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See detailAnomalous 14N/15N ratio in comets 122P/1995 S1 (de Vico) and 153P/2002 C1 (Ikeya-Zhang)
Arpigny, Claude ULiege; Cochran, A. L.; Jehin, Emmanuel ULiege et al

in Bulletin of the American Astronomical Society (2003, May 01), 35

High-resolution (R 60,000) spectra of the Halley-type comet 122P/1995 S1 de Vico (Period 74 years) and the ``intermediate-period" comet 153P/2002 C1 Ikeya-Zhang (P 370 yr) were obtained with the 2DCoude ... [more ▼]

High-resolution (R 60,000) spectra of the Halley-type comet 122P/1995 S1 de Vico (Period 74 years) and the ``intermediate-period" comet 153P/2002 C1 Ikeya-Zhang (P 370 yr) were obtained with the 2DCoude spectrograph at the 2.7-m Harlan J. Smith telescope of the McDonald Observatory. These comets were within 1 AU from the Sun (0.66 and 0.92 AU, respectively). The spectra display CN (0,0) bands indicating an anomalous [SUP]14[/SUP]N/[SUP]15[/SUP]N isotope ratio, in the sense that it is close to half the value in Earth's atmosphere (the so-called ``Solar system value") and about half that obtained in comet Hale-Bopp from sub-millimeter measurements on HCN, generally believed to be the main parent of CN. Similar conclusions had been reached for C/1995 O1 (Hale-Bopp), an ``old long-period", and for C/2000 WM1 (LINEAR), a ``young long-period" comet. As suggested by Arpigny et al. (2003), this apparent abundance anomaly points towards the existence of other unknown parent(s) of CN, with an even higher [SUP]15[/SUP]N excess. Organic compounds like those found in interplanetary dust particles (IDPs) are good candidates. The similarity between comets of different dynamical ages is pointed out. 1 Research Director FNRS (Belgium) 2 Research Associate FNRS (Belgium) [less ▲]

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See detailThe Anomalous 14N/15N Ratio in Comets 122P/1995 S1 (de Vico) and 153P/2002 C1 (Ikeya-Zhang)
Jehin, Emmanuel ULiege; Manfroid, Jean ULiege; Cochran, A. L. et al

in Astrophysical Journal (2004), 613(Letters), 161-164

High-resolution (R~60,000) spectra of the CN B[SUP]2[/SUP]Sigma[SUP]+[/SUP]-X[SUP]2[/SUP]Sigma[SUP]+[/SUP] (0, 0) band (near 3880 Å) in the Halley-type comet 122P/1995 S1 de Vico (with a period of 74 yr ... [more ▼]

High-resolution (R~60,000) spectra of the CN B[SUP]2[/SUP]Sigma[SUP]+[/SUP]-X[SUP]2[/SUP]Sigma[SUP]+[/SUP] (0, 0) band (near 3880 Å) in the Halley-type comet 122P/1995 S1 de Vico (with a period of 74 yr) and the ``intermediate-period'' comet 153P/2002 C1 Ikeya-Zhang (P~370 yr) were obtained with the 2dcoudé spectrograph at the 2.7 m Harlan J. Smith telescope of the McDonald Observatory. The comets were within 1 AU from the Sun (0.66 and 0.92 AU, respectively) at the time of the observations. While the measured [SUP]12[/SUP]C/[SUP]13[/SUP]C isotope ratios of both comets (90+/-10 and 90+/-25, respectively) are in very good agreement with the solar system value, the [SUP]14[/SUP]N/[SUP]15[/SUP]N ratios (140+/-20 and 170+/-50, respectively) are approximately half the value in Earth's atmosphere. The similarity is striking between these ratios and those obtained recently for two other long-period Oort Cloud comets, C/1995 O1 (Hale-Bopp) and C/2000 WM1 (LINEAR). While these optical determinations of [SUP]14[/SUP]N/[SUP]15[/SUP]N are consistent with each other, they disagree with those obtained in comet Hale-Bopp from submillimeter measurements of HCN, generally believed to be the main parent of CN. This puzzling difference points toward the existence of (an)other unknown parent(s) of CN, with an even higher [SUP]15[/SUP]N excess. Organic compounds like those found in interplanetary dust particles are good candidates. [less ▲]

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See detailAnomalous behavior of the irreversible magnetization and time relaxation in YBa(2)Cu(3)O(7) single crystals with splayed tracks
Silhanek, Alejandro ULiege; Niebieskikwiat, D.; Civale, L. et al

in Physical Review. B : Condensed Matter (1999), 60(18), 13189-13195

We have studied the angular dependence of the irreversible magnetization and its time relaxation in YBa(2)Cu(3)O(7) Single crystals with one or two families of columnar defects inclined with respect to ... [more ▼]

We have studied the angular dependence of the irreversible magnetization and its time relaxation in YBa(2)Cu(3)O(7) Single crystals with one or two families of columnar defects inclined with respect to the c axis. At high magnetic fields, the magnetization shows the usual maximum centered at the mean tracks' orientation and an associated minimum in the normalized relaxation rate. In contrast, at low fields we observe an anomalous local minimum in the magnetization and a maximum in the relaxation rate. We present a model to explain this anomaly based on the slowing down of the creep processes arising from the increase of the vortex-vortex interactions as the applied field is tilted away from the mean tracks' direction. [S0163-1829(99)11841-1]. [less ▲]

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See detailAnomalous behaviour in the diffusion of polyethylene oxide through dialysis membrane
Vignisse, Julie ULiege; Gustin, Audrey; Lespineux et al

Poster (2009, April 01)

Dialysis is a common technique adopted in biochemistry to purify biopharmaceutical drugs. This methodology is also of interest in macromolecular chemistry and pharmaceutical nanotechnology in order to ... [more ▼]

Dialysis is a common technique adopted in biochemistry to purify biopharmaceutical drugs. This methodology is also of interest in macromolecular chemistry and pharmaceutical nanotechnology in order to purify synthetic macromolecules and nanodrug carriers designed for drug delivery purposes. However, based on their original applications, the diffusion characteristic of the dialysis membrane is given in respect to the diffusion rate of globular proteins. So the diffusion capacity is function of molecular weight cut-off, i.e. corresponding to the maximum molecular weight of a globular macromolecule to be able to cross the membrane. The diffusion kinetics of synthetic macromolecules is expected to differ significantly from globular proteins due to at least the following differences : Specific relationship between hydrodynamic diameter and molecular weight, Flexibility Ionic density Solubility/miscibility/adsorption behaviour with the dialysis membrane Polymer chain entanglement above a critical concentration. In view to validate the application of this technique to purify synthetic macromolecules, we have compared the diffusion ability of neutral polyethyetylene oxide (PEO) standards or poly(dimethyl-aminoethyl-methacrylate) (PMADAM) to protein standards (human insulin and ovalbumin). [less ▲]

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See detailAnomalous Behaviour of a Protein During Sds/Page Corrected by Chemical Modification of Carboxylic Groups
Matagne, André ULiege; Joris, Bernard ULiege; Frère, Jean-Marie ULiege

in Biochemical Journal (1991), 280((Pt 2)), 553-6

The 29,000-Mr Actinomadura R39 beta-lactamase exhibited a remarkably low electrophoretic mobility on SDS/PAGE, yielding an Mr value almost twice that computed from the corresponding gene sequence. We ... [more ▼]

The 29,000-Mr Actinomadura R39 beta-lactamase exhibited a remarkably low electrophoretic mobility on SDS/PAGE, yielding an Mr value almost twice that computed from the corresponding gene sequence. We showed that chemical modification of the carboxylic groups of glutamic acid and aspartic acid residues restored a normal electrophoretic mobility and that the anomalous behaviour of that protein on SDS/PAGE was due to its very large negative charge at neutral pH. We also compared the behaviour of the same enzyme on gel filtration in the presence of SDS with those of other class A beta-lactamases (Mr approx. 30,000). These experiments suggested that the very low electrophoretic mobility of the Actinomadura R39 beta-lactamase upon SDS/PAGE was more probably due to a low degree of SDS binding rather than to an unusual shape of the SDS-protein complex. [less ▲]

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See detailAnomalous diffusion and non-monotonic relaxation processes in Ge-Se liquids
Yildirim, Can ULiege; Raty, Jean-Yves ULiege; Micoulaut, Matthieu

in Journal of Chemical Physics (2016), 144

We investigate the dynamical properties of liquid GexSe100−x as a function of Ge content by first-principles molecular dynamic simulations for a certain number of temperatures in the liquid state. The ... [more ▼]

We investigate the dynamical properties of liquid GexSe100−x as a function of Ge content by first-principles molecular dynamic simulations for a certain number of temperatures in the liquid state. The focus is set on ten compositions (where x ≤ 33%) encompassing the reported flexible to rigid and rigid to stressed-rigid transitions. We examine diffusion coefficients, diffusion activation energies, glassy relaxation behavior, and viscosity of these liquids from Van Hove correlation and intermediate scattering functions. At fixed temperature, all properties/functions exhibit an anomalous behavior with Ge content in the region 18%-22%, and provide a direct and quantitative link to the network rigidity. [less ▲]

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See detailANOMALOUS ELECTRON HEAT-TRANSPORT DRIVEN BY LOW-FREQUENCY ELECTROMAGNETIC TURBULENCE
Thoul, Anne ULiege; Similon, P.L.; Sudan, R.N.

in Physical Review Letters (1987), 59(13), 1448-1451

We consider the anomalous electron and heat transport in a tokamak plasma. The electrons are described by the nonlinear drift-kinetic equation. We analyze transport through the averaged response function ... [more ▼]

We consider the anomalous electron and heat transport in a tokamak plasma. The electrons are described by the nonlinear drift-kinetic equation. We analyze transport through the averaged response function in the presence of drift-Alfvén wave turbulence. In contrast to recent findings by Terry, Diamond, and Hahm, we conclude that magnetic fluctuations lead to a substantial transport of both parallel and perpendicular energies. The latter, previously neglected, is found to be significant and of the order of the test-particle diffusion. [less ▲]

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See detailANOMALOUS ELECTRON HEAT-TRANSPORT DRIVEN BY LOW-FREQUENCY ELECTROMAGNETIC TURBULENCE - REPLY
Thoul, Anne ULiege; Similon, P.L.; Sudan, R.N.

in Physical Review Letters (1988), 60(10), 967-967

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See detailAnomalous ESR behavior of carbon nanofilaments grown from palladium seeds
Breton, Y.; Verstraete, Matthieu ULiege; Fleurier, R. et al

in Carbon (2004), 42

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See detailAnomalous local magnetic field distribution and strong pinning in CaFe 1.94 Co 0.06 As 2 single crystals
Mandal, P.; Shaw, Gorky ULiege; Banerjee, S. S. et al

in Europhysics Letters [=EPL] (2012), 100(4), 47002

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See detailAnomalous missing-pT events at the CERN ppbar collider: The standard model re-examined
Cudell, Jean-René ULiege; Halzen, Francis; Hikasa, Ken*-ichi

in Physics Letters B (1985), 157

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See detailAnomalous Nitrogen Isotope Ratio in Comets
Arpigny, Claude ULiege; Jehin, Emmanuel ULiege; Manfroid, Jean ULiege et al

in Science (2003), 301

High-resolution spectra of the CN B[SUP]2[/SUP] Sigma[SUP]+[/SUP]-X[SUP]2[/SUP] Sigma[SUP]+[/SUP] (0,0) band at 390 nanometers yield isotopic ratios for comets C/1995 O1 (Hale-Bopp) and C/2000 WM1 (LINEAR ... [more ▼]

High-resolution spectra of the CN B[SUP]2[/SUP] Sigma[SUP]+[/SUP]-X[SUP]2[/SUP] Sigma[SUP]+[/SUP] (0,0) band at 390 nanometers yield isotopic ratios for comets C/1995 O1 (Hale-Bopp) and C/2000 WM1 (LINEAR) as follows: 165 +/- 40 and 115 +/- 20 for [SUP]12[/SUP]C/[SUP]13[/SUP]C, 140 +/- 35 and 140 +/- 30 for [SUP]14[/SUP]N/[SUP]15[/SUP]N. Our N isotopic measurements are lower than the terrestrial [SUP]14[/SUP]N/[SUP]15[/SUP]N = 272 and the ratio for Hale-Bopp from measurements of HCN, the presumed parent species of CN. This isotopic anomaly suggests the existence of other parent(s) of CN, with an even lower N isotopic ratio. Organic compounds like those found in interplanetary dust particles are good candidates. [less ▲]

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See detailAn anomalous nonlinear heat-conduction problem (improvement)
Beckers, Jean-Marie ULiege

in Mathematical & Computer Modelling (1990), 13(5), 89-92

A linear anomalous heat-flux problem is analysed from a stability point of view and a previous [Mathl Comput. Modelling 12(6), 671–672 (1989)] is improved. Then a non-linear problem proposed in the same ... [more ▼]

A linear anomalous heat-flux problem is analysed from a stability point of view and a previous [Mathl Comput. Modelling 12(6), 671–672 (1989)] is improved. Then a non-linear problem proposed in the same paper is partly resolved and numerically verified, which shows that only one stationary solution is stable to perturbations. [less ▲]

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See detailAnomalous OI-989 Å intensity profile: solving an old mystery.
Hubert, Benoît ULiege; Gérard, Jean-Claude ULiege; Shematovich, Valery I. et al

Poster (2012, December 06)

Sounding rocket measurements conducted in 1988 under high solar activity conditions had revealed that the intensity of the thermospheric OI emission at 989 Å presents an anomalous vertical profile ... [more ▼]

Sounding rocket measurements conducted in 1988 under high solar activity conditions had revealed that the intensity of the thermospheric OI emission at 989 Å presents an anomalous vertical profile. Observation presents an intensity much higher than what can be expected compared with theoretical results including the photochemical sources of excited oxygen and the radiative transfer of the photons of the OI-989 sextuplet especially above the exobase. Attempts were conducted to clarify the discrepancy by including the non-thermal O(3P) population that appears around the exobase and higher, and that can scatter Doppler-shifted photons of the line profile farther from the rest wavelength. All attempts based on detail modeling of the photochemical processes and radiative transfer revealed unable to account for the discrepancy. Recently the FUV and EUV solar flux has been obtained at very high spectral resolution with the SOHO-SUMER instrument, revealing a significant solar oxygen emission at 989 Å, i.e. a source of photons that had never been accounted for before. In this study, we compute the radiative transfer of the OI-989 Å multiplet including the photochemical sources of excited oxygen, the scattering of incident solar photons and the effect of non-thermal atoms. We find a good agreement with the previous sounding rocket observation, solving the old mystery. We also compare the model simulations with the observations of the STP-78 satellite to better determine the relative importance of the various parameters at work in the radiative transfer of the OI-989 Å multiplet. [less ▲]

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See detailANOMALOUS PERTURBATIVE TRANSPORT IN TOKAMAKS DUE TO DRIFT-ALVEN-WAVE TURBULENCE
Thoul, Anne ULiege; SIMILON, P. L.; SUDAN, R. N.

in Physics of Plasmas (1994), 1(3), 601-608

The method developed in Thoul, Similon, and Sudan [Phys. Plasmas 1, 579 (1994)] is used to calculate the transport due to drift-Alfven-wave turbulence, in which electromagnetic effects such as the ... [more ▼]

The method developed in Thoul, Similon, and Sudan [Phys. Plasmas 1, 579 (1994)] is used to calculate the transport due to drift-Alfven-wave turbulence, in which electromagnetic effects such as the fluttering of the magnetic field lines are important. Explicit expressions are obtained for all coefficients of the anomalous transport matrix relating particle and heat fluxes to density and temperature gradients in the plasma. Although the magnetic terms leave the transport by trapped electrons unaffected, they are important for the transport by circulating electrons. [less ▲]

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See detailANOMALOUS PERTURBATIVE TRANSPORT IN TOKAMAKS DUE TO DRIFT-WAVE TURBULENCE
Thoul, Anne ULiege

Doctoral thesis (1992)

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See detailANOMALOUS PERTURBATIVE TRANSPORT IN TOKAMAKS DUE TO DRIFT-WAVE TURBULENCE
Thoul, Anne ULiege; SIMILON, P. L.; SUDAN, R. N.

in Physics of Plasmas (1994), 1(3), 579-600

A new method for calculating the anomalous transport in tokamak plasmas is presented. The renormalized nonlinear plasma response function is derived using the direct-interaction approximation (DIA). A ... [more ▼]

A new method for calculating the anomalous transport in tokamak plasmas is presented. The renormalized nonlinear plasma response function is derived using the direct-interaction approximation (DIA). A complete calculation for the case of electrostatic drift-wave turbulence is presented. Explicit expressions for all coefficients of the anomalous transport matrix relating particle and heat fluxes to density and temperature gradients in the plasma are obtained. The anomalous transport matrix calculated using the DIA does not have the Onsager symmetry. As an example of application, the parameters of the Texas Experimental Tokamak (TEXT) [Nucl. Technol. Fusion 1, 479 (1981)] are used to evaluate all transport coefficients numerically, as well as the spectrum modulation. The relation between the theoretical results and the experimental data is discussed. Although this paper focuses on electron transport for simplicity, the method can also be used to calculate anomalous transport due to ion instabilities, such as the ion-temperature-gradient instability. [less ▲]

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See detailAnomalous pion decay in effective QCD at finite temperature
Blaschke, David; Jaminon, Martine ULiege; Kalinovsky, Yu. L. et al

in Nuclear Physics A (1995), 592

The width of the process π0 → γγ is calculated within effective QCD at finite temperature. We use two different effective models which describe chiral symmetry breaking and its restoration at finite ... [more ▼]

The width of the process π0 → γγ is calculated within effective QCD at finite temperature. We use two different effective models which describe chiral symmetry breaking and its restoration at finite temperature in SU(2)ƒ: (i) an effective lagrangian with a nonlocal separable interaction kernel, (ii) A- and B-scaledNJL lagrangians which implement the scale anomaly of QCD. We calculate the temperature dependences of the quark and pion masses as well as of the pion-park-antiquark coupling strength below and above the double quark mass threshold. At zero temperature we obtain a fairly good agreement with the experimental value for the decay width. The temperature dependence of the decay width is related to that of the pion mass. Γπ0 → γγ is enhanced in the vicinity of the Mott temperature (Mπ = 2mq) for the nonlocal as well as for the A-scaled model and suppressed for the B-scaled model. We compare our results with the SU(2) Nambu-Jona-Lasinio model which is contained as a limiting case in our approach. [less ▲]

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See detailAnomalous Pregnancies during Late Embryonic/Early Foetal Period in High Producing Dairy Cows.
Serrano, B.; Lopez-Gatius, F.; Hunter, R. et al

in Reproduction in Domestic Animals (2009), 44(4), 672-676

This study analyses anomalous cases of gestation ending in pregnancy loss during the early foetal period and their effect on progesterone and plasma pregnancy-associated glycoprotein-1 (PAG-1 ... [more ▼]

This study analyses anomalous cases of gestation ending in pregnancy loss during the early foetal period and their effect on progesterone and plasma pregnancy-associated glycoprotein-1 (PAG-1) concentrations. Data derived from a large-scale ultrasound pregnancy diagnosis programme in high producing dairy cows. Over a 3-year period (2004-2007), a very low incidence (0.5%: 15 of 3094) of anomalous pregnancies was recorded. The results revealed that the following anomalies were detected on days 35-41 of gestation in cows carrying singletons with one single corpus luteum: embryo death in eight cows (0.3%); and embryo in the uterine horn contralateral to the corpus luteum in seven cows (0.2%). All these animals suffered pregnancy loss during the early foetal period. In cows carrying dead embryos, no signs of conceptus degeneration were observed on pregnancy diagnosis. Amnion size (approximately 25 mm diameter) and uterine horn fluid contents were estimated to be similar to those of the normal pregnant cows in this period. In the contralateral gestations, live embryos were observed in all ultrasound checks before pregnancy loss. Uterine fluid contents increased in the two cows in which gestation continued for more than a week. In the cases of embryo death but not in those of contralateral gestation, a drop in PAG-1 levels was noted prior to pregnancy loss. Two cows carrying dead embryos increased with time allantoic fluid contents. The PAG-1 values increased with time in one cow bearing a dead embryo (from 2.31 to 6.79 ng/ml) and in two of the contralateral gestations (from 1.66 to 2.33 ng/ml and from 0.39 to 6.79 ng/ml, respectively). Results of this study indicate that the foetal membranes continue to undergo some activity following embryo death, and that contralateral pregnancy may determine failure of the gestation process. [less ▲]

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See detailAnomalous temperature behavior of the resistivity in lightly doped manganites around a metal-insulator phase transition
Sergeenkov, S.; Ausloos, Marcel ULiege; Bougrine, Hassan ULiege et al

in JETP Letters (1999), 70(7), 481-487

An unusual temperature and concentration behavior of the resistivity ρ(T,x) in La0.7Ca0.3Mn1-xCuxO3 is observed at slight Cu doping (0 ≤x≤ 0.05). Namely, the introduction of copper results in a splitting ... [more ▼]

An unusual temperature and concentration behavior of the resistivity ρ(T,x) in La0.7Ca0.3Mn1-xCuxO3 is observed at slight Cu doping (0 ≤x≤ 0.05). Namely, the introduction of copper results in a splitting of the resistivity maximum around the metal-insulator transition temperature T0(x) into two differently evolving peaks. Unlike the original Cufree maximum, which steadily increases with doping, the second (satellite) peak remains virtually unchanged for x<xc, increases for x≥xc, and finally disappears at xm ≃ 2xc, with xc ≃ 0.03. The observed phenomenon is thought to arise from a competition between substitution-induced strengthening of the potential barriers (which hinder the charge hopping between neighboring Mn sites) and weakening of the kinetic energy of the carriers. The data are well fitted by assuming a nonthermal tunneling conductivity theory with randomly distributed hopping sites. © 1999 American Institute of Physics. [less ▲]

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