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See detailThe DynaMICCS perspective. A mission for a complete and continuous view of the Sun dedicated to magnetism, space weather and space climate
Turck-Chièze, S.; Lamy, P.; Carr, C. et al

in Experimental Astronomy (2009), 23

The DynaMICCS mission is designed to probe and understand the dynamics of crucial regions of the Sun that determine solar variability, including the previously unexplored inner core, the radiative ... [more ▼]

The DynaMICCS mission is designed to probe and understand the dynamics of crucial regions of the Sun that determine solar variability, including the previously unexplored inner core, the radiative/convective zone interface layers, the photosphere/chromosphere layers and the low corona. The mission delivers data and knowledge that no other known mission provides for understanding space weather and space climate and for advancing stellar physics (internal dynamics) and fundamental physics (neutrino properties, atomic physics, gravitational moments...). The science objectives are achieved using Doppler and magnetic measurements of the solar surface, helioseismic and coronographic measurements, solar irradiance at different wavelengths and in-situ measurements of plasma/energetic particles/magnetic fields. The DynaMICCS payload uses an original concept studied by Thalès Alenia Space in the framework of the CNES call for formation flying missions: an external occultation of the solar light is obtained by putting an occulter spacecraft 150 m (or more) in front of a second spacecraft. The occulter spacecraft, a LEO platform of the mini sat class, e.g. PROTEUS, type carries the helioseismic and irradiance instruments and the formation flying technologies. The latter spacecraft of the same type carries a visible and infrared coronagraph for a unique observation of the solar corona and instrumentation for the study of the solar wind and imagers. This mission must guarantee long (one 11-year solar cycle) and continuous observations (duty cycle > 94%) of signals that can be very weak (the gravity mode detection supposes the measurement of velocity smaller than 1 mm/s). This assumes no interruption in observation and very stable thermal conditions. The preferred orbit therefore is the L1 orbit, which fits these requirements very well and is also an attractive environment for the spacecraft due to its low radiation and low perturbation (solar pressure) environment. This mission is secured by instrumental R and D activities during the present and coming years. Some prototypes of different instruments are already built (GOLFNG, SDM) and the performances will be checked before launch on the ground or in space through planned missions of CNES and PROBA ESA missions (PICARD, LYRA, maybe ASPIICS). [less ▲]

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See detailDynamics and constraints of livestock production systems in Cam Giang district, Hai Duong Province, North Vietnam
Han Quang, Hanh ULg; Vu Dinh, Ton; Lebailly, Philippe ULg

in Livestock Research for Rural Development (2013), 25(9),

In Northern Vietnam, the livestock production sector has been strongly encouraged to develop by the government for many years as an important livelihood strategy to alleviate household poverty. Over the ... [more ▼]

In Northern Vietnam, the livestock production sector has been strongly encouraged to develop by the government for many years as an important livelihood strategy to alleviate household poverty. Over the last few decades, it has been developed quickly, but remained unsustainable. This study aims to identify the dynamics of livestock production systems during the economic transformation period and their current constraints as the basic for setting up sustainable development policies. A survey, which is based on participatory and retrospective approaches, was conducted at 38 households in two communes of Hai Duong province in 2010. The results indicated a significant evolution of livestock production systems from a traditional small-scale production system into a specialized intensive one due to the land law and the rice land conversion program in 1990s and the industrialization and urbanization process in 2000s. The intensification of livestock production system, which is accompanied by the increasing dependence on imported inputs and the limited knowledge and skills in adequate techniques and disease management, poses a huge difficulty to producers in developing their livestock production systems. Therefore, the priority of development policies should be given to the promotion of the local resource utilisation as feed for animals and to the improvement of farmers’ ability to manage their production through not only government supports but also participation of social organisations and farmers. [less ▲]

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See detailDynamics and statistics of wave-particle interactions in a confined geometry
Gilet, Tristan ULg

in Physical Review. E : Statistical, Nonlinear, and Soft Matter Physics (2014), 90

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See detailDynamics and three-dimensional localization of ribosomal RNA within the nucleolus.
Thiry, Marc ULg; Cheutin, T.; O'Donohue, M. F. et al

in RNA (New York, N.Y.) (2000), 6(12), 1750-61

Although rRNA synthesis, maturation, and assembly into preribosomal particles occur within the nucleolus, the route taken by pre-rRNAs from their synthetic sites toward the cytoplasm remains largely ... [more ▼]

Although rRNA synthesis, maturation, and assembly into preribosomal particles occur within the nucleolus, the route taken by pre-rRNAs from their synthetic sites toward the cytoplasm remains largely unexplored. Here, we employed a nondestructive method for the incorporation of BrUTP into the RNA of living cells. By using pulse-chase experiments, three-dimensional image reconstructions of confocal optical sections, and electron microscopy analysis of ultrathin sections, we were able to describe topological and spatial dynamics of rRNAs within the nucleolus. We identified the precise location and the volumic organization of four typical subdomains, in which rRNAs are successively moving towards the nucleolar periphery during their synthesis and processing steps. The incorporation of BrUTP takes place simultaneously within several tiny spheres, centered on the fibrillar centers. Then, the structures containing the newly synthesized RNAs enlarge and appear as compact ringlets disposed around the fibrillar centers. Later, they form hollow spheres surrounding the latter components and begin to fuse together. Finally, these structures widen and form large rings reaching the limits of the nucleoli. These results clearly show that the transport of pre-rRNAs within the nucleolus does not occur randomly, but appears as a radial flow starting from the fibrillar centers that form concentric rings, which finally fuse together as they progress toward the nucleolar periphery. [less ▲]

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See detailDynamics Characterization of Fully Hydrated Bacterial Cell Walls by Solid-State NMR: Evidence for Cooperative Binding of Metal Ions
Kern, Thomas; Giffard, Mathilde; Hediger, Sabine et al

in Journal of the American Chemical Society (2010), 132

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See detailDynamics in mangroves assessed by high-resolution and multi-temporal satellite data: a case study in Zhanjiang Mangrove National Nature Reserve (ZMNNR), P. R. China
Leempoel, K; Satyaranayana, B; Bourgeois, C et al

in Biogeosciences Discussions (2013), 10

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See detailDynamics in miscible blends of polystyrene and poly(vinyl methyl ether)
Pathak, J. A.; Colby, R. H.; Floudas, G. et al

in Macromolecules (1999), 32(8), 2553-2561

We report results on the linear viscoelasticity (oscillatory shear in the temperature range Tg (glass-transition temperature) ≤ T ≤ Tg + 90 K) of miscible blends of polystyrene (PS) and poly(vinyl methyl ... [more ▼]

We report results on the linear viscoelasticity (oscillatory shear in the temperature range Tg (glass-transition temperature) ≤ T ≤ Tg + 90 K) of miscible blends of polystyrene (PS) and poly(vinyl methyl ether) (PVME) and segmental relaxations, measured by dielectric spectroscopy. The Flory−Huggins interaction parameter of this blend is weakly negative, and the glass transitions of the pure components are quite disparate (ΔTg = 125 K). PS/PVME blends have been found to be consistently thermorheologically complex at both the segmental and terminal levels: the empirical time−temperature superposition (tTS) principle applies to neither their oscillatory shear response nor their dielectric response. Using the tube model, we quantitatively compare dielectric and mechanical results. At low temperatures, the effective time scale for motion of a Kuhn segment (the shortest Rouse mode) is near the long-time end of the distribution of segmental relaxation times of PVME, in both the pure and blended states. The slowest relaxing segments thus control the longer-time relaxation processes of the chains. Miscible blends with weak interactions and large ΔTg have concentration fluctuations that broaden the distribution of segmental relaxation times. This distribution narrows as the temperature is raised in the blend, leading to the failure of tTS for terminal dynamics. [less ▲]

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See detailDynamics of a bouncing dimer
Dorbolo, Stéphane ULg; Volfson, D.; Tsimring, L. et al

in Physical Review Letters (2005), 95(4),

We investigate the dynamics of a dimer bouncing on a vertically oscillated plate. The dimer, composed of two spheres rigidly connected by a light rod, exhibits several modes depending on initial and ... [more ▼]

We investigate the dynamics of a dimer bouncing on a vertically oscillated plate. The dimer, composed of two spheres rigidly connected by a light rod, exhibits several modes depending on initial and driving conditions. The first excited mode has a novel horizontal drift in which one end of the dimer stays on the plate during most of the cycle, while the other end bounces in phase with the plate. The speed and direction of the drift depend on the aspect ratio of the dimer. We employ event-driven simulations based on a detailed treatment of frictional interactions between the dimer and the plate in order to elucidate the nature of the transport mechanism in the drift mode. [less ▲]

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See detailDynamics of a bouncing droplet onto a vertically vibrated interface
Gilet, Tristan ULg; Terwagne, Denis ULg; Vandewalle, Nicolas ULg et al

in Physical Review Letters (2008), 100(16),

Low viscosity (< 100 cSt) silicon oil droplets are placed on a high viscosity (1000 cSt) oil bath that vibrates vertically. The viscosity difference ensures that the droplet is more deformed than the bath ... [more ▼]

Low viscosity (< 100 cSt) silicon oil droplets are placed on a high viscosity (1000 cSt) oil bath that vibrates vertically. The viscosity difference ensures that the droplet is more deformed than the bath interface. Droplets bounce periodically on the bath when the acceleration of its sinusoidal motion is larger than a threshold value. The threshold is minimum for a particular frequency of excitation: droplet and bath motions are in resonance. The bouncing droplet has been modeled by considering the deformation of the droplet and the lubrication force exerted by the air layer between the droplet and the bath. Threshold values are predicted and found to be in good agreement with our measurements. [less ▲]

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See detailDynamics of a grain-filled ball on a vibrating plate
Pacheco-Vazquez, felipe; Ludewig, François ULg; Dorbolo, Stéphane ULg

in Physical Review Letters (2014), 113

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See detailDynamics of a Strongly Nonlinear Spacecraft Structure Part I: Experimental Identification
Noël, Jean-Philippe ULg; Renson, Ludovic ULg; Kerschen, Gaëtan ULg

in Proceedings of the 13th European Conference on Spacecraft Structures, Materials and Environmental Testing (2014, April)

The present paper addresses the identification of a real-life spacecraft structure possessing a strongly nonlinear component with multiple mechanical stops. The complete identification procedure, from ... [more ▼]

The present paper addresses the identification of a real-life spacecraft structure possessing a strongly nonlinear component with multiple mechanical stops. The complete identification procedure, from nonlinearity detection and characterization to parameter estimation, is carried out based upon experimental sine-sweep data collected during a classical spacecraft qualification campaign. [less ▲]

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See detailDynamics of a Strongly Nonlinear Spacecraft Structure Part II: Modal Analysis
Renson, Ludovic ULg; Noël, Jean-Philippe ULg; Kerschen, Gaëtan ULg

in Proceedings of the 13th European Conference on Spacecraft Structures, Materials & Environmental Testing (2014, April)

The present paper investigates the dynamics of a real-life spacecraft structure possessing a strongly nonlinear component with multiple mechanical stops. A full-scale finite element model is built for ... [more ▼]

The present paper investigates the dynamics of a real-life spacecraft structure possessing a strongly nonlinear component with multiple mechanical stops. A full-scale finite element model is built for gaining additional insight into the nonlinear dynamics that was observed experimentally in a companion paper (Part I). To this end, advanced techniques and theoretical concepts such as numerical continuation and nonlinear normal modes are exploited. [less ▲]

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See detailDynamics of Agrarian Systems in Hai Duong Province, North Vietnam
Han Quang, Hanh ULg

Doctoral thesis (2013)

In Vietnam, the agrarian systems have evolved considerably during the socio-economic transformation period initiated in the late 1980s with the political reform (Doi Moi). In a region around the capital ... [more ▼]

In Vietnam, the agrarian systems have evolved considerably during the socio-economic transformation period initiated in the late 1980s with the political reform (Doi Moi). In a region around the capital, where the process of industrialization, urbanization, and international integration has been accelerating, a number of questions about the sustainability of agrarian systems are raising. By diagnosing and analysing the dynamics of agrarian systems from 1980 to 2010, this study aims to provide decision-makers with some sectorial and territorial policy options authorizing the sustainable development of agriculture and rural society in the new socio-economic context. Combining the historical, adaptive, and systematic approaches, this study shows that farmers in Hai Duong province adapted effectively to the socio-economic and institutional changes, notably by transforming part of the rice land areas into other agricultural land use purposes such as fish ponds, animal buildings, vegetable fields and fruit orchards. These rapid changes, however, do not go in the direction of improving the sustainability of agrarian systems. Farm holders are now facing with many technical and economic contradictions whereas land issues are not only related to the agricultural purposes. Competition functions in land use, fragmentation of plots, the imperfection of the land market and rising property values are all emerging. The prospects for sustainability of agrarian systems are analysed under different scenarios which highlight the complexity of policy options. The recommendations are made not only for the agricultural sector in general, but also for different agrarian systems in specific regions. [less ▲]

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See detailDynamics of black-grass populations depending on the sowing time of winter wheat
Vandersteen, Joëlle; Jaunard, Delphine ULg; Mahy, Grégory ULg et al

in Communications in Agricultural and Applied Biological Sciences (2011, May 24), 76(3), 485-490

Currently, economic, agronomic and environmental concerns, lead to reduce use of herbicides. This reduction can be help by cultural measures like delay of the sowing date. Four sowing dates of winter ... [more ▼]

Currently, economic, agronomic and environmental concerns, lead to reduce use of herbicides. This reduction can be help by cultural measures like delay of the sowing date. Four sowing dates of winter wheat from 15th of October to 26th of November were tested. Dynamic of black-grass populations and their reproduction rate were assessed as well as dynamic of winter wheat for each date. Delay of sowing could significantly reduce reproduction rate of blac-grass. It was shwn that the emergence rate (pl/m²), but also number of ears per plant and number of seeds per ear of black-grass decreased significantly with the sowing date. This reproduction of seeds productioin already is from sixty per cent of a delay of two weeks sowing. [less ▲]

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See detailThe Dynamics of Complex Formation between Amylose Brushes on Gold and Fatty Acids by QCM‐D
Cao, Zheng; Tsoufis, Theodoros; Svaldo Lanero, Tiziana ULg et al

in Biomacromolecules (2013), 14

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See detailDynamics of complex molecular systems with numerical kinetic energy operators in generalized coordinates
Lauvergnat, David; Baloitcha, Ezinvi; Dive, Georges ULg et al

in Chemical Physics (2006), 326(2-3), 500-508

Dynamics of complex molecular systems in generalized coordinates (q,p) using numerical kinetic energy operators is investigated. The kinematical tools necessary for quantum, classical or semiclassical ... [more ▼]

Dynamics of complex molecular systems in generalized coordinates (q,p) using numerical kinetic energy operators is investigated. The kinematical tools necessary for quantum, classical or semiclassical dynamics with or without constraints mainly come from the covariant and contravariant components of the metric tensor and their derivatives up to the second ones. These quantities are computed numerically but without any other approximation than the numerical precision by the code TNUM. This code generates kinetic energy operators in the internal coordinates of the Z-matrix describing the molecular frame geometry in the ab initio quantum chemistry step or in symmetry adapted coordinates [D. Lauvergnat, A. Nauts, J. Chem. Phys. 116 (2002) 8560]. Various reduced dimensionality models can be used in the upgraded code. The interface with an ab initio code is calibrated on a 22-atom system for which a two-dimensional quantum treatment with a constrained Hamiltonian has been carried out previously. The test application concerns the spreading properties of a wave packet in an unstable flat region around a valley ridge inflexion point between two transition states in the Endo-dimerization of cyclopentadiene. We perform here on-the-fly classical or semiclassical dynamics in full or reduced dimensionality. (c) 2006 Elsevier B.V. All rights reserved. [less ▲]

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See detailDynamics of copepod faecal pellets in relation to a Phaeocystis dominated phytoplankton bloom: characteristics, production and flux
Frangoulis, Costa; Belkhiria, Sami; Goffart, Anne ULg et al

in Journal of Plankton Research (2001), 23(1), 75-88

Copepod faecal pellet characteristics and production were measured in spring 1995, 1996 and 1997 in the North Sea Southern Bight in order to define changes due to the development of the phytoplankton ... [more ▼]

Copepod faecal pellet characteristics and production were measured in spring 1995, 1996 and 1997 in the North Sea Southern Bight in order to define changes due to the development of the phytoplankton bloom. Changes were related to the succession from diatoms to a Phaeocystis sp. bloom. Mean monthly pellet production decreased during the Phaeocystis bloom development to 0.27 pellets ind. –1 h –1, approximately 80% lower than before and after the bloom. Although phytoplanktonic pigments showed significant differences between inshore and offshore stations, there was no such significant difference for faecal pellet production. Faecal pellet sinking-rate decreased from 100 to 70 m day –1 during the transition from a diatom- to a Phaeocystis-dominated bloom. This was due to a decrease in pellet density and/or a decrease of the pellet volume. These results supported the idea of lower feeding of copepods under Phaeocystis bloom conditions. As mean seasonal density of copepod faecal pellets was higher (1.37 g cm –3) than in other seas, accidental ingestion of sedimentary material as the cause of this high density is discussed. [less ▲]

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