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See detailDecoding the folding of Burkholderia glumae lipase: folding intermediates en route to kinetic stability
Pauwels, Kris; Sanchez del Pino, Manuel M.; Feller, Georges ULg et al

in PLoS ONE (2012), 7(5), 36999

Detailed reference viewed: 30 (4 ULg)
See detailDecoherence of an Entangled Atomic Pair
Agarwal, G. S.; Bastin, Thierry ULg; von Zanthier, J.

Conference (2006)

Detailed reference viewed: 9 (1 ULg)
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See detailDecoherence, entanglement and irreversibility in quantum dynamical systems with few degrees of freedom
Jacquod, Ph; Petitjean, Cyril ULg

in Advances in Physics (2009), 58(2), 67-196

In this review we summarize and amplify recent investigations of coupled quantum dynamical systems with few degrees of freedom in the short-wavelength, semiclassical limit. Focusing on the correspondence ... [more ▼]

In this review we summarize and amplify recent investigations of coupled quantum dynamical systems with few degrees of freedom in the short-wavelength, semiclassical limit. Focusing on the correspondence between quantum and classical physics, we mathematically formulate and attempt to answer three fundamental questions. (i) How can one drive a small dynamical quantum system to behave classically? (ii) What determines the rate at which two single-particle quantum-mechanical subsystems become entangled when they interact? (iii) How does irreversibility occur in quantum systems with few degrees of freedom? These three questions are posed in the context of the quantum-classical correspondence for dynamical systems with few degrees of freedom, and we accordingly rely on two short-wavelength approximations to quantum mechanics to answer them: the trajectory-based semiclassical approach on the one hand, and random matrix theory on the other hand. We construct novel investigative procedures towards decoherence and the emergence of classicality out of quantumness in dynamical systems coupled to external degrees of freedom. In particular, we show how dynamical properties of chaotic classical systems, such as local exponential instability in phase space, also affects their quantum counterparts. For instance, it is often the case that the fidelity with which a quantum state is reconstructed after an imperfect time-reversal operation decays with the Lyapunov exponent of the corresponding classical dynamics. For related reasons, but perhaps more surprisingly, the rate at which two interacting quantum subsystems become entangled can also be governed by the subsystem's Lyapunov exponents. Our method allows us to differentiate quantum coherent effects (those related to phase interferences) from classical ones (those related to the necessarily extended envelope of quantal wavefunctions) at each stage in our investigations. This makes it clear that all occurrences of Lyapunov exponents we witness have a classical origin, although they require rather strong decoherence effects to be observed. We extensively rely on numerical experiments to illustrate our findings and briefly comment on possible extensions to more complex problems involving environments with many interacting dynamical systems, going beyond the uncoupled harmonic oscillators model of Caldeira and Leggett. [less ▲]

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See detailDecoherence-enhanced measurements
Braun, Daniel; Martin, John ULg

Conference (2009, May)

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See detailDecommissioned dates: chemical composition and fermentation substrate for the production of extracellular catalase by an Aspergillus phoenicis mutant
Kacem-Chaouche, N.; Dehimat, L.; Meraihi, Z. et al

in Agriculture and Biology Journal of North America (2013)

The recovery of dates downgraded as a fermentation medium for the production of extracellular catalase by Aspergillus phoenicis K30 was studied. Analysis of the chemical composition of pulp and kernel ... [more ▼]

The recovery of dates downgraded as a fermentation medium for the production of extracellular catalase by Aspergillus phoenicis K30 was studied. Analysis of the chemical composition of pulp and kernel flour of dates showed that the pulp had a considerably greater carbohydrate content compared to the kernel (84 vs 2.93% respectively). However, the kernel flour was richer in nitrogen (0.68% vs 0.34), mineral elements (3.63 vs 1.28%) and in essential fatty acids C18: 2 vs C18: 3 than the pulp flour. The soluble extract of the date flour showed that sugars solubilised at 90% consisted of sucrose, fructose and glucose. Therefore, this extract, being an important source of carbon and energy, was used in the current study as a fermentation medium (after supplementation with 20% of corn steep) for the production of extracellular catalase by A. Phoenicis K30. During the course of this fermentation, the biomass was estimated at 18.6 g / L after 72 h of culture, while the maximum concentration of extracellular catalase (47.5 U / ml) was reached at 96 h of fermentation. The mycelium obtained in pellet form is suitable for industrial exploitation of this process. [less ▲]

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See detailDécompensation cardiaque, fonction rénale et anti-inflammatoires non stéroïdiens
Krzesinski, Jean-Marie ULg; Piront, Patricia ULg

in Revue Médicale de Liège (2002), 57(9), 582-586

Thanks to a case report of heart failure in an old people with a cardiovascular history treated by the new coxib-inhibitors, we would like to remember and insist to the risk of renal and cardiac ... [more ▼]

Thanks to a case report of heart failure in an old people with a cardiovascular history treated by the new coxib-inhibitors, we would like to remember and insist to the risk of renal and cardiac complications which appear to be the same as those with the non specific antiinflammatory drugs. Old age, diuretic or converting enzyme inhibitor treatment, heart failure, liver insufficiency, nephrotic syndrome are risk factors for acute renal failure and cardiac failure during such treatment. [less ▲]

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See detailDecomposing efficiency into its managerial and its regulatory components: The case of European railways
Gathon, Henry-Jean ULg; Pestieau, Pierre ULg

in European Journal of Operational Research (1995), 80

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See detailDécomposition d'un cube en quatre cubes
Catalan, Eugène ULg

in Nouvelle Correspondance Mathématique (1878), 4

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See detailDécomposition d'un cube en quatre cubes (suite)
Catalan, Eugène ULg

in Nouvelle Correspondance Mathématique (1878), 4

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See detailLa "décomposition de l'UEO (1999-2003) : variables institutionnelles et militaires
Dumoulin, André ULg

Master's dissertation (2003)

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See detailDecomposition of metabolic brain clusters in the frontal variant of frontotemporal dementia
Salmon, Eric ULg; Kerrouche, Nacer; Herholz, Karl et al

in NeuroImage (2006), 30(3), 871-878

Previous studies that measured brain activity in frontotemporal dementia (FTD) used univariate analyses, examining each region of interest separately. We explored in a multicenter European research ... [more ▼]

Previous studies that measured brain activity in frontotemporal dementia (FTD) used univariate analyses, examining each region of interest separately. We explored in a multicenter European research program the principal brain clusters characterized by a common variability in cerebral metabolism in FTD. Seventy patients with frontal variant (fv) FTD were selected according to international clinical recommendations; principal component analysis (PCA) was performed on FDG-PET metabolic images, looking for covariance clusters in this large population. A first metabolic cluster included most of the lateral and medial prefrontal cortex, bilaterally; PC1 scores correlated with performances on memory and executive neuropsychological tasks. Moreover, FDG-PET images in fv-FTD were further characterized by a metabolic covariance in two clusters comprising the subcallosal medial frontal region, the temporal pole, medial temporal structures and the striatum, separately in the left and in the right hemisphere. The study provides original data-driven arguments for metabolic involvement of separate brain clusters in the rostral limbic system, corresponding to pathological poles differentially affected in each FTD patient. [less ▲]

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See detailDecomposition of symmetric tensor fields in the presence of a flat contact projective structure
Frégier, Yaël; Mathonet, Pierre ULg; Poncin, Norbert

in Journal of Nonlinear Mathematical Physics (2008), 15(2), 252-269

Let M be an odd-dimensional Euclidean space endowed with a contact 1-form \alpha. We investigate the space of symmetric contravariant tensor fields over M as a module over the Lie algebra of contact ... [more ▼]

Let M be an odd-dimensional Euclidean space endowed with a contact 1-form \alpha. We investigate the space of symmetric contravariant tensor fields over M as a module over the Lie algebra of contact vector fields, i.e. over the Lie subalgebra made up of those vector fields that preserve the contact structure defined by \alpha. If we consider symmetric tensor fields with coefficients in tensor densities (also called symbols), the vertical cotangent lift of the contact form \alpha defines a contact invariant operator. We also extend the classical contact Hamiltonian to the space of symbols. This generalized Hamiltonian operator on the space of symbols is invariant with respect to the action of the projective contact algebra sp(2n+2) the algebra of vector fields which preserve both the contact structure and the projective structure of the Euclidean space. These two operators lead to a decomposition of the space of symbols, except for some critical density weights, which generalizes a splitting proposed by V. Ovsienko. [less ▲]

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See detailDécomposition photocatalytique de polluants et de micro-organismes dans l'eau
Heinrichs, Benoît ULg; Pirard, Jean-Paul ULg; Lambert, Stéphanie ULg et al

E-print/Working paper (2008)

Dans le cadre de la réutilisation des eaux usées et de l’accès limité à l’eau potable dans certaines régions du globe, de nouvelles techniques de désinfection nécessitant de faibles consommations ... [more ▼]

Dans le cadre de la réutilisation des eaux usées et de l’accès limité à l’eau potable dans certaines régions du globe, de nouvelles techniques de désinfection nécessitant de faibles consommations d’énergie sont étudiées. Cette eau n’est pas toujours potable et contient des polluants qui induisent des mutations génétiques pouvant conduire au développement de cancers ou encore des micro-organismes pathogènes causant des maladies graves. Depuis la découverte des propriétés de photodégradation oxydante du dioxyde de titane (TiO2), la photocatalyse hétérogène est utilisée pour l’élimination des polluants environnementaux et des micro-organismes. [less ▲]

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See detailDécomposition spectrale stochastique pour une formulation intégrale du problème de diffraction d'onde
Gaignaire, R.; Geuzaine, Christophe ULg

in Proceedings of 6ème Conférence Européenne sur les Méthodes Numériques en Electromagnétisme (NUMELEC2008) (2008)

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See detailDecomposition, Localization and Time-Averaging Approaches in Large-Scale Power System Dynamic Simulation
Fabozzi, Davide ULg

Doctoral thesis (2012)

Present-day interconnected electric power systems are the largest machines in the world. Guaranteeing a stable supply of electric power is vital for modern societies: power systems must be able to ... [more ▼]

Present-day interconnected electric power systems are the largest machines in the world. Guaranteeing a stable supply of electric power is vital for modern societies: power systems must be able to withstand plausible disturbances. A certain number of simulations of the post-disturbance behavior are routinely executed by some transmission system operators to assess that the system is operated in a secure way. Usually this assessment has to be performed within a predefined time frame, using the available computing resources. Improving the simulation speed allows the operators to perform a wider assessment, thus making better use of the available computational power. A large part of this research took place in the context of the PEGASE project, supported by European Commission (Seventh Framework Programme) and has resulted in some novel algorithms for faster dynamic simulations, one of the PEGASE project main goals. First, this thesis revisits the Newton method used to solve the differential-algebraic model. Then, three original algorithmic improvements are presented, namely (i) decomposition, (ii) localization and (iii) time-averaging of the system response. Finally, the combination of these approaches is shown to provide a fast and reliable tool for dynamic security assessment. All the presented techniques have been thoroughly tested on an academic system, a large real-life system and a realistic system of unprecedented size, representative of the whole continental European synchronous grid. [less ▲]

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See detailDeconsecrating a doctrinal monument: Raymond M. Lemaire and the revisions of the Venice Charter
Houbart, Claudine ULg

in Change Over Time (2014), (fall), 218-243

Considering himself as the “main author” of the charter, Raymond M. Lemaire has been one of the first, together with Piero Gazzola, to plead for a revision of the document. As early as 1971, the two men ... [more ▼]

Considering himself as the “main author” of the charter, Raymond M. Lemaire has been one of the first, together with Piero Gazzola, to plead for a revision of the document. As early as 1971, the two men, respectively first Secretary General and President of ICOMOS, tended to launch a debate in favour of a better consideration of the social value of heritage, and the development of specific principles for historical cities conservation, to be included in the Venice charter. Lemaire’s recent experience in that field had indeed convinced him that, contrary to the assertion of article 14, “a literal application of principles valid for monuments, considered as such, is not always possible, nor desirable, for the ensembles”. The adoption of the Amsterdam declaration didn’t put an end to his efforts. Despite his unsuccessful attempt to get a revised version approved by the ICOMOS General assembly in Moscow (1978), R.M.Lemaire always remained critical towards the charter and the application of its principles in the field, underlining, in the eighties, its shortcomings in terms of cultural diversity and, in one of his last texts, in 1996, the negative effect of article 9, leading to the idea that “the mere essence of a conservation operation is a modernist intervention on the edifice or neighbourhood”. Beyond its interest for conservation history, the awareness of Lemaire’s early critical position towards the Venice Charter should inspire the current debates and help us overcome our reluctance to challenge the sacred principles of what we consider a doctrinal monument. [less ▲]

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See detailDeconstructing folds in the depth and thickness domains: examples of the active Yakeng anticline, XinJiang China
Suppe, J; Hubert, Aurelia ULg; Wang, Xin

in Geological Society of America Abstract with Programs (2002, October)

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See detailDECONSTRUCTING LANDSCAPE IN THE MIND OF PEOPLE: AN EXPLORATION OF EVERYDAY AND WIND ENERGY LANDSCAPES
Vanderheyden, Vincent ULg

Doctoral thesis (2016)

In the 19th century, geography was defining itself as the science of landscape, led by German and French schools. Other disciplines were also interested in landscape, each one with its own definition(s ... [more ▼]

In the 19th century, geography was defining itself as the science of landscape, led by German and French schools. Other disciplines were also interested in landscape, each one with its own definition(s). In public policy, landscape has remained, for a long time, a heritage object to be protected (e.g. cultural landscapes of UNESCO). In 2000, the European Landscape Convention, which aims to safeguard the European landscape diversity, proposed a common definition. This includes the idea of areas perceived by people. One of the recommendations of the Convention is the call to focus on other landscapes that only heritage landscapes, such as everyday landscapes and degraded landscapes. The convention also calls for better management and planning practices towards landscape changes. Today, landscape is often invoked as arbitrator in territorial disputes. This is the case in discussions for the installation of wind farms. Newcomers and farmers ‘visions on landscape are often opposed: idyllic landscape for living and recreation for the firsts, working environment for the seconds. Despite the European Landscape Convention, many grey areas remain about how to achieve its goals. Long before it, leading researchers called for a better interest in everyday landscapes. Yet they remain the poor relation in landscape research, to the benefit of natural, wild landscapes. Many uncertainties also remain on how non-specialists perceive their ordinary landscapes and how they have appropriated the landscape concept. The research helps to fill this double gap, deconstructing the concept through the lens of ordinary landscape. With several research questions, I plan to explore what is the landscape in people’s mind, how they conceptualize it, how they think it and how they question their own views on landscape. I will show how these conceptualizations and thoughts are shaped by the living environment, which often provides the tools necessary to the apprehension of the landscape. I will analyse how new elements such as wind farm can disrupt these patterns. The first part of the research is dedicated to the overall perception of their ordinary landscapes by Belgians, especially facing the issue of wind energy. Using a photo-questionnaire survey, we surveyed a representative sample of the Belgian population (n = 1542). Based on this investigation a model was developed. It highlights the positive influence of forest cover and the lack of anthropogenic elements, but also the negative influence of its urbanization and too flat relief on landscape attractiveness. The influence of wind turbines has to be qualified according to the landscape in which they are implanted. In landscapes strongly marked by the human footprint, they seem perceived as increasing the landscape attractiveness. In unspoilt landscapes, they seem rather to contribute to their degradation. These global findings are nuanced in further research. Deeper analysis shows that Flemish people have a more positive view of the landscape than Walloons. I hypothesize a decisive influence of the local context. Indeed, Flemish landscapes are generally more urbanized and marked by man than most of the Walloon landscapes. The building of wind farms seems to change or even reverse the situation. The analysis also shows significant influences related to educational level and gender. Anthropogenic landscapes are less disregarded by low educated people. Women seem to attach importance to stewardship and landscape maintenance. In contrast, although suspected, age influence has not been formally demonstrated. The second part of this dissertation, the cornerstone of this doctoral research, aims at deconstructing the landscape concept in the mind of people. In this part, wind farms are no longer considered as a case study, but as a leitmotif. I deeper surveyed smaller groups (n = 54) in three areas of Wallonia (Walloon Picardy, between the Sambre and Meuse rivers, and Ardennes) with qualitative techniques. This survey was conducted five years after the first. The analysis of the vocabulary used by the regional sub-groups shows that people are not equipped the same way for analysing landscapes. The experience of living environment seems to be crucial in providing analytical keys. Thus Ardennes people seem better equipped to talk about the forest, marking their landscapes, while the Picards seem more loquacious about their iconic cultivated landscapes. The research also highlighted different landscape analysis patterns. Some people ordered landscapes according to their degree of naturalness, the less spoiled landscapes being the most attractive. On the contrary, fewer attach importance to landscapes where human footprint is clearly visible. Some respondents remain in a purely aesthetic landscape analysis, while others project themselves into the landscape, imagining they are performing different actions. Depending on their interests, these actions influence the perception of one same landscape. Research shows that this overall pattern analysis is disturbed by various factors. The recognition of certain places transformed landscape analysis in an analysis of the place, with the emotional changes that this entails. The position of the participants facing wind energy projects also appears sharper. In the time between the two parts of the research, Wallonia has experienced unprecedented wind development; opinions have therefore had time to form. This was not yet totally the case during the first survey. Beyond these major disruptions, the research also shows clear influences of the ordered character of landscapes, their living character and variety of land uses. The research also highlights the influence of non-visual criteria such as noise or odours detectable in the landscape. In conclusion, the research shows that respondents often show a sense of landscape, weaker than sense of place and stronger than aesthetic. [less ▲]

Detailed reference viewed: 78 (20 ULg)