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See detailDynamics of Dowstream Entry in Postal Markets
Gautier, Axel ULg

in Crew, Michael; Kleindorfer, Paul (Eds.) Liberalization of the Postal and Delivery Sector (2006)

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See detailDynamics of Elasto-Inertial Turbulence in Flows with Polymer Additives
Terrapon, Vincent ULg; Dubief, Yves; Soria, Julio

Scientific conference (2012, December 07)

Elasto-inertial turbulence is a new state of turbulence that may occur in certain viscoelastic flows, in particular flows with polymer additives. The dynamics of elasto-inertial turbulence is here ... [more ▼]

Elasto-inertial turbulence is a new state of turbulence that may occur in certain viscoelastic flows, in particular flows with polymer additives. The dynamics of elasto-inertial turbulence is here investigated numerically from the perspective of the coupling between polymer dynamics and flow structures. The resulting mechanism helps resolve a long standing controversy in the understanding of polymer drag reduction and explains the phenomenon of early turbulence, or onset of turbulence at lower Reynolds numbers than for Newtonian flows, previously observed in polymeric flows. In particular, we show that the introduction of small perturbations into the polymeric flow excites the unstable nature of the nonlinear advection term, resulting in the formation of sheets or cliffs of polymer stretch. These sheets of high polymer stretch, hosting a significant increase in extensional viscosity, create a strong local anisotropy, with a formation of local low-speed jet-like flow. The response of the flow is through pressure, whose role is to redistribute energy across components of momentum, resulting in the formation of waves, or trains of alternating rotational and straining motions. The mechanism shares some similarity with the Kelvin-Helmholtz instability, except that the thickness of these sheets is too close to the Kolmogorov scale for vortices to be created. Once triggered, EIT is self-sustained since the elastic instability creates the very velocity fluctuations it feeds upon. [less ▲]

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See detailDynamics of Elasto-Inertial Turbulence in Flows with Polymer Additives
Terrapon, Vincent ULg; Dubief, Yves; Soria, Julio

in Proceedings of the 8th International Symposium on Turbulence and Shear Flow Phenomena (TSFP-8) (2013, August 30)

The dynamics of elasto-inertial turbulence is investigated numerically from the perspective of the coupling between polymer dynamics and flow structures. In particular, direct numerical simulations of ... [more ▼]

The dynamics of elasto-inertial turbulence is investigated numerically from the perspective of the coupling between polymer dynamics and flow structures. In particular, direct numerical simulations of channel flow with Reynolds numbers ranging from 1000 to 6000 are used to study the formation and dynamics of elastic instabilities and their effects on the flow. Based on the splitting of the pressure into inertial and polymeric contributions, it is shown that the trains of cylindrical structures around sheets of high polymer extension that are characteristics to elasto-inertial turbulence are mostly driven by polymeric contributions. [less ▲]

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See detailDynamics of Environmental Migration
Gemenne, François ULg; Jäger, Jill; Entzinger, Han

Book published by Palgrave Macmillan (in press)

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See detailDynamics of erythropoietic recovery following bone marrow transplantation: role of marrow proliferative capacity and erythropoietin production in autologous versus allogeneic transplants.
Beguin, Yves ULg; Oris, Renée ULg; Fillet, Georges ULg

in Bone Marrow Transplantation (1993), 11(4), 285-92

The mechanisms of erythrocyte recovery after BMT are not known. We investigated the respective role of marrow function and erythropoietin production in 31 ABMT and 47 allogeneic BMT by analysing ... [more ▼]

The mechanisms of erythrocyte recovery after BMT are not known. We investigated the respective role of marrow function and erythropoietin production in 31 ABMT and 47 allogeneic BMT by analysing peripheral counts, serum erythropoietin levels, and serum transferrin receptor (TfR) levels which have been shown to be a quantitative measurement of erythropoiesis. Median times to complete neutrophil (25 vs 48 days, p < 0.0001) and platelet (45 vs 263 days, p < 0.001) recovery were faster after allogeneic BMT than ABMT, but complete erythrocyte recovery was slower (218 vs 101 days, p < 0.001). After ABMT, erythrocyte recovery paralleled that of neutrophils and platelets, and erythropoietin levels remained appropriate for the degree of anemia. After allogeneic BMT, erythrocytes developed independently of the other cell lines and defective erythropoietin production delayed recovery of adequate erythropoietic activity. This correlated with an alteration of renal function only in those patients remaining erythropoietin deficient beyond day 180. However, supranormal erythropoietin levels in interstitial pneumonia suggests that erythropoietin response to hypoxia is not abrogated. CMV infection could also affect erythropoiesis through erythropoietin production after ABMT as well as allogeneic BMT. It is concluded that after ABMT the development of erythropoiesis is determined by the overall marrow proliferative activity and erythropoietin plays only a facilitating role. After allogeneic BMT, erythropoiesis depends on erythropoietin levels which remain inadequate for prolonged periods of time. The results suggest that the administration of recombinant human erythropoietin could reduce transfusion requirements after BMT. [less ▲]

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See detailThe Dynamics of Fair Trade as a Mixed-form Market
Becchetti, Leonardo; Huybrechts, Benjamin ULg

in Journal of Business Ethics (2008), 81(4), 733-750

This article analyses the Fair Trade sector as a “mixed-form market,” i.e., a market in which different types of players (in this case, nonprofit, co-operative and for-profit organizations) coexist and ... [more ▼]

This article analyses the Fair Trade sector as a “mixed-form market,” i.e., a market in which different types of players (in this case, nonprofit, co-operative and for-profit organizations) coexist and compete. The purposes of this article are (1) to understand the factors that have led Fair Trade to become a mixed-form market and (2) to propose some trails to understand the market dynamics that result from the interactions between the different types of players. We start by defining briefly Fair Trade, its different dimensions (including the “fair” quality of the products) and its organizational landscape, focusing on the distinction between the pioneer “Alternative Trading Organizations” and the second-mover companies. Then, we recall the theoretical emergence factors for each type of organization (nonprofit, co-operative and for-profit) and apply these emergence factors to the context of Fair Trade. This analysis allows us to capture the specificities of each type of operator with regard to Fair Trade and, thus, to have a better understanding of the dynamics in the sector. Such dynamics includes competition, but also conflict and partnership. Our analysis includes elements on ethical imitation, consumers’ behaviors, effects on welfare and the role of the government. [less ▲]

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See detailDynamics of flood-freeze cycles during the SIMBA experiment (Brussels and Liège Stations - Bellingshaussen Sea, Antarctica)
Tison, Jean Louis; Brabant, Frederic; Geilfus, Nicolas-Xavier ULg et al

Poster (2009, March)

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See detailDynamics of global scale electron and proton precipitation induced by a solar wind pressure pulse
Meurant, M.; Gérard, Jean-Claude ULg; Hubert, Benoît ULg et al

in Geophysical Research Letters (2003), 30(20),

[1] On April 28 2001, simultaneous global images of electron and proton aurora were obtained by IMAGE- FUV following a sudden increase of solar wind dynamic pressure. The local time and intensity ... [more ▼]

[1] On April 28 2001, simultaneous global images of electron and proton aurora were obtained by IMAGE- FUV following a sudden increase of solar wind dynamic pressure. The local time and intensity distribution of both types of precipitation are examined and compared. It is found that the electron and the proton precipitation both start in the post noon sector and expand concurrently, but the expansion into the nightside starts sooner for the protons than for the electrons. The characteristic rise time in the onset sector is on the order of 6 minutes. A distinct dynamics and morphology of electron and proton precipitation is observed in the nightside sector. DMSP electron measurements in the afternoon sector indicate that the shock has a significant effect on the electron spectral characteristics. It is suggested that the various Alfven frequencies generated by the shock account for the two different speeds of propagation of the disturbance. [less ▲]

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See detailDynamics of H+ fluxes in mitochondrial membrane.
Sluse, Francis ULg; Jarmuszkiewicz, W.

in Rengel, Z. (Ed.) Handbook of plan growth : pH as the master variable (2001)

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See detailDynamics of inorganic carbon in surface waters off the Galician coast
Borges, Alberto ULg; Keir, R.; Larsen, S. E. et al

Conference (2000)

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See detailDynamics of livestock production systems during the economic transformation period in Northern Vietnam : case study in Cam Giang District, Hai Duong Province
Han Quang, Hanh ULg; Vu Dinh, Ton; Lebailly, Philippe ULg

in Koonawootrittriron, S.; Suwanasopee, T.; Jattawa, D. (Eds.) et al The 15th AAAP Animal Science Congress "Improving Smallholder and Industrial Livestock Production for Enhancing Food Security, Environment and Human Welfare" : Proceedings, Vol. II. Abstracts (2012)

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See detailThe dynamics of lysozyme from bacteriophage lambda in solution probed by NMR and MD simulations.
Smith, Lorna J.; Bowen, Alice M.; Di Paolo, Alexandre et al

in Chembiochem : a European journal of chemical biology (2013), 14(14), 1780-8

(15) N NMR relaxation studies, analyses of NMR data to include chemical shifts, residual dipolar couplings (RDC), NOEs and H(N) -H(alpha) coupling constants, and molecular dynamics (MD) simulations have ... [more ▼]

(15) N NMR relaxation studies, analyses of NMR data to include chemical shifts, residual dipolar couplings (RDC), NOEs and H(N) -H(alpha) coupling constants, and molecular dynamics (MD) simulations have been used to characterise the behaviour of lysozyme from bacteriophage lambda (lambda lysozyme) in solution. The lower and upper lip regions in lambda lysozyme (residues 51-60 and 128-141, respectively) show reduced (1) H-(15) N order parameters indicating mobility on a picosecond timescale. In addition, residues in the lower and upper lips also show exchange contributions to T2 indicative of slower timescale motions. The chemical shift, RDC, coupling constant and NOE data for lambda lysozyme indicate that two fluctuating beta-strands (beta3 and beta4) are populated in the lower lip region while the N terminus of helix alpha6 (residues 136-139) forms dynamic helical turns in the upper lip region. This behaviour is confirmed by MD simulations that show hydrogen bonds, indicative of the beta-sheet and helical secondary structure in the lip regions, with populations of 40-60 %. Thus in solution lambda lysozyme adopts a conformational ensemble that will contain both the open and closed forms observed in the crystal structures of the protein. [less ▲]

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See detailDynamics of mitotic activity and expression of viral proteins gp51 and p24 of Bovine Leukemia Virus producing cells.
Roussev, Roussi; Polianova, M.; Portetelle, Daniel ULg et al

in Folia Biologica (1993), 39

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See detailDynamics of mononuclear cadmium beta-lactamase revealed by the combination of NMR and PAC spectroscopy.
Hemmingsen, L.; Damblon, Christian ULg; Antony, J. et al

in Journal of the American Chemical Society (2001), 123(42), 10329-35

The two metal sites in cadmium substituted beta-lactamase from Bacillus cereus 569/H/9 have been studied by NMR spectroscopy ((1)H, (15)N, and (113)Cd) and PAC spectroscopy ((111m)Cd). Distinct NMR ... [more ▼]

The two metal sites in cadmium substituted beta-lactamase from Bacillus cereus 569/H/9 have been studied by NMR spectroscopy ((1)H, (15)N, and (113)Cd) and PAC spectroscopy ((111m)Cd). Distinct NMR signals from the backbone amides are identified for the apoenzyme and the mononuclear and binuclear cadmium enzymes. For the binuclear cadmium enzyme, two (113)Cd NMR signals (142 and 262 ppm) and two (111m)Cd PAC nuclear quadrupole interactions are observed. Two nuclear quadrupole interactions are also observed, with approximately equal occupancy, in the PAC spectra at cadmium/enzyme ratios < 1; these are different from those derived for the binuclear cadmium enzyme, demonstrating interaction between the two metal ion binding sites. In contrast to the observation from PAC spectroscopy, only one (113)Cd NMR signal (176 ppm) is observed at cadmium/enzyme ratios < 1. The titration of the metal site imidazole (N)H proton signals as a function of cadmium ion-to-enzyme ratio shows that signals characteristic for the binuclear cadmium enzyme appear when the cadmium ion-to-enzyme ratio is between 1 and 2, whereas no signals are observed at stoichiometries less than 1. The simplest explanation consistent with all data is that, at cadmium/enzyme ratios < 1, the single Cd(II) is undergoing exchange between the two metal sites on the enzyme. This exchange must be fast on the (113)Cd NMR time scale and slow on the (111m)Cd PAC time scale and must thus occur in a time regime between 0.1 and 10 micros. [less ▲]

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See detailDynamics of organic and inorganic carbon across contiguous mangrove and seagrass systems (Gazi bay, Kenya)
Bouillon, Steven; Dehairs, Frank; Velimirov, Branko et al

in Journal of Geophysical Research. Biogeosciences (2007), 112(G02018),

We report on the water column biogeochemistry in adjacent mangrove and seagrass systems in Gazi Bay (Kenya), with a focus on assessing the sources and cycling of organic and inorganic carbon. Mangrove and ... [more ▼]

We report on the water column biogeochemistry in adjacent mangrove and seagrass systems in Gazi Bay (Kenya), with a focus on assessing the sources and cycling of organic and inorganic carbon. Mangrove and seagrass-derived material was found to be the dominant organic carbon sources in the water column, and could be distinguished on the basis of their d13C signatures and particulate organic carbon:total suspended matter (POC/TSM) ratios. Spatially, a distinct boundary existed whereby the dominance of mangrove-derived material decreased sharply close to the interface between the mangrove forest and the dense seagrass beds. The latter is consistent with the reported export of mangrove-derived material, which is efficiently trapped in the adjacent seagrass beds. There were significant net inputs of POC and dissolved organic carbon (DOC) along the Kidogoweni salinity gradient, for which the d13CPOC signatures were consistent with those of mangroves. DOC was the dominant form of organic carbon in both mangrove and seagrass beds, with DOC/POC ratios typically between 3 and 15. Dynamics of dissolved inorganic carbon in the creeks were strongly influenced by diagenetic C degradation in the intertidal mangrove areas, resulting in significant CO2 emission from the water column to the atmosphere. Although highest partial pressure of CO2 (pCO2) values and areal CO2 flux rates were observed in the mangrove creeks, and the water column above the seagrass beds was in some locations a net sink of CO2, most of the ecosystems’ emission of CO2 to the atmosphere occurred in the seagrass beds adjacent to the mangrove forest. The presence of dense seagrass beds thus had a strong effect on the aquatic biogeochemistry, and resulted in trapping and further mineralization of mangrove-derived POC, intense O2 production and CO2 uptake. The adjacent seagrass beds provide a large area with conditions favorable to exchange of CO2 with the atmosphere, thereby limiting export of mangrove-derived organic and inorganic carbon toward the coastal ocean. [less ▲]

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See detailDynamics of PCB transfer from mother to pup during lactation in UK grey seals Halichoerus grypus: differences in PCB profile between compartments of transfer and changes during the lactation period
Debier, Cathy; Pomeroy, Paddy P.; Dupont, Cédric et al

in Marine Ecology-Progress Series (2003), 247

The composition of the PCB mixture which is transferred from mother to pup in grey seals Halichoerus grypus throughout lactation was measured in the successive compartments of transfer: maternal blubber ... [more ▼]

The composition of the PCB mixture which is transferred from mother to pup in grey seals Halichoerus grypus throughout lactation was measured in the successive compartments of transfer: maternal blubber, maternal serum, milk and pup serum. Mother-pup pairs were captured regularly between birth and weaning on the Isle of May, Scotland. The PCB profiles of the different compartments of transfer consisted mainly of congeners 153, 138, 180, 187, 170 and 101, which made up 85% of the total PCB burden. Outer blubber contained higher relative concentrations (R-153) Of hepta-, octa-, and nona-chlorinated congeners (higher chlorinated congeners) than inner blubber, at both early (less than or equal to 5 d) and late (greater than or equal to 11 d) lactation. There was no change in the composition of the outer blubber layer between early and late lactation, while in the inner blubber, there was a slight increase in the R153 of higher chlorinated congeners at late lactation. In maternal serum, profiles changed towards having a higher proportion of higher chlorinated congeners as lactation progressed, but in milk, the PCB pattern stayed constant throughout lactation. Surprisingly, in pup serum profiles also changed towards higher R153 of higher chlorinated congeners at late lactation compared to early lactation, which was different to the pattern observed in milk. In all body compartments, higher proportions of higher chlorinated congeners were associated with higher concentrations of total PCBs. Maternal blubber and pup serum contained a higher R153 of higher chlorinated congeners than milk and, to a lesser extent, maternal serum. Thus biomagnification of the higher chlorinated congeners was recorded in pup serum. [less ▲]

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See detailDynamics of pCO2 and related air-ice CO2 fluxes in the Arctic coastal zone (Amundsen Gulf, Beaufort Sea)
Geilfus, Nicolas-Xavier ULg; Carnat, G.; Papakyriakou, T. et al

in Journal of Geophysical Research. Oceans (2012), 117(C00G10),

We present an Arctic seasonal survey of carbon dioxide partial pressure (pCO2) dynamics within sea ice brine and related air-ice CO2 fluxes. The survey was carried out from early spring to the beginning ... [more ▼]

We present an Arctic seasonal survey of carbon dioxide partial pressure (pCO2) dynamics within sea ice brine and related air-ice CO2 fluxes. The survey was carried out from early spring to the beginning of summer in the Arctic coastal waters of the Amundsen Gulf. High concentrations of pCO2 (up to 1834 matm) were observed in the sea ice in early April as a consequence of concentration of solutes in brines, CaCO3 precipitation and microbial respiration. CaCO3 precipitation was detected through anomalies in total alkalinity (TA) and dissolved inorganic carbon (DIC). This precipitation seems to have occurred in highly saline brine in the upper part of the ice cover and in bulk ice. As summer draws near, the ice temperature increases and brine pCO2 shifts from a large supersaturation (1834 matm) to a marked undersaturation (down to almost 0 matm). This decrease was ascribed to brine dilution by ice meltwater, dissolution of CaCO3 and photosynthesis during the sympagic algal bloom. The magnitude of the CO2 fluxes was controlled by ice temperature (through its control on brine volume and brine channels connectivity) and the concentration gradient between brine and the atmosphere. However, the state of the ice-interface clearly affects air-ice CO2 fluxes. [less ▲]

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See detailDynamics of pentaquarks in constituent quark models: Recent developments
Stancu, Floarea ULg

in AIP Conference Proceedings (2005), 775

Some recent developments in the study of light and heavy pentaquarks are reviewed, mainly within constituent quark models. Emphasis is made on results obtained in the flavor-spin model where a nearly ... [more ▼]

Some recent developments in the study of light and heavy pentaquarks are reviewed, mainly within constituent quark models. Emphasis is made on results obtained in the flavor-spin model where a nearly ideal octet-antidecuplet mixing is obtained. The charmed antisextet is reviewed in the context of an SU(4) classification. [less ▲]

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See detailDynamics of poly((dimethylamino)alkyl methacrylate-block-sodium metha-crylate) micelles. Influence of hydrophobicity and molecular architecture on the exchange rate of copolymer molecules
Creutz, Serge; Van Stam, Jan; De Schrijver, Frans C et al

in Macromolecules (1998), 31(3), 681-689

The dynamic stability of the micellar aggregates formed by amphiphilic block copolymers, i.e., poly((dimethylamino)alkyl methacrylate-b-sodium methacrylate), has been investigated by steady-state ... [more ▼]

The dynamic stability of the micellar aggregates formed by amphiphilic block copolymers, i.e., poly((dimethylamino)alkyl methacrylate-b-sodium methacrylate), has been investigated by steady-state fluorescence spectroscopy and size exclusion chromatography. The dynamics of exchange of block copolymer molecules between the micelles, formed in aqueous solution, depend on a manifold of factors, e.g., alkyl substituent in the hydrophobic block, the relation between the hydrophobic and hydrophilic blocks, and the architecture of the block copolymer. All copolymers investigated show a slow unimer exchange with an exchange rate constant on the order of 10-3 s-1, with a difference of a factor of 20 between the fastest and the slowest exchange. It is possible to tune the exchange rate in a controlled way; for instance, an extension or branching of the alkyl chain slows down the exchange rate. The same effect is observed when the hydrophobic/hydrophilic balance of these copolymers is increased or when either the hydrophilic or the hydrophobic moiety of diblocks is divided into two external blocks, leading to a triblock copolymer. [less ▲]

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