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See detailProton aurora in the cusp
Frey, H. U.; Mende, S. B.; Immel, T. J. et al

in Journal of Geophysical Research. Space Physics (2002), 107

Frequently, the Far Ultraviolet Instrument (FUV) on the Imager for Magnetopause-to-Aurora Global Exploration (IMAGE) spacecraft observes intense ultraviolet emission from a localized dayside region ... [more ▼]

Frequently, the Far Ultraviolet Instrument (FUV) on the Imager for Magnetopause-to-Aurora Global Exploration (IMAGE) spacecraft observes intense ultraviolet emission from a localized dayside region poleward of the general auroral oval location. This emission is especially distinct in the Doppler-shifted emission of hydrogen atoms produced by precipitating protons. We interpret this as a direct signature of proton precipitation into the cusp after reconnection of magnetospheric lobe field lines. This cusp signature appears only when the interplanetary magnetic field (IMF) has a positive northward B[SUB]z[/SUB] component. However, the intensity of the precipitation, and hence the intensity of UV emission, is not controlled by the magnitude of B[SUB]z[/SUB] but rather by the solar wind dynamic pressure. A statistical analysis of 18 cases observed in summer and fall 2000 shows good correlation between the UV intensity and the dynamic pressure and between the location in local time and the IMF B[SUB]y[/SUB] component. A quantitative analysis of observations from all three FUV subinstruments allows for an estimate of proton and electron energy fluxes during these times. In general, these estimates agree with results from in situ measurements by spacecraft and show that during these times, protons may contribute significantly to the overall energy deposition into the cusp. [less ▲]

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See detailThe Proton Formation from Methane by Dissociative Ionization in the Electron Energy range of 25-40 eV.
Locht, Robert ULg; Momigny, J.

in Chemical Physics (1980), 49

The proton formation by dissociative electroionization of methane has been investigated in the energy range of 25-40 eV. The kinetic energy-versus-appearance energy shows five different H+ producing ... [more ▼]

The proton formation by dissociative electroionization of methane has been investigated in the energy range of 25-40 eV. The kinetic energy-versus-appearance energy shows five different H+ producing processes respectively at (26.3+/0.2) eV, (26.9+/-0.2) eV, (29.4+/-0.3) eV, (32.7+/-0.2) eV and (35.7+/-0.5) eV. These critical energies are discussed in terms of different dissociation channels opened through predissociation of doubly excited states of CH4+. On the high energy side of the electron energy range in the present work, the proton would appear through the dissociation of the CH+ ion as an intermediate. [less ▲]

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See detailProton Induced Luminescence of Minerals
Calvo Del Castillo, Helena ULg; Millán, Asunción; Beneitez, Pedro et al

in Revista Mexicana de Física (2008), 54(2), 93-99

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See detailProton leak induced by reactive oxygen species produced during in vitro anoxia/reoxygenation in rat skeletal muscle mitochondria.
Navet, R.; Mouithys-mickalad, A.; Douette, P. et al

in Journal of Bioenergetics & Biomembranes (2006), 38

Superoxide anion generation and the impairment of oxidative phosphorylation yield were studied in rat skeletal muscle mitochondria submitted to anoxia/reoxygenation in vitro. Production of superoxide ... [more ▼]

Superoxide anion generation and the impairment of oxidative phosphorylation yield were studied in rat skeletal muscle mitochondria submitted to anoxia/reoxygenation in vitro. Production of superoxide anion was detected after several cycles of anoxia/reoxygenation. Concomitantly, a decrease of state 3 respiration and phosphorylation yield (ADP/O) were observed. The latter resulted from a proton leak. The presence of palmitic acid during anoxia/reoxygenation cycles led to a dose-dependent inhibition of superoxide anion production together with a partial protection of the ADP/O ratio measured after anoxia/reoxygenation. The ADP/O decrease was shown to be due to a permeability transition pore-sustained proton leak, as it was suppressed by cyclosporine A. The permeability transition pore activation was induced during anoxia/reoxygenation by superoxide anion, as it was cancelled by the spin trap (POBN), which scavenges superoxide anion and by palmitic acid, which induces mitochondrial uncoupling. It can be proposed that the palmitic acid-induced proton leak cancels the production of superoxide anion by mitochondria during anoxia/reoxygenation and therefore prevents the occurrence of the superoxide anion-induced permeability transition pore-mediated proton leak after anoxia/reoxygenation [less ▲]

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See detailProton MRS findings in migraine patients during visual stimulation
da Silva, H. M.; Magis, Delphine ULg; Balteau, Evelyne ULg et al

in Cephalalgia : An International Journal of Headache (2005, December), 25(12), 1196

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See detailProton partitioning between ATP synthase and uncoupling protein during cytochrome pathway state 3 respiration in tomato fruit mitochondria
Sluse, Francis ULg; Jarmuszkiewicz, W.; Almeida, A. M. et al

in Hofmeyr, J.; Rohwer, J. M.; Snoops, J. L. (Eds.) Biothermokinetic 2000 : Animating the cellular map (2000)

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See detailProton precipitation during substorm growth observed by IMAGE-FUV: a case study
Coumans, V.; Gérard, Jean-Claude ULg; Blockx, Caroline ULg et al

Poster (2006, March)

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See detailProton precipitation during transpolar auroral events: Observations with the IMAGE-FUV imagers
Hubert, Benoît ULg; Gérard, Jean-Claude ULg; Fuselier, S. A. et al

in Journal of Geophysical Research. Space Physics (2004), 109(A6), 06204

Several transpolar auroras have been observed with the IMAGE-Far Ultraviolet (FUV) imagers. The unique capability of the IMAGE-FUV experiment to image the proton and electron aurora simultaneously on a ... [more ▼]

Several transpolar auroras have been observed with the IMAGE-Far Ultraviolet (FUV) imagers. The unique capability of the IMAGE-FUV experiment to image the proton and electron aurora simultaneously on a global scale is used to study this phenomenon. A set of 12 transpolar aurora observed with IMAGE-FUV is studied. We find that the dynamics of the transpolar aurora in relation with the IMF is consistent with previously published studies. The proton energy flux in the transpolar structure is determined and compared with the electron contribution. The contribution of the proton aurora inside the transpolar arc is also considered at the global scale. On the average, transpolar structure contributes similar to10% of the total precipitation. We find that the proton precipitation carries similar to5% of the energy flux of the transpolar arc. In 11 of the 12 cases of transpolar events studied, a local brightening of the auroral Lyman-alpha emission is detected concurrently with the appearance of the transpolar structure. The intensification takes place at the nightside base of the transpolar arc, in the auroral oval. The duration of the intensification is variable but shorter than the lifetime of the transpolar arc. This study also suggests that the localized intensification is mainly due to an increase of the proton precipitation. [less ▲]

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See detailProton re-uptake partitioning between uncoupling protein and ATP synthase during benzohydroxamic acid-resistant state 3 respiration in tomato fruit mitochondria.
Jarmuszkiewicz, W.; Almeida, A.; Vercesi, A. et al

in Journal of Biological Chemistry (2000), 275(18), 13315-13320

The yield of oxidative phosphorylation in isolated tomato fruit mitochondria depleted of free fatty acids remains constant when respiratory rates are decreased by a factor of 3 by the addition of n-butyl ... [more ▼]

The yield of oxidative phosphorylation in isolated tomato fruit mitochondria depleted of free fatty acids remains constant when respiratory rates are decreased by a factor of 3 by the addition of n-butyl malonate. This constancy makes the determination of the contribution of the linoleic acid-induced energy-dissipating pathway by the ADP/O method possible. No decrease in membrane potential is observed in state 3 respiration with increasing concentration of n-butyl malonate, indicating that the rate of ATP synthesis is steeply dependent on membrane potential. Linoleic acid decreases the yield of oxidative phosphorylation in a concentration-dependent manner by a pure protonophoric process like that in the presence of FCCP. ADP/O measurements allow calculation of the part of respiration leading to ATP synthesis and the part of respiration sustained by the dissipative H(+) re-uptake induced by linoleic acid. Respiration sustained by this energy-dissipating process remains constant at a given LA concentration until more than 50% inhibition of state 3 respiration by n-butyl malonate is achieved. The energy dissipative contribution to oxygen consumption is proposed to be equal to the protonophoric activity of plant uncoupling protein divided by the intrinsic H(+)/O of the cytochrome pathway. It increases with linoleic acid concentration, taking place at the expense of ADP phosphorylation without an increase in the respiration. [less ▲]

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See detailProtoplast Fusion Technology For Somatic Hybridisation In Phaseolus
Geerts, P.; Druart, P.; Ochatt, S. et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2008), 12(1), 41-46

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See detailPrototype de banque de données pour la cartographie urbaine
Donnay, Jean-Paul ULg; Lahaye, Michel

in Merenne-Schoumaker, Bernadette (Ed.) Recherches de Géographie urbaine, Hommage au Prof. J.A. Sporck (1987)

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See detailLe prototype défiguré
Droixhe, Daniel ULg

in Koerner, K. (Ed.) Progress in linguistic historiography (1980)

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See detailA Prototype System for 3D Color Fusion and Mining of Multisensor/Spectral Imagery
Waxman, Allen M.; Verly, Jacques ULg; Fay, David A. et al

Conference (2001, August)

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See detailPrototyping of a Phase Change Material Heat Storage Device
Collette, Jean-Paul; Rochus, Pierre ULg; Peyrou-Lauga, Romain et al

in Proceedings of the 63rd International Astronautical Congress 1-5 Octobre 2012 (2012, October 05)

A new concept of Phase Change Materials (PCM) device has recently been developed to improve the thermal control of spacecraft. Two Phase Change Material candidates have been selected after extensive ... [more ▼]

A new concept of Phase Change Materials (PCM) device has recently been developed to improve the thermal control of spacecraft. Two Phase Change Material candidates have been selected after extensive testing of a set of available materials. Special attention has been paid to the hysteresis and ageing. In the design of the container, the thermal expansion of the PCM is a critical parameter that has been taken into consideration by two competing technologies. These designs have been tested: a prototype of PCM heat storage device has been effectively manufactured and tested under vacuum environment. 1D and 2D mathematical models have been developed. Conclusions are drawn to promote the use of PCM Heat Storage device in various space missions. [less ▲]

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See detailProuver l'inconscient
Gyemant, Maria ULg

Conference (2010, April 10)

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See detailProvasopressin expression by breast cancer cells: implications for growth and novel treatment strategies
Keegan, B. P.; Akerman, B. L.; Pequeux, Christel ULg et al

in Breast Cancer Research and Treatment (2006), 95(3), 265-277

The arginine vasopressin (AVP) gene is expressed in certain cancers such as breast cancer, where it is believed to act as an autocrine growth factor. However, little is known about the regulation of the ... [more ▼]

The arginine vasopressin (AVP) gene is expressed in certain cancers such as breast cancer, where it is believed to act as an autocrine growth factor. However, little is known about the regulation of the AVP protein precursor (proAVP) or AVP-mediated signaling in breast cancer and this study was undertaken to address some of the basic issues. The cultured cell lines examined (Mcf7, Skbr3, BT474, ZR75, Mcf10a) and human breast cancer tissue extract were found to express proAVP mRNA. Western analysis revealed multiple forms of proAVP protein were present in cell lysates, corresponding to those detected in human hypothalamus extracts. Monoclonal antibodies directed against different regions of proAVP bound to intact live Mcf7 and Skbr3 cells. Dexamethasone increased the amount of proAVP-associated glycopeptide (VAG) secreted by Skbr3 cells and a combination of dexamethasone, IBMX and 8br-cAMP increased cellular levels of VAG. Exogenous AVP (1, 10, and 100 nM) elevated phospho-ERK1/2 levels, and increased cell proliferation was observed in the presence of 10 nM AVP. Concurrent treatment with the V1a receptor antagonist SR49059 reduced the effects of AVP on proliferation in Mcf7 cells, and abolished it in Skbr3 cells. Results here show that proAVP components are found at the surface of Skbr3 and Mcf7 cells and are also secreted from these cells. In addition, they show that AVP promotes cancer cell growth, apparently through a V1-type receptor-mediated pathway and subsequent ERK1/2 activation. Thus, strategies for targeting proAVP should be examined for their effectiveness in diagnosing and treating breast cancer. [less ▲]

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See detailProvenance of Belgian Merovingian garnets by PIXE on IPNAS Cyclotron
Mathis, François ULg; Vrielynck, Olivier; Laclavetine, Kilian et al

Poster (2007)

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