well as the routing paths were changed dynamically. Therefore, the traffic would be distributed to multiple flows and transmitted along different paths. so that Network eavesdropping attack could be prevented effectively. It was concluded that PHC was able to increase the overhead of Network eavesdropping, as well as the difficulty of communication data recovery.

  16. Power and delay optimisation in multi-hop wireless networks

    KAUST Repository

    Xia, Li

    2014-02-05

    In this paper, we study the optimisation problem of transmission power and delay in a multi-hop wireless network consisting of multiple nodes. The goal is to determine the optimal policy of transmission rates at various buffer and channel states in order to minimise the power consumption and the queueing delay of the whole network. With the assumptions of interference-free links and independently and identically distributed (i.i.d.) channel states, we formulate this problem using a semi-open Jackson network model for data transmission and a Markov model for channel states transition. We derive a difference equation of the system performance under any two different policies. The necessary and sufficient condition of optimal policy is obtained. We also prove that the system performance is monotonic with respect to (w.r.t.) the transmission rate and the optimal transmission rate can be either maximal or minimal. That is, the ‘bang-bang’ control is an optimal control. This optimality structure greatly reduces the problem complexity. Furthermore, we develop an iterative algorithm to find the optimal solution. Finally, we conduct the simulation experiments to demonstrate the effectiveness of our approach. We hope our work can shed some insights on solving this complicated optimisation problem.

  17. Reliability and Feedback of Multiple Hop Wireless Networks

    Institute of Scientific and Technical Information of China (English)

    N. Eva Wu; Sudha Thavamani; Xiaohua Li

    2007-01-01

    This paper analyzes fault-tolerance over the entire design life of a class of multiple-hop wireless networks, where cooperative transmission schemes are used. The networks are subject to both node failure and random channel fading. A node lifetime distribution is modeled with an increasing failure rate, where the node power consumption level enters the parameters of the distribution. A method for assessing both link and network reliabilities projected at the network's design life is developed. Link reliability is enhanced through use of redundant nodes. The number of redundant nodes is restricted by the cooperative transmission scheme used.The link reliability is then used to establish a re-transmission control policy that minimizes an expected cost involving power, bandwidth expenditures, and packet loss. The benefit and cost of feedback in network operations are examined. The results of a simulation study under specific node processing times are presented. The study quantifies the effect of loop closure frequency, acknowledgment deadline, and nodes' storage capacity on the performance of the network in terms of network lifetime, packet loss rate, and false alarm rate. The study concludes that in a network where energy is severely constrained, feedback must be applied judiciously.

  18. Scaffold hopping approach on the route to selective tankyrase inhibitors.

    Science.gov (United States)

    Liscio, Paride; Carotti, Andrea; Asciutti, Stefania; Ferri, Martina; Pires, Maira M; Valloscuro, Sara; Ziff, Jacob; Clark, Neil R; Macchiarulo, Antonio; Aaronson, Stuart A; Pellicciari, Roberto; Camaioni, Emidio

    2014-11-24

    A virtual screening procedure was applied to identify new tankyrase inhibitors. Through pharmacophore screening of a compounds collection from the SPECS database, the methoxy[l]benzothieno[2,3-c]quinolin-6(5H)-one scaffold was identified as nicotinamide mimetic able to inhibit tankyrase activity at low micromolar concentration. In order to improve potency and selectivity, tandem structure-based and scaffold hopping approaches were carried out over the new scaffold leading to the discovery of the 2-(phenyl)-3H-benzo[4,5]thieno[3,2-d]pyrimidin-4-one as powerful chemotype suitable for tankyrase inhibition. The best compound 2-(4-tert-butyl-phenyl)-3H-benzo[4,5]thieno[3,2-d]pyrimidin-4-one (23) displayed nanomolar potencies (IC50s TNKS-1 = 21 nM and TNKS-2 = 29 nM) and high selectivity when profiled against several other PARPs. Furthermore, a striking Wnt signaling, as well as cell growth inhibition, was observed assaying 23 in DLD-1 cancer cells.

  19. Detecting Sinkhole Attacks in Wireless Sensor Network using Hop Count

    Directory of Open Access Journals (Sweden)

    Md. Ibrahim Abdullah

    2015-02-01

    Full Text Available Nowadays, Wireless Sensor Networks (WSNs are widely used in many areas, especially in environment applications, military applications, queue tracking, etc. WSNs are vulnerable to different types of security attacks due to various constraints such as broadcasted nature of transmission medium, deployment in open or hostile environment where they are not physically protected, less memory, and limited battery power. So, security system is the crucial requirements of these networks. One of the most notably routing attacks is the sinkhole attack where an adversary captures or insert nodes in the sensor field that advertise high quality routes to the base station. In this paper, a mechanism is proposed against sinkhole attacks which detect malicious nodes using hop counting. The main advantage of the proposed technique is that, a node can detects malicious nodes only collaborating with the neighbor nodes without requiring any negotiation with the base station. Simulation result shows that, the proposed technique successfully detects the sinkhole nodes for large sensor field.

  20. El griot no ha muerto, viva el hip-hop

    Directory of Open Access Journals (Sweden)

    Fco. Javier González García-Mamely

    2015-11-01

    Full Text Available La oratura en África ha jugado un papel vital a lo largo de los milenios como un (único medio de preservar y transmitir la historia, la cultura y el imaginario de cada comunidad. El griot es un claro modelo de las artes orales, pero ha sufrido cambios drásticos en su modo de vida y en los recursos narrativos de los que dispone. Tras el mecenazgo de los grandes reyes y las sucesivas llegadas del islam, el colonialismo y los procesos de modernización y occidentalización, los griots se han tenido que adaptar a nuevos patrones, audiencias y medios de comunicación, convirtiéndose en políticos o en figuras del espectáculo. La aparición del rap y el hip-hop reclamando ser los “modernos griots” ha ocasionado una respuesta crítica y una atracción viral hacia el nuevo fenómeno, sea éste un nuevo género o una reinvención de la oratura del antiguo griot.

  1. Two-hop Secure Communication Using an Untrusted Relay

    CERN Document Server

    He, Xiang

    2009-01-01

    We consider a source-destination pair that can only communicate through an untrusted intermediate relay node. The intermediate node is willing to employ a designated relaying scheme to facilitate reliable communication between the source and the destination. Yet, the information it relays needs to be kept secret from it. In this two-hop communication scenario, where the use of the untrusted relay node is essential, we find that a positive secrecy rate is achievable. The center piece of the achievability scheme is the help provided by either the destination node with transmission capability, or an external "good samaritan" node. In either case, the helper performs cooperative jamming that confuses the eavesdropping relay and disables it from being able to decipher what it is relaying. We next derive an upper bound on the secrecy rate for this system. We observe that the gap between the upper bound and the achievable rate vanishes as the power of the relay node goes to infinity. Overall, the paper presents a ca...

  2. 21 CFR 892.2050 - Picture archiving and communications system.

    Science.gov (United States)

    2010-04-01

    ... Group (JPEG) Std., Society of Motion Picture and Television Engineers (SMPTE) Test Pattern). ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Picture archiving and communications system. 892... SERVICES (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.2050 Picture archiving...

  3. Problems Brought about by "Reading" a Sequence of Pictures.

    Science.gov (United States)

    Bornens, Marie-Therese

    1990-01-01

    A study investigated 4 problems of children between 3 and 7.5 years of age: difficulty in seeing the same character in different representations; the process of linking several pictures into 1 story; the correlation between the temporal order and spatial disposition of pictures; and the tendency to consider the setting of pictures as a puzzle to…

  4. 78 FR 51064 - Safety Zone; Motion Picture Production; Chicago, IL

    Science.gov (United States)

    2013-08-20

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Motion Picture Production; Chicago, IL... from portions of Chicago waterways due to the filming of a motion picture. These temporary safety zones... work, low-flying helicopter, and other hazards involved in the filming of a motion picture. DATES:...

  5. 29 CFR 541.709 - Motion picture producing industry.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 3 2010-07-01 2010-07-01 false Motion picture producing industry. 541.709 Section 541.709... SALES EMPLOYEES Definitions and Miscellaneous Provisions § 541.709 Motion picture producing industry... motion picture producing industry who is compensated at a base rate of at least $695 a week (exclusive...

  6. 50 CFR 27.71 - Motion or sound pictures.

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false Motion or sound pictures. 27.71 Section 27.71 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF THE INTERIOR... Equipment § 27.71 Motion or sound pictures. The taking or filming of any motion or sound pictures on...

  7. 78 FR 57570 - Safety Zone; Motion Picture Production; Chicago, Illinois

    Science.gov (United States)

    2013-09-19

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Motion Picture Production; Chicago... will enforce the temporary safety zone for motion picture filming in Calumet Harbor, Chicago, IL from 9... intended to ensure safety of life on navigable waters during nighttime filming of a motion picture...

  8. Developing a molecular picture for polymer glasses under large deformation

    Science.gov (United States)

    Wang, Shi-Qing; Cheng, Shiwang; Wang, Panpan

    2014-03-01

    Polymer glasses differ from most other types of glassy materials because they can be ductile under tensile extension. Remarkably, a ductile polymer can turn brittle and vice versa. For example, upon cooling, the glass changes from ductile to brittle at a temperature known as the brittle-ductile transition temperature (BDT). Aging causes the ductile glass to be brittle. Mechanical ``rejuvenation'' or pressurization brings a brittle glass into a ductile state. Finally, one glass can be ductile 100 degrees below Tg while another polymer is already brittle even just 10 degree below Tg. Polystyrene and bisphenol A polycarbonate are at the two extremes in the family of polymer glasses. How to rationale such a wide range of behavior in terms of a molecular picture has been a challenging task. What is the role of ``chain entanglement''? Since many of the procedures including the temperature change do not alter the ``chain entanglement'', it is clearly insufficient to explain the nature of the BDT in terms of the entanglement density. Our work attempts to answer the question of what then is the role of chain networking. We have formulated a molecular picture that presents a unifying and coherent explanation for all the known phenomenology concerning the BDT and condition for crazing. This work is supported, in part, by NSF (CMMI-0926522 and DMR-1105135).

  9. Enzyme kinetics: the whole picture reveals hidden meanings.

    Science.gov (United States)

    Pinto, Maria F; Estevinho, Berta N; Crespo, Rosa; Rocha, Fernando A; Damas, Ana M; Martins, Pedro M

    2015-06-01

    The methodology adopted by Michaelis and Menten in 1913 is still routinely used to characterize the catalytic power and selectivity of enzymes. These kinetic measurements must be performed soon after the purified enzyme is mixed with a large excess of substrate. Other time scales and solution compositions are no less physiologically relevant, but fall outside the range of applicability of the classical formalism. Here we show that the complete picture of an enzyme's mode of function is critically obscured by the limited scope of conventional kinetic analysis, even in the simplest case of a single active site without inhibition. This picture is now unveiled in a mathematically closed form that remains valid over the reaction time for all combinations of enzyme/substrate concentrations and rate constants. Algebraic simplicity is maintained in the new formalism when stationary reaction phases are considered. By achieving this century-old objective, the otherwise hidden role of the reversible binding step is revealed and atypical kinetic profiles are explained. Most singular kinetic behaviors are identified in a critical region of conditions that coincide with typical cell conditions. Because it is not covered by the Michaelis-Menten model, the critical region has been missed until now by low- and high-throughput screenings of new drugs. New possibilities are therefore raised for novel and once-promising inhibitors to therapeutically target enzymes.

  10. MISTY PICTURE EVENT, Test Execution Report

    Science.gov (United States)

    1987-11-30

    Prather, oD ()Civ Photo Technologist MSgt Michael Yoas. USAF TRS NCO SSgt Danny Burns, USAF Administration NCO SSgt Ernesto Tagle , USAF Administration...I1 ARMTE J. Briones Evaluateý and cover 1365 E. Dunlap and 1371’. LANL J. Ylverton S-12 ARMTE R. Gomez Evaluate 1315, 1325 and 0. Melton secure SF3 1...PICTURE Observation Point. SITE TRAILER AGENCY FUNCTION NAME Admin Park Test Control DNA Test Control MAJ Walls CPT(P) Sauer SSgt Tagle SSgt Burns CDR Lund

  11. Java EE 7 the big picture

    CERN Document Server

    Coward, Danny

    2015-01-01

    Java EE 7: The Big Picture uniquely explores the entire Java EE 7 platform in an all-encompassing style while examining each tier of the platform in enough detail so that you can select the right technologies for specific project needs. In this authoritative guide, Java expert Danny Coward walks you through the code, applications, and frameworks that power the platform. Take full advantage of the robust capabilities of Java EE 7, increase your productivity, and meet enterprise demands with help from this Oracle Press resource.

  12. Picturing diversity in the ATLAS collaboration

    CERN Document Server

    Biondi, Silvia; The ATLAS collaboration

    2017-01-01

    With over 3000 members from 178 institutes, the ATLAS Collaboration is naturally diverse. However, capturing this diversity through pictures can be a challenge. Photography is a powerful tool, allowing us to reveal the faces behind a story and give the public the unique opportunity to understand and appreciate the human aspects of ATLAS's scientific research. The role of photographs in portraying the diversity of the ATLAS Collaboration and on various communication platforms will be described. Their impact will be examined, with focus on engagement of new audiences.

  13. Picturing diversity in the ATLAS experiment.

    CERN Document Server

    Biondi, Silvia; The ATLAS collaboration

    2017-01-01

    With over 3,000 members from 178 institutes, the ATLAS Collaboration is naturally diverse. However, capturing this diversity through pictures can be a challenge. Photography is a powerful tool, allowing us to reveal the faces behind a story and give the public the unique opportunity to understand and appreciate the human aspects of ATLAS’s scientific research. The role of photographs in portraying the diversity of the ATLAS Collaboration will be described. Their role on various communication platforms will be described and their impact examined, with focus on engagement of new audiences.

  14. Dwarfism and gigantism in historical picture postcards.

    Science.gov (United States)

    Enderle, A

    1998-05-01

    A collection of 893 historical picture postcards from 1900 to 1935, depicting dwarfs and giants, was analysed from medical and psychosocial viewpoints. In conditions such as 'bird headed dwarfism', achondroplasia, cretinism, so-called Aztecs or pinheads, Grebe chondrodysplasia, and acromegalic gigantism, the disorder could be diagnosed easily. In hypopituitary dwarfism, exact diagnosis was more difficult because of heterogeneity. The most common conditions depicted were pituitary dwarfism and achondroplasia. Most of those with gigantism had pituitary gigantism and acromegaly. Brothers and sisters or parents and their children provided evidence of mendelian inheritance of some of these disorders. The cards suggest that being put on show provided, at least in some cases, social benefits.

  15. Principles for a Unified Picture of Fermions

    CERN Document Server

    Nishimura, Kimihide

    2012-01-01

    The principles and conceptual foundations required for a unified picture of fermions are clarified, which in turn suggest that the standard theory may be reducible in a far simpler form. The resultant three generation model describes quarks and leptons as quasi excitations of a single chiral doublet, while electromagnetic and strong interactions as secondary interactions mediated by Nambu-Goldstone bosons originated from spontaneous violations of global SU(2) and Lorentz symmetries. The model also provides an alternative scenario for baryon and lepton asymmetries of the Universe.

  16. Brassinosteroid signal transduction: An emerging picture

    Institute of Scientific and Technical Information of China (English)

    WANG Qiaomei; MA Ligeng

    2003-01-01

    Steroid hormones play essential roles in animal growth and development. Steroid signaling in animal system is focused on the direct gene regulation response mediated by its nuclear receptors. Recently, steroid hormones are also found in plants. Identification of BRI1 - a critical component of the plasma-membrane steroid receptor complex, and the related signal transduction pathway mediated by the membrane receptor have revealed an elementary picture of BR signaling from the cell surface perception to the activation of BR-responsive nuclear genes.

  17. Venus in motion. [Mariner 10 television pictures

    Science.gov (United States)

    Anderson, J. L.; Danielson, G. E.; Evans, N.; Soha, J. M.; Belton, M. J. S.

    1978-01-01

    A comprehensive set of television pictures of Venus taken by the Mariner 10 spacecraft is presented. Included is a chronological sequence of television images illustrating the development, variety, and circulation of Venus upper-atmospheric phenomena as viewed in the near-ultraviolet. The higher-resolution images have been assembled into global mosaics to facilitate comparison. Figures and tables describing the imaging sequences have been included to provide a guide to the more complete set of 3400 Venus images on file at the National Space Science Data Center.

  18. Spin-catalyzed hopping conductivity in disordered strongly interacting quantum wires

    Science.gov (United States)

    Parameswaran, S. A.; Gopalakrishnan, S.

    2017-01-01

    In one-dimensional electronic systems with strong repulsive interactions, charge excitations propagate much faster than spin excitations. Such systems therefore have an intermediate temperature range [termed the "spin-incoherent Luttinger liquid" (SILL) regime] where charge excitations are "cold" (i.e., have low entropy) whereas spin excitations are "hot." We explore the effects of charge-sector disorder in the SILL regime in the absence of external sources of equilibration. We argue that the disorder localizes all charge-sector excitations; however, spin excitations are protected against full localization, and act as a heat bath facilitating charge and energy transport on asymptotically long time scales. The charge, spin, and energy conductivities are widely separated from one another. The dominant carriers of energy in much of the SILL regime are neither charge nor spin excitations, but neutral "phonon" modes, which undergo an unconventional form of hopping transport that we discuss. We comment on the applicability of these ideas to experiments and numerical simulations.

  19. Sparse Channel Estimation for Dual-Hop Amplify-and-Forward Cooperative Communiacion Systems

    Directory of Open Access Journals (Sweden)

    Guan Gui

    2013-01-01

    Full Text Available Cooperative transmission is one of key techniques which can improve system capacity and transmit range with limit power in the next-generation communication systems. However, accurate Channel State Information (CSI is necessary at the destination for coherent detection. Consider a Dual-Hop Amplify-and-Forward (DHAF Cooperative Communication System (CCS, traditional linear channel estimation method, e.g., Least Square (LS, based assumption of the rich multipath cascaded channel, is robust and simple while at the cost of low spectrum efficiency. Recent channel measurements have shown that the wireless channel exhibits great sparse in some highdimensional space. In this study, we confirmed that cascaded channel exhibits sparse distribution if the two individual channels are sparse by using representative simulation results. Later, we propose an efficient sparse channel estimation method to take advantage of the inherent sparse prior information in DHAF CCS. Simulation results confirm the superiority of our proposed methods over LS-based linear channel estimation method.

  20. Tailoring Rydberg interactions via F\\"orster resonances: state combinations, hopping and angular dependence

    CERN Document Server

    Paris-Mandoki, Asaf; Tresp, Christoph; Mirgorodskiy, Ivan; Hofferberth, Sebastian

    2016-01-01

    F\\"orster resonances provide a highly flexible tool to tune both the strength and the angular shape of interactions between two Rydberg atoms. We give a detailed explanation about how F\\"orster resonances can be found by searching through a large range of possible quantum number combinations. We apply our search method to $SS$, $SD$ and $DD$ pair states of $^{87}$Rb with principal quantum numbers from 30 to 100, taking into account the fine structure splitting of the Rydberg states. We find various strong resonances between atoms with a large difference in principal quantum numbers. We quantify the strength of these resonances by introducing a figure of merit $\\tilde C_3$ which is independent of the magnetic quantum number and geometry to classify the resonances by interaction strength. We further predict to what extent interaction exchange is possible on different resonances and point out limitations of the coherent hopping process. Finally, we discuss the angular dependence of the dipole-dipole interaction ...