A high-accuracy extraction of the isoscalar πN scattering length from pionic deuterium data

International Nuclear Information System (INIS)

Phillips, Daniel R.; Baru, Vadim; Hanhart, Christoph; Nogga, Andreas; Hoferichter, Martin; Kubis, Bastian

2010-01-01

We present a high-accuracy calculation of the π(bar sign)d scattering length using chiral perturbation theory up to order (M π /m p ) 7/2 . For the first time isospin-violating corrections are included consistently. The resulting value of a π -bar d has a theoretical uncertainty of a few percent. We use it, together with data on pionic deuterium and pionic hydrogen atoms, to extract the isoscalar and isovector pion-nucleon scattering lengths from a combined analysis, and obtain a + (7.9±3.2)·10 -3 M π -1 and a-bar (86.3±1.0)·10 -3 M π -1 .

The quadrupole moment and strong interaction parameters from muonic and pionic X-ray studies of 237Np

International Nuclear Information System (INIS)

Laat, C.T.A.M. de; Taal, A.; Duinker, W.; Konijn, J.; Petitjean, C.; Reist, H.W.; Mueller, W.; Commission of the European Communities, Geel

1987-01-01

The X-ray spectrum of muonic and pionic 237 Np has been investigated with muons and pions stopped in a NpO 2 target. The nuclear spectroscopic quadrupole moment was determined to be Q=3.886±0.006 b from the splittings of the muonic 5g→4f hyperfine complexes. The B(E2)↓-values for the first and second excited states were evaluated as 3.17±0.08 and 2.77±0.10 e 2 b 2 , respectively. A comparison between the muonic and pionic 5g→4f hyperfine complexes yields the strong interaction parameter for the pionic 4f state. For the first time a change of sign as function of Z for the strong interaction quadrupole shift ε 2 (4f) has been observed. The standard optical model predictions agree reasonably well with the measured strong interaction monopole shift, ε 0 (4f), and width, Γ 0 (4f), while they disagree with the experimental value for ε 2 . A stronger s-wave repulsion in the optical potential could explain this effect. (orig.)

High-precision measurement of strong-interaction effects in pionic deuterium

Energy Technology Data Exchange (ETDEWEB)

Strauch, Thomas

2009-06-30

The hadronic ground state shift {epsilon}{sub 1s} and width {gamma}{sub 1s} in pionic deuterium were measured with high precision at the pion factory of the Paul Scherrer Institut (PSI), Switzerland (PSI-Experiment R-06.03). In this experiment the {pi}D(3p-1s) X-ray transition of about 3 keV was measured using a high-resolution Bragg crystal spectrometer equipped with a large-area position sensitive CCD detector. The characteristic X-radiation stems from a de-excitation cascade of the pionic atom. In order to produce an intense X-ray source, the cyclotron trap was used to stop pions in a cryogenic D{sub 2} target after winding up the pion beam in a magnetic field. The hadronic shift {epsilon}{sub 1s} is obtained from the measured transition energy by comparison to the pure electromagnetic value, where the determination of the broadening {gamma}{sub 1s} requires the precise knowledge of the spectrometer response, obtained from measurements of narrow X-ray transitions from highly ionised atoms, produced in an electron cyclotron resonance ion trap. As the formation rate is assumed to be density dependent, the {pi}D(3p-1s) X-ray energy was measured at three different D{sub 2} pressures. Another cascade process (Coulomb de-excitation) transforms the energy release of de-excitation steps into kinetic energy of the collision partners leading to a Doppler broadening of subsequent X-ray transitions. The hadronic broadening {gamma}{sub 1s} is only obtained after deconvolution of the spectrometer response function and the contributions from Doppler broadening. No energy dependence of the {pi}D(3p-1s) was found, and it is concluded that radiative de-excitation from molecular states is negligible within the experimental accuracy. Hence, the result for the shift reads {epsilon}{sub 1s} = (-2.325{+-}0.031) eV, corresponding to an accuracy of 1.3% and represents the average of the three measured densities. The uncertainty is dominated by the accuracy of the gallium K{alpha}{sub 2

Evidence of central repulsion potential from pionic decay of s-shell Λ-hypernuclei

International Nuclear Information System (INIS)

Kumagai-Fuse, I.; Okabe, S.; Akaishi, Y.

1994-10-01

Pionic decays of A=4 and 5 hypernuclei are discussed to obtain information about a nucleus-Λ potential. Results for the available decay widths support as a whole that the nucleus-Λ potential has central repulsion not only in A=5 but also in A=4 hypernuclei. (author)

Experimental determination of the relativistic fine structure splitting in a pionic atom

International Nuclear Information System (INIS)

Wang, K.-C.; Boehm, F.; Hahn, A.A.; Henrikson, H.E.; Miller, J.P.; Powers, R.J.; Vogel, P.; Vuilleumier, J.-L.; Kunselman, R.

1978-01-01

Using a high-resolution crystal spectrometer, the authors have measured the energy splitting of the pionic 5g-4f and 5f-4d transitions in Ti. The observed fine structure splitting agrees, within the experimental error of 3%, with the splitting arising from the calculated relativistic term and other small corrections for spinless particles. (Auth.)

Pionic 4f-3d X-rays from 208Pb and 209Bi

International Nuclear Information System (INIS)

Olin, A.; Forsman, J.W.; MacDonald, J.A.; Marshall, G.M.; Numao, T.; Poffenberger, P.R.; Van Esbroek, P.; Kunselman, A.R.; Olaniyi, B.H.

1985-01-01

The X-ray energies and widths of the pionic 4f-3d and 5g-4f transitions have been measured in 208 Pb and 209 Bi. The 3d widths obtained are in reasonable agreement with theory, and do not support the anomalously small values previously reported. (orig.)

Pionic annihilation of antiprotons stopped on 3He

International Nuclear Information System (INIS)

Bendiscioli, G.; Filippini, V.; Rotondi, A.; Salvini, P.; Venaglioni, A.; Bossolasco, S.; Bussa, M.P.; Busso, L.; Fava, L.; Ferrero, L.; Maggiora, A.; Panzieri, D.; Piragino, G.; Piragino, R.; Tosello, F.; Batusov, Yu.A.; Falomkin, I.V.; Pontecorvo, G.B.; Rozhdestvensky, A.M.; Sapozhnikov, M.G.; Tretyak, V.I.; Guaraldo, C.; Haatuft, A.; Halsteinslid, A.; Myklebost, K.; Olsen, J.M.; Zenoni, A.

1990-01-01

The pionic annihilation of antiprotons stopped on 3 He nuclei in a self-shunted streamer chamber exposed to the antiproton beam of LEAR is studied. The data concern charged-particle multiplicity distributions, branching ratios for different final states, the probability of final-state interaction, π - , π + , p and d momentum spectra, like and unlike pion angular correlations, π and other charged-particle angular correlations. The comparison of the 3 He data with those obtained on 1 H, 2 H and 4 He does not reveal relevant effects due to the increase of the nucleon number; the small differences can be seen as due to a weak final-state interaction. (orig.)

Electric quadrupole moments and strong interaction effects in pionic atoms of 165Ho, 175Lu, 176Lu, 179Hf and 181Ta

International Nuclear Information System (INIS)

Olaniyi, B.; Shor, A.; Cheng, S.C.; Dugan, G.; Wu, C.S.

1981-05-01

The effective quadrupole moments Q sub(eff) of the nuclei of 165 Ho, 175 Lu, 176 Lu, 179 Hf and 181 Ta were accurately measured by detecting the pionic atom 5g-4f x-rays of the elements. The spectroscopic quadrupole moments, Q sub(spec), were obtained by correcting Q sub(eff) for nuclear finite size effect, distortion of the pion wave function by the pion-nucleus strong interaction, and contribution to the energy level splittings by the strong interaction. The intrinsic quadrupole moments, Q 0 , were obtained by projecting Q sub(spec) into the frame of reference fixed on the nucleus. The shift, epsilon 0 , and broadening, GAMMA 0 , of the 4f energy level due to the strong interactions between the pion and the nucleons for all the elements were also measured. Theoretical values of epsilon 0 and GAMMA 0 were calculated and compared to the experimental values. The measured values of Q 0 were compared with the existing results in muonic and pionic atoms. The measured values of epsilon 0 and GAMMA 0 were also compared with existing values. (auth)

Pion-transfer (n,d) and (d, 3He) reactions leading to deeply bound pionic atoms

International Nuclear Information System (INIS)

Toki, H.; Hirenzaki, S.; Yamazaki, T.

1990-11-01

Theoretical studies are given on the (n,d) and (d, 3 He) reactions leading to deeply bound pionic atoms in heavy nuclei of configuration [(nl) π ·j n -1 ]J. The cross sections for various pionic and neutron-hole configurations in the case of a 208 Pb target are calculated at incident energies 300-1000 MeV/u by using the effective number approach and the eikonal approximation for distortion. The effective number with a pion in the 1s or 2p state and a neutron hole in the i 13/2 orbit peaks around the same incident energy (T n =600 MeV) as the elementary cross section n+n→d+π - , where the momentum transfer matches the angular-momentum transfer of L=5∼7. The DWIA cross section for (n,d) producing a pion in the 1s or 2p orbit at T n =600 MeV is found to be around 42 or 75 μb/sr, respectively. At T n =350 MeV, where the momentum transfer is small, quasi-substitutional states of configurations [(2p) π (3p 1/2 ) n -1 ]L=0 and [(2p) π (3p 3/2 ) n -1 ]L=0 are preferentially populated with cross sections of 190 and 380 μb/sr, respectively. The (d, 3 He) cross sections are estimated to be an order of magnitude smaller than the (n,d) cross sections. Thus, the (n,d) and (d, 3 He) reactions are found to be suited for the production of deeply bound pionic atoms. (author)

Pionic atom as a probe of origin of the Hadron Mass. Quantitative evaluation of the chiral condensate in a nuclear medium

International Nuclear Information System (INIS)

Suzuki, Ken; Itahashi, Kenta; Hirenzaki, Satoru

2005-01-01

Spontaneous breaking of chiral symmetry is believed to be the mechanism which endows nucleus their large masses. The order parameter of the symmetry breaking is the chiral condensate, whose magnitude is predicted to decrease linearly as the nuclear density is increased. The reduction of quark condensate was quantitatively studied from recent precise measurement of deeply bound pionic 1s states on three tin (Sn) isotopes. We made use of the Gell-Mann-Oakes-Renner relation which connects the magnitude of quark-codensate to a pion decay constant, and then used the Tomozawa-Weinberg relation which relates the pion decay constant to an isovector strength of the pion-nucleus potential. The potential strength was determined by fitting the measured pionic 1s-state binding energies. The result shows that the quark-condensate strength is reduced by about 35% at normal nuclear density, compared with the ''vacuum'' value obtained from pionic hydrogen X-ray measurements. This is the first quantitative deduction of the quark condensate modification at finite nuclear density, and is an important step towards understanding the origin of hadron masses. (author)

Quadrupole interactions in pionic and muonic tantalum and rhenium

International Nuclear Information System (INIS)

Konijn, J.; Doesburg, W. van; Ewan, G.T; Johansson, T.; Tibell, G.

1981-01-01

The hyperfine splitting of pionic and muonic X-rays in natural Re has been studied using the known ratio (accurate to 1.6 parts in 10 5 ) of the quadrupole moments of the two naturally occurring 185 Re and 187 Re isotopes. From the hyperfine splitting of the 5g → 4f and 4f → 3d pionic X-rays the effective quadrupole hyperfine constants were determined to be 187 A 2 sup(e)sup(f)sup(f) (4f) = 1.163 +- 0.010 keV and 187 A 2 sup(e)sup(f)sup(f) (3d) = 5.39 +- 0.63 keV, giving strong interaction quadrupole shifts epsilon 2 (4f) = 46 +- 10 eV and epsilon 2 (3d) = 1.3 +- 0.6 keV. The strong interaction monopole shifts epsilon 0 and widths GAMMA 0 of the 5g, 4f and 3d levels have also been measured. For the two higher orbits, standard optical-potential calculations fit the measured shifts and widths quite well. The observed deeper-lying 3d state, however, has shifts and widths that differ by a factor of 2 or more from the predictions. From the measured quadrupole hyperfine constants of the 4f level we calculate the spectroscopic quadrupole moments to be 187 Qsup(μ) = 2.09 +- 0.04 b, 187 Qsup(π) = 2.07 +- 0.02 b, 185 Qsup(μ) = 2.21 +- 0.04 b, and 185 Qsup(π) = 2.18 +- 0.02 b. In addition, muonic X-rays from 181 Ta were observed; using the same methods for determining the quadrupole moments as above, a value of 181 Qsup(μ) = 3.28 +- 0.06 b was obtained, in good agreement with earlier published data. (orig.)

Pionic annihilation of antiprotons stopped on sup 3 He

Energy Technology Data Exchange (ETDEWEB)

Bendiscioli, G.; Filippini, V.; Rotondi, A.; Salvini, P.; Venaglioni, A. (Pavia Univ. (Italy). Dipt. di Fisica Nucleare e Teorica Istituto Nazionale di Fisica Nucleare, Pavia (Italy)); Bossolasco, S.; Bussa, M.P.; Busso, L.; Fava, L.; Ferrero, L.; Maggiora, A.; Panzieri, D.; Piragino, G.; Piragino, R.; Tosello, F. (Turin Univ. (Italy). Ist. di Fisica Generale Istituto Nazionale di Fisica Nucleare, Turin (Italy)); Batusov, Yu.A.; Falomkin, I.V.; Pontecorvo, G.B.; Rozhdestvensky, A.M.; Sapozhnikov, M.G.; Tretyak, V.I. (Joint Inst. for Nuclear Research, Dubna (USSR)); Guaraldo, C. (Istituto Nazionale di Fisica Nucleare, Frascati (Italy). Lab. Nazionale di Frascati); Lodi Rizzini, E. (Brescia Univ. (Italy). Dipt. di Automazione Industriale Istituto Nazionale di Fisica Nucleare, Turin (Italy)); Haatuft, A.; Halsteinslid, A.; Myklebost, K.; Olsen, J.M. (Bergen Univ. (Norway). Dept. of Physics); Breivik, F.O.; Jacobsen, T.; Soerensen, S.O. (Oslo Univ. (Norway). Physics Dept.); Balestra

1990-11-26

The pionic annihilation of antiprotons stopped on {sup 3}He nuclei in a self-shunted streamer chamber exposed to the antiproton beam of LEAR is studied. The data concern charged-particle multiplicity distributions, branching ratios for different final states, the probability of final-state interaction, {pi}{sup -}, {pi}{sup +}, p and d momentum spectra, like and unlike pion angular correlations, {pi} and other charged-particle angular correlations. The comparison of the {sup 3}He data with those obtained on {sup 1}H, {sup 2}H and {sup 4}He does not reveal relevant effects due to the increase of the nucleon number; the small differences can be seen as due to a weak final-state interaction. (orig.).

Light pionic atoms perspectives for precision experiments

International Nuclear Information System (INIS)

Gotta, D.

2005-01-01

During the last decades high-precision spectroscopy of exotic-atom x-rays profited in particular in the case of pions from the increasing number of stopped particles provided by the cyclotron trap at the accelerator facility of the Paul-Scherrer-Institut (PSI) together with modern detector concepts like charge-coupled devices (CCDs) and crystal spectrometers. Presently, priority is given to the study of the strong-interaction effects in the most elementary system - pionic hydrogen. However, the systems with two or more nucleons are as fundamental for the development of a theoretical description of hadronic matter. Furthermore, the de-excitation of exotic atoms involves a variety of atomic processes, which become accessible in detail due to the high resolution achievable with crystal spectrometers, e. g., parallel transitions, line splittings, broadenings and intensity distributions. In addition, first successful attempts for a microscopic description of the atomic cascade are available now, which should be subject to stringent tests both for atoms and molecules. (author)

Pionic atoms, the relativistic mean-field theory and the pion-nucleon scattering lenghts

International Nuclear Information System (INIS)

Goudsmit, P.F.A.; Leisi, H.J.; Matsinos, E.

1991-01-01

Analysing pionic-atom data of isoscalar nuclei within the relativistic mean-field (RMF) theory, we determine the pseudoscalar πNN mixing parameter x=0.24±0.06 (syst.) and the strength of the nuclear scalar meson field for pions, S π =-34±14 (syst.) MeV. We show that these values are compatible with the elementary π-N interaction. Our RMF model provides a solution to the long-standing problem of the s-wave repulsion. (orig.)

Description of the general properties of pionic atoms

International Nuclear Information System (INIS)

Cervantes S, B.R.

1979-01-01

The effects of the finite dimension of the nucleus and the strong interaction effects in the energy levels ls and 2p of pionic atoms are considered. The energy transition between these two levels are calculated using the method of perturbations of first order, considering a uniform distribution of nuclear charge, for the effect of the finite dimension of the nucleus and one local optical potential as a model for the strong interaction. The calculations were realized for 13 elements and the results were compared with the experimentally obtained, founding a relative difference around of 4%. In conclusion the author observed that the effects of the finite dimension and the strong interaction can be considered as first order perturbations in light atoms, and for heavy atoms this effects can be considered as of second order or higher perturbations. (author)

Calculation of the density shift and broadening of the transition lines in pionic helium: Computational problems

Energy Technology Data Exchange (ETDEWEB)

Bakalov, Dimitar, E-mail: dbakalov@inrne.bas.bg [Bulgarian Academy of Sciences, INRNE (Bulgaria)

2015-08-15

The potential energy surface and the computational codes, developed for the evaluation of the density shift and broadening of the spectral lines of laser-induced transitions from metastable states of antiprotonic helium, fail to produce convergent results in the case of pionic helium. We briefly analyze the encountered computational problems and outline possible solutions of the problems.

On the nucleon renormalization in many nucleon problems due to pionic degrees of freedom

International Nuclear Information System (INIS)

Sauer, P.U.; Sawicki, M.; Furui, Sadataka.

1985-01-01

Conceptual problems of unified two-nucleon force models are discussed. The force models are based on the pion-nucleon vertex and attempt a description of the nucleon-nucleon interaction below and above pion threshold. The conceptual problems arise from the nucleon renormalization due to pionic degrees of freedom. Keeping channels with a single pion only no renormalization procedure can be given which is consistent in the one-nucleon and in the many-nucleon systems. The medium dependence of the one-pion exchange potential is illustrated. (author)

Experimental determination of the relativistic fine-structure splitting in pionic Ti and Fe atoms

International Nuclear Information System (INIS)

Wang, K.; Boehm, F.; Bovet, E.; Hahn, A.A.; Henrikson, H.E.; Miller, J.P.; Powers, R.J.; Vogel, P.; Vuilleumier, J.; Kunselman, A.R.

1980-01-01

Using a high-resolution crystal spectrometer we have measured the relativistic angular-momentum splittings of the 5g-4f and 5f-4d transitions in pionic Ti and Fe atoms. The observed fine-structure splittings of 85.3 +- 3.0 eV in π - Ti and 158.5 +- 7.8 eV in π - Fe agree with the calculated splittings of 88.5 and 167.6 eV, respectively, arising from the Klein-Gordon equation and from small corrections due to vacuum polarization, strong interaction, and electron screening

Quantum electrodynamics tests and X-rays standards using pionic atoms and highly charged ions; Tests d'electrodynamique quantique et etalons de rayons-X a l'aide des atomes pioniques et des ions multicharges

Energy Technology Data Exchange (ETDEWEB)

Martino, Trassinelli

2005-12-15

The object of this thesis is to present a new measurement of the pion mass using pionic nitrogen X-ray spectroscopy and results on helium-like argon and sulphur spectroscopy. The new pion mass has been measured with an accuracy of 1.7 ppm, 30% better that the present world average value, and it is obtained from Bragg spectroscopy of 5 ->4 pionic nitrogen transitions using the theoretical predictions provided by quantum electrodynamics. We have got: m({pi}{sup -}) = (139.571042 {+-} 0.000210 {+-} 0.000110) where the first error is due to the statistics and the second is the systematic error. I present the calculation of the hyperfine structure and recoil corrections for pionic atoms using a new perturbation method for the Klein-Gordon equation. The spectrometer used for this measurement has been characterized with the relativistic M1 transitions from helium-like ions produced with a new device, the Electron-Cyclotron-Resonance Ion Trap. High statistics spectra from these ions have enabled us to measure transition energies with an accuracy of some ppm which has allowed us to compare theoretical predictions with experiment data. X-ray emission from pionic atoms and multicharged ions can be used to define new types of X-ray standards for energies of a few keV.

Three-body dynamics in one dimension: a test model for the three-nucleon system with irreducible pionic diagrams

International Nuclear Information System (INIS)

Melde, T.; Canton, L.; Svenne, J.P.

2002-01-01

We formulate the three-body problem in one dimension in terms of the (Faddeev-type) integral equation approach. As an application, we develop a spinless, one-dimensional (1-D) model that mimics three-nucleon dynamics in one dimension. Using simple two-body potentials that reproduce the deuteron binding, we obtain that the three-body system binds at about 7.5 MeV. We then consider two types of residual pionic corrections in the dynamical equation; one related to the 2π-exchange three-body diagram, the other to the 1π-exchange three-body diagram. We find that the first contribution can produce an additional binding effect of about 0.9 MeV. The second term produces smaller binding effects, which are, however, dependent on the uncertainty in the off-shell extrapolation of the two-body t-matrix. This presents interesting analogies with what occurs in three dimensions. The paper also discusses the general three-particle quantum scattering problem, for motion restricted to the fall line. (author)

A high resolution reflecting crystal spectrometer to measure 3 keV pionic hydrogen and deuterium X-rays

International Nuclear Information System (INIS)

Badertscher, A.; Bogdan, M.; Goudsmit, P.F.A.; Knecht, L.; Leisi, H.J.; Schroeder, H.C.; Sigg, D.; Zhao, Z.G.; Chatellard, D.; Egger, J.P.; Jeannet, E.; Aschenauer, E.C.; Gabathuler, K.; Simons, L.M.; Rusi El Hassani, A.J.

1993-01-01

A reflecting crystal spectrometer consisting of three cylindrically bent quartz (110) crystals is described. It was designed to measure the 3 keV K β X-rays from pionic hydrogen and deuterium. Charge coupled devices (CCDs) were used as X-ray detectors. Projecting the reflexes of all three crystals on one common focus, an instrumental energy resolution below 1 eV was obtained at an energy of 2.9 keV. (orig.)

Relativistic Chiral Mean Field Model for Finite Nuclei

Science.gov (United States)

Ogawa, Y.; Toki, H.; Tamenaga, S.; Haga, A.

2009-08-01

We present a relativistic chiral mean field (RCMF) model, which is a method for the proper treatment of pion-exchange interaction in the nuclear many-body problem. There the dominant term of the pionic correlation is expressed in two-particle two-hole (2p-2h) states with particle-holes having pionic quantum number, J^{π}. The charge-and-parity-projected relativistic mean field (CPPRMF) model developed so far treats surface properties of pionic correlation in 2p-2h states with J^{π} = 0^{-} (spherical ansatz). We extend the CPPRMF model by taking 2p-2h states with higher spin quantum numbers, J^{π} = 1^{+}, 2^{-}, 3^{+}, ... to describe the full strength of the pionic correlation in the intermediate range (r > 0.5 fm). We apply the RCMF model to the ^{4}He nucleus as a pilot calculation for the study of medium and heavy nuclei. We study the behavior of energy convergence with the pionic quantum number, J^{π}, and find convergence around J^{π}_{max} = 6^{-}. We include further the effect of the short-range repulsion in terms of the unitary correlation operator method (UCOM) for the central part of the pion-exchange interaction. The energy contribution of about 50% of the net two-body interaction comes from the tensor part and 20% comes from the spin-spin central part of the pion-exchange interaction.}

NΔ-NN interaction in the pionic disintegration of the deuteron

International Nuclear Information System (INIS)

Tanabe, H.; Ohta, K.

1987-07-01

The cross sections for the pionic disintegration of the deuteron in the Δ-resonance region are calculated based on a unitary three-body model. The NΔ-NN transition potential is constructed from the πN P 11 and P 33 scattering amplitudes extrapolated to the off-shell region, and from the πNN three-body propagator. The idea of the two-potential model for the P 11 wave is extended to the P 33 wave. The parameters of the model are deduced from the fits to the πN scattering phase shifts. It is found that the off-shell P 11 and P 33 scattering amplitudes behave quite similarly to the monopole form factor with a cut-off momentum Λ = 600 MeV/c as obtained earlier in the perturbation model by Gibbs, Gibson, and Stephenson. It is also found that the backward-propagating-pion component of the πNN propagator, which is often ignored in three-body calculations, is crucial to reproduce the magnitude of the total cross section. The three-body calculation is compared to the perturbation calculations. The second-order perturbation gives the results which closely approximate the full-order three-body calculation. (author)

High-resolution spectroscopy of deeply-bound pionic atoms in heavy nuclei by pion-transfer reactions of inverse kinematics using the GSI cooler ring ESR

International Nuclear Information System (INIS)

Yamazaki, Toshimitsu.

1991-02-01

Many studies published in the past are reviewed first in relation to high-resolution spectroscopy of deeply-bound pionic atoms in heavy nuclei. The report then describes a procedure for applying the method of inverse kinematics to the case of (d, 3 He) reactions. The (d, 3 He) reaction in inverse kinematics is feasible from practical viewpoints. Thus a discussion is made of the inverse kinematics in which a heavy-ion beam ( 208 Pb for instance) with a projectile kinetic energy hits a deuteron target and ejected recoil 3 He nuclei are measured in the forward direction. The recoil momentum is calculated as a function of the Q value. Analysis shows that the recoil spectroscopy with inverse kinematics can be applied to the case of (d, 3 He) reaction, which will yield a very high mass resolution. The experimental setup for use in the first stage is then outlined, and a simple detector configuration free of magnetic field is discussed. These investigations demonstrate that the (d, 3 He) reaction in inverse kinematics provides a promising tool for obtaining high-resolution spectra of deeply-bound pionic atoms. (N.K.)

Determination of the effective quadrupole moment in $^{181}$Ta with pionic x-rays

CERN Document Server

Beetz, R; Fransson, K; Konijn, J; Panman, J; Tauscher, Ludwig; Tibell, G

1978-01-01

From the hyperfine splitting of the 5g to 4f and the 6g to 4f pionic X-rays in /sup 181/Ta, an effective quadrupole moment of Q/sub eff /=3.58+or-0.03 b was determined. The strong interaction monopole shift epsilon /sub 0/ and the width Gamma /sub 0/ of the 4f level were measured to be epsilon /sub 0/=540+or-100 eV and Gamma /sub 0 /=225+or-57 eV, in good agreement with the values obtained with the standard optical potential description of the pion-nucleus interaction. Estimating the influence of the finite nuclear size, the deformation induced through the strong interaction between the pion and the finite nucleus, and the relative magnitude between the strong and the electromagnetic quadrupole coupling constants values for the spectroscopic quadrupole moment of Q=3.30+or-0.06 b, and for the intrinsic quadrupole moment of Q/sub 0/=7.06+or-0.12 b are obtained. (28 refs).

Long-range contributions to double beta decay revisited

Energy Technology Data Exchange (ETDEWEB)

Helo, J.C. [Universidad Técnica Federico Santa María, Centro-Científico-Tecnológico de Valparaíso,Casilla 110-V, Valparaíso (Chile); Departamento de Física, Facultad de Ciencias, Universidad de La Serena, Avenida Cisternas 1200, La Serena (Chile); Hirsch, M. [HEP Group, Instituto de Física Corpuscular,C.S.I.C./Universitat de València Edificio Institutos de Investigacion,Parc Cientific de Paterna, Apartado 22085, E-46071 València (Spain); Ota, T. [Department of Physics, Saitama University,Shimo-Okubo 255, 338-8570 Saitama-Sakura (Japan)

2016-06-01

We discuss the systematic decomposition of all dimension-7 (d=7) lepton number violating operators. These d=7 operators produce momentum enhanced contributions to the long-range part of the 0νββ decay amplitude and thus are severely constrained by existing half-live limits. In our list of possible models one can find contributions to the long-range amplitude discussed previously in the literature, such as the left-right symmetric model or scalar leptoquarks, as well as some new models not considered before. The d=7 operators generate Majorana neutrino mass terms either at tree-level, 1-loop or 2-loop level. We systematically compare constraints derived from the mass mechanism to those derived from the long-range 0νββ decay amplitude and classify our list of models accordingly. We also study one particular example decomposition, which produces neutrino masses at 2-loop level, can fit oscillation data and yields a large contribution to the long-range 0νββ decay amplitude, in some detail.

Double-Pionic Fusion of Nuclear Systems and the ''ABC'' Effect: Approaching a Puzzle by Exclusive and Kinematically Complete Measurements

International Nuclear Information System (INIS)

Bashkanov, M.; Clement, H.; Doroshkevich, E.; Khakimova, O.; Kren, F.; Meier, R.; Pricking, A.; Skorodko, T.; Wagner, G. J.; Bargholtz, C.; Geren, L.; Lindberg, K.; Tegner, P.-E.; Zartova, I.; Berlowski, M.; Stepaniak, J.; Bogoslawsky, D.; Ivanov, G.; Jiganov, E.; Morosov, B.

2009-01-01

The ABC effect--a puzzling low-mass enhancement in the ππ invariant mass spectrum, first observed by Abashian, Booth, and Crowe--is well known from inclusive measurements of two-pion production in nuclear fusion reactions. Here we report on the first exclusive and kinematically complete measurements of the most basic double-pionic fusion reaction pn→dπ 0 π 0 at beam energies of 1.03 and 1.35 GeV. The measurements, which have been carried out at CELSIUS-WASA, reveal the ABC effect to be a (ππ) I=L=0 channel phenomenon associated with both a resonancelike energy dependence in the integral cross section and the formation of a ΔΔ system in the intermediate state. A corresponding simple s-channel resonance ansatz provides a surprisingly good description of the data

High precision spectroscopy of pionic and antiprotonic atoms; Spectroscopie de precision des atomes pioniques et antiprotoniques

Energy Technology Data Exchange (ETDEWEB)

El-Khoury, P

1998-04-15

The study of exotic atoms, in which an orbiting electron of a normal atom is replaced by a negatively charged particle ({pi}{sup -}, {mu}{sup -}, p, {kappa}{sup -}, {sigma}{sup -},...) may provide information on the orbiting particle and the atomic nucleus, as well as on their interaction. In this work, we were interested in pionic atoms ({pi}{sup -14} N) on the one hand in order to determine the pion mass with high accuracy (4 ppm), and on the other hand in antiprotonic atoms (pp-bar) in order to study the strong nucleon-antinucleon interaction at threshold. In this respect, a high-resolution crystal spectrometer was coupled to a cyclotron trap which provides a high stop density for particles in gas targets at low pressure. Using curved crystals, an extended X-ray source could be imaged onto the detector. Charge-Coupled Devices were used as position sensitive detectors in order to measure the Bragg angle of the transition to a high precision. The use of gas targets resolved the ambiguity owing to the number of K electrons for the value of the pion mass, and, for the first time, strong interaction shift and broadening of the 2p level in antiprotonic hydrogen were measured directly. (author)

Double pionic fusion. Towards an understanding of the ABC puzzle by exclusive measurements

International Nuclear Information System (INIS)

Bashkanov, M.

2006-01-01

The ABC effect is a huge unexpected enhancement at twice the pion mass in the invariant mass spectrum of two pions, which are generated in double-pionic fusion to bound nuclear systems. This peculiar phenomenon has been missing a conclusive explanation all the time since it has been discovered 1960 in single-arm measurements of 3 He ejectiles in the reaction pd→ 3 HeX. One reason for this failure has been that all measurements to this subject have been inclusive, i.e., lacking the full experimentally accessible information. Hence exclusive measurements were performed at CELSIUS/WASA at an energy of T p =0.895 GeV, where the ABC effect is expected to be strongest. For the first time exclusive data of solid statistics for both the pd→ 3 Heπ 0 π 0 and pd→ 3 Heπ + π - reactions were obtained including also results for the three-pion production total cross-section. The new data are consistent with the previous inclusive data. They provide, however, much more additional information, which rule out all previous explications of the ABC effect. The now available kinematically complete set of data reveals that the low ππ-mass enhancement (ABC-effect): - is not necessarily associated with a high ππ-mass enhancement, - is always connected with the simultaneous excitation of two Δ resonances, - is of scalar-isoscalar nature, i.e. a σ-channel phenomenon, - requires dynamics in the reaction system, which has not been considered hitherto. Various possible solutions are discussed, however, all of them demand a high attraction in the ΔΔ system - a point, which has never been touched so far in theoretical and experimental investigations. For this data analysis new powerful methods based on neural nets have been developed. Their current and possible future applications are discussed. (orig.)

Exchange current contributions to quasi-elastic electron scattering

International Nuclear Information System (INIS)

Conte, J.S. Jr.

1981-01-01

Because electromagnetic interactions are weak and well understood, inelastic electron scattering has been very useful in elucidating aspects of nuclear structure. In the region of large electron energy loss, an extremely simple reaction picture (quasi-free knockout of a single nucleon or electroproduction of an isobar) and a simple nuclear model (Fermi gas) have provided both a good fit to experimental data and a dynamical determination of the nuclear Fermi momentum (k/sub F/). However, there exists an anomalous region where this picture fails. Two body correlations have not seemed to help give any better agreement. We have investigated the following questions: Do exchange current processes contribute importantly in this region. Do they help produce agreement with experiment. Also, how do they effect our previous picture of quasifree knockout. We calculate the effects of exchange currents in this region using the standard Feynman graph rules. We have included all important long range exchange currents: pair, pionic, and isobar exchange currents. We found it necessary to make non-relativistic reductions of these currents in order to facilitate calculations. The resulting multidimensional integrals were done using Monte Carlo techniques. All exchange currents which were investigated were found to be appreciable in the anomalous region, and also important in the quasi-free peak region. Inclusion of these amplitudes would supply all of the missing cross section in the anomalous region: however, it would destroy the agreement between theory and experiment in the region of the quasi-free nucleon peak, and thereby cast suspicion on the aforementioned dynamical determination of k/sub F/

Double pionic fusion. Towards an understanding of the ABC puzzle by exclusive measurements

Energy Technology Data Exchange (ETDEWEB)

Bashkanov, M.

2006-07-01

The ABC effect is a huge unexpected enhancement at twice the pion mass in the invariant mass spectrum of two pions, which are generated in double-pionic fusion to bound nuclear systems. This peculiar phenomenon has been missing a conclusive explanation all the time since it has been discovered 1960 in single-arm measurements of {sup 3}He ejectiles in the reaction pd{yields} {sup 3}HeX. One reason for this failure has been that all measurements to this subject have been inclusive, i.e., lacking the full experimentally accessible information. Hence exclusive measurements were performed at CELSIUS/WASA at an energy of T{sub p}=0.895 GeV, where the ABC effect is expected to be strongest. For the first time exclusive data of solid statistics for both the pd{yields}{sup 3}He{pi}{sup 0}{pi}{sup 0} and pd{yields}{sup 3}He{pi}{sup +}{pi}{sup -} reactions were obtained including also results for the three-pion production total cross-section. The new data are consistent with the previous inclusive data. They provide, however, much more additional information, which rule out all previous explications of the ABC effect. The now available kinematically complete set of data reveals that the low {pi}{pi}-mass enhancement (ABC-effect): - is not necessarily associated with a high {pi}{pi}-mass enhancement, - is always connected with the simultaneous excitation of two {delta} resonances, - is of scalar-isoscalar nature, i.e. a {sigma}-channel phenomenon, - requires dynamics in the reaction system, which has not been considered hitherto. Various possible solutions are discussed, however, all of them demand a high attraction in the {delta}{delta} system - a point, which has never been touched so far in theoretical and experimental investigations. For this data analysis new powerful methods based on neural nets have been developed. Their current and possible future applications are discussed. (orig.)

Chiral model predictions for electromagnetic polarizabilities of the nucleon: A 'consumer report'

International Nuclear Information System (INIS)

Broniowski, W.

1992-01-01

This contribution has two parts: (1) The author critically discusses predictions for the electromagnetic polarizabilities of the nucleon obtained in two different approaches: (a) hedgehog models (HM), such as Skyrmions, chiral quark models, hybrid bags, NJL etc., and (b) chiral perturbation theory (χPT). (2) The author shows new results obtained in HM: N c -counting of polarizabilities, splitting of the neutron and proton polarizabilities (he argues that α n > α p in models with pionic clouds), relevance of dispersive terms in the magnetic polarizability β, important role of the Δ resonance in pionic loops, and the effects of non-minimal substitution terms in the effective lagrangian. 3 refs

Real-pion states formed by virtual-pion beam

International Nuclear Information System (INIS)

Yamazaki, Toshimitsu.

1990-04-01

Deeply bound pionic states are discussed from various points of view; highly excited nuclear states as a cluster family of pionic bound states, Σ atom/Σ hypernuclei, halo-like density distributions, virtual pion beam to produce pionic states, etc. (author)

Mesonic atoms. Technical progress report

International Nuclear Information System (INIS)

Kunselman, R.

1981-01-01

Research on mesic atoms during 1981 is reported. This includes measurement of x-rays from pionic hydrogen and pionic deuterium; muonic K, L, and M x-ray spectra of mercury 199 and mercury 201; and pionic chromium 54, scandium 45, vanadium 51, manganese 55, and iron

Species contributions to single biodiversity values under-estimate whole community contribution to a wider range of values to society.

Science.gov (United States)

Hiron, Matthew; Pärt, Tomas; Siriwardena, Gavin M; Whittingham, Mark J

2018-05-03

A major task for decision makers is deciding how to consider monetary, cultural and conservation values of biodiversity explicitly when planning sustainable land use. Thus, there is a great need to understand just what "valuing" biodiversity or species really means, e.g. regarding how many and which species are important in providing ecosystem services or other values. Constructing ecosystem-level indices, however, requires weighting the relative contribution of species to the different values. Using farmland birds, we illustrate how species contribute to different biodiversity values, namely utilitarian (pest seed predation potential), cultural (species occurrence in poetry), conservational (declines and rarity) and inherent (all species equal) value. Major contributions to each value are often made by a subset of the community and different species are important for different values, leading to no correlations or, in some cases, negative correlations between species' relative contributions to different values. Our results and methods using relative contributions of species to biodiversity values can aid decisions when weighing different values in policies and strategies for natural resource management. We conclude that acknowledging the importance of the range of biodiversity values that are apparent from different perspectives is critical if the full value of biodiversity to society is to be realised.

Nuclei with exotic constituents

International Nuclear Information System (INIS)

Yamazaki, Toshimitsu.

1990-08-01

We discuss various interesting features in the behavior of exotic constituents of nuclei such as hyperons and mesons, in particular, with emphases on the aspect of exotic halos which are formed in general by short-range repulsion and long-range attraction. Specifically, Λ and Σ hypernuclei and pionic nuclei are discussed. (author)

Pionic decays of phi (1020) and f' (1514)

International Nuclear Information System (INIS)

Pasupathy, J.; Singh, C.A.

1978-01-01

The decay amplitudes phi (1020) → 3π and f' (1514) → ππ are calculated using unitarity corrections to the Okubo-Zweig-Iizuka rule. We use dispersion relations for the amplitudes phi → rhoπ and f' → ππ and evaluate the contributions arising from intermediate states such as KK-bar, K*K-bar, etc. The KK-bar intermediate state contributes to the absorptive part of the amplitude phi → rhoπ a value which corresponds to a partial width GAMMA (phi → 3π) of 150 keV. The contribution of the KK-bar and K*K-bar + K-barK* to the dispersive part of the amplitude phi → rhoπ within the context of approximations employed by us is somewhat larger and corresponds to a partial width of 900 keV for phi → 3π. For the f' → ππ amplitude we have evaluated the contributions of the KK-bar, etaeta, and K*K-bar + K-bar*K intermediate states using the dual model for the amplitudes KK-bar → ππ, etaeta → ππ, and K*K-bar → ππ. The effective strength of the amplitude f' → ππ arising from such unitarity corrections to the Okubo-Zweig-Iizuka rule corresponds to a partial width GAMMA (f' → ππ) of 170 keV via the absorptive part and a value of 500 keV via the dispersive part

Isospin breaking in pion-nucleon scattering at threshold by radiative processes

CERN Document Server

Ericson, Torleif Eric Oskar

2006-01-01

We investigate the dispersive contribution by radiative processes such as (pi- proton to neutron gamma) and (pi- proton to Delta gamma) to the pion-nucleon scattering lengths of charged pions in the heavy baryon limit. They give a large isospin violating contribution in the corresponding isoscalar scattering length, but only a small violation in the isovector one. These terms contribute 6.3(3)% to the 1s level shift of pionic hydrogen and give a chiral constant F_pi^2f_1=-25.8(8) MeV.

Fermi liquid description of relativistic high density matter

Science.gov (United States)

Pal, K.; Dutt-Mazumder, A. K.

2011-06-01

We calculate pionic contribution to the relativistic Fermi Liquid parameters (RFLPs) using Chiral Effective Lagrangian. The RFLPs so determined are then used to calculate chemical potential, exchange energy due to πN interaction. We also compare the results of exchange energy from two loop ring diagrams involving σ, ω and π meson with what one obtains from the relativistic Fermi Liquid theory (RFLT).

Design, instrumentation and response characteristics of a 2 pi multi-detector of CsI(Tl) scintillators mounted inside the Plastic Ball spectrometer

NARCIS (Netherlands)

Joulaeizadeh, L.; Gasparic, I.; Bacelar, J.; Caplar, R.; Löhner, H.

2010-01-01

A 2 pi hemispherical detector consisting of 64 CsI(Tl) scintillator modules covering the angular range of 80 degrees -160 degrees has been constructed. This detector is employed as the Inner Shell of the Plastic Ball detector and was used in two experimental programs concerning the study of pionic

Decay of bubble of disoriented chiral condensate

International Nuclear Information System (INIS)

Gani, V.A.; Kudryavtsev, A.E.; Belova, T.I.

1999-01-01

The space-time structure for the process of decay of a bubble of hypothetical phase -disoriented chiral condensate (DCC) i discussed. The evolution of the initial classical field configuration corresponding to the bubble of DCC is studied, both numerically and analytically. The decay of this initial configuration depends crucially on self-interaction of the pionic fields. It is shown that in some cases this self-interaction leads to the formation of sort of breather solution, formed from pionic fields situated in the center of the initial bubble of DCC. This breather looks like a long-lived source of pionic fields [ru

SU-E-J-125: Classification of CBCT Noises in Terms of Their Contribution to Proton Range Uncertainty

International Nuclear Information System (INIS)

Brousmiche, S; Orban de Xivry, J; Macq, B; Seco, J

2014-01-01

Purpose: This study assesses the potential use of CBCT images in adaptive protontherapy by estimating the contribution of the main sources of noise and calibration errors to the proton range uncertainty. Methods: Measurements intended to highlight each particular source have been achieved by adapting either the testbench configuration, e.g. use of filtration, fan-beam collimation, beam stop arrays, phantoms and detector reset light, or the sequence of correction algorithms including water precorrection. Additional Monte-Carlo simulations have been performed to complement these measurements, especially for the beam hardening and the scatter cases. Simulations of proton beams penetration through the resulting images have then been carried out to quantify the range change due to these effects. The particular case of a brain irradiation is considered mainly because of the multiple effects that the skull bones have on the internal soft tissues. Results: On top of the range error sources is the undercorrection of scatter. Its influence has been analyzed from a comparison of fan-beam and full axial FOV acquisitions. In this case, large range errors of about 12 mm can be reached if the assumption is made that the scatter has only a constant contribution over the projection images. Even the detector lag, which a priori induces a much smaller effect, has been shown to contribute for up to 2 mm to the overall error if its correction only aims at reducing the skin artefact. This last result can partially be understood by the larger interface between tissues and bones inside the skull. Conclusion: This study has set the basis of a more systematical analysis of the effect CBCT noise on range uncertainties based on a combination of measurements, simulations and theoretical results. With our method, even more subtle effects such as the cone-beam artifact or the detector lag can be assessed. SBR and JOR are financed by iMagX, a public-private partnership between the region Wallone

Analysis of long- and short-range contribution to adhesion work in cardiac fibroblasts: An atomic force microscopy study

Energy Technology Data Exchange (ETDEWEB)

Sbaizero, O., E-mail: sbaizero@units.it [Department of Engineering and Architecture, University of Trieste (Italy); University of Colorado Cardiovascular Institute, University of Colorado Denver, Aurora (United States); DelFavero, G. [Department of Engineering and Architecture, University of Trieste (Italy); Martinelli, V. [International Center for Genetic Engineering and Biotechnology, Trieste (Italy); Long, C.S.; Mestroni, L. [University of Colorado Cardiovascular Institute, University of Colorado Denver, Aurora (United States)

2015-04-01

Atomic force microscopy (AFM) for single-cell force spectroscopy (SCFS) and Poisson statistic were used to analyze the detachment work recorded during the removal of gold-covered microspheres from cardiac fibroblasts. The effect of Cytochalasin D, a disruptor of the actin cytoskeleton, on cell adhesion was also tested. The adhesion work was assessed using a Poisson analysis also derived from single-cell force spectroscopy retracting curves. The use of Poisson analysis to get adhesion work from AFM curves is quite a novel method, and in this case, proved to be effective to study the short-range and long-range contributions to the adhesion work. This method avoids the difficult identification of minor peaks in the AFM retracting curves by creating what can be considered an average adhesion work. Even though the effect of actin depolymerisation is well documented, its use revealed that control cardiac fibroblasts (CT) exhibit a work of adhesion at least 5 times higher than that of the Cytochalasin treated cells. However, our results indicate that in both cells short-range and long-range contributions to the adhesion work are nearly equal and the same heterogeneity index describes both cells. Therefore, we infer that the different adhesion behaviors might be explained by the presence of fewer membrane adhesion molecules available at the AFM tip–cell interface under circumstances where the actin cytoskeleton has been disrupted. - Highlights: • AFM force–deformation curve was used to characterize the cardiac fibroblast adhesion behavior. • The amount and nature of adhesion were assessed using a Poisson analysis applied to the AFM curve. • The work of adhesion for control cells was about four times higher than that of the Cyt-D treated cells. • Short- and long-range contributions to adhesion are nearly equal for both control and treated cells.

Two-nucleon electromagnetic current in chiral effective field theory: One-pion exchange and short-range contributions

International Nuclear Information System (INIS)

Koelling, S.; Epelbaum, E.; Krebs, H.; Meissner, U.-G.

2011-01-01

We derive the leading one-loop contribution to the one-pion exchange and short-range two-nucleon electromagnetic current operator in the framework of chiral effective field theory. The derivation is carried out using the method of unitary transformation. Explicit results for the current and charge densities are given in momentum and coordinate space.

Signature of Plausible Accreting Supermassive Black Holes in Mrk 261/262 and Mrk 266

Directory of Open Access Journals (Sweden)

Gagik Ter-Kazarian

2013-01-01

Full Text Available We address the neutrino radiation of plausible accreting supermassive black holes closely linking to the 5 nuclear components of galaxy samples of Mrk 261/262 and Mrk 266. We predict a time delay before neutrino emission of the same scale as the age of the Universe. The ultrahigh energy neutrinos are produced in superdense protomatter medium via simple (quark or pionic reactions or modified URCA processes (G. Gamow was inspired to name the process URCA after the name of a casino in Rio de Janeiro. The resulting neutrino fluxes for quark reactions are ranging from to , where is the opening parameter. For pionic and modified URCA reactions, the fluxes are and , respectively. These fluxes are highly beamed along the plane of accretion disk, peaked at ultrahigh energies, and collimated in smaller opening angle .

Fermi liquid description of relativistic high density matter

International Nuclear Information System (INIS)

Pal, K.; Dutt-Mazumder, A.K.

2011-01-01

We calculate pionic contribution to the relativistic Fermi Liquid parameters (RFLPs) using Chiral Effective Lagrangian. The RFLPs so determined are then used to calculate chemical potential, exchange energy due to πN interaction. We also compare the results of exchange energy from two loop ring diagrams involving σ, ω and π meson with what one obtains from the relativistic Fermi Liquid theory (RFLT). (author)

Isotopic spin effect in three-pion Bose-Einstein correlations

International Nuclear Information System (INIS)

Suzuki, N.

1998-01-01

Bose-Einstein (BE) correlations of identical particles in multiple production processes are extensively studied last years because they give an information on the space-time region of interaction. The basic effect is analogous to Hanbury-Brown - Twiss (HBT) interferometry in optics and suggests statistical production of the particles (mainly π mesons). The possible presence of coherent pionic component (for example, in the case of disoriented chiral condensate formation) modifies the HBT effect. On the other hand, the pions (contrary to photons) are subject to isotopic spin (and electric charge) conservation and so they can not be emitted independently. While the corresponding change of the statistical part is not essential for large multiplicities, the coherent part changes substantially when isotopic spin conservation is taken into account. BE correlations of the pions in the presence of both statistical and coherent components are reconsidered taking into account isotopic spin conservation in the coherent part. That will result in appearance of additional contribution to pionic correlation function. (author)

Capture and transfer of pions in hydrogenous materials

International Nuclear Information System (INIS)

Armstrong, D.S.

1990-05-01

Pionic hydrogen is a short-lived exotic hydrogen isotope in which a negative pion replaces the atomic electron. The formation and subsequent interactions of pionic hydrogen are discussed, with emphasis on the process of pion transfer. Recent results using the pion charge-exchange reaction (π - , π 0 ) obtained at TRIUMF are reviewed. (Author) (35 refs., 3 tabs., 9 figs.)

Contribution of silicon recombination properties in resolution of short-range particle detectors

International Nuclear Information System (INIS)

Verbitskaya, E.M.; Eremin, V.K.; Malyarenko, A.M.; Strokan, N.B.; Sukhanov, V.L.

1987-01-01

Tracks of short-range particles represent dense clusters of electron-hole pairs 2-4 μm in diameter and 20-30 μm long. Thus, conditions for charge carrier transport in microscopic Si volume are discovered at registration of each particle. Statistical distribution by the specimen square of the main parameter - lifetime of charge carriers (τ) is disclosed as a result of particle chaotic hitting the detector. Analytical description for the shape of the spectral line of the detector is found in the assumption of Gauss distribution τ. The function is applied to the analysis of detector spectra with maximum energy resolution, for which contributions to the shape of the line of the fundamental factors and nonperfection of Si or of the detector structure as a whole are comparable. Excess fluctuations of α-particle energy transformation to the charge of electron-hole pairs are found relatively to adopted values

Contribution of silicon recombination properties in resolution of short-range particle detectors

Energy Technology Data Exchange (ETDEWEB)

Verbitskaya, E M; Eremin, V K; Malyarenko, A M; Strokan, N B; Sukhanov, V L

1987-10-01

Tracks of short-range particles represent dense clusters of electron-hole pairs 2-4 ..mu..m in diameter and 20-30 ..mu..m long. Thus, conditions for charge carrier transport in microscopic Si volume are discovered at registration of each particle. Statistical distribution by the specimen square of the main parameter - lifetime of charge carriers (tau) is disclosed as a result of particle chaotic hitting the detector. Analytical description for the shape of the spectral line of the detector is found in the assumption of Gauss distribution tau. The function is applied to the analysis of detector spectra with maximum energy resolution, for which contributions to the shape of the line of the fundamental factors and nonperfection of Si or of the detector structure as a whole are comparable. Excess fluctuations of ..cap alpha..-particle energy transformation to the charge of electron-hole pairs are found relatively to adopted values.

The ABC effect in double-pionic fusion to deuterium

International Nuclear Information System (INIS)

Khakimova, Olena

2009-01-01

In this work the first exclusive measurements of the reaction pd→pdπ 0 π 0 have been carried out at beam energies of T p =1.03 and 1.35 GeV at CELSIUS storage ring in Uppsala/Sweden. The reaction pn→dπ 0 π 0 has been measured as quasifree pd→ p spec dπ 0 π 0 reaction with a spectator proton p spec of very small momentum. Since all particles except of the spectator proton have been measured, the spectator 4-momentum could be reconstructed by kinematical fits with 3 overconstraints. Hence one could exploit the Fermi motion of the target neutron to cover a range of relative energies in the pn-system for a given beam energy. The π 0 π 0 channel, which is purely isoscalar and free of any isovector contributions, shows a large low-mass enhancement in the M π 0 π 0 spectrum, which is much larger than observed in the inclusive measurements and also larger than predicted in previous ΔΔ calculations. In contrast to these and also to the inclusive data a high-mass enhancement in the M π 0 π 0 spectrum was not observed and is meanwhile interpreted as 3π and η-meson production. All exclusive data can be described, if one assumes a resonance in the isoscalar pn-system, which dominantly decays via the isoscalar ΔΔ system. With this so-called s-channel resonance ansatz a very good description of the data in the total cross section as well as in the differential spectra has been achieved. Mass and width of this isoscalar dibaryonic resonance are M R ∼2.36 GeV/c 2 and Γ R ∼80 MeV, respectively. (orig.)

Reduction of the chiral order parameter by a nuclear medium

International Nuclear Information System (INIS)

Kienle, P.; Yamazaki, Toshimizu

2001-01-01

We propose a model independent procedure to deduce from the 1s-binding energy of heavy, neutron rich pionic atoms, the isovector scattering length b 1 of the pion nucleus interaction. It is related to the pion decay constant f π , the order parameter of spontaneous chiral symmetry breaking and thus to the value of the chiral quark condensate. Based on the results with pionic 205 Pb, we find with the assertion that only the isovector part of the pion-nucleus interaction be modified by a QCD effect, a reduction of the quark condensate by 30% in a 205 Pb nucleus. Forthcoming experiments to measure pionic 1s-binding energies in Sn-isotopes, including isotope shifts, will yield decisive information on the quark condensate without assertion. (orig.)

Decay of hypernuclei

International Nuclear Information System (INIS)

Bando, H.

1985-01-01

The pionic and non-mesonic decays of hypernuclei are discussed. In the first part, various decay processes which could be useful to obtain information of hypernuclear structure are discussed. The experimental data concerning the pionic and non-mesonic decays are discussed in the second part. As the experimental data, there are only few lifetime data and some crude data on the non-mesonic to π decay ratio. In the third and the fourth parts, some theoretical analyses are made on the pionic and the nonmesonic decays. DDHF calculation was performed for Λ and N systems by using Skyrme type ΛN and NN effective interactions. A suppression factor of the order of 10 -3 for A nearly equal 100 was obtained. (Aoki, K.)

How Confinement-Induced Structures Alter the Contribution of Hydrodynamic and Short-Ranged Repulsion Forces to the Viscosity of Colloidal Suspensions

Directory of Open Access Journals (Sweden)

Meera Ramaswamy

2017-10-01

Full Text Available Confined systems ranging from the atomic to the granular are ubiquitous in nature. Experiments and simulations of such atomic and granular systems have shown a complex relationship between the microstructural arrangements under confinement, the short-ranged particle stresses, and flow fields. Understanding the same correlation between structure and rheology in the colloidal regime is important due to the significance of such suspensions in industrial applications. Moreover, colloidal suspensions exhibit a wide range of structures under confinement that could considerably modify such force balances and the resulting viscosity. Here, we use a combination of experiments and simulations to elucidate how confinement-induced structures alter the relative contributions of hydrodynamic and short-range repulsive forces to produce up to a tenfold change in the viscosity. In the experiments we use a custom-built confocal rheoscope to image the particle configurations of a colloidal suspension while simultaneously measuring its stress response. We find that as the gap decreases below 15 particle diameters, the viscosity first decreases from its bulk value, shows fluctuations with the gap, and then sharply increases for gaps below 3 particle diameters. These trends in the viscosity are shown to strongly correlate with the suspension microstructure. Further, we compare our experimental results to those from two different simulations techniques, which enables us to determine the relative contributions of hydrodynamic and short-range repulsive stresses to the suspension rheology. The first method uses the lubrication approximation to find the hydrodynamic stress and includes a short-range repulsive force between the particles while the second is a Stokesian dynamics simulation that calculates the full hydrodynamic stress in the suspension. We find that the decrease in the viscosity at moderate confinements has a significant contribution from both the

A contribution to laser range imaging technology

Science.gov (United States)

Defigueiredo, Rui J. P.; Denney, Bradley S.

1991-01-01

The goal of the project was to develop a methodology for fusion of a Laser Range Imaging Device (LRID) and camera data. Our initial work in the project led to the conclusion that none of the LRID's that were available were sufficiently adequate for this purpose. Thus we spent the time and effort on the development of the new LRID with several novel features which elicit the desired fusion objectives. In what follows, we describe the device developed and built under contract. The Laser Range Imaging Device (LRID) is an instrument which scans a scene using a laser and returns range and reflection intensity data. Such a system would be extremely useful in scene analysis in industry and space applications. The LRID will be eventually implemented on board a mobile robot. The current system has several advantages over some commercially available systems. One improvement is the use of X-Y galvonometer scanning mirrors instead of polygonal mirrors present in some systems. The advantage of the X-Y scanning mirrors is that the mirror system can be programmed to provide adjustable scanning regions. For each mirror there are two controls accessible by the computer. The first is the mirror position and the second is a zoom factor which modifies the amplitude of the position of the parameter. Another advantage of the LRID is the use of a visible low power laser. Some of the commercial systems use a higher intensity invisible laser which causes safety concerns. By using a low power visible laser, not only can one see the beam and avoid direct eye contact, but also the lower intensity reduces the risk of damage to the eye, and no protective eyeware is required.

Santa Rita Experimental Range: 100 years (1903 to 2003) of accomplishments and contributions; conference proceedings; 2003 October 30-November 1; Tucson, AZ

Science.gov (United States)

Mitchel P. McClaran; Peter F. Ffolliott; Carleton B. Edminster

2003-01-01

The purpose of this conference was to celebrate the 100 years of accomplishments and contributions of the Santa Rita Experimental Range, the longest continuously operating research area dedicated to the sustainable management of North American rangelands. The conference consisted of one-and-a-half days of invited synthesis papers and contributed poster presentations...

Precision calculation of threshold πd scattering, πN scattering lengths, and the GMO sum rule

Science.gov (United States)

Baru, V.; Hanhart, C.; Hoferichter, M.; Kubis, B.; Nogga, A.; Phillips, D. R.

2011-12-01

We use chiral perturbation theory (ChPT) to calculate the πd scattering length with an accuracy of a few percent, including isospin-violating corrections in both the two- and three-body sectors. In particular, we provide the technical details of a recent letter (Baru et al., 2011) [1], where we used data on pionic deuterium and pionic hydrogen atoms to extract the isoscalar and isovector pion-nucleon scattering lengths a and a. We study isospin-breaking contributions to the three-body part of a due to mass differences, isospin violation in the πN scattering lengths, and virtual photons. This last class of effects is ostensibly infrared enhanced due to the smallness of the deuteron binding energy. However, we show that the leading virtual-photon effects that might undergo such enhancement cancel, and hence the standard ChPT counting provides a reliable estimate of isospin violation in a due to virtual photons. Finally, we discuss the validity of the Goldberger-Miyazawa-Oehme sum rule in the presence of isospin violation, and use it to determine the charged-pion-nucleon coupling constant.

The ABC effect in double-pionic fusion to deuterium

Energy Technology Data Exchange (ETDEWEB)

Khakimova, Olena

2009-04-17

In this work the first exclusive measurements of the reaction pd{yields}pd{pi}{sup 0}{pi}{sup 0} have been carried out at beam energies of T{sub p}=1.03 and 1.35 GeV at CELSIUS storage ring in Uppsala/Sweden. The reaction pn{yields}d{pi}{sup 0}{pi}{sup 0} has been measured as quasifree pd{yields} p{sub spec}d{pi}{sup 0}{pi}{sup 0} reaction with a spectator proton p{sub spec} of very small momentum. Since all particles except of the spectator proton have been measured, the spectator 4-momentum could be reconstructed by kinematical fits with 3 overconstraints. Hence one could exploit the Fermi motion of the target neutron to cover a range of relative energies in the pn-system for a given beam energy. The {pi}{sup 0}{pi}{sup 0} channel, which is purely isoscalar and free of any isovector contributions, shows a large low-mass enhancement in the M{sub {pi}{sup 0}}{sub {pi}{sup 0}} spectrum, which is much larger than observed in the inclusive measurements and also larger than predicted in previous {delta}{delta} calculations. In contrast to these and also to the inclusive data a high-mass enhancement in the M{sub {pi}{sup 0}}{sub {pi}{sup 0}} spectrum was not observed and is meanwhile interpreted as 3{pi} and {eta}-meson production. All exclusive data can be described, if one assumes a resonance in the isoscalar pn-system, which dominantly decays via the isoscalar {delta}{delta} system. With this so-called s-channel resonance ansatz a very good description of the data in the total cross section as well as in the differential spectra has been achieved. Mass and width of this isoscalar dibaryonic resonance are M{sub R}{approx}2.36 GeV/c{sup 2} and {gamma}{sub R}{approx}80 MeV, respectively. (orig.)

Contributions of gut bacteria to Bacillus thuringiensis-induced mortality vary across a range of Lepidoptera

Directory of Open Access Journals (Sweden)

Holt Jonathan

2009-03-01

Full Text Available Abstract Background Gut microbiota contribute to the health of their hosts, and alterations in the composition of this microbiota can lead to disease. Previously, we demonstrated that indigenous gut bacteria were required for the insecticidal toxin of Bacillus thuringiensis to kill the gypsy moth, Lymantria dispar. B. thuringiensis and its associated insecticidal toxins are commonly used for the control of lepidopteran pests. A variety of factors associated with the insect host, B. thuringiensis strain, and environment affect the wide range of susceptibilities among Lepidoptera, but the interaction of gut bacteria with these factors is not understood. To assess the contribution of gut bacteria to B. thuringiensis susceptibility across a range of Lepidoptera we examined larval mortality of six species in the presence and absence of their indigenous gut bacteria. We then assessed the effect of feeding an enteric bacterium isolated from L. dispar on larval mortality following ingestion of B. thuringiensis toxin. Results Oral administration of antibiotics reduced larval mortality due to B. thuringiensis in five of six species tested. These included Vanessa cardui (L., Manduca sexta (L., Pieris rapae (L. and Heliothis virescens (F. treated with a formulation composed of B. thuringiensis cells and toxins (DiPel, and Lymantria dispar (L. treated with a cell-free formulation of B. thuringiensis toxin (MVPII. Antibiotics eliminated populations of gut bacteria below detectable levels in each of the insects, with the exception of H. virescens, which did not have detectable gut bacteria prior to treatment. Oral administration of the Gram-negative Enterobacter sp. NAB3, an indigenous gut resident of L. dispar, restored larval mortality in all four of the species in which antibiotics both reduced susceptibility to B. thuringiensis and eliminated gut bacteria, but not in H. virescens. In contrast, ingestion of B. thuringiensis toxin (MVPII following antibiotic

Formation of fast exotic atoms by radiative Coulomb capture

International Nuclear Information System (INIS)

Chatterjee, L.; Das, G.; Chakravorty, A.; Goswami, R.; Mondal, S.K.

1993-01-01

Interesting surprises in some exotic atom kinetics have been reported recently. These involve muonic atom transfer cross sections, nuclear pion capture and the q 1s effect in μCF. These can be explained if the exotic atom population contains a contributing fast component. Such fast atoms can be formed by radiative continuum to bound transitions of fast (keV) muons or pions. Cross sections for formation of such fast pionic and muonic atoms and their velocity distributions are reported. The possibility of these processes competing with the thermalisation channels and contributing effectively to the exotic atom population discussed. (orig.)

On the contribution of local feedback mechanisms to the range of climate sensitivity in two GCM ensembles

Energy Technology Data Exchange (ETDEWEB)

Webb, M.J.; Senior, C.A.; Sexton, D.M.H.; Ingram, W.J.; Williams, K.D.; Ringer, M.A. [Hadley Centre for Climate Prediction and Research, Met Office, Exeter (United Kingdom); McAvaney, B.J.; Colman, R. [Bureau of Meteorology Research Centre (BMRC), Melbourne (Australia); Soden, B.J. [University of Miami, Rosenstiel School for Marine and Atmospheric Science, Miami, FL (United States); Gudgel, R.; Knutson, T. [Geophysical Fluid Dynamics Laboratory (GFDL), Princeton, NJ (United States); Emori, S.; Ogura, T. [National Institute for Environmental Studies (NIES), Tsukuba (Japan); Tsushima, Y. [Japan Agency for Marine-Earth Science and Technology, Frontier Research Center for Global Change (FRCGC), Kanagawa (Japan); Andronova, N. [University of Michigan, Department of Atmospheric, Oceanic and Space Sciences, Ann Arbor, MI (United States); Li, B. [University of Illinois at Urbana-Champaign (UIUC), Department of Atmospheric Sciences, Urbana, IL (United States); Musat, I.; Bony, S. [Institut Pierre Simon Laplace (IPSL), Paris (France); Taylor, K.E. [Program for Climate Model Diagnosis and Intercomparison (PCMDI), Livermore, CA (United States)

2006-07-15

Global and local feedback analysis techniques have been applied to two ensembles of mixed layer equilibrium CO{sub 2} doubling climate change experiments, from the CFMIP (Cloud Feedback Model Intercomparison Project) and QUMP (Quantifying Uncertainty in Model Predictions) projects. Neither of these new ensembles shows evidence of a statistically significant change in the ensemble mean or variance in global mean climate sensitivity when compared with the results from the mixed layer models quoted in the Third Assessment Report of the IPCC. Global mean feedback analysis of these two ensembles confirms the large contribution made by inter-model differences in cloud feedbacks to those in climate sensitivity in earlier studies; net cloud feedbacks are responsible for 66% of the inter-model variance in the total feedback in the CFMIP ensemble and 85% in the QUMP ensemble. The ensemble mean global feedback components are all statistically indistinguishable between the two ensembles, except for the clear-sky shortwave feedback which is stronger in the CFMIP ensemble. While ensemble variances of the shortwave cloud feedback and both clear-sky feedback terms are larger in CFMIP, there is considerable overlap in the cloud feedback ranges; QUMP spans 80% or more of the CFMIP ranges in longwave and shortwave cloud feedback. We introduce a local cloud feedback classification system which distinguishes different types of cloud feedbacks on the basis of the relative strengths of their longwave and shortwave components, and interpret these in terms of responses of different cloud types diagnosed by the International Satellite Cloud Climatology Project simulator. In the CFMIP ensemble, areas where low-top cloud changes constitute the largest cloud response are responsible for 59% of the contribution from cloud feedback to the variance in the total feedback. A similar figure is found for the QUMP ensemble. Areas of positive low cloud feedback (associated with reductions in low level

Are changing emission patterns across the Northern Hemisphere influencing long-range transport contributions to background air pollution?

Science.gov (United States)

Mathur, R.; Kang, D.; Napelenok, S. L.; Xing, J.; Hogrefe, C.

2017-12-01

Air pollution reduction strategies for a region are complicated not only by the interplay of local emissions sources and several complex physical, chemical, dynamical processes in the atmosphere, but also hemispheric background levels of pollutants. Contrasting changes in emission patterns across the globe (e.g. declining emissions in North America and Western Europe in response to implementation of control measures and increasing emissions across Asia due to economic and population growth) are resulting in heterogeneous changes in the tropospheric chemical composition and are likely altering long-range transport impacts and consequently background pollution levels at receptor regions. To quantify these impacts, the WRF-CMAQ model is expanded to hemispheric scales and multi-decadal model simulations are performed for the period spanning 1990-2010 to examine changes in hemispheric air pollution resulting from changes in emissions over this period. Simulated trends in ozone and precursor species concentrations across the U.S. and the Northern Hemisphere over the past two decades are compared with those inferred from available measurements during this period. Additionally, the decoupled direct method (DDM) in CMAQ, a first- and higher-order sensitivity calculation technique, is used to estimate the sensitivity of O3 to emissions from different source regions across the Northern Hemisphere. The seasonal variations in source region contributions to background O3 are then estimated from these sensitivity calculations and will be discussed. These source region sensitivities estimated from DDM are then combined with the multi-decadal simulations of O3 distributions and emissions trends to characterize the changing contributions of different source regions to background O3 levels across North America. This characterization of changing long-range transport contributions is critical for the design and implementation of tighter national air quality standards

Compilation of data from hadronic atoms

International Nuclear Information System (INIS)

Poth, H.

1979-01-01

This compilation is a survey of the existing data of hadronic atoms (pionic-atoms, kaonic-atoms, antiprotonic-atoms, sigmonic-atoms). It collects measurements of the energies, intensities and line width of X-rays from hadronic atoms. Averaged values for each hadronic atom are given and the data are summarized. The listing contains data on 58 pionic-atoms, on 54 kaonic-atoms, on 23 antiprotonic-atoms and on 20 sigmonic-atoms. (orig./HB) [de

A general approach for cache-oblivious range reporting and approximate range counting

DEFF Research Database (Denmark)

Afshani, Peyman; Hamilton, Chris; Zeh, Norbert

2010-01-01

We present cache-oblivious solutions to two important variants of range searching: range reporting and approximate range counting. Our main contribution is a general approach for constructing cache-oblivious data structures that provide relative (1+ε)-approximations for a general class of range c...

Identification of long-range transport of air pollutants using a Potential Source Contribution Function in Baengyeong Island, Korea

Science.gov (United States)

Ban, J.; Park, T.; Atwood, S. A.; Soo, C. J.; Ahn, J.; Lee, T.

2017-12-01

To understand the influence of long-range transport, Potential Source Contribution Function (PSCF) analysis is widely used in many studies. PSCF is a region containing a source for a particular constituent estimated by looking at the percentage of back-trajectories that pass over that region which contain high concentrations of the constituent. Aerosol concentration, wind direction, wind speed and back trajectory from NOAA HYSPLIT model in Baengyeong Island were used as input data for PSCF to consider the retention time of aerosol. Non-refractory PM1 (NR-PM1) concentrations were measured by an Aerodyne High Resolution Time of Flight Aerosol Mass Spectrometer (HR-ToF-AMS) and meteorological variables were also measured in Baengnyeong Island, Korea during 2013 to 2015. We will investigate the influence of long-range transport and compare with AMS data from eastern China in November 2013. It will be provided the overview of long-range transport of NR-PM1 including inorganics and organics species to South Korea.

Southern montane populations did not contribute to the recolonization of West Siberian Plain by Siberian larch (Larix sibirica): a range-wide analysis of cytoplasmic markers.

Science.gov (United States)

Semerikov, Vladimir L; Semerikova, Svetlana A; Polezhaeva, Maria A; Kosintsev, Pavel A; Lascoux, Martin

2013-10-01

While many species were confined to southern latitudes during the last glaciations, there has lately been mounting evidence that some of the most cold-tolerant species were actually able to survive close to the ice sheets. The contribution of these higher latitude outposts to the main recolonization thrust remains, however, untested. In the present study, we use the first range-wide survey of genetic diversity at cytoplasmic markers in Siberian larch (Larix sibirica; four mitochondrial (mt) DNA loci and five chloroplast (cp) DNA SSR loci) to (i) assess the relative contributions of southern and central areas to the current L. sibirica distribution range; and (ii) date the last major population expansion in both L. sibirica and adjacent Larix species. The geographic distribution of cpDNA variation was uninformative, but that of mitotypes clearly indicates that the southernmost populations, located in Mongolia and the Tien-Shan and Sayan Mountain ranges, had a very limited contribution to the current populations of the central and northern parts of the range. It also suggests that the contribution of the high latitude cryptic refugia was geographically limited and that most of the current West Siberian Plain larch populations likely originated in the foothills of the Sayan Mountains. Interestingly, the main population expansion detected through Approximate Bayesian Computation (ABC) in all four larch species investigated here pre-dates the LGM, with a mode in a range of 220,000-1,340,000 years BP. Hence, L. sibirica, like other major conifer species of the boreal forest, was strongly affected by climatic events pre-dating the Last Glacial Maximum. © 2013 John Wiley & Sons Ltd.

Precision calculation of threshold {pi}{sup -}d scattering, {pi}N scattering lengths, and the GMO sum rule

Energy Technology Data Exchange (ETDEWEB)

Baru, V. [Institut fuer Theoretische Physik II, Ruhr-Universitaet Bochum, D-44870 Bochum (Germany); Institut fuer Kernphysik and Juelich Center for Hadron Physics, Forschungszentrum Juelich, D-52425 Juelich (Germany); Institute for Theoretical and Experimental Physics, B. Cheremushinskaya 25, 117218 Moscow (Russian Federation); Hanhart, C. [Institut fuer Kernphysik and Juelich Center for Hadron Physics, Forschungszentrum Juelich, D-52425 Juelich (Germany); Institute for Advanced Simulation, Forschungszentrum Juelich, D-52425 Juelich (Germany); Hoferichter, M., E-mail: hoferichter@hiskp.uni-bonn.de [Helmholtz-Institut fuer Strahlen- und Kernphysik and Bethe Center for Theoretical Physics, Universitaet Bonn, D-53115 Bonn (Germany); Institute of Nuclear and Particle Physics and Department of Physics and Astronomy, Ohio University, Athens, OH 45701 (United States); Kubis, B. [Helmholtz-Institut fuer Strahlen- und Kernphysik and Bethe Center for Theoretical Physics, Universitaet Bonn, D-53115 Bonn (Germany); Nogga, A. [Institut fuer Kernphysik and Juelich Center for Hadron Physics, Forschungszentrum Juelich, D-52425 Juelich (Germany); Institute for Advanced Simulation, Forschungszentrum Juelich, D-52425 Juelich (Germany)

2011-12-15

We use chiral perturbation theory (ChPT) to calculate the {pi}{sup -}d scattering length with an accuracy of a few percent, including isospin-violating corrections in both the two- and three-body sectors. In particular, we provide the technical details of a recent letter (Baru et al., 2011) , where we used data on pionic deuterium and pionic hydrogen atoms to extract the isoscalar and isovector pion-nucleon scattering lengths a{sup +} and a{sup -}. We study isospin-breaking contributions to the three-body part of a{sub {pi}}{sup -}{sub d} due to mass differences, isospin violation in the {pi}N scattering lengths, and virtual photons. This last class of effects is ostensibly infrared enhanced due to the smallness of the deuteron binding energy. However, we show that the leading virtual-photon effects that might undergo such enhancement cancel, and hence the standard ChPT counting provides a reliable estimate of isospin violation in a{sub {pi}}{sup -}{sub d} due to virtual photons. Finally, we discuss the validity of the Goldberger-Miyazawa-Oehme sum rule in the presence of isospin violation, and use it to determine the charged-pion-nucleon coupling constant.

Hadronic vacuum polarization in true muonium

Science.gov (United States)

Lamm, Henry

2017-01-01

In order to reduce the theoretical uncertainty in the prediction, the leading-order hadronic vacuum polarization contribution to the hyperfine splitting of true muonium is reevaluated in two ways. A more complex pionic form factor and better estimates of the perturbative QCD contributions are used to study the model dependence of the previous calculation. The second, more accurate method directly integrates the Drell ratio R (s ) to obtain C1 ,HVP=-0.04874 (9 ) . This corresponds to an energy shift in the hyperfine splitting (HFS) of Δ EHFS,HVP μ=-8202 (16 ) MHz and represents a factor-of-50 reduction in the theoretical uncertainty from hadronic sources. We also compute the contribution in positronium, which is too small at present to detect.

Extremal problems in the phenomenology of the pion electromagnetic form factor

International Nuclear Information System (INIS)

Raszillier, I.

1977-09-01

The sets in Euclidean spaces are determined, which are the images of the mappings, performed by certain systems of functionals, from a set Ω in the Hilbert space H 2 of functions analytic in the unit disk. These sets express the correlations established by the elements of Ω between the functionals of the systems. Physically they give, for the functionals chosen, the correlation by experimental data between the pion charge radius, the pionic contribution to the muon magnetic moment and an Euclidean (or equivalent Chebyshev) measure of errors. (author)

Extracting the σ-term from low-energy pion-nucleon scattering

Science.gov (United States)

Ruiz de Elvira, Jacobo; Hoferichter, Martin; Kubis, Bastian; Meißner, Ulf-G.

2018-02-01

We present an extraction of the pion-nucleon (π N) scattering lengths from low-energy π N scattering, by fitting a representation based on Roy-Steiner equations to the low-energy data base. We show that the resulting values confirm the scattering-length determination from pionic atoms, and discuss the stability of the fit results regarding electromagnetic corrections and experimental normalization uncertainties in detail. Our results provide further evidence for a large π N σ-term, {σ }π N=58(5) {{MeV}}, in agreement with, albeit less precise than, the determination from pionic atoms.

Modelling the Contribution of Long-range Transport of Ammonium Nitrates to Urban Air Pollution and Human Exposure in the United Kingdom

Science.gov (United States)

Reis, S.; Vieno, M.; Beck, R.; Ots, R.; Moring, A.; Steinle, S.; Heal, M. R.; Doherty, R. M.

2014-12-01

Urban air pollution and its effects on human health remain to be a challenge in spite of substantial reductions in the emissions of air pollutants (e.g. sulphur dioxide, nitrogen oxides) over the past decades in Europe. While primary pollutants play a vital role in urban air pollution, recent model studies highlight and quantify the relevance of long-range transport of secondary pollution (e.g. secondary inorganic aerosols such as ammonium sulphates and nitrates, or ground level ozone) for the exceedance of local air quality limit values in urban areas across Europe. This contribution can be seen in recurring episodes, for instance in spring 2014, with very high levels of fine particulate matter (PM2.5) in Paris, London and other European cities, as well as in elevated background levels throughout the year. While we will focus on the contribution to exceedances of PM2.5 limit values here, this transboundary transport has wider implications for the deposition of reactive nitrogen far from the source as well. As local authorities are tasked with ensuring the attainment of air quality limit values, exceedances caused by long-range transport, with emissions originating from sources outside of their jurisdiction present substantial challenges. Furthermore, while policy measures have successfully addressed emissions from large point sources in the past, and made progress towards reducing pollution from road vehicles, emissions of ammonia from agricultural sources - a key component for the long-range transport of secondary inorganic aerosols - have remained relatively stable in Europe. Using the example of Europe and the UK, we demonstrate in our presentation how atmospheric chemistry transport modelling across different scales (from regional to local) can provide vital insight in the mechanisms of and relative contributions to the formation of secondary inorganic aerosols. In addition, we illustrate how this modelling capability can inform the design of efficient control

Estimation of the local and long-range contributions to particulate matter levels using continuous measurements in a single urban background site

Science.gov (United States)

Diamantopoulou, Marianna; Skyllakou, Ksakousti; Pandis, Spyros N.

2016-06-01

The Particulate Matter Source Apportionment Technology (PSAT) algorithm is used together with PMCAMx, a regional chemical transport model, to develop a simple observation-based method (OBM) for the estimation of local and regional contributions of sources of primary and secondary pollutants in urban areas. We test the hypothesis that the minimum of the diurnal average concentration profile of the pollutant is a good estimate of the average contribution of long range transport levels. We use PMCAMx to generate "pseudo-observations" for four different European cities (Paris, London, Milan, and Dusseldorf) and PSAT to estimate the corresponding "true" local and regional contributions. The predictions of the proposed OBM are compared to the "true" values for different definitions of the source area. During winter, the estimates by the OBM for the local contributions to the concentrations of total PM2.5, primary pollutants, and sulfate are within 25% of the "true" contributions of the urban area sources. For secondary organic aerosol the OBM overestimates the importance of the local sources and it actually estimates the contributions of sources within 200 km from the receptor. During summer for primary pollutants and cities with low nearby emissions (ratio of emissions in an area extending 100 km from the city over local emissions lower than 10) the OBM estimates correspond to the city emissions within 25% or so. For cities with relatively high nearby emissions the OBM estimates correspond to emissions within 100 km from the receptor. For secondary PM2.5 components like sulfate and secondary organic aerosol the OBM's estimates correspond to sources within 200 km from the receptor. Finally, for total PM2.5 the OBM provides approximately the contribution of city emissions during the winter and the contribution of sources within 100 km from the receptor during the summer.

A phenomenological π-p scattering length from pionic hydrogen

International Nuclear Information System (INIS)

Ericson, T.E.O.; Loiseau, B.; Wycech, S.

2004-01-01

We derive a closed, model independent, expression for the electromagnetic correction factor to a phenomenological hadronic scattering length a h extracted from a hydrogenic atom. It is obtained in a non-relativistic approach and in the limit of a short ranged hadronic interaction to terms of order α 2 logα using an extended charge distribution. A hadronic πN scattering length a h π - p =0.0870(5)m π -1 is deduced leading to a πNN coupling constant from the GMO relation g c 2 /(4π)=14.04(17)

A phenomenological $\\pi^{-}p$ scattering length from pionic hydrogen

CERN Document Server

Ericson, Torleif Eric Oskar; Wycech, S

2004-01-01

We derive a closed, model independent, expression for the electromagnetic correction factor to a phenomenological hadronic scattering length a/sup h/ extracted from a hydrogenic atom. It is obtained in a non-relativistic approach and in the limit of a short ranged hadronic interaction to terms of order alpha /sup 2/ log alpha using an extended charge distribution. A hadronic pi N scattering length a/sub pi -p//sup h/ = 0.0870(5)m/sub pi //sup -1/ is deduced leading to a pi NN coupling constant from the GMO relation g/sub c //sup 2//(4 pi ) = 14.04(17). (28 refs).

Pionic retardation effects in two-pion-exchange three-nucleon forces

International Nuclear Information System (INIS)

Coon, S.A.; Friar, J.L.

1986-01-01

Those two-pion-exchange three-nucleon forces which arise from nuclear processes that involve only pions and nucleons are calculated. Among the processes which contribute are pion seagulls (e.g., nucleon-antinucleon pair terms) and overlapping, retarded pion exchanges. The resulting potential is shown to be a (v/c) 2 relativistic correction, and satisfies nontrivial constraints from special relativity. The relativistic ambiguities found before in treatments of relativistic corrections to the one-pion-exchange nuclear charge operator and two-body potential are also present in the three-nucleon potential. The resulting three-nucleon force differs from the original Tucson-Melbourne potential only in the presence of several new nonlocal terms, and in the specification of the choice of ambiguity parameters in the latter potential

Pionic retardation effects in two-pion-exchange three-nucleon forces

Science.gov (United States)

Coon, S. A.; Friar, J. L.

1986-09-01

Those two-pion-exchange three-nucleon forces which arise from nuclear processes that involve only pions and nucleons are calculated. Among the processes which contribute are pion seagulls (e.g., nucleon-antinucleon pair terms) and overlapping, retarded pion exchanges. The resulting potential is shown to be a (v/c)2 relativistic correction, and satisfies nontrivial constraints from special relativity. The relativistic ambiguities found before in treatments of relativistic corrections to the one-pion-exchange nuclear charge operator and two-body potential are also present in the three-nucleon potential. The resulting three-nucleon force differs from the original Tucson-Melbourne potential only in the presence of several new nonlocal terms, and in the specification of the choice of ambiguity parameters in the latter potential.

Pionic retardation effects in two-pion-exchange three-nucleon forces

Energy Technology Data Exchange (ETDEWEB)

Coon, S.A.; Friar, J.L.

1986-09-01

Those two-pion-exchange three-nucleon forces which arise from nuclear processes that involve only pions and nucleons are calculated. Among the processes which contribute are pion seagulls (e.g., nucleon-antinucleon pair terms) and overlapping, retarded pion exchanges. The resulting potential is shown to be a (v-italic/c-italic)/sup 2/ relativistic correction, and satisfies nontrivial constraints from special relativity. The relativistic ambiguities found before in treatments of relativistic corrections to the one-pion-exchange nuclear charge operator and two-body potential are also present in the three-nucleon potential. The resulting three-nucleon force differs from the original Tucson-Melbourne potential only in the presence of several new nonlocal terms, and in the specification of the choice of ambiguity parameters in the latter potential.

Deeply bound π- states in 207Pb formed in the 208Pb(d,3He) reaction. II. Deduced binding energies and widths and the pion-nucleus interaction

Science.gov (United States)

Itahashi, K.; Oyama, K.; Hayano, R. S.; Gilg, H.; Gillitzer, A.; Knülle, M.; Münch, M.; Schott, W.; Kienle, P.; Geissel, H.; Iwasa, N.; Münzenberg, G.; Hirenzaki, S.; Toki, H.; Yamazaki, T.

2000-08-01

We find a remarkable agreement of the excitation energy spectrum of the 208Pb(d,3He) reaction measured at Td=600 MeV near the π- production threshold with its theoretical prediction. Their comparison leads us to assign the distinct narrow peak observed at about 5 MeV below the threshold to the formation of bound pionic states π-⊗207Pb of the quasisubstitutional configurations (2p)π-(3p3/2,3p1/2)-1n. A small bump observed on the tail of the peak is assigned to the pionic 1s state. The binding energies (Bnl) and the widths (Γnl) of the pionic orbitals are deduced to be B2p=5.13+/-0.02 (stat)+/-0.12 (syst) MeV and Γ2p=0.43+/-0.06 (stat)+/-0.06 (syst) MeV by decomposing the experimental spectrum into the pionic 1s and 2p components. While B2p and Γ2p are determined with small ambiguity, B1s and Γ1s are strongly correlated with each other, and are affected by the relative 1s/2p cross section ratio assumed, since the 1s component is observed only as an unresolved bump. Thus, we have to allow large uncertainties 6.6 MeV

On the chemistry of the lightest exotic atoms

International Nuclear Information System (INIS)

Horvath, D.

1980-01-01

The chemical aspects of formation of three hydrogen-like exotic atoms, positronium, muonium and pionic hydrogen are discussed. For positronium two formation mechanisms, the Ore model with hot-atom reactions, and the spur reaction model are set against experimental observations in solutions. The use of pionic hydrogen atoms in obtaining information on the bond properties of hydrogen is illustrated by recent experiments performed in JINR. The use of negative pions in chemistry is demonstrated by electronic structure investigations performed in Dubna. The probability W that in a chemical system containing bound hydrogen atoms a stopped negative pion is captured by a proton reflects the bond properties of hydrogen. Recent results haVe shown that the hydrogen bond formation in liquid water and the coordination of water molecules in aquacomplexes lead to significant decreases in probability W for water. A comparison of the chemical uses of the exotic atoms shows that positronium and muonium inform us on intermolecular level probing a small environment of a few molecules while the pionic hydrogen atoms deliver information on the chemical bond of hydrogen, i.e. on intramolecular level

Precision calculation of the {pi}{sup -}d scattering length and its impact on threshold {pi}N scattering

Energy Technology Data Exchange (ETDEWEB)

Baru, V. [Institut fuer Kernphysik and Juelich Center for Hadron Physics, Forschungszentrum Juelich, D-52425 Juelich (Germany); Institute for Theoretical and Experimental Physics, B. Cheremushinskaya 25, 117218 Moscow (Russian Federation); Hanhart, C. [Institut fuer Kernphysik and Juelich Center for Hadron Physics, Forschungszentrum Juelich, D-52425 Juelich (Germany); Institute for Advanced Simulation, Forschungszentrum Juelich, D-52425 Juelich (Germany); Hoferichter, M.; Kubis, B. [Helmholtz-Institut fuer Strahlen- und Kernphysik and Bethe Center for Theoretical Physics, Universitaet Bonn, D-53115 Bonn (Germany); Nogga, A. [Institut fuer Kernphysik and Juelich Center for Hadron Physics, Forschungszentrum Juelich, D-52425 Juelich (Germany); Institute for Advanced Simulation, Forschungszentrum Juelich, D-52425 Juelich (Germany); Phillips, D.R., E-mail: phillips@phy.ohiou.ed [Helmholtz-Institut fuer Strahlen- und Kernphysik and Bethe Center for Theoretical Physics, Universitaet Bonn, D-53115 Bonn (Germany); Institute of Nuclear and Particle Physics and Department of Physics and Astronomy, Ohio University, Athens, OH 45701 (United States)

2011-01-03

We present a calculation of the {pi}{sup -}d scattering length with an accuracy of a few percent using chiral perturbation theory. For the first time isospin-violating corrections are included consistently. Using data on pionic deuterium and pionic hydrogen atoms, we extract the isoscalar and isovector pion-nucleon scattering lengths and obtain a{sup +}=(7.6{+-}3.1).10{sup -3}M{sub {pi}}{sup -1} and a{sup -}=(86.1{+-}0.9).10{sup -3}M{sub {pi}}{sup -1}. Via the Goldberger-Miyazawa-Oehme sum rule, this leads to a charged-pion-nucleon coupling constant g{sub c}{sup 2}/4{pi}=13.69{+-}0.20.

Inbreeding in Gredos mountain range (Spain): contribution of multiple consanguinity and intervalley variation.

Science.gov (United States)

Fuster, V; Jiménez, A M; Colantonio, S E

2001-04-01

The present paper examines consanguineous marriages occurring between 1874 and 1975 in three valleys (Tormes, Alberche, and Tiétar) in the Sierra de Gredos mountain range, Avila province, Spain. Information was obtained from parish registers of 42 localities, corresponding to a total of 41,696 weddings. Consanguineous marriages were defined as those up to the third degree of consanguinity (second cousins). From 1874 to 1975 the percentage of related mates was 4.45% and the inbreeding coefficient was 0.0011868 (for 1874 to 1917 corresponding figures up to the fourth degree were 16.44% and 0.00 19085, respectively). In order to ascertain the characteristics and evolution of mating patterns in Gredos, the contribution of each degree of kinship was analyzed as a whole and then for each valley separately. Regarding total consanguineous marriages in Gredos, there is a low frequency of uncle-niece matings (0.21%) and a first-second cousin mating ratio (C22/C33) of 0.23 (up to the third degree of consanguinity). Before 1918 multiple matings (i.e., those involving more than a single relationship) accounted for 19.16% of consanguineous marriages (up to the fourth degree). The observed frequencies of multiple consanguineous marriages was, on average, about twice that expected at random, and the proportion of such marriages to total inbreeding was 34.65%. The temporal change of the Gredos inbreeding pattern was characterized by a recent decrease; the highest inbreeding levels correspond to the period from 1915 to 1944. Finally, intervalley differences (maximum inbreeding coefficient in the Tormes, minimum in the Tiétar) are interpreted considering the geography, population size, and population mobility for each valley

Review of recent experiments in intermediate energy nuclear physics

Energy Technology Data Exchange (ETDEWEB)

Barnes, P D [Carnegie-Mellon Univ., Pittsburgh, PA (USA)

1978-01-01

The data generated at intermediate-energy accelerator facilities has expanded rapidly over the past few years. A number of recent experiments chosen for their impact on nuclear structure questions are reviewed. Proton scattering together with pionic and muonic atom X-ray measurements are shown to be giving very precise determinations of gross nuclear properties. Pion scattering and reaction data although less precise, are starting to generate a new understanding of wave functions of specific nuclear states. Specific examples where new unpublished data are now available are emphasized. In addition, other medium-energy experiments that are starting to contribute to nuclear structure physics are summarized.

A phenomenological {pi}{sup -}p scattering length from pionic hydrogen

Energy Technology Data Exchange (ETDEWEB)

Ericson, T.E.O.; Loiseau, B.; Wycech, S

2004-07-29

We derive a closed, model independent, expression for the electromagnetic correction factor to a phenomenological hadronic scattering length a{sup h} extracted from a hydrogenic atom. It is obtained in a non-relativistic approach and in the limit of a short ranged hadronic interaction to terms of order {alpha}{sup 2}log{alpha} using an extended charge distribution. A hadronic {pi}N scattering length a{sup h}{sub {pi}{sup -}}{sub p}=0.0870(5)m{sub {pi}}{sup -1} is deduced leading to a {pi}NN coupling constant from the GMO relation g{sub c}{sup 2}/(4{pi})=14.04(17)

The contribution of microbunching instability to solar flare emission in the GHz to THz range of frequencies

Energy Technology Data Exchange (ETDEWEB)

Michael Klopf, J. [Department of Applied Science, College of William and Mary, McGlothlin-Street Hall, Williamsburg, VA 23187 (United States); Kaufmann, Pierre; Raulin, Jean-Pierre; Szpigel, Sérgio [Centro de Rádio-Astronomia e Astrofísica Mackenzie, Escola de Engenharia, Universidade Presbiteriana Mackenzie, Rua Consolação 896, São Paulo, SP 01302-907 (Brazil)

2014-08-10

Recent solar flare observations in the sub-terahertz range have provided evidence of a new spectral component with fluxes increasing for larger frequencies, separated from the well-known microwave emission that maximizes in the gigahertz range. Suggested interpretations explain the terahertz spectral component but do not account for the simultaneous microwave component. We present a mechanism for producing the observed 'double spectra'. Based on coherent enhancement of synchrotron emission at long wavelengths in laboratory accelerators, we consider how similar processes may occur within a solar flare. The instability known as microbunching arises from perturbations that produce electron beam density modulations, giving rise to broadband coherent synchrotron emission at wavelengths comparable to the characteristic size of the microbunch structure. The spectral intensity of this coherent synchrotron radiation (CSR) can far exceed that of the incoherent synchrotron radiation (ISR), which peaks at a higher frequency, thus producing a double-peaked spectrum. Successful CSR simulations are shown to fit actual burst spectral observations, using typical flaring physical parameters and power-law energy distributions for the accelerated electrons. The simulations consider an energy threshold below which microbunching is not possible because of Coulomb repulsion. Only a small fraction of the radiating charges accelerated to energies above the threshold is required to produce the microwave component observed for several events. The ISR/CSR mechanism can occur together with other emission processes producing the microwave component. It may bring an important contribution to microwaves, at least for certain events where physical conditions for the occurrence of the ISR/CSR microbunching mechanism are possible.

Contributions of biarticular myogenic components to the limitation of the range of motion after immobilization of rat knee joint

Science.gov (United States)

2014-01-01

Background Muscle atrophy caused by immobilization in the shortened position is characterized by a decrease in the size or cross-sectional area (CSA) of myofibers and decreased muscle length. Few studies have addressed the relationship between limitation of the range of motion (ROM) and the changes in CSA specifically in biarticular muscles after atrophy because of immobilization. We aimed to determine the contribution of 2 distinct muscle groups, the biarticular muscles of the post thigh (PT) and those of the post leg (PL), to the limitation of ROM as well as changes in the myofiber CSAs after joint immobilization surgery. Methods Male Wistar rats (n = 40) were randomly divided into experimental and control groups. In the experimental group, the left knee was surgically immobilized by external fixation for 1, 2, 4, 8, or 16 weeks (n = 5 each) and sham surgery was performed on the right knee. The rats in the control groups (n = 3 per time point) did not undergo surgery. After the indicated immobilization periods, myotomy of the PT or PL biarticular muscles was performed and the ROM was measured. The hamstrings and gastrocnemius muscles from the animals operated for 1 or 16 weeks were subjected to morphological analysis. Results In immobilized knees, the relative contribution of the PT biarticular myogenic components to the total restriction reached 80% throughout the first 4 weeks and decreased thereafter. The relative contribution of the PL biarticular myogenic components remained contracture did not significantly change during the experimental period. However, the ratio of hamstrings CSAs to the sham side was larger than the ratio of medial gastrocnemius CSAs to the sham side after complete atrophy because of immobilization. PMID:25001065

The new frontiers of electron scattering at intermediate energy

International Nuclear Information System (INIS)

Frois, B.

1984-08-01

Recent advances in experimental techniques have produced a new generation of electron scattering data. This paper explores the frontiers of this field and shows how our prospects for the future may be modified. Nuclear structure has been determined with an unprecedented accuracy defining clearly the limits of the most advanced theoretical descriptions. Large meson exchange currents are measured quantitatively with precision. Recent data on the electrodisintegration of deuterium at threshold and on the magnetic form factor of 3 He and tritium show that the pionic exchange current is well understood. There is no satisfactory theoretical description of shorter range processes

Pion-cloud corrections to the relativistic S + V harmonic potential model

International Nuclear Information System (INIS)

Palladino, B.E.; Ferreira, P.L.

1988-01-01

Pionic corrections to the mass spectrum of low-lying s-wave baryons are incorporated in a relativistic independent quark model with equally mixed Lorentz scalar and vector harmonic potentials. (M.W.O.) [pt

Strong and electromagnetic interactions in hadron systems

International Nuclear Information System (INIS)

Aissat, N.; Amghar, A.; Cano, F.; Gonzalez, F.; Noguera, S.; Carbonell, J.; Desplanques, B.; Silvestre-Brac, B.; Karmanov, V.; Mathiot, J.F.

1997-01-01

The pionic strong decay amplitudes of baryon resonances are studied in a constituent quark model. Particular attention is given to the operator describing the transition. The nucleon form factors are calculated in a non-relativistic approach, with emphasis on the highest momentum transfers. The aim is to determine the ingredients that are essential in getting correct results and are likely to be required for a more realistic estimate in a fully relativistic approach. The deuteron form factors have been calculated in the light-front approach using wave functions determined in a perturbative way. The derivation of the neutron charge form factor from the deuteron structure function, A(q 2 ), is reanalyzed including further mesonic exchange contributions. (authors)

Examining fluvial fish range loss with SDMs

Science.gov (United States)

Taylor, Andrew T.; Papeş, Monica; Long, James M.

2018-01-01

Fluvial fishes face increased imperilment from anthropogenic activities, but the specific factors contributing most to range declines are often poorly understood. For example, the range of the fluvial‐specialist shoal bass (Micropterus cataractae) continues to decrease, yet how perceived threats have contributed to range loss is largely unknown. We used species distribution models to determine which factors contributed most to shoal bass range loss. We estimated a potential distribution based on natural abiotic factors and a series of currently occupied distributions that incorporated variables characterizing land cover, non‐native species, and river fragmentation intensity (no fragmentation, dams only, and dams and large impoundments). We allowed interspecific relationships between non‐native congeners and shoal bass to vary across fragmentation intensities. Results from the potential distribution model estimated shoal bass presence throughout much of their native basin, whereas models of currently occupied distribution showed that range loss increased as fragmentation intensified. Response curves from models of currently occupied distribution indicated a potential interaction between fragmentation intensity and the relationship between shoal bass and non‐native congeners, wherein non‐natives may be favored at the highest fragmentation intensity. Response curves also suggested that >100 km of interconnected, free‐flowing stream fragments were necessary to support shoal bass presence. Model evaluation, including an independent validation, suggested that models had favorable predictive and discriminative abilities. Similar approaches that use readily available, diverse, geospatial data sets may deliver insights into the biology and conservation needs of other fluvial species facing similar threats.

Contribution of long-range interactions to the secondary structure of an unfolded globin.

Science.gov (United States)

Fedyukina, Daria V; Rajagopalan, Senapathy; Sekhar, Ashok; Fulmer, Eric C; Eun, Ye-Jin; Cavagnero, Silvia

2010-09-08

This work explores the effect of long-range tertiary contacts on the distribution of residual secondary structure in the unfolded state of an alpha-helical protein. N-terminal fragments of increasing length, in conjunction with multidimensional nuclear magnetic resonance, were employed. A protein representative of the ubiquitous globin fold was chosen as the model system. We found that, while most of the detectable alpha-helical population in the unfolded ensemble does not depend on the presence of the C-terminal region (corresponding to the native G and H helices), specific N-to-C long-range contacts between the H and A-B-C regions enhance the helical secondary structure content of the N terminus (A-B-C regions). The simple approach introduced here, based on the evaluation of N-terminal polypeptide fragments of increasing length, is of general applicability to identify the influence of long-range interactions in unfolded proteins. Copyright 2010 Biophysical Society. Published by Elsevier Inc. All rights reserved.

2011 NASA Range Safety Annual Report

Science.gov (United States)

Dumont, Alan G.

2012-01-01

Welcome to the 2011 edition of the NASA Range Safety Annual Report. Funded by NASA Headquarters, this report provides a NASA Range Safety overview for current and potential range users. As is typical with odd year editions, this is an abbreviated Range Safety Annual Report providing updates and links to full articles from the previous year's report. It also provides more complete articles covering new subject areas, summaries of various NASA Range Safety Program activities conducted during the past year, and information on several projects that may have a profound impact on the way business will be done in the future. Specific topics discussed and updated in the 2011 NASA Range Safety Annual Report include a program overview and 2011 highlights; Range Safety Training; Range Safety Policy revision; Independent Assessments; Support to Program Operations at all ranges conducting NASA launch/flight operations; a continuing overview of emerging range safety-related technologies; and status reports from all of the NASA Centers that have Range Safety responsibilities. Every effort has been made to include the most current information available. We recommend this report be used only for guidance and that the validity and accuracy of all articles be verified for updates. Once again the web-based format was used to present the annual report. We continually receive positive feedback on the web-based edition and hope you enjoy this year's product as well. As is the case each year, contributors to this report are too numerous to mention, but we thank individuals from the NASA Centers, the Department of Defense, and civilian organizations for their contributions. In conclusion, it has been a busy and productive year. I'd like to extend a personal Thank You to everyone who contributed to make this year a successful one, and I look forward to working with all of you in the upcoming year.

Pion-nuclear many body problems

International Nuclear Information System (INIS)

Weise, W.

1981-01-01

This chapter examines pion-nucleus scattering data produced at the meson factories in order to gain information about the ''optical'' branches of the pion-nuclear excitation spectrum. Discusses basic meson-baryon effective Lagrangians and elementary processes; pion-baryon vertex form factors; the spin-isospin dependent baryon-baryon interaction; pions in nuclear matter; nuclear spin-isospin correlations; the baryon-hole model; photon-induced excitation of baryon-hole states; high momentum transfer properties of pion-like nuclear states; a response function for pionic low-frequency modes in finite nuclei; and applications. Finds that there is no clear evidence for pionic critical opalescence, as in agreement with the expectation that the minimal density for the appearance of a pion condensate is certainly not lower than two or three times nuclear matter density

Theory of inclusive pionic reactions

International Nuclear Information System (INIS)

Oset, E.; Salcedo, L.L.; Strottman, D.

1985-01-01

A theory is developed for all the inclusive pion nuclear reactions, quasielastic, single charge exchange, double charge exchange and absorption, around the resonance region. The theory is based on the isobar hole model and makes an expansion in the number of particle-hole excitations. Up to 3p3h for pion absorption and 2p2h for quasielastic or charge exchange, where good convergence is found, are considered. The results obtained with this theory agree remarkably well with experiment for the different reactions and different nuclei in a wide region of energies around resonance

Compressed Data Structures for Range Searching

DEFF Research Database (Denmark)

Bille, Philip; Gørtz, Inge Li; Vind, Søren Juhl

2015-01-01

matrices and web graphs. Our contribution is twofold. First, we show how to compress geometric repetitions that may appear in standard range searching data structures (such as K-D trees, Quad trees, Range trees, R-trees, Priority R-trees, and K-D-B trees), and how to implement subsequent range queries...... on the compressed representation with only a constant factor overhead. Secondly, we present a compression scheme that efficiently identifies geometric repetitions in point sets, and produces a hierarchical clustering of the point sets, which combined with the first result leads to a compressed representation...

Pionic modes of excitation in continuum from the (p,n) reaction

International Nuclear Information System (INIS)

Izumoto, T.; Ichimura, M.; Ko, C.M.; Siemens, P.J.; Texas A and M Univ., College Station

1982-01-01

The continuum spectra of the 90 Zr(p, n) reaction at Esub(p) = 200 MeV are studied in the DWBA up to high excitation hω(approx. <= 60 MeV) and large momentum transfer q(approx. <= 3 μsub(π)). The response function is obtained in a local-density approximation, taking into account p-h and Δ-h excitations and the short-range correlation g' between them. For small g' approx. <= 0.5, a broad bump due to the opalescence effect can be seen in the calculated cross section at rather low excitation and near q approx. equal to 2.2 μsub(π). However, for larger g', this effect is suppressed, and a broader bump in cross section is located at higher excitation. (orig.)

Phase space overpopulation at CERN and possible explanations

International Nuclear Information System (INIS)

Pratt, S.

1998-01-01

By combining information from correlations from Pb+Pb collisions at CERN, one comes to the conclusion that pionic phase space is significantly overpopulated compared to expectations based on chemical equilibrium. A variety of explanations will be addressed. (author)

Rapid, facile synthesis of conjugated polymer zwitterions in ionic liquids

Energy Technology Data Exchange (ETDEWEB)

Page, Zachariah A. [Polymer Science & Engineering Department; Conte Center for Polymer Research; University of Massachusetts; Amherst, USA; Liu, Feng [Polymer Science & Engineering Department; Conte Center for Polymer Research; University of Massachusetts; Amherst, USA; Russell, Thomas P. [Polymer Science & Engineering Department; Conte Center for Polymer Research; University of Massachusetts; Amherst, USA; Emrick, Todd [Polymer Science & Engineering Department; Conte Center for Polymer Research; University of Massachusetts; Amherst, USA

2014-01-01

<p>Ionic liquids (ILs) were utilized for the rapid air-stable Suzuki polymerization of polar zwitterionic thiophene monomers, precluding the need for volatile organic solvents, phosphine ligands and phase transfer catalysts typically used in conjugated polymer synthesis.

Properties of short-range and long-range correlation energy density functionals from electron-electron coalescence

International Nuclear Information System (INIS)

Gori-Giorgi, Paola; Savin, Andreas

2006-01-01

The combination of density-functional theory with other approaches to the many-electron problem through the separation of the electron-electron interaction into a short-range and a long-range contribution is a promising method, which is raising more and more interest in recent years. In this work some properties of the corresponding correlation energy functionals are derived by studying the electron-electron coalescence condition for a modified (long-range-only) interaction. A general relation for the on-top (zero electron-electron distance) pair density is derived, and its usefulness is discussed with some examples. For the special case of the uniform electron gas, a simple parametrization of the on-top pair density for a long-range only interaction is presented and supported by calculations within the ''extended Overhauser model.'' The results of this work can be used to build self-interaction corrected short-range correlation energy functionals

The contribution of epidemiology

NARCIS (Netherlands)

Brandt, P. van den; Voorrips, L.; Hertz-Picciotto, I.; Shuker, D.; Boeing, H.; Speijers, G.; Guittard, C.; Kleiner, J.; Knowles, M.; Wolk, A.; Goldbohm, A.

2002-01-01

Epidemiologic studies directly contribute data on risk (or benefit) in humans as the investigated species, and in the full food intake range normally encountered by humans. This paper starts with introducing the epidemiologic approach, followed by a discussion of perceived differences between

Charged pion coherent production in nucleus-nucleus collisions at incident energies between 86 and 330 MeV/nucleon

International Nuclear Information System (INIS)

Fassnacht, P.

1984-01-01

We have studied pion production in nucleus-nucleus collisions at foward angles for about twenty projectile target combinations. The incident energies were below or around 300 MeV/nucleon which is the threshold of the elementary reaction NN → NNπ. The study of the inclusive spectra shows some new ideas: shell effects in pion production, collective resonances excitations. These spectra have been analyzed following different models: hard-scattering models which describe the interaction on the basis of the elementary reaction NN → NNπ, statistical model and the pionic cloud model which is a coherent description of the interaction. In the study of the exclusive reactions, we established some empiric rules concerning the cross-section variations. These exclusive spectra were then analyzed in the framework of two-models: the semi-phenomenological model and the pionic fusion [fr

σ and ρ meson strength distributions from in medium corrected ππ correlations and the nuclear equation of state

International Nuclear Information System (INIS)

Chanfray, G.; Aouissat, Z.; Schuck, P.; Norenberg, W.

1990-01-01

The most important part of the intermediate range nucleon-nucleon attraction is attributed to the exchange of non interacting as well as interaction two pions in the I = J = O channel. The corresponding 2π exchange potential, or part of it, is often simulated by a sigma-meson exchange with mass of about 600 MeV, which is then used as a basic input to nuclear matter calculation. This may give in particular a justification to the popular σ-ψ model. However a number of question remains concerning the microscopic nature of such an effective sigma meson. The point the authors want to emphasize in this paper concerns the possible modification of the sigma in the medium since they think that it is made out of pions whose propagations are strongly altered by the medium. However also the ρ-meson may undergo similar in medium corrections which possibly are related to recent experimental findings. The authors discuss, with a very simple model, the problem of pion propagation and pion-pion interaction in the medium and the occurrence of highly collective pion-delta modes (pionic branch, pisobar, quasi pion) in agreement with experimental data. They also should have some very important consequences on the dynamics of relativistic heavy collision. The authors address the very important question of the nuclear matter equation of state where collective pionic effects are included to reconstruct an effective sigma exchange whose mass and coupling constant are density dependent

Importance of the correlation contribution for local hybrid functionals: range separation and self-interaction corrections.

Science.gov (United States)

Arbuznikov, Alexei V; Kaupp, Martin

2012-01-07

Local hybrid functionals with their position-dependent exact-exchange admixture are a conceptually simple and promising extension of the concept of a hybrid functional. Local hybrids based on a simple mixing of the local spin density approximation (LSDA) with exact exchange have been shown to be successful for thermochemistry, reaction barriers, and a range of other properties. So far, the combination of this generation of local hybrids with an LSDA correlation functional has been found to give the most favorable results for atomization energies, for a range of local mixing functions (LMFs) governing the exact-exchange admixture. Here, we show that the choice of correlation functional to be used with local hybrid exchange crucially influences the parameterization also of the exchange part as well as the overall performance. A novel ansatz for the correlation part of local hybrids is suggested based on (i) range-separation of LSDA correlation into short-range (SR) and long-range (LR) parts, and (ii) partial or full elimination of the one-electron self-correlation from the SR part. It is shown that such modified correlation functionals allow overall larger exact exchange admixture in thermochemically competitive local hybrids than before. This results in improvements for reaction barriers and for other properties crucially influenced by self-interaction errors, as demonstrated by a number of examples. Based on the range-separation approach, a fresh view on the breakdown of the correlation energy into dynamical and non-dynamical parts is suggested.

Determination of the negatively charged pion-proton scattering length from pionic hydrogen

CERN Document Server

Ericson, Torleif Eric Oskar; Wycech, S

2003-01-01

We derive a closed, model independent, expression for the electromagnetic correction factor to the hadronic scattering length extracted from a hydrogenic atom with an extended charge and in the limit of a short ranged hadronic interaction to terms of order ((alpha)**2)(log(alpha)) in the limit of a non-relativistic approach. A hadronic negatively charged pion-proton scattering length of 0.0870(5), in units of inverse charged pion-mass, is deduced, leading to a pion-nucleon coupling constant from the GMO relation equals to 14.00(19).

Phase space overpopulation at CERN and possible explanations

International Nuclear Information System (INIS)

Pratt, S.

1999-01-01

Complete text of publication follows. By combining information from correlations from Pb+Pb collisions at CERN, one comes to the conclusion that pionic phase space is significantly overpopulated compared to expectations based on chemical equilibrium. A variety of explanations will be addressed. (author)

High-density native-range species affects the invasive plant Chromolaena odorata more strongly than species from its invasive range.

Science.gov (United States)

Zheng, Yulong; Liao, Zhiyong

2017-11-22

Invasive plant species often form dense mono-dominant stands in areas they have invaded, while having only sparse distribution in their native ranges, and the reasons behind this phenomenon are a key point of research in invasive species biology. Differences in species composition between native and invasive ranges may contribute to the difference in distribution status. In this study, we found that the high-density condition had a more negative effect on C. odorata than the low-density condition when co-grown with neighbor plants from its native range in Mexico, while this pattern was not in evidence when it was grown with neighbors from its invasive range in China. Different competitive ability and coevolutionary history with C. odorata between native-range neighbors and invasive-range neighbors may lead to the inconsistent patterns.

Drug: D01122 [KEGG MEDICUS

Lifescience Database Archive (English)

Full Text Available D01122 Drug Ibuprofen piconol (JP17/USAN); Staderm (TN) ... C19H23NO2 D01122.gif ... A...pionic acid derivative Active form of prodrug: Ibuprofen [DR:D00126] PTGS1 (COX1) [HSA:5742] [KO:K00509]; PT

Long-range antigravity

Energy Technology Data Exchange (ETDEWEB)

Macrae, K.I.; Riegert, R.J. (Maryland Univ., College Park (USA). Center for Theoretical Physics)

1984-10-01

We consider a theory in which fermionic matter interacts via long-range scalar, vector and tensor fields. In order not to be in conflict with experiment, the scalar and vector couplings for a given fermion must be equal, as is natural in a dimensionally reduced model. Assuming that the Sun is not approximately neutral with respect to these new scalar-vector charges, and if the couplings saturate the experimental bounds, then their strength can be comparable to that of gravity. Scalar-vector fields of this strength can compensate for a solar quadrupole moment contribution to Mercury's anomalous perihelion precession.

Long-range antigravity

International Nuclear Information System (INIS)

Macrae, K.I.; Riegert, R.J.

1984-01-01

We consider a theory in which fermionic matter interacts via long-range scalar, vector and tensor fields. In order not to be in conflict with experiment, the scalar and vector couplings for a given fermion must be equal, as is natural in a dimensionally reduced model. Assuming that the Sun is not approximately neutral with respect to these new scalar-vector charges, and if the couplings saturate the experimental bounds, then their strength can be comparable to that of gravity. Scalar-vector fields of this strength can compensate for a solar quadrupole moment contribution to Mercury's anomalous perihelion precession. (orig.)

Polarization in heavy-ion collisions: magnetic field and vorticity

Science.gov (United States)

Baznat, M.; Gudima, K.; Prokhorov, G.; Sorin, A.; Teryaev, O.; Zakharov, V.

2017-12-01

The polarization of hyperons due to axial chiral vortical effect is discussed. The effect is proportional to (strange) chemical potential and is pronounced at lower energies, contrary to that of magnetic field. The polarization of antihyperons has the same sign and larger magnitude. The emergence of vortical structures is observed in kinetic QGSM models. The hydrodynamical helicity separation receives the contribution of longitudinal velocity and vorticity implying the quadrupole structure of the latter. The transition from the quark vortical effects to baryons in confined phase may be achieved by exploring the axial charge. At the hadronic level the polarization corresponds to the cores of quantized vortices in pionic superfluid. The chiral vortical effects may be also studied in the frmework of Wigner function establishing the relation to the thermodynamical approach to polarization.

Vorticity and Λ polarization in baryon rich matter

Science.gov (United States)

Baznat, Mircea; Gudima, Konstantin; Prokhorov, George; Sorin, Alexander; Teryaev, Oleg; Zakharov, Valentin

2018-02-01

The polarization of Λ hyperons due to axial chiral vortical effect is discussed. The effect is proportional to (strange) chemical potential and is pronounced at lower energies in baryon-rich matter. The polarization of ¯ has the same sihn and larger magnitude. The emergence of vortical structures is observed in kinetic QGSM models. The hydrodynamical helicity separation receives the contribution of longitudinal velocity and vorticity implying the quadrupole structure of the latter. The transition from the quark vortical effects to baryons in confined phase may be achieved by exploring the axial charge. At the hadronic level the polarization corresponds to the cores of quantized vortices in pionic superfluid. The chiral vortical effects may be also studied in the frmework of Wigner function establishing the relation to the thermodynamical approach to polarization.

Exotic aspects of hadronic atoms-anomalous quasi-stabilities

International Nuclear Information System (INIS)

Yamazaki, Toshimitsu.

1993-07-01

Recently revealed, but hitherto unknown, new aspects of hadronic atoms, namely, anomalous quasi-stabilities of negative hadrons, are discussed. One is on long-lived antiprotonic helium atoms, characterized as 'atomic exotic halo' and the other is on deeply bound pionic atoms, characterized as 'nuclear exotic halo'. (author)

Widespread range expansions shape latitudinal variation in insect thermal limits

Science.gov (United States)

Lancaster, Lesley T.

2016-06-01

Current anthropogenic impacts, including habitat modification and climate change, may contribute to a sixth mass extinction. To mitigate these impacts and slow further losses of biodiversity, we need to understand which species are most at risk and identify the factors contributing to current and future declines. Such information is often obtained through large-scale, comparative and biogeographic analysis of lineages or traits that are potentially sensitive to ongoing anthropogenic change--for instance to predict which regions are most susceptible to climate change-induced biodiversity loss. However, for this approach to be generally successful, the underlying causes of identified geographical trends need to be carefully considered. Here, I augment and reanalyse a global data set of insect thermal tolerances, evaluating the contribution of recent and contemporary range expansions to latitudinal variation in thermal niche breadth. Previous indications that high-latitude ectotherms exhibit broad thermal niches and high warming tolerances held only for species undergoing range expansions or invasions. In contrast, species with stable or declining geographic ranges exhibit latitudinally decreasing absolute thermal tolerances and no latitudinal variation in tolerance breadths. Thus, non-range-expanding species, particularly insular or endemic species, which are often of highest conservation priority, are unlikely to tolerate future climatic warming at high latitudes.

Tonopah test range - outpost of Sandia National Laboratories

Energy Technology Data Exchange (ETDEWEB)

Johnson, L.

1996-03-01

Tonopah Test Range is a unique historic site. Established in 1957 by Sandia Corporation, Tonopah Test Range in Nevada provided an isolated place for the Atomic Energy Commission to test ballistics and non-nuclear features of atomic weapons. It served this and allied purposes well for nearly forty years, contributing immeasurably to a peaceful conclusion to the long arms race remembered as the Cold War. This report is a brief review of historical highlights at Tonopah Test Range. Sandia`s Los Lunas, Salton Sea, Kauai, and Edgewood testing ranges also receive abridged mention. Although Sandia`s test ranges are the subject, the central focus is on the people who managed and operated the range. Comments from historical figures are interspersed through the narrative to establish this perspective, and at the end a few observations concerning the range`s future are provided.

Determination of the pion-nucleon coupling constant and scattering lengths

CERN Document Server

Ericson, Torleif Eric Oskar; Thomas, A W

2002-01-01

We critically evaluate the isovector GMO sum rule for forward pion-nucleon scattering using the recent precision measurements of negatively charged pion-proton and pion-deuteron scattering lengths from pionic atoms. We deduce the charged-pion-nucleon coupling constant, with careful attention to systematic and statistical uncertainties. This determination gives, directly from data a pseudoscalar coupling constant of 14.17+-0.05(statistical)+-0.19(systematic) or a pseudovector one of 0.0786(11). This value is intermediate between that of indirect methods and the direct determination from backward neutron-proton differential scattering cross sections. We also use the pionic atom data to deduce the coherent symmetric and antisymmetric sums of the negatively charged pion-proton and pion-neutron scattering lengths with high precision. The symmetric sum gives 0.0017+-0.0002(statistical)+-0.0008 (systematic) and the antisymmetric one 0.0900+-0.0003(statistical)+-0.0013(systematic), both in units of inverse charged pi...

High energy spin isospin modes in nuclei

International Nuclear Information System (INIS)

Chanfray, G.; Ericson, M.

1984-01-01

The high energy response of nuclei to a spin-isospin excitation is investigated. We show the existence of a strong contrast between the spin transverse and spin longitudinal responses. The second one undergoes a shadow effect in the Δ region and displays the occurrence of the pionic branch

Pion content of the nucleon in polarized semi-inclusive DIS

Energy Technology Data Exchange (ETDEWEB)

Melnitchouk, W. [Univ. of Regensburg (Germany); Thomas, A.W. [Univ. of Adelaide (Australia)

1994-04-01

An explicit pionic component of the nucleon may be identified by measuring polarized {Delta}{sup ++} fragments produced in deep-inelastic scattering (DIS) off polarized protons. The pion-exchange model predicts highly correlated polarizations of the {Delta}{sup ++} and target proton, in marked contrast with the competing diquark fragmentation process.

Lowering of proton mass with respect to neutron state in g'-quark electromagnetic soliton theory: Pt. 1

International Nuclear Information System (INIS)

Lebrun, J.-P.M.

1988-01-01

The modification of electrodynamics for the g'-quark permitting chiral invariance, CA, and PCAC to hold effords to relate the nucleon electromagnetic mass splitting to the pionic case previously treated by Ward's identities. This gives correct sign and order of magnitude for his effect and finite positive proton charge

Shear Strength of Concrete I-Beams - Contributions of Flanges

DEFF Research Database (Denmark)

Teoh, B. K.; Hoang, Cao Linh; Nielsen, Mogens Peter

1999-01-01

The contribution of flanges to the shear strength of reinforced concrete beams has up to now either been neglected or evaluated by very simple empirical formulas. However, the contribution may sometimes be large, up to 20-30%. In this paper the flange contribution for shear reinforced I-beams has...... range of geometrical parameters. The comparisons show that the method suggested does indeed lead to very accurate results....

Hydrodynamic modeling of 3He–Au collisions at sNN=200 GeV

Directory of Open Access Journals (Sweden)

Piotr Bożek

2015-07-01

Full Text Available Collective flow and femtoscopy in ultrarelativistic 3He–Au collisions are investigated within the 3+1-dimensional (3+1D viscous event-by-event hydrodynamics. We evaluate elliptic and triangular flow coefficients as functions of the transverse momentum. We find the typical long-range ridge structures in the two-particle correlations in the relative azimuth and pseudorapidity, in the pseudorapidity directions of both Au and 3He. We also make predictions for the pionic interferometric radii, which decrease with the transverse momentum of the pion pair. All features found hint on collectivity of the dynamics of the system formed in 3He–Au collisions, with hydrodynamics leading to quantitative agreement with the up-to-now released data.

Japanese contributions to IAEA INTOR workshop, phase IIA

International Nuclear Information System (INIS)

Miyamoto, Kenro; Sugihara, Masayoshi; Kimura, Haruyuki

1982-11-01

This report corresponds to Chapter V of Japanese contribution report to IAEA INTOR workshop, Phase IIA. Physics studies for radio frequency heating are concentrated on heating to ignition by means of ion cyclotron and lower hybrid ranges of frequencies, and discharge start-up assist and current drive by lower hybrid range. Their system design studies are also performed. (author)

Magnetic moments of octet baryons in a chiral potential model

International Nuclear Information System (INIS)

Barik, N.

1986-01-01

Incorporating the lowest-order pionic correction, the magnetic moments of the nucleon octet have been calculated in a chiral potential model. The potential, representing phenomenologically the nonperturbative gluon self-couplings, is chosen with equally mixed scalar and vector parts in a power-law form. The results are in reasonable agreement with experiment. (author)

Magnetic moments of the nucleon octet in a relativistic quark model with chiral symmetry

International Nuclear Information System (INIS)

Barik, N.; Dash, B.K.

1986-01-01

Incorporating the lowest-order pionic correction, the magnetic moments of the nucleon octet have been calculated in a chiral potential model. The potential, representing phenomenologically the nonperturbative gluon interactions including gluon self-couplings, is chosen with equally mixed scalar and vector parts in harmonic form. The results are in reasonable agreement with experiment

Theoretical research in intermediate energy nuclear physics: Final report

International Nuclear Information System (INIS)

Seki, R.

1987-01-01

This paper discusses the progress that has been made on the following problems: a numerical calculation of Skyrmiron scattering; (e,e'p) at high momentum transfer; spin-orbit nucleon-nucleon potential from Skyrme model; pionic atom anomaly; and field theory problems. The problems deal with various topics in intermediate-energy nuclear physics

The contribution of technology to added value

CERN Document Server

Fernandes, António S C

2013-01-01

There is a wide consensus that introduction of technology to the production process contributes to an overall economic value, however, confusion between technology, knowledge and capital often makes value calculations ambiguous and non-objective. The Contribution of Technology to Added Value addresses not only this issue of definition but also provides a production model to assess the value contribution of technology within the production process. A clarification  of fundamental semantics  provides a significant taxonomy for technology dependence, and allows understanding and modeling of how knowledge, technology and capital individually contribute to production and to value adding. A new technology dependence taxonomy is proposed and assessed following chapters explaining growth models, the KTC model and technology index values. Balancing theoretical knowledge with real-world data and applications The Contribution of Technology to Added Value clarifies the issue of value adding for a range of different vie...

Development of the relativistic impulse approximation

International Nuclear Information System (INIS)

Wallace, S.J.

1985-01-01

This talk contains three parts. Part I reviews the developments which led to the relativistic impulse approximation for proton-nucleus scattering. In Part II, problems with the impulse approximation in its original form - principally the low energy problem - are discussed and traced to pionic contributions. Use of pseudovector covariants in place of pseudoscalar ones in the NN amplitude provides more satisfactory low energy results, however, the difference between pseudovector and pseudoscalar results is ambiguous in the sense that it is not controlled by NN data. Only with further theoretical input can the ambiguity be removed. Part III of the talk presents a new development of the relativistic impulse approximation which is the result of work done in the past year and a half in collaboration with J.A. Tjon. A complete NN amplitude representation is developed and a complete set of Lorentz invariant amplitudes are calculated based on a one-meson exchange model and appropriate integral equations. A meson theoretical basis for the important pair contributions to proton-nucleus scattering is established by the new developments. 28 references

Precise X-Ray spectroscopy of the hydrogenlike and heliumlike heavy ions and of the exotic atoms

International Nuclear Information System (INIS)

Manil, B.

2001-10-01

In this thesis, we present four experiments designed to study hydrogenlike and heliumlike heavy ions, or exotic atoms. These experiments have been run at the Gesellschaft fur Schwerionenforchung (GSI) and the Paul Scherrer Institut (PSI). In the first part of this text, we begin with the description of a focusing, curved-crystal spectrometer in transmission geometry, coupled with a microstrip, germanium position-sensitive detector, which diffract X-ray photons in the range 50-100 keV. With this spectrometer, which can be mounted on the GSI accelerator, we will increase, by one order of magnitude, the accuracy on the measurement of the 1 s Lamb shift in hydrogenlike uranium ions, in order to test QED in strong coulomb field. Next, we detail an experiment that will soon give a new value of the charged-pion mass with a relative accuracy of 1 ppm. For that, we perform X-ray spectroscopy of pionic nitrogen, at PSI. The experimental set-up is made up of a cyclotron trap, a spherical Bragg-crystal focusing spectrometer, in reflection geometry, and a CCD sensitive-position cooled detector. This set-up allows also test QCD and chiral perturbation theory by measurements of radiative transitions of pionic hydrogen. The main subject of the second part is a lifetime measurement of the metastable 2 3 P 0 state in heliumlike gold ions, by Beam Foil Spectroscopy. With this experiment, which provides an important test of relativistic many-body theory, we give, for the first time, an accurate value of the lifetime of this state for an ion with a Z larger than 64, our result is τ(exp) = (22.12 ± 1.21) ps

Angular dependence of the sup(6)Li(πsup(+),sup(3)He)sup(3)He reaction

International Nuclear Information System (INIS)

McParland, B.J.; Auld, E.G.; Couvert, P.

1985-02-01

Angular distributions of the differential cross sections for the pionic fission sup(6)Li(πsup(+),sup(3)He)sup(3)He have been measured at pion energies of 60 and 80 MeV. The differential cross section is found to decrease monotonically with cossup(2)thetasup(*) and is compared with a theoretical prediction

Emerging infectious diseases in free-ranging wildlife-Australian zoo based wildlife hospitals contribute to national surveillance.

Directory of Open Access Journals (Sweden)

Keren Cox-Witton

Full Text Available Emerging infectious diseases are increasingly originating from wildlife. Many of these diseases have significant impacts on human health, domestic animal health, and biodiversity. Surveillance is the key to early detection of emerging diseases. A zoo based wildlife disease surveillance program developed in Australia incorporates disease information from free-ranging wildlife into the existing national wildlife health information system. This program uses a collaborative approach and provides a strong model for a disease surveillance program for free-ranging wildlife that enhances the national capacity for early detection of emerging diseases.

The Range of Microbial Risks in Food Processing

NARCIS (Netherlands)

Zwietering, M.H.; Straver, J.M.; Asselt, van E.D.

2016-01-01

Foodborne illnesses can be caused by a wide range of microorganisms. Data analysis can help to determine which microorganisms give the highest contribution to the number of foodborne illnesses. This helps to decide which pathogen(s) to focus on in order to reduce the number of illnesses. The same

AN HISTORICAL OVERVIEW OF THE IMPORTANCE OF THE WEAK DECAY OF HYPERNUCLEI

International Nuclear Information System (INIS)

GIBSON, B.F.

2001-01-01

Weak decay of hypernuclei, first cousin to the β-decay of conventional, nonstrange nuclei, was initially observed in the 1950s. Pionic decay rates have proven a challenge--to reconcile nuclear decay rates with that of free λ decay. Pauli blocking of the decay nucleon plays an important role. Nonmesonic decay provides our only practical means of exploring the four-fermion, strangeness-changing NΛ → NN weak interaction. The NΛρ vertex can be investigated in no other way. The large momentum transfer in the nonmesonic decay process suggests a means to probe short distance aspects of the interaction, possibly revealing baryon substructure effects. Whether the ΔI = 1/2 rule, which governs free Λ decay, also applies to the nonmesonic decay process remains an open question. The free Λ does not decay by emission of a π + ; the π + decay of 4 He is a puzzle. Finally, the weak decay of strangeness -2 hypernuclei is an important topic, because the pionic decay process is central to current efforts to seek and identify ΛΛ hypernuclei

Precision determination of pion mass using X-ray CCD spectroscopy

CERN Document Server

Nelms, N; Augsburger, M A; Borchert, G; Chatellard, D; Daum, M; Egger, J P; Gotta, D; Hauser, P; Indelicato, P J; Jeannet, E; Kirch, K; Schult, O W B; Siems, T; Simons, L M; Wells, A

2002-01-01

An experiment is described which aims to determine the charged pion mass to 1 ppm or better, from which a new determination of the upper limit of the muon neutrino mass is anticipated. The experimental approach uses a high-intensity negative pion beam (produced at the PSI 590 MeV proton cyclotron), injected into a cyclotron trap and stopped inside a gas-filled target chamber, to form highly excited exotic atoms of pionic nitrogen and muonic oxygen. The energy of photons, emitted during de-excitation, is directly proportional to the mass of the pion or muon. These soft X-ray emission spectra are measured using a high-precision crystal spectrometer, with an array of six, high quantum efficiency X-ray position resolving CCDs at the focus. To achieve sub-ppm accuracy, simultaneous calibration of the pionic nitrogen line is provided by measurement of an adjacent muonic oxygen line, whose energy is known to 0.3 ppm. The high precision of the experiment offers a new opportunity to determine the pion mass to the leve...

Coplanarity of two-proton emissions in 400 MeV/nucleon Ne + NaF, Pb reactions

International Nuclear Information System (INIS)

Tanihata, Isao.

1984-10-01

Two-proton coincidence spectra have been measured in a wide kinematical range for 20 Ne + NaF and 20 Ne + Pb collisions at 400 MeV/nucleon. Coplanar-type correlations show different feature between Ne + NaF and Ne + Pb target reactions. A strong in-plane correlation, which correspond to quasi-elastic scatterings (QES) of nucleons, was observed in wide angular range (15 to 90 0 ) in NaF target collisions. Angular distributions of QES were reproduced reasonably well by a single nucleon-nucleon scattering model. Enhancement of the QES at momentum transfer around t = 2 - 3m/sub π/, which is predicted as an indication of pionic instability, was not observed. In Ne + Pb collisions, an azimuthally asymmetric emission of particles with respect to the beam axis were implied by the anti-coplanar correlation. A new type of coplanar correlation between the emission angle and the momentum suggests a back-to-back emission of projectile and target nucleons. 8 references, 8 figures

Intermediate-range order in lead metasilicate glass

Energy Technology Data Exchange (ETDEWEB)

Suzuya, Kentaro [Japan Atomic Energy Research Inst., Ako, Hyogo (Japan)]|[Argonne National Lab., IL (United States). Materials Science Div.; Price, D.L.; Saboungi, M.L. [Argonne National Lab., IL (United States). Materials Science Div.; Ohno, Hideo [Japan Atomic Energy Research Inst., Ako, Hyogo (Japan)

1997-03-01

The complementarity of anomalous X-ray scattering (AXS) and neutron diffraction (ND) techniques is used here to investigate the nature and origin of intermediate-range order in lead metasilicate glass. Both X-ray and neutron source factors reveal small peaks at low wave vector which are shown to be associated with intermediate-range order of the Pb-O network. The combination of AXS and ND is shown to be a powerful tool to correlate contributions from the different atom pairs to such a peak. The information thus derived is compared with results from alkali germanate glasses and with structural data on corresponding crystalline compounds.

A Group Contribution Method for Estimating Cetane and Octane Numbers

Energy Technology Data Exchange (ETDEWEB)

Kubic, William Louis [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Process Modeling and Analysis Group

2016-07-28

Much of the research on advanced biofuels is devoted to the study of novel chemical pathways for converting nonfood biomass into liquid fuels that can be blended with existing transportation fuels. Many compounds under consideration are not found in the existing fuel supplies. Often, the physical properties needed to assess the viability of a potential biofuel are not available. The only reliable information available may be the molecular structure. Group contribution methods for estimating physical properties from molecular structure have been used for more than 60 years. The most common application is estimation of thermodynamic properties. More recently, group contribution methods have been developed for estimating rate dependent properties including cetane and octane numbers. Often, published group contribution methods are limited in terms of types of function groups and range of applicability. In this study, a new, broadly-applicable group contribution method based on an artificial neural network was developed to estimate cetane number research octane number, and motor octane numbers of hydrocarbons and oxygenated hydrocarbons. The new method is more accurate over a greater range molecular weights and structural complexity than existing group contribution methods for estimating cetane and octane numbers.

Magnetic moments of octet baryons in a chiral potential model

Energy Technology Data Exchange (ETDEWEB)

Barik, N; Das, M

1986-12-01

Incorporating the lowest-order pionic correction, the magnetic moments of the nucleon octet have been calculated in a chiral potential model. The potential, representing phenomenologically the nonperturbative gluon self-couplings, is chosen with equally mixed scalar and vector parts in a power-law form. The results are in reasonable agreement with experiment. 32 refs., 2 tables.

Pramana – Journal of Physics | Indian Academy of Sciences

Indian Academy of Sciences (India)

Home; Journals; Pramana – Journal of Physics. Dipak Ghosh. Articles written in Pramana – Journal of Physics. Volume 63 Issue 5 November 2004 pp 963-968 Research Articles. Strong pionic intermittency in `cold' events in 12C–AgBr interactions at 4.5 A GeV · Dipak Ghosh Argha Deb Asok Kumar Mallik Sharmila Sarkar ...

Geographic range size and determinants of avian species richness

DEFF Research Database (Denmark)

Jetz, Walter; Rahbek, Carsten

2002-01-01

Geographic patterns in species richness are mainly based on wide-ranging species because their larger number of distribution records has a disproportionate contribution to the species richness counts. Here we demonstrate how this effect strongly influences our understanding of what determines spe...

Contribution to the study of the unresolved resonance range of the neutrons cross sections

International Nuclear Information System (INIS)

Noguere, Gilles

2014-01-01

This document presents the statistical description of neutron cross sections in the unresolved resonance range. The modeling of the total cross section and of the 'shape - elastic' cross section is based on the 'average R-Matrix' formalism. The partial cross sections describing the radiative capture, elastic scattering, inelastic scattering and fission process are calculated using the Hauser-Feshbach formalism with width fluctuation corrections. In the unresolved resonance range, these models depend on the average resonance parameters (neutron strength function Sc, mean level spacing D c , average partial reaction widths Γ c , channel radius a c , effective radius R' and distant level parameter R-bar c ∞ ). The codes (NJOY, CALENDF...) dedicated to the processing of nuclear data libraries (JEFF, ENDF/B, JENDL, CENDL, BROND... ) use the average parameters to take into account the self-shielding phenomenon for the simulation of the neutron transport in Monte-Carlo (MCNP, TRIPOLI... ) and deterministic (APOLLO, ERANOS...) codes. The evaluation work consists in establishing a consistent set of average parameters as a function of the total angular momentum J of the system and of the orbital moment of the incident neutron l. The work presented in this paper aims to describe the links between the S-Matrix and the 'average R-Matrix' formalism for the calculation of Sc, R-bar c ∞ , ac and R'. (author) [fr

Contribution of long-range transport to the ozone levels recorded in the Northeast of Portugal

Science.gov (United States)

Gama, C.; Nunes, T.; Marques, M. C.; Ferreira, F.

2009-04-01

levels were calculated for each cluster and the differences between the groups were validated using the Kruskal-Wallis statistical test. The results have shown a significant influence of the transport path on ozone concentrations, which is more noticeable when the probability of occurring photochemical pollution phenomena is higher. Air masses from Europe (Spain, France, United Kingdom, etc.) generally originate higher ozone levels than the ones arriving from the Atlantic Ocean. This feature shows the role of photochemical production along long-range transport phenomena, and the input of pollutants into air masses, along their path. A more detailed analysis at local/regional scale, supported mainly by an intensive field campaign performed during spring/summer of 2006 in the vicinity of Alvão Natural Park (FOTONET Project), at different altitudes, together with pollutant measurements from rural air quality stations in the north of Portugal and one from Spain (Peñausende) was carried out in order to evaluate the extension of photochemical pollution in the Northeast of Portugal. Ozone concentrations measurements in the region showed a noticeable decrease with altitude, mainly at night. In resume back trajectories based analysis has demonstrated that other countries, mainly Spain, contribute decisively to the ozone levels registered in the station used for this study. Backed on this knowledge we point out towards the need of considering common international policies when dealing with controlling ozone levels in the environment. References: Monks, P. (2000): A review of the observations and origins of the spring ozone maximum. Atmospheric Environment 34, 3545-3561. Vingarzan, R., Taylor, B. (2003): Trend analysis of ground level ozone in the greater Vancouver / Fraser Valley area of British Columbia. Atmospheric Environment 37, 2159-2171. EMPA (2008): Air mass trajectory clustering. Retrieved 01 November 2008 from: http://www.empa.ch/plugin/template/empa/*/63288/—/l=1

Sir Clive Granger’s contributions to nonlinear time series and econometrics

DEFF Research Database (Denmark)

Terasvirta, Timo

Clive Granger had a wide range of reseach interests and has worked in a number of areas. In this work the focus is on his contributions to nonlinear time series models and modelling. Granger's contributions to a few other aspects of nonlinearity are reviewed as well....

Mean free path dependent phonon contributions to interfacial thermal conductance

Energy Technology Data Exchange (ETDEWEB)

Tao, Yi; Liu, Chenhan; Chen, Weiyu; Cai, Shuang; Chen, Chen; Wei, Zhiyong; Bi, Kedong; Yang, Juekuan; Chen, Yunfei, E-mail: yunfeichen@seu.edu.cn

2017-06-15

Interfacial thermal conductance as an accumulation function of the phonon mean free path is rigorously derived from the thermal conductivity accumulation function. Based on our theoretical model, the interfacial thermal conductance accumulation function between Si/Ge is calculated. The results show that the range of mean free paths (MFPs) for phonons contributing to the interfacial thermal conductance is far narrower than that for phonons contributing to the thermal conductivity. The interfacial thermal conductance is mainly contributed by phonons with shorter MFPs, and the size effects can be observed only for an interface constructed by nanostructures with film thicknesses smaller than the MFPs of those phonons mainly contributing to the interfacial thermal conductance. This is why most experimental measurements cannot detect size effects on interfacial thermal conductance. A molecular dynamics simulation is employed to verify our proposed model. - Highlights: • A model to account for the interfacial thermal conductance as an accumulation function of phonon mean free path is proposed; • The model predicts that the range of mean free paths (MFPs) for phonons contributing to the interfacial thermal conductance is far narrower than that contributing to the thermal conductivity; • This model can be conveniently implemented to estimate the size effects on the interfacial thermal conductance for the interfaces formed by a nanostructure contacting a substrate.

Northward dispersal of sea kraits (Laticauda semifasciata beyond their typical range.

Directory of Open Access Journals (Sweden)

Jaejin Park

Full Text Available Marine reptiles are declining globally, and recent climate change may be a contributing factor. The study of sea snakes collected beyond their typical distribution range provides valuable insight on how climate change affects marine reptile populations. Recently, we collected 12 Laticauda semifasciata (11 females, 1 male from the waters around southern South Korea-an area located outside its typical distribution range (Japan, China including Taiwan, Philippines and Indonesia. We investigated the genetic origin of Korean specimens by analyzing mitochondrial cytochrome b gene (Cytb sequences. Six individuals shared haplotypes with a group found in Taiwan-southern Ryukyu Islands, while the remaining six individuals shared haplotypes with a group encompassing the entire Ryukyu Archipelago. These results suggest L. semifasciata moved into Korean waters from the Taiwan-Ryukyu region via the Taiwan Warm Current and/or the Kuroshio Current, with extended survival facilitated by ocean warming. We highlight several contributing factors that increase the chances that L. semifasciata establishes new northern populations beyond the original distribution range.

Low equation, pion-nucleon scattering, and Castillejo-Dalitz-Dyson pole

International Nuclear Information System (INIS)

Nakano, K.; Nogami, Y.

1986-01-01

We examine the p-wave πN scattering at medium energies by means of the Low equation with a view to determining the form factor of the πN interaction. Solutions of the equation with and without a Castillejo-Dalitz-Dyson (CDD) pole are used. The solution with no CDD pole corresponds to the old Chew-Low model, whereas the one with a CDD pole corresponds to the quark version of the Chew-Low model. The πN interaction form factor is determined so that the Δ resonance is well reproduced. We find that the solution with a CDD pole leads to a softer form factor but is not as soft as those expected from the nucleon size in the quark model. Using the solutions and form factors thus determined, we also examine the pionic contributions to the nucleon magnetic moment and the nucleon mass

Proprioceptive acuity into knee hypermobile range in children with Joint Hypermobility Syndrome

OpenAIRE

Pacey, Verity; Adams, Roger D; Tofts, Louise; Munns, Craig F; Nicholson, Leslie L

2014-01-01

Background Children with Joint Hypermobility Syndrome (JHS) have reduced knee joint proprioceptive acuity compared to peers. Altered proprioception at end of range in individuals with JHS is hypothesised to contribute to recurrent joint injuries and instability. This study aims to provide the first objective comparison of functional knee joint proprioceptive acuity in hyperextension range compared to early flexion range in children with JHS. Methods Active, weight-bearing knee joint proprioce...

Contribution of the reverse endoprosthesis to glenohumeral kinematics.

OpenAIRE

Bergmann, J.H.M.; de Leeuw, M.; Janssen, T.W.J.; Veeger, H.E.J.; Willems, W.J.

2008-01-01

After placement of a reverse shoulder endoprosthesis, range of motion is usually still compromised. To what extent this occurs from limitation in motion of the reverse endoprosthesis is, however, unclear. We measured the motion pattern of 16 patients (18 shoulders) during three active and passive range of motion tasks using a six degree-of-freedom electromagnetic tracking device. Despite rotator cuff deficiencies, glenohumeral elevation contributed roughly two-thirds of the total thoracohumer...

Physics at the AD/PS/SPS - PLEASE NOTE CHANGE OF ROOM!(2/4)

CERN Multimedia

CERN. Geneva

2012-01-01

Lecture 2: QCD and hadron physics: COMPASS, NA61, DIRAC The lecture will discuss the research done at the COMPASS, SHINE and DIRAC experiments at the SPS and PS. COMPASS studies nucleon structure and hadron spectroscopy, SHINE searches for the critical point and onset of deconfinement in heavy ion collisions while DIRAC studies the pi-pi scattering length in pionic atoms.

An Enquiry Concerning Charmless Semileptonic Decays of Bottom Mesons

Energy Technology Data Exchange (ETDEWEB)

Chaisanguanthum, Kris Somboon [Harvard Univ., Cambridge, MA (United States)

2008-05-01

The branching fractions for the decays B → Pℓv_ℓ, where P are the pseudoscalar charmless mesons π^±, π⁰, η and η' and ℓ is an electron or muon, are measured with B⁰ and B^± mesons found in the recoil of a second B meson decaying as B → Dℓv_ℓ or B → D*ℓv_ℓ. The measurements are based on a data set of 348 fb^-1 of e⁺e^- collisions at √s = 10.58 GeV recorded with the BABAR detector. Assuming isospin symmetry, measured pionic branching fractions are combined into β(B⁰ → π^-ℓ⁺v_ℓ) = (1.54 ± 0.17_(stat) ± 0.09_(syst)) x 10^-4. First evidence of the B⁺ → ηℓ⁺v_ℓ decay is seen; its branching fraction is measured to be β(B⁺ →ηℓ⁺v_ℓ) = (0.64 ± 0.20_(stat) ± 0.03_(syst)) x 10^-4. It is determined that β(B⁺ → η'ℓ⁺v_ℓ) < 0.47 x 10^-4 to 90% confidence. Partial branching fractions for the pionic decays in ranges of the momentum transfer and various published calculations of the B → π hadronic form factor are used to obtain values of the magnitude of the Cabibbo-Kobayashi-Maskawa matrix element V_ub between 3.61 and 4.07 x 10^-3.

Assessment of Alaska reindeer populations and range conditions

Directory of Open Access Journals (Sweden)

J. D. Swanson

1992-10-01

Full Text Available Populations of reindeer (Rangifer tarandus have fluctated greatly since their introduction to Alaska in 1891. In the 1930s, reported numbers exceeded 600 000. Presently, 38 000 reindeer graze 6.2 million ha of rangeland and woodland in Western Alaska (from 66°54'N to 52°07'N latitude. Condition of winter range producing fruticose lichens (Cladina rangiferina, Cladina arbuscula, Cladina stellaris, Cetraria cucullata, Cetraria islandica is of major concern. Monitoring programs have been established for vegetation, fire, reindeer and wildlife. Reindeer have overgrazed lichen resources on some Bering Sea Islands. Wildfires have had the greatest impact on lichen range depletion on the mainland. Overgrazing has been a problem in localized areas. Moose (Alces alces and muskox (Ovibos moschatus rarely contribute to major lichen depletion. 60-80% of the mainland and 5-30% of most island winter lichen ranges are presently estimated to be in good to excellent ecological condition. Procedures for assessing condition of the lichen ranges are being further refined.

Intermediate-range chemical ordering of cations in molten RbCl-AgCl

Energy Technology Data Exchange (ETDEWEB)

Tahara, S. [Department of Physics and Earth Sciences, Faculty of Science, University of the Ryukyus, Okinawa 903-0213 (Japan); Research and Utilization Division, Japan Synchrotron Radiation Research Institute (JASRI, SPring-8), Hyogo 679-5198 (Japan); Kawakita, Y. [J-PARC Center, Japan Atomic Energy Agency (JAEA), Ibaraki 319-1195 (Japan); Shimakura, H. [Faculty of Pharmacy, Niigata University of Pharmacy and Applied Life Sciences, Niigata 956-8603 (Japan); Ohara, K. [Research and Utilization Division, Japan Synchrotron Radiation Research Institute (JASRI, SPring-8), Hyogo 679-5198 (Japan); Fukami, T. [Department of Physics and Earth Sciences, Faculty of Science, University of the Ryukyus, Okinawa 903-0213 (Japan); Takeda, S. [Department of Physics, Faculty of Sciences, Kyushu University, Fukuoka 812-8581 (Japan)

2015-07-28

A first sharp diffraction peak (FSDP) is observed in the X-ray total structure factor of a molten mixture of RbCl-AgCl, while both pure melts of RbCl and AgCl do not exhibit FSDP individually. Molecular dynamics simulations were performed to investigate the origin of the FSDP with the polarizable ion model (PIM). Coexistence of covalent Ag–Cl and ionic Rb–Cl bonds leads the system to evolve intermediate range ordering, which is simulated by introducing the induced polarization in different ways between Ag–Cl with fully polarizable treatment based on Vashishta-Raman potential and Rb–Cl with suppression over-polarization in the nearest neighbor contribution based on Born-Meyer potential. The partial structure factors for both the Ag–Ag and Rb–Rb correlations, S{sub AgAg}(Q) and S{sub RbRb}(Q), show a positive contribution to the FSDP, while S{sub AgRb}(Q) for the Ag–Rb correlation exhibits a negative contribution, indicating that Ag and Rb ions are distributed in an alternating manner within the intermediate-range length scale. The origin of the intermediate-range chemical ordering of cations can be ascribed to the preferred direction of the dipole moments of anions in the PIM.

Intermediate-range chemical ordering of cations in molten RbCl-AgCl

International Nuclear Information System (INIS)

Tahara, S.; Kawakita, Y.; Shimakura, H.; Ohara, K.; Fukami, T.; Takeda, S.

2015-01-01

A first sharp diffraction peak (FSDP) is observed in the X-ray total structure factor of a molten mixture of RbCl-AgCl, while both pure melts of RbCl and AgCl do not exhibit FSDP individually. Molecular dynamics simulations were performed to investigate the origin of the FSDP with the polarizable ion model (PIM). Coexistence of covalent Ag–Cl and ionic Rb–Cl bonds leads the system to evolve intermediate range ordering, which is simulated by introducing the induced polarization in different ways between Ag–Cl with fully polarizable treatment based on Vashishta-Raman potential and Rb–Cl with suppression over-polarization in the nearest neighbor contribution based on Born-Meyer potential. The partial structure factors for both the Ag–Ag and Rb–Rb correlations, S AgAg (Q) and S RbRb (Q), show a positive contribution to the FSDP, while S AgRb (Q) for the Ag–Rb correlation exhibits a negative contribution, indicating that Ag and Rb ions are distributed in an alternating manner within the intermediate-range length scale. The origin of the intermediate-range chemical ordering of cations can be ascribed to the preferred direction of the dipole moments of anions in the PIM

Fluctuation microscopy: a probe of medium range order

International Nuclear Information System (INIS)

Treacy, M M J; Gibson, J M; Fan, L; Paterson, D J; McNulty, I

2005-01-01

Fluctuation microscopy is a hybrid diffraction-imaging technique that detects medium range order in amorphous materials by examining spatial fluctuations in coherent scattering. These fluctuations appear as speckle in images and diffraction patterns. The volume of material contributing to the speckle is determined by the point-spread function (the resolution) of the imaging optics and the sample thickness. The spatial periodicities being probed are related to the diffraction vector. Statistical analysis of the speckle allows the random and non-random (ordered) contributions to be discriminated. The image resolution that gives the maximum speckle contrast, as determined by the normalized variance of the image intensity, is determined by the characteristic length scale of the ordering. Because medium range ordering length scales can extend out to about the tenth coordination shell, fluctuation microscopy tends to be a low image resolution technique. This review presents the kinematical scattering theory underpinning fluctuation microscopy and a description of fluctuation electron microscopy as it has been employed in the transmission electron microscope for studying amorphous materials. Recent results using soft x-rays for studying nanoscale materials are also presented. We summarize outstanding issues and point to possible future directions for fluctuation microscopy as a technique

Contributions to the study of fast neutron spectrum in the 10 keV - 3 MeV range

International Nuclear Information System (INIS)

Garlea, I.

1979-01-01

The main objective of the work presented in this thesis was to create a fast neutron spectrum corresponding to the conditions required for a reference neutron field. The reference system for the fast neutron dosimetry in reactors, which the author promoted, is referred to as ΣΣ-ITN in the books. The conditions for introducing the ΣΣ systems into the thermal columns have been determined. The original contribution consists in determining the Westcott parameters of reactions 151 Eu(n,γ) 152 Eu and 176 Lu(n,γ) 17 +H7Lu used as thermal spectrum factors. The neutron description of the spectrum in cavity ΣΣ revealed that it is a Maxwell thermal spectrum displaying a temperature of 305+-7 deg C and a very small epithermal component (phisub(epi)/phisub(thermal) =4,5.10 -4 ). Better methods for determining reaction absolute rates resulted in less errors in calculating the microscopic integral sections mediated on the ΣΣ spectrum; there are under 5% errors for the fission cross sections and between 3% and 8% errors for the activating ones. The section values determined by the author have been included into the EXFOR library (IAEA); they are considered as reference measuremtns for the nuclear data improvement program. Testing the proposed method for the TRIGA on the ΣΣ-INT system proved that the multiple foil method provides correct results for both describing the spectral shape and for obtaining absolute values of the flux. Taking into account that the ΣΣ-ITN spectrum is a rapid one, the proposed method could not be tested within the low energy thermal and epithermal domain. For testing the method on an operational reactor, the core of the VVR-S IFIN reactor was employed. Due to the spectral structure of this reactor, it was possible to test the procedure within the whole energy range. In this view, the 5/10 core channel was selected which is similar to the channel required for measurements in the TRIGA-ROMANIA reactor. The absolute spectrum values are given in

Enhancing of optic phonon contribution in hydrodynamic phonon transport

Science.gov (United States)

de Tomas, C.; Cantarero, A.; Lopeandia, A. F.; Alvarez, F. X.

2015-10-01

In the framework of the kinetic-collective model of phonon heat transport, we analyze how each range of the phonon frequency spectrum contributes to the total thermal conductivity both in the macro and the nanoscale. For this purpose, we use two case study samples: naturally occurring bulk silicon and a 115 nm of diameter silicon nanowire. We show that the contribution of high-energy phonons (optic branches) is non-negligible only when N-collisions are strongly present. This contribution increases when the effective size of the sample decreases, and it is found to be up to a 10% at room temperature for the 115 nm nanowire, corroborating preliminar ab-initio predictions.

Nuclear theory research. Technical progress report

International Nuclear Information System (INIS)

1982-01-01

Progress is briefly described on the following studies: (1) Dirac phenomenology for deuteron elastic scattering, (2) Dirac wave functions in nuclear distorted wave calculations, (3) impulse approximation for p→p → dπ + reaction above the 3-3 resonance, (4) coherent π production, (5) nuclear potentials from Dirac bound state wavefunctions, (6) nonlocality effects in nuclear reactions, (7) unhappiness factors in DWBA description of (t,p) and (p,t) reactions, (8) absolute normalization of three-nucleon transfer reactions, (9) formulation of a finite-range CCBA computer program, (10) crossing symmetric solutions of the low equations, (11) pion scattering from quark bags, (12) study of the p 11 channel in the delta model, (13) isovector corrections in pion-nucleus scattering, (14) pionic excitation of nuclear giant resonances, and (15) isospin dependence of the second-order pion-nucleus optical potential

Model Based Verification of Cyber Range Event Environments

Science.gov (United States)

2015-11-13

that may include users, applications, operating systems, servers, hosts, routers, switches, control planes , and instrumentation planes , many of...which lack models for their configuration. Our main contributions in this paper are the following. First, we have developed a configuration ontology...configuration errors in environment designs for several cyber range events. The rest of the paper is organized as follows. Section 2 provides an overview of

Determination of the pion-nucleon coupling constant and scattering lengths

International Nuclear Information System (INIS)

Ericson, T.E.O.; Loiseau, B.; Thomas, A.W.

2002-01-01

We critically evaluate the isovector Goldberger-Miyazawa-Oehme (GMO) sum rule for forward πN scattering using the recent precision measurements of π - p and π - d scattering lengths from pionic atoms. We deduce the charged-pion-nucleon coupling constant, with careful attention to systematic and statistical uncertainties. This determination gives, directly from data, g c 2 (GMO)/4π=14.11±0.05(statistical)±0.19(systematic) or f c 2 /4π=0.0783(11). This value is intermediate between that of indirect methods and the direct determination from backward np differential scattering cross sections. We also use the pionic atom data to deduce the coherent symmetric and antisymmetric sums of the pion-proton and pion-neutron scattering lengths with high precision, namely, (a π - p +a π - n )/2=[-12±2(statistical)±8(systematic)]x10 -4 m π -1 and (a π - p -a π - n )/2=[895±3(statistical)±13 (systematic)]x10 -4 m π -1 . For the need of the present analysis, we improve the theoretical description of the pion-deuteron scattering length

QCD at finite isospin chemical potential

Science.gov (United States)

Brandt, Bastian B.; Endrődi, Gergely; Schmalzbauer, Sebastian

2018-03-01

We investigate the properties of QCD at finite isospin chemical potential at zero and non-zero temperatures. This theory is not affected by the sign problem and can be simulated using Monte-Carlo techniques. With increasing isospin chemical potential and temperatures below the deconfinement transition the system changes into a phase where charged pions condense, accompanied by an accumulation of low modes of the Dirac operator. The simulations are enabled by the introduction of a pionic source into the action, acting as an infrared regulator for the theory, and physical results are obtained by removing the regulator via an extrapolation. We present an update of our study concerning the associated phase diagram using 2+1 flavours of staggered fermions with physical quark masses and the comparison to Taylor expansion. We also present first results for our determination of the equation of state at finite isospin chemical potential and give an example for a cosmological application. The results can also be used to gain information about QCD at small baryon chemical potentials using reweighting with respect to the pionic source parameter and the chemical potential and we present first steps in this direction.

The Contribution of Marital Happiness to Global Happiness.

Science.gov (United States)

Glenn, Norval D.; Weaver, Charles N.

1981-01-01

Data from six U.S. national surveys compared the estimated contributions to global happiness and marital happiness and satisfaction with each of seven aspects of life, ranging from work to friendships. Findings indicated that Americans depend very heavily on their marriages for their psychological well-being. (Author)

Diffusion of ionic and non-ionic contrast agents in articular cartilage with increased cross-linking--contribution of steric and electrostatic effects.

Science.gov (United States)

Kulmala, K A M; Karjalainen, H M; Kokkonen, H T; Tiitu, V; Kovanen, V; Lammi, M J; Jurvelin, J S; Korhonen, R K; Töyräs, J

2013-10-01

To investigate the effect of threose-induced collagen cross-linking on diffusion of ionic and non-ionic contrast agents in articular cartilage. Osteochondral plugs (Ø=6mm) were prepared from bovine patellae and divided into two groups according to the contrast agent to be used in contrast enhanced computed tomography (CECT) imaging: (I) anionic ioxaglate and (II) non-ionic iodixanol. The groups I and II contained 7 and 6 sample pairs, respectively. One of the paired samples served as a reference while the other was treated with threose to induce collagen cross-linking. The equilibrium partitioning of the contrast agents was imaged after 24h of immersion. Fixed charge density (FCD), water content, contents of proteoglycans, total collagen, hydroxylysyl pyridinoline (HP), lysyl pyridinoline (LP) and pentosidine (Pent) cross-links were determined as a reference. The equilibrium partitioning of ioxaglate (group I) was significantly (p=0.018) lower (-23.4%) in threose-treated than control samples while the equilibrium partitioning of iodixanol (group II) was unaffected by the threose-treatment. FCD in the middle and deep zones of the cartilage (pionic iodixanol showed no changes in partition after cross-linking, in contrast to anionic ioxaglate, we conclude that the cross-linking induced changes in charge distribution have greater effect on diffusion compared to the cross-linking induced changes in steric hindrance. Copyright © 2013 IPEM. Published by Elsevier Ltd. All rights reserved.

Understanding synthesis imaging dynamic range

Science.gov (United States)

Braun, R.

2013-03-01

We develop a general framework for quantifying the many different contributions to the noise budget of an image made with an array of dishes or aperture array stations. Each noise contribution to the visibility data is associated with a relevant correlation timescale and frequency bandwidth so that the net impact on a complete observation can be assessed when a particular effect is not captured in the instrumental calibration. All quantities are parameterised as function of observing frequency and the visibility baseline length. We apply the resulting noise budget analysis to a wide range of existing and planned telescope systems that will operate between about 100 MHz and 5 GHz to ascertain the magnitude of the calibration challenges that they must overcome to achieve thermal noise limited performance. We conclude that calibration challenges are increased in several respects by small dimensions of the dishes or aperture array stations. It will be more challenging to achieve thermal noise limited performance using 15 m class dishes rather than the 25 m dishes of current arrays. Some of the performance risks are mitigated by the deployment of phased array feeds and more with the choice of an (alt,az,pol) mount, although a larger dish diameter offers the best prospects for risk mitigation. Many improvements to imaging performance can be anticipated at the expense of greater complexity in calibration algorithms. However, a fundamental limitation is ultimately imposed by an insufficient number of data constraints relative to calibration variables. The upcoming aperture array systems will be operating in a regime that has never previously been addressed, where a wide range of effects are expected to exceed the thermal noise by two to three orders of magnitude. Achieving routine thermal noise limited imaging performance with these systems presents an extreme challenge. The magnitude of that challenge is inversely related to the aperture array station diameter.

Quantitative tests of pion physics in simple nuclear systems

International Nuclear Information System (INIS)

Ericson, T.E.O.

1984-01-01

The need for quantitative tests of pion physics in simple nuclear systems is discussed under eight topic headings. These include: one-pion exchange potential, p-wave NN scattering lengths, opep pole in forward NN dispersion relations, np → pn near the forward direction, pionic interactions, deuteron D/S ratio eta, deuteron quadrupole moment, and finally the joint case of eta and Q. (U.K.)

8. Biennial session on nuclear physics

International Nuclear Information System (INIS)

1985-01-01

In this biennial, some importance have been accorded deliberately to heavy ion experiment planning at very high energy and on results than can be waited for. Besides these collisions, different subjects are dealt with such as kaon scattering, hot nuclei, electron channeling photon and pion reactions in light nuclei, new forms of radioactivity, exotic nuclei, theoretical processing of nuclear dynamics, bag models, and pionic atoms [fr

An improved optical potential for low-energy pion-nucleus scattering

International Nuclear Information System (INIS)

Khankhasaev, M.Kh.; Topil'skaya, N.S.

1988-01-01

A new procedure for calculating the imaginary part the of Stricker, McManus and Carr (SMC) optical potential is proposed. It is based on an approximate expression for the pion-nucleon scattering amplitude including nuclear structure effects. It is shown that the resulting potential with the absorption parameters fitted to the pionic atom data provides a good description of the scattering up to 50 MeV

The ρ and ω mesons production in the γp reaction

International Nuclear Information System (INIS)

Das, Swapan

2016-01-01

The ρ - ω interference has been well studied in the pion decay channel. The information about this interference in the e"+ e"- decay exist only for the γ-C reaction due to Biggs et al., and for the γ-Be reaction due to Alvenslaben et al.. The interference phases derived in the pionic and electromagnetic decay channels are different and this discrepancy is never understood

The Contribution of Matched Envelope Dynamic Range to the Binaural Benefits in Simulated Bilateral Electric Hearing

Science.gov (United States)

Chen, Fei; Wong, Lena L. N.; Qiu, Jianxin; Liu, Yehai; Azimi, Behnam; Hu, Yi

2013-01-01

Purpose: This study examined the effects of envelope dynamic-range mismatch on the intelligibility of Mandarin speech in noise by simulated bilateral electric hearing. Method: Noise-vocoded Mandarin speech, corrupted by speech-shaped noise at 5 and 0 dB signal-to-noise ratios, was presented unilaterally or bilaterally to 10 normal-hearing…

Chiral symmetry effect on the pion-nucleon coupling constant; O efeito da simetria quiral na constante de acoplamento pion-nucleon

Energy Technology Data Exchange (ETDEWEB)

Araujo, Vanilse da Silva

1997-12-31

In this work we study the effects of chiral symmetry in the pion-nucleon coupling constant in the context of the linear {sigma}- model. First, we introduce the linear {sigma}-model and we discuss the phenomenological hypothesis of CVC and PCAC. Next, we calculate the coupling constant g+{pi}{sub NN}(q{sup 2}) and the nucleon pionic mean square radius considering the contribution of all the diagrams up to one-loop in the framework of the linear {sigma}-model for different values of the mass of the sigma meson and we compare them with the phenomenological form factors. Finally we make an extension of the linear {sigma}-model that consists of taking into account the mass differences of ions and nucleons into the Lagrangian of the model, to study the change dependence of g{sub {pi}nn} (q{sup 2}) and of the mean square radius. (author) 21 refs., 17 figs., 4 tabs.

A Palaeoenvironmental contribution to the study of trashumance in the Gredos Mountain Range (Ávila

Directory of Open Access Journals (Sweden)

José Antonio López Sáez

2009-04-01

Full Text Available The Avilan sector of the Gredos Mountain Range represents one of the Iberian Peninsula’s most valuable cultural landscapes. From Prehistory to the present, the importance of trashumance in this region has played a key role in shaping its ecosystyems. Using pollen analysis to examine historical transformations in the region’s ecology, both those engendered by human activity and those relating to palaeoclimatic dynamics, this paper examines the diachronic evolution of the vegetation of the Serranillos Mountain Pass during the Late Holocene.

Neocortical inhibitory activities and long-range afferents contribute to the synchronous onset of silent states of the neocortical slow oscillation.

Science.gov (United States)

Lemieux, Maxime; Chauvette, Sylvain; Timofeev, Igor

2015-02-01

During slow-wave sleep, neurons of the thalamocortical network are engaged in a slow oscillation (<1 Hz), which consists of an alternation between the active and the silent states. Several studies have provided insights on the transition from the silent, which are essentially periods of disfacilitation, to the active states. However, the conditions leading to the synchronous onset of the silent state remain elusive. We hypothesized that a synchronous input to local inhibitory neurons could contribute to the transition to the silent state in the cat suprasylvian gyrus during natural sleep and under ketamine-xylazine anesthesia. After partial and complete deafferentation of the cortex, we found that the silent state onset was more variable among remote sites. We found that the transition to the silent state was preceded by a reduction in excitatory postsynaptic potentials and firing probability in cortical neurons. We tested the impact of chloride-mediated inhibition in the silent-state onset. We uncovered a long-duration (100-300 ms) inhibitory barrage occurring about 250 ms before the silent state onset in 3-6% of neurons during anesthesia and in 12-15% of cases during natural sleep. These inhibitory activities caused a decrease in cortical firing that reduced the excitatory drive in the neocortical network. That chain reaction of disfacilitation ends up on the silent state. Electrical stimuli could trigger a network silent state with a maximal efficacy in deep cortical layers. We conclude that long-range afferents to the neocortex and chloride-mediated inhibition play a role in the initiation of the silent state. Copyright © 2015 the American Physiological Society.

Off-shell pairing correlations from meson-exchange theory of nuclear forces

International Nuclear Information System (INIS)

Sedrakian, Armen

2003-01-01

We develop a model of off-mass-shell pairing correlations in nuclear systems, which is based on the meson-exchange picture of nuclear interactions. The temporal retardations in the model are generated by the Fock-exchange diagrams. The kernel of the complex gap equation for baryons is related to the in-medium spectral function of mesons, which is evaluated nonperturbatively in the random phase approximation. The model is applied to the low-density neutron matter in neutron star crusts by separating the interaction into a long-range one-pion-exchange component and a short-range component parametrized in terms of Landau Fermi liquid parameters. The resulting Eliashberg-type coupled nonlinear integral equations are solved by an iterative procedure. We find that the self-energies extend to off-shell energies of the order of several tens of MeV. At low energies the damping of the neutron pair correlations due to the coupling to the pionic modes is small, but becomes increasingly important as the energy is increased. We discuss an improved quasiclassical approximation under which the numerical solutions are obtained

Slow electron contribution to inelastic reflection anisotropy

International Nuclear Information System (INIS)

Podsvirov, O.A.; Kuznetsov, Yu.A.

1980-01-01

Investigated is electron contribution with low energy (up to 1 keV) to the anisotropy of electron inelastic reflection (IRE) from silicon monocrystal (111) within 12-50 keV energy range of primary electrons. Experimental data on IRE anisotropy are presented: delay curves for silicon monocrystal, permitting to separate electrons with the energy up to 1 keV, dependences of IRE anisotropy on the energy of primary electrons for the systems - monocrystalline silicon-amorphous silicon film and delay curves for such systems (film thickness varies from 20 to 2000 A). Suggested is a phenomenologic model, permitting to take into account the contribution of slow electrons to IRE anisotropy: it is supposed, that three groups of electrons take part in the formation of the latter: elastic and inelastic reflected electrons, slow electrons, excited by primary electrons and slow electrons, generated by the reverse flow of the scattered electrons. Contribution of electrons, different by origin, to IRE anisotropy is evaluated in accordance with the experimental data on the basis of this model. It is stated, that slow electrons constitute approximately one half of the IRE anisotropy value, the contribution of both groups of slow electrons being approximately equal

Development and Analysis of Group Contribution Plus Models for Property Prediction of Organic Chemical Systems

DEFF Research Database (Denmark)

Mustaffa, Azizul Azri

for the GIPs are then used in the UNIFAC model to calculate activity coefficients. This approach can increase the application range of any “host” UNIFAC model by providing a reliable predictive model towards fast and efficient product development. This PhD project is focused on the analysis and further......Prediction of properties is important in chemical process-product design. Reliable property models are needed for increasingly complex and wider range of chemicals. Group-contribution methods provide useful tool but there is a need to validate them and improve their accuracy when complex chemicals...... are present in the mixtures. In accordance with that, a combined group-contribution and atom connectivity approach that is able to extend the application range of property models has been developed for mixture properties. This so-called Group-ContributionPlus (GCPlus) approach is a hybrid model which combines...

Biomass burning contributions to urban aerosols in a coastal Mediterranean city.

Science.gov (United States)

Reche, C; Viana, M; Amato, F; Alastuey, A; Moreno, T; Hillamo, R; Teinilä, K; Saarnio, K; Seco, R; Peñuelas, J; Mohr, C; Prévôt, A S H; Querol, X

2012-06-15

Mean annual biomass burning contributions to the bulk particulate matter (PM(X)) load were quantified in a southern-European urban environment (Barcelona, Spain) with special attention to typical Mediterranean winter and summer conditions. In spite of the complexity of the local air pollution cocktail and the expected low contribution of biomass burning emissions to PM levels in Southern Europe, the impact of these emissions was detected at an urban background site by means of tracers such as levoglucosan, K(+) and organic carbon (OC). The significant correlation between levoglucosan and OC (r(2)=0.77) and K(+) (r(2)=0.65), as well as a marked day/night variability of the levoglucosan levels and levoglucosan/OC ratios was indicative of the contribution from regional scale biomass burning emissions during night-time transported by land breezes. In addition, on specific days (21-22 March), the contribution from long-range transported biomass burning aerosols was detected. Quantification of the contribution of biomass burning aerosols to PM levels on an annual basis was possible by means of the Multilinear Engine (ME). Biomass burning emissions accounted for 3% of PM(10) and PM(2.5) (annual mean), while this percentage increased up to 5% of PM(1). During the winter period, regional-scale biomass burning emissions (agricultural waste burning) were estimated to contribute with 7±4% of PM(2.5) aerosols during night-time (period when emissions were clearly detected). Long-range transported biomass burning aerosols (possibly from forest fires and/or agricultural waste burning) accounted for 5±2% of PM(2.5) during specific episodes. Annually, biomass burning emissions accounted for 19%-21% of OC levels in PM(10), PM(2.5) and PM(1). The contribution of this source to K(+) ranged between 48% for PM(10) and 97% for PM(1) (annual mean). Results for K(+) from biomass burning evidenced that this tracer is mostly emitted in the fine fraction, and thus coarse K(+) could not be

Contributing to Functionality

DEFF Research Database (Denmark)

Törpel, Bettina

2006-01-01

The objective of this paper is the design of computer supported joint action spaces. It is argued against a view of functionality as residing in computer applications. In such a view the creation of functionality is equivalent to the creation of computer applications. Functionality, in the view...... advocated in this paper, emerges in the specific dynamic interplay of actors, objectives, structures, practices and means. In this view, functionality is the result of creating, harnessing and inhabiting computer supported joint action spaces. The successful creation and further development of a computer...... supported joint action space comprises a whole range of appropriate design contributions. The approach is illustrated by the example of the creation of the computer supported joint action space "exchange network of voluntary union educators". As part of the effort a group of participants created...

Multi-GNSS signal-in-space range error assessment - Methodology and results

Science.gov (United States)

Montenbruck, Oliver; Steigenberger, Peter; Hauschild, André

2018-06-01

The positioning accuracy of global and regional navigation satellite systems (GNSS/RNSS) depends on a variety of influence factors. For constellation-specific performance analyses it has become common practice to separate a geometry-related quality factor (the dilution of precision, DOP) from the measurement and modeling errors of the individual ranging measurements (known as user equivalent range error, UERE). The latter is further divided into user equipment errors and contributions related to the space and control segment. The present study reviews the fundamental concepts and underlying assumptions of signal-in-space range error (SISRE) analyses and presents a harmonized framework for multi-GNSS performance monitoring based on the comparison of broadcast and precise ephemerides. The implications of inconsistent geometric reference points, non-common time systems, and signal-specific range biases are analyzed, and strategies for coping with these issues in the definition and computation of SIS range errors are developed. The presented concepts are, furthermore, applied to current navigation satellite systems, and representative results are presented along with a discussion of constellation-specific problems in their determination. Based on data for the January to December 2017 time frame, representative global average root-mean-square (RMS) SISRE values of 0.2 m, 0.6 m, 1 m, and 2 m are obtained for Galileo, GPS, BeiDou-2, and GLONASS, respectively. Roughly two times larger values apply for the corresponding 95th-percentile values. Overall, the study contributes to a better understanding and harmonization of multi-GNSS SISRE analyses and their use as key performance indicators for the various constellations.

How Precisely can we Determine the $\\piNN$ Coupling Constant from the Isovector GMO Sum Rule?

CERN Document Server

Loiseau, B; Thomas, A W

1999-01-01

The isovector GMO sum rule for zero energy forward pion-nucleon scattering iscritically studied to obtain the charged pion-nucleon coupling constant usingthe precise negatively charged pion-proton and pion-deuteron scattering lengthsdeduced recently from pionic atom experiments. This direct determination leadsto a pseudoscalar charged pion-nucleon coupling constant of 14.23 +- 0.09(statistic) +- 0.17 (systematic). We obtain also accurate values for thepion-nucleon scattering lengths.

Magnetic moments of multiquark systems and restraints upon the six-quark admixture to the deuteron wave functions

International Nuclear Information System (INIS)

Kondratyuk, L.A.; Krivoruchenko, M.I.; Shchepkin, M.G.

1986-01-01

The magnetic moment of the six-quark bag with the deuteron quantum numbers is calculated in the chiral bag model taking into account the gluonic and the pionic corrections. For the six-quark bag radius R 6q =1.18-1.38 fm (corresponding to the nucleon bag radius R 3q =0.8-1.0 fm) the magnetic moment equals m D 6q =1.17-1.23 nuclear magnetons. This result together with the deuteron magnetic momentum data provides a restraint upon the six-quark bag admixture in the deuteron P B < or approx. 3%. This value is a few times lower than the probability that two nucleons are in the range r < 1.4 fm. Therefore, it may be interpreted as an evidence for a considerable difference between the properties of the effective bag in the deuteron and of the MIT bag

How the nursing profession can contribute to sustainable development goals.

Science.gov (United States)

Benton, David; Shaffer, Franklin

2016-11-01

As of 1 January 2016, the UN sustainable development goals (SDGs) became the focus of global efforts on a wide range of development agenda. The SDGs have subsumed the work of the UN millennium development goals (MDGs), so it is timely to reflect on the contribution made by nurses and midwives, so that we can optimise the profession's contribution to the 17 SDGs. This article reports the results of a scientometrics analysis of the published literature related to the MDGs and SDGs indexed in CINAHL, which identified the underlying themes addressed by nurses and midwives. It shows how analysis demonstrates that although nursing was slow to engage with the MDG agenda, it has made some progress in contributing to SDG scholarship. So far this contribution has been narrowly focused, but the profession could contribute to all 17 of the SDG goals. Routine updates of the analysis described here could help monitor progress, identify gaps in nursing's contributions to the goals, and provide further impetus to its engagement in this major global policy initiative.

Viking lander tracking contributions to Mars mapping

International Nuclear Information System (INIS)

Michael, W.H. Jr.

1979-01-01

The major recent advances in planetary mapping have been accomplished through use of photography from orbiting satellites, as is the case for Mars with Mariner and Viking photographs. The requirement for greater precision demands that inputs to the photogrammatic process be more precisely defined. This paper describes how analyses of Doppler and ranging data from the Viking landers are contributing to more precise mapping of Mars in several specific areas. (Auth.)

Probing odd-triplet contributions to the long-ranged proximity effect by scanning tunneling spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Diesch, Simon; Machon, Peter; Belzig, Wolfgang; Scheer, Elke [Universitaet Konstanz, Konstanz (Germany); Suergers, Christoph; Beckmann, Detlef [Karlsruhe Institute of Technology, Karlsruhe (Germany)

2015-07-01

In conventional superconductors, electrons are bound in singlet Cooper pairs, i.e. with opposite spin. More recently, experiments on superconductor-ferromagnet-systems have shown Cooper pairs tunneling through ferromagnetic layers, indicating Cooper pairs of equal spin, thus corresponding to a long-range triplet proximity effect. Most experimental evidence for triplet superconductivity comes from observations of the thickness dependence of the Josephson current through a ferromagnetic barrier, but there is an increasing interest in obtaining direct spectroscopic evidence. This project aims at analyzing the electronic density of states of a thin diffusive normal metal layer (Ag) coupled to a superconductor (Al) across a ferromagnetic insulator (EuS) using a scanning tunneling microscope in spectroscopy mode at 280 mK. For this purpose, we fabricated EuS films of different thicknesses and acquired spectroscopic data at different magnetic fields. We observe significant broadening of the superconductive energy gap and a variety of sub-gap structures including zero-bias conductance peaks induced by the presence of the ferromagnet.

Broad-scale latitudinal variation in female reproductive success contributes to the maintenance of a geographic range boundary in bagworms (Lepidoptera: Psychidae.

Directory of Open Access Journals (Sweden)

Marc Rhainds

Full Text Available BACKGROUND: Geographic range limits and the factors structuring them are of great interest to biologists, in part because of concerns about how global change may shift range boundaries. However, scientists lack strong mechanistic understanding of the factors that set geographic range limits in empirical systems, especially in animals. METHODOLOGY/PRINCIPAL FINDINGS: Across dozens of populations spread over six degrees of latitude in the American Midwest, female mating success of the evergreen bagworm Thyridopteryx ephemeraeformis (Lepidoptera: Psychidae declines from ∼100% to ∼0% near the edge of the species range. When coupled with additional latitudinal declines in fecundity and in egg and pupal survivorship, a spatial gradient of bagworm reproductive success emerges. This gradient is associated with a progressive decline in local abundance and an increased risk of local population extinction, up to a latitudinal threshold where extremely low female fitness meshes spatially with the species' geographic range boundary. CONCLUSIONS/SIGNIFICANCE: The reduction in fitness of female bagworms near the geographic range limit, which concords with the abundant centre hypothesis from biogeography, provides a concrete, empirical example of how an Allee effect (increased pre-reproductive mortality of females in sparsely populated areas may interact with other demographic factors to induce a geographic range limit.

Contribution of limb momentum to power transfer in athletic wheelchair pushing.

Science.gov (United States)

Masson, G; Bégin, M-A; Lopez Poncelas, M; Pelletier, S-K; Lessard, J-L; Laroche, J; Berrigan, F; Langelier, E; Smeesters, C; Rancourt, D

2016-09-06

Pushing capacity is a key parameter in athletic racing wheelchair performance. This study estimated the potential contribution of upper limb momentum to pushing. The question is relevant since it may affect the training strategy adopted by an athlete. A muscle-free Lagrangian dynamic model of the upper limb segments was developed and theoretical predictions of power transfer to the wheelchair were computed during the push phase. Results show that limb momentum capacity for pushing can be in the order of 40J per push cycle at 10m/s, but it varies with the specific pushing range chosen by the athlete. Although use of momentum could certainly help an athlete improve performance, quantifying the actual contribution of limb momentum to pushing is not trivial. A preliminary experimental investigation on an ergometer, along with a simplified model of the upper limb, suggests that momentum is not the sole contributor to power transfer to a wheelchair. Muscles substantially contribute to pushing, even at high speeds. Moreover, an optimal pushing range is challenging to find since it most likely differs if an athlete chooses a limb momentum pushing strategy versus a muscular exertion pushing strategy, or both at the same time. The study emphasizes the importance of controlling pushing range, although one should optimize it while also taking the dynamics of the recovery period into account. Copyright © 2016 Elsevier Ltd. All rights reserved.

Study of the dislocation contribution to the internal friction background of gold

Science.gov (United States)

Baur, J.; Benoit, W.

1987-04-01

The dislocation contribution to the internal friction (IF) background is studied in annealed gold samples containing various dilute concentrations of platinum impurities. The measurements are performed in the kHz frequency range in order to determine the loss mechanism responsible for the high IF background observed at these low frequencies. To this end, the IF background was systematically measured as a function of frequency, vibration amplitude, temperature, and impurity concentration. The experimental results show that the high dislocation contribution observed in annealed samples is strain-amplitude independent for amplitudes in the range 10-7 to 2×10-6, but rapidly decreases for amplitudes smaller than 10-7. In particular, the dislocation contribution tends to zero when the strain amplitude tends to zero. Furthermore, this contribution is frequency independent. These observations demonstrate that the dislocation contribution cannot be explained by relaxations. In particular, this contribution cannot be attributed to a viscous damping of the dislocation motion. On the contrary, the experiments show that the IF background due to dislocations must be explained by hysteretic and athermal motions of dislocations interacting with point defects. However, these hysteretic motions are not due to breakaway of dislocations from pinning points distributed along their length. The experimental results can be explained by the presence of point defects close to the dislocations, but not on them. The mechanical energy loss is attributed to hysteretic motions of dislocations between potential minima created by point defects.

Ranging behavior relates to welfare indicators pre- and post-range access in commercial free-range broilers.

Science.gov (United States)

Taylor, Peta S; Hemsworth, Paul H; Groves, Peter J; Gebhardt-Henrich, Sabine G; Rault, Jean-Loup

2018-06-01

Little is known about the effect of accessing an outdoor range on chicken welfare. We tracked individual ranging behavior of 538 mixed-sex Ross 308 chickens on a commercial farm across 4 flocks in winter and summer. Before range access, at 17 to 19 d of age, and post-range access, at 30 to 33 and 42 to 46 d of age in winter and summer flocks respectively, welfare indicators were measured on chickens (pre-range: winter N = 292; summer N = 280; post-range: winter N = 131; summer N = 140), including weight, gait score, dermatitis and plumage condition. Post-ranging autopsies were performed (winter: N = 170; summer: N = 60) to assess breast burn, leg health, and ascites. Fewer chickens accessed the range in winter flocks (32.5%) than summer flocks (82.1%). Few relationships between welfare and ranging were identified in winter, likely due to minimal ranging and the earlier age of post-ranging data collection compared to summer flocks. In summer flocks prior to range access, chickens that accessed the range weighed 4.9% less (P = 0.03) than chickens that did not access the range. Pre-ranging weight, gait score, and overall plumage cover predicted the amount of range use by ranging chickens in summer flocks (P ranging behavior. In summer flocks post-range access, ranging chickens weighed 12.8% less than non-ranging chickens (P range visits were associated with lower weight (P range was associated with lower weight (P range in summer is partly related to changes in broiler chicken welfare. Further investigations are required to determine causation.

Supersymmetric contribution to the electroweak ρ parameter

International Nuclear Information System (INIS)

Drees, M.; Hagiwara, K.

1990-01-01

Contributions to the electroweak ρ parameter, the ratio of the neutral- and charged-current strengths at zero-momentum transfer, are studied in the minimal extension of the standard model (SM) with softly broken supersymmetry. The effects of the extended Higgs sector, the gaugino-Higgsino sector, the light-squark--slepton sector and that of the stop-sbottom sector are studied separately, and the role of the custodial SU(2) V symmetry in each sector is clarified. The stop-sbottom sector is found to give potentially a most significant contribution to δρ which can double the standard-model contribution from the top-bottom sector, whereas all the remaining sectors contribute to δρ at the level of at most a few x10 -3 . In the supergravity model with radiative electroweak gauge symmetry breaking there are no extra sources of the SU(2) V breaking at the grand unification scale other than those present already in the SM, and the resulting δρ is found to be significantly smaller than in the general case. Constraints on the allowed range of δρ in the supergravity models are given by taking account of existing and prospective experimental mass limits of additional particles at CERN LEP and Sp bar pS and Fermilab Tevatron

A Monte Carlo calculation of the pionium break-up probability with different sets of pionium target cross sections

International Nuclear Information System (INIS)

Santamarina, C; Schumann, M; Afanasyev, L G; Heim, T

2003-01-01

Chiral perturbation theory predicts the lifetime of pionium, a hydrogen-like π + π - atom, to better than 3% precision. The goal of the DIRAC experiment at CERN is to obtain and check this value experimentally by measuring the break-up probability of pionium in a target. In order to accurately measure the lifetime one needs to know the relationship between the break-up probability and the lifetime to 1% accuracy. We have obtained this dependence by modelling the evolution of pionic atoms in the target using Monte Carlo methods. The model relies on the computation of the pionium-target-atom interaction cross sections. Three different sets of pionium-target cross sections with varying degrees of complexity were used: from the simplest first-order Born approximation involving only the electrostatic interaction to a more advanced approach, taking into account multiphoton exchanges and relativistic effects. We conclude that, in order to obtain the pionium lifetime to 1% accuracy from the break-up probability, the pionium-target cross sections must be known with the same accuracy for the low excited bound states of the pionic atom. This result has been achieved, for low Z targets, with the two most precise cross section sets. For large Z targets only the set accounting for multiphoton exchange satisfies the condition

Quantitative Evaluation of Range Degradation According to the Gradient of the Compensator in Passive Scattering Proton Therapy

Energy Technology Data Exchange (ETDEWEB)

Shin, Wook Geun; Min, Chul Hee [Radiation Convergence Engineering, Yonsei University, Seoul (Korea, Republic of); Kim, Chan Kyu; Kim, Hak Soo; Jeong, Jong Hwi; Lee, Se Byeong [Proton Therapy Center, National Center Center, Seoul (Korea, Republic of)

2017-04-15

The Bragg peak enables proton therapy to deliver a high conformal target dose without exit dose. The passive scattering proton therapy employees patient-specific aperture and range compensator to shape the lateral and distal beam, and to deliver conformal dose to the target volume. The inaccurate dose calculation could cause underdose in the target volume and overdose in the normal tissues. The purpose of this study is to quantitatively evaluate the range degradation due to the slope of the range compensator using TOPAS Monte Carlo (MC) tool. The current study quantitatively evaluates the scattering effect due to the compensator slope with MC method. Our results show that not only patient geometry but also range compensator significantly contributes to the dose degradation. The current study quantitatively evaluates the scattering effect due to the compensator slope with MC method. Our results show that not only patient geometry but also range compensator significantly contributes to the dose degradation.

Tailored long range forces on polarizable particles by collective scattering of broadband radiation

International Nuclear Information System (INIS)

Holzmann, D; Ritsch, H

2016-01-01

Collective coherent light scattering by polarizable particles creates surprisingly strong, long range inter-particle forces originating from interference of the light scattered by different particles. While for monochromatic laser beams this interaction decays with the inverse distance, we show here that in general the effective interaction range and geometry can be controlled by the illumination bandwidth and geometry. As generic example we study the modifications inter-particle forces within a 1D chain of atoms trapped in the field of a confined optical nanofiber mode. For two particles we find short range attraction as well as optical binding at multiple distances. The range of stable distances shrinks with increasing light bandwidth and for a very large bandwidth field as e.g. blackbody radiation. We find a strongly attractive potential up to a critical distance beyond which the force gets repulsive. Including multiple scattering can even lead to the appearance of a stable configuration at a large distance. Such broadband scattering forces should be observable contributions in ultra-cold atom interferometers or atomic clocks setups. They could be studied in detail in 1D geometries with ultra-cold atoms trapped along or within an optical nanofiber. Broadband radiation force interactions might also contribute in astrophysical scenarios as illuminated cold dust clouds. (paper)

Evolutionary patterns of range size, abundance and species richness in Amazonian angiosperm trees

Directory of Open Access Journals (Sweden)

Kyle Dexter

2016-09-01

Full Text Available Amazonian tree species vary enormously in their total abundance and range size, while Amazonian tree genera vary greatly in species richness. The drivers of this variation are not well understood. Here, we construct a phylogenetic hypothesis that represents half of Amazonian tree genera in order to contribute to explaining the variation. We find several clear, broad-scale patterns. Firstly, there is significant phylogenetic signal for all three characteristics; closely related genera tend to have similar numbers of species and similar mean range size and abundance. Additionally, the species richness of genera shows a significant, negative relationship with the mean range size and abundance of their constituent species. Our results suggest that phylogenetically correlated intrinsic factors, namely traits of the genera themselves, shape among lineage variation in range size, abundance and species richness. We postulate that tree stature may be one particularly relevant trait. However, other traits may also be relevant, and our study reinforces the need for ambitious compilations of trait data for Amazonian trees. In the meantime, our study shows how large-scale phylogenies can help to elucidate, and contribute to explaining, macroecological and macroevolutionary patterns in hyperdiverse, yet poorly understood regions like the Amazon Basin.

From heavy ions to exotic atoms

OpenAIRE

Indelicato, Paul; Trassinelli, Martino

2005-01-01

We review a number of experiments and theoretical calculations on heavy ions and exotic atoms, which aim at providing informations on fundamental interactions. Among those are propositions of experiments for parity violation measurements in heavy ions and high-precision mesurements of He-like transition energies in highly charged ions. We also describe recent experiments on pionic atoms, that make use of highly-charged ion transitions to obtain accurate measurements of strong interaction shif...

Studies of nuclear structure in antinucleon charge-exchange reactions

International Nuclear Information System (INIS)

Auerbach, N.

1986-01-01

The antinucleon-nucleus charge exchange reaction is discussed an its use as a probe of isovector excitations in nuclei is described. Attention is drawn to the fact that the (anti p,anti n) reaction will predominantly excite ''pionic'' (i.e., longitudinal spin) modes in nuclei. Comparison between (anti p,anti n) and (n,p) reactions is made. Plans for (anti p,anti n) experiments in the near future are mentioned. 21 refs., 3 figs

Classical model with pionic degrees of freedom for the description of high energetic heavy ion collisions

International Nuclear Information System (INIS)

Kunz, J.

1982-01-01

In this thesis the classical model is extended in order to regard the inelastic processes important in the heavy ion collisions of the considered energy range. For this a classical pion field was coupled to the nucleons via the pseudo-scalar #betta# 5 -interactions. Nucleon and pion fields were treated in a completely relativistic way. The equations of motion were analytically studied for the one-nucleon system. From the statical solution the bare mass of the nucleon was determined, and its dependence on both parameters of this modell, the coupling constant and the cut-off momentum of the form factor, was considered. (orig./HSI) [de

Geographical ranges in macroecology: Processes, patterns and implications

DEFF Research Database (Denmark)

Borregaard, Michael Krabbe

, are distributed over the entire Earth. Species’ ranges are one of the basic units of the science of macroecology, which deals with patterns in the distribution of life on Earth. An example of such patterns is the large geographic variation in species richness between areas. These patterns are closely linked...... for this relationship. In going through the mechanisms, I distinguish between ‘structural’ causes, such as differences between the niches of species; and ‘dynamic’ causes, such as dispersal of individuals among populations. A central conclusion is that both of these types of mechanisms contribute to creating...... group includes a popularly written book chapter, where the causes and consequences of the spatial distribution of organisms are introduced more generally. The second group consists of several papers investigating the link between ranges and richness patterns. Variation in species richness is probably...

Ranging Behaviour of Commercial Free-Range Laying Hens.

Science.gov (United States)

Chielo, Leonard Ikenna; Pike, Tom; Cooper, Jonathan

2016-04-26

In this study, the range use and behaviour of laying hens in commercial free-range flocks was explored. Six flocks were each visited on four separate days and data collected from their outdoor area (divided into zones based on distance from shed and available resources). These were: apron (0-10 m from shed normally without cover or other enrichments); enriched belt (10-50 m from shed where resources such as manmade cover, saplings and dust baths were provided); and outer range (beyond 50 m from shed with no cover and mainly grass pasture). Data collection consisted of counting the number of hens in each zone and recording behaviour, feather condition and nearest neighbour distance (NND) of 20 birds per zone on each visit day. In addition, we used techniques derived from ecological surveys to establish four transects perpendicular to the shed, running through the apron, enriched belt and outer range. Number of hens in each 10 m × 10 m quadrat was recorded four times per day as was the temperature and relative humidity of the outer range. On average, 12.5% of hens were found outside. Of these, 5.4% were found in the apron; 4.3% in the enriched zone; and 2.8% were in the outer range. This pattern was supported by data from quadrats, where the density of hens sharply dropped with increasing distance from shed. Consequently, NND was greatest in the outer range, least in the apron and intermediate in the enriched belt. Hens sampled in outer range and enriched belts had better feather condition than those from the apron. Standing, ground pecking, walking and foraging were the most commonly recorded activities with standing and pecking most likely to occur in the apron, and walking and foraging more common in the outer range. Use of the outer range declined with lower temperatures and increasing relative humidity, though use of apron and enriched belt was not affected by variation in these measures. These data support previous findings that outer range areas tend to be

Contribution to the NSAC long-range plan entitled

International Nuclear Information System (INIS)

GRETINA Physics Working Group, the GRETINA Advisor

2006-01-01

This is a time of great opportunity in nuclear spectroscopy. The development of radioactive beam capabilities around the world is opening a new landscape for discovery, and the connections between nuclear structure studies and astrophysics, neutrino physics, and physics beyond the standard model are stronger than ever. New detector technologies are evolving which can meet the challenges of the new generation of experiments. Leading these is the technology of ''γ-ray tracking'' which can revolutionize γ-ray spectroscopy in a way that large arrays of γ detectors did a decade ago. During the last few years this technology has been shown feasible and GRETINA a 1π detector is under construction. However, the momentum in developing this technology to its full potential must continue towards GRETA, a full 4π calorimeter. GRETA will carry γ-ray spectroscopy into the next generation where it will be needed to fully exploit the science opportunities at radioactive beam facilities and increase the reach of stable beam facilities. In addition, γ-ray tracking technology will have important applications for science, medicine, and homeland security

Long-range interaction between dust grains in plasma

Directory of Open Access Journals (Sweden)

D.Yu. Mishagli

2014-03-01

Full Text Available The nature of long-range interactions between dust grains in plasma is discussed. The dust grain interaction potential within a cell model of dusty plasma is introduced. The attractive part of inter-grain potential is described by multipole interaction between two electro-neutral cells. This allowed us to draw an analogy with molecular liquids where attraction between molecules is determined by dispersion forces. Also main ideas of the fluctuation theory for electrostatic field in cell model are formulated, and the dominating contribution to attractive part of inter-grain potential is obtained.

Ranging Behaviour of Commercial Free-Range Laying Hens

Directory of Open Access Journals (Sweden)

Leonard Ikenna Chielo

2016-04-01

Full Text Available In this study, the range use and behaviour of laying hens in commercial free-range flocks was explored. Six flocks were each visited on four separate days and data collected from their outdoor area (divided into zones based on distance from shed and available resources. These were: apron (0–10 m from shed normally without cover or other enrichments; enriched belt (10–50 m from shed where resources such as manmade cover, saplings and dust baths were provided; and outer range (beyond 50 m from shed with no cover and mainly grass pasture. Data collection consisted of counting the number of hens in each zone and recording behaviour, feather condition and nearest neighbour distance (NND of 20 birds per zone on each visit day. In addition, we used techniques derived from ecological surveys to establish four transects perpendicular to the shed, running through the apron, enriched belt and outer range. Number of hens in each 10 m × 10 m quadrat was recorded four times per day as was the temperature and relative humidity of the outer range. On average, 12.5% of hens were found outside. Of these, 5.4% were found in the apron; 4.3% in the enriched zone; and 2.8% were in the outer range. This pattern was supported by data from quadrats, where the density of hens sharply dropped with increasing distance from shed. Consequently, NND was greatest in the outer range, least in the apron and intermediate in the enriched belt. Hens sampled in outer range and enriched belts had better feather condition than those from the apron. Standing, ground pecking, walking and foraging were the most commonly recorded activities with standing and pecking most likely to occur in the apron, and walking and foraging more common in the outer range. Use of the outer range declined with lower temperatures and increasing relative humidity, though use of apron and enriched belt was not affected by variation in these measures. These data support previous findings that outer range

Super-ranging. A new ranging strategy in European badgers.

Directory of Open Access Journals (Sweden)

Aoibheann Gaughran

Full Text Available We monitored the ranging of a wild European badger (Meles meles population over 7 years using GPS tracking collars. Badger range sizes varied seasonally and reached their maximum in June, July and August. We analysed the summer ranging behaviour, using 83 home range estimates from 48 individuals over 6974 collar-nights. We found that while most adult badgers (males and females remained within their own traditional social group boundaries, several male badgers (on average 22% regularly ranged beyond these traditional boundaries. These adult males frequently ranged throughout two (or more social group's traditional territories and had extremely large home ranges. We therefore refer to them as super-rangers. While ranging across traditional boundaries has been recorded over short periods of time for extraterritorial mating and foraging forays, or for pre-dispersal exploration, the animals in this study maintained their super-ranges from 2 to 36 months. This study represents the first time such long-term extra-territorial ranging has been described for European badgers. Holding a super-range may confer an advantage in access to breeding females, but could also affect local interaction networks. In Ireland & the UK, badgers act as a wildlife reservoir for bovine tuberculosis (TB. Super-ranging may facilitate the spread of disease by increasing both direct interactions between conspecifics, particularly across social groups, and indirect interactions with cattle in their shared environment. Understanding super-ranging behaviour may both improve our understanding of tuberculosis epidemiology and inform future control strategies.

Three-nucleon force contribution in the distorted-wave theory of (d ,p ) reactions

Science.gov (United States)

Timofeyuk, N. K.

2018-05-01

The distorted-wave theory of A (d ,p )B reactions, widely used to analyze experimental data, is based on a Hamiltonian that includes only two-nucleon interactions. However, numerous studies of few-nucleon systems and many modern developments in nuclear structure theory show the importance of the three-nucleon (3 N ) force. The purpose of this paper is to study the contribution of the 3 N force of the simplest possible form to the A (d ,p )B reaction amplitude. This contribution is given by a new term that accounts for the interaction of the neutron and proton in the incoming deuteron with one of the target nucleons. This term involves a new type of nuclear matrix elements containing an infinite number of target excitations in addition to the main part associated with the traditional overlap function between A and B . The nuclear matrix elements are calculated for double-closed shell targets within a mean field theory where target excitations are shown to be equivalent to exchanges between valence and core nucleons. These matrix elements can be readily incorporated into available reaction codes if the 3 N interaction has a spin-independent zero-range form. Distorted-wave calculations are presented for a contact 3 N force with the volume integral fixed by the chiral effective field theory at the next-to-next-to-leading order. For this particular choice, the 3 N contribution is noticeable, especially at high deuteron incident energies. No 3 N effects are seen for incident energies below the Coulomb barrier. The finite range can significantly affect the 3 N contribution to the (d ,p ) cross sections. Finite-range studies require new formal developments and, therefore, their contribution is preliminarily assessed within the plane-wave Born approximation, together with sensitivity to the choice of the deuteron model.

Using demography and movement behavior to predict range expansion of the southern sea otter.

Science.gov (United States)

Tinker, M.T.; Doak, D.F.; Estes, J.A.

2008-01-01

In addition to forecasting population growth, basic demographic data combined with movement data provide a means for predicting rates of range expansion. Quantitative models of range expansion have rarely been applied to large vertebrates, although such tools could be useful for restoration and management of many threatened but recovering populations. Using the southern sea otter (Enhydra lutris nereis) as a case study, we utilized integro-difference equations in combination with a stage-structured projection matrix that incorporated spatial variation in dispersal and demography to make forecasts of population recovery and range recolonization. In addition to these basic predictions, we emphasize how to make these modeling predictions useful in a management context through the inclusion of parameter uncertainty and sensitivity analysis. Our models resulted in hind-cast (1989–2003) predictions of net population growth and range expansion that closely matched observed patterns. We next made projections of future range expansion and population growth, incorporating uncertainty in all model parameters, and explored the sensitivity of model predictions to variation in spatially explicit survival and dispersal rates. The predicted rate of southward range expansion (median = 5.2 km/yr) was sensitive to both dispersal and survival rates; elasticity analysis indicated that changes in adult survival would have the greatest potential effect on the rate of range expansion, while perturbation analysis showed that variation in subadult dispersal contributed most to variance in model predictions. Variation in survival and dispersal of females at the south end of the range contributed most of the variance in predicted southward range expansion. Our approach provides guidance for the acquisition of further data and a means of forecasting the consequence of specific management actions. Similar methods could aid in the management of other recovering populations.

A single particle energies

International Nuclear Information System (INIS)

Bodmer, A.R.; Usmani, Q.N.; Sami, M.

1993-01-01

We consider the binding energies of Λ hypernuclei (HN), in particular the single-particle (s.p.) energy data, which have been obtained for a wide range of HN with mass numbers A ≤ 89 and for orbital angular momenta ell Λ ≤ 4. We briefly review some of the relevant properties of A hypernuclei. These are nuclei Λ A Z with baryon number A in which a single Λ hyperon (baryon number = 1) is bound to an ordinary nucleus A Z consisting of A - 1 nucleons = Z protons + N neutrons. The Λ hyperon is neutral, has spin 1/2, strangeness S = -1, isospin I = O and a mass M Λ = 1116 MeV/c 2 . Although the Λ interacts with a nucleon, its interaction is only about half as strong as that between two nucleons, and thus very roughly V ΛN ∼ 0.5 V NN . As a result, the two-body ΛN system is unbound, and the lightest bound HN is the three-body hypertriton Λ 3 H in which the Λ is bound to a deuteron with the Λ-d separation energy being only ∼ 0.1 MeV corresponding to an exponential tail of radius ∼ 15 fm exclamation point In strong interactions the strangeness S is of course conserved, and the Λ is distinct from the nucleons. In a HN strangeness changes only in the weak decays of the Λ which can decay either via ''free'' pionic decay Λ → N + π or via induced decay Λ + N → N + N which is only possible in the presence of nucleons. Because of the small energy release the pionic decay is strongly suppressed in all but the lightest HN and the induced decay dominates. However, the weak decay lifetime ∼ 10 -10 s is in fact close to the lifetime of a free Λ. Since this is much longer than the strong interaction time ∼ 10 -22 s we can ignore the weak interactions when considering the binding of HN, just as for ordinary nuclei

The ILRS contribution to ITRF2008

Science.gov (United States)

Pavlis, E. C.; Luceri, V.; Sciarretta, C.; Kelm, R.

2009-04-01

Since over two decades, Satellite Laser Ranging (SLR) data contribute to the definition of the Terrestrial Reference Frame (TRF). Until the development of ITRF2000, the contributions were submitted in the form of a set of normal equations or a covariance matrix of station coordinates and their linear rates at a standard epoch. The development of ITRF2005 ushered a new era with the use of weekly or session contributions, allowing greater flexibility in the relative weighting and the combination of information from various techniques. Moreover, the need of a unique, official, representative solution for each Technique Service, based on the rigorous combination of the various Analysis Centers' contributions, gave the opportunity to all techniques to verify, as a first step, the intra-technique solution consistency and, immediately after, to engage in discussions and comparison of the internal procedures, leading to a harmonization and validation of these procedures and the adopted models in the inter-technique context. In many occasions, the time series approach joint with the intra- and inter-technique comparison steps also highlighted differences that previously went unnoticed, and corrected incompatibilities. During the past year we have been preparing the ILRS contribution to a second TRF developed in the same way, the ITRF2008. The ILRS approach is based strictly on the current IERS Conventions 2003 and our internal standards. The Unified Analysis Workshop in 2007 stressed a number of areas where each technique needed to focus more attention in future analyses. In the case of SLR, the primary areas of concern were tracking station biases, extending the data span used in the analysis, and target characteristics. The present re-analysis extends from 1983 to 2008, covering a 25-year period, the longest for any of the contributing techniques; although the network and data quality for the 1983-1993 period are significantly poorer than for the latter years, the overall

Reduction of delayed-neutron contribution to variance-to-mean ratio by application of difference filter technique

International Nuclear Information System (INIS)

Hashimoto, Kengo; Mouri, Tomoaki; Ohtani, Nobuo

1999-01-01

The difference-filtering correlation analysis was applied to time-sequence neutron count data measured in a slightly subcritical assembly, where the Feynman-α analysis suffered from large contribution of delayed neutron to the variance-to-mean ratio of counts. The prompt-neutron decay constant inferred from the present filtering analysis agreed very closely with that by pulsed neutron experiment, and no dependence on the gate-time range specified could be observed. The 1st-order filtering was sufficient for the reduction of the delayed-neutron contribution. While the conventional method requires a choice of analysis formula appropriate to a gate-time range, the present method is applicable to a wide variety of gate-time ranges. (author)

Argentine Population Genetic Structure: Large Variance in Amerindian Contribution

Science.gov (United States)

Seldin, Michael F.; Tian, Chao; Shigeta, Russell; Scherbarth, Hugo R.; Silva, Gabriel; Belmont, John W.; Kittles, Rick; Gamron, Susana; Allevi, Alberto; Palatnik, Simon A.; Alvarellos, Alejandro; Paira, Sergio; Caprarulo, Cesar; Guillerón, Carolina; Catoggio, Luis J.; Prigione, Cristina; Berbotto, Guillermo A.; García, Mercedes A.; Perandones, Carlos E.; Pons-Estel, Bernardo A.; Alarcon-Riquelme, Marta E.

2011-01-01

Argentine population genetic structure was examined using a set of 78 ancestry informative markers (AIMs) to assess the contributions of European, Amerindian, and African ancestry in 94 individuals members of this population. Using the Bayesian clustering algorithm STRUCTURE, the mean European contribution was 78%, the Amerindian contribution was 19.4%, and the African contribution was 2.5%. Similar results were found using weighted least mean square method: European, 80.2%; Amerindian, 18.1%; and African, 1.7%. Consistent with previous studies the current results showed very few individuals (four of 94) with greater than 10% African admixture. Notably, when individual admixture was examined, the Amerindian and European admixture showed a very large variance and individual Amerindian contribution ranged from 1.5 to 84.5% in the 94 individual Argentine subjects. These results indicate that admixture must be considered when clinical epidemiology or case control genetic analyses are studied in this population. Moreover, the current study provides a set of informative SNPs that can be used to ascertain or control for this potentially hidden stratification. In addition, the large variance in admixture proportions in individual Argentine subjects shown by this study suggests that this population is appropriate for future admixture mapping studies. PMID:17177183

Tunable-Range, Photon-Mediated Atomic Interactions in Multimode Cavity QED

Directory of Open Access Journals (Sweden)

Varun D. Vaidya

2018-01-01

Full Text Available Optical cavity QED provides a platform with which to explore quantum many-body physics in driven-dissipative systems. Single-mode cavities provide strong, infinite-range photon-mediated interactions among intracavity atoms. However, these global all-to-all couplings are limiting from the perspective of exploring quantum many-body physics beyond the mean-field approximation. The present work demonstrates that local couplings can be created using multimode cavity QED. This is established through measurements of the threshold of a superradiant, self-organization phase transition versus atomic position. Specifically, we experimentally show that the interference of near-degenerate cavity modes leads to both a strong and tunable-range interaction between Bose-Einstein condensates (BECs trapped within the cavity. We exploit the symmetry of a confocal cavity to measure the interaction between real BECs and their virtual images without unwanted contributions arising from the merger of real BECs. Atom-atom coupling may be tuned from short range to long range. This capability paves the way toward future explorations of exotic, strongly correlated systems such as quantum liquid crystals and driven-dissipative spin glasses.

A Short-Range Distance Sensor with Exceptional Linearity

Science.gov (United States)

Simmons, Steven; Youngquist, Robert

2013-01-01

A sensor has been demonstrated that can measure distance over a total range of about 300 microns to an accuracy of about 0.1 nm (resolution of about 0.01 nm). This represents an exceptionally large dynamic range of operation - over 1,000,000. The sensor is optical in nature, and requires the attachment of a mirror to the object whose distance is being measured. This work resulted from actively developing a white light interferometric system to be used to measure the depths of defects in the Space Shuttle Orbiter windows. The concept was then applied to measuring distance. The concept later expanded to include spectrometer calibration. In summary, broadband (i.e., white) light is launched into a Michelson interferometer, one mirror of which is fixed and one of which is attached to the object whose distance is to be measured. The light emerging from the interferometer has traveled one of two distances: either the distance to the fixed mirror and back, or the distance to the moving mirror and back. These two light beams mix and produce an interference pattern where some wavelengths interfere constructively and some destructively. Sending this light into a spectrometer allows this interference pattern to be analyzed, yielding the net distance difference between the two paths. The unique feature of this distance sensor is its ability to measure accurately distance over a dynamic range of more than one million, the ratio of its range (about 300 microns) to its accuracy (about 0.1 nanometer). Such a large linear operating range is rare and arises here because both amplitude and phase-matching algorithms contribute to the performance. The sensor is limited by the need to attach a mirror of some kind to the object being tracked, and by the fairly small total range, but the exceptional dynamic range should make it of interest.

Fossil preservation and the stratigraphic ranges of taxa

Science.gov (United States)

Foote, M.; Raup, D. M.

1996-01-01

The incompleteness of the fossil record hinders the inference of evolutionary rates and patterns. Here, we derive relationships among true taxonomic durations, preservation probability, and observed taxonomic ranges. We use these relationships to estimate original distributions of taxonomic durations, preservation probability, and completeness (proportion of taxa preserved), given only the observed ranges. No data on occurrences within the ranges of taxa are required. When preservation is random and the original distribution of durations is exponential, the inference of durations, preservability, and completeness is exact. However, reasonable approximations are possible given non-exponential duration distributions and temporal and taxonomic variation in preservability. Thus, the approaches we describe have great potential in studies of taphonomy, evolutionary rates and patterns, and genealogy. Analyses of Upper Cambrian-Lower Ordovician trilobite species, Paleozoic crinoid genera, Jurassic bivalve species, and Cenozoic mammal species yield the following results: (1) The preservation probability inferred from stratigraphic ranges alone agrees with that inferred from the analysis of stratigraphic gaps when data on the latter are available. (2) Whereas median durations based on simple tabulations of observed ranges are biased by stratigraphic resolution, our estimates of median duration, extinction rate, and completeness are not biased.(3) The shorter geologic ranges of mammalian species relative to those of bivalves cannot be attributed to a difference in preservation potential. However, we cannot rule out the contribution of taxonomic practice to this difference. (4) In the groups studied, completeness (proportion of species [trilobites, bivalves, mammals] or genera [crinoids] preserved) ranges from 60% to 90%. The higher estimates of completeness at smaller geographic scales support previous suggestions that the incompleteness of the fossil record reflects loss of

Causes and consequences of range size variation: the influence of traits, speciation, and extinction

Directory of Open Access Journals (Sweden)

Steven M. Vamosi

2012-12-01

Full Text Available The tremendous variation in species richness observed among related clades across the tree of life has long caught the imagination of biologists. Recently, there has been growing attention paid to the possible contribution of range size variation, either alone or in combination with putative key innovations, to these patterns. Here, we review three related topics relevant to range size evolution, speciation, and extinction. First, we provide a brief overview of the debate surrounding patterns and mechanisms for phylogenetic signal in range size. Second, we discuss some recent findings regarding the joint influence of traits and range size on diversification. Finally, we present the preliminary results of a study investigating whether range size is negatively correlated with contemporary extinction risk in flowering plants.

Deuteron-deuteron scattering at 3.0, 3.4 and 3.7 GeV/c, theoretical interpretation in the Glauber model

International Nuclear Information System (INIS)

Ballot, J.L.; L'Huillier, M.; Combes, M.P.; Tatischeff, B.

1984-01-01

An analysis of deuteron-deuteron scattering data at 3.0, 3.4 and 3.7 GeV/c is given in the framework of the Glauber NN multiple scattering model. The model accounts qualitatively well for the larger momentum transfer data. The model cannot reproduce the observed experimental bump at small transfer in the region of missing mass 2GeV/c, because pionic processes have been considered. Nevertheless it shows that the nucleon background is important

Dynamic range studies of the RCA streak tube in the LLL streak camera

International Nuclear Information System (INIS)

Thomas, S.W.; Phillips, G.E.

1979-01-01

As indicated by tests on several cameras, the dynamic range of the Lawrence Livermore Laboratory streak-camera system appears to be about two orders of magnitude greater than those reported for other systems for 10- to 200-ps pulses. The lack of a fine mesh grid in the RCA streak tube used in these cameras probably contributes to a lower system dynamic noise and therefore raises the dynamic range. A developmental tube with a mesh grid was tested and supports this conjecture. Order-of-magnitude variations in input slit width do not affect the spot size on the phosphor or the dynamic range of the RCA tube. (author)

Linking seasonal home range size with habitat selection and movement in a mountain ungulate.

Science.gov (United States)

Viana, Duarte S; Granados, José Enrique; Fandos, Paulino; Pérez, Jesús M; Cano-Manuel, Francisco Javier; Burón, Daniel; Fandos, Guillermo; Aguado, María Ángeles Párraga; Figuerola, Jordi; Soriguer, Ramón C

2018-01-01

Space use by animals is determined by the interplay between movement and the environment, and is thus mediated by habitat selection, biotic interactions and intrinsic factors of moving individuals. These processes ultimately determine home range size, but their relative contributions and dynamic nature remain less explored. We investigated the role of habitat selection, movement unrelated to habitat selection and intrinsic factors related to sex in driving space use and home range size in Iberian ibex, Capra pyrenaica . We used GPS collars to track ibex across the year in two different geographical areas of Sierra Nevada, Spain, and measured habitat variables related to forage and roost availability. By using integrated step selection analysis (iSSA), we show that habitat selection was important to explain space use by ibex. As a consequence, movement was constrained by habitat selection, as observed displacement rate was shorter than expected under null selection. Selection-independent movement, selection strength and resource availability were important drivers of seasonal home range size. Both displacement rate and directional persistence had a positive relationship with home range size while accounting for habitat selection, suggesting that individual characteristics and state may also affect home range size. Ibex living at higher altitudes, where resource availability shows stronger altitudinal gradients across the year, had larger home ranges. Home range size was larger in spring and autumn, when ibex ascend and descend back, and smaller in summer and winter, when resources are more stable. Therefore, home range size decreased with resource availability. Finally, males had larger home ranges than females, which might be explained by differences in body size and reproductive behaviour. Movement, selection strength, resource availability and intrinsic factors related to sex determined home range size of Iberian ibex. Our results highlight the need to integrate

Fermionic NNLO contributions to Bhabha scattering

International Nuclear Information System (INIS)

Actis, S.; Riemann, T.; Czakon, M.; Uniwersytet Slaski, Katowice; Gluza, J.

2007-10-01

We derive the two-loop corrections to Bhabha scattering from heavy fermions using dispersion relations. The double-box contributions are expressed by three kernel functions. Convoluting the perturbative kernels with fermionic threshold functions or with hadronic data allows to determine numerical results for small electron mass m e , combined with arbitrary values of the fermion mass m f in the loop, m 2 e 2 f , or with hadronic insertions. We present numerical results for m f =m μ , m τ ,m top at typical small- and large-angle kinematics ranging from 1 GeV to 500 GeV. (orig.)

The EarthServer Federation: State, Role, and Contribution to GEOSS

Science.gov (United States)

Merticariu, Vlad; Baumann, Peter

2016-04-01

The intercontinental EarthServer initiative has established a European datacube platform with proven scalability: known databases exceed 100 TB, and single queries have been split across more than 1,000 cloud nodes. Its service interface being rigorously based on the OGC "Big Geo Data" standards, Web Coverage Service (WCS) and Web Coverage Processing Service (WCPS), a series of clients can dock into the services, ranging from open-source OpenLayers and QGIS over open-source NASA WorldWind to proprietary ESRI ArcGIS. Datacube fusion in a "mix and match" style is supported by the platform technolgy, the rasdaman Array Database System, which transparently federates queries so that users simply approach any node of the federation to access any data item, internally optimized for minimal data transfer. Notably, rasdaman is part of GEOSS GCI. NASA is contributing its Web WorldWind virtual globe for user-friendly data extraction, navigation, and analysis. Integrated datacube / metadata queries are contributed by CITE. Current federation members include ESA (managed by MEEO sr.l.), Plymouth Marine Laboratory (PML), the European Centre for Medium-Range Weather Forecast (ECMWF), Australia's National Computational Infrastructure, and Jacobs University (adding in Planetary Science). Further data centers have expressed interest in joining. We present the EarthServer approach, discuss its underlying technology, and illustrate the contribution this datacube platform can make to GEOSS.

Solvophobic and solvophilic contributions in the water-to-aqueous guanidinium chloride transfer free energy of model peptides

Science.gov (United States)

Tomar, Dheeraj S.; Ramesh, Niral; Asthagiri, D.

2018-06-01

We study the solvation free energy of two different conformations (helix and extended) of two different peptides (deca-alanine and deca-glycine) in two different solvents (water and aqueous guanidinium chloride, GdmCl). The free energies are obtained using the quasichemical organization of the potential distribution theorem, an approach that naturally provides the repulsive (solvophobic or cavity) and attractive (solvophilic) contributions to solvation. The solvophilic contribution is further parsed into a chemistry contribution arising from solute interaction with the solvent in the first solvation shell and a long-range contribution arising from non-specific interactions between the solute and the solvent beyond the first solvation shell. The cavity contribution is obtained for two different envelopes, ΣS E, which theory helps identify as the solvent excluded volume, and ΣG, a larger envelope beyond which solute-solvent interactions are Gaussian. The ΣS E envelope is independent of the solvent, as expected on the basis of the insensitivity to the solvent type of the distance of closest approach between protein heavy atoms and solvent heavy atoms, but contrary to the intuition based on treating solvent constituents as spheres of some effective radii. For both envelopes, the cavity contribution in water is proportional to the surface area of the envelope. The same does not hold for GdmCl(aq), revealing the limitation of using molecular area to assess solvation energetics. The ΣG-cavity contribution predicts that GdmCl(aq) should favor the more compact state, contrary to the role of GdmCl in unfolding proteins. The chemistry contribution attenuates this effect, but still the net local (chemistry plus ΣG-packing) contribution is inadequate in capturing the role of GdmCl. With the inclusion of the long-range contribution, which is dominated by van der Waals interaction, aqueous GdmCl favors the extended conformation over the compact conformation. Our finding

Contributions to reference systems from Lunar Laser Ranging using the IfE analysis model

Science.gov (United States)

Hofmann, Franz; Biskupek, Liliane; Müller, Jürgen

2018-01-01

Lunar Laser Ranging (LLR) provides various quantities related to reference frames like Earth orientation parameters, coordinates and velocities of ground stations in the Earth-fixed frame and selenocentric coordinates of the lunar retro-reflectors. This paper presents the recent results from LLR data analysis at the Institut für Erdmessung, Leibniz Universität Hannover, based on all LLR data up to the end of 2016. The estimates of long-periodic nutation coefficients with periods between 13.6 days and 18.6 years are obtained with an accuracy in the order of 0.05-0.7 milliarcseconds (mas). Estimations of the Earth rotation phase Δ UT are accurate at the level of 0.032 ms if more than 14 normal points per night are included. The tie between the dynamical ephemeris frame to the kinematic celestial frame is estimated from pure LLR observations by two angles and their rates with an accuracy of 0.25 and 0.02 mas per year. The estimated station coordinates and velocities are compared to the ITRF2014 solution and the geometry of the retro-reflector network with the DE430 solution. The given accuracies represent 3 times formal errors of the parameter fit. The accuracy for Δ UT is based on the standard deviation of the estimates with respect to the reference C04 solution.

Genetic and Environmental Contributions to the Development of Childhood Aggression

Science.gov (United States)

Lubke, Gitta H.; McArtor, Daniel B.; Boomsma, Dorret I.; Bartels, Meike

2018-01-01

Longitudinal data from a large sample of twins participating in the Netherlands Twin Register (n = 42,827, age range 3-16) were analyzed to investigate the genetic and environmental contributions to childhood aggression. Genetic auto-regressive (simplex) models were used to assess whether the same genes are involved or whether new genes come into…

Grounded theory: building a middle-range theory in nursing

Directory of Open Access Journals (Sweden)

Maria João Fernandes

2015-03-01

Full Text Available The development of nursing as a discipline results from a boom of investigations underway for nearly a century, and of the construction of theories that have arisen during the 1950’s, with greater relevance since the 1960’s. Giving continuation to the production of knowledge in nursing and seeking to contribute to the increase in the number of explanatory theories of the functional content of nurses, there is interest in answering the question: how can a middle-range theory in nursing be built that explains the nurse-elderly interaction in a successful aging process? As well, we address the goal of describing the process of building a middle-range theory in nursing. Middle-range theory refers to a qualitative paradigm study of inductive thinking, developed in the context of primary health care. The information was collected through participant observation and interviews. Method of analysis grounded theory by Corbin and Strauss(1 was followed, utilizing the triangulation of data and theoretical sampling. Grounded theory has become a method of analysis which facilitates the understanding and explanation of the phenomenon under study. By making clear the nature and process of the nurse-elderly interaction in the selected context and within the context of successful aging, a middle-range theory proposal emerged.

CONTRIBUTION OF DIFFERENT PARTICLES MEASURED WITH TRACK ETCHED DETECTORS ONBOARD ISS.

Science.gov (United States)

Ambrožová, I; Davídková, M; Brabcová, K Pachnerová; Tolochek, R V; Shurshakov, V A

2017-09-29

Cosmic radiation consists of primary high-energy galactic and solar particles. When passing through spacecraft walls and astronauts' bodies, the spectrum becomes even more complex due to generating of secondary particles through fragmentation and nuclear interactions. Total radiation exposure is contributed by both these components. With an advantage, space research uses track etched detectors from the group of passive detectors visualizing the tracks of particles, in this case by etching. The detectors can discriminate between various components of cosmic radiation. A method is introduced for the separation of the different types of particles according to their range using track etched detectors. The method is demonstrated using detectors placed in Russian segment of the International Space Station in 2009. It is shown that the primary high-energy heavy ions with long range contribute up to 56% of the absorbed dose and up to 50% to the dose equivalent. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Investigation of fractional momentum transfer: measurement of forward recoil ranges in 16O + natTm collisions

International Nuclear Information System (INIS)

Singh, Pushpendra P.; Unnati; Sharma, Manoj Kumar; Singh, B.P.; Prasad, R.; Rakesh Kumar; Golda, K.S.; Bhardwaj, H.D.

2006-01-01

For better understanding of complete fusion and incomplete fusion in heavy ion reactions a programme of precise measurements of excitation functions, recoil range distribution and angular distributions of recoils has been undertaken. In the present contribution the recoil range distribution for the residues have been measured at ≅ 6 MeV/nucleon, using recoil-catcher technique followed by off-line gamma-spectroscopy

Ranging Behaviour of Commercial Free-Range Broiler Chickens 2: Individual Variation.

Science.gov (United States)

Taylor, Peta S; Hemsworth, Paul H; Groves, Peter J; Gebhardt-Henrich, Sabine G; Rault, Jean-Loup

2017-07-20

Little is known about broiler chicken ranging behaviour. Previous studies have monitored ranging behaviour at flock level but whether individual ranging behaviour varies within a flock is unknown. Using Radio Frequency Identification technology, we tracked 1200 individual ROSS 308 broiler chickens across four mixed sex flocks in two seasons on one commercial farm. Ranging behaviour was tracked from first day of range access (21 days of age) until 35 days of age in winter flocks and 44 days of age in summer flocks. We identified groups of chickens that differed in frequency of range visits: chickens that never accessed the range (13 to 67% of tagged chickens), low ranging chickens (15 to 44% of tagged chickens) that accounted for range visits and included chickens that used the range only once (6 to 12% of tagged chickens), and high ranging chickens (3 to 9% of tagged chickens) that accounted for 33 to 50% of all range visits. Males spent longer on the range than females in winter ( p ranging behaviour may help optimise ranging opportunities in free-range systems and is important to elucidate the potential welfare implications of ranging.

Connected and disconnected quark contributions to hadron spin

International Nuclear Information System (INIS)

Chambers, A.J.

2014-12-01

By introducing an external spin operator to the fermion action, the quark spin fractions of hadrons are determined from the linear response of the hadron energies using the Feynman-Hellmann (FH) theorem. At our SU(3)-flavour symmetric point, we find that the connected quark spin fractions are universally in the range 55-70% for vector mesons and octet and decuplet baryons. There is an indication that the amount of spin suppression is quite sensitive to the strength of SU(3) breaking. We also present first preliminary results applying the FH technique to calculations of quark-line disconnected contributions to hadronic matrix elements of axial and tensor operators. At the SU(3)-flavour symmetric point we find a small negative contribution to the nucleon spin from disconnected quark diagrams, while the corresponding tensor matrix elements are consistent with zero.

A view on thermodynamics of concentrated electrolytes: Modification necessity for electrostatic contribution of osmotic coefficient

Science.gov (United States)

Sahu, Jyoti; Juvekar, Vinay A.

2018-05-01

Prediction of the osmotic coefficient of concentrated electrolytes is needed in a wide variety of industrial applications. There is a need to correctly segregate the electrostatic contribution to osmotic coefficient from nonelectrostatic contribution. This is achieved in a rational way in this work. Using the Robinson-Stokes-Glueckauf hydrated ion model to predict non-electrostatic contribution to the osmotic coefficient, it is shown that hydration number should be independent of concentration so that the observed linear dependence of osmotic coefficient on electrolyte concentration in high concentration range could be predicted. The hydration number of several electrolytes (LiCl, NaCl, KCl, MgCl2, and MgSO4) has been estimated by this method. The hydration number predicted by this model shows correct dependence on temperature. It is also shown that the electrostatic contribution to osmotic coefficient is underpredicted by the Debye-Hückel theory at concentration beyond 0.1 m. The Debye-Hückel theory is modified by introducing a concentration dependent hydrated ionic size. Using the present analysis, it is possible to correctly estimate the electrostatic contribution to the osmotic coefficient, beyond the range of validation of the D-H theory. This would allow development of a more fundamental model for electrostatic interaction at high electrolyte concentrations.

Characterization of advanced piezoelectric materials in the wide temperature range

Energy Technology Data Exchange (ETDEWEB)

Burianova, L.; Kopal, A.; Nosek, J

2003-05-25

We report about methods and results of our measurements of piezoelectric, dielectric and elastic properties of piezoelectric materials like crystals, ceramics, composites, polymers and thin layer composites. Among the methods, used in our laboratories are: the resonance method working in the temperature range 208-358 K, hydrostatic methods, both static and dynamic in the range 273-333 K, laser interferometric methods, using single and double-beam interferometer, working at room temperature, single and double-beam micro-interferometers, working inside of optical cryostat in the range 150-330 K, and pulse echo method for measurements of elastic coefficients, using ultrasonic set, working at room temperature. In our earlier papers we reported about some of our results of piezoelectric measurements of PZT ceramics using resonance method and laser interferometric method. The results of both methods were in good agreement. Now, the measurements are realized on 0-3 ceramic-polymer composites and thin layer composites. It is well known, that both intrinsic (material) and extrinsic (domain structure) contributions to properties of ferroelectric samples have characteristic, sometimes rather strong, temperature dependence. Therefore, any extension of temperature range of the above mentioned methods is welcomed.

Tunable optical coherence tomography in the infrared range using visible photons

Science.gov (United States)

Paterova, Anna V.; Yang, Hongzhi; An, Chengwu; Kalashnikov, Dmitry A.; Krivitsky, Leonid A.

2018-04-01

Optical coherence tomography (OCT) is an appealing technique for bio-imaging, medicine, and material analysis. For many applications, OCT in mid- and far-infrared (IR) leads to significantly more accurate results. Reported mid-IR OCT systems require light sources and photodetectors which operate in mid-IR range. These devices are expensive and need cryogenic cooling. Here, we report a proof-of-concept demonstration of a wavelength tunable IR OCT technique with detection of only visible range photons. Our method is based on the nonlinear interference of frequency correlated photon pairs. The nonlinear crystal, introduced in the Michelson-type interferometer, generates photon pairs with one photon in the visible and another in the IR range. The intensity of detected visible photons depends on the phase and loss of IR photons, which interact with the sample under study. This enables us to characterize sample properties and perform imaging in the IR range by detecting visible photons. The technique possesses broad wavelength tunability and yields a fair axial and lateral resolution, which can be tailored to the specific application. The work contributes to the development of versatile 3D imaging and material characterization systems working in a broad range of IR wavelengths, which do not require the use of IR-range light sources and photodetectors.

Coulomb breakup of 31Ne using finite range DWBA

International Nuclear Information System (INIS)

Shubhchintak; Chatterjee, R.

2013-01-01

Coulomb breakup of nuclei away from the valley of stability have been one of the most successful probes to unravel their structure. However, it is only recently that one is venturing into medium mass nuclei like 23 O and 31 Ne. This is a very new and exciting development which has expanded the field of light exotic nuclei to the deformed medium mass region. In this contribution, an extension of the previously proposed theory of Coulomb breakup within the post-form finite range distorted wave Born approximation to include deformation of the projectile is reported

Remarks on the pion–nucleon σ-term

Energy Technology Data Exchange (ETDEWEB)

Hoferichter, Martin, E-mail: mhofer@uw.edu [Institute for Nuclear Theory, University of Washington, Seattle, WA 98195-1550 (United States); Ruiz de Elvira, Jacobo; Kubis, Bastian [Helmholtz-Institut für Strahlen- und Kernphysik (Theorie) and Bethe Center for Theoretical Physics, Universität Bonn, D-53115 Bonn (Germany); Meißner, Ulf-G. [Helmholtz-Institut für Strahlen- und Kernphysik (Theorie) and Bethe Center for Theoretical Physics, Universität Bonn, D-53115 Bonn (Germany); Institut für Kernphysik, Institute for Advanced Simulation, Jülich Center for Hadron Physics, JARA-HPC, and JARA-FAME, Forschungszentrum Jülich, D-52425 Jülich (Germany)

2016-09-10

The pion–nucleon σ-term can be stringently constrained by the combination of analyticity, unitarity, and crossing symmetry with phenomenological information on the pion–nucleon scattering lengths. Recently, lattice calculations at the physical point have been reported that find lower values by about 3σ with respect to the phenomenological determination. We point out that a lattice measurement of the pion–nucleon scattering lengths could help resolve the situation by testing the values extracted from spectroscopy measurements in pionic atoms.

Remarks on the pion–nucleon σ-term

Directory of Open Access Journals (Sweden)

Martin Hoferichter

2016-09-01

Full Text Available The pion–nucleon σ-term can be stringently constrained by the combination of analyticity, unitarity, and crossing symmetry with phenomenological information on the pion–nucleon scattering lengths. Recently, lattice calculations at the physical point have been reported that find lower values by about 3σ with respect to the phenomenological determination. We point out that a lattice measurement of the pion–nucleon scattering lengths could help resolve the situation by testing the values extracted from spectroscopy measurements in pionic atoms.

Remarks on the pion-nucleon σ-term

Science.gov (United States)

Hoferichter, Martin; Ruiz de Elvira, Jacobo; Kubis, Bastian; Meißner, Ulf-G.

2016-09-01

The pion-nucleon σ-term can be stringently constrained by the combination of analyticity, unitarity, and crossing symmetry with phenomenological information on the pion-nucleon scattering lengths. Recently, lattice calculations at the physical point have been reported that find lower values by about 3σ with respect to the phenomenological determination. We point out that a lattice measurement of the pion-nucleon scattering lengths could help resolve the situation by testing the values extracted from spectroscopy measurements in pionic atoms.

Cascade in muonic and pionic atoms with Z = 1

International Nuclear Information System (INIS)

Markushin, V.E.

1999-01-01

Recent theoretical and experimental studies of the exotic atoms with Z = 1 are reviewed. An interplay between the atomic internal and external degrees of freedom is essential for a good description of the atomic cascade. The perspective of ab initio cascade calculations is outlined

Women in numbers Europe II contributions to number theory and arithmetic geometry

CERN Document Server

Ozman, Ekin; Johnson-Leung, Jennifer; Newton, Rachel

2018-01-01

Inspired by the September 2016 conference of the same name, this second volume highlights recent research in a wide range of topics in contemporary number theory and arithmetic geometry. Research reports from projects started at the conference, expository papers describing ongoing research, and contributed papers from women number theorists outside the conference make up this diverse volume. Topics cover a broad range of topics such as arithmetic dynamics, failure of local-global principles, geometry in positive characteristics, and heights of algebraic integers. The use of tools from algebra, analysis and geometry, as well as computational methods exemplifies the wealth of techniques available to modern researchers in number theory. Exploring connections between different branches of mathematics and combining different points of view, these papers continue the tradition of supporting and highlighting the contributions of women number theorists at a variety of career stages. Perfect for students and researche...

Cantilever contribution to the total electrostatic force measured with the atomic force microscope

International Nuclear Information System (INIS)

Guriyanova, Svetlana; Golovko, Dmytro S; Bonaccurso, Elmar

2010-01-01

The atomic force microscope (AFM) is a powerful tool for surface imaging at the nanometer scale and surface force measurements in the piconewton range. Among long-range surface forces, the electrostatic forces play a predominant role. They originate if the electric potentials of the substrate and of the tip of the AFM cantilever are different. A quantitative interpretation of the AFM signal is often difficult because it depends in a complicated fashion on the cantilever–tip–surface geometry. Since the electrostatic interaction is a long-range interaction, the cantilever, which is many microns from the surface, contributes to the total electrostatic force along with the tip. Here we present results of the electrostatic interaction between a conducting flat surface and horizontal or tilted cantilevers, with and without tips, at various distances from the surface. As addressed in a previous work, we show that the contribution of the cantilever to the overall force cannot be neglected. Based on a predictive model and on 3D confocal measurements, we discuss the influence of the tilting angle of the cantilever

Project management and performance management: potential transdisciplinary contributions

Directory of Open Access Journals (Sweden)

Gerrit van der Waldt

2012-12-01

Full Text Available As project management and performance management as management applications gain momentum in public sector settings, the question often arise as to if, how, and when these applications should complement each other in various policy implementation and service delivery initiatives. Answers to this question should be sought from various vantage points or perspectives. These vantage points may range from macro, meso, micro as well as theoretical-methodological perspectives. The purpose of this paper is to unlock the potential for transdisciplinary contributions between Project Management and Performance Management by focusing on the methodologies, functional areas, and practical applications of both management disciplines. It is argued that the respective methodologies and their processes should be unpacked to identify the timing or moment when each discipline could, and should, make a contribution to the success of the other. This will add value to the theoretical underpinnings and practical applications of both study domains in the public sector. The respective contributions are illustrated by means of application realities of both management practices in the South African Public Service. Keywords: project management, performance management, Public Sector applications, transdisciplinarity Disciplines: project management, performance management

Analysis of albumin Raman scattering in visible and near-infrared ranges

Science.gov (United States)

Lykina, Anastasia A.; Artemyev, Dmitry N.

2018-04-01

In this work the analysis of the shape and intensity of albumin Raman signals in visible and near-IR ranges was carried out. The experimental setup using lasers from the visible region first of all excites the fluorescence of the albumin solution, the main contribution to which is produced by sodium chloride, which is a component of the tested sample. At the same time, lasers from the near-infrared range excited the Raman signal of albumin most effectively. It was found that the highest ratio of Raman scattering to autofluorescence intensities in the detected signal was obtained using a laser with a wavelength of 1064 nm. To determine the albumin solution concentration by type of spectrum, a regression approach with the projection to latent structures method was applied. The lowest predicted error of albumin concentration of 2-3 g/l was obtained by using the near-infrared range lasers.

Entropy and long-range memory in random symbolic additive Markov chains.

Science.gov (United States)

Melnik, S S; Usatenko, O V

2016-06-01

The goal of this paper is to develop an estimate for the entropy of random symbolic sequences with elements belonging to a finite alphabet. As a plausible model, we use the high-order additive stationary ergodic Markov chain with long-range memory. Supposing that the correlations between random elements of the chain are weak, we express the conditional entropy of the sequence by means of the symbolic pair correlation function. We also examine an algorithm for estimating the conditional entropy of finite symbolic sequences. We show that the entropy contains two contributions, i.e., the correlation and the fluctuation. The obtained analytical results are used for numerical evaluation of the entropy of written English texts and DNA nucleotide sequences. The developed theory opens the way for constructing a more consistent and sophisticated approach to describe the systems with strong short-range and weak long-range memory.

Global patterns of protection of elevational gradients in mountain ranges.

Science.gov (United States)

Elsen, Paul R; Monahan, William B; Merenlender, Adina M

2018-05-21

Protected areas (PAs) that span elevational gradients enhance protection for taxonomic and phylogenetic diversity and facilitate species range shifts under climate change. We quantified the global protection of elevational gradients by analyzing the elevational distributions of 44,155 PAs in 1,010 mountain ranges using the highest resolution digital elevation models available. We show that, on average, mountain ranges in Africa and Asia have the lowest elevational protection, ranges in Europe and South America have intermediate elevational protection, and ranges in North America and Oceania have the highest elevational protection. We use the Convention on Biological Diversity's Aichi Target 11 to assess the proportion of elevational gradients meeting the 17% suggested minimum target and examine how different protection categories contribute to elevational protection. When considering only strict PAs [International Union for Conservation of Nature (IUCN) categories I-IV, n = 24,706], nearly 40% of ranges do not contain any PAs, roughly half fail to meet the 17% target at any elevation, and ∼75% fail to meet the target throughout ≥50% of the elevational gradient. Observed elevational protection is well below optimal, and frequently below a null model of elevational protection. Including less stringent PAs (IUCN categories V-VI and nondesignated PAs, n = 19,449) significantly enhances elevational protection for most continents, but several highly biodiverse ranges require new or expanded PAs to increase elevational protection. Ensuring conservation outcomes for PAs with lower IUCN designations as well as strategically placing PAs to better represent and connect elevational gradients will enhance ecological representation and facilitate species range shifts under climate change. Copyright © 2018 the Author(s). Published by PNAS.

Urban PM in Eastern Germany: Source apportionment and contributions from different spatial scales

Science.gov (United States)

van Pinxteren, D.; Fomba, K. W.; Mothes, F.; Spindler, G.; Herrmann, H.

2017-12-01

Understanding the contributions of particulate matter (PM) sources and the source areas impacting total PM levels in a city are important requirements for further developing clean air policies and efficient abatement strategies. This presentation reports on two studies in Eastern Germany providing a detailed picture of present-day urban PM sources and discriminating contributions of local, regional and long-range sources. The "Leipzig Aerosol 2013-15" study yielded contributions of 12 sources to coarse, fine, and ultrafine particles, resolved by Positive Matrix Factorization (PMF) from comprehensive chemical speciation of 5-stage Berner impactor samples at 4 different sites in the Leipzig area. Dominant winter-time sources were traffic exhaust and non-exhaust emissions, secondary aerosol formation, and combustion emissions from both biomass and coal burning with different relative importance in different particle size ranges. Local sources dominated PM levels in ultrafine and coarse particles (60% - 80%) while high mass concentrations in accumulation mode particles mainly resulted from regional import into the city (70%). The "PM-East" study compiled PM10 mass and constituents' concentrations at 10 urban and rural sites in Eastern Germany during winter 2016/17, which included a 3-week episode of frequent exceedances of the PM10 limit value. PMF source apportionment is performed for a subset of the sites, including the city of Berlin. Contributions from short-, mid-, and long-range sources, including trans-boundary pollution import from neighbouring countries, are quantitatively assessed by advanced back trajectory statistical methods. Data analysis in PM-East is ongoing and final results will be available by November. Funding is acknowledged from 4 federal states of Germany: Berlin Senate Department for Environment, Transport and Climate Protection; Saxon State Office for Environment, Agriculture and Geology; State Agency for Environment, Nature Conservation and

Effect of electronic contribution on temperature-dependent thermal transport of antimony telluride thin film

Energy Technology Data Exchange (ETDEWEB)

Lee, Won-Yong; Park, No-Won [Department of Physics, Chung-Ang University, Seoul 156-756 (Korea, Republic of); Hong, Ji-Eun [Department of Materials Engineering, Chungnam National University, Daejeon 305-764 (Korea, Republic of); Yoon, Soon-Gil, E-mail: sgyoon@cnu.ac.kr [Department of Materials Engineering, Chungnam National University, Daejeon 305-764 (Korea, Republic of); Koh, Jung-Hyuk [School of Electrical and Electronics Engineering, Chung-Ang University, Seoul 156-756 (Korea, Republic of); Lee, Sang-Kwon, E-mail: sangkwonlee@cau.ac.kr [Department of Physics, Chung-Ang University, Seoul 156-756 (Korea, Republic of)

2015-01-25

Highlights: • We investigated thermal transport of the antimony telluride thin films. • The contribution of the electronic thermal conductivity increased up to ∼77% at 300 K. • We theoretically analyze and explain the high contribution of electronic component. - Abstract: We study the theoretical and experimental characteristics of thermal transport of 100 nm and 500 nm-thick antimony telluride (Sb{sub 2}Te{sub 3}) thin films prepared by radio frequency magnetron sputtering. The thermal conductivity was measured at temperatures ranging from 20 to 300 K, using four-point-probe 3-ω method. Out-of-plane thermal conductivity of the Sb{sub 2}Te{sub 3} thin film was much lesser in comparison to the bulk material in the entire temperature range, confirming that the phonon- and electron-boundary scattering are enhanced in thin films. Moreover, we found that the contribution of the electronic thermal conductivity (κ{sub e}) in total thermal conductivity (κ) linearly increased up to ∼77% at 300 K with increasing temperature. We theoretically analyze and explain the high contribution of electronic component of thermal conductivity towards the total thermal conductivity of the film by a modified Callaway model. Further, we find the theoretical model predictions to correspond well with the experimental results.

Improved Feature Detection in Fused Intensity-Range Images with Complex SIFT (ℂSIFT

Directory of Open Access Journals (Sweden)

Boris Jutzi

2011-09-01

Full Text Available The real and imaginary parts are proposed as an alternative to the usual Polar representation of complex-valued images. It is proven that the transformation from Polar to Cartesian representation contributes to decreased mutual information, and hence to greater distinctiveness. The Complex Scale-Invariant Feature Transform (ℂSIFT detects distinctive features in complex-valued images. An evaluation method for estimating the uniformity of feature distributions in complex-valued images derived from intensity-range images is proposed. In order to experimentally evaluate the proposed methodology on intensity-range images, three different kinds of active sensing systems were used: Range Imaging, Laser Scanning, and Structured Light Projection devices (PMD CamCube 2.0, Z+F IMAGER 5003, Microsoft Kinect.

Population genetics and the evolution of geographic range limits in an annual plant.

Science.gov (United States)

Moeller, David A; Geber, Monica A; Tiffin, Peter

2011-10-01

Abstract Theoretical models of species' geographic range limits have identified both demographic and evolutionary mechanisms that prevent range expansion. Stable range limits have been paradoxical for evolutionary biologists because they represent locations where populations chronically fail to respond to selection. Distinguishing among the proposed causes of species' range limits requires insight into both current and historical population dynamics. The tools of molecular population genetics provide a window into the stability of range limits, historical demography, and rates of gene flow. Here we evaluate alternative range limit models using a multilocus data set based on DNA sequences and microsatellites along with field demographic data from the annual plant Clarkia xantiana ssp. xantiana. Our data suggest that central and peripheral populations have very large historical and current effective population sizes and that there is little evidence for population size changes or bottlenecks associated with colonization in peripheral populations. Whereas range limit populations appear to have been stable, central populations exhibit a signature of population expansion and have contributed asymmetrically to the genetic diversity of peripheral populations via migration. Overall, our results discount strictly demographic models of range limits and more strongly support evolutionary genetic models of range limits, where adaptation is prevented by a lack of genetic variation or maladaptive gene flow.

Contribution of fungal spores to particulate matter in a tropical rainforest

International Nuclear Information System (INIS)

Zhang Ting; Chan Chuenyu; Zhang Yinan; Zhang Zhisheng; Lin Mang; Sang Xuefang; Engling, Guenter; Li, Y D; Li, Yok-Sheung

2010-01-01

The polyols arabitol and mannitol, recently proposed as source tracers for fungal spores, were used in this study to estimate fungal contributions to atmospheric aerosol. Airborne particulate matter (PM 2.5 and PM 10 ) was collected at Jianfengling Mountain, a tropical rainforest on Hainan Island situated off the south China coast, during spring and analyzed for arabitol and mannitol by high-performance anion exchange chromatography with pulsed amperometric detection (HPAEC-PAD). The average concentrations of arabitol and mannitol exhibited high values with averages of 7.0 and 16.0 ng m -3 respectively in PM 2.5 and 44.0 and 71.0 ng m -3 in PM 10 . The two tracers correlated well with each other, especially in the coarse mode aerosol (PM 2.5-10 ), indicating they were mainly associated with coarse aerosol particles and had common sources. Arabitol and mannitol in PM 10 showed significant positive correlations with relative humidity, as well as positive correlations with average temperature, suggesting a wet emissions mechanism of biogenic aerosol in the form of fungal spores. We made estimations of the contribution of fungal spores to ambient PM mass and to organic carbon, based on the observed ambient concentrations of these two tracers. The relative contributions of fungal spores to the PM 10 mass were estimated to range from 1.6 to 18.2%, with a rather high mean value of 7.9%, and the contribution of fungal spores to organic carbon in PM 10 ranged from 4.64 to 26.1%, with a mean value of 12.1%, implying that biological processes are important sources of atmospheric aerosol.

Motion range assessment in Rheumatoid Arthritis: a literature review

Directory of Open Access Journals (Sweden)

Melissa Andrea Jeannet Michaelsen Cardoso Mezzari

2017-06-01

Full Text Available Objective: The aim of this review is to describe the methods used for range of motion (ROM assessment in Rheumatoid Arthritis (RA in order to assist in the identification of the main limitations experienced by patients and thus contribute to the specific treatment of the most affected joints. Method: The methodology used was a critical review of the literature and the search was conducted in the capes portal, specifically in health care databases. The two MeSH descriptors “rheumatoid arthritis” and “mobility limitation” were used in the search, and also the term “range of motion”. Results: A total of 774 articles were found in the review and 446 were preselected based on title and abstract contents. After reading, 403 articles did not meet the inclusion criteria set in the study and were excluded. Thus, 43 articles were selected, which are summarized in a standardized manner. The studies do not approach the mobility of joints of RA patients, but they have in common the inclusion of ROM assessment to monitor the disease in a manner that is directly related to the function of the joints, especially the most compromised ones. Conclusion: We suggest the realization of thorough studies on joint involvement in order to outline interventions for preventing deformities generated by RA that compromise the quality of life of these patients. The studies could also contribute to disseminate such assessment practices among the multidisciplinary teams that provide assistance to these patients, optimizing the long-term care plan and taking into account the chronicity of the condition.

Short-range correlations in an extended time-dependent mean-field theory

International Nuclear Information System (INIS)

Madler, P.

1982-01-01

A generalization is performed of the time-dependent mean-field theory by an explicit inclusion of strong short-range correlations on a level of microscopic reversibility relating them to realistic nucleon-nucleon forces. Invoking a least action principle for correlated trial wave functions, equations of motion for the correlation functions and the single-particle model wave function are derived in lowest order of the FAHT cluster expansion. Higher order effects as well as long-range correlations are consider only to the extent to which they contribute to the mean field via a readjusted phenomenological effective two-body interaction. The corresponding correlated stationary problem is investigated and appropriate initial conditions to describe a heavy ion reaction are proposed. The singleparticle density matrix is evaluated

Molecular-scale tribology of amorphous carbon coatings: effects of film thickness, adhesion, and long-range interactions.

Science.gov (United States)

Gao, G T; Mikulski, Paul T; Harrison, Judith A

2002-06-19

Classical molecular dynamics simulations have been conducted to investigate the atomic-scale friction and wear when hydrogen-terminated diamond (111) counterfaces are in sliding contact with diamond (111) surfaces coated with amorphous, hydrogen-free carbon films. Two films, with approximately the same ratio of sp(3)-to-sp(2) carbon, but different thicknesses, have been examined. Both systems give a similar average friction in the load range examined. Above a critical load, a series of tribochemical reactions occur resulting in a significant restructuring of the film. This restructuring is analogous to the "run-in" observed in macroscopic friction experiments and reduces the friction. The contribution of adhesion between the probe (counterface) and the sample to friction was examined by varying the saturation of the counterface. Decreasing the degree of counterface saturation, by reducing the hydrogen termination, increases the friction. Finally, the contribution of long-range interactions to friction was examined by using two potential energy functions that differ only in their long-range forces to examine friction in the same system.

Disconnected-Sea Quarks Contribution to Nucleon Electromagnetic Form Factors

Science.gov (United States)

Sufian, Raza Sabbir

We present comprehensive analysis of the light and strange disconnected-sea quarks contribution to the nucleon electric and magnetic form factors. The lattice QCD estimates of strange quark magnetic moment GsM (0) = -0.064(14)(09) microN and the mean squared charge radius E = -0.0043(16)(14) fm2 are more precise than any existing experimental measurements and other lattice calculations. The lattice QCD calculation includes ensembles across several lattice volumes and lattice spacings with one of the ensembles at the physical pion mass. We have performed a simultaneous chiral, infinite volume, and continuum extrapolation in a global fit to calculate results in the continuum limit. We find that the combined light-sea and strange quarks contribution to the nucleon magnetic moment is -0.022(11)(09) microN and to the nucleon mean square charge radius is -0.019(05)(05) fm 2. The most important outcome of this lattice QCD calculation is that while the combined light-sea and strange quarks contribution to the nucleon magnetic moment is small at about 1%, a negative 2.5(9)% contribution to the proton charge radius and a relatively larger positive 16.3(6.1)% contribution to the neutron charge radius come from the sea quarks in the nucleon. For the first time, by performing global fits, we also give predictions of the light-sea and strange quarks contributions to the nucleon electric and magnetic form factors at the physical point and in the continuum and infinite volume limits in the momentum transfer range of 0 ≤ Q2 ≤ 0.5 GeV2.

Deuteron stripping on beryllium target in the 100-2300 MeV energy range

International Nuclear Information System (INIS)

Lecolley, J.F.; Varignon, C.; Durand, D.; Le Brun, C.; Lecolley, F.R.; Lefebvres, F.; Louvel, M.; Thun, J.; Borne, F.; Martinez, E.; Menard, S.; Pras, P.; Boudard, A.; Duchazeaubeneix, J.C.; Durand, J.M.; Frehaut, J.; Hanappe, F.; Ledoux, X.; Legrain, R.; Leray, S.; Milleret, G.; Patin, Y.; Stuttge, L.; Terrien, Y.

1999-01-01

Cross sections for stripping and dissociation of deuterons interacting with Be targets in the 100-2300 MeV energy range have been measured. Comparisons with model calculations suggest a dominant contribution of the stripping process. It is also shown that the deuteron break-up cross section exhibits the same energy dependence as the nucleon-nucleon cross section. (orig.)

Teledyne's historical contribution to developing superconductivity

International Nuclear Information System (INIS)

McDonald, W.K.

1986-01-01

Of the contributions made to superconductivity by Teledyne Wah Change Albany (TWCA), two have been outstanding. The first is the establishment of a stable and low cost NbTi alloy. Estimates of cost savings passed along to conductor manufacturers and, subsequently, to the applications of superconductivity range between $24,000,000 and $31,000,000 over the years from 1980 to present. Secondly, TWCA has understood the necessity of cooperating with the scientific community in order to understand critical relationships of metallurgy to superconductivity characteristics. The knowledge gained is integrated into alloy production on a commercial basis. The most notable example is the recent increase in current density prospects for the proposed Superconducting Super Collider

Solitons in bosonic effective theories versus underlying fermions

International Nuclear Information System (INIS)

Jayaraman, T.; Sharatchandra, H.S.

1984-11-01

We argue, using the Gross-Neveu model as an example, for the following picture: a baryon of baryon number B occasionally looks like a configuration of 3(B-W) quarks bound to a soliton (of the pionic condensate) with an integer winding number W. The Skyrmion picture in the original form is relevant if the lowest lying level of baryon number B is dominantly a soliton instead of a configuration of 3B quarks. Our techniques do not depend upon semi-classical or adiabatic approximations. (author)

Predictions of High Energy Experimental Results

Directory of Open Access Journals (Sweden)

Comay E.

2010-10-01

Full Text Available Eight predictions of high energy experimental results are presented. The predictions contain the $Sigma ^+$ charge radius and results of two kinds of experiments using energetic pionic beams. In addition, predictions of the failure to find the following objects are presented: glueballs, pentaquarks, Strange Quark Matter, magnetic monopoles searched by their direct interaction with charges and the Higgs boson. The first seven predictions rely on the Regular Charge-Monopole Theory and the last one relies on mathematical inconsistencies of the Higgs Lagrangian density.

Proceedings

International Nuclear Information System (INIS)

Lee, H.C.; Saharia, A.N.; Thomas, A.W.

1979-12-01

Invited talks presented at a two-week workshop on pion-nucleon interactions are briefly presented and a summary of the discussions that took place is added. Topics covered include quantum chromodynamics and the weak NNπ vertex, pionic effects in the weak decays of nuclei, the isobar-doorway approach to the pion-nucleus interaction, multiple scattering approaches, the phenomenology of non-elastic reactions within the isobar-doorway picture, a field theory of pion-nucleus interaction, and the quark structure of the nucleon in nuclei. (LL)

Foreign and Domestic Contributions to Springtime Ozone Pollution over China

Science.gov (United States)

Ni, R.; Lin, J.; Yan, Y.; Lin, W.; Chen, H.

2017-12-01

Ozone is a critical air pollutant that damages human health and vegetation. Previous studies for the United States and Europe have shown large influences of foreign emissions on domestic ozone levels, whereas the relative contributions of foreign versus domestic emissions are much less clear for China. Here, we use a global-regional two-way coupled model system based on GEOS-Chem to quantify the contributions to springtime ozone over China from anthropogenic emissions in major source regions across the globe. Our results indicate considerable influences of foreign anthropogenic pollution on China's ozone pollution. Together, foreign anthropogenic emissions enhance springtime surface ozone over China by 3 12 ppb. Of all ozone over China produced by global anthropogenic emissions, foreign emissions contribute 40% near the surface, and the contribution increases with altitude until a value of 80% in the upper troposphere. Impact from Japan and Korea is 1 2 ppb over east coastal regions, and negligible in inland. Anthropogenic emissions of South and South-East Asia increase ozone over Tibet and the Yunnan-Guizhou Plateau by up to 5 ppb, and their contribution increases with height due to strong vertical transport. Pollution from North America and Europe mainly accompanies strong westerly winds and frequent cyclonic activities that are favorable to long-range transport. European anthropogenic pollution enhances surface ozone by 1 3 ppb over West and North China. Despite a much longer transport distance, the contribution from North America is greater than European contribution due to the nearly doubled amount of anthropogenic NMVOC emissions. The high percentage contribution of foreign anthropogenic emissions to China's ozone pollution can be partly explained by excessive domestic NOx emissions that suppress ozone production efficiency and even destroy ozone. Our study is relevant to Chinese ozone pollution control and global environmental protection collaboration.

Leopard (Panthera pardus status, distribution, and the research efforts across its range

Directory of Open Access Journals (Sweden)

Andrew P. Jacobson

2016-05-01

Full Text Available The leopard’s (Panthera pardus broad geographic range, remarkable adaptability, and secretive nature have contributed to a misconception that this species might not be severely threatened across its range. We find that not only are several subspecies and regional populations critically endangered but also the overall range loss is greater than the average for terrestrial large carnivores. To assess the leopard’s status, we compile 6,000 records at 2,500 locations from over 1,300 sources on its historic (post 1750 and current distribution. We map the species across Africa and Asia, delineating areas where the species is confirmed present, is possibly present, is possibly extinct or is almost certainly extinct. The leopard now occupies 25–37% of its historic range, but this obscures important differences between subspecies. Of the nine recognized subspecies, three (P. p. pardus, fusca, and saxicolor account for 97% of the leopard’s extant range while another three (P. p. orientalis, nimr, and japonensis have each lost as much as 98% of their historic range. Isolation, small patch sizes, and few remaining patches further threaten the six subspecies that each have less than 100,000 km2 of extant range. Approximately 17% of extant leopard range is protected, although some endangered subspecies have far less. We found that while leopard research was increasing, research effort was primarily on the subspecies with the most remaining range whereas subspecies that are most in need of urgent attention were neglected.

Extensive range overlap between heliconiine sister species: evidence for sympatric speciation in butterflies?

Science.gov (United States)

Rosser, Neil; Kozak, Krzysztof M; Phillimore, Albert B; Mallet, James

2015-06-30

Sympatric speciation is today generally viewed as plausible, and some well-supported examples exist, but its relative contribution to biodiversity remains to be established. We here quantify geographic overlap of sister species of heliconiine butterflies, and use age-range correlations and spatial simulations of the geography of speciation to infer the frequency of sympatric speciation. We also test whether shifts in mimetic wing colour pattern, host plant use and climate niche play a role in speciation, and whether such shifts are associated with sympatry. Approximately a third of all heliconiine sister species pairs exhibit near complete range overlap, and analyses of the observed patterns of range overlap suggest that sympatric speciation contributes 32%-95% of speciation events. Müllerian mimicry colour patterns and host plant choice are highly labile traits that seem to be associated with speciation, but we find no association between shifts in these traits and range overlap. In contrast, climatic niches of sister species are more conserved. Unlike birds and mammals, sister species of heliconiines are often sympatric and our inferences using the most recent comparative methods suggest that sympatric speciation is common. However, if sister species spread rapidly into sympatry (e.g. due to their similar climatic niches), then assumptions underlying our methods would be violated. Furthermore, although we find some evidence for the role of ecology in speciation, ecological shifts did not show the associations with range overlap expected under sympatric speciation. We delimit species of heliconiines in three different ways, based on "strict and " "relaxed" biological species concepts (BSC), as well as on a surrogate for the widely-used "diagnostic" version of the phylogenetic species concept (PSC). We show that one reason why more sympatric speciation is inferred in heliconiines than in birds may be due to a different culture of species delimitation in the two

Conservation Concern for the Deteriorating Geographical Range of the Grey Parrot in Cameroon

Directory of Open Access Journals (Sweden)

Simon A. Tamungang

2014-01-01

Full Text Available The need for information on Grey Parrot distribution and vegetation associations for informed management and policy decisions was the basis for this study. A nationwide survey of the Grey Parrot population and habitat status was carried out, using questionnaire and point count methods. From the results, the extent of the contemporary range of the parrots was restricted to Southern Cameroon, which harbours the rainforest. Regional parrot population means ranged from 3,487 parrots in the Littoral to 1,351,275 parrots in the East Regions. The extent of the contemporary range as a percentage of the whole country was 25.4% and as a percentage of the regions with rainforest was 44.5%. The historic range of the bird has been reduced by over 55.5%. Estimated percentage of forest lost per region ranged from 20.4% in the Centre to 57.1% in the East and South Regions. At a global level, Cameroon contributed 9% to the total extent of the range of the Grey Parrot in Africa. The range is increasingly fragmented, contracted, and lost through land-based socioeconomic activities. These degradation pressures on the range called for urgent conservation considerations for long-term survival of the parrot species and its associated biodiversity in Cameroon.

Precise Range Determination Using Laser Ranging Data of LAGEOS

Directory of Open Access Journals (Sweden)

Kwang-Ryul Kim

1993-12-01

Full Text Available Satellite laser ranging observation of LAGEOS ¥± has been performed using the SLR System at Sheshan Laser Ranging Station, Shanghai Observatory. And we obtained 1,838 observational points The observed range data is corrected by means of system delay correction using ground target observation, atmospheric refraction delay correction, offset correction, general relativistic correction and tide correction including solid tide, polar tide and ocean tide. As a result, the determined range delay mean value is 19.12m and the mean internal accuracy by means of polynomial fitting and least square method is ¡¾7cm. Corrected observational points are 1,340 and noise ratio to total observational points is 27.1%

Assessment of community noise for a medium-range airplane with open-rotor engines

Science.gov (United States)

Kopiev, V. F.; Shur, M. L.; Travin, A. K.; Belyaev, I. V.; Zamtfort, B. S.; Medvedev, Yu. V.

2017-11-01

Community noise of a hypothetical medium-range airplane equipped with open-rotor engines is assessed by numerical modeling of the aeroacoustic characteristics of an isolated open rotor with the simplest blade geometry. Various open-rotor configurations are considered at constant thrust, and the lowest-noise configuration is selected. A two-engine medium-range airplane at known thrust of bypass turbofan engines at different segments of the takeoff-landing trajectory is considered, after the replacement of those engines by the open-rotor engines. It is established that a medium-range airplane with two open-rotor engines meets the requirements of Chapter 4 of the ICAO standard with a significant margin. It is shown that airframe noise makes a significant contribution to the total noise of an airplane with open-rotor engines at landing.

Two-current nucleon observables in Skyrme model

International Nuclear Information System (INIS)

Chemtob, M.

1987-01-01

Three independent two-current nucleon observables are studied within the two-flavor Skyrme model for the πρω system. The effecive lagrangian is that of the gauged chiral symmetry approach, consistent with the vector meson dominance, in the linear realization (for the vector mesons) of the global chiral symmetry. The first application deals with the nucleon electric polarizability and magnetic susceptibility. Both seagull and dispersive contributions appear and we evaluate the latter in terms of the sums over intermediate states. The results are compared with existing quark model results as well as with empirical determinations. The second application concerns the zero-point quantum correction to the skyrmion mass. We apply a chiral perturbation theory approach to evaluate the ion loop contribution to the nucleon mass. The comparison with the conventional Skyrme model result reveals an important sensitivity to the stabilization mechanism. The third application is to lepton-nucleon deep inelastic scattering in the Bjorken scaling limit. The structure tensor is calculated in terms of the representation as a commutator product of two currents. Numerical results are presented for the scaling function F 2 (x). An essential use is made of the large N c (number of colors) approximation in all these applications. In the numerical computations we ignore the distortion effects, relative to the free plane wave limit, on the pionic fluctuations. (orig.)

Reduced pollinator service and elevated pollen limitation at the geographic range limit of an annual plant.

Science.gov (United States)

Moeller, David A; Geber, Monica A; Eckhart, Vincent M; Tiffin, Peter

2012-05-01

Mutualisms are well known to influence individual fitness and the population dynamics of partner species, but little is known about whether they influence species distributions and the location of geographic range limits. Here, we examine the contribution of plant-pollinator interactions to the geographic range limit of the California endemic plant Clarkia xantiana ssp. xantiana. We show that pollinator availability declined from the center to the margin of the geographic range consistently across four years of study. This decline in pollinator availability was caused to a greater extent by variation in the abundance of generalist rather than specialist bee pollinators. Climate data suggest that patterns of precipitation in the current and previous year drove variation in bee abundance because of its effects on cues for bee emergence in the current year and the abundance of floral resources in the previous year. Experimental floral manipulations showed that marginal populations had greater outcross pollen limitation of reproduction, in parallel with the decline in pollinator abundance. Although plants are self-compatible, we found no evidence that autonomous selfing contributes to reproduction, and thus no evidence that it alleviates outcross pollen limitation in marginal populations. Furthermore, we found no association between the distance to the range edge and selfing rate, as estimated from sequence and microsatellite variation, indicating that the mating system has not evolved in response to the pollination environment at the range periphery. Overall, our results suggest that dependence on pollinators for reproduction may be an important constraint limiting range expansion in this system.

Anaerobic digestion and digestate use: accounting of greenhouse gases and global warming contribution

DEFF Research Database (Denmark)

Møller, Jacob; Boldrin, Alessio; Christensen, Thomas Højlund

2009-01-01

measured in CO2-equivalents per tonne of wet waste. The GHG accounting was done by distinguishing between direct contributions at the AD facility and indirect upstream or downstream contributions. GHG accounting for a generic AD facility with either biogas utilization at the facility or upgrading...... highly influenced the result. In comparison with the few published GWFs for AD, the range of our data was much larger demonstrating the need to use a consistent and robust approach to GHG accounting and simultaneously accept that some key parameters are highly uncertain....

Contributions of scalar leptoquarks to the cross sections for the production of quark-antiquark pairs in electron-positron annihilation

International Nuclear Information System (INIS)

Povarov, A.V.; Smirnov, A.D.

2003-01-01

The contributions of scalar-leptoquark doublets to the cross sections σ QQ-tilde ' for the production of quark-antiquark pairs in electron-positron annihilation are calculated within the minimal model based on the four-color symmetry of quarks and leptons. These contributions are analyzed versus the scalar-leptoquark masses and the mixing parameters of the model at colliding-particle energies in the range 250-1000 GeV. It is shown that the contributions in question are of greatest importance for processes leading to t-quark production. In particular, it is found that, with allowance for the contribution of the scalar leptoquark of charge 5/3 and mass in the range 250-500 GeV, the cross section σ tt-tilde calculated at a mixing-parameter value of k t ∼ 1 may be severalfold larger than the corresponding cross section σ tt-tilde (SM) within the Standard Model. The possibility of setting constraints on the scalar-leptoquark masses and on the mixing parameters by measuring such contributions at future electron-positron colliders is indicated

Spatial Cognition and Range Use in Free-Range Laying Hens.

Science.gov (United States)

Campbell, Dana L M; Talk, Andrew C; Loh, Ziyang A; Dyall, Tim R; Lee, Caroline

2018-02-08

Radio-frequency identification tracking shows individual free-range laying hens vary in range use, with some never going outdoors. The range is typically more environmentally complex, requiring navigation to return to the indoor resources. Outdoor-preferring hens may have improved spatial abilities compared to indoor-preferring hens. Experiment 1 tested 32 adult ISA Brown hens in a T-maze learning task that showed exclusively-indoor birds were slowest to reach the learning success criterion ( p 0.05), the age that coincided with the onset of lay. Enriched birds that were faster to learn the maze task showed more range visits in the first 4 weeks of range access. Enriched and non-enriched birds showed no differences in telencephalon or hippocampal volume ( p > 0.05). Fear may reduce spatial abilities but further testing with more pen replicates per early rearing treatments would improve our understanding of the relationship between spatial cognitive abilities and range use.

Normal lactate concentration range in the neonatal brain.

Science.gov (United States)

Tomiyasu, Moyoko; Aida, Noriko; Shibasaki, Jun; Tachibana, Yasuhiko; Endo, Mamiko; Nozawa, Kumiko; Shimizu, Eiji; Tsuji, Hiroshi; Obata, Takayuki

2016-11-01

Lactate peaks are occasionally observed during in vivo magnetic resonance spectroscopy (MRS) scans of the neonatal brain, even in healthy patients. The purpose of this study was to investigate the normal range of neonatal brain lactate concentration, as a definitive normal range would be clinically valuable. Using a clinical 3T scanner (echo/repetition times, 30/5000ms), single-voxel MRS data were obtained from the basal ganglia (BG) and centrum semiovale (CS) in 48 healthy neonates (postconceptional age (PCA), 30-43weeks), nine infants (age, 1-12months old), and 20 children (age, 4-15years). Lactate concentrations were calculated using an MRS signal quantification program, LCModel. Correlations between regional lactate concentration and PCA (neonates), or age (all subjects) were investigated. Absolute lactate concentrations of the BG and CS were as follows: neonates, 0.77mM (0-2.02) [median (range)] and 0.77 (0-1.42), respectively; infants, 0.38 (0-0.79) and 0.49 (0.17-1.17); and children, 0.17 (0-0.76) and 0.22 (0-0.80). Overall, subjects' lactate concentrations decreased significantly with age (Spearman: BG, n=61, ρ=-0.38, p=0.003; CS, n=68, ρ=-0.57, p<0.001). However, during the neonatal period no correlations were detected between lactate concentration in either region and PCA. We determined normal ranges of neonatal lactate concentration, which may prove useful for diagnostic purposes. Further studies regarding changes in brain lactate concentration during development would help clarify the reasons for higher concentrations observed during the neonatal period, and contribute to improvements in diagnoses. Copyright © 2016 Elsevier Inc. All rights reserved.

Observations on discretization errors in twisted-mass lattice QCD

International Nuclear Information System (INIS)

Sharpe, Stephen R.

2005-01-01

I make a number of observations concerning discretization errors in twisted-mass lattice QCD that can be deduced by applying chiral perturbation theory including lattice artifacts. (1) The line along which the partially conserved axial current quark mass vanishes in the untwisted-mass-twisted-mass plane makes an angle to the twisted-mass axis which is a direct measure of O(a) terms in the chiral Lagrangian, and is found numerically to be large; (2) Numerical results for pionic quantities in the mass plane show the qualitative properties predicted by chiral perturbation theory, in particular, an asymmetry in slopes between positive and negative untwisted quark masses; (3) By extending the description of the 'Aoki regime' (where m q ∼a 2 Λ QCD 3 ) to next-to-leading order in chiral perturbation theory I show how the phase-transition lines and lines of maximal twist (using different definitions) extend into this region, and give predictions for the functional form of pionic quantities; (4) I argue that the recent claim that lattice artifacts at maximal twist have apparent infrared singularities in the chiral limit results from expanding about the incorrect vacuum state. Shifting to the correct vacuum (as can be done using chiral perturbation theory) the apparent singularities are summed into nonsingular, and furthermore predicted, forms. I further argue that there is no breakdown in the Symanzik expansion in powers of lattice spacing, and no barrier to simulating at maximal twist in the Aoki regime

Nuclear moments and nuclear structure. Annual progress report, August 1, 1981-August 31, 1982

International Nuclear Information System (INIS)

Madansky, L.; Lee, Y.K.

1982-01-01

This report is a review of the activities of the period from August 1, 1981 through August 31, 1982. The final analysis of pi-zero production in heavy ion collisions representing experiments at the Bevalac with a system previously described is completed. The main results involve cross sections for central collisions resulting in the production of pi-zeros, charged pions, and proton multiplicities, and some results of correlations and low energy gamma radiation. Results from the alpha-alpha experiment at the CERN ISR are included in the form of a published paper and an outline of papers that are in press. A short report of a collision effect in an anomalon experiment is included as well. The energetic particle spectra from μ - -capture in medium heavy nuclei were studied at TRIUMF, using the large scintillation counters for neutron and proton detection and multiple Ge(Li) and NaI(Tl) counters. The preliminary analysis indicates the presence of such an unusual energetic component. The measurement of the particle and γ-ray correlation in π - -capture in 165 Ho was completed during this year, and the data analysis is continuing in order to elucidate the discrete spectral features, high spin generation and other correlations. A measurement was finished in our search for a new type of strong perturbation of pionic x-ray by the use of coincidences between pionic x-rays and γ-rays from a deformed nuclei

Long range correlation in Higgs boson plus two jets production at the LHC

Energy Technology Data Exchange (ETDEWEB)

Sun, Peng [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Nuclear Science Division; Yuan, C. -P. [Michigan State Univ., East Lansing, MI (United States). Dept. of Physics and Astronomy; Yuan, Feng [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Nuclear Science Division

2016-09-09

Here, we study Higgs boson plus two high energy jets production at the LHC in the kinematics where the two jets are well separated in rapidity. The partonic processes are dominated by the t-channel weak boson fusion (WBF) and gluon fusion (GF) contributions. We derive the associated QCD resummation formalism for the correlation analysis where the total transverse momentum q⊥ of the Higgs boson and two jets is small. Because of different color structures, the resummation results lead to distinguished behaviors: the WBF contribution peaks at relative low q⊥ while all GF channel contributions are strongly de-correlated and spread to a much wider q⊥ range. Furthermore, by applying a kinematic cut on q⊥, one can effectively increase the WBF signal to the GF background by a significant factor. This, then strengthens the ability to investigate the WBF channel in Higgs boson production and study the couplings of Higgs to electroweak bosons.

Compressive laser ranging.

Science.gov (United States)

Babbitt, Wm Randall; Barber, Zeb W; Renner, Christoffer

2011-12-15

Compressive sampling has been previously proposed as a technique for sampling radar returns and determining sparse range profiles with a reduced number of measurements compared to conventional techniques. By employing modulation on both transmission and reception, compressive sensing in ranging is extended to the direct measurement of range profiles without intermediate measurement of the return waveform. This compressive ranging approach enables the use of pseudorandom binary transmit waveforms and return modulation, along with low-bandwidth optical detectors to yield high-resolution ranging information. A proof-of-concept experiment is presented. With currently available compact, off-the-shelf electronics and photonics, such as high data rate binary pattern generators and high-bandwidth digital optical modulators, compressive laser ranging can readily achieve subcentimeter resolution in a compact, lightweight package.

On the physical contributions to the third-order nonlinear optical response in plasmonic nanocomposites

International Nuclear Information System (INIS)

Fernández-Hernández, Roberto Carlos; Gleason-Villagran, Roberto; Rodríguez-Fernández, Luis; Crespo-Sosa, Alejandro; Cheang-Wong, Juan Carlos; López-Suárez, Alejandra; Oliver, Alicia; Reyes-Esqueda, Jorge Alejandro; Torres-Torres, Carlos; Rangel-Rojo, Raúl

2012-01-01

Au and Ag isotropic and anisotropic nanocomposites were prepared using the ion implantation technique. Their optical properties were studied at several wavelengths in the optical range 300–800 nm, across their plasmon resonances. The linear regime was characterized by measuring the absorption spectrum and the third-order nonlinear regime by means of the Z-scan technique using a tunable picosecond pulsed laser system (26 ps). Open-aperture Z-scan traces show a superposition of different optical nonlinear absorption (NLA) processes in the whole range studied. We associate these phenomena with the excitation of inter- and intra-band electronic transitions, which contribute with a positive sign to NLA, and to the formation of hot-electrons, which contribute with opposite sign to NLA. Closed-aperture traces for measuring nonlinear refraction (NLR) show different signs for Au and Ag samples, and a change of sign in Au is found when purely inter-band transitions are excited. In this work, for the appropriate wavelength, it is worth remarking on the free-electron response to the exciting light and its strong contribution to the nonlinear optical properties for low (intra-band) and high (hot-electrons) irradiances. (paper)

Temperature dependence of the domain wall magneto-Seebeck effect: avoiding artifacts of lead contributions

Science.gov (United States)

Fernández Scarioni, Alexander; Krzysteczko, Patryk; Sievers, Sibylle; Hu, Xiukun; Schumacher, Hans W.

2018-06-01

We study the resistive and thermopower signatures of a single domain wall in a magnetic nanowire in the temperature range from 4 K to 204 K. The results are compared to the anisotropic magnetoresistance (AMR) and anisotropic magneto-Seebeck (AMS) data of the whole permalloy nanowire. The AMS ratio of the nanowire reveals a sign change at a temperature of 98 K, while the AMR ratio is positive over the complete temperature range. This behavior is also observed for the domain wall, allowing an attribution of the measured signatures to the domain wall magneto-Seebeck and domain wall magnetoresistive contributions. However, the observed zero crossing of the AMS ratio, in both types of measurements is not expected for permalloy, since the Mott formula predicts a temperature dependency of the AMS identical to the AMR. We discuss the origin of this behavior and can attribute it to the contributions of the lead and the protective platinum layer used in our devices. A correction scheme is presented and applied. Such contributions could also play a role in the analysis of magneto-Seebeck effects in other nanoscale devices, such as the tunnel magneto-Seebeck effect of magnetic tunnel junctions.

75 FR 34388 - Employee Contribution Elections and Contribution Allocations

Science.gov (United States)

2010-06-17

... contributions equal to 3 percent of the employee's basic pay will be deducted from his or her pay and... employees who are rehired after a separation in service of 31 or more calendar days and who are eligible to participate in the TSP will automatically have 3 percent of their basic pay contributed to the TSP, unless...

Contribution of honeybee drones of different age to colonial thermoregulation.

Science.gov (United States)

Kovac, Helmut; Stabentheiner, Anton; Brodschneider, Robert

2009-01-01

In addition to honeybee workers, drones also contribute to colonial thermoregulation. We show the drones' contribution to thermoregulation at 5 different experimental temperatures ranging from 15-34 °C. The frequency and the degree of endothermy depended on the drones' local ambient temperature and age. Location on brood or non-brood areas had no influence. The frequency of endothermic drones and the intensity of endothermy increased with decreasing temperature. 30% of drones of 8 days and older heated their thorax by more than 1 °C above the abdomen. The youngest drones (0-2 days) did not exceed this level of endothermy. Though young drones were less often engaged in active heat production, their contribution to brood warming was not insignificant because their abundance on the brood nest was 3.5 times higher than that of the oldest drones (≥13 days). Results suggest that the stimulus for the drones' increased frequency of heating at low experimental temperatures was their low local ambient air and/or comb temperature.

Contribution of honeybee drones of different age to colonial thermoregulation*

Science.gov (United States)

Kovac, Helmut; Stabentheiner, Anton; Brodschneider, Robert

2011-01-01

In addition to honeybee workers, drones also contribute to colonial thermoregulation. We show the drones’ contribution to thermoregulation at 5 different experimental temperatures ranging from 15–34 °C. The frequency and the degree of endothermy depended on the drones’ local ambient temperature and age. Location on brood or non-brood areas had no influence. The frequency of endothermic drones and the intensity of endothermy increased with decreasing temperature. 30% of drones of 8 days and older heated their thorax by more than 1 °C above the abdomen. The youngest drones (0–2 days) did not exceed this level of endothermy. Though young drones were less often engaged in active heat production, their contribution to brood warming was not insignificant because their abundance on the brood nest was 3.5 times higher than that of the oldest drones (≥13 days). Results suggest that the stimulus for the drones’ increased frequency of heating at low experimental temperatures was their low local ambient air and/or comb temperature. PMID:22140282

Atmospheric concentration of 210Pb in East Asia and its contribution to Japanese islands by long-range transport

International Nuclear Information System (INIS)

Doi, Taeko; Sato, Shin; Sato, Jun

2007-01-01

Atmospheric 210 Pb is a long-lived progeny of 222 Rn generated from the earth's crust and exists as adsorbed onto the surface of aerosol particles. The distribution of atmospheric 210 Pb in East Asia reflects (1) the concentration levels in continental and maritime air masses and (2) the spatial extent of the continental air mass. This paper reviews the previously observed results on seasonal variation of 210 Pb concentration at several sites of Japan, Korea and China to evaluate the contribution of continental to Japanese atmosphere, and the specific activity of 210 Pb in the main components of aerosol samples and discusses from the view point of the Japanese islands. The authors conclude that aerosols from continental East Asia in winter contain more soil particles with low specific radioactivity of 210 Pb than the aerosols in Japan and that the natural radionuclide is extremely useful tracer for researches on meteorological phenomena and global transfer of environmental pollution. (S. Ohno)

Analysis of the TMI-2 source range detector response

International Nuclear Information System (INIS)

Carew, J.F.; Diamond, D.J.; Eridon, J.M.

1980-01-01

In the first few hours following the TMI-2 accident large variations (factors of 10-100) in the source range (SR) detector response were observed. The purpose of this analysis was to quantify the various effects which could contribute to these large variations. The effects evaluated included the transmission of neutrons and photons from the core to detector and the reduction in the multiplication of the Am-Be startup sources, and subsequent reduction in SR detector response, due to core voiding. A one-dimensional ANISN slab model of the TMI-2 core, core externals, pressure vessel and containment has been constructed for calculation of the SR detector response and is presented

Dietary arsenic exposure in Brazil: The contribution of rice and beans.

Science.gov (United States)

Ciminelli, Virginia S T; Gasparon, Massimo; Ng, Jack C; Silva, Gabriela C; Caldeira, Claudia L

2017-02-01

The human health risk associated with arsenic in food in Southeast Brazil was quantified. Based on the most commonly consumed food types in the Brazilian diet, the maximum inorganic As (iAs) daily intake from food (0.255 μg kg -1 body weight per day) is approximately 9% of the Benchmark Dose Lower Limit (BMDL 0.5 ) of 3 μg kg -1 body weight per day set by the World Health Organization (WHO) and Food and Agriculture Organization (FAO) Joint Expert Committee in Food Additives (JECFA). When water is included, the contribution of food to the total intake varies from 96.9% to 39.7%. Rice and beans, the main Brazilian staple food, contribute between 67 and 90% of the total As intake from food (46-79% from rice and 11-23% from beans). The substantial contribution of beans to total As food intake is reported for the first time. The broad range of As concentrations in rice and beans highlights the variable and potentially large contribution of both to As food intake in places where diet consists largely of these two food categories. Copyright © 2016 Elsevier Ltd. All rights reserved.

Dislocation mechanisms for plastic flow of nickel in the temperature range 4.2-1200K

International Nuclear Information System (INIS)

Sastry, D.H.; Tangri, K.

1975-01-01

The temperature ranges of thermal and athermal deformation behaviour of nickel are identified by employing the temperature-dependence of flow-stress and strain-rate cycling data. The results are used to present a unified view of dislocation mechanisms of glide encompassing the two thermally activated and the intermediate athermal regimes of plastic flow. In the low-temperature thermally activated region (<250K) the strain rate is found to be controlled by the repulsive intersection of glide and forest dislocations, in accordance with current ideas. The athermal stress in this region can be attributed mainly to the presence of strong attractive junctions which are overcome by means of Orowan bowing, a small contribution also coming from the elastic interactions between dislocations. The values of activation area and activation energy obtained in the high-temperature region (<750K) negate the operation of a diffusion-controlled mechanism. Instead, the data support a thermal activation model involving unzipping of the attractive junctions. The internal (long-range) stress contribution here results solely from the elastic interactions between dislocations. This view concerning the high-temperature plastic flow is further supported by the observation that the Cottrell-Stokes law is obeyed over large strains in the range 750-1200K. (author)

Range-based volatility, expected stock returns, and the low volatility anomaly

Science.gov (United States)

2017-01-01

One of the foundations of financial economics is the idea that rational investors will discount stocks with more risk (volatility), which will result in a positive relation between risk and future returns. However, the empirical evidence is mixed when determining how volatility is related to future returns. In this paper, we examine this relation using a range-based measure of volatility, which is shown to be theoretically, numerically, and empirically superior to other measures of volatility. In a variety of tests, we find that range-based volatility is negatively associated with expected stock returns. These results are robust to time-series multifactor models as well as cross-sectional tests. Our findings contribute to the debate about the direction of the relationship between risk and return and confirm the presence of the low volatility anomaly, or the anomalous finding that low volatility stocks outperform high volatility stocks. In other tests, we find that the lower returns associated with range-based volatility are driven by stocks with lottery-like characteristics. PMID:29190652

Range-based volatility, expected stock returns, and the low volatility anomaly.

Science.gov (United States)

Blau, Benjamin M; Whitby, Ryan J

2017-01-01

One of the foundations of financial economics is the idea that rational investors will discount stocks with more risk (volatility), which will result in a positive relation between risk and future returns. However, the empirical evidence is mixed when determining how volatility is related to future returns. In this paper, we examine this relation using a range-based measure of volatility, which is shown to be theoretically, numerically, and empirically superior to other measures of volatility. In a variety of tests, we find that range-based volatility is negatively associated with expected stock returns. These results are robust to time-series multifactor models as well as cross-sectional tests. Our findings contribute to the debate about the direction of the relationship between risk and return and confirm the presence of the low volatility anomaly, or the anomalous finding that low volatility stocks outperform high volatility stocks. In other tests, we find that the lower returns associated with range-based volatility are driven by stocks with lottery-like characteristics.

Range-based volatility, expected stock returns, and the low volatility anomaly.

Directory of Open Access Journals (Sweden)

Benjamin M Blau

Full Text Available One of the foundations of financial economics is the idea that rational investors will discount stocks with more risk (volatility, which will result in a positive relation between risk and future returns. However, the empirical evidence is mixed when determining how volatility is related to future returns. In this paper, we examine this relation using a range-based measure of volatility, which is shown to be theoretically, numerically, and empirically superior to other measures of volatility. In a variety of tests, we find that range-based volatility is negatively associated with expected stock returns. These results are robust to time-series multifactor models as well as cross-sectional tests. Our findings contribute to the debate about the direction of the relationship between risk and return and confirm the presence of the low volatility anomaly, or the anomalous finding that low volatility stocks outperform high volatility stocks. In other tests, we find that the lower returns associated with range-based volatility are driven by stocks with lottery-like characteristics.

Theoretical research in intermediate-energy nuclear physics

International Nuclear Information System (INIS)

Seki, R.

1991-01-01

This report discusses progress that has been made on the following six problems: (1) final state interactions in (e,e'p) at high momentum transfer; (2) a numerical calculation of skyrmion-antiskyrmion annihilation; (3) pion-nucleus interactions above 0.5 GeV/c; (4) pionic atom anomaly; (5) baryon interactions in Skyrme model; and (6) large N c quantum hydrodynamics. The problems deal with various topics in intermediate-energy nuclear physics. Since we plan to continue the investigation of these problems in the third year, we describe the plan of the investigation together

Pions in the nuclear medium

International Nuclear Information System (INIS)

Chanfray, G.

1996-07-01

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

πd scattering lengths taking into account the pion and nucleon mass differences

International Nuclear Information System (INIS)

Pupyshev, V.V.; Rakityanskii, S.A.

1985-01-01

The scattering lengths and s-wave phase shifts for πd elastic scattering are calculated in the framework of an isotopically noninvariant approach that takes into account the mass splitting of the pionic and nucleonic isomultiplets. It is shown that the particle mass differences lead to appearance of the imaginary parts in the πd scattering lengths (approx.10 -4 fm) not associated with pion absorption. The sensitivity of the mass-difference effects to variation of the parameters of the πN potential is studied and turns out to be small

Hadronic atoms and leptonic conservations: Final technical report, February 1, 1984-January 31, 1987

International Nuclear Information System (INIS)

Kunselman, R.

1987-01-01

X rays from pionic atoms were studied to determine nuclear distributions, to determine pion-nuclear interaction parameters, and to test energy calculations; x rays from sigmonic and kaonic atoms were studied to determine the sigma-minus magnetic moment, as well as to determine sigma-nuclear interaction parameters, and to determine the sigma-minus and kaon mass. A search for the rare decay μ + → e + γ at a sensitivity less than 10 -13 is being constructed. A more sensitive search was begun for muonium conversion μ + e - → μ - e + . 6 refs

Measurement of the vector np → dπ{sup 0}π{sup 0} reaction with polarized beam in the region of the d*(2380) resonance

Energy Technology Data Exchange (ETDEWEB)

Adlarson, P.; Calen, H.; Fransson, K.; Gullstroem, C.O.; Heijkenskjoeld, L.; Johansson, T.; Marciniewski, P.; Wolke, M.; Zlomanczuk, J. [Uppsala University, Division of Nuclear Physics, Department of Physics and Astronomy, Box 516, Uppsala (Sweden); Augustyniak, W.; Marianski, B.; Morsch, H.P.; Trzcinski, A.; Zupranski, P. [National Centre for Nuclear Research, Department of Nuclear Physics, Warsaw (Poland); Bardan, W.; Ciepal, I.; Czerwinski, E.; Jarczyk, L.; Kamys, B.; Khatri, G.; Kistryn, S.; Krzemien, W.; Magiera, A.; Moskal, P.; Rudy, Z.; Rundel, O.; Schaetti-Ozerianska, I.; Skurzok, M.; Smyrski, J.; Wronska, A.; Zielinski, M.J. [Jagiellonian University, Institute of Physics, Krakow (Poland); Bashkanov, M. [University of Edinburgh, James Clerk Maxwell Building, School of Physics and Astronomy, Edinburgh (United Kingdom); Eberhard-Karls-Universitaet Tuebingen, Physikalisches Institut, Tuebingen (Germany); Bergmann, F.S.; Demmich, K.; Huesken, N.; Khoukaz, A.; Sitterberg, K.; Taeschner, A. [Westfaelische Wilhelms-Universitaet Muenster, Institut fuer Kernphysik, Muenster (Germany); Berlowski, M.; Stepaniak, J. [National Centre for Nuclear Research, High Energy Physics Department, Warsaw (Poland); Bhatt, H.; Varma, R. [Indian Institute of Technology Bombay, Department of Physics, Powai, Maharashtra (India); Bondar, A.; Kuzmin, A.; Shwartz, B. [Budker Institute of Nuclear Physics of SB RAS, Novosibirsk (Russian Federation); Novosibirsk State University, Novosibirsk (Russian Federation); Buescher, M.; Engels, R.; Goldenbaum, F.; Hejny, V.; Khan, F.A.; Lersch, D.; Lorentz, B.; Ohm, H.; Prasuhn, D.; Schadmand, S.; Sefzick, T.; Serdyuk, V.; Stassen, R.; Sterzenbach, G.; Stockhorst, H.; Zurek, M. [Forschungszentrum Juelich, Institut fuer Kernphysik, Juelich (Germany); Clement, H. [Eberhard-Karls-Universitaet Tuebingen, Physikalisches Institut, Tuebingen (Germany); University of Tuebingen, Kepler Center for Astro- and Particle Physics, Tuebingen (Germany); Erven, A.; Erven, W.; Kemmerling, G.; Kleines, H.; Wuestner, P. [Forschungszentrum Juelich, Zentralinstitut fuer Engineering, Elektronik und Analytik, Juelich (Germany); Eyrich, W.; Zink, A. [Friedrich-Alexander-Universitaet Erlangen-Nuernberg, Physikalisches Institut, Erlangen (Germany); Fedorets, P. [Forschungszentrum Juelich, Institut fuer Kernphysik, Juelich (Germany); State Scientific Center of the Russian Federation, Institute for Theoretical and Experimental Physics, Moscow (Russian Federation); Foehl, K. [Justus-Liebig-Universitaet Giessen, II. Physikalisches Institut, Giessen (Germany); Goswami, A.; Roy, A. [Indian Institute of Technology Indore, Department of Physics, Indore, Madhya Pradesh (India); Grigoryev, K. [Forschungszentrum Juelich, Institut fuer Kernphysik, Juelich (Germany); Petersburg Nuclear Physics Institute, High Energy Physics Division, Gatchina, Leningrad district (Russian Federation); Kirillov, D.A.; Piskunov, N.M. [Joint Institute for Nuclear Physics, Veksler and Baldin Laboratory of High Energiy Physics, Dubna, Moscow region (Russian Federation); Klos, B.; Stephan, E. [University of Silesia, August Chelkowski Institute of Physics, Katowice (Poland); Kulessa, P.; Pysz, K.; Siudak, R.; Szczurek, A. [Polish Academy of Sciences, The Henryk Niewodniczanski Institute of Nuclear Physics, Krakow (Poland); Kupsc, A.; Pszczel, D. [Uppsala University, Division of Nuclear Physics, Department of Physics and Astronomy, Box 516, Uppsala (Sweden); National Centre for Nuclear Research, High Energy Physics Department, Warsaw (Poland); Lalwani, K. [Malaviya National Institute of Technology Jaipur, JLN Marg, Department of Physics, Jaipur, Rajasthan (India); Maier, R.; Stroeher, H. [Forschungszentrum Juelich, Institut fuer Kernphysik, Juelich (Germany); Forschungszentrum Juelich, JARA-FAME, Juelich Aachen Research Alliance, Juelich (Germany); RWTH Aachen, Aachen (Germany); Perez del Rio, E. [Eberhard-Karls-Universitaet Tuebingen, Physikalisches Institut, Tuebingen (Germany); Pyszniak, A. [Uppsala University, Division of Nuclear Physics, Department of Physics and Astronomy, Box 516, Uppsala (Sweden); Jagiellonian University, Institute of Physics, Krakow (PL); Ritman, J. [Forschungszentrum Juelich, Institut fuer Kernphysik, Juelich (DE); Forschungszentrum Juelich, JARA-FAME, Juelich Aachen Research Alliance, Juelich (DE); RWTH Aachen, Aachen (DE); Ruhr-Universitaet Bochum, Institut fuer Experimentalphysik I, Bochum (DE); Sawant, S. [Indian Institute of Technology Bombay, Department of Physics, Powai, Maharashtra (IN); Forschungszentrum Juelich, Institut fuer Kernphysik, Juelich (DE); Skorodko, T. [Eberhard-Karls-Universitaet Tuebingen, Physikalisches Institut, Tuebingen (DE); University of Tuebingen, Kepler Center for Astro- and Particle Physics, Tuebingen (DE); Tomsk State University, Department of Physics, Tomsk (RU); Sopov, V. [State Scientific Center of the Russian Federation, Institute for Theoretical and Experimental Physics, Moscow (RU); Yamamoto, A. [High Energy Accelerator Research Organisation KEK, Tsukuba, Ibaraki (JP); Zabierowski, J. [National Centre for Nuclear Research, Department of Astrophysics, Lodz (PL); Collaboration: WASA-at-COSY Collaboration

2016-05-15

We report on a high-statistics measurement of the most basic double-pionic fusion reaction vector np→dπ{sup 0}π{sup 0} over the energy region of the d*(2380) resonance by use of a polarized deuteron beam and observing the double fusion reaction in the quasifree scattering mode. The measurements were performed with the WASA detector setup at COSY. The data reveal substantial analyzing powers and confirm conclusions about the d* resonance obtained from unpolarized measurements. We also confirm the previous unpolarized data obtained under complementary kinematic conditions. (orig.)

Linear response in the nonequilibrium zero range process

International Nuclear Information System (INIS)

Maes, Christian; Salazar, Alberto

2014-01-01

We explore a number of explicit response formulæ around the boundary driven zero range process to changes in the exit and entrance rates. In such a nonequilibrium regime kinetic (and not only thermodynamic) aspects make a difference in the response. Apart from a number of formal approaches, we illustrate a general decomposition of the linear response into entropic and frenetic contributions, the latter being realized from changes in the dynamical activity at the boundaries. In particular in this way one obtains nonlinear modifications to the Green–Kubo relation. We end by bringing some general remarks about the situation where that nonequilibrium response remains given by the (equilibrium) Kubo formula such as for the density profile in the boundary driven Lorentz gas

A methodology for direct quantification of over-ranging length in helical computed tomography with real-time dosimetry.

Science.gov (United States)

Tien, Christopher J; Winslow, James F; Hintenlang, David E

2011-01-31

In helical computed tomography (CT), reconstruction information from volumes adjacent to the clinical volume of interest (VOI) is required for proper reconstruction. Previous studies have relied upon either operator console readings or indirect extrapolation of measurements in order to determine the over-ranging length of a scan. This paper presents a methodology for the direct quantification of over-ranging dose contributions using real-time dosimetry. A Siemens SOMATOM Sensation 16 multislice helical CT scanner is used with a novel real-time "point" fiber-optic dosimeter system with 10 ms temporal resolution to measure over-ranging length, which is also expressed in dose-length-product (DLP). Film was used to benchmark the exact length of over-ranging. Over-ranging length varied from 4.38 cm at pitch of 0.5 to 6.72 cm at a pitch of 1.5, which corresponds to DLP of 131 to 202 mGy-cm. The dose-extrapolation method of Van der Molen et al. yielded results within 3%, while the console reading method of Tzedakis et al. yielded consistently larger over-ranging lengths. From film measurements, it was determined that Tzedakis et al. overestimated over-ranging lengths by one-half of beam collimation width. Over-ranging length measured as a function of reconstruction slice thicknesses produced two linear regions similar to previous publications. Over-ranging is quantified with both absolute length and DLP, which contributes about 60 mGy-cm or about 10% of DLP for a routine abdominal scan. This paper presents a direct physical measurement of over-ranging length within 10% of previous methodologies. Current uncertainties are less than 1%, in comparison with 5% in other methodologies. Clinical implantation can be increased by using only one dosimeter if codependence with console readings is acceptable, with an uncertainty of 1.1% This methodology will be applied to different vendors, models, and postprocessing methods--which have been shown to produce over-ranging lengths

Unitarity corrections to short-range order long-range rapidity correlations

CERN Document Server

Capella, A

1978-01-01

Although the effective hadronic forces have short range in rapidity space, one nevertheless expects long-range dynamical correlations induced by unitarity constraints. This paper contains a thorough discussion of long-range rapidity correlations in high-multiplicity events. In particular, the authors analyze in detail the forward- backward multiplicity correlations, measured recently in the whole CERN ISR energy range. They find from these data that the normalized variance of the number n of exchanged cut Pomerons, ((n/(n)-1)/sup 2/) , is most probably in the range 0.32 to 0.36. They show that such a number is obtained from Reggeon theory in the eikonal approximation. The authors also predict a very specific violation of local compensation of charge in multiparticle events: The violation should appear in the fourth-order zone correlation function and is absent in the second-order correlation function, the only one measured until now. (48 refs).

Does this range suit me? Range satisfaction of battery electric vehicle users.

Science.gov (United States)

Franke, Thomas; Günther, Madlen; Trantow, Maria; Krems, Josef F

2017-11-01

User satisfaction is a vital design criterion for sustainable systems. The present research aimed to understand factors relating to individually perceived range satisfaction of battery electric vehicle (BEV) users. Data from a large-scale BEV field trial (N = 72) were analyzed. Apart from an initial drop in range satisfaction, increasing practical experience was related to increased range satisfaction. Classical indicators of users' mobility profiles (daily travel distances) were only weakly related to lower range satisfaction (not significant), after controlling for practical experience and preferred coverage of mobility needs. The regularity/predictability of users' mobility patterns, the percentage of journeys not coverable because of range issues, and users' individual comfortable range accounted for variance in range satisfaction. Finally, range satisfaction was related to key indicators of general BEV acceptance (e.g., purchase intentions). These results underline the complex dynamics involved in individual range satisfaction, as well as its central role for BEV acceptance. Copyright © 2017 Elsevier Ltd. All rights reserved.

Probing General Relativity and New Physics with Lunar Laser Ranging

Energy Technology Data Exchange (ETDEWEB)

Dell' Agnello, S. [Laboratori Nazionali di Frascati (LNF) dell' INFN, Frascati, Rome (Italy); Maiello, M., E-mail: mauro.maiello@lnf.infn.it [Laboratori Nazionali di Frascati (LNF) dell' INFN, Frascati, Rome (Italy); Currie, D.G. [University of Maryland (UMD), College Park, MD (United States); Boni, A.; Berardi, S.; Cantone, C.; Delle Monache, G.O.; Intaglietta, N.; Lops, C.; Garattini, M.; Martini, M.; Patrizi, G.; Porcelli, L.; Tibuzzi, M. [Laboratori Nazionali di Frascati (LNF) dell' INFN, Frascati, Rome (Italy); Vittori, R. [Aeronautica Militare Italiana (AMI), Rome (Italy); Agenzia Spaziale Italiana (ASI), Rome (Italy); Bianco, G. [ASI-Centro di Geodesia Spaziale, Matera (Italy); Coradini, A. [INAF-Istituto di Fisica dello Spazio Interplanetario (IFSI), Via Fosso del Cavaliere 100, 00133 Rome (Italy); Dionisio, C. [Rheinmetall Italia S.p.A., Via Affile 102, 00131 Rome (Italy); March, R. [INFN-LNF and CNR-Istituto per le Applicazioni del Calcolo (IAC), Viale del Policlinico 137, 00161 Rome (Italy); Bellettini, G. [INFN-LNF and Department of Mathematics, University of Rome ' Tor Vergata' , Via della Ricerca Scientifica, 00133 Rome (Italy); and others

2012-11-11

Over the past 40 years, Lunar Laser Ranging (LLR, developed by the Univ. of Maryland (PI) and INFN-LNF (Co-PI)) to the Apollo Cube Corner Retroreflector (CCR) arrays have supplied almost all the significant tests of General Relativity (Currie et al., 2009 [12]). LLR can evaluate the PPN (Post Newtonian Parameters), addressing this way both the possible changes in the gravitational constant and the self-energy properties of the gravitational field. In addition, the LLR has provided significant information on the composition and origin of the Moon. This is the only Apollo experiment that is still in operation. Initially the Apollo LLR arrays contributed a negligible fraction of the ranging error budget. Over the decades, the ranging capabilities of the ground stations have improved by more than two orders of magnitude. Now, because of the lunar librations, the existing Apollo retroreflector arrays contribute a significant fraction of the limiting errors in the range measurements. We built a new experimental apparatus (the 'Satellite/Lunar Laser Ranging Characterization Facility', SCF) and created a new test procedure (the SCF-Test) to characterize and model the detailed thermal behavior and the optical performance of cube corner laser retroreflectors in space for industrial and scientific applications (Dell'Agnello et al., 2011 [13]). Our key experimental innovation is the concurrent measurement and modeling of the optical Far Field Diffraction Pattern (FFDP) and the temperature distribution of the SLR retroreflector payload under thermal conditions produced with a close-match solar simulator. The apparatus includes infrared cameras for non-invasive thermometry, thermal control and real-time movement of the payload to experimentally simulate satellite orientation on orbit with respect to both solar illumination and laser interrogation beams. These unique capabilities provide experimental validation of the space segment for SLR and Lunar Laser Ranging

A single particle energies

Energy Technology Data Exchange (ETDEWEB)

Bodmer, A.R. [Illinois Univ., Chicago, IL (United States). Dept. of Physics]|[Argonne National Lab., IL (United States); Usmani, Q.N.; Sami, M. [Jamia Millia Islamia, New Delhi (India). Dept. of Physics

1993-09-01

We consider the binding energies of {Lambda} hypernuclei (HN), in particular the single-particle (s.p.) energy data, which have been obtained for a wide range of HN with mass numbers A {le} 89 and for orbital angular momenta {ell}{sub {Lambda}} {le} 4. We briefly review some of the relevant properties of A hypernuclei. These are nuclei {sub {Lambda}}{sup A}Z with baryon number A in which a single {Lambda} hyperon (baryon number = 1) is bound to an ordinary nucleus {sup A}Z consisting of A - 1 nucleons = Z protons + N neutrons. The {Lambda} hyperon is neutral, has spin 1/2, strangeness S = {minus}1, isospin I = O and a mass M{sub {Lambda}} = 1116 MeV/c{sup 2}. Although the {Lambda} interacts with a nucleon, its interaction is only about half as strong as that between two nucleons, and thus very roughly V{sub {Lambda}N} {approx} 0.5 V{sub NN}. As a result, the two-body {Lambda}N system is unbound, and the lightest bound HN is the three-body hypertriton {sub {Lambda}}{sup 3}H in which the {Lambda} is bound to a deuteron with the {Lambda}-d separation energy being only {approx} 0.1 MeV corresponding to an exponential tail of radius {approx} 15 fm! In strong interactions the strangeness S is of course conserved, and the {Lambda} is distinct from the nucleons. In a HN strangeness changes only in the weak decays of the {Lambda} which can decay either via ``free`` pionic decay {Lambda} {yields} N + {pi} or via induced decay {Lambda} + N {yields} N + N which is only possible in the presence of nucleons. Because of the small energy release the pionic decay is strongly suppressed in all but the lightest HN and the induced decay dominates. However, the weak decay lifetime {approx} 10{sup {minus}10}s is in fact close to the lifetime of a free {Lambda}. Since this is much longer than the strong interaction time {approx} 10{sup {minus}22}s we can ignore the weak interactions when considering the binding of HN, just as for ordinary nuclei.

Contribution to interplay between a delamination test and a sensory analysis of mid-range lipsticks.

Science.gov (United States)

Richard, C; Tillé-Salmon, B; Mofid, Y

2016-02-01

Lipstick is currently one of the most sold products of cosmetics industry, and the competition between the various manufacturers is significant. Customers mainly seek products with high spreadability, especially long-lasting or long wear on the lips. Evaluation tests of cosmetics are usually performed by sensory analysis. This can then represent a considerable cost. The object of this study was to develop a fast and simple test of delamination (objective method with calibrated instruments) and to interplay the obtained results with those of a discriminative sensory analysis (subjective method) in order to show the relevance of the instrumental test. Three mid-range lipsticks were randomly chosen and were tested. They were made of compositions as described by the International Nomenclature of Cosmetic Ingredients (INCI). Instrumental characterization was performed by texture profile analysis and by a special delamination test. The sensory analysis was voluntarily conducted with an untrained panel as blind test to confirm or reverse the possible interplay. The two approaches or methods gave the same type of classification. The high-fat lipstick had the worst behaviour with the delamination test and the worst notation of the intensity of descriptors with the sensory analysis. There is a high correlation between the sensory analysis and the instrumental measurements in this study. The delamination test carried out should permit to quickly determine the lasting (screening test) and in consequence optimize the basic formula of lipsticks. © 2015 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

New test of the equivalence principle from lunar laser ranging

Science.gov (United States)

Williams, J. G.; Dicke, R. H.; Bender, P. L.; Alley, C. O.; Currie, D. G.; Carter, W. E.; Eckhardt, D. H.

1976-01-01

An analysis of six years of lunar-laser-ranging data gives a zero amplitude for the Nordtvedt term in the earth-moon distance yielding the Nordtvedt parameter eta = 0.00 plus or minus 0.03. Thus, earth's gravitational self-energy contributes equally, plus or minus 3%, to its inertial mass and passive gravitational mass. At the 70% confidence level this result is only consistent with the Brans-Dicke theory for omega greater than 29. We obtain the absolute value of beta - 1 less than about 0.02 to 0.05 for five-parameter parametrized post-Newtonian theories of gravitation with energy-momentum conservation.

A better understanding of long-range temporal dependence of traffic flow time series

Science.gov (United States)

Feng, Shuo; Wang, Xingmin; Sun, Haowei; Zhang, Yi; Li, Li

2018-02-01

Long-range temporal dependence is an important research perspective for modelling of traffic flow time series. Various methods have been proposed to depict the long-range temporal dependence, including autocorrelation function analysis, spectral analysis and fractal analysis. However, few researches have studied the daily temporal dependence (i.e. the similarity between different daily traffic flow time series), which can help us better understand the long-range temporal dependence, such as the origin of crossover phenomenon. Moreover, considering both types of dependence contributes to establishing more accurate model and depicting the properties of traffic flow time series. In this paper, we study the properties of daily temporal dependence by simple average method and Principal Component Analysis (PCA) based method. Meanwhile, we also study the long-range temporal dependence by Detrended Fluctuation Analysis (DFA) and Multifractal Detrended Fluctuation Analysis (MFDFA). The results show that both the daily and long-range temporal dependence exert considerable influence on the traffic flow series. The DFA results reveal that the daily temporal dependence creates crossover phenomenon when estimating the Hurst exponent which depicts the long-range temporal dependence. Furthermore, through the comparison of the DFA test, PCA-based method turns out to be a better method to extract the daily temporal dependence especially when the difference between days is significant.

Stable isotopes as a tool to differentiate eggs laid by caged, barn, free range, and organic hens.

Science.gov (United States)

Rogers, Karyne M

2009-05-27

Stable carbon and nitrogen isotope values of whole yolk, delipidized yolk, albumen, and egg membrane were analyzed from 18 different brands of chicken eggs laid under caged, barn, free range, and organic farming regimes. In general, free range and organic egg components showed enrichment of (15)N values up to 4‰ relative to caged and barn laid eggs, suggesting a higher animal protein (trophic) contribution to the chicken's diet than pure plant-based foods and/or that the feed was organically manufactured. One sample of free range and two samples of organic eggs had δ(15)N values within the range of caged or barn laid eggs, suggesting either that these eggs were mislabeled (the hens were raised under "battery" or "barn" conditions, and not permitted to forage outside) or that there was insufficient animal protein gained by foraging to shift the δ(15)N values of their primary food source. δ(13)C values of potential food sources are discussed with respect to dietary intake and contribution to the isotopic signature of the eggs to determine mixing of C(3) and C(4) diets, although they did not elucidate laying regimen. The study finds that stable nitrogen isotope analysis of egg components is potentially a useful technique to unravel dietary differences between caged or barn hens and free range hens (both conventional and organic) and could be further developed as an authentication tool in the egg industry.

The Global Contribution of Secondary Craters on the Icy Satellites

Science.gov (United States)

Hoogenboom, T.; Johnson, K. E.; Schenk, P.

2014-12-01

At present, surface ages of bodies in the Outer Solar System are determined only from crater size-frequency distributions (a method dependent on an understanding of the projectile populations responsible for impact craters in these planetary systems). To derive accurate ages using impact craters, the impactor population must be understood. Impact craters in the Outer Solar System can be primary, secondary or sesquinary. The contribution of secondary craters to the overall population has recently become a "topic of interest." Our objective is to better understand the contribution of dispersed secondary craters to the small crater populations, and ultimately that of small comets to the projectile flux on icy satellites in general. We measure the diameters of obvious secondary craters (determined by e.g. irregular crater shape, small size, clustering) formed by all primary craters on Ganymede for which we have sufficiently high resolution data to map secondary craters. Primary craters mapped range from approximately 40 km to 210 km. Image resolution ranges from 45 to 440 m/pixel. Bright terrain on Ganymede is our primary focus. These resurfaced terrains have relatively low crater densities and serve as a basis for characterizing secondary populations as a function of primary size on an icy body for the first time. Although focusing on Ganymede, we also investigate secondary crater size, frequency, distribution, and formation, as well as secondary crater chain formation on icy satellites throughout the Saturnian and Jovian systems principally Rhea. We compare our results to similar studies of secondary cratering on the Moon and Mercury. Using Galileo and Voyager data, we have identified approximately 3,400 secondary craters on Ganymede. In some cases, we measured crater density as a function of distance from a primary crater. Because of the limitations of the Galileo data, it is necessary to extrapolate from small data sets to the global population of secondary craters

Relationships between Paraspinal Muscle Activity and Lumbar Inter-Vertebral Range of Motion

OpenAIRE

du Rose, Alister; Breen, Alan

2016-01-01

Abstract: Control of the lumbar spine requires contributions from both the active and passive sub-systems. Identifying interactions between these systems may provide insight into the mechanisms of low back pain. However, as a first step it is important to investigate what is normal. The purpose of this study was to explore the relationships between the lumbar inter-vertebral range of motion and paraspinal muscle activity during weight-bearing flexion in healthy controls using quantitative flu...

Short- and long-range polar order contributions to the Ferroelectric phase of Ca.sup.2+./sup. doped SrTiO.sub.3./sub.

Czech Academy of Sciences Publication Activity Database

Markovin, P.A.; Trepakov, Vladimír; Guzhva, M.E.; Razdobarin, A.G.; Tagantsev, A. K.; Andreev, D. A.; Dejneka, Alexandr

2016-01-01

Roč. 3, č. 11 (2016), s. 1-12, č. článku 115705. ISSN 2053-1591 R&D Projects: GA ČR GA15-13778S Institutional support: RVO:68378271 Keywords : quantum paraelectrics * impurities and defects * low-temperature polar state * ferroelectric phase * long-range order * short-range Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.068, year: 2016

Sensitivity analysis using contribution to sample variance plot: Application to a water hammer model

International Nuclear Information System (INIS)

Tarantola, S.; Kopustinskas, V.; Bolado-Lavin, R.; Kaliatka, A.; Ušpuras, E.; Vaišnoras, M.

2012-01-01

This paper presents “contribution to sample variance plot”, a natural extension of the “contribution to the sample mean plot”, which is a graphical tool for global sensitivity analysis originally proposed by Sinclair. These graphical tools have a great potential to display graphically sensitivity information given a generic input sample and its related model realizations. The contribution to the sample variance can be obtained at no extra computational cost, i.e. from the same points used for deriving the contribution to the sample mean and/or scatter-plots. The proposed approach effectively instructs the analyst on how to achieve a targeted reduction of the variance, by operating on the extremes of the input parameters' ranges. The approach is tested against a known benchmark for sensitivity studies, the Ishigami test function, and a numerical model simulating the behaviour of a water hammer effect in a piping system.

Percentage-based Author Contribution Index: a universal measure of author contribution to scientific articles.

Science.gov (United States)

Boyer, Stéphane; Ikeda, Takayoshi; Lefort, Marie-Caroline; Malumbres-Olarte, Jagoba; Schmidt, Jason M

2017-01-01

Deciphering the amount of work provided by different co-authors of a scientific paper has been a recurrent problem in science. Despite the myriad of metrics available, the scientific community still largely relies on the position in the list of authors to evaluate contributions, a metric that attributes subjective and unfounded credit to co-authors. We propose an easy to apply, universally comparable and fair metric to measure and report co-authors contribution in the scientific literature. The proposed Author Contribution Index (ACI) is based on contribution percentages provided by the authors, preferably at the time of submission. Researchers can use ACI to compare the contributions of different authors, describe the contribution profile of a particular researcher or analyse how contribution changes through time. We provide such an analysis based on contribution percentages provided by 97 scientists from the field of ecology who voluntarily responded to an online anonymous survey. ACI is simple to understand and to implement because it is based solely on percentage contributions and the number of co-authors. It provides a continuous score that reflects the contribution of one author as compared to the average contribution of all other authors. For example, ACI(i) = 3, means that author i contributed three times more than what the other authors contributed on average. Our analysis comprised 836 papers published in 2014-2016 and revealed patterns of ACI values that relate to career advancement. There are many examples of author contribution indices that have been proposed but none has really been adopted by scientific journals. Many of the proposed solutions are either too complicated, not accurate enough or not comparable across articles, authors and disciplines. The author contribution index presented here addresses these three major issues and has the potential to contribute to more transparency in the science literature. If adopted by scientific journals, it

Contribution of population growth to per capita income and sectoral output growth in Japan, 1880-1970.

Science.gov (United States)

Yamaguchi, M; Kennedy, G

1984-09-01

The authors measured the positive and negative contributions of population and labor force growth to the growth of per capita income and sectoral output in Japan in the 1880-1970 period. A 2-sector growth accounting model that treats population and labor growth as separate variables was used. 3 alternative methods were used: the Residual method, the Verdoorn method, and the factor augmenting rate method. The total contribution of population cum labor growth to per capita income growth tended to be negative in the 1880-1930 period and positive in the 1930-40 and 1950-70. Over the 1880-1970 period as a whole, population cum labor growth made a positive contribution to per capita income growth under the Residual method (0.35%/year), the factor augmenting rate method (0.29%/year), and the Verdoorn method (0.01%/year). In addition, population cum labor growth contributed positively to sectoral output growth. The average contribution to agricultural output growth ranged from 1.03% (Verdoorn) - 1.46%/year (factor augmenting rate), while the average contribution to nonagricultural output growth ranged from 1.22% (Verdoorn) - 1.60%/year (Residual). Although these results are dependent on the model used, the fact that all 3 methods yielded consistent results suggests that population cum labor growth did make a positive contribution to per capita income and sectoral output growth in Japan. These findings imply that in economies where the rate of technical change in agricultural and nonagricultural sectors exceeds population growth, policies that reduce agricultural elasticities may be preferable; on the other hand, policies that reduce agricultural elasticities are to be avoided in economies with low rates of technical change. Moreover, in the early stages of economic development, policies that increase agricultural income and price elasticities should be considered.

Social Contributions in Romania

Directory of Open Access Journals (Sweden)

Attila Gyorgy

2012-12-01

Full Text Available Social contributions have an important impact on payroll policy. Also, social contributions represent a significant budgetary revenue item which can be viewed at the edge between taxation and insurance. Social contributions in Romania experienced many changes which ended in 2008. Nowadays, they are within a long transaction period towards partial externalization of the insurance activity to privately managed funds. The aim of this paper is to analyse the homogeneity of Romanian social security public scheme using annual data extracted from 2002-2009.The main findings reveal that social contributions reached the pinnacle of diversification, being too many, some of them with a small contribution rates; fiscal reforms which reduced contribution rates advantaged employers, and state will be interested to externalize this activity as far private sector will be able to assume this responsibility and the budgetary effects are acceptable for the public finance.

Lattice specific heat for the RMIn5 (R=Gd, La, Y; M=Co, Rh) compounds: Non-magnetic contribution subtraction

International Nuclear Information System (INIS)

Facio, Jorge I.; Betancourth, D.; Cejas Bolecek, N.R.; Jorge, G.A.; Pedrazzini, Pablo; Correa, V.F.; Cornaglia, Pablo S.; Vildosola, V.; García, D.J.

2016-01-01

We analyze theoretically a common experimental process used to obtain the magnetic contribution to the specific heat of a given magnetic material. In the procedure, the specific heat of a non-magnetic analog is measured and used to subtract the non-magnetic contributions, which are generally dominated by the lattice degrees of freedom in a wide range of temperatures. We calculate the lattice contribution to the specific heat for the magnetic compounds GdMIn 5 (M=Co, Rh) and for the non-magnetic YMIn 5 and LaMIn 5 (M=Co, Rh), using density functional theory based methods. We find that the best non-magnetic analog for the subtraction depends on the magnetic material and on the range of temperatures. While the phonon specific heat contribution of YRhIn 5 is an excellent approximation to the one of GdCoIn 5 in the full temperature range, for GdRhIn 5 we find a better agreement with LaCoIn 5 , in both cases, as a result of an optimum compensation effect between masses and volumes. We present measurements of the specific heat of the compounds GdMIn 5 (M=Co, Rh) up to room temperature where it surpasses the value expected from the Dulong–Petit law. We obtain a good agreement between theory and experiment when we include anharmonic effects in the calculations.

E2 nuclear resonance effects in pionic and kaonic atoms

International Nuclear Information System (INIS)

Batty, C.J.; Biagi, S.F.; Blecher, M.

1977-09-01

The attenuation due to the E2 nuclear resonance effect has been measured in hadronic atoms using pions with 111 Cd and 112 Cd, and for kaons with 122 Sn. Energies of the relevant X-ray and γ-ray transitions and of the X-ray cascade intensities have also been measured so as to give a self-consistent set of information. The results are found to be in very good agreement with theoretical calculations. (author)

Rock glaciers, Zailiysiky Range, Kungei Ranges, Tienshan, Kazakhstan, Version 1

Data.gov (United States)

National Aeronautics and Space Administration — The Zailiyskiy Alatau is the northernmost parallel latitudinal ranges of the Northern Tien Shan. The highest point of this range is the Talgar peak (4973 m a.s.l.)....

The Importance of Short- and Long-Range Exchange on Various Excited State Properties of DNA Monomers, Stacked Complexes, and Watson-Crick Pairs.

Science.gov (United States)

Raeber, Alexandra E; Wong, Bryan M

2015-05-12

We present a detailed analysis of several time-dependent DFT (TD-DFT) methods, including conventional hybrid functionals and two types of nonempirically tuned range-separated functionals, for predicting a diverse set of electronic excitations in DNA nucleobase monomers and dimers. This large and extensive set of excitations comprises a total of 50 different transitions (for each tested DFT functional) that includes several n → π and π → π* valence excitations, long-range charge-transfer excitations, and extended Rydberg transitions (complete with benchmark calculations from high-level EOM-CCSD(T) methods). The presence of localized valence excitations as well as extreme long-range charge-transfer excitations in these systems poses a serious challenge for TD-DFT methods that allows us to assess the importance of both short- and long-range exchange contributions for simultaneously predicting all of these various transitions. In particular, we find that functionals that do not have both short- and full long-range exchange components are unable to predict the different types of nucleobase excitations with the same accuracy. Most importantly, the current study highlights the importance of both short-range exchange and a nonempirically tuned contribution of long-range exchange for accurately predicting the diverse excitations in these challenging nucleobase systems.

Possible manifestation of long range forces in high energy hadron collisions

International Nuclear Information System (INIS)

Kuraev, Eh.A.; Ferro, P.; Trentadue, L.

1997-01-01

Pion-pion and photon-photon scattering are discussed.. We obtain, starting from the impact representation introduced by Cheng and Wu a new contribution to the high energy hadron-hadron scattering amplitude for small transferred momentum q 2 of the form is (q 2 /m 4 )ln(-q 2 /m 2 ). This behaviour may be interpreted as a manifestation of long transverse-range forces between hadrons which, for ρ>> m -1 fall off as ρ -4 . We consider the examples of pion and photon scattering with photons converted in the intermediate state to two pairs of quarks interacting by exchanging two gluon colorless state. A phenomenological approach for proton impact factor is used to analyze proton-proton scattering. The analysis of the lowest order radiative corrections for the case of photon-photon scattering is done. We discuss the possibility of observing the effects of these long range forces

Two-dimensional angular momentum in the presence of long-range magnetic flux

International Nuclear Information System (INIS)

Jackiw, R.; Redlich, A.N.

1983-01-01

It is shown that eigenvalues of two-dimensional angular momentum remain integer valued in the magnetic field of a solenoid, contrary to published assertions that they are modified by the flux. For a vortex, flux does contribute, and the angular momentum can fractionize, as asserted in the literature, provided phases of wave functions are chosen consistently with the solenoid problem. Long-range effects of flux, the distinction between orbital and canonical angular momentum, and interactions with Cooper pairs are essential to this argument

Relationship between welfare and individual ranging behaviour in commercial free-range laying hens.

Science.gov (United States)

Larsen, H; Hemsworth, P H; Cronin, G M; Gebhardt-Henrich, S G; Smith, C L; Rault, J-L

2018-01-24

Laying hens housed in free-range systems have access to an outdoor range, and individual hens within a flock differ in their ranging behaviour. Whether there is a link between ranging and laying hen welfare remains unclear. We analysed the relationships between ranging by individual hens on a commercial free-range layer farm and behavioural, physiological and health measures of animal welfare. We hypothesised that hens that access the range more will be (1) less fearful in general and in response to novelty and humans, (2) have better health in terms of physical body condition and (3) have a reduced physiological stress response to behavioural tests of fear and health assessments than hens that use the range less. Using radio frequency identification tracking across two flocks, we recorded individual hens' frequency, duration and consistency of ranging. We also assessed how far hens ventured into the range based on three zones: 0 to 2.4, 2.4 to 11.4 or >11.4 m from the shed. We assessed hen welfare using a variety of measures including: tonic immobility, open field, novel object, human approach, and human avoidance (HAV) behavioural tests; stress-induced plasma corticosterone response and faecal glucocorticoid metabolites; live weight, comb colour, and beak, plumage, footpad, and keel bone condition. Range use was positively correlated with plasma corticosterone response, faecal glucocorticoid metabolites, and greater flight distance during HAV. Hens that used the range more, moved towards rather than away from the novel object more often than hens that ranged less. Distance ranged from the shed was significantly associated with comb colour and beak condition, in that hens with darker combs and more intact beaks ranged further. Overall the findings suggest that there is no strong link between outdoor range usage and laying hen welfare. Alternatively, it may be that hens that differed in their ranging behaviour showed few differences in measures of welfare because

Relative contributions of transient and steady state infiltration during ephemeral streamflow

Science.gov (United States)

Blasch, Kyle W.; Ferré, Ty P.A.; Hoffmann, John P.; Fleming, John B.

2006-01-01

Simulations of infiltration during three ephemeral streamflow events in a coarse‐grained alluvial channel overlying a less permeable basin‐fill layer were conducted to determine the relative contribution of transient infiltration at the onset of streamflow to cumulative infiltration for the event. Water content, temperature, and piezometric measurements from 2.5‐m vertical profiles within the alluvial sediments were used to constrain a variably saturated water flow and heat transport model. Simulated and measured transient infiltration rates at the onset of streamflow were about two to three orders of magnitude greater than steady state infiltration rates. The duration of simulated transient infiltration ranged from 1.8 to 20 hours, compared with steady state flow periods of 231 to 307 hours. Cumulative infiltration during the transient period represented 10 to 26% of the total cumulative infiltration, with an average contribution of approximately 18%. Cumulative infiltration error for the simulated streamflow events ranged from 9 to 25%. Cumulative infiltration error for typical streamflow events of about 8 hours in duration in is about 90%. This analysis indicates that when estimating total cumulative infiltration in coarse‐grained ephemeral stream channels, consideration of the transient infiltration at the onset of streamflow will improve predictions of the total volume of infiltration that may become groundwater recharge.

Contributions to the sixth international conference on fusion reactor materials

Energy Technology Data Exchange (ETDEWEB)

NONE

1993-11-15

The ICFRM series has documented progress in the field of fusion reactor materials since the first conference held in Tokyo in 1984. The conference series has continually increased its coverage to the point where it now includes the comprehensive range of materials science and technology areas that enable systems designers to meet the needs of current experiments and to present innovative solutions for future energy systems. This publication contains five contributions to the sixth international conference which have each been indexed separately.

Model-based restoration using light vein for range-gated imaging systems.

Science.gov (United States)

Wang, Canjin; Sun, Tao; Wang, Tingfeng; Wang, Rui; Guo, Jin; Tian, Yuzhen

2016-09-10

The images captured by an airborne range-gated imaging system are degraded by many factors, such as light scattering, noise, defocus of the optical system, atmospheric disturbances, platform vibrations, and so on. The characteristics of low illumination, few details, and high noise make the state-of-the-art restoration method fail. In this paper, we present a restoration method especially for range-gated imaging systems. The degradation process is divided into two parts: the static part and the dynamic part. For the static part, we establish the physical model of the imaging system according to the laser transmission theory, and estimate the static point spread function (PSF). For the dynamic part, a so-called light vein feature extraction method is presented to estimate the fuzzy parameter of the atmospheric disturbance and platform movement, which make contributions to the dynamic PSF. Finally, combined with the static and dynamic PSF, an iterative updating framework is used to restore the image. Compared with the state-of-the-art methods, the proposed method can effectively suppress ringing artifacts and achieve better performance in a range-gated imaging system.

Range Reference Atmosphere 0-70 Km Altitude. Kwajalein Missile Range, Kwajalein, Marshall Islands

Science.gov (United States)

1982-01-01

DOCUMENT 360-82 KWAJALEIN MISSILE RANGE KWAJALEIN, MARSHALL ISLANDS RANGE REFERENCE ATMOSPHERE 0-70 KM ALTITUDE, C00 L’’I METEOROLOGY GROUP .RANGE...34Reference Atmosphere (Part 1), Kwajale 4n Missile Range, Kwajalein, Marshall Islands ," ADA002664. * 19. KEY WORDS (Continue on revorsae d. If necoeewy...CLASSIFICATION OF TIlS PAGE (Whe~n Data EnterecD -v DOCUMENT 360-82 Vo- KWAJALEIN MISSILE RANGE KWAJALEIN, MARSHALL ISLANDS RANGE REFERENCE ATMOSPHERE 0-70 km

Satellite laser ranging to low Earth orbiters: orbit and network validation

Science.gov (United States)

Arnold, Daniel; Montenbruck, Oliver; Hackel, Stefan; Sośnica, Krzysztof

2018-04-01

Satellite laser ranging (SLR) to low Earth orbiters (LEOs) provides optical distance measurements with mm-to-cm-level precision. SLR residuals, i.e., differences between measured and modeled ranges, serve as a common figure of merit for the quality assessment of orbits derived by radiometric tracking techniques. We discuss relevant processing standards for the modeling of SLR observations and highlight the importance of line-of-sight-dependent range corrections for the various types of laser retroreflector arrays. A 1-3 cm consistency of SLR observations and GPS-based precise orbits is demonstrated for a wide range of past and present LEO missions supported by the International Laser Ranging Service (ILRS). A parameter estimation approach is presented to investigate systematic orbit errors and it is shown that SLR validation of LEO satellites is not only able to detect radial but also along-track and cross-track offsets. SLR residual statistics clearly depend on the employed precise orbit determination technique (kinematic vs. reduced-dynamic, float vs. fixed ambiguities) but also reveal pronounced differences in the ILRS station performance. Using the residual-based parameter estimation approach, corrections to ILRS station coordinates, range biases, and timing offsets are derived. As a result, root-mean-square residuals of 5-10 mm have been achieved over a 1-year data arc in 2016 using observations from a subset of high-performance stations and ambiguity-fixed orbits of four LEO missions. As a final contribution, we demonstrate that SLR can not only validate single-satellite orbit solutions but also precise baseline solutions of formation flying missions such as GRACE, TanDEM-X, and Swarm.

Drought-induced trans-generational tradeoff between stress tolerance and defence: consequences for range limits?

Science.gov (United States)

Alsdurf, Jacob D; Ripley, Tayler J; Matzner, Steven L; Siemens, David H

2013-01-01

Areas just across species range boundaries are often stressful, but even with ample genetic variation within and among range-margin populations, adaptation towards stress tolerance across range boundaries often does not occur. Adaptive trans-generational plasticity should allow organisms to circumvent these problems for temporary range expansion; however, range boundaries often persist. To investigate this dilemma, we drought stressed a parent generation of Boechera stricta (A.Gray) A. Löve & D. Löve, a perennial wild relative of Arabidopsis, representing genetic variation within and among several low-elevation range margin populations. Boechera stricta is restricted to higher, moister elevations in temperate regions where generalist herbivores are often less common. Previous reports indicate a negative genetic correlation (genetic tradeoff) between chemical defence allocation and abiotic stress tolerance that may prevent the simultaneous evolution of defence and drought tolerance that would be needed for range expansion. In growth chamber experiments, the genetic tradeoff became undetectable among offspring sib-families whose parents had been drought treated, suggesting that the stress-induced trans-generational plasticity may circumvent the genetic tradeoff and thus enable range expansion. However, the trans-generational effects also included a conflict between plastic responses (environmental tradeoff); offspring whose parents were drought treated were more drought tolerant, but had lower levels of glucosinolate toxins that function in defence against generalist herbivores. We suggest that either the genetic or environmental tradeoff between defence allocation and stress tolerance has the potential to contribute to range limit development in upland mustards.

The ILRS Reanalysis 1983 - 2009 Contributed To ITRF2008

Science.gov (United States)

Pavlis, E. C.; Luceri, V.; Sciarretta, C.; Kelm, R.

2009-12-01

For over two decades, Satellite Laser Ranging (SLR) data contribute to the definition of the Terrestrial Reference Frame (TRF). Until the development of ITRF2000, the contributions were submitted in the form of a set of normal equations or a covariance matrix of station coordinates and their linear rates at a standard epoch. The development of ITRF2005 ushered a new era with the use of weekly or session contributions, allowing greater flexibility in the relative weighting and the combination of information from various techniques. Moreover, the need of a unique, official, representative solution for each Technique Service, based on the rigorous combination of the various Analysis Centers’ contributions, gave the opportunity to all techniques to verify, as a first step, the intra-technique solution consistency and, immediately after, to engage in discussions and comparison of the internal procedures, leading to a harmonization and validation of these procedures and the adopted models in the inter-technique context. In many occasions, the time series approach joint with the intra- and inter-technique comparison steps also highlighted differences that previously went unnoticed, and corrected incompatibilities. During the past year we have been preparing the ILRS contribution to a second TRF developed in the same way, the ITRF2008. The ILRS approach is based strictly on the current IERS Conventions 2003 and our internal standards. The Unified Analysis Workshop in 2007 stressed a number of areas where each technique needed to focus more attention in future analyses. In the case of SLR, the primary areas of concern were tracking station biases, extending the data span used in the analysis, and target characteristics. The present re-analysis extends from 1983 to 2009, covering a 25-year period, the longest for any of the contributing techniques; although the network and data quality for the 1983-1993 period are significantly poorer than for the latter years, the overall

Nutritional contribution of street foods to the diet of people in developing countries: a systematic review.

Science.gov (United States)

Steyn, Nelia Patricia; McHiza, Zandile; Hill, Jillian; Davids, Yul Derek; Venter, Irma; Hinrichsen, Enid; Opperman, Maretha; Rumbelow, Julien; Jacobs, Peter

2014-06-01

To review studies examining the nutritional value of street foods and their contribution to the diet of consumers in developing countries. The electronic databases PubMed/MEDLINE, Web of Science, Cochrane Library, Proquest Health and Science Direct were searched for articles on street foods in developing countries that included findings on nutritional value. From a total of 639 articles, twenty-three studies were retained since they met the inclusion criteria. In summary, daily energy intake from street foods in adults ranged from 13 % to 50 % of energy and in children from 13 % to 40 % of energy. Although the amounts differed from place to place, even at the lowest values of the percentage of energy intake range, energy from street foods made a significant contribution to the diet. Furthermore, the majority of studies suggest that street foods contributed significantly to the daily intake of protein, often at 50 % of the RDA. The data on fat and carbohydrate intakes are of some concern because of the assumed high contribution of street foods to the total intakes of fat, trans-fat, salt and sugar in numerous studies and their possible role in the development of obesity and non-communicable diseases. Few studies have provided data on the intake of micronutrients, but these tended to be high for Fe and vitamin A while low for Ca and thiamin. Street foods make a significant contribution to energy and protein intakes of people in developing countries and their use should be encouraged if they are healthy traditional foods.

Hardware test program for evaluation of baseline range/range rate sensor concept

Science.gov (United States)

Pernic, E.

1985-01-01

The test program Phase II effort provides additional design information in terms of range and range rate (R/R) sensor performance when observing and tracking a typical spacecraft target. The target used in the test program was a one-third scale model of the Hubble Space Telescope (HST) available at the MSFC test site where the tests were performed. A modified Bendix millimeter wave radar served as the R/R sensor test bed for evaluation of range and range rate tracking performance, and generation of radar signature characteristics of the spacecraft target. A summary of program test results and conclusions are presented along with detailed description of the Bendix test bed radar with accompaning instrumentation. The MSFC test site and facilities are described. The test procedures used to establish background levels, and the calibration procedures used in the range accuracy tests and RCS (radar cross section) signature measurements, are presented and a condensed version of the daily log kept during the 5 September through 17 September test period is also presented. The test program results are given starting with the RCS signature measurements, then continuing with range measurement accuracy test results and finally the range and range rate tracking accuracy test results.

Tonopah Test Range - Index

Science.gov (United States)

Capabilities Test Operations Center Test Director Range Control Track Control Communications Tracking Radars Photos Header Facebook Twitter YouTube Flickr RSS Tonopah Test Range Top TTR_TOC Tonopah is the testing range of choice for all national security missions. Tonopah Test Range (TTR) provides research and

High Precision Ranging and Range-Rate Measurements over Free-Space-Laser Communication Link

Science.gov (United States)

Yang, Guangning; Lu, Wei; Krainak, Michael; Sun, Xiaoli

2016-01-01

We present a high-precision ranging and range-rate measurement system via an optical-ranging or combined ranging-communication link. A complete bench-top optical communication system was built. It included a ground terminal and a space terminal. Ranging and range rate tests were conducted in two configurations. In the communication configuration with 622 data rate, we achieved a two-way range-rate error of 2 microns/s, or a modified Allan deviation of 9 x 10 (exp -15) with 10 second averaging time. Ranging and range-rate as a function of Bit Error Rate of the communication link is reported. They are not sensitive to the link error rate. In the single-frequency amplitude modulation mode, we report a two-way range rate error of 0.8 microns/s, or a modified Allan deviation of 2.6 x 10 (exp -15) with 10 second averaging time. We identified the major noise sources in the current system as the transmitter modulation injected noise and receiver electronics generated noise. A new improved system will be constructed to further improve the system performance for both operating modes.

Triple nitrate isotopes indicate differing nitrate source contributions to streams across a nitrogen saturation gradient

Science.gov (United States)

Lucy A. Rose; Emily M. Elliott; Mary Beth. Adams

2015-01-01

Nitrogen (N) deposition affects forest biogeochemical cycles worldwide, often contributing to N saturation. Using long-term (>30-year) records of stream nitrate (NO3-) concentrations at Fernow Experimental Forest (West Virginia, USA), we classified four watersheds into N saturation stages ranging from Stage 0 (N-...

Isobar contributions to the imaginary part of the optical-model potential for finite nuclei

International Nuclear Information System (INIS)

Hjort-Jensen, M.; Borromeo, M.; Muether, H.; Polls, A.

1992-03-01

A recently developed non-relativistic method for calculating the nucleon optical-model potential has been employed to evaluate the contributions from isobaric degrees of freedom to the imaginary part of the nucleon optical-model potential. To evaluate the imaginary part of the optical-model potential, the authors include the contributions from terms to second order in the Brueckner G-matrix with and without the inclusion of isobars Δ. Results for 16 O are presented in this work. The contributions to the imaginary part are given by the two-particle-one-hole (2p1h) and three-particle-two-hole (3p2h) diagrams. The latter contributes at negative energies only and the contribution from isobar intermediate states is rather small. The 2p1h receives significant contributions from isobars at energies near the resonance and above the threshold for the excitation of ΔΔ states. In particular, the importance of ΔΔ configurations is rather sensitive to the treatment of short-range correlations. The parameterization of the self-energy in terms of local potentials is discussed. The depletion of the occupation of the single-particle orbits due to nucleon-nucleon correlations and Δ excitations is evaluated. 49 refs., 14 figs., 3 tabs

Are starburst galaxies proton calorimeters?

Science.gov (United States)

Wang, Xilu; Fields, Brian D.

2018-03-01

Several starburst galaxies have been observed in the GeV and TeV bands. In these dense environments, gamma-ray emission should be dominated by cosmic ray (CR) interactions with the interstellar medium (pcrpism → π0 → γγ). Indeed, starbursts may act as proton `calorimeters' where a substantial fraction of CR energy input is emitted in gamma-rays. Here, we build a one-zone, `thick-target' model implementing calorimetry and placing a firm upper bound on gamma-ray emission from CR interactions. The model assumes that CRs are accelerated by supernovae (SNe), and all suffer nuclear interactions rather than escape. Our model has only two free parameters: the CR proton acceleration energy per SN ɛcr, and the proton injection spectral index s. We calculate the pionic gamma-ray emission from 10 MeV to 10 TeV, and derive thick-target parameters for six galaxies with Fermi, H.E.S.S., and/or VERITAS data. Our model provides good fits for the M82 and NGC 253, and yields ɛcr and s values suggesting that SN CR acceleration is similar in starbursts and in our Galaxy. We find that these starbursts are indeed nearly if not fully proton calorimeters. For NGC 4945 and NGC 1068, the models are consistent with calorimetry but are less well-constrained due to the lack of TeV data. However, the Circinus galaxy and the ultra-luminous infrared galaxy Arp 220 exceed our pionic upper-limit; possible explanations are discussed.

Characterizing short-range vs. long-range spatial correlations in dislocation distributions

International Nuclear Information System (INIS)

Chevy, Juliette; Fressengeas, Claude; Lebyodkin, Mikhail; Taupin, Vincent; Bastie, Pierre; Duval, Paul

2010-01-01

Hard X-ray diffraction experiments have provided evidence of a strongly heterogeneous distribution of dislocation densities along the axis of cylindrical ice single crystals oriented for basal slip in torsion creep. The dislocation arrangements showed a complex scale-invariant character, which was analyzed by means of statistical and multifractal techniques. A trend to decreasing autocorrelation of the dislocation distribution was observed as deformation proceeds. At low strain levels, long-range spatial correlations control the distribution, but short-range correlations in relation with cross-slip progressively prevail when strain increases. This trend was reproduced by a model based on field dislocation dynamics, a theory accounting for both long-range elastic interactions and short-range interactions through transport of dislocation densities.

Characterizing short-range vs. long-range spatial correlations in dislocation distributions

Energy Technology Data Exchange (ETDEWEB)

Chevy, Juliette, E-mail: juliette.chevy@gmail.com [Laboratoire de Glaciologie et Geophysique de l' Environnement-CNRS, 54 rue Moliere, 38402 St. Martin d' Heres (France)] [Laboratoire Science et Ingenierie des Materiaux et Procedes, Grenoble INP-CNRS-UJF, BP 75, 38402 St. Martin d' Heres Cedex (France); Fressengeas, Claude; Lebyodkin, Mikhail; Taupin, Vincent [Laboratoire de Physique et Mecanique des Materiaux, Universite Paul Verlaine-Metz/CNRS, Ile du Saulcy, 57045 Metz Cedex (France); Bastie, Pierre [Laboratoire de Spectrometrie Physique, BP 87, 38402 St. Martin d' Heres Cedex (France)] [Institut Laue Langevin, BP 156, 38042 Grenoble Cedex 9 (France); Duval, Paul [Laboratoire de Glaciologie et Geophysique de l' Environnement-CNRS, 54 rue Moliere, 38402 St. Martin d' Heres (France)

2010-03-15

Hard X-ray diffraction experiments have provided evidence of a strongly heterogeneous distribution of dislocation densities along the axis of cylindrical ice single crystals oriented for basal slip in torsion creep. The dislocation arrangements showed a complex scale-invariant character, which was analyzed by means of statistical and multifractal techniques. A trend to decreasing autocorrelation of the dislocation distribution was observed as deformation proceeds. At low strain levels, long-range spatial correlations control the distribution, but short-range correlations in relation with cross-slip progressively prevail when strain increases. This trend was reproduced by a model based on field dislocation dynamics, a theory accounting for both long-range elastic interactions and short-range interactions through transport of dislocation densities.

Dispersal limitation at the expanding range margin of an evergreen tree in urban habitats?

DEFF Research Database (Denmark)

Møller, Linda Agerbo; Skou, Anne-Marie Thonning; Kollmann, Johannes Christian

2012-01-01

Dispersal limitations contribute to shaping plant distribution patterns and thus are significant for biodiversity conservation and urban ecology. In fleshy-fruited plants, for example, any preference of frugivorous birds affects dispersal capacities of certain fruit species. We conducted a removal...... landscapes. The results should be included in urban forestry and planting of potentially invasive ornamental species. © 2011 Elsevier GmbH. All rights reserved....... experiment with fruits of Ilex aquifolium, a species that is currently expanding its range margin in northern Europe in response to climate change. The species is also a popular ornamental tree and naturalization has been observed in many parts of its range. Fruits of native I. aquifolium and of three...

Role of the Office International des Epizooties in protecting the health of free-ranging mammals.

Science.gov (United States)

Blancou, J

1992-12-01

The various activities undertaken by the Office International des Epizooties (OIE) since 1924 to protect the helth of free-ranging mammals are outlined and discussed. Two types of activity have been conducted over the years: --The first type promotes measures to protect the health of free-ranging mammals in order to safeguard the health of domestic animals and human beings. These measures have prevented the propagation of the highly contagious diseases of animals and the more serious zoonoses. --The second type aims at protecting the health of free-ranging mammals in order to maintain the fauna and the natural equilibrium. Ecological and epidemiological studies are promoted with a view to effective management of wildlife populations and overcoming the associated health risks. By virtue of its close contacts with officials in charge of animal health in 126 Member Countries, the OIE has made a noteworthy contribution to the protection of populations of free-ranging mammals.

Biofilms' contribution to organic carbon in salt marsh sediments

Science.gov (United States)

Valentine, K.; Quirk, T. E.; Mariotti, G.; Hotard, A.

2017-12-01

Coastal salt marshes are productive environments with high potential for carbon (C) accumulation. Organic C in salt marsh sediment is typically attributed to plant biomass. Recent field measurements, however, suggest that biofilms - mainly composed of benthic diatoms and their secretion - also contribute to basal C in these environments and can be important contributors to marsh productivity, C cycling, and potentially, C sequestration. The potential for biofilms to soil organic C and the influence of mineral sedimentation of biofilm-based C accumulation is unknown. We conducted controlled laboratory experiments to test (1) whether biofilms add measurable amounts of organic C to the sediment and (2) the effect of mineral sedimentation rate on the amount of biofilm-based C accumulation. Settled beds of pure bentonite mud were created in 10-cm-wide cylinders. Each cylinder was inoculated with biofilms collected from a marsh in Louisiana. A small amount of mud was added weekly for 11 weeks. Control experiments without biofilms were also performed. Biofilms were grown with a 12/12 hours cycle, with a gentle mixing of the water column that did not cause sediment resuspension, with a nutrient-rich medium that was exchanged weekly, and in the absence of metazoan grazing. At the end of the experiment, the sediment columns were analyzed for depth-integrated chl-a, loss on ignition (LOI), and total organic carbon (TOC). Chl-a values ranged from 26-113 mg/cm2, LOI values ranged from 86-456 g/m2/yr, and TOC values ranged from 31-211 g/m2/yr. All three of these metrics (chl-a, LOI, and TOC) increased with the rate of mineral sedimentation. These results show that biofilms, in the absence of erosion and grazing, can significantly contribute to C accumulation in salt marshes, especially with high rates of mineral sedimentation. Given the short time scale of the experiment, the increase in organic C accumulation with the rate of sedimentation is attributed to stimulated biofilm

The ILRS Contribution to ITRF2013

Science.gov (United States)

Pavlis, Erricos C.; Luceri, Cinzia; Sciarretta, Cecilia; Evans, Keith

2014-05-01

Satellite Laser Ranging (SLR) data have contributed to the definition of the International Terrestrial Reference Frame (ITRF) over the past three decades. The development of ITRF2005 ushered a new era with the use of weekly or session contributions, allowing greater flexibility in the editing, relative weighting and the combination of information from the four contributing techniques. The new approach allows each Service to generate a solution based on the rigorous combination of the individual Analysis Centers' contributions that provides an opportunity to verify the intra-technique consistency and a comparison of internal procedures and adopted models. The intra- and inter-technique comparisons that the time series approach facilitates are an extremely powerful diagnostic that highlights differences and inconsistencies at the single station level. Over the past year the ILRS Analysis Working Group (AWG) worked on designing an improved ILRS contribution for the development of ITRF2013. The ILRS approach is based on the current IERS Conventions 2010 and our internal ILRS standards, with a few deviations that are documented. Since the Global Geodetic Observing System - GGOS identified the ITRF as its key project, the ILRS has taken a two-pronged approach in order to meet its stringent goals: modernizing the engineering components (ground and space segments), and revising the modeling standards taking advantage of recent improvements in system Earth modeling. The main concern in the case of SLR is monitoring systematic errors at individual stations, accounting for undocumented discontinuities, and improving the target signature models. The latter has been addressed with the adoption of mm-level models for all of our targets. As far as the station systematics, the AWG had already embarked on a major effort to improve the handling of such errors prior to the development of ITRF2008. The results of that effort formed the foundation for the re-examination of the

Study of the proper contribution of independent power producing business in the long-range power supply and demand plan

Energy Technology Data Exchange (ETDEWEB)

Jo, S.B. [Korea Energy Economics Institute, Euiwang (Korea, Republic of)

1997-12-01

The independent power producing business has expanded its size and process through the Long-range Power Supply and Demand Plan of 1993, 1995, and it is high time that full-scale competition in the power generation market began to emerge. This report assesses the marginal costs of independent and general power producing businesses on a theoretical basis on the proper size of independent power producing business, and presents the methods to compare these. But, since there follows several problems in applying this theoretical model, a practical standard to decide the proper level of independent power production amount is presented. That is, while not much burdening the existing industrial structure, I search for ways to present the amount of independent power production and the methods of power generation to make sure that the competition effect is maximized when full-scale competition started. However, in the long-term, the allotment of independent power production itself could be a violation to the basic spirit of competition. A more desirable way is to allow independent power producers and the Korea Power Corp. to freely compete on all types of power generation and facilities. The supply plan should be also operated smoothly and flexibly since the types of power generation and the amounts reflect the result of competition not the predetermined ones. Therefore, a long-range power supply and demand plan should be converted from a planning-oriented concept to a market-oriented base with the structural overhaul of the power generation industry for the effective resources distribution of power supply facilities. 18 refs., 2 figs., 7 tabs.

Perfomance of a high purity germanium multi-detector telescope for long range particles

International Nuclear Information System (INIS)

Riepe, G.; Protic, D.; Suekoesd, C.; Didelez, J.P.; Frascaria, N.; Gerlic, E.; Hourani, E.; Morlet, M.

1980-01-01

A telescope of stacked high purity germanium detectors designed for long range charged particles was tested using medium energy protons. Particle identification and the rejection of the low energy tail could be accomplished on-line allowing the measurement of complex spectra. The efficiency of the detector stack for protons was measured up to 156 MeV incoming energy. The various factors affecting the energy resolution are discussed and their estimated contributions are compared with the experimental results

Improved linearity using harmonic error rejection in a full-field range imaging system

Science.gov (United States)

Payne, Andrew D.; Dorrington, Adrian A.; Cree, Michael J.; Carnegie, Dale A.

2008-02-01

Full field range imaging cameras are used to simultaneously measure the distance for every pixel in a given scene using an intensity modulated illumination source and a gain modulated receiver array. The light is reflected from an object in the scene, and the modulation envelope experiences a phase shift proportional to the target distance. Ideally the waveforms are sinusoidal, allowing the phase, and hence object range, to be determined from four measurements using an arctangent function. In practice these waveforms are often not perfectly sinusoidal, and in some cases square waveforms are instead used to simplify the electronic drive requirements. The waveforms therefore commonly contain odd harmonics which contribute a nonlinear error to the phase determination, and therefore an error in the range measurement. We have developed a unique sampling method to cancel the effect of these harmonics, with the results showing an order of magnitude improvement in the measurement linearity without the need for calibration or lookup tables, while the acquisition time remains unchanged. The technique can be applied to existing range imaging systems without having to change or modify the complex illumination or sensor systems, instead only requiring a change to the signal generation and timing electronics.

Scanning tunneling spectroscopy to probe odd-triplet contributions to the long-ranged proximity effect in Al-EuS

Energy Technology Data Exchange (ETDEWEB)

Diesch, Simon; Machon, Peter; Belzig, Wolfgang; Scheer, Elke [Universitaet Konstanz, Konstanz (Germany); Suergers, Christoph; Beckmann, Detlef [Karlsruhe Institute of Technology, Karlsruhe (Germany)

2016-07-01

Experiments on superconductor-ferromagnet-systems have shown Cooper pairs tunneling through ferromagnetic layers, indicating Cooper pairs of equal spin, thus corresponding to a long-range triplet proximity effect. Most experimental evidence for triplet superconductivity comes from observations of the thickness dependence of the Josephson current through a ferromagnetic barrier, but there is an increasing interest in obtaining direct spectroscopic evidence. This project aims to analyze the DOS of thin films of the ferromagnetic insulator europium sulfide on superconducting aluminum or vice versa, using a scanning tunneling microscope in spectroscopy mode at 280 mK and in varying magnetic fields. We observe significant broadening of the superconducting energy gap and a variety of sub-gap structures induced by the presence of the ferromagnet and interpret our findings based on the diffusive theory.

Influence of retardation effects on photodisintegration of a quantum system bound by short-range forces

International Nuclear Information System (INIS)

Preobrazhenskii, M.A.; Golovinskii, P.A.

1996-01-01

Expressions for cross sections for multiphonon disintegration of quantum systems bound by short-range forces are obtained in the plane-wave approximation taking into account retardation effects. It is shown that, in the region of nonrelativistic energies, their contribution is factored, and the resulting universal factor is expressed for an arbitrary degree of process nonlinearity n in terms of elementary functions. Arguments of functions are determined only by the mode ω, the radiation spectrum width β, and the bound-state energy of a system. The dependence of the contribution of retardation effects on ω, β, and n is studied in detail. Analytical expressions for cross sections for multiquantum disintegration in the first nonvanishing order with respect to correlation interaction, which exactly take into account retardation effects, are obtained. It is shown that for two-quantum processes, the contribution of correlation effects is expressed in terms of a function representing an extension of dipole polarizability, whereas for n>2, it can be described in the dipole approximation

Free Range Hens Use the Range More When the Outdoor Environment Is Enriched

Directory of Open Access Journals (Sweden)

T. A. D. Nagle

2012-04-01

Full Text Available To evaluate the role of using forage, shade and shelterbelts in attracting birds into the range, three trials were undertaken with free range layers both on a research facility and on commercial farms. Each of the trials on the free range research facility in South Australia used a total of 120 laying hens (Hyline Brown. Birds were housed in an eco-shelter which had 6 internal pens of equal size with a free range area adjoining the shelter. The on-farm trials were undertaken on commercial free range layer farms in the Darling Downs in Southeast Queensland with bird numbers on farms ranging from 2,000–6,800 hens. The first research trial examined the role of shaded areas in the range; the second trial examined the role of forage and the third trial examined the influence of shelterbelts in the range. These treatments were compared to a free range area with no enrichment. Aggressive feather pecking was only observed on a few occasions in all of the trials due to the low bird numbers housed. Enriching the free range environment attracted more birds into the range. Shaded areas were used by 18% of the hens with a tendency (p = 0.07 for more hens to be in the paddock. When forage was provided in paddocks more control birds (55% were observed in the range in morning than in the afternoon (30% while for the forage treatments 45% of the birds were in the range both during the morning and afternoon. When shelterbelts were provided there was a significantly (p<0.05 higher % of birds in the range (43% vs. 24% and greater numbers of birds were observed in areas further away from the poultry house. The results from the on-farm trials mirrored the research trials. Overall 3 times more hens used the shaded areas than the non shaded areas, with slightly more using the shade in the morning than in the afternoon. As the environmental temperature increased the number of birds using the outdoor shade also increased. Overall 17 times more hens used the shelterbelt

How organic carbon derived from multiple sources contributes to carbon sequestration processes in a shallow coastal system?

Science.gov (United States)

Watanabe, Kenta; Kuwae, Tomohiro

2015-04-16

Carbon captured by marine organisms helps sequester atmospheric CO 2 , especially in shallow coastal ecosystems, where rates of primary production and burial of organic carbon (OC) from multiple sources are high. However, linkages between the dynamics of OC derived from multiple sources and carbon sequestration are poorly understood. We investigated the origin (terrestrial, phytobenthos derived, and phytoplankton derived) of particulate OC (POC) and dissolved OC (DOC) in the water column and sedimentary OC using elemental, isotopic, and optical signatures in Furen Lagoon, Japan. Based on these data analysis, we explored how OC from multiple sources contributes to sequestration via storage in sediments, water column sequestration, and air-sea CO 2 exchanges, and analyzed how the contributions vary with salinity in a shallow seagrass meadow as well. The relative contribution of terrestrial POC in the water column decreased with increasing salinity, whereas autochthonous POC increased in the salinity range 10-30. Phytoplankton-derived POC dominated the water column POC (65-95%) within this salinity range; however, it was minor in the sediments (3-29%). In contrast, terrestrial and phytobenthos-derived POC were relatively minor contributors in the water column but were major contributors in the sediments (49-78% and 19-36%, respectively), indicating that terrestrial and phytobenthos-derived POC were selectively stored in the sediments. Autochthonous DOC, part of which can contribute to long-term carbon sequestration in the water column, accounted for >25% of the total water column DOC pool in the salinity range 15-30. Autochthonous OC production decreased the concentration of dissolved inorganic carbon in the water column and thereby contributed to atmospheric CO 2 uptake, except in the low-salinity zone. Our results indicate that shallow coastal ecosystems function not only as transition zones between land and ocean but also as carbon sequestration filters. They

Exclusive measurements of Δ excitation by the (3He,t) reaction

International Nuclear Information System (INIS)

Hennino, Th.

1993-12-01

The production of Δ in nuclei through charge exchange reactions induced by medium energy light projectiles has been undertaken at Laboratoire National Saturne. The possible existence of a pionic collective mode built on Δ-hole correlations has been proposed to explain medium effects which appeared in inclusive experiments. Using the Diogene 4π apparatus to detect the charged particles, the decay pattern of the Δ-hole states has been separated into its different modes. 3 of them deserve particular attention: the quasi free Δ production, the two nucleon absorption channel and the coherent mode. (author). 17 refs., 10 figs

Nuclear Compton scattering

International Nuclear Information System (INIS)

Christillin, P.

1986-01-01

The theory of nuclear Compton scattering is reformulated with explicit consideration of both virtual and real pionic degrees of freedom. The effects due to low-lying nuclear states, to seagull terms, to pion condensation and to the Δ dynamics in the nucleus and their interplay in the different energy regions are examined. It is shown that all corrections to the one-body terms, of diffractive behaviour determined by the nuclear form factor, have an effective two-body character. The possibility of using Compton scattering as a complementary source of information about nuclear dynamics is restressed. (author)

Cascade Processes in Muonic Hydrogen Atoms

International Nuclear Information System (INIS)

Faifman, M. P.; Men'Shikov, L. I.

2001-01-01

The QCMC scheme created earlier for cascade calculations in heavy hadronic atoms of hydrogen isotopes has been modified and applied to the study of cascade processes in the μp muonic hydrogen atoms. The distribution of μp atoms over kinetic energies has been obtained and the yields of K-series X-rays per one stopped muon have been calculated.Comparison with experimental data indicated directly that for muonic and pionic atoms new types of non-radiative transitions are essential, while they are negligible for heavy (kaonic, antiprotonic, etc.) atoms. These processes have been considered and their probabilities have been estimated.

Search for dibaryonic de-excitations in relativistic nuclear reactions

International Nuclear Information System (INIS)

Besliu, C.; Popa, V.; Popa, L.; Topor Pop, V.

1992-08-01

Some old characteristics are observed in the single particle distributions obtained from He + Li interactions at 4.5 A GeV/c momenta, which are explained as the manifestation of a few mechanism of strangeness production via dibaryonic de-excitations. A signature of formation of hadronic and baryonic clusters is also reported. The di-pionic signals of the dibaryonic orbital de-excitations are analysed in the frame of the MIT-bag model and the Monte Carlo simulation. The role played by the dibaryonic resonances in the relativistic nuclear collisions could be a significant one. (author). 23 refs, 5 figs, 1 tab

Search for dibaryonic de-excitations in relativistic nuclear reactions

International Nuclear Information System (INIS)

Besliu, C.; Popa, V.; Popa, L.; Topor Pop, V.

1993-08-01

Some odd characteristics are observed in the single particle distributions obtained from He + Li interactions at 4.5AGeV/c momenta which are explained as the manifestation of a new mechanism of strangeness production via dibaryonic de-excitations. A signature of the formation of hadronic and baryonic clusters is also reported. The di- pionic signals of the dibaryonic orbital de- excitations are analyzed in the frame of the MIT -bag Model and a Monte Carlo simulation. The role played by the dibaryonic resonances in relativistic nuclear collisions could be a significant one. (author). 29 refs, 7 figs

Δ-nucleus dynamics

International Nuclear Information System (INIS)

Hennino, Th.

1993-12-01

The production of Δ in nuclei through charge exchange reactions induced by medium energy light projectiles has been undertaken at Laboratoire National Saturne. The possible existence of a pionic collective mode built on Δ-hole correlations has been proposed to explain medium effects which appeared in inclusive experiments. Using 4π detectors to detect the charged particles, the decay pattern of the Δ-hole states has been separated into its different modes. 3 of them deserve particular attention: the quasi free Δ production, the two nucleon absorption channel and the coherent mode. (author). 17 refs., 9 figs

CPLEAR experiment at CERN: Measurement of CP, T and CPT in the neutral kaon system

International Nuclear Information System (INIS)

Adler, R.; Backenstoss, G.; Eckart, B.; Felder, C.; Leimgruber, F.; Pavlopoulos, P.; Polivka, G.; Rickenbach, R.; Santoni, C.; Schietinger, T.; Tauscher, L.; Vlachos, S.; Angelopoulos, A.; Apostolakis, A.; Sakeliou, L.; Aslanides, E.; Bertin, V.; Ealet, A.; Fassnacht, P.; Henry-Couannier, F.

1997-01-01

Using strangeness tagging at production time, CPLEAR measures K 0 /K-bar 0 time-dependent asymmetries in pionic and semileptonic kaon decays. From those, a set of parameters describing CP, T and CPT violation in neutral kaon mixing and decay can be determined. Strangeness tagging at decay time with the lepton charge allows for time-reversal violation to be directly observed with a significance of more than three standard deviations. The precision on each of the CPT violation parameters is discussed. The mass equality of the K 0 and K-bar 0 is tested within 4.x10 -19 GeV

Ranging Behaviour of Commercial Free-Range Broiler Chickens 1: Factors Related to Flock Variability.

Science.gov (United States)

Taylor, Peta S; Hemsworth, Paul H; Groves, Peter J; Gebhardt-Henrich, Sabine G; Rault, Jean-Loup

2017-07-20

Little is known about the ranging behaviour of chickens. Understanding ranging behaviour is required to improve management and shed and range design to ensure optimal ranging opportunities. Using Radio Frequency Identification technology, we tracked 300 individual broiler chickens in each of four mixed sex ROSS 308 flocks on one commercial farm across two seasons. Ranging behaviour was tracked from the first day of range access (21 days of age) until 35 days of age in winter and 44 days of age in summer. Range use was higher than previously reported from scan sampling studies. More chickens accessed the range in summer (81%) than winter (32%; p range use was greater in summer flocks (4.4 ± 0.1 visits for a total of 26.3 ± 0.8 min/day) than winter flocks (3.2 ± 0.2 visits for a total of 7.9 ± 1.0 min/day). Seasonal differences were only marginally explained by weather conditions and may reflect the reduction in range exposure between seasons (number of days, hours per day, and time of day). Specific times of the day ( p ranging and external factors that may explain ranging preferences.

Individual Ranging Behaviour Patterns in Commercial Free-Range Layers as Observed through RFID Tracking.

Science.gov (United States)

Larsen, Hannah; Cronin, Greg M; Gebhardt-Henrich, Sabine G; Smith, Carolynn L; Hemsworth, Paul H; Rault, Jean-Loup

2017-03-09

In this exploratory study, we tracked free-range laying hens on two commercial flocks with Radio Frequency Identification (RFID) technology with the aim to examine individual hen variation in range use. Three distinct outdoor zones were identified at increasing distances from the shed; the veranda [0-2.4 m], close range [2.4-11.4 m], and far range [>11.4 m]. Hens' movements between these areas were tracked using radio frequency identification technology. Most of the hens in both flocks (68.6% in Flock A, and 82.2% in Flock B) accessed the range every day during the study. Of the hens that accessed the range, most hens accessed all three zones (73.7% in Flock A, and 84.5% in Flock B). Hens spent half of their time outdoors in the veranda area. Within-individual consistency of range use (daily duration and frequency) varied considerably, and hens which were more consistent in their daily range use spent more time on the range overall ( p ranging behaviour may help elucidate the implications of ranging for laying hens.

Dual-frequency magnetic particle imaging of the Brownian particle contribution

Energy Technology Data Exchange (ETDEWEB)

Viereck, Thilo, E-mail: t.viereck@tu-bs.de; Kuhlmann, Christian; Draack, Sebastian; Schilling, Meinhard; Ludwig, Frank

2017-04-01

Magnetic particle imaging (MPI) is an emerging medical imaging modality based on the non-linear response of magnetic nanoparticles to an exciting magnetic field. MPI has been recognized as a fast imaging technique with high spatial resolution in the mm range. For some applications of MPI, especially in the field of functional imaging, the determination of the particle mobility (Brownian rotation) is of great interest, as it enables binding detection in MPI. It also enables quantitative imaging in the presence of Brownian-dominated particles, which is otherwise implausible. Discrimination of different particle responses in MPI is possible via the joint reconstruction approach. In this contribution, we propose a dual-frequency acquisition scheme to enhance sensitivity and contrast in the detection of different particle mobilities compared to a standard single-frequency MPI protocol. The method takes advantage of the fact, that the magnetization response of the tracer is strongly frequency-dependent, i.e. for low excitation frequencies a stronger Brownian contribution is observed.

Attenuation and immunogenicity of host-range extended modified vaccinia virus Ankara recombinants.

Science.gov (United States)

Melamed, Sharon; Wyatt, Linda S; Kastenmayer, Robin J; Moss, Bernard

2013-09-23

Modified vaccinia virus Ankara (MVA) is being widely investigated as a safe smallpox vaccine and as an expression vector to produce vaccines against other infectious diseases and cancer. MVA was isolated following more than 500 passages in chick embryo fibroblasts and suffered several major deletions and numerous small mutations resulting in replication defects in human and most other mammalian cells as well as severe attenuation of pathogenicity. Due to the host range restriction, primary chick embryo fibroblasts are routinely used for production of MVA-based vaccines. While a replication defect undoubtedly contributes to safety of MVA, it is worth considering whether host range and attenuation are partially separable properties. Marker rescue transfection experiments resulted in the creation of recombinant MVAs with extended mammalian cell host range. Here, we characterize two host-range extended rMVAs and show that they (i) have acquired the ability to stably replicate in Vero cells, which are frequently used as a cell substrate for vaccine manufacture, (ii) are severely attenuated in immunocompetent and immunodeficient mouse strains following intranasal infection, (iii) are more pathogenic than MVA but less pathogenic than the ACAM2000 vaccine strain at high intracranial doses, (iv) do not form lesions upon tail scratch in mice in contrast to ACAM2000 and (v) induce protective humoral and cell-mediated immune responses similar to MVA. The extended host range of rMVAs may be useful for vaccine production. Published by Elsevier Ltd.

Free range hens use the range more when the outdoor environment is enriched.

Science.gov (United States)

Nagle, T A D; Glatz, P C

2012-04-01

To evaluate the role of using forage, shade and shelterbelts in attracting birds into the range, three trials were undertaken with free range layers both on a research facility and on commercial farms. Each of the trials on the free range research facility in South Australia used a total of 120 laying hens (Hyline Brown). Birds were housed in an eco-shelter which had 6 internal pens of equal size with a free range area adjoining the shelter. The on-farm trials were undertaken on commercial free range layer farms in the Darling Downs in Southeast Queensland with bird numbers on farms ranging from 2,000-6,800 hens. The first research trial examined the role of shaded areas in the range; the second trial examined the role of forage and the third trial examined the influence of shelterbelts in the range. These treatments were compared to a free range area with no enrichment. Aggressive feather pecking was only observed on a few occasions in all of the trials due to the low bird numbers housed. Enriching the free range environment attracted more birds into the range. Shaded areas were used by 18% of the hens with a tendency (p = 0.07) for more hens to be in the paddock. When forage was provided in paddocks more control birds (55%) were observed in the range in morning than in the afternoon (30%) while for the forage treatments 45% of the birds were in the range both during the morning and afternoon. When shelterbelts were provided there was a significantly (prange (43% vs. 24%) and greater numbers of birds were observed in areas further away from the poultry house. The results from the on-farm trials mirrored the research trials. Overall 3 times more hens used the shaded areas than the non shaded areas, with slightly more using the shade in the morning than in the afternoon. As the environmental temperature increased the number of birds using the outdoor shade also increased. Overall 17 times more hens used the shelterbelt areas than the control areas, with slightly

Newcastle disease and infectious bursal disease among free range village chickens in Tanzania

International Nuclear Information System (INIS)

Yongolo, M.G.S.; Maeda Machangu, A.; Minga, U.M.

2002-01-01

Newcastle disease in free-range village chickens was confirmed by retrospective data analysis and epidemiological cross-sectional studies. The combination of serological survey and virus isolation and characterisation established seasonal occurrence of Newcastle disease (ND) in free-range village chickens. The highest sero-prevalence (81.5) and virus isolation frequency (18/27) were found in the period between June and October. The field isolates of Newcastle virus (NDV) were confirmed to be PMV-1 serotype by polyclonal PMV-1 antiserum and monoclonal antibody (mAb) U85. All isolates were not inhibited by mAb 716/161 specific for pigeon panzootic NDV, showing that the current Tanzanian field isolates have antigenic variation and were not involved in the recent pigeon NDV panzootic. Mean death time determination characterised isolates into velogenic, mesogenic and lentogenic pathotypes. Isolation of NDV from apparently healthy ducks revealed the role of ducks in the epidemiology of ND in free-range village chickens in Tanzania. Studies are recommended to determine the similarities of the field isolates from different sources within Tanzania and to panzootic NDV from other countries. Strategic control of ND in free-range village chickens is recommended taking into consideration the presence of different age groups. Infectious bursal disease was histologically diagnosed in free-range village chickens. Therefore, there is a need of carrying out research on the role of other diseases and determine their prevalence and their contribution to the mortalities experienced in the free-range village chickens. (author)

Supersymmetric contributions to B→DK and the determination of angle γ

International Nuclear Information System (INIS)

Khalil, S.

2007-01-01

We analyze supersymmetric contributions to the branching ratios and CP asymmetries of B - →D 0 K - and B - →anti D 0 K - processes. We investigate the possibility that supersymmetric CP violating phases can affect our determination for the angle γ in the unitary triangle of Cabibbo-Kobayashi-Maskawa mixing matrix. We calculate the gluino and chargino contributions to b→u(anti cs) and b→c(anti us) transitions in a model independent way by using the mass insertion approximation method. We also revise the D 0 - anti D 0 mixing constraints on the mass insertions between the first and second generations of the up sector. We emphasize that in case of negligible D 0 - anti D 0 mixing, one should consider simultaneous contributions from more than one mass insertion in order to be able to obtain the CP asymmetries of these processes within their 1σ experimental range. However, with a large D 0 - anti D 0 mixing, one finds a significant deviation between the two asymmetries and it becomes natural to have them of the order of the central values of their experimental measurements. (orig.)

Low susceptibility of invasive red lionfish (Pterois volitans) to a generalist ectoparasite in both its introduced and native ranges.

Science.gov (United States)

Sikkel, Paul C; Tuttle, Lillian J; Cure, Katherine; Coile, Ann Marie; Hixon, Mark A

2014-01-01

Escape from parasites in their native range is one of many mechanisms that can contribute to the success of an invasive species. Gnathiid isopods are blood-feeding ectoparasites that infest a wide range of fish hosts, mostly in coral reef habitats. They are ecologically similar to terrestrial ticks, with the ability to transmit blood-borne parasites and cause damage or even death to heavily infected hosts. Therefore, being highly resistant or highly susceptible to gnathiids can have significant fitness consequences for reef-associated fishes. Indo-Pacific red lionfish (Pterois volitans) have invaded coastal habitats of the western tropical and subtropical Atlantic and Caribbean regions. We assessed the susceptibility of red lionfish to parasitic gnathiid isopods in both their native Pacific and introduced Atlantic ranges via experimental field studies during which lionfish and other, ecologically-similar reef fishes were caged and exposed to gnathiid infestation on shallow coral reefs. Lionfish in both ranges had very few gnathiids when compared with other species, suggesting that lionfish are not highly susceptible to infestation by generalist ectoparasitic gnathiids. While this pattern implies that release from gnathiid infestation is unlikely to contribute to the success of lionfish as invaders, it does suggest that in environments with high gnathiid densities, lionfish may have an advantage over species that are more susceptible to gnathiids. Also, because lionfish are not completely resistant to gnathiids, our results suggest that lionfish could possibly have transported blood parasites between their native Pacific and invaded Atlantic ranges.

Contribution mapping: a method for mapping the contribution of research to enhance its impact

Science.gov (United States)

2012-01-01

Background At a time of growing emphasis on both the use of research and accountability, it is important for research funders, researchers and other stakeholders to monitor and evaluate the extent to which research contributes to better action for health, and find ways to enhance the likelihood that beneficial contributions are realized. Past attempts to assess research 'impact' struggle with operationalizing 'impact', identifying the users of research and attributing impact to research projects as source. In this article we describe Contribution Mapping, a novel approach to research monitoring and evaluation that aims to assess contributions instead of impacts. The approach focuses on processes and actors and systematically assesses anticipatory efforts that aim to enhance contributions, so-called alignment efforts. The approach is designed to be useful for both accountability purposes and for assisting in better employing research to contribute to better action for health. Methods Contribution Mapping is inspired by a perspective from social studies of science on how research and knowledge utilization processes evolve. For each research project that is assessed, a three-phase process map is developed that includes the main actors, activities and alignment efforts during research formulation, production and knowledge extension (e.g. dissemination and utilization). The approach focuses on the actors involved in, or interacting with, a research project (the linked actors) and the most likely influential users, who are referred to as potential key users. In the first stage, the investigators of the assessed project are interviewed to develop a preliminary version of the process map and first estimation of research-related contributions. In the second stage, potential key-users and other informants are interviewed to trace, explore and triangulate possible contributions. In the third stage, the presence and role of alignment efforts is analyzed and the preliminary

Lattice specific heat for the RMIn{sub 5} (R=Gd, La, Y; M=Co, Rh) compounds: Non-magnetic contribution subtraction

Energy Technology Data Exchange (ETDEWEB)

Facio, Jorge I., E-mail: jorge.facio@cab.cnea.gov.ar [Centro Atómico Bariloche and Instituto Balseiro, CNEA, 8400 Bariloche (Argentina); Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) (Argentina); Betancourth, D.; Cejas Bolecek, N.R. [Centro Atómico Bariloche and Instituto Balseiro, CNEA, 8400 Bariloche (Argentina); Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) (Argentina); Jorge, G.A. [Instituto de Ciencias, Universidad Nacional de General Sarmiento, Buenos Aires (Argentina); Pedrazzini, Pablo; Correa, V.F.; Cornaglia, Pablo S. [Centro Atómico Bariloche and Instituto Balseiro, CNEA, 8400 Bariloche (Argentina); Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) (Argentina); Vildosola, V. [Centro Atómico Constituyentes, CNEA, 1650 San Martín, Buenos Aires (Argentina); Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) (Argentina); García, D.J. [Centro Atómico Bariloche and Instituto Balseiro, CNEA, 8400 Bariloche (Argentina); Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) (Argentina)

2016-06-01

We analyze theoretically a common experimental process used to obtain the magnetic contribution to the specific heat of a given magnetic material. In the procedure, the specific heat of a non-magnetic analog is measured and used to subtract the non-magnetic contributions, which are generally dominated by the lattice degrees of freedom in a wide range of temperatures. We calculate the lattice contribution to the specific heat for the magnetic compounds GdMIn{sub 5} (M=Co, Rh) and for the non-magnetic YMIn{sub 5} and LaMIn{sub 5} (M=Co, Rh), using density functional theory based methods. We find that the best non-magnetic analog for the subtraction depends on the magnetic material and on the range of temperatures. While the phonon specific heat contribution of YRhIn{sub 5} is an excellent approximation to the one of GdCoIn{sub 5} in the full temperature range, for GdRhIn{sub 5} we find a better agreement with LaCoIn{sub 5}, in both cases, as a result of an optimum compensation effect between masses and volumes. We present measurements of the specific heat of the compounds GdMIn{sub 5} (M=Co, Rh) up to room temperature where it surpasses the value expected from the Dulong–Petit law. We obtain a good agreement between theory and experiment when we include anharmonic effects in the calculations.

Home range and travels

Science.gov (United States)

Stickel, L.F.; King, John A.

1968-01-01

The concept of home range was expressed by Seton (1909) in the term 'home region,' which Burr (1940, 1943) clarified with a definition of home range and exemplified in a definitive study of Peromyscus in the field. Burt pointed out the ever-changing characteristics of home-range area and the consequent absence of boundaries in the usual sense--a finding verified by investigators thereafter. In the studies summarized in this paper, sizes of home ranges of Peromyscus varied within two magnitudes, approximately from 0.1 acre to ten acres, in 34 studies conducted in a variety of habitats from the seaside dunes of Florida to the Alaskan forests. Variation in sizes of home ranges was correlated with both environmental and physiological factors; with habitat it was conspicuous, both in the same and different regions. Food supply also was related to size of home range, both seasonally and in relation to habitat. Home ranges generally were smallest in winter and largest in spring, at the onset of the breeding season. Activity and size also were affected by changes in weather. Activity was least when temperatures were low and nights were bright. Effects of rainfall were variable. Sizes varied according to sex and age; young mice remained in the parents' range until they approached maturity, when they began to travel more widely. Adult males commonly had larger home ranges than females, although there were a number of exceptions. An inverse relationship between population density and size of home range was shown in several studies and probably is the usual relationship. A basic need for activity and exploration also appeared to influence size of home range. Behavior within the home range was discussed in terms of travel patterns, travels in relation to home sites and refuges, territory, and stability of size of home range. Travels within the home range consisted of repeated use of well-worn trails to sites of food, shelter, and refuge, plus more random exploratory travels

Use of a Bayesian isotope mixing model to estimate proportional contributions of multiple nitrate sources in surface water

International Nuclear Information System (INIS)

Xue Dongmei; De Baets, Bernard; Van Cleemput, Oswald; Hennessy, Carmel; Berglund, Michael; Boeckx, Pascal

2012-01-01

To identify different NO 3 − sources in surface water and to estimate their proportional contribution to the nitrate mixture in surface water, a dual isotope and a Bayesian isotope mixing model have been applied for six different surface waters affected by agriculture, greenhouses in an agricultural area, and households. Annual mean δ 15 N–NO 3 − were between 8.0 and 19.4‰, while annual mean δ 18 O–NO 3 − were given by 4.5–30.7‰. SIAR was used to estimate the proportional contribution of five potential NO 3 − sources (NO 3 − in precipitation, NO 3 − fertilizer, NH 4 + in fertilizer and rain, soil N, and manure and sewage). SIAR showed that “manure and sewage” contributed highest, “soil N”, “NO 3 − fertilizer” and “NH 4 + in fertilizer and rain” contributed middle, and “NO 3 − in precipitation” contributed least. The SIAR output can be considered as a “fingerprint” for the NO 3 − source contributions. However, the wide range of isotope values observed in surface water and of the NO 3 − sources limit its applicability. - Highlights: ► The dual isotope approach (δ 15 N- and δ 18 O–NO 3 − ) identify dominant nitrate sources in 6 surface waters. ► The SIAR model estimate proportional contributions for 5 nitrate sources. ► SIAR is a reliable approach to assess temporal and spatial variations of different NO 3 − sources. ► The wide range of isotope values observed in surface water and of the nitrate sources limit its applicability. - This paper successfully applied a dual isotope approach and Bayesian isotopic mixing model to identify and quantify 5 potential nitrate sources in surface water.

Magnetic local time dependence of geomagnetic disturbances contributing to the AU and AL indices

DEFF Research Database (Denmark)

Tomita, S; Nose´, M; Iyemori, T

2010-01-01

activity in the auroral zone. In the present study, we examine magnetic local time (MLT) dependence of geomagnetic field variations contributing to the AU and AL indices. We use 1-min geomagnetic field data obtained in 2003. It is found that both AU and AL indices have two ranges of MLT (AU: 15:00-22:00MLT...

Strange Quark Contributions to Parity-Violating Asymmetries in the Forward G0 Electron-Proton Scattering Experiment

Energy Technology Data Exchange (ETDEWEB)

David Armstrong; Francois Arvieux; Razmik Asaturyan; Todd Averett; Stephanie Bailey; Guillaume Batigne; Douglas Beck; Elizabeth Beise; Jay Benesch; Louis Bimbot; James Birchall; Angela Biselli; Peter Bosted; Elodie Boukobza; Herbert Breuer; Roger Carlini; R. Carr; Nicholas Chant; Yu-Chiu Chao; Swapan Chattopadhyay; Russell Clark; Silviu Covrig; Anthony Cowley; Daniel Dale; C. Davis; Willie Falk; John Finn; Tony Forest; Gregg Franklin; Christophe Furget; David Gaskell; Joseph Grames; Keith Griffioen; Klaus Grimm; Benoit Guillon; Hayko Guler; Lars Hannelius; R. Hasty; A. Hawthorne Allen; Tanja Horn; Kathleen Johnston; Mark Jones; Peter Kammel; Reza Kazimi; Paul King; Ameya Kolarkar; Elie Korkmaz; Wolfgang Korsch; Serge Kox; Joachim Kuhn; Jeff Lachniet; Lawrence Lee; Jason Lenoble; Eric Liatard; J. Liu; Berenice Loupias; A. Lung; Glen MacLachlan; Dominique Marchand; J.W. Martin; Kenneth McFarlane; Daniella Mckee; Robert McKeown; Fernand Merchez; Hamlet Mkrtchyan; Bryan Moffit; M. Morlet; Itaru Nakagawa; Kazutaka Nakahara; Melissa Nakos; Retief Neveling; Silvia Niccolai; S. Ong; Shelley Page; Vassilios Papavassiliou; Stephen Pate; Sarah Phillips; Mark Pitt; Benard Poelker; Tracy Porcelli; Gilles Quemener; Brian Quinn; William Ramsay; Aamer Rauf; Jean-Sebastien Real; Julie Roche; Philip Roos; Gary Rutledge; Jeffery Secrest; Neven Simicevic; G.R. Smith; Damon Spayde; Samuel Stepanyan; Marcy Stutzman; Vincent Sulkosky; Vardan Tadevosyan; Raphael Tieulent; Jacques Van de Wiele; Willem van Oers; Eric Voutier; William Vulcan; G. Warren; S.P. Wells; Steven Williamson; S.A. Wood; Chen Yan; Junho Yun; Valdis Zeps

2005-06-01

We have measured parity-violating asymmetries in elastic electron-proton scattering over the range of momentum transfers 0.12 < Q{sup 2} < 1.0 GeV{sup 2}. These asymmetries, arising from interference of the electromagnetic and neutral weak interactions, are sensitive to strange quark contributions to the currents of the proton. The measurements were made at JLab using a toroidal spectrometer to detect the recoiling protons from a liquid hydrogen target. The results indicate non-zero, Q{sup 2} dependent, strange quark contributions and provide new information beyond that obtained in previous experiments.

Estimating the Transfer Range of Plasmids Encoding Antimicrobial Resistance in a Wastewater Treatment Plant Microbial Community

DEFF Research Database (Denmark)

Li, Liguan; Dechesne, Arnaud; He, Zhiming

2018-01-01

sludge microbial community was challenged in standardized filter matings with one of three multidrug resistance plasmids (pKJK5, pB10, and RP4) harbored by Escherichia coli or Pseudomonas putida. Different donor–plasmid combinations had distinct transfer frequencies, ranging from 3 to 50 conjugation...... events per 100000 cells of the WWTP microbial community. In addition, transfer was observed to a broad phylogenetic range of 13 bacterial phyla with several taxa containing potentially pathogenic species. Preferential transfer to taxa belonging to the predicted evolutionary host range of the plasmids...... ARG transmission. However, the contribution of microbial communities in WWTPs to ARG dissemination remains poorly understood. Here, we examined for the first time plasmid permissiveness of an activated sludge microbial community by utilizing an established fluorescent bioreporter system. The activated...

Miedema model based methodology to predict amorphous-forming-composition range in binary and ternary systems

Energy Technology Data Exchange (ETDEWEB)

Das, N., E-mail: nirupamd@barc.gov.in [Materials Science Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085 (India); Mittra, J. [Materials Science Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085 (India); Murty, B.S. [Department of Metallurgical and Materials Engineering, IIT Madras, Chennai 600 036 (India); Pabi, S.K. [Department of Metallurgical and Materials Engineering, IIT Kharagpur, Kharagpur 721 302 (India); Kulkarni, U.D.; Dey, G.K. [Materials Science Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085 (India)

2013-02-15

Highlights: Black-Right-Pointing-Pointer A methodology was proposed to predict amorphous forming compositions (AFCs). Black-Right-Pointing-Pointer Chemical contribution to enthalpy of mixing {proportional_to} enthalpy of amorphous for AFCs. Black-Right-Pointing-Pointer Accuracy in the prediction of AFC-range was noticed in Al-Ni-Ti system. Black-Right-Pointing-Pointer Mechanical alloying (MA) results of Al-Ni-Ti followed the predicted AFC-range. Black-Right-Pointing-Pointer Earlier MA results of Al-Ni-Ti also conformed to the predicted AFC-range. - Abstract: From the earlier works on the prediction of amorphous forming composition range (AFCR) using Miedema based model and also, on mechanical alloying experiments it has been observed that all amorphous forming compositions of a given alloy system falls within a linear band when the chemical contribution to enthalpy of the solid solution ({Delta}H{sup ss}) is plotted against the enthalpy of mixing in the amorphous phase ({Delta}H{sup amor}). On the basis of this observation, a methodology has been proposed in this article to identify the AFCR of a ternary system that is likely to be more precise than what can be obtained using {Delta}H{sup amor} - {Delta}H{sup ss} < 0 criterion. MA experiments on various compositions of Al-Ni-Ti system, producing amorphous, crystalline, and mixture of amorphous plus crystalline phases have been carried out and the phases have been characterized using X-ray diffraction and transmission electron microscopy techniques. Data from the present MA experiments and, also, from the literature have been used to validate the proposed approach. Also, the proximity of compositions, producing a mixture of amorphous and crystalline phases to the boundary of AFCR in the Al-Ni-Ti ternary has been found useful to validate the effectiveness of the prediction.

A quorum sensing-mediated switch contributes to natural transformation of Vibrio cholerae

OpenAIRE

Blokesch Melanie

2013-01-01

There is a fundamental gap in our understanding of how horizontal gene transfer contributes to the enormous range of genetic variations that are observed among bacteria. The objective of our study was to better understand how the acquisition of genetic material by natural transformation is regulated within a population of Vibrio cholerae cells. V. cholerae is an aquatic bacterium and a facultative human pathogen. It acquires natural competence for transformation in response to changing enviro...

Introducing and modeling inefficiency contributions

DEFF Research Database (Denmark)

Asmild, Mette; Kronborg, Dorte; Matthews, Kent

2016-01-01

-called inefficiency contributions, which are defined as the relative contributions from specific variables to the overall levels of inefficiencies. A statistical model for distinguishing the inefficiency contributions between subgroups is proposed and the method is illustrated on a data set on Chinese banks....

Catchment source contributions to the sediment-bound organic matter degrading salmonid spawning gravels in a lowland river, southern England

Energy Technology Data Exchange (ETDEWEB)

Collins, A.L., E-mail: adrian.collins@adas.co.uk [ADAS, Pendeford House, Wobaston Road, Wolverhampton WV9 5AP (United Kingdom); Geography and Environment, University of Southampton, Highfield, Southampton SO17 1BJ (United Kingdom); Williams, L.J.; Zhang, Y.S. [ADAS, Pendeford House, Wobaston Road, Wolverhampton WV9 5AP (United Kingdom); Marius, M. [Civil Engineering and Environment, University of Southampton, Highfield, Southampton S017 1BJ (United Kingdom); Dungait, J.A.J. [Department of Sustainable Systems and Grassland Science, Rothamsted Research—North Wyke, Okehampton, Devon EX20 2SB (United Kingdom); Smallman, D.J. [Civil Engineering and Environment, University of Southampton, Highfield, Southampton S017 1BJ (United Kingdom); Dixon, E.R. [Department of Sustainable Systems and Grassland Science, Rothamsted Research—North Wyke, Okehampton, Devon EX20 2SB (United Kingdom); Stringfellow, A. [Civil Engineering and Environment, University of Southampton, Highfield, Southampton S017 1BJ (United Kingdom); Sear, D.A. [Geography and Environment, University of Southampton, Highfield, Southampton SO17 1BJ (United Kingdom); Jones, J.I. [School of Biological and Chemical Sciences, Queen Mary University of London, Mile End Road, London, E1 4NS (United Kingdom); Naden, P.S. [CEH Wallingford, Maclean Building, Benson Lane, Crowmarsh Gifford, Wallingford, Oxfordshire, OX10 8BB (United Kingdom)

2013-07-01

The ingress of particulate material into freshwater spawning substrates is thought to be contributing to the declining success of salmonids reported over recent years for many rivers. Accordingly, the need for reliable information on the key sources of the sediment problem has progressed up the management agenda. Whilst previous work has focussed on apportioning the sources of minerogenic fine sediment degrading spawning habitats, there remains a need to develop procedures for generating corresponding information for the potentially harmful sediment-bound organic matter that represents an overlooked component of interstitial sediment. A source tracing procedure based on composite signatures combining bulk stable {sup 13}C and {sup 15}N isotope values with organic molecular structures detected using near infrared (NIR) reflectance spectroscopy was therefore used to assess the primary sources of sediment-bound organic matter sampled from artificial spawning redds. Composite signatures were selected using a combination of the Kruskal–Wallis H-test, principal component analysis and GA-driven discriminant function analysis. Interstitial sediment samples were collected using time-integrating basket traps which were inserted at the start of the salmonid spawning season and extracted in conjunction with critical phases of fish development (eyeing, hatch, emergence, late spawning). Over the duration of these four basket extractions, the overall relative frequency-weighted average median (± 95% confidence limits) source contributions to the interstitial sediment-bound organic matter were estimated to be in the order: instream decaying vegetation (39 ± < 1%; full range 0–77%); damaged road verges (28 ± < 1%; full range 0–77%); septic tanks (22 ± < 1%; full range 0–50%), and; farm yard manures/slurries (11 ± < 1%; full range 0–61%). The reported procedure provides a promising basis for understanding the key sources of interstitial sediment-bound organic matter

Magnetic susceptibility as a method of investigation of short-range order in strongly nonstoichiometric carbides

International Nuclear Information System (INIS)

Nazarova, S.Z.; Gusev, A.I.

2001-01-01

Magnetic susceptibility in disordered and ordered carbides of transition metals (M = Ti, Zr, Hf, Nb, Ta) was studied, the results are generalized. It was ascertained that the change in carbide susceptibility induced by deviation from stoichiometry stems from specific features of electronic spectra of the compounds. The use of magnetic susceptibility for determining structural disorder-order transitions is discussed. It is shown that change in the contribution made by orbital paramagnetism, resulting from short-range order formation, is the reason of decrease in susceptibility of nonstoichiometric carbides during the ordering. Experimentally obtained data on susceptibility permitted evaluating short- and far-range order parameters in NbC y , TaC y , TiC y and HfC y carbides [ru

Recycling of paper: accounting of greenhouse gases and global warming contributions.

Science.gov (United States)

Merrild, Hanna; Damgaard, Anders; Christensen, Thomas H

2009-11-01

Greenhouse gas (GHG) emissions have been established for recycling of paper waste with focus on a material recovery facility (MRF). The MRF upgrades the paper and cardboard waste before it is delivered to other industries where new paper or board products are produced. The accounting showed that the GHG contributions from the upstream activities and operational activities, with global warming factors (GWFs) of respectively 1 to 29 and 3 to 9 kg CO(2)-eq. tonne(- 1) paper waste, were small in comparison wih the downstream activities. The GHG contributions from the downstream reprocessing of the paper waste ranged from approximately 490 to 1460 kg CO(2)-eq. tonne( -1) of paper waste. The system may be expanded to include crediting of avoided virgin paper production which would result in GHG contributions from -1270 to 390 kg CO(2)-eq. tonne(- 1) paper waste. It may also be assumed that the wood not used for virgin paper production instead is used for production of energy that in turn is assumed to substitute for fossil fuel energy. This would result in GHG contributions from -1850 to -4400 kg CO(2)-eq. tonne(- 1) of paper waste. These system expansions reveal very large GHG savings, suggesting that the indirect upstream and operational GHG contributions are negligible in comparison with the indirect downstream emissions. However, the data for reprocessing of paper waste and the data for virgin paper production are highly variable. These differences are mainly related to different energy sources for the mills, both in regards to energy form (heat or electricity) and fuel (biomass or fossil fuels).

Contribution of Food Groups to Energy and Nutrient Intakes in Five Developed Countries

Directory of Open Access Journals (Sweden)

Nancy Auestad

2015-06-01

Full Text Available Economic growth in developing countries and globalization of the food sector is leading to increasingly similar food consumption patterns worldwide. The aim of this study was to describe similarities and differences in the contributions of main food groups to energy and nutrient intakes in five developed countries across three continents. We obtained summary reports of national food consumption survey data from Australia, France, Denmark, the Netherlands, and the United States. Survey years spanned 2003–2012; sample size ranged from 1444 to 17,386. To mitigate heterogeneity of food groups across countries, we recategorized each survey’s reported food groups and subgroups into eight main food groups and, for three countries, a ninth “mixed dishes” group. We determined the percent contribution of each food group to mean daily intakes of energy, saturated fat, sodium, fiber, and ten vitamins and minerals that are commonly under-consumed. Differences in findings from surveys utilizing a foods-as-consumed versus a disaggregated or ingredients approach to food group composition and contributions from the milk and milk products group, a source of several under-consumed nutrients, were explored. Patterns of food group contributions to energy and nutrient intakes were generally similar across countries. Some differences were attributable to the analytical approach used by the surveys. For the meat/protein, milk and milk products, vegetables, and fruit groups, percent contributions to key nutrient intakes exceeded percent contributions to energy intake. The mixed dishes group provided 10%–20% of total daily energy and a similar 10%–25% of the daily intake of several nutrients. This descriptive study contributes to an understanding of food group consumption patterns in developed countries.

Contribution of Food Groups to Energy and Nutrient Intakes in Five Developed Countries

Science.gov (United States)

Auestad, Nancy; Hurley, Judith S.; Fulgoni, Victor L.; Schweitzer, Cindy M.

2015-01-01

Economic growth in developing countries and globalization of the food sector is leading to increasingly similar food consumption patterns worldwide. The aim of this study was to describe similarities and differences in the contributions of main food groups to energy and nutrient intakes in five developed countries across three continents. We obtained summary reports of national food consumption survey data from Australia, France, Denmark, the Netherlands, and the United States. Survey years spanned 2003–2012; sample size ranged from 1444 to 17,386. To mitigate heterogeneity of food groups across countries, we recategorized each survey’s reported food groups and subgroups into eight main food groups and, for three countries, a ninth “mixed dishes” group. We determined the percent contribution of each food group to mean daily intakes of energy, saturated fat, sodium, fiber, and ten vitamins and minerals that are commonly under-consumed. Differences in findings from surveys utilizing a foods-as-consumed versus a disaggregated or ingredients approach to food group composition and contributions from the milk and milk products group, a source of several under-consumed nutrients, were explored. Patterns of food group contributions to energy and nutrient intakes were generally similar across countries. Some differences were attributable to the analytical approach used by the surveys. For the meat/protein, milk and milk products, vegetables, and fruit groups, percent contributions to key nutrient intakes exceeded percent contributions to energy intake. The mixed dishes group provided 10%–20% of total daily energy and a similar 10%–25% of the daily intake of several nutrients. This descriptive study contributes to an understanding of food group consumption patterns in developed countries. PMID:26061017

45 CFR 1326.9 - Contributions.

Science.gov (United States)

2010-10-01

... INDIAN TRIBES FOR SUPPORT AND NUTRITION SERVICES § 1326.9 Contributions. (a) Each tribal organization... contributions to expand comprehensive and coordinated services systems supported under this part, while using nutrition services contributions only to expand services as provided under section 307(a)(13)(c)(ii) of the...

Variability of Diurnal Temperature Range During Winter Over Western Himalaya: Range- and Altitude-Wise Study

Science.gov (United States)

Shekhar, M. S.; Devi, Usha; Dash, S. K.; Singh, G. P.; Singh, Amreek

2018-04-01

The current trends in diurnal temperature range, maximum temperature, minimum temperature, mean temperature, and sun shine hours over different ranges and altitudes of Western Himalaya during winter have been studied. Analysis of 25 years of data shows an increasing trend in diurnal temperature range over all the ranges and altitudes of Western Himalaya during winter, thereby confirming regional warming of the region due to present climate change and global warming. Statistical studies show significant increasing trend in maximum temperature over all the ranges and altitudes of Western Himalaya. Minimum temperature shows significant decreasing trend over Pir Panjal and Shamshawari range and significant increasing trend over higher altitude of Western Himalaya. Similarly, sunshine hours show significant decreasing trend over Karakoram range. There exists strong positive correlation between diurnal temperature range and maximum temperature for all the ranges and altitudes of Western Himalaya. Strong negative correlation exists between diurnal temperature range and minimum temperature over Shamshawari and Great Himalaya range and lower altitude of Western Himalaya. Sunshine hours show strong positive correlation with diurnal temperature range over Pir Panjal and Great Himalaya range and lower and higher altitudes.

Climate driven range divergence among host species affects range-wide patterns of parasitism

Directory of Open Access Journals (Sweden)

Richard E. Feldman

2017-01-01

Full Text Available Species interactions like parasitism influence the outcome of climate-driven shifts in species ranges. For some host species, parasitism can only occur in that part of its range that overlaps with a second host species. Thus, predicting future parasitism may depend on how the ranges of the two hosts change in relation to each other. In this study, we tested whether the climate driven species range shift of Odocoileus virginianus (white-tailed deer accounts for predicted changes in parasitism of two other species from the family Cervidae, Alces alces (moose and Rangifer tarandus (caribou, in North America. We used MaxEnt models to predict the recent (2000 and future (2050 ranges (probabilities of occurrence of the cervids and a parasite Parelaphostrongylus tenuis (brainworm taking into account range shifts of the parasite’s intermediate gastropod hosts. Our models predicted that range overlap between A. alces/R. tarandus and P. tenuis will decrease between 2000 and 2050, an outcome that reflects decreased overlap between A. alces/R. tarandus and O. virginianus and not the parasites, themselves. Geographically, our models predicted increasing potential occurrence of P. tenuis where A. alces/R. tarandus are likely to decline, but minimal spatial overlap where A. alces/R. tarandus are likely to increase. Thus, parasitism may exacerbate climate-mediated southern contraction of A. alces and R. tarandus ranges but will have limited influence on northward range expansion. Our results suggest that the spatial dynamics of one host species may be the driving force behind future rates of parasitism for another host species.

Short-range fundamental forces

International Nuclear Information System (INIS)

Antoniadis, I.; Baessler, S.; Buchner, M.; Fedorov, V.V.; Hoedl, S.; Nesvizhevsky, V.V.; Pignol, G.; Protasov, K.V.; Lambrecht, A.; Reynaud, S.; Sobolev, Y.

2010-01-01

We consider theoretical motivations to search for extra short-range fundamental forces as well as experiments constraining their parameters. The forces could be of two types: 1) spin-independent forces; 2) spin-dependent axion-like forces. Different experimental techniques are sensitive in respective ranges of characteristic distances. The techniques include measurements of gravity at short distances, searches for extra interactions on top of the Casimir force, precision atomic and neutron experiments. We focus on neutron constraints, thus the range of characteristic distances considered here corresponds to the range accessible for neutron experiments

COP 21: the national contributions

International Nuclear Information System (INIS)

Jouette, Isabelle

2015-01-01

This article comments the content of the national contributions (the so-called Intended Nationally Determined Contributions or INDC) which every country should have transmitted to the UN before the COP 21. In fact, 148 contributions, i.e. 75 per cent of the expected ones, have been transmitted. The author recalls that the content of these contributions had to obey some principles which had been defined in Lima in 2014, and that each country must identify its objectives in terms of mitigation (reduction of greenhouse gas emissions) and adaptation (reduction of the vulnerability of natural and human systems). The author comments some specific commitments regarding climate, emission reduction, adaptation to climate change, and more particularly evokes the Ethiopian contribution which is considered as exemplary

Long range transport of fine particle windblown soils and coal fired power station emissions into Hanoi between 2001 to 2008

Energy Technology Data Exchange (ETDEWEB)

Cohen, D.D.; Crawford, J.; Stelcer, E.; Vuong, T.B. [Australian Nuclear Science & Technology Organisation, Kirrawee DC, NSW (Australia)

2010-10-15

Fine particulate matter (PM2.5), source fingerprints and their contributions have been measured and reported previously at Hanoi, Vietnam, from 25 April 2001 to 31 December 2008. In this study back trajectories are used to identify long range transport into Hanoi for two of these sources, namely, windblown dust (Soil) from 12 major deserts in China and emissions from 33 coal fired power plants (Coal) in Vietnam and China. There were 28 days of extreme Soil events with concentrations greater than 6 {mu} g m{sup -3} and 25 days of extreme Coal with concentrations greater than 30 {mu} g m{sup -3} from a total of 748 sampling days during the study period. Through the use of back trajectories it was found that long range transport of soil from the Taklamakan and Gobi desert regions (more than 3000 km to the north west) accounted for 76% of the extreme events for Soil. The three local Vietnamese power stations contributed to 15% of the extreme Coal events, while four Chinese power stations between 300 km and 1700 km to the north-east of Hanoi contributed 50% of the total extreme Coal events measured at the Hanoi sampling site.

Soliton microcomb range measurement

Science.gov (United States)

Suh, Myoung-Gyun; Vahala, Kerry J.

2018-02-01

Laser-based range measurement systems are important in many application areas, including autonomous vehicles, robotics, manufacturing, formation flying of satellites, and basic science. Coherent laser ranging systems using dual-frequency combs provide an unprecedented combination of long range, high precision, and fast update rate. We report dual-comb distance measurement using chip-based soliton microcombs. A single pump laser was used to generate dual-frequency combs within a single microresonator as counterpropagating solitons. We demonstrated time-of-flight measurement with 200-nanometer precision at an averaging time of 500 milliseconds within a range ambiguity of 16 millimeters. Measurements at distances up to 25 meters with much lower precision were also performed. Our chip-based source is an important step toward miniature dual-comb laser ranging systems that are suitable for photonic integration.

Total nuclear photoabsorption cross section in the range 0.2-1.0 GeV for nuclei throughout the periodic table

International Nuclear Information System (INIS)

Terranova, M.L.; Tavares, O.A.P.

1994-01-01

An analysis of the total photoabsorption cross section for nuclei ranging from 4 He up to 238 U has been performed in the energy range 0.2-1.0 GeV. Mean total photoabsorption cross sections have been obtained by summing up the contributions from partial photoreactions, and found to follow an A 1 -dependence in the 0.2-1.0 GeV range. A review of the available total photoabsorption cross section data is also presented. Comparisons have been made with cross section values calculated by considering both the quasi-deuteron and π-meson photoproduction mechanism of primary nuclear photointeraction. (orig.)

Climate contributes to zonal forest mortality in Southern California's San Jacinto Mountains

Science.gov (United States)

Fellows, A.; Goulden, M.

2010-12-01

An estimated 4.6 million trees died over ~375,000 acres of Southern California forest in 2002-2004. This mortality punctuated a decline in forest health that has been attributed to air pollution, stem densification, or drought. Bark beetles were the proximate cause of most tree death but the underlying cause of this extensive mortality is arguably poor forest health. We investigated the contributions that climate, particularly drought, played in tree mortality and how physiological drought stress may have structured the observed patterns of mortality. Field surveys showed that conifer mortality was zonal in the San Jacinto Mountains of Southern California. The proportion of conifer mortality increased with decreasing elevation (p=0.01). Mid-elevation conifers (White Fir, Incense Cedar, Coulter Pine, Sugar Pine, Ponderosa and Jeffrey Pine) died in the lower portions of their respective ranges, which resulted in an upslope lean in species’ distribution and an upslope shift in species’ mean elevation. Long-term precipitation (P) is consistent with elevation over the conifer elevation range (p=0.43). Potential evapotranspiration (ET) estimated by Penman Monteith declines with elevation by nearly half over the same range. These trends suggest that ET, more than P, is critical in structuring the elevational trend in drought stress and may have contributed to the patterns of mortality that occurred in 2002-04. Physiological measurements in a mild drought year (2009) showed late summer declines in plant water availability with decreasing elevation (p < 0.01) and concomitant reductions in carbon assimilation and stomatal conductance with decreasing elevation. We tie these observations together with a simple water balance model.

Low susceptibility of invasive red lionfish (Pterois volitans to a generalist ectoparasite in both its introduced and native ranges.

Directory of Open Access Journals (Sweden)

Paul C Sikkel

Full Text Available Escape from parasites in their native range is one of many mechanisms that can contribute to the success of an invasive species. Gnathiid isopods are blood-feeding ectoparasites that infest a wide range of fish hosts, mostly in coral reef habitats. They are ecologically similar to terrestrial ticks, with the ability to transmit blood-borne parasites and cause damage or even death to heavily infected hosts. Therefore, being highly resistant or highly susceptible to gnathiids can have significant fitness consequences for reef-associated fishes. Indo-Pacific red lionfish (Pterois volitans have invaded coastal habitats of the western tropical and subtropical Atlantic and Caribbean regions. We assessed the susceptibility of red lionfish to parasitic gnathiid isopods in both their native Pacific and introduced Atlantic ranges via experimental field studies during which lionfish and other, ecologically-similar reef fishes were caged and exposed to gnathiid infestation on shallow coral reefs. Lionfish in both ranges had very few gnathiids when compared with other species, suggesting that lionfish are not highly susceptible to infestation by generalist ectoparasitic gnathiids. While this pattern implies that release from gnathiid infestation is unlikely to contribute to the success of lionfish as invaders, it does suggest that in environments with high gnathiid densities, lionfish may have an advantage over species that are more susceptible to gnathiids. Also, because lionfish are not completely resistant to gnathiids, our results suggest that lionfish could possibly have transported blood parasites between their native Pacific and invaded Atlantic ranges.

Contribution of regional-scale fire events to ozone and PM2.5 ...

Science.gov (United States)

Two specific fires from 2011 are tracked for local to regional scale contribution to ozone (O3) and fine particulate matter (PM2.5) using a freely available regulatory modeling system that includes the BlueSky wildland fire emissions tool, Spare Matrix Operator Kernel Emissions (SMOKE) model, Weather and Research Forecasting (WRF) meteorological model, and Community Multiscale Air Quality (CMAQ) photochemical grid model. The modeling system was applied to track the contribution from a wildfire (Wallow) and prescribed fire (Flint Hills) using both source sensitivity and source apportionment approaches. The model estimated fire contribution to primary and secondary pollutants are comparable using source sensitivity (brute-force zero out) and source apportionment (Integrated Source Apportionment Method) approaches. Model estimated O3 enhancement relative to CO is similar to values reported in literature indicating the modeling system captures the range of O3 inhibition possible near fires and O3 production both near the fire and downwind. O3 and peroxyacetyl nitrate (PAN) are formed in the fire plume and transported downwind along with highly reactive VOC species such as formaldehyde and acetaldehyde that are both emitted by the fire and rapidly produced in the fire plume by VOC oxidation reactions. PAN and aldehydes contribute to continued downwind O3 production. The transport and thermal decomposition of PAN to nitrogen oxides (NOX) enables O3 production in areas

Sampling Number Effects in 2D and Range Imaging of Range-gated Acquisition

International Nuclear Information System (INIS)

Kwon, Seong-Ouk; Park, Seung-Kyu; Baik, Sung-Hoon; Cho, Jai-Wan; Jeong, Kyung-Min

2015-01-01

In this paper, we analyzed the number effects of sampling images for making a 2D image and a range image from acquired RGI images. We analyzed the number effects of RGI images for making a 2D image and a range image using a RGI vision system. As the results, 2D image quality was not much depended on the number of sampling images but on how much well extract efficient RGI images. But, the number of RGI images was important for making a range image because range image quality was proportional to the number of RGI images. Image acquiring in a monitoring area of nuclear industry is an important function for safety inspection and preparing appropriate control plans. To overcome the non-visualization problem caused by airborne obstacle particles, vision systems should have extra-functions, such as active illumination lightening through disturbance airborne particles. One of these powerful active vision systems is a range-gated imaging system. The vision system based on the range-gated imaging system can acquire image data from raining or smoking environments. Range-gated imaging (RGI) is a direct active visualization technique using a highly sensitive image sensor and a high intensity illuminant. Currently, the range-gated imaging technique providing 2D and 3D images is one of emerging active vision technologies. The range-gated imaging system gets vision information by summing time sliced vision images. In the RGI system, a high intensity illuminant illuminates for ultra-short time and a highly sensitive image sensor is gated by ultra-short exposure time to only get the illumination light. Here, the illuminant illuminates objects by flashing strong light through airborne disturbance particles. Thus, in contrast to passive conventional vision systems, the RGI active vision technology robust for low-visibility environments

Sampling Number Effects in 2D and Range Imaging of Range-gated Acquisition

Energy Technology Data Exchange (ETDEWEB)

Kwon, Seong-Ouk; Park, Seung-Kyu; Baik, Sung-Hoon; Cho, Jai-Wan; Jeong, Kyung-Min [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2015-10-15

In this paper, we analyzed the number effects of sampling images for making a 2D image and a range image from acquired RGI images. We analyzed the number effects of RGI images for making a 2D image and a range image using a RGI vision system. As the results, 2D image quality was not much depended on the number of sampling images but on how much well extract efficient RGI images. But, the number of RGI images was important for making a range image because range image quality was proportional to the number of RGI images. Image acquiring in a monitoring area of nuclear industry is an important function for safety inspection and preparing appropriate control plans. To overcome the non-visualization problem caused by airborne obstacle particles, vision systems should have extra-functions, such as active illumination lightening through disturbance airborne particles. One of these powerful active vision systems is a range-gated imaging system. The vision system based on the range-gated imaging system can acquire image data from raining or smoking environments. Range-gated imaging (RGI) is a direct active visualization technique using a highly sensitive image sensor and a high intensity illuminant. Currently, the range-gated imaging technique providing 2D and 3D images is one of emerging active vision technologies. The range-gated imaging system gets vision information by summing time sliced vision images. In the RGI system, a high intensity illuminant illuminates for ultra-short time and a highly sensitive image sensor is gated by ultra-short exposure time to only get the illumination light. Here, the illuminant illuminates objects by flashing strong light through airborne disturbance particles. Thus, in contrast to passive conventional vision systems, the RGI active vision technology robust for low-visibility environments.

Range-energy relations and stopping power of water, water vapour and tissue equivalent liquid for α particles over the energy range 0.5 to 8 MeV

International Nuclear Information System (INIS)

Palmer, R.B.J.; Akhavan-Rezayat, Ahmad

1978-01-01

Experimental range-energy relations are presented for alpha particles in water, water vapour and tissue equivalent liquid at energies up to 8 MeV. From these relations differential stopping powers are derived at 0.25 MeV energy intervals. Consideration is given to sources of error in the range-energy measurements and to the uncertainties that these will introduce into the stopping power values. The ratio of the differential stopping power of muscle equivalent liquid to that of water over the energy range 0.5 to 7.5 MeV is discussed in relation to the specific gravity and chemical composition of the muscle equivalent liquid. Theoretical molecular stopping power calculations based upon the Bethe formula are also presented for water. The effect of phase upon the stopping power of water is discussed. The molecular stopping power of water vapour is shown to be significantly higher than that of water for energies below 1.25 MeV and above 2.5 MeV, the ratio of the two stopping powers rising to 1.39 at 0.5 MeV and to 1.13 at 7.0 MeV. Stopping power measurements for other liquids and vapours are compared with the results for water and water vapour and some are observed to have stopping power ratios in the vapour and liquid phases which vary with energy in a similar way to water. It is suggested that there may be several factors contributing to the increased stopping power of liquids. The need for further experimental results on a wider range of liquids is stressed

Contribution of transformation products towards the total herbicide toxicity to tropical marine organisms.

Science.gov (United States)

Mercurio, Philip; Eaglesham, Geoff; Parks, Stephen; Kenway, Matt; Beltran, Victor; Flores, Florita; Mueller, Jochen F; Negri, Andrew P

2018-03-19

The toxicity of herbicide degradation (transformation) products is rarely taken into account, even though these are commonly detected in the marine environment, sometimes at concentrations higher than the parent compounds. Here we assessed the potential contribution of toxicity by transformation products of five photosystem II herbicides to coral symbionts (Symbiodinium sp.), the green algae Dunaliella sp., and prawn (Penaeus monodon) larvae. Concentration-dependent inhibition of photosynthetic efficiency (∆F/F m ') was observed for all herbicides in both microalgal species. The toxicity of solutions of aged diuron solutions containing transformation products to Symbiodinium sp. and Dunaliella sp. was greater than could be explained by the concentrations of diuron measured, indicating transformation products contributed to the inhibition of ∆F/F m '. However, the toxicity of aged atrazine, simazine, hexazinone, and ametryn solutions could be explained by the concentration of parent herbicide, indicating no contribution by transformation products. Prawn larval metamorphosis was not sensitive to the herbicides, but preliminary results indicated some toxicity of the transformation products of atrazine and diuron. Risk assessments should take into account the contribution of herbicide transformation products; however, further studies are clearly needed to test the toxicity of a far wider range of transformation products to a representative diversity of relevant taxa.

Autonomous Target Ranging Techniques

DEFF Research Database (Denmark)

Jørgensen, Peter Siegbjørn; Jørgensen, John Leif; Denver, Troelz

2003-01-01

of this telescope, a fast determination of the range to and the motion of the detected targets are important. This is needed in order to prepare the future observation strategy for each target, i.e. when is the closest approach where imaging will be optimal. In order to quickly obtain such a determination two...... ranging strategies are presented. One is an improved laser ranger with an effective range with non-cooperative targets of at least 10,000 km, demonstrated in ground tests. The accuracy of the laser ranging will be approximately 1 m. The laser ranger may furthermore be used for trajectory determination...... of nano-gravity probes, which will perform direct mass measurements of selected targets. The other is triangulation from two spacecraft. For this method it is important to distinguish between detection and tracking range, which will be different for Bering since different instruments are used...

Pluripotent hybrid cells contribute to extraembryonic as well as embryonic tissues.

Science.gov (United States)

Do, Jeong Tae; Choi, Hyun Woo; Choi, Youngsok; Schöler, Hans R

2011-06-01

The restricted gene expression of a differentiated cell can be reversed by forming hybrid with embryonic stem cells (ESCs). The resulting hybrid cells showed not only an ESC-specific marker expression but also a differentiation potential similar to the pluripotent fusion partner. Here, we evaluated whether the tetraploid fusion hybrid cells have a unique differentiation potential compared with diploid pluripotent cells. The first Oct4-GFP-positive cells were observed at day 2 following fusion between ESCs and neurosphere cells (OG2(+/-)/ROSA26(+/-)). Reprogramming efficiency was as high as 94.5% at passage 5 and 96.4% at passage 13. We have found that the tetraploid hybrid cells could form chimera with contribution to placenta after blastocyst injection. This result indicates that the tetraploid pluripotent fusion hybrid cells have wide range of differentiation potential. Therefore, we suggest that once the somatic cells are reprogrammed by fusion with ESCs, the tetraploid hybrid cells contributed to the extraembryonic as well as embryonic tissues.

Regional contribution to PM1 pollution during winter haze in Yangtze River Delta, China.

Science.gov (United States)

Tang, Lili; Yu, Hongxia; Ding, Aijun; Zhang, Yunjiang; Qin, Wei; Wang, Zhuang; Chen, Wentai; Hua, Yan; Yang, Xiaoxiao

2016-01-15

To quantify regional sources contributing to submicron particulate matter (PM1) pollution in haze episodes, on-line measurements combining two modeling methods, namely, positive matrix factorization (PMF) and backward Lagrangian particle dispersion modeling (LPDM), were conducted for the period of one month in urban Nanjing, a city located in the western part of Yangtze River Delta (YRD) region of China. Several multi-day haze episodes were observed in December 2013. Long-range transport of biomass burning from the southwestern YRD region largely contributed to PM1 pollution with more than 25% of total organics mass in a lasting heavy haze. The LPDM analysis indicates that regional transport is a main source contributing to secondary low-volatility production. The high-potential source regions of secondary low-volatility production are mainly located in areas to the northeast of the city. High aerosol pollution was mainly contributed by regional transport associated with northeastern air masses. Such regional transport on average accounts for 46% of total NR-PM1 with sulfate and aged low-volatility organics being the largest fractions (>65%). Copyright © 2015 Elsevier B.V. All rights reserved.

Effective dose range for dental cone beam computed tomography scanners

International Nuclear Information System (INIS)

Pauwels, Ruben; Beinsberger, Jilke; Collaert, Bruno; Theodorakou, Chrysoula; Rogers, Jessica; Walker, Anne; Cockmartin, Lesley; Bosmans, Hilde; Jacobs, Reinhilde; Bogaerts, Ria; Horner, Keith

2012-01-01

Objective: To estimate the absorbed organ dose and effective dose for a wide range of cone beam computed tomography scanners, using different exposure protocols and geometries. Materials and methods: Two Alderson Radiation Therapy anthropomorphic phantoms were loaded with LiF detectors (TLD-100 and TLD-100H) which were evenly distributed throughout the head and neck, covering all radiosensitive organs. Measurements were performed on 14 CBCT devices: 3D Accuitomo 170, Galileos Comfort, i-CAT Next Generation, Iluma Elite, Kodak 9000 3D, Kodak 9500, NewTom VG, NewTom VGi, Pax-Uni3D, Picasso Trio, ProMax 3D, Scanora 3D, SkyView, Veraviewepocs 3D. Effective dose was calculated using the ICRP 103 (2007) tissue weighting factors. Results: Effective dose ranged between 19 and 368 μSv. The largest contributions to the effective dose were from the remainder tissues (37%), salivary glands (24%), and thyroid gland (21%). For all organs, there was a wide range of measured values apparent, due to differences in exposure factors, diameter and height of the primary beam, and positioning of the beam relative to the radiosensitive organs. Conclusions: The effective dose for different CBCT devices showed a 20-fold range. The results show that a distinction is needed between small-, medium-, and large-field CBCT scanners and protocols, as they are applied to different indication groups, the dose received being strongly related to field size. Furthermore, the dose should always be considered relative to technical and diagnostic image quality, seeing that image quality requirements also differ for patient groups. The results from the current study indicate that the optimisation of dose should be performed by an appropriate selection of exposure parameters and field size, depending on the diagnostic requirements.

The Contributions of the WIYN Observatory to Undergraduate Education

Science.gov (United States)

Hooper, Eric; Consortium, WIYN

2014-01-01

Over its nearly 20 year history the WIYN Observatory has provided crucial data for numerous undergraduate research projects at the partner institutions (University of Wisconsin-Madison, Indiana University, and Yale University) plus others who access the telescope via national time from NOAO. WIYN and its instruments have served both undergraduates who are local to each institution, as well as those who have a temporary tenure as Research Experience for Undergraduates (REU) students. The topics of this work range widely, and only a few examples are listed here. Numerous studies of stars have been undertaken by undergraduates, from rotation velocities of pre-main sequence stars (Rhode et al.) to dynamical heating mechanisms in open clusters (Friel et al.). Extragalactic investigations range from a study of cold ISM in galaxies near the centers of rich clusters (Gallagher & Hooper, et al.) to the stellar populations of post-starburst galaxies hosting low-level AGN (Wolf & Hooper, et al.). Students have made wide use of WIYN's long established suite of facility instruments, which currently includes the Hydra multi-object fiber spectrograph, the SparsePak integral field unit fiber spectrograph, and the WHIRC near-infrared imager. A current undergraduate is a key player in final laboratory testing of two new integral field units that will come to WIYN soon. Finally, the new large format imager pODI currently is in science operation, soon to be followed by an upgrade to nearly four times the current imaging area, a powerful tool that will join the others in contributing to undergraduate research and education. This presentation is a continuation of the overview of WIYN contributions to education that began with a discussion of graduate education at the Indianapolis AAS (Hooper, AAS Meeting #222, #214.23).

Calculation of contribution of multiple interactions and efficiency of neutron detectors

International Nuclear Information System (INIS)

Androsenko, A.A.; Androsenko, P.A.; Kazakov, L.E.; Kononov, V.N.; Poletaev, E.D.

1986-01-01

Results of calculation of multiple neutron interactions contribution to efficiency of detectors with 6 Li glass and 10 B plate in the energy range of 0.01-1 MeV are given. The calculation was performed by the Monte-Carlo method using BRAND program complex. It is shown that a correction value for multiple neutron interaction in 6 Li glass of 1 mm thickness constitutes 4.5 % at energy of up to 100 keV and at higher energies has a complex energy dependence reaching 25 % at 440 keV

58. annual symposium of the Austrian Physical Society. Conference programme

International Nuclear Information System (INIS)

Oswald, J.

2008-01-01

Full text: This annual conference consisted of a plenary session, oral and poster sessions on the research fields of: acoustics; atoms, quantum optics and plasma (doped helium droplets, biomolecules studies in super fluid helium droplets, quantum physics with neutrons); solid state physics (terahertz quantum-cascade lasers, semiconductors nanostructures, magnetic studies on steel pipeline tubes, magnetic characterization magnetic materials, spin properties of confined electrons); physics history; nuclear and particle physics (antiprotonic helium - hyperfine structure, pionic atoms (hydrogen), CMS experiment at LHC (level 1-trigger, super symmetry), vertex reconstruction toolkit RAVE, silicon strip detectors, chiral transition temperature, quantum physics - Bell theorem, Bethe-Salpeter equation, plane static magnetic field, low-lying eigen modes of the dirac operator, SU(3) potentials by thick-center-vortex-model); medical, bio - and environmental physics; neutrons and synchrotron radiation physics (neutron holography - advances, atomic diffusion by XPCS, micro-diffraction experiments, cold three-axis spectrometer - next generation, superconductive radio resonating cavities- roughness, neutron polarization); surfaces and thin films (carbon monoxide adsorption on metal surfaces, laser - assisted deposition, nanostructures (magnetic properties, semiconductors, electronic structure, erosion, crystal growth, adsorption, sputtering)); physics - industry - energy; besides a poster session on polymer physics and the Max Auwaerter symposium are included. Those contributions which are in the INIS subject scope are indexed individually. (nevyjel)

Control practices contribute to premature transformer failures

Energy Technology Data Exchange (ETDEWEB)

Jauch, E.T. [Beckwith Electric Company Inc., Largo, FL (United States)

2007-07-01

Studies of premature load tap changer (LTC) transformer failures on utility systems have shown the tap changers to be the primary contributing factor. Some of the LTC factors that lead to transformer failures include oil quality and particulate contamination; LTC contact temperature rise; contact coking; carbon film build-up; short circuit mechanical forces; and contact wear and arcing. These factors create increasing contact resistance thereby increasing voltage drop, localized heating, contact pitting, oil contamination and general deterioration. This paper discussed utility tapchanger control practices and methods of determining control functions to be activated as well as the determination of optimum settings contributing to excessive or untimely tap change operations. The transformer applications that were considered included transmission tie transformers as well as transmission distribution interface transformers. The paper discussed the circulating current paralleling method and the circulating reactive current or var sharing paralleling method. Several common practices were discussed, including basic voltage control ranges and setting effects; timing options available; LDC misapplications; first house protection methods; and various paralleling techniques. It was concluded that although there are several other methods of paralleling power transformers, many are not applicable under certain system configurations. In these applications, improper use of a paralleling method or improper setting and commissioning may cause hunting for appropriate tap positions and dramatically increase the number of tap changes, causing wear and degradation of the tap changer contacts. 3 refs., 5 figs.

Japanese contributions to IAEA INTOR workshop, phase two A, part 2, chapter IV: RF heating and current drive

International Nuclear Information System (INIS)

Sugihara, Masayoshi; Kimura, Haruyuki; Okazaki, Takashi

1985-07-01

This report corresponds to Chapter IV of Japanese contribution report to IAEA INTOR Workshop, phase Two A, Part 2. Data base assessments of plasma heating and launcher system design for Ion Cyclotron Range of Frequency (ICRF) wave, for Lower Hybrid Range of Frequency (LHRF) wave, and for Electron Cyclotron Range of Frequency (ECRF) wave are made. Assessments of current drive by LHRF, and of start-up assist and profile control by ECRF are also made. R and D programmes both physics and technology for each of the waves are specified. Applications of these waves to INTOR are examined. (author)

Range Selection and Median

DEFF Research Database (Denmark)

Jørgensen, Allan Grønlund; Larsen, Kasper Green

2011-01-01

and several natural special cases thereof. The rst special case is known as range median, which arises when k is xed to b(j 􀀀 i + 1)=2c. The second case, denoted prex selection, arises when i is xed to 0. Finally, we also consider the bounded rank prex selection problem and the xed rank range......Range selection is the problem of preprocessing an input array A of n unique integers, such that given a query (i; j; k), one can report the k'th smallest integer in the subarray A[i];A[i+1]; : : : ;A[j]. In this paper we consider static data structures in the word-RAM for range selection...... selection problem. In the former, data structures must support prex selection queries under the assumption that k for some value n given at construction time, while in the latter, data structures must support range selection queries where k is xed beforehand for all queries. We prove cell probe lower bounds...

Underwater Ranging

OpenAIRE

S. P. Gaba

1984-01-01

The paper deals with underwater laser ranging system, its principle of operation and maximum depth capability. The sources of external noise and methods to improve signal-to-noise ratio are also discussed.

Pionic corrections to the MIT bag model: The (3,3) resonance

International Nuclear Information System (INIS)

Theberge, S.; Thomas, A.W.; Miller, G.A.

1980-01-01

By incorporating chiral invariance in the MIT bag model, we are led to a theory in which the pion field is coupled to the confined quarks only at the bag surface. An equivalent quantized theory of nucleons and Δ's interacting with pions is then obtained. The pion-nucleon scattering amplitude in this model is found to give a good fit to experimental data on the (3,3) resonance, with a bag radius of about 0.72 fm

Contribution of geodiversity, climate and spatial variables for biodiversity across a gradient of human influence

Science.gov (United States)

Tukiainen, Helena; Alahuhta, Janne; Ala-Hulkko, Terhi; Field, Richard; Lampinen, Raino; Hjort, Jan

2016-04-01

Implementation of geodiversity may provide new perspectives for nature conservation. The relation between geodiversity and biodiversity has been established in recent studies but remains underexplored in environments with high human pressure. In this study, we explored the effect of geodiversity (i.e. geological, hydrological and geomorphological diversity), climate and spatial variables on biodiversity (vascular plant species richness) in environments with different human impact. The study area ranged trough the boreal vegetation zone in Finland and included altogether 1401 1-km2 grid cells from urban, rural and natural environments. The contribution of environmental variable groups for species diversity in different environments was statistically analyzed with variation partitioning method. According to the results, the contribution of geodiversity decreased and the contribution of climate and spatial variables increased as the land use became more human-induced. Hence, the connection between geodiversity and species richness was most pronounced in natural state environments.

Analysis of the effects of wing interference on the tail contributions to the rolling derivatives

Science.gov (United States)

Michael, William H , Jr

1952-01-01

An analysis of the effects of wing interference on the tail contributions to the rolling stability derivatives of complete airplane configurations is made by calculating the angularity of the air stream at the vertical tail due to rolling and determining the resulting forces and moments. Some of the important factors which affect the resultant angularity on the vertical tail are wing aspect ratio and sweepback, vertical-tail span, and considerations associated with angle of attack and airplane geometry. Some calculated sidewash results for a limited range of plan forms and vertical-tail sizes are presented. Equations taking into account the sidewash results are given for determining the tail contributions to the rolling derivatives. Comparisons of estimated and experimental results indicate that a consideration of wing interference effects improves the estimated values of the tail contributions to the rolling derivatives and that fair agreement with available experimental data is obtained.

In-flight sleep, pilot fatigue and Psychomotor Vigilance Task performance on ultra-long range versus long range flights.

Science.gov (United States)

Gander, Philippa H; Signal, T Leigh; van den Berg, Margo J; Mulrine, Hannah M; Jay, Sarah M; Jim Mangie, Captain

2013-12-01

This study evaluated whether pilot fatigue was greater on ultra-long range (ULR) trips (flights >16 h on 10% of trips in a 90-day period) than on long range (LR) trips. The within-subjects design controlled for crew complement, pattern of in-flight breaks, flight direction and departure time. Thirty male Captains (mean age = 54.5 years) and 40 male First officers (mean age = 48.0 years) were monitored on commercial passenger flights (Boeing 777 aircraft). Sleep was monitored (actigraphy, duty/sleep diaries) from 3 days before the first study trip to 3 days after the second study trip. Karolinska Sleepiness Scale, Samn-Perelli fatigue ratings and a 5-min Psychomotor Vigilance Task were completed before, during and after every flight. Total sleep in the 24 h before outbound flights and before inbound flights after 2-day layovers was comparable for ULR and LR flights. All pilots slept on all flights. For each additional hour of flight time, they obtained an estimated additional 12.3 min of sleep. Estimated mean total sleep was longer on ULR flights (3 h 53 min) than LR flights (3 h 15 min; P(F) = 0.0004). Sleepiness ratings were lower and mean reaction speed was faster at the end of ULR flights. Findings suggest that additional in-flight sleep mitigated fatigue effectively on longer flights. Further research is needed to clarify the contributions to fatigue of in-flight sleep versus time awake at top of descent. The study design was limited to eastward outbound flights with two Captains and two First Officers. Caution must be exercised when extrapolating to different operations. © 2013 European Sleep Research Society.

Major contributions to science

Energy Technology Data Exchange (ETDEWEB)

Martin, Andre

1991-03-15

It may look difficult to describe the scientific contributions of Léon Van Hove, who started his career as a pure mathematician, and then a mathematical physicist, and ended it as a phenomenologist and an adseveral of Léon's students, in particular N. Hugenholtz. In this domain, his contributions were numerous and fundamental.

Effective quantum theories with short- and long-range forces

International Nuclear Information System (INIS)

Koenig, Sebastian

2013-01-01

At low energies, nonrelativistic quantum systems are essentially governed by their wave functions at large distances. For this reason, it is possible to describe a wide range of phenomena with short- or even finite-range interactions. In this thesis, we discuss several topics in connection with such an effective description and consider, in particular, modifications introduced by the presence of additional long-range potentials. In the first part we derive general results for the mass (binding energy) shift of bound states with angular momentum L ≥ 1 in a periodic cubic box in two and three spatial dimensions. Our results have applications to lattice simulations of hadronic molecules, halo nuclei, and Feshbach molecules. The sign of the mass shift can be related to the symmetry properties of the state under consideration. We verify our analytical results with explicit numerical calculations. Moreover, we discuss the case of twisted boundary conditions that arise when one considers moving bound states in finite boxes. The corresponding finite-volume shifts in the binding energies play an important role in the study of composite-particle scattering on the lattice, where they give rise to topological correction factors. While the above results are derived under the assumption of a pure finite-range interaction - and are still true up to exponentially small correction in the short-range case - in the second part we consider primarily systems of charged particles, where the Coulomb force determines the long-range part of the potential. In quantum systems with short-range interactions, causality imposes nontrivial constraints on low-energy scattering parameters. We investigate these causality constraints for systems where a long-range Coulomb potential is present in addition to a short-range interaction. The main result is an upper bound for the Coulomb-modified effective range parameter. We discuss the implications of this bound to the effective feld theory (EFT) for

Microbiome variation in corals with distinct depth distribution ranges across a shallow-mesophotic gradient (15-85 m)

Science.gov (United States)

Glasl, Bettina; Bongaerts, Pim; Elisabeth, Nathalie H.; Hoegh-Guldberg, Ove; Herndl, Gerhard J.; Frade, Pedro R.

2017-06-01

Mesophotic coral ecosystems (MCEs) are generally poorly studied, and our knowledge of lower MCEs (below 60 m depth) is largely limited to visual surveys. Here, we provide a first detailed assessment of the prokaryotic community associated with scleractinian corals over a depth gradient to the lower mesophotic realm (15-85 m). Specimens of three Caribbean coral species exhibiting differences in their depth distribution ranges ( Agaricia grahamae, Madracis pharensis and Stephanocoenia intersepta) were collected with a manned submersible on the island of Curaçao, and their prokaryotic communities assessed using 16S rRNA gene sequencing analysis. Corals with narrower depth distribution ranges (depth-specialists) were associated with a stable prokaryotic community, whereas corals with a broader niche range (depth-generalists) revealed a higher variability in their prokaryotic community. The observed depth effects match previously described patterns in Symbiodinium depth zonation. This highlights the contribution of structured microbial communities over depth to the coral's ability to colonize a broader depth range.

Cubic–quintic long-range interactions with double well potentials

International Nuclear Information System (INIS)

Tsilifis, Panagiotis A; Kevrekidis, Panayotis G; Rothos, Vassilis M

2014-01-01

In the present work, we examine the combined effects of cubic and quintic terms of the long-range type in the dynamics of a double well potential. Employing a two-mode approximation, we systematically develop two cubic–quintic ordinary differential equations and assess the contributions of the long-range interactions in each of the relevant prefactors, gauging how to simplify the ensuing dynamical system. Finally, we obtain a reduced canonical description for the conjugate variables of relative population imbalance and relative phase between the two wells and proceed to a dynamical systems analysis of the resulting pair of ordinary differential equations. While in the case of cubic and quintic interactions of the same kind (e.g. both attractive or both repulsive), only a symmetry-breaking bifurcation can be identified, a remarkable effect that emerges e.g. in the setting of repulsive cubic but attractive quintic interactions is a ‘symmetry-restoring’ bifurcation. Namely, in addition to the supercritical pitchfork that leads to a spontaneous symmetry breaking of the antisymmetric state, there is a subcritical pitchfork that eventually reunites the asymmetric daughter branch with the antisymmetric parent one. The relevant bifurcations, the stability of the branches and their dynamical implications are examined both in the reduced (ODE) and in the full (PDE) setting. The model is argued to be of physical relevance, especially so in the context of optical thermal media. (paper)

Long-range GABAergic connections distributed throughout the neocortex and their possible function

Directory of Open Access Journals (Sweden)

Nobuaki eTamamaki

2010-12-01

Full Text Available Features and functions of long range GABAergic projection neurons in the developing cerebral cortex have been reported previously, although until now their significance in the adult cerebral cortex has remained uncertain. The septo-hippocampal circuit is one exception – in this system, long range mature GABAergic projection neurons have been well analyzed and their contribution to the generation of theta-oscillatory behavior in the hippocampus has been documented. To have a clue to the function of the GABAergic projection neurons in the neocortex, we view the long range GABAergic projections those participating in the cortico-cortical, cortico-fugal, and afferent projections in the cerebral cortex. Then, we consider the possibility that the GABAergic projection neurons are involved in the generation, modification, and/or synchronization of oscillations in mature neocortical neuron activity. When markers that identify the GABAergic projection neurons are examined in anatomical and developmental studies, it is clear that neuronal NO synthetase (nNOS-immunoreactivity can readily identify GABAergic projection fibers (i.e. those longer than 1.5 mm. To elucidate the role of the GABAergic projection neurons in the neocortex, it will be necessary to clarify the network constructed by nNOS-positive GABAergic projection neurons and their postsynaptic targets. Thus, our long-range goals will be to label and manipulate (including deleting the GABAergic projection neurons using genetic tools driven by a nNOS promoter. We recognize that this may be a complex endeavor, as most excitatory neurons in the murine neocortex express nNOS transiently. Nevertheless, additional studies characterizing long range GABAergic projection neurons will have great value to the overall understanding of mature cortical function.

Comparing ecohydrological processes in alien vs. native ranges: perspectives from the endangered shrub Myricaria germanica

Science.gov (United States)

Michielon, Bruno; Campagnaro, Thomas; Porté, Annabel; Hoyle, Jo; Picco, Lorenzo; Sitzia, Tommaso

2017-04-01

Comparing the ecology of woody species in their alien and native ranges may provide interesting insights for theoretical ecology, invasion biology, restoration ecology and forestry. The literature which describes the biological evolution of successful plant invaders is rich and increasing. However, no general theories have been developed about the geomorphic settings which may limit or favour the alien woody species expansion along rivers. The aim of this contribution is to explore the research opportunities in the comparison of ecohydrological processes occurring in the alien vs. the native ranges of invasive tree and shrub species along the riverine corridor. We use the endangered shrub Myricaria germanica as an example. Myricaria germanica is an Euro-Asiatic pioneer species that, in the native range, develops along natural rivers, wide and dynamic. These conditions are increasingly limited by anthropogenic constraints in most European rivers. This species has been recently introduced in New Zealand, where it is spreading in some natural rivers of the Canterbury region (South Island). We present the current knowledge about the natural and anthropogenic factors influencing this species in its native range. We compare this information with the current knowledge about the same factors influencing M. germanica invasiveness and invasibility of riparian habitats in New Zealand. We stress the need to identify potential factors which could drive life-traits and growing strategies divergence which may hinder the application to the alien ranges of existing ecohydrological knowledge from native ranges. Moreover, the pattern of expansion of the alien range of species endangered in their native ranges opens new windows for research.

Major contributions to science

International Nuclear Information System (INIS)

Martin, Andre

1991-01-01

It may look difficult to describe the scientific contributions of Léon Van Hove, who started his career as a pure mathematician, and then a mathematical physicist, and ended it as a phenomenologist and an adseveral of Léon's students, in particular N. Hugenholtz. In this domain, his contributions were numerous and fundamental

Metamemory and memory for a wide range of font sizes: What is the contribution of perceptual fluency?

Science.gov (United States)

Undorf, Monika; Zimdahl, Malte F

2018-04-26

Words printed in a larger 48-point font are judged to be more memorable than words printed in a smaller 18-point font, although font size does not affect actual memory. To clarify the basis of this font size effect on metamemory and memory, 4 experiments investigated how presenting words in 48 (Experiment 1) or 4 (Experiments 2 to 4) font sizes between 6 point and 500 point affected judgments of learning (JOLs) and recall performance. Response times in lexical decision tasks were used to measure perceptual fluency. In all experiments, perceptual fluency was lower for words presented in very small and very large font sizes than for words presented in intermediate font sizes. In contrast, JOLs increased monotonically with font size, even beyond the point where a large font impaired perceptual fluency. Assessments of people's metacognitive beliefs about font size revealed that the monotonic increase in JOLs was not due to beliefs masking perceptual fluency effects (Experiment 3). Also, JOLs still increased across the whole range of font sizes when perceptual fluency was made salient at study (Experiment 4). In all experiments but Experiment 4, recall performance increased with increasing font size, although to a lesser extent than JOLs. Overall, the current study supports the idea that metacognitive beliefs underlie font size effects in metamemory. As important, it reveals that people's font size beliefs have some accuracy. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Medium Range Forecasts Representation (and Long Range Forecasts?)

Science.gov (United States)

Vincendon, J.-C.

2009-09-01

The progress of the numerical forecasts urges us to interest us in more and more distant ranges. We thus supply more and more forecasts with term of some days. Nevertheless, precautions of use are necessary to give the most reliable and the most relevant possible information. Available in a TV bulletin or on quite other support (Internet, mobile phone), the interpretation and the representation of a medium range forecast (5 - 15 days) must be different from those of a short range forecast. Indeed, the "foresee-ability” of a meteorological phenomenon decreases gradually in the course of the ranges, it decreases all the more quickly that the phenomenon is of small scale. So, at the end of some days, the probability character of a forecast becomes very widely dominating. That is why in Meteo-France the forecasts of D+4 to D+7 are accompanied with a confidence index since around ten years. It is a figure between 1 and 5: the more we approach 5, the more the confidence in the supplied forecast is good. In the practice, an indication is supplied for period D+4 / D+5, the other one for period D+6 / D+7, every day being able to benefit from a different forecast, that is be represented in a independent way. We thus supply a global tendency over 24 hours with less and less precise symbols as the range goes away. Concrete examples will be presented. From now on two years, we also publish forecasts to D+8 / J+9, accompanied with a sign of confidence (" good reliability " or " to confirm "). These two days are grouped together on a single map because for us, the described tendency to this term is relevant on a duration about 48 hours with a spatial scale slightly superior to the synoptic scale. So, we avoid producing more than two zones of types of weather over France and we content with giving an evolution for the temperatures (still, in increase or in decline). Newspapers began to publish this information, it should soon be the case of televisions. It is particularly

Total nuclear photoabsorption cross section in the range 0.2 - 1.0 GeV for nuclei throughout the periodic table

International Nuclear Information System (INIS)

Terranova, M.L.; Tavares, O.A.P.

1993-01-01

An analysis of the total photoabsorption cross section for nuclei ranging from 4 He up to 238 U has been performed in the energy range 0.2-1.0 GeV. Mean total photoabsorption cross sections have been obtained by summing up the contributions from partial photo reactions, and found to follow an A l -dependence in the 0.2-1.0 GeV range. A review of the available total photoabsorption cross section data is also presented. Comparisons have been made with cross section values calculated by considering both the quasi-deuteron and π-meson photoproduction mechanism of primary nuclear photo interaction. (author)

EV range sensitivity analysis

Energy Technology Data Exchange (ETDEWEB)

Ostafew, C. [Azure Dynamics Corp., Toronto, ON (Canada)

2010-07-01

This presentation included a sensitivity analysis of electric vehicle components on overall efficiency. The presentation provided an overview of drive cycles and discussed the major contributors to range in terms of rolling resistance; aerodynamic drag; motor efficiency; and vehicle mass. Drive cycles that were presented included: New York City Cycle (NYCC); urban dynamometer drive cycle; and US06. A summary of the findings were presented for each of the major contributors. Rolling resistance was found to have a balanced effect on each drive cycle and proportional to range. In terms of aerodynamic drive, there was a large effect on US06 range. A large effect was also found on NYCC range in terms of motor efficiency and vehicle mass. figs.

Contributions: SAGE

Indian Academy of Sciences (India)

First page Back Continue Last page Overview Graphics. Contributions: SAGE. Space Alternating Generalized Expectation (SAGE) Maximization algorithm provides an iterative approach to parameter estimation when direct maximization of the likelihood function may be infeasible. Complexity is less in those applications ...

Various Contributions

Indian Academy of Sciences (India)

First page Back Continue Last page Overview Graphics. Various Contributions. Developed an Off –Diagonal MIMO Canceller to mitigate Upstream Crosstalk in VDSL. Developed a low complexity, Expectation Maximization based iterative Crosstalk cancellation. Developed an optimal way of computational complexity ...

Some examples illustrating the role of the degrees of freedom of quarks and mesons in the nucleus

International Nuclear Information System (INIS)

Chanfray, G.

1987-01-01

We investigate in this work some nuclear physics problems involving non-nucleonic degrees of freedom such as quarks, gluons or pions. This first section is devoted to the color dielectric model where the nuclear binding energy is directly related to the partial deconfinement of quarks and gluons in nuclei. In the second section, we show that a collection mechanism depopulates the delta response in favor of the so-called pionic branch. In the third section, we present a semi-classical calculation of the nuclear quasielastic responses going beyond Thomas-Fermi theory. In particular, this approach is applied to the problem of spin-isospin response-functions [fr

Unsynchronized scanning with a low-cost laser range finder for real-time range imaging

Science.gov (United States)

Hatipoglu, Isa; Nakhmani, Arie

2017-06-01

Range imaging plays an essential role in many fields: 3D modeling, robotics, heritage, agriculture, forestry, reverse engineering. One of the most popular range-measuring technologies is laser scanner due to its several advantages: long range, high precision, real-time measurement capabilities, and no dependence on lighting conditions. However, laser scanners are very costly. Their high cost prevents widespread use in applications. Due to the latest developments in technology, now, low-cost, reliable, faster, and light-weight 1D laser range finders (LRFs) are available. A low-cost 1D LRF with a scanning mechanism, providing the ability of laser beam steering for additional dimensions, enables to capture a depth map. In this work, we present an unsynchronized scanning with a low-cost LRF to decrease scanning period and reduce vibrations caused by stop-scan in synchronized scanning. Moreover, we developed an algorithm for alignment of unsynchronized raw data and proposed range image post-processing framework. The proposed technique enables to have a range imaging system for a fraction of the price of its counterparts. The results prove that the proposed method can fulfill the need for a low-cost laser scanning for range imaging for static environments because the most significant limitation of the method is the scanning period which is about 2 minutes for 55,000 range points (resolution of 250x220 image). In contrast, scanning the same image takes around 4 minutes in synchronized scanning. Once faster, longer range, and narrow beam LRFs are available, the methods proposed in this work can produce better results.

Short-range/Long-range Integrated Target (SLIT) for Video Guidance Sensor Rendezvous and Docking

Science.gov (United States)

Roe, Fred D. (Inventor); Bryan, Thomas C. (Inventor)

2009-01-01

A laser target reflector assembly for mounting upon spacecraft having a long-range reflector array formed from a plurality of unfiltered light reflectors embedded in an array pattern upon a hemispherical reflector disposed upon a mounting plate. The reflector assembly also includes a short-range reflector array positioned upon the mounting body proximate to the long-range reflector array. The short-range reflector array includes three filtered light reflectors positioned upon extensions from the mounting body. The three filtered light reflectors retro-reflect substantially all incident light rays that are transmissive by their monochromatic filters and received by the three filtered light reflectors. In one embodiment the short-range reflector array is embedded within the hemispherical reflector,

Human-Induced Effects on RSS Ranging Measurements for Cooperative Positioning

DEFF Research Database (Denmark)

Della Rosa, Francescantonio; Pelosi, Mauro; Nurmi, Jari

2012-01-01

of human-induced perturbations for enhancing the final positioning accuracy through cooperative schemes has been assessed. It has been proved that the effect of cooperation is very limited if human factors are not taken into account when performing experimental activities.......We present experimental evaluations of human-induced perturbations on received-signal-strength-(RSS-) based ranging measurements for cooperative mobile positioning. To the best of our knowledge, this work is the first attempt to gain insight and understand the impact of both body loss and hand grip...... on the RSS for enhancing proximity measurements among neighbouring devices in cooperative scenarios. Our main contribution is represented by experimental investigations. Analysis of the errors introduced in the distance estimation using path-loss-based methods has been carried out. Moreover, the exploitation...

Free Dietary Choice and Free-Range Rearing Improve the Product Quality, Gait Score, and Microbial Richness of Chickens

Directory of Open Access Journals (Sweden)

Siyu Chen

2018-06-01

Full Text Available Poultry welfare has been extensively studied; however, there is a lack of rigorous scientific knowledge relating to the different aspects of welfare factors and how this may contribute to the production quantity and product quality as well as the welfare of chickens. Therefore, we conducted an integrated study to compare welfare factors in chickens by providing free dietary choice under cage rearing, and further comparing cage rearing with free-range rearing. One hundred chickens each were allocated to a cage rearing group with conventional feeding (CC, a cage rearing group with free dietary choice of mealworms (FDM, a cage rearing group with free dietary choice of mealworms and fresh grass (FDMG, and a free-range rearing system group with free dietary choice of mealworms and fresh grass (FRMG. Results showed that under cage rearing, free dietary choice contributed to better meat quality and gait score, higher values of blood platelets, and a richer gut microbial composition, but poorer egg production than CC chickens. As compared to FDMG, FRMG chickens showed better meat quality, gait score, and feather conditions, as well as a richer gut microbial composition; however, they had poorer egg production and a poorer foot pad and foot feather condition. We conclude that free dietary choice and free-range rearing systems improve the product quality, gait score, and microbial richness of chickens.

The energetic contributions of aquatic primary producers to terrestrial food webs in a mid-size river system.

Science.gov (United States)

Kautza, Adam; Mazeika, S; Sullivan, P

2016-03-01

Rivers are increasingly recognized as providing nutritional subsidies (i.e., energy and nutrients) to adjacent terrestrial food webs via depredation of aquatic organisms (e.g., emergent aquatic insects, crayfish, fish) by terrestrial consumers. However, because these prey organisms assimilate energy from both aquatic (e.g., benthic algae, phytoplankton, aquatic macrophytes) and terrestrial (e.g., riparian leaf detritus) primary producers, river subsidies to terrestrial consumers represent a combination of aquatically and terrestrially derived energy. To date, the explicit contribution of energy derived from aquatic primary producers to terrestrial consumers has not been fully explored yet might be expected to be quantitatively important to terrestrial food webs. At 12 reaches along a 185-km segment of the sixth-order Scioto River system (Ohio, USA), we quantified the relative contribution of energy derived from aquatic primary producers to a suite of terrestrial riparian consumers that integrate the adjacent landscape across multiple spatial scales through their foraging activities (tetragnathid spiders, rove beetles, adult coenagrionid damselflies, riparian swallows, and raccoons). We used naturally abundant stable isotopes (13C and 15N) of periphyton, phytoplankton, macrophytes, and terrestrial vegetation to evaluate the energetic contribution of aquatic primary producers to terrestrial food webs. Shoreline tetragnathid spiders were most reliant on aquatic primary producers (50%), followed by wider-ranging raccoons (48%), damselflies (44%), and riparian swallows (41%). Of the primary producers, phytoplankton (19%) provisioned the greatest nutritional contribution to terrestrial consumers (considered collectively), followed by periphyton (14%) and macrophytes (11%). Our findings provide empirical evidence that aquatic primary producers of large streams and rivers can be a critical nutritional resource for terrestrial food webs. We also show that aquatically

Estimation of the recharge area contributing water to a pumped well in a glacial-drift, river-valley aquifer

Science.gov (United States)

Morrissey, Daniel J.

1989-01-01

The highly permeable, unconfined, glacial-drift aquifers that occupy most New England river valleys constitute the principal source of drinking water for many of the communities that obtain part or all of their public water supply from ground water. Recent events have shown that these aquifers are highly susceptible to contamination that results from a number of sources, such as seepage from wastewater lagoons, leaking petroleum-product storage tanks, and road salting. To protect the quality of water pumped from supply wells in these aquifers, it is necessary to ensure that potentially harmful contaminants do not enter the ground in the area that contributes water to the well. A high degree of protection can be achieved through the application of appropriate land-use controls within the contributing area. However, the contributing areas for most supply wells are not known. This report describes the factors that affect the size and shape of contributing areas to public supply wells and evaluates several methods that may be used to delineate contributing areas of wells in glacial-drift, river-valley aquifers. Analytical, two-dimensional numerical, and three-dimensional numerical models were used to delineate contributing areas. These methods of analysis were compared by applying them to a hypothetical aquifer having the dimensions and geometry of a typical glacial-drift, river-valley aquifer. In the model analyses, factors that control the size and shape of a contributing area were varied over ranges of values common to glacial-drift aquifers in New England. The controlling factors include the rate of well discharge, rate of recharge to the aquifer from precipitation and from adjacent till and bedrock uplands, distance of a pumping well from a stream or other potential source of induced recharge, degree of hydraulic connection of the aquifer with a stream, horizontal hydraulic conductivity of the aquifer, ratio of horizontal to vertical hydraulic conductivity, and

Predicting Long-Range Traversability from Short-Range Stereo-Derived Geometry

Science.gov (United States)

Turmon, Michael; Tang, Benyang; Howard, Andrew; Brjaracharya, Max

2010-01-01

Based only on its appearance in imagery, this program uses close-range 3D terrain analysis to produce training data sufficient to estimate the traversability of terrain beyond 3D sensing range. This approach is called learning from stereo (LFS). In effect, the software transfers knowledge from middle distances, where 3D geometry provides training cues, into the far field where only appearance is available. This is a viable approach because the same obstacle classes, and sometimes the same obstacles, are typically present in the mid-field and the farfield. Learning thus extends the effective look-ahead distance of the sensors.

Original contributions

African Journals Online (AJOL)

hefere

Original contributions ... Results suggest that there is a significant positive ... psychological abuse, including economic abuse, intimidation, harassment, stalking, damage ... or maintaining the structure and function of the African home (Alio et al., 2011; Jewkes,. Levin ... Revictimisation occurs due to emotional violence and.

Contributions of Nonhuman Primates to Research on Aging.

Science.gov (United States)

Didier, E S; MacLean, A G; Mohan, M; Didier, P J; Lackner, A A; Kuroda, M J

2016-03-01

Aging is the biological process of declining physiologic function associated with increasing mortality rate during advancing age. Humans and higher nonhuman primates exhibit unusually longer average life spans as compared with mammals of similar body mass. Furthermore, the population of humans worldwide is growing older as a result of improvements in public health, social services, and health care systems. Comparative studies among a wide range of organisms that include nonhuman primates contribute greatly to our understanding about the basic mechanisms of aging. Based on their genetic and physiologic relatedness to humans, nonhuman primates are especially important for better understanding processes of aging unique to primates, as well as for testing intervention strategies to improve healthy aging and to treat diseases and disabilities in older people. Rhesus and cynomolgus macaques are the predominant monkeys used in studies on aging, but research with lower nonhuman primate species is increasing. One of the priority topics of research about aging in nonhuman primates involves neurologic changes associated with cognitive decline and neurodegenerative diseases. Additional areas of research include osteoporosis, reproductive decline, caloric restriction, and their mimetics, as well as immune senescence and chronic inflammation that affect vaccine efficacy and resistance to infections and cancer. The purpose of this review is to highlight the findings from nonhuman primate research that contribute to our understanding about aging and health span in humans. © The Author(s) 2016.

The Contributions of Phonological and Morphological Awareness to Literacy Skills in the Adult Basic Education Population

Science.gov (United States)

Fracasso, Lucille E.; Bangs, Kathryn; Binder, Katherine S.

2016-01-01

The Adult Basic Education (ABE) population consists of a wide range of abilities with needs that may be unique to this set of learners. The purpose of this study was to better understand the relative contributions of phonological decoding and morphological awareness to spelling, vocabulary, and comprehension across a sample of ABE students. In…

Up- and Down-Quark Contributions to the Nucleon Form Factors

Directory of Open Access Journals (Sweden)

Qattan I. A.

2014-03-01

Full Text Available Recent measurements of the neutron s electric to magnetic form factors ratio, Rn = µnGnE/GnM, up to 3.4 (GeV/c2 combined with existing Rp = µpGpE/GpM measurements in the same Q2 range allowed, for the first time, a separation of the up- and downquark contributions to the form factors at high Q2, as presented by Cates, et al.. Our analysis expands on the original work by including additional form factor data, applying two-photon exchange (TPE corrections, and accounting for the uncertainties associated with all of the form factor measurements.

Viva la Familia Study: genetic and environmental contributions to childhood obesity and its comorbidities in the Hispanic population.

Science.gov (United States)

Butte, Nancy F; Cai, Guowen; Cole, Shelley A; Comuzzie, Anthony G

2006-09-01

Genetic and environmental contributions to childhood obesity are poorly delineated. The Viva la Familia Study was designed to genetically map childhood obesity and its comorbidities in the Hispanic population. The objectives of this report were to describe the study design and to summarize genetic and environmental contributions to the phenotypic variation in obesity and risk factors for metabolic diseases in Hispanic children. The Viva la Familia cohort consisted of 1030 children from 319 families selected based on an overweight proband between the ages of 4 and 19 y. In-depth phenotyping to characterize the overweight children and their siblings included anthropometric and body-composition traits by dual-energy X-ray absorptiometry and assessments of diet by 24-h recalls, physical activity by accelerometry, and risk factors for metabolic diseases by standard biochemical methods. Univariate quantitative genetic analysis was used to partition phenotypic variance into additive genetic and environmental components by using the computer program SOLAR. Sex, age, and environmental covariates explained 1-91% of the phenotypic variance. Heritabilities of anthropometric indexes ranged from 0.24 to 0.75. Heritability coefficients for the body-composition traits ranged from 0.18 to 0.35. Diet and physical activity presented heritabilities of 0.32 to 0.69. Risk factors for metabolic diseases were heritable with coefficients ranging from 0.25 to 0.73. Significant genetic correlations between obesity traits and risk factors for metabolic diseases substantiated pleiotropy between traits. The Viva la Familia Study provides evidence of a strong genetic contribution to the high prevalence of obesity and its comorbidities in Hispanic children.

Storm Identification, Tracking and Forecasting Using High-Resolution Images of Short-Range X-Band Radar

Directory of Open Access Journals (Sweden)

Sajid Shah

2015-05-01

Full Text Available Rain nowcasting is an essential part of weather monitoring. It plays a vital role in human life, ranging from advanced warning systems to scheduling open air events and tourism. A nowcasting system can be divided into three fundamental steps, i.e., storm identification, tracking and nowcasting. The main contribution of this work is to propose procedures for each step of the rain nowcasting tool and to objectively evaluate the performances of every step, focusing on two-dimension data collected from short-range X-band radars installed in different parts of Italy. This work presents the solution of previously unsolved problems in storm identification: first, the selection of suitable thresholds for storm identification; second, the isolation of false merger (loosely-connected storms; and third, the identification of a high reflectivity sub-storm within a large storm. The storm tracking step of the existing tools, such as TITANand SCIT, use only up to two storm attributes, i.e., center of mass and area. It is possible to use more attributes for tracking. Furthermore, the contribution of each attribute in storm tracking is yet to be investigated. This paper presents a novel procedure called SALdEdA (structure, amplitude, location, eccentricity difference and areal difference for storm tracking. This work also presents the contribution of each component of SALdEdA in storm tracking. The second order exponential smoothing strategy is used for storm nowcasting, where the growth and decay of each variable of interest is considered to be linear. We evaluated the major steps of our method. The adopted techniques for automatic threshold calculation are assessed with a 97% goodness. False merger and sub-storms within a cluster of storms are successfully handled. Furthermore, the storm tracking procedure produced good results with an accuracy of 99.34% for convective events and 100% for stratiform events.

Direct measurement of two-electron contributions to the ground state energy of heliumlike high-Z ions

International Nuclear Information System (INIS)

Stoehlker, T.; Elliott, S.R.; Marrs, R.E.

1995-09-01

We report on a novel technique which exploits Radiative Recombination transitions for a direct experimental determination of the two-electron contributions to the ground state energy in heliumlike high-Z ions. Results are presented of a first experiment which was conducted at an electron beam ion trap for various elements ranging from Z=32 to 83. The comparison with theoretical predictions demonstrates that the achieved precision already provides a sensitive test of second order manybody contributions and approaches the size of the two-electron (screened) Lamb shift. The ptoential of the new technique will be outlined and the capability of the ESR storage ring for future investigations will be emphasized. (orig.)

National contributions to observed global warming

International Nuclear Information System (INIS)

Matthews, H Damon; Graham, Tanya L; Keverian, Serge; Lamontagne, Cassandra; Seto, Donny; Smith, Trevor J

2014-01-01

There is considerable interest in identifying national contributions to global warming as a way of allocating historical responsibility for observed climate change. This task is made difficult by uncertainty associated with national estimates of historical emissions, as well as by difficulty in estimating the climate response to emissions of gases with widely varying atmospheric lifetimes. Here, we present a new estimate of national contributions to observed climate warming, including CO 2 emissions from fossil fuels and land-use change, as well as methane, nitrous oxide and sulfate aerosol emissions While some countries’ warming contributions are reasonably well defined by fossil fuel CO 2 emissions, many countries have dominant contributions from land-use CO 2 and non-CO 2 greenhouse gas emissions, emphasizing the importance of both deforestation and agriculture as components of a country’s contribution to climate warming. Furthermore, because of their short atmospheric lifetime, recent sulfate aerosol emissions have a large impact on a country’s current climate contribution We show also that there are vast disparities in both total and per-capita climate contributions among countries, and that across most developed countries, per-capita contributions are not currently consistent with attempts to restrict global temperature change to less than 2 °C above pre-industrial temperatures. (paper)

Effects of air-sea interaction on extended-range prediction of geopotential height at 500 hPa over the northern extratropical region

Science.gov (United States)

Wang, Xujia; Zheng, Zhihai; Feng, Guolin

2018-04-01

The contribution of air-sea interaction on the extended-range prediction of geopotential height at 500 hPa in the northern extratropical region has been analyzed with a coupled model form Beijing Climate Center and its atmospheric components. Under the assumption of the perfect model, the extended-range prediction skill was evaluated by anomaly correlation coefficient (ACC), root mean square error (RMSE), and signal-to-noise ratio (SNR). The coupled model has a better prediction skill than its atmospheric model, especially, the air-sea interaction in July made a greater contribution for the improvement of prediction skill than other months. The prediction skill of the extratropical region in the coupled model reaches 16-18 days in all months, while the atmospheric model reaches 10-11 days in January, April, and July and only 7-8 days in October, indicating that the air-sea interaction can extend the prediction skill of the atmospheric model by about 1 week. The errors of both the coupled model and the atmospheric model reach saturation in about 20 days, suggesting that the predictable range is less than 3 weeks.

The contributing role of tourism in the HIV/AIDS epidemic in the Caribbean.

Science.gov (United States)

Orisatoki, R O; Oguntibeju, O O; Truter, E J

2009-01-01

The first confirmed case of HIV/AIDS in the Caribbean was reported in 1982, however a recent report by UNAIDS shows that the epidemic has risen to over 250,000 persons living with the virus with the highest prevalence rates shown to be in the Dominican Republic and Haiti. Various factors ranging from commercial sex trading to unsafe injection employed for drug abuse have been identified to play a contributing role in this increase. Also, the role and impact of tourism on the spread of HIV infection has been reported. Due to concerns shown by countries and territories who are dependent on tourism and that they rank amongst the most highly affected by HIV/AIDS in the region, this paper endeavours to examine the impact of HIV/AIDS and the contributing role of tourism to HIV/AIDS epidemic in the Caribbean.

7 CFR 966.45 - Contributions.

Science.gov (United States)

2010-01-01

... contributions but these shall only be used for production research, market research and development and marketing and promotion including paid advertising pursuant to § 966.48. Furthermore, such contributions..., 1986] Research and Development ...

Common-but-differentiated-Responsibilities for adaptation financing. An assessment of the contributions of countries

Energy Technology Data Exchange (ETDEWEB)

Dellink, R. [Wageningen University, Wageningen (Netherlands); Den Elzen, M. [Netherlands Environmental Assessment Agency NMP, Bilthoven (Netherlands); Aikinga, H.; Bergsm, E.; Berkhout, F.; Dekker, T.; Gupta, J. [Institute for Environmental Studies IVM, VU University, Amsterdam (Netherlands)

2009-03-15

Climate change may cause most harm to countries that have historically contributed the least to greenhouse gas emissions and land-use change. This paper identifies deontology, solidarity and consequentialism as the principles that can serve as a basis for a fair international burden sharing scheme of climate change adaptation costs. We translate these principles into criteria that can be applied in assigning a share of the financial burden to individual countries, namely historical responsibility, equality and capacity to pay. Specific political and scientific choices are discussed, highlighting implications for international burden-sharing schemes. A hybrid approach, combining historical responsibility and capacity to pay seems a promising starting point for international negotiations on the design of burden-sharing schemes. From the numerical assessment, it is clear that UNFCCC Annex I countries carry the greatest burden under most scenarios, but contributions differ substantially subject to the choice of an indicator for capacity to pay. The contributions are less sensitive to choices related to responsibility calculations, apart from those associated with land-use related emissions. Assuming the costs of climate adaptation are USD100 billion per year, the total financial contribution by the Annex I countries would be in the range of USD 55-68 billion per year.

Foraging optimally for home ranges

Science.gov (United States)

Mitchell, Michael S.; Powell, Roger A.

2012-01-01

Economic models predict behavior of animals based on the presumption that natural selection has shaped behaviors important to an animal's fitness to maximize benefits over costs. Economic analyses have shown that territories of animals are structured by trade-offs between benefits gained from resources and costs of defending them. Intuitively, home ranges should be similarly structured, but trade-offs are difficult to assess because there are no costs of defense, thus economic models of home-range behavior are rare. We present economic models that predict how home ranges can be efficient with respect to spatially distributed resources, discounted for travel costs, under 2 strategies of optimization, resource maximization and area minimization. We show how constraints such as competitors can influence structure of homes ranges through resource depression, ultimately structuring density of animals within a population and their distribution on a landscape. We present simulations based on these models to show how they can be generally predictive of home-range behavior and the mechanisms that structure the spatial distribution of animals. We also show how contiguous home ranges estimated statistically from location data can be misleading for animals that optimize home ranges on landscapes with patchily distributed resources. We conclude with a summary of how we applied our models to nonterritorial black bears (Ursus americanus) living in the mountains of North Carolina, where we found their home ranges were best predicted by an area-minimization strategy constrained by intraspecific competition within a social hierarchy. Economic models can provide strong inference about home-range behavior and the resources that structure home ranges by offering falsifiable, a priori hypotheses that can be tested with field observations.

Harnessing Big-Data for Estimating the Energy Consumption and Driving Range of Electric Vehicles

DEFF Research Database (Denmark)

Fetene, Gebeyehu Manie; Prato, Carlo Giacomo; Kaplan, Sigal

-effects econometrics model used in this paper predicts that the energy saving speed of driving is between 45 and 56 km/h. In addition to the contribution to the literature about energy efficiency of electric vehicles, the findings from this study enlightens consumers to choose appropriate cars that suit their travel......This study analyses the driving range and investigates the factors affecting the energy consumption rate of fully-battery electric vehicles under real-world driving patterns accounting for weather condition, drivers’ characteristics, and road characteristics. Four data sources are used: (i) up...

Pion mass dependence of the HVP contribution to muon g - 2

Science.gov (United States)

Golterman, Maarten; Maltman, Kim; Peris, Santiago

2018-03-01

One of the systematic errors in some of the current lattice computations of the HVP contribution to the muon anomalous magnetic moment g - 2 is that associated with the extrapolation to the physical pion mass. We investigate this extrapolation assuming lattice pion masses in the range of 220 to 440 MeV with the help of two-loop chiral perturbation theory, and find that such an extrapolation is unlikely to lead to control of this systematic error at the 1% level. This remains true even if various proposed tricks to improve the chiral extrapolation are taken into account.

Quantification of the sources of long-range transport of PM2.5 pollution in the Ordos region, Inner Mongolia, China

International Nuclear Information System (INIS)

Khuzestani, Reza Bashiri; Schauer, James J.; Wei, Yongjie; Zhang, Lulu; Cai, Tianqi; Zhang, Yang; Zhang, Yuanxun

2017-01-01

The Ordos region of Inner Mongolia is rapidly developing and suffers from poor air quality and unhealthy levels of fine particulate matter. PM 2.5 concentrations in the Ordos region were found to exceed 75 μg/m 3 on average, annually, with peak pollution days in excess of 350 μg/m 3 , but local air pollution emissions from surrounding sources are not sufficient to drive pollution levels to these concentrations. The current study was designed to quantify sources of PM 2.5 and assess the local source contributions and effects of regional transport on local pollution. The results show that the Ordos region is primarily impacted by regional long-range transport of pollutants from anthropogenic sources located outside of the Inner Mongolia in Shanxi province areas but is also largely affected by regional dust transported from the deserts located in western Inner Mongolia. The analysis proved that approximately 77% of PM 2.5 mass is transported long-range from the sites exterior to the study area and contributes 59.32 μg/m 3 on average, annually, while the local sources contribute 17.41 μg/m 3 (23%) on annual average to the PM 2.5 mass in the study area. High spatial correlation coefficients (R 2  > 0.6) were observed for most of the factors pointing to the transport of external emissions into the area. Spatial correlation analysis, bivariate polar plots and hybrid trajectory models for industrial and secondary inorganic factors provide evidence for the impact of long-range transport from Shanxi province areas. In addition, the deserts in western Inner Mongolia were found to be the source regions for dust. Finally, our analysis shows that the source of oil combustion and mobile factors are impacted by local sources in the Ordos region; however, some regional impacts from other regions were also observed for mobile source in the area. - Dominance of the regional long-range transport of PM 2.5 sources in the Ordos region. Around 77% of PM 2.5 mass is transported

Student Scientific Conference, 2010. Proceedings of reviewed contributions

International Nuclear Information System (INIS)

2010-01-01

The conference included the following sections: (i) Biology (154 contributions); (ii) Chemistry (39 contributions); (iii) Geography; (41 contributions); (iv) Geology (22 contributions); (v) Environment (45 contributions); (vi) Didactics (6 contributions). Contributions relevant of INIS interest has been inputted to INIS.

Student Scientific Conference, 2009. Proceedings of reviewed contributions

International Nuclear Information System (INIS)

2009-01-01

The conference included the following sections: (i) Biology (145 contributions); (ii) Chemistry (42 contributions); (iii) Geology (42 contributions); (iv) Environment (40 contributions); (v) Geography (28 contributions); (vi) Didactics (13 contributions). Contributions relevant of INIS interest has been inputted to INIS.

Electrodynamic properties of porous PZT-Pt films at terahertz frequency range

Energy Technology Data Exchange (ETDEWEB)

Komandin, Gennady A.; Porodinkov, Oleg E.; Spektor, Igor E.; Volkov, Alexander A. [Prokhorov General Physics Institute, Russian Academy of Sciences, Moscow (Russian Federation); Vorotilov, Konstantin A.; Seregin, Dmitry S.; Sigov, Alexander S. [Moscow Technological University (MIREA), Moscow (Russian Federation)

2017-01-15

Electrodynamics of Si-SiO{sub 2}-TiO{sub 2}-Pt-PZT heterostructures is studied in the frequency range from 5 to 5000 cm{sup -1} by monochromatic BWO (backward wave oscillator) and infrared Fourier-transform spectroscopy techniques to derive the dielectric characteristics of the sol-gel porous ferroelectric PbZr{sub 0.48}Ti{sub 0.52}O{sub 3} films. Broad frequency band dielectric response of PZT films with different density is constructed using the oscillator dispersion models. The main contribution to the film permittivity is found to form at frequencies below 100 cm{sup -1} depending strongly and non-linearly on the film medium density. (copyright 2016 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Researching in the community: the value and contribution of nurses to community based or primary health care research.

Science.gov (United States)

Barthow, Christine; Jones, Bernadette; Macdonald, Lindsay; Vernall, Sue; Gallagher, Peter; McKinlay, Eileen

2015-05-01

To describe the role, contribution and value of research nurses in New Zealand community-based or primary health care research. Research nurses are increasingly recognised as having a key role in undertaking successful research in hospitals and clinical trial units however only limited work has been undertaken to examine their role in community-based research. Undertaking health research in the community has unique challenges particularly in relation to research design and recruitment and retention of participants. We describe four community-based research projects involving research nurses, each with particular recruitment, retention and logistical problems. Vignettes are used to illustrate the role, contribution and value of research nurses in a diverse range of community research projects. The knowledge and skills used by research nurses in these projects included familiarity with communities, cultural competence, health care systems and practice philosophies and in particular with vulnerable populations. Their research actions and activities include competence with a broad range of research methodologies, organisational efficiency, family-centred approach, along with advocacy and flexibility. These are underpinned by nursing knowledge and clinical expertise contributing to an ability to work autonomously. These four projects demonstrate that research nurses in community-based research possess specific attributes which facilitate successful study development, implementation and outcome.

Range Scheduling Aid (RSA)

Science.gov (United States)

Logan, J. R.; Pulvermacher, M. K.

1991-01-01

Range Scheduling Aid (RSA) is presented in the form of the viewgraphs. The following subject areas are covered: satellite control network; current and new approaches to range scheduling; MITRE tasking; RSA features; RSA display; constraint based analytic capability; RSA architecture; and RSA benefits.

Living to the range limit: consumer isotopic variation increases with environmental stress

Directory of Open Access Journals (Sweden)

Carl J. Reddin

2016-06-01

Full Text Available Background: Theoretically, each species’ ecological niche is phylogenetically-determined and expressed spatially as the species’ range. However, environmental stress gradients may directly or indirectly decrease individual performance, such that the precise process delimiting a species range may not be revealed simply by studying abundance patterns. In the intertidal habitat the vertical ranges of marine species may be constrained by their abilities to tolerate thermal and desiccation stress, which may act directly or indirectly, the latter by limiting the availability of preferred trophic resources. Therefore, we expected individuals at greater shore heights to show greater variation in diet alongside lower indices of physiological condition. Methods: We sampled the grazing gastropod Echinolittorina peruviana from the desert coastline of northern Chile at three shore heights, across eighteen regionally-representative shores. Stable isotope values (δ13C and δ15N were extracted from E. peruviana and its putative food resources to estimate Bayesian ellipse area, carbon and nitrogen ranges and diet. Individual physiological condition was tracked by muscle % C and % N. Results: There was an increase in isotopic variation at high shore levels, where E. peruviana’s preferred resource, tide-deposited particulate organic matter (POM, appeared to decrease in dietary contribution, and was expected to be less abundant. Both muscle % C and % N of individuals decreased with height on the shore. Discussion: Individuals at higher stress levels appear to be less discriminating in diet, likely because of abiotic forcing, which decreases both consumer mobility and the availability of a preferred resource. Abiotic stress might be expected to increase trophic variation in other selective dietary generalist species. Where this coincides with a lower physiological condition may be a direct factor in setting their range limit.

Are fish outside their usual ranges early indicators of climate-driven range shifts?

Science.gov (United States)

Fogarty, Hannah E; Burrows, Michael T; Pecl, Gretta T; Robinson, Lucy M; Poloczanska, Elvira S

2017-05-01

Shifts in species ranges are a global phenomenon, well known to occur in response to a changing climate. New species arriving in an area may become pest species, modify ecosystem structure, or represent challenges or opportunities for fisheries and recreation. Early detection of range shifts and prompt implementation of any appropriate management strategies is therefore crucial. This study investigates whether 'first sightings' of marine species outside their normal ranges could provide an early warning of impending climate-driven range shifts. We examine the relationships between first sightings and marine regions defined by patterns of local climate velocities (calculated on a 50-year timescale), while also considering the distribution of observational effort (i.e. number of sampling days recorded with biological observations in global databases). The marine trajectory regions include climate 'source' regions (areas lacking connections to warmer areas), 'corridor' regions (areas where moving isotherms converge), and 'sink' regions (areas where isotherms locally disappear). Additionally, we investigate the latitudinal band in which first sightings were recorded, and species' thermal affiliations. We found that first sightings are more likely to occur in climate sink and 'divergent' regions (areas where many rapid and diverging climate trajectories pass through) indicating a role of temperature in driving changes in marine species distributions. The majority of our fish first sightings appear to be tropical and subtropical species moving towards high latitudes, as would be expected in climate warming. Our results indicate that first sightings are likely related to longer-term climatic processes, and therefore have potential use to indicate likely climate-driven range shifts. The development of an approach to detect impending range shifts at an early stage will allow resource managers and researchers to better manage opportunities resulting from range

Contribution inequality in the spatial public goods game: Should the rich contribute more?

Science.gov (United States)

Tu, Jing

2018-04-01

Scale-free property exists in resource distribution, and the rich pay more in public goods is commonplace in reality. What will happen if the rich are expected to contribute more in the spatial public goods game? This paper therefore proposes a new contribution paradigm, in which individual contribution is determined by his payoff in the last evolution step. Tunable parameter w is used to characterize the contribution rate of nodes whose payoff is larger than the average. The results of simulations reveal that the impact of w on cooperation is associated with the enhancement factor r. When r is low, the higher w is, the lower the cooperation rate is. With the increment of r, the value of w to optimize cooperation rate increases with r. The relationship of cooperation rate and wealth on the network has also been investigated. Interestingly, higher cooperation rate does not always lead to higher wealth. Finally, the impact of w on the wealth distribution on the network is explored. The higher w reduces the inequality in wealth distribution by the shrinking of lower-class, which is enhanced by a higher r.

Scalar contribution to the BFKL kernel

International Nuclear Information System (INIS)

Gerasimov, R. E.; Fadin, V. S.

2010-01-01

The contribution of scalar particles to the kernel of the Balitsky-Fadin-Kuraev-Lipatov (BFKL) equation is calculated. A great cancellation between the virtual and real parts of this contribution, analogous to the cancellation in the quark contribution in QCD, is observed. The reason of this cancellation is discovered. This reason has a common nature for particles with any spin. Understanding of this reason permits to obtain the total contribution without the complicated calculations, which are necessary for finding separate pieces.

An assessment of the meteoritic contribution to the Martian soil

International Nuclear Information System (INIS)

Flynn, G.J.; McKay, D.S.

1990-01-01

The addition of meteoritic material to the Mars soils should perturb their chemical compositions, as has been detected for soils on the Moon and sediments on Earth. Using the measured mass influx at Earth and estimates of the Mars/Earth flux ratio, the authors estimate the continuous, planet-wide meteoritic mass influx on Mars to be between 2,700 and 59,000 t/yr. If distributed uniformly into a soil with a mean planetary production rate of 1 m/b.y., consistent with radar estimates of the soil depth overlaying a bouldered terrain in the Tharsis region, their estimated mass influx would produce a meteoritic concentration in the Mars soil ranging from 2 to 29% by mass. Analysis of the Viking X ray fluorescence data indicates that the Mars soil composition is inconsistent with typical basaltic rock fragments but can be fit by a mixture of 60% basaltic rock fragments and 40% meteoritic material. The meteoritic influx they calculate is sufficient to provide most or all of the material required by the Clark and Baird model. Particles in the mass range from 10 -7 to 10 -3 g, about 60-1,200 μm in diameter, contribute 80% of the total mass flux of meteoritic material in the 10 -13 to 10 6 g mass range at Earth. On Earth atmospheric entry all but the smallest particles (generally ≤ 50 μm in diameter) in the 10 -7 to 10 -3 g mass range are heated sufficiently to melt or vaporize. Mars, because of its lower escape velocity and larger atmospheric scale height, is a much more favorable site for unmelted survival of micrometeorites on atmospheric deceleration. They calculate that a significant fraction of particles throughout the 60-1,200 μm diameter range will survive Mars atmospheric entry unmelted

Focus group interviews examining the contribution of intellectual disability clinical nurse specialists in Ireland.

Science.gov (United States)

Doody, Owen; Slevin, Eamonn; Taggart, Laurence

2017-10-01

To explore the contribution of clinical nurse specialists in intellectual disability nursing in Ireland. While clinical nurse specialists exist since the 1940s, they have only been a reality in Ireland since 2001. While the role of clinical nurse specialist has developed over the years, it still however is often seen as a complex multifaceted role that causes confusion, frustration and controversy. A exploratory qualitative approach using focus groups with Irish intellectual disability clinical nurse specialists (n = 31). Five focus group interviews were conducted to gather qualitative data to gain insight into the attitudes, perceptions and opinions of the participants. Data were audio-recorded, transcribed and analysed using Burnard's (Vital Notes for Nurses: Research for Evidence-Based Practice in Healthcare, 2011, Blackwell Publishing, Oxford) framework. Ethical approval was gained from the researcher's university and access granted by the national council for the professional development of nursing/midwifery in Ireland. The study highlights that intellectual disability clinical nurse specialists contribute to and support care delivery across a range of areas including client-focused and family-centred care, staff support, organisation support, community support and supporting other agencies. Overall, the study shows the importance of intellectual disability clinical nurse specialists and their contribution across a range of services, care environments and the support they offer to clients/families/staff/multidisciplinary team members and outside agencies. Ireland is in a unique position to develop knowledge regarding specialist care for people with intellectual disability that can be shared and adapted by other healthcare professionals in other countries that do not have specialised intellectual disability nurses. © 2016 John Wiley & Sons Ltd.

PROBABILISTIC MODEL OF LASER RANGE FINDER FOR THREE DIMENSIONAL GRID CELL IN CLOSE RANGE ENVIRONMENT

Directory of Open Access Journals (Sweden)

Hafiz b Iman

2016-04-01

Full Text Available The probabilistic model of a laser scanner presents an important aspect for simultaneous localization and map-building (SLAM. However, the characteristic of the beam of the laser range finder under extreme incident angles approaching 900 has not been thoroughly investigated. This research paper reports the characteristic of the density of the range value coming from a laser range finder under close range circumstances where the laser is imposed with a high incident angle. The laser was placed in a controlled environment consisting of walls at a close range and 1000 iteration of scans was collected. The assumption of normal density of the metrical data collapses when the beam traverses across sharp edges in this environment. The data collected also shows multimodal density at instances where the range has discontinuity. The standard deviation of the laser range finder is reported to average at 10.54 mm, with 0.96 of accuracy. This significance suggests that under extreme incident angles, a laser range finder reading behaves differently compared to normal distribution. The use of this information is crucial for SLAM activity in enclosed environments such as inside piping grid or other cluttered environments.KEYWORDS:   Hokuyo UTM-30LX; kernel density estimation; probabilistic model  

Universal dispersion model for characterization of optical thin films over wide spectral range: Application to magnesium fluoride

Science.gov (United States)

Franta, Daniel; Nečas, David; Giglia, Angelo; Franta, Pavel; Ohlídal, Ivan

2017-11-01

Optical characterization of magnesium fluoride thin films is performed in a wide spectral range from far infrared to extreme ultraviolet (0.01-45 eV) utilizing the universal dispersion model. Two film defects, i.e. random roughness of the upper boundaries and defect transition layer at lower boundary are taken into account. An extension of universal dispersion model consisting in expressing the excitonic contributions as linear combinations of Gaussian and truncated Lorentzian terms is introduced. The spectral dependencies of the optical constants are presented in a graphical form and by the complete set of dispersion parameters that allows generating tabulated optical constants with required range and step using a simple utility in the newAD2 software package.

Hematology and serum chemistry reference ranges of free-ranging moose (Alces alces) in Norway.

Science.gov (United States)

Rostal, Melinda K; Evans, Alina L; Solberg, Erling J; Arnemo, Jon M

2012-07-01

Baseline reference ranges of serum chemistry and hematology data can be important indicators for the status of both individuals or populations of wild animals that are affected by emerging pathogens, toxicants, or other causes of disease. Frequently, reference ranges for these values are not available for wildlife species or subspecies. We present hematologic and serum chemistry reference ranges for moose (Alces alces) adults, yearlings, and calves in Norway sampled from 1992-2000. Additionally, we demonstrated that both induction time and chase time were correlated with initial rectal temperature, although they were not significantly correlated with cortisol, aspartate aminotransferase, glucose, or creatine kinase. Overall, the reference ranges given here are similar to those given for American moose, with a few differences that can be attributed to environment, testing methodology, or subspecies or species status. This is the first report, to our knowledge, of reference ranges for moose in Norway.

Analyses of Alpha-Alpha Elastic Scattering Data in the Energy Range 140 - 280 MeV

Energy Technology Data Exchange (ETDEWEB)

Shehadeh, Zuhair F. [Taif University, Taif (Saudi Arabia)

2017-01-15

The differential and the reaction cross-sections for 4He-4He elastic scattering data have been nicely obtained at four energies ranging from 140 MeV to 280 MeV (lab system), namely, 140, 160, 198 and 280 MeV, by using a new optical potential with a short-range repulsive core. The treatment has been handled relativistically as υ/c > 0.25 for the two lower energies and υ/c > 0.31 for the two higher ones. In addition to explaining the elastic angular distributions, the adopted potentials accounted for the structure that may exist at angles close to 90◦ , especially for the 198 and the 280-MeV incident energies. No renormalization has been used, and all our potential parameters are new. The necessity of including a short-range repulsive potential term in our real nuclear potential part has been demonstrated. Our results contribute to solving a long-standing problem concerning the nature of the alpha-alpha potential. This is very beneficial in explaining unknown alpha-nucleus and nucleus-nucleus relativistic reactions by using the cluster formalism.

Engaging western landowners in climate change mitigation: a guide to carbon-oriented forest and range management and carbon market opportunities

Science.gov (United States)

David D. Diaz; Susan Charnley; Hannah Gosnell

2009-01-01

There are opportunities for forest owners and ranchers to participate in emerging carbon markets and contribute to climate change mitigation through carbon oriented forest and range management activities. These activities often promote sutainable forestry and ranching and broader conservation goals while having the potential to provide a new income stream for...

Crust-mantle contribution to Andean magmatism

International Nuclear Information System (INIS)

Ruiz, J; Hildreth, W; Chesley, J

2001-01-01

There has long been great interest in quantifying the contributions of the continental crust to continental arc magmas, such as those of the Andes using osmium isotopes (Alves et al., 1999; Borg et al., 2000; Brandon et al., 1996; McInnes et al., 1999). In general, Andean volcanic rocks of all compositions show relatively low Sr-isotope ratios and positive to mildly negative epsilon Nd values. Nonetheless, in the Southern Volcanic Zone of central Chile, basalt-andesite-dacite volcanoes along the Quaternary volcanic front were shown (by Hildreth and Moorbath, 1988) to have latitudinally systematic chemical variations, as well as a monotonic increase in 87Sr/Sr86 from ca. 0.7035 to 0.7055 and a decrease in epsilon Nd values from ca. +3 to -1. The isotopic variations correlate with basement elevation of the volcanic edifices and with Bouguer gravity anomalies, both of which are thought to reflect along-arc variations in thickness and average age of the underlying crust. Volcanoes with the most evolved isotopic signatures were fed through the thickest crust. Correlation of chemical and isotopic variations with crustal thickness was interpreted to be caused by Melting (of deep-crustal host rocks), Assimilation, Storage, and Homogenization (MASH) of mantle-derived magmas in long-lived lower-crustal reservoirs beneath each center prior to eruption. We have now determined Os-isotope ratios for a sample suite from these volcanoes (33-36 S lat.), representing a range of crustal thickness from ca. 60-35 km. The samples range in MgO from ca. 8-4% and in SiO2 from 51-57%. The most evolved eruptive products occur above the thickest crust and have 87Sr/86Sr ratios of 0.7054 and epsilon Nd values of -1.5. The 187Os/188Os ratios correlate with the other isotopic systems and with crustal thickness. Volcanoes on the thinnest crust have 187Os/188Os ratios of 0.18-0.21. Those on the thickest crust have 187Os/188Os ratios as high as 0.64. All the Os values are much too radiogenic to

Potential trophic cascades triggered by the barred owl range expansion

Science.gov (United States)

Holm, Samantha R.; Noon, Barry R.; Wiens, David; Ripple, William J.

2016-01-01

Recently, the barred owl (Strix varia) has expanded its range into the Pacific Northwest of the United States resulting in pronounced effects on the demography and behavior of the northern spotted owl (S. occidentalis caurina). The range expansion has brought together historically allopatric species, creating the potential for significant changes in the avian predator community with possible cascading effects on food-web dynamics. The adverse effects of the barred owl on the behavior and demography of the northern spotted owl are well-documented, but little is known about the immediate and long-term effects changes in the predator community may have on native species composition and ecosystem processes. Based on northern spotted owl and barred owl selection for diet and habitat resources, there is a potential for trophic cascades within the region's predator and prey communities, differing responses by their shared and unique prey species, and possible direct and indirect effects on ecosystem processes. We explored the possible ecological consequences of the barred owl range expansion to wildlife communities of the Pacific Northwest based on the theoretical underpinnings of predator–prey relationships, interspecific competition, intraguild predation, and potential cascading trophic interactions. Negative effects on fitness of northern spotted owls because of interspecific competition with barred owls are strong selection forces that may contribute to the regional extinction of the northern spotted owl. In addition, we posit that shared prey species and those uniquely consumed by barred owls, along with other competing native predators, may experience changes in behavior, abundance, and distribution as a result of increased rates of predation by rapidly expanding populations of barred owls.

Real-space, mean-field algorithm to numerically calculate long-range interactions

Science.gov (United States)

Cadilhe, A.; Costa, B. V.

2016-02-01

Long-range interactions are known to be of difficult treatment in statistical mechanics models. There are some approaches that introduce a cutoff in the interactions or make use of reaction field approaches. However, those treatments suffer the illness of being of limited use, in particular close to phase transitions. The use of open boundary conditions allows the sum of the long-range interactions over the entire system to be done, however, this approach demands a sum over all degrees of freedom in the system, which makes a numerical treatment prohibitive. Techniques like the Ewald summation or fast multipole expansion account for the exact interactions but are still limited to a few thousands of particles. In this paper we introduce a novel mean-field approach to treat long-range interactions. The method is based in the division of the system in cells. In the inner cell, that contains the particle in sight, the 'local' interactions are computed exactly, the 'far' contributions are then computed as the average over the particles inside a given cell with the particle in sight for each of the remaining cells. Using this approach, the large and small cells limits are exact. At a fixed cell size, the method also becomes exact in the limit of large lattices. We have applied the procedure to the two-dimensional anisotropic dipolar Heisenberg model. A detailed comparison between our method, the exact calculation and the cutoff radius approximation were done. Our results show that the cutoff-cell approach outperforms any cutoff radius approach as it maintains the long-range memory present in these interactions, contrary to the cutoff radius approximation. Besides that, we calculated the critical temperature and the critical behavior of the specific heat of the anisotropic Heisenberg model using our method. The results are in excellent agreement with extensive Monte Carlo simulations using Ewald summation.

New progress of ranging technology at Wuhan Satellite Laser Ranging Station

Science.gov (United States)

Xia, Zhiz-Hong; Ye, Wen-Wei; Cai, Qing-Fu

1993-01-01

A satellite laser ranging system with an accuracy of the level of centimeter has been successfully developed at the Institute of Seismology, State Seismological Bureau with the cooperation of the Institute of Geodesy and Geophysics, Chinese Academy of Science. With significant improvements on the base of the second generation SLR system developed in 1985, ranging accuracy of the new system has been upgraded from 15 cm to 3-4 cm. Measuring range has also been expanded, so that the ETALON satellite with an orbit height of 20,000 km launched by the former U.S.S.R. can now be tracked. Compared with the 2nd generation SLR system, the newly developed system has the following improvements. A Q modulated laser is replaced by a mode-locked YAG laser. The new device has a pulse width of 150 ps and a repetition rate of 1-4 pps. A quick response photomultiplier has been adopted as the receiver for echo; for example, the adoption of the MCP tube has obviously reduced the jitter error of the transit time and has improved the ranging accuracy. The whole system is controlled by an IBM PC/XT Computer to guide automatic tracking and measurement. It can carry out these functions for satellite orbit calculation, real-time tracking and adjusting, data acquisition and the preprocessed of observing data, etc. The automatization level and reliability of the observation have obviously improved.

Short range part of the NN interaction: Equivalent local potentials from quark exchange kernels

International Nuclear Information System (INIS)

Suzuk, Y.; Hecht, K.T.

1983-01-01

To focus on the nature of the short range part of the NN interaction, the intrinsically nonlocal interaction among the quark constituents of colorless nucleons is converted to an equivalent local potential using resonating group kernels which can be evaluated in analytic form. The WKB approximation based on the Wigner transform of the nonlocal kernels has been used to construct the equivalent potentials without recourse to the long range part of the NN interaction. The relative importance of the various components of the exchange kernels can be examined: The results indicate the importance of the color magnetic part of the exchange kernel for the repulsive part in the (ST) = (10), (01) channels, in particular since the energy dependence of the effective local potentials seems to be set by this term. Large cancellations of color Coulombic and quark confining contributions, together with the kinetic energy and norm exchange terms, indicate that the exact nature of the equivalent local potential may be sensitive to the details of the parametrization of the underlying quark-quark interaction. The equivalent local potentials show some of the characteristics of the phenomenological short range terms of the Paris potential

Application of air pollution dispersion modeling for source-contribution assessment and model performance evaluation at integrated industrial estate-Pantnagar

Energy Technology Data Exchange (ETDEWEB)

Banerjee, T., E-mail: tirthankaronline@gmail.com [Department of Environmental Science, G.B. Pant University of Agriculture and Technology, Pantnagar, U.S. Nagar, Uttarakhand 263 145 (India); Barman, S.C., E-mail: scbarman@yahoo.com [Department of Environmental Monitoring, Indian Institute of Toxicology Research, Post Box No. 80, Mahatma Gandhi Marg, Lucknow-226 001, Uttar Pradesh (India); Srivastava, R.K., E-mail: rajeevsrivastava08@gmail.com [Department of Environmental Science, G.B. Pant University of Agriculture and Technology, Pantnagar, U.S. Nagar, Uttarakhand 263 145 (India)

2011-04-15

Source-contribution assessment of ambient NO{sub 2} concentration was performed at Pantnagar, India through simulation of two urban mathematical dispersive models namely Gaussian Finite Line Source Model (GFLSM) and Industrial Source Complex Model (ISCST-3) and model performances were evaluated. Principal approaches were development of comprehensive emission inventory, monitoring of traffic density and regional air quality and conclusively simulation of urban dispersive models. Initially, 18 industries were found responsible for emission of 39.11 kg/h of NO{sub 2} through 43 elevated stacks. Further, vehicular emission potential in terms of NO{sub 2} was computed as 7.1 kg/h. Air quality monitoring delineates an annual average NO{sub 2} concentration of 32.6 {mu}g/m{sup 3}. Finally, GFLSM and ISCST-3 were simulated in conjunction with developed emission inventories and existing meteorological conditions. Models simulation indicated that contribution of NO{sub 2} from industrial and vehicular source was in a range of 45-70% and 9-39%, respectively. Further, statistical analysis revealed satisfactory model performance with an aggregate accuracy of 61.9%. - Research highlights: > Application of dispersion modeling for source-contribution assessment of ambient NO{sub 2}. > Inventorization revealed emission from industry and vehicles was 39.11 and 7.1 kg/h. > GFLSM revealed that vehicular pollution contributes a range of 9.0-38.6%. > Source-contribution of 45-70% was found for industrial emission through ISCST-3. > Aggregate performance of both models shows good agreement with an accuracy of 61.9%. - Development of industrial and vehicular inventory in terms of ambient NO{sub 2} for model simulation at Pantnagar, India and model validation revealed satisfactory outcome.

Ultra-wideband ranging precision and accuracy

International Nuclear Information System (INIS)

MacGougan, Glenn; O'Keefe, Kyle; Klukas, Richard

2009-01-01

This paper provides an overview of ultra-wideband (UWB) in the context of ranging applications and assesses the precision and accuracy of UWB ranging from both a theoretical perspective and a practical perspective using real data. The paper begins with a brief history of UWB technology and the most current definition of what constitutes an UWB signal. The potential precision of UWB ranging is assessed using Cramer–Rao lower bound analysis. UWB ranging methods are described and potential error sources are discussed. Two types of commercially available UWB ranging radios are introduced which are used in testing. Actual ranging accuracy is assessed from line-of-sight testing under benign signal conditions by comparison to high-accuracy electronic distance measurements and to ranges derived from GPS real-time kinematic positioning. Range measurements obtained in outdoor testing with line-of-sight obstructions and strong reflection sources are compared to ranges derived from classically surveyed positions. The paper concludes with a discussion of the potential applications for UWB ranging

Sources and characteristics of summertime organic aerosol in the Colorado Front Range: perspective from measurements and WRF-Chem modeling

Directory of Open Access Journals (Sweden)

R. Bahreini

2018-06-01

Full Text Available The evolution of organic aerosols (OAs and their precursors in the boundary layer (BL of the Colorado Front Range during the Front Range Air Pollution and Photochemistry Éxperiment (FRAPPÉ, July–August 2014 was analyzed by in situ measurements and chemical transport modeling. Measurements indicated significant production of secondary OA (SOA, with enhancement ratio of OA with respect to carbon monoxide (CO reaching 0.085±0.003 µg m−3 ppbv−1. At background mixing ratios of CO, up to  ∼  1.8 µg m−3 background OA was observed, suggesting significant non-combustion contribution to OA in the Front Range. The mean concentration of OA in plumes with a high influence of oil and natural gas (O&G emissions was  ∼  40 % higher than in urban-influenced plumes. Positive matrix factorization (PMF confirmed a dominant contribution of secondary, oxygenated OA (OOA in the boundary layer instead of fresh, hydrocarbon-like OA (HOA. Combinations of primary OA (POA volatility assumptions, aging of semi-volatile species, and different emission estimates from the O&G sector were used in the Weather Research and Forecasting model coupled with Chemistry (WRF-Chem simulation scenarios. The assumption of semi-volatile POA resulted in greater than a factor of 10 lower POA concentrations compared to PMF-resolved HOA. Including top-down modified O&G emissions resulted in substantially better agreements in modeled ethane, toluene, hydroxyl radical, and ozone compared to measurements in the high-O&G-influenced plumes. By including emissions from the O&G sector using the top-down approach, it was estimated that the O&G sector contributed to  <  5 % of total OA, but up to 38 % of anthropogenic SOA (aSOA in the region. The best agreement between the measured and simulated median OA was achieved by limiting the extent of biogenic hydrocarbon aging and consequently biogenic SOA (bSOA production. Despite a lower production of bSOA in

Hematology and serum chemistry reference ranges of free-ranging moose (Alces Alces) in Norway

OpenAIRE

Rostal, Melinda K.; Evans, Alina L.; Solberg, Erling L.; Arnemo, Jon Martin

2012-01-01

This article is also available here: http://www.jwildlifedis.org/ Baseline reference ranges of serum chemistry and hematology data can be important indicators for the status of both individuals or populations of wild animals that are affected by emerging pathogens, toxicants, or other causes of disease. Frequently, reference ranges for these values are not available for wildlife species or subspecies. We present hematologic and serum chemistry reference ranges for moose (Alces ...

Prediction ranges. Annual review

Energy Technology Data Exchange (ETDEWEB)

Parker, J.C.; Tharp, W.H.; Spiro, P.S.; Keng, K.; Angastiniotis, M.; Hachey, L.T.

1988-01-01

Prediction ranges equip the planner with one more tool for improved assessment of the outcome of a course of action. One of their major uses is in financial evaluations, where corporate policy requires the performance of uncertainty analysis for large projects. This report gives an overview of the uses of prediction ranges, with examples; and risks and uncertainties in growth, inflation, and interest and exchange rates. Prediction ranges and standard deviations of 80% and 50% probability are given for various economic indicators in Ontario, Canada, and the USA, as well as for foreign exchange rates and Ontario Hydro interest rates. An explanatory note on probability is also included. 23 tabs.

Foraminiferal Range Expansions: The Mediterranean Sea as a natural laboratory for climate induced invasions

Science.gov (United States)

Hortense Mouanga, Gloria; Langer, Martin R.

2015-04-01

Climate change and biological invasions are key processes that modify biodiversity. One of the most severely affected areas of global change is the Mediterranean Sea, where global warming and the opening of the Suez Canal triggered a mass invasion of tropical Red Sea taxa into Mediterranean territories. Climate models prognosticate that the Mediterranean Sea will be one of the most affected ocean regions and may thus serve as a natural laboratory of future global changes. Among the key taxa that are rapidly expanding their latitudinal range in the Mediterranean Sea are symbiont-bearing foraminifera of the genus Amphistegina. Their range expansion strongly correlates with rising sea surface temperatures and mirrors processes of global change. Amphisteginid foraminifera are among the most prolific foraminiferal species and contribute significantly to shallow-water carbonate sediments. Given their prominent environmental role, rapid biogeographic range expansion, and impact on native ecosystems, amphisteginid range expansion and invasion into new territory are likely to trigger changes in ecosystem functioning. Among the uncertainties, it is not known whether all parts of the Mediterranean will be affected equally and to what extent amphisteginid invasions will impact native biotas. We have initiated a new baseline study to explore the effects of invasive amphisteginids on native foraminiferal biotas and to monitor expansion rates and effects on ecosystem functioning along the current range expansion front. We will present new data on recent shift along the range expansion front and discuss cascading effects on community structures and species richness of native foraminiferal biotas. The magnitude and effects that climate change will have on the Mediterranean foraminiferal faunas may ultimately serve as an example of what would happen along expansion fronts in global oceans.

One-loop contributions to neutral Higgs decay h→μτ

International Nuclear Information System (INIS)

Phan, K. H.; Hung, H.T.; Hue, L.T.

2016-01-01

In calculating one-loop contributions to amplitudes of the lepton-flavor violating decays of the neutral Higgses (LFVHD) to different flavor charged leptons, the analytic expressions can be written in term of Passarino–Veltman functions. Then, they can be computed numerically by LoopTools [1]. Another approach is using suitable analytic expressions established for just this particular case. We compare numerical results obtained from LoopTools and those computed by different expressions that have been applied recently. Then we derive the preferable ones that are applicable for large ranges of free parameters introduced in extensions of the standard model. For illustration, the LFVHD in a simple model, which has been discussed recently, will be investigated more precisely.

Binding of chemical warfare agent simulants as guests in a coordination cage: contributions to binding and a fluorescence-based response.

Science.gov (United States)

Taylor, Christopher G P; Piper, Jerico R; Ward, Michael D

2016-05-07

Cubic coordination cages act as competent hosts for several alkyl phosphonates used as chemical warfare agent simulants; a range of cage/guest structures have been determined, contributions to guest binding analysed, and a fluorescent response to guest binding demonstrated.

Some new contributions to neutrinoless double β-decay in an SU(2)xU(1) model

International Nuclear Information System (INIS)

Escobar, C.O.

1982-11-01

An SU(2) x U(1) model having both Dirac and Majorana mass terms for the neutrinos, with an extended Higgs sector without natural flavor conservation is considered. Under these conditions, it is shown that for a certain range of the mass parameters of the model, some new contributions become important for the neutrinoless double β-decay (ββ)oν. (Author) [pt

Low-energy modes and medium-range correlated motions in Pd79Ge21 alloy glass

International Nuclear Information System (INIS)

Shibata, Kaoru; Mizuseki, Hiroshi; Suzuki, Kenji

1993-01-01

It is well known that there are excess modes over the sound wave in low energy region below about 10 meV in glass materials, which do not exist in corresponding crystalline materials. We examined the low energy modes in a Pd 79 Ge 21 alloys glass by means of inelastic neutron scattering. Measurements were performed on the crystal analyzer type time-of-flight spectrometer LAM-40 with PG(002) and Ge(311) analyzer mirror, which is installed at KENS. The dynamic structure factor S(Q,ω) was obtained over the wide momentum range from 0.5 to 5.2A -1 . The measured S(Q,ω)'s have almost same momentum (Q) dependence at each energy (ℎω) in the energy range from 2.0 to 8.0 meV. In the energy region below 3 meV, we found a small shoulder peak at Q = 1.7A -1 in the momentum dependence of S(Q,ω). It corresponds to a prepeak in S(Q). Therefore it is concluded that the low energy modes in Pd 79 Ge 21 alloy glass is mainly contributed from medium-range correlated motions in the cluster consisting of a few chemical short-range structure units of Pd 6 Ge trigonal prism. (author)

Estimating the per-capita contribution of habitats and pathways in a migratory network: A modelling approach

Science.gov (United States)

Wiederholt, Ruscena; Mattsson, Brady J.; Thogmartin, Wayne E.; Runge, Michael C.; Diffendorfer, Jay E.; Erickson, Richard A.; Federico, Paula; Lopez-Hoffman, Laura; Fryxell, John; Norris, D. Ryan; Sample, Christine

2018-01-01

Every year, migratory species undertake seasonal movements along different pathways between discrete regions and habitats. The ability to assess the relative demographic contributions of these different habitats and pathways to the species’ overall population dynamics is critical for understanding the ecology of migratory species, and also has practical applications for management and conservation. Metrics for assessing habitat contributions have been well-developed for metapopulations, but an equivalent metric is not currently available for migratory populations. Here, we develop a framework for estimating the demographic contributions of the discrete habitats and pathways used by migratory species throughout the annual cycle by estimating the per capita contribution of cohorts using these locations. Our framework accounts for seasonal movements between multiple breeding and non-breeding habitats and for both resident and migratory cohorts. We illustrate our framework using a hypothetical migratory network of four habitats, which allows us to better understand how variations in habitat quality affect per capita contributions. Results indicate that per capita contributions for any habitat or pathway are dependent on habitat-specific survival probabilities in all other areas used as part of the migratory circuit, and that contribution metrics are spatially linked (e.g. reduced survival in one habitat also decreases the contribution metric for other habitats). Our framework expands existing theory on the dynamics of spatiotemporally structured populations by developing a generalized approach to estimate the habitat- and pathway-specific contributions of species migrating between multiple breeding and multiple non-breeding habitats for a range of life histories or migratory strategies. Most importantly, it provides a means of prioritizing conservation efforts towards those migratory pathways and habitats that are most critical for the population viability of

Factors Contributing Decreased Performance Of Slow Learners

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Dr. L. Kannan

2015-03-01

Full Text Available Back ground Even experienced teaching faculty and administrators can be challenged by learners who have not able to perform up to expected need in their annual performance of their students these students are called as slow learnersStruggle learners. There should be a designed study to foster discussion about diagnosing particular problems that contribute with meeting objectives of slow learners. Methodology The study was performed on the entire current first year of Medical students were all the three internal assessments of 250 students performance is taken in to consideration for the study. This study is of cross section type.After obtaining the list of all students marks in internal examination from medical education unit supporting mentors are contacted to meet the students and confidentiality is maintained throughout the study. After obtaining informed consent a questionnaire was administered to the students by the investigator. The questionnaire contains the following sections. Section I will be on the background characteristics of the student name age sex type of family. Section II will be on the details of their learning capabilities. Section III will focus on the awareness of the slow learners in which the precipitating factors contributing to them. Results The prevalence of slow learners as low achievers were contributed to be 32.4 percentages.The performance of the students is based on combination of all three internal assessment marks including theory and practical performance. In this the students age ranges from 17 to 21 years the mean age of student was contributed to be 17.81 and majority of the students were in the age group of 18 years which contributed to be 16867.2.In the present study majority were males 13252.8 compared to females 11847.2.but when study is compared to percentage of attendance majority of the individual 15177 scored more than 50 percentage of marks have more than 80 percentage of attendance but when

Retuning Rieske-type Oxygenases to Expand Substrate Range

Energy Technology Data Exchange (ETDEWEB)

Mohammadi, Mahmood; Viger, Jean-François; Kumar, Pravindra; Barriault, Diane; Bolin, Jeffrey T.; Sylvestre, Michel (INRS); (Purdue)

2012-09-17

Rieske-type oxygenases are promising biocatalysts for the destruction of persistent pollutants or for the synthesis of fine chemicals. In this work, we explored pathways through which Rieske-type oxygenases evolve to expand their substrate range. BphAE{sub p4}, a variant biphenyl dioxygenase generated from Burkholderia xenovorans LB400 BphAE{sub LB400} by the double substitution T335A/F336M, and BphAE{sub RR41}, obtained by changing Asn{sup 338}, Ile{sup 341}, and Leu{sup 409} of BphAE{sub p4} to Gln{sup 338}, Val{sup 341}, and Phe{sup 409}, metabolize dibenzofuran two and three times faster than BphAE{sub LB400}, respectively. Steady-state kinetic measurements of single- and multiple-substitution mutants of BphAE{sub LB400} showed that the single T335A and the double N338Q/L409F substitutions contribute significantly to enhanced catalytic activity toward dibenzofuran. Analysis of crystal structures showed that the T335A substitution relieves constraints on a segment lining the catalytic cavity, allowing a significant displacement in response to dibenzofuran binding. The combined N338Q/L409F substitutions alter substrate-induced conformational changes of protein groups involved in subunit assembly and in the chemical steps of the reaction. This suggests a responsive induced fit mechanism that retunes the alignment of protein atoms involved in the chemical steps of the reaction. These enzymes can thus expand their substrate range through mutations that alter the constraints or plasticity of the catalytic cavity to accommodate new substrates or that alter the induced fit mechanism required to achieve proper alignment of reaction-critical atoms or groups.

Long-Term Cognitive Outcomes of Birth Asphyxia and the Contribution of Identified Perinatal Asphyxia to Cerebral Palsy.

Science.gov (United States)

Pappas, Athina; Korzeniewski, Steven J

2016-09-01

Neonatal encephalopathy among survivors of presumed perinatal asphyxia is recognized as an important cause of cerebral palsy (CP) and neuromotor impairment. Recent studies suggest that moderate to severe neonatal encephalopathy contributes to a wide range of neurodevelopmental and cognitive impairments among survivors with and without CP. Nearly 1 of every 4 to 5 neonates treated with hypothermia has or develops CP. Neonatal encephalopathy is diagnosed in only approximately 10% of all cases. This article reviews the long-term cognitive outcomes of children with presumed birth asphyxia and describes what is known about its contribution to CP. Copyright © 2016 Elsevier Inc. All rights reserved.

Relative source contributions for perchlorate exposures in a lactating human cohort

Energy Technology Data Exchange (ETDEWEB)

Kirk, Andrea B. [University of North Texas Health Sciences Center (United States); Dyke, Jason V. [University of Texas at Arlington (United States); Ohira, Shin-Ichi [Kumamoto University (Japan); Dasgupta, Purnendu K., E-mail: Dasgupta@uta.edu [University of Texas at Arlington (United States)

2013-01-15

Perchlorate is an iodine-uptake inhibitor and common contaminant of food and drinking water. Understanding the amount of perchlorate exposure occurring through non-water sources is essential for accurate estimates of human exposure levels, and establishment of drinking water limits for this pervasive contaminant. The study objective was to determine the amount of perchlorate intake derived from diet rather than water. Subjects provided drinking water samples, detailed fluid-intake records, 24 h urine collections and four milk samples for nine days. Samples were analyzed for perchlorate by isotope dilution ion chromatography–tandem mass spectrometry. Amounts of perchlorate derived from drinking water and dietary sources were calculated for each individual. Water of local origin was found to contribute a minor fraction of perchlorate intake. Estimated fraction intake from drinking water ranged from 0 to 36%. The mean and median dose of perchlorate derived from non-water sources by lactating women was 0.18 μg/kg/day (range: 0.06 to 0.36 μg/kg/day.) Lactating women consumed more fluid (mean 2.424 L/day) than has been assumed in recent risk assessments for perchlorate. The data reported here indicate that lactating women may be exposed to perchlorate through dietary sources at markedly higher levels than estimated previously. Exposures to perchlorate from non-water sources may be higher than recent estimates, including those used to develop drinking water standards. - Highlights: ► Residence in an area with perchlorate-contaminated water may be a poor predictor of exposure. ► Exposures to perchlorate from food are likely underestimated. ► The relative contributions for human perchlorate exposures should be weighted more heavily towards non-water sources.

First full dynamic range calibration of the JUNGFRAU photon detector

Science.gov (United States)

Redford, S.; Andrä, M.; Barten, R.; Bergamaschi, A.; Brückner, M.; Dinapoli, R.; Fröjdh, E.; Greiffenberg, D.; Lopez-Cuenca, C.; Mezza, D.; Mozzanica, A.; Ramilli, M.; Ruat, M.; Ruder, C.; Schmitt, B.; Shi, X.; Thattil, D.; Tinti, G.; Vetter, S.; Zhang, J.

2018-01-01

The JUNGFRAU detector is a charge integrating hybrid silicon pixel detector developed at the Paul Scherrer Institut for photon science applications, in particular for the upcoming free electron laser SwissFEL. With a high dynamic range, analogue readout, low noise and three automatically switching gains, JUNGFRAU promises excellent performance not only at XFELs but also at synchrotrons in areas such as protein crystallography, ptychography, pump-probe and time resolved measurements. To achieve its full potential, the detector must be calibrated on a pixel-by-pixel basis. This contribution presents the current status of the JUNGFRAU calibration project, in which a variety of input charge sources are used to parametrise the energy response of the detector across four orders of magnitude of dynamic range. Building on preliminary studies, the first full calibration procedure of a JUNGFRAU 0.5 Mpixel module is described. The calibration is validated using alternative sources of charge deposition, including laboratory experiments and measurements at ESRF and LCLS. The findings from these measurements are presented. Calibrated modules have already been used in proof-of-principle style protein crystallography experiments at the SLS. A first look at selected results is shown. Aspects such as the conversion of charge to number of photons, treatment of multi-size pixels and the origin of non-linear response are also discussed.

Effects of short range ΔN interaction on observables of the πNN system

International Nuclear Information System (INIS)

Alexandrou, C.; Blankleider, B.

1990-01-01

The inadequacy of standard few-body approaches in describing the πNN system has motivated searches for the responsible missing mechanism. In the case of πd scattering, it has recently been asserted that an additional short range ΔN interaction can account for essentially all the discrepancies between a few-body calculation and experimental data. This conclusion, however, has been based on calculations where a phenomenological ΔN interaction is added only in Born term to background few-body amplitudes. In the present work we investigate the effect of including such a ΔN interaction to all orders within a unitary few-body calculation of the πNN system. Besides testing the validity of adding the ΔN interaction in Born term in πd scattering, our fully coupled approach also enables us to see the influence of the same ΔN interaction on the processes NN→πd and NN→NN. For πd elastic scattering, we find that the higher order ΔN interaction terms can have as much influence on πd observables as the lowest order contribution alone. Moreover, we find that the higher order contributions tend to cancel the effect obtained by adding the ΔN interaction in Born term only. The effect of the same ΔN interaction on NN→πd and NN→NN appears to be as significant as in πd→πd, suggesting that future investigations of the short range ΔN interaction should be done in the context of the fully coupled πNN system

Energy contribution from non-breastmilk items in low-income Guatemalan infantsin their sixth month of life

Directory of Open Access Journals (Sweden)

Marieke Vossenaar

2015-03-01

Full Text Available Objective. To examine the nature and energy contribution of complementary feeding in breastfed infants in their sixth month of life, and the prevalence of the use of bottles as a delivery method. Materials and methods. We recruited 156 breastfeeding infants at a health clinic in metropolitan Quetzaltenango, Guatemala. A previous-day recall was performed. Results. Sixty nine mothers (44% reported offering items other than breastmilk. The median contribution of energy from complementary foods among infants with mixed feeding (n=66 was 197 kcal/day (interquartile range [IQR] 49-353. The median energy contribution of formula or cow’s milk among consumers (n=39 was 212 kcal/day (IQR 84-394. Bottles were used on the previous day by 55 (80% of the 69 mothers not offering exclusive breastfeeding. Conclusions. Premature introduction of non-breastmilk items is commonly practiced in feeding Guatemalan infants. Adherence to the internationally recognized guidelines for early infant feeding should be an intervention priority for this population.

Gallium interstitial contributions to diffusion in gallium arsenide

Science.gov (United States)

Schick, Joseph T.; Morgan, Caroline G.

2011-09-01

A new diffusion path is identified for gallium interstitials, which involves lower barriers than the barriers for previously identified diffusion paths [K. Levasseur-Smith and N. Mousseau, J. Appl. Phys. 103, 113502 (2008), P. A. Schultz and O. A. von Lilienfeld, Modelling and Simulation in Materials Science and Engineering 17, 084007 (2009)] for the charge states which dominate diffusion over most of the available range of Fermi energies. This path passes through the ⟨110⟩ gallium-gallium split interstitial configuration, and has a particularly low diffusion barrier of 0.35 eV for diffusion in the neutral charge state. As a part of this work, the character of the charge states for the gallium interstitials which are most important for diffusion is investigated, and it is shown that the last electron bound to the neutral interstitial occupies a shallow hydrogenic bound state composed of conduction band states for the hexagonal interstitial and both tetrahedral interstitials. How to properly account for the contributions of such interstitials is discussed for density-functional calculations with a k-point mesh not including the conduction band edge point. Diffusion barriers for gallium interstitials are calculated in all the charge states which can be important for a Fermi level anywhere in the gap, q = 0, +1, +2, and +3, for diffusion via the ⟨110⟩ gallium-gallium split interstitial configuration and via the hexagonal interstitial configuration. The lowest activation enthalpies over most of the available range of Fermi energies are found to correspond to diffusion in the neutral or singly positive state via the ⟨110⟩ gallium-gallium split interstitial configuration. It is shown that several different charge states and diffusion paths contribute significantly for Fermi levels within 0.2 eV above the valence band edge, which may help to explain some of the difficulties [H. Bracht and S. Brotzmann, Phys. Rev. B 71, 115216 (2005)] which have been

Contribution of water dimer absorption to the millimeter and far infrared atmospheric water continuum

Science.gov (United States)

Scribano, Yohann; Leforestier, Claude

2007-06-01

We present a rigorous calculation of the contribution of water dimers to the absorption coefficient α(ν¯,T ) in the millimeter and far infrared domains, over a wide range (276-310K) of temperatures. This calculation relies on the explicit consideration of all possible transitions within the entire rovibrational bound state manifold of the dimer. The water dimer is described by the flexible 12-dimensional potential energy surface previously fitted to far IR transitions [C. Leforestier et al., J. Chem. Phys. 117, 8710 (2002)], and which was recently further validated by the good agreement obtained for the calculated equilibrium constant Kp(T) with experimental data [Y. Scribano et al., J. Phys. Chem. A. 110, 5411 (2006)]. Transition dipole matrix elements were computed between all rovibrational states up to an excitation energy of 750cm-1, and J =K=5 rotational quantum numbers. It was shown by explicit calculations that these matrix elements could be extrapolated to much higher J values (J=30). Transitions to vibrational states located higher in energy were obtained from interpolation of computed matrix elements between a set of initial states spanning the 0-750cm-1 range and all vibrational states up to the dissociation limit (˜1200cm-1). We compare our calculations with available experimental measurements of the water continuum absorption in the considered range. It appears that water dimers account for an important fraction of the observed continuum absorption in the millimeter region (0-10cm-1). As frequency increases, their relative contribution decreases, becoming small (˜3%) at the highest frequency considered ν¯=944cm-1.

Long-Range WindScanner System

DEFF Research Database (Denmark)

Vasiljevic, Nikola; Lea, Guillaume; Courtney, Michael

2016-01-01

The technical aspects of a multi-Doppler LiDAR instrument, the long-range WindScanner system, are presented accompanied by an overview of the results from several field campaigns. The long-range WindScanner system consists of three spatially-separated, scanning coherent Doppler LiDARs and a remote......-rangeWindScanner system measures the wind field by emitting and directing three laser beams to intersect, and then scanning the beam intersection over a region of interest. The long-range WindScanner system was developed to tackle the need for high-quality observations of wind fields on scales of modern wind turbine...

Uncapacitated facility location problems: contributions

Directory of Open Access Journals (Sweden)

Galvão Roberto Diéguez

2004-01-01

Full Text Available The objective of the present paper is to review my personal contributions in the field of uncapacitated facility location problems. These contributions took place throughout my academic career, from the time I was a Ph.D. student at Imperial College to the present day. They cover approximately 30 years, from 1973 to 2003; they address: algorithms developed for the p-median problem and for a general formulation of uncapacitated location problems; the study of dynamic location models; covering and hierarchical location problems; queuing-based probabilistic location models. The contributions encompass theoretical developments, computational algorithms and practical applications. All work took place in an academic environment, with the invaluable collaboration of colleagues (both in Brazil and abroad and research students at COPPE. Each section in the paper is dedicated to a topic that involves a personal contribution. Every one of them is placed within the context of the existing literature.

On Range of Skill

DEFF Research Database (Denmark)

Hansen, Thomas Dueholm; Miltersen, Peter Bro; Sørensen, Troels Bjerre

2008-01-01

size (and doubly exponential in its depth). We also provide techniques that yield concrete bounds for unbalanced game trees and apply these to estimate the Range of Skill of Tic-Tac-Toe and Heads-Up Limit Texas Hold'em Poker. In particular, we show that the Range of Skill of Tic-Tac-Toe is more than...

Protein adsorption on tailored substrates: long-range forces and conformational changes

Energy Technology Data Exchange (ETDEWEB)

Bellion, M; Santen, L [Department of Theoretical Physics, Saarland University, 66041 Saarbruecken (Germany); Mantz, H; Haehl, H; Quinn, A; Nagel, A; Gilow, C; Weitenberg, C; Schmitt, Y; Jacobs, K [Department of Experimental Physics, Saarland University, 66041 Saarbruecken (Germany)], E-mail: k.jacobs@physik.uni-saarland.de

2008-10-08

Adsorption of proteins onto solid surfaces is an everyday phenomenon that is not yet fully understood. To further the current understanding, we have performed in situ ellipsometry studies to reveal the adsorption kinetics of three different proteins, lysozyme, {alpha}-amylase and bovine serum albumin. As substrates we offer Si wafers with a controlled Si oxide layer thickness and a hydrophilic or hydrophobic surface functionalization, allowing the tailoring of the influence of short- and long-range interactions. Our studies show that not only the surface chemistry determines the properties of an adsorbed protein layer but also the van der Waals contributions of a composite substrate. We compare the experimental findings to results of a colloidal Monte Carlo approach that includes conformational changes of the adsorbed proteins induced by density fluctuations.

Free-range pigs foraging on Jerusalem artichokes (Helianthus tuberosus L.) – Effect of feeding strategy on growth, feed conversion and animal behaviour

DEFF Research Database (Denmark)

Kongsted, Anne Grete; Horsted, Klaus; Hermansen, John Erik

2013-01-01

The nutritional contributions from free-range foraging, growth, feed conversion and behaviour were investigated in 36 growing pigs foraging on Jerusalem artichokes (JA) and fed concentrates restrictedly (30% of energy recommendations) or ad libitum. Compared to the ad libitum fed pigs, the pigs fed...

Europe's contribution to implementation of a radiation protection system

International Nuclear Information System (INIS)

Lecomte, J.F.

2010-01-01

What is commonly referred to as a radiation protection system is a range of scientific considerations, principles and rules, the aim of which is to contribute to an appropriate level of protection of individuals and the environment against the harmful effects of exposure to ionising radiation, without excessively limiting desirable human activities which can be associated with such exposure (see ICRP Publication 103). This system is essentially based on an international consensus. The European level only concerns the Member States of the Union but it is crucial that it constitute the final, legally binding step prior to the definition of national regulations. The European radiation protection system (the EURATOM Treaty and its derived legislation) is presented below, not from the legal perspective but from a contextual viewpoint. Research activities are not discussed here. (author)

Short-Range Correlated Magnetic Core-Shell CrO₂/Cr₂O₃ Nanorods: Experimental Observations and Theoretical Considerations.

Science.gov (United States)

Gandhi, Ashish C; Li, Tai-Yue; Chan, Ting Shan; Wu, Sheng Yun

2018-05-09

With the evolution of synthesis and the critical characterization of core-shell nanostructures, short-range magnetic correlation is of prime interest in employing their properties to develop novel devices and widespread applications. In this regard, a novel approach of the magnetic core-shell saturated magnetization (CSSM) cylinder model solely based on the contribution of saturated magnetization in one-dimensional CrO₂/Cr₂O₃ core-shell nanorods (NRs) has been developed and applied for the determination of core-diameter and shell-thickness. The nanosized effect leads to a short-range magnetic correlation of ferromagnetic core-CrO₂ extracted from CSSM, which can be explained using finite size scaling method. The outcome of this study is important in terms of utilizing magnetic properties for the critical characterization of core-shell nanomagnetic materials.

Panel acoustic contribution analysis.

Science.gov (United States)

Wu, Sean F; Natarajan, Logesh Kumar

2013-02-01

Formulations are derived to analyze the relative panel acoustic contributions of a vibrating structure. The essence of this analysis is to correlate the acoustic power flow from each panel to the radiated acoustic pressure at any field point. The acoustic power is obtained by integrating the normal component of the surface acoustic intensity, which is the product of the surface acoustic pressure and normal surface velocity reconstructed by using the Helmholtz equation least squares based nearfield acoustical holography, over each panel. The significance of this methodology is that it enables one to analyze and rank relative acoustic contributions of individual panels of a complex vibrating structure to acoustic radiation anywhere in the field based on a single set of the acoustic pressures measured in the near field. Moreover, this approach is valid for both interior and exterior regions. Examples of using this method to analyze and rank the relative acoustic contributions of a scaled vehicle cabin are demonstrated.

Contributions to sampling statistics

CERN Document Server

Conti, Pier; Ranalli, Maria

2014-01-01

This book contains a selection of the papers presented at the ITACOSM 2013 Conference, held in Milan in June 2013. ITACOSM is the bi-annual meeting of the Survey Sampling Group S2G of the Italian Statistical Society, intended as an international  forum of scientific discussion on the developments of theory and application of survey sampling methodologies and applications in human and natural sciences. The book gathers research papers carefully selected from both invited and contributed sessions of the conference. The whole book appears to be a relevant contribution to various key aspects of sampling methodology and techniques; it deals with some hot topics in sampling theory, such as calibration, quantile-regression and multiple frame surveys, and with innovative methodologies in important topics of both sampling theory and applications. Contributions cut across current sampling methodologies such as interval estimation for complex samples, randomized responses, bootstrap, weighting, modeling, imputati...

Modelling of monovacancy diffusion in W over wide temperature range

International Nuclear Information System (INIS)

Bukonte, L.; Ahlgren, T.; Heinola, K.

2014-01-01