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See detailFerromagnetism induced by entangled charge and orbital orderings in ferroelectric titanate perovskites
Bristowe, Nicholas ULg; Varignon, Julien ULg; Fontaine, Denis et al

in Nature Communications (2015), 6

In magnetic materials, the Pauli exclusion principle typically drives anti-alignment between electron spins on neighbouring species resulting in antiferromagnetic behaviour. Ferromagnetism exhibiting ... [more ▼]

In magnetic materials, the Pauli exclusion principle typically drives anti-alignment between electron spins on neighbouring species resulting in antiferromagnetic behaviour. Ferromagnetism exhibiting spontaneous spin alignment is a fairly rare behaviour, but once materialized is often associated with itinerant electrons in metals. Here we predict and rationalize robust ferromagnetism in an insulating oxide perovskite structure based on the popular titanate series. In half-doped layered titanates, the combination of Jahn–Teller and oxygen breathing motions opens a band gap and creates an unusual charge and orbital ordering of the Ti d electrons. It is argued that this intriguingly intricate electronic network favours the elusive inter-site ferromagnetic (FM) ordering, on the basis of intra-site Hund's rules. Finally, we find that the layered oxides are also ferroelectric with a spontaneous polarization approaching that of ​BaTiO3. The concepts are general and design principles of the technologically desirable FM ferroelectric multiferroics are presented. [less ▲]

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See detailUsing XCO2 retrievals for assessing the long-term consistency of NDACC/FTIR data sets
Barthlott, S; Schneider, M; Hase, F et al

in Atmospheric Measurement Techniques (2015), 8

Within the NDACC (Network for the Detection of Atmospheric Composition Change), more than 20 FTIR (Fourier-transform infrared) spectrometers, spread worldwide, provide long-term data records of many ... [more ▼]

Within the NDACC (Network for the Detection of Atmospheric Composition Change), more than 20 FTIR (Fourier-transform infrared) spectrometers, spread worldwide, provide long-term data records of many atmospheric trace gases. We present a method that uses measured and modelled XCO2 for assessing the consistency of these NDACC data records. Our XCO2 retrieval setup is kept simple so that it can easily be adopted for any NDACC/FTIR-like measurement made since the late 1950s. By a comparison to coincident TCCON (Total Carbon Column Observing Network) measurements, we empirically demonstrate the useful quality of this suggested NDACC XCO2 product (empirically obtained scatter between TCCON and NDACC is about 4‰ for daily mean as well as monthly mean comparisons, and the bias is 25 ‰). Our XCO2 model is a simple regression model fitted to CarbonTracker results and the Mauna Loa CO2 in situ records. A comparison to TCCON data suggests an uncertainty of the model for monthly mean data of below 3 ‰. We apply the method to the NDACC/FTIR spectra that are used within the project MUSICA (multi-platform remote sensing of isotopologues for investigating the cycle of atmospheric water) and demonstrate that there is a good consistency for these globally representative set of spectra measured since 1996: the scatter between the modelled and measured XCO2 on a yearly time scale is only 3 ‰. [less ▲]

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See detailFormulations of the bed slope term in the shallow water equations: implication for energy balance
Bruwier, Martin ULg; Archambeau, Pierre ULg; Erpicum, Sébastien ULg et al

in Workshop on Advances in Numerical Modelling of Hydrodynamics (2015, March 24)

For an incompressible, isothermal, continuous and frictionless flow, the exact resolution of the equation of conservation of mechanical energy is equivalent to the exact resolution of the equation of ... [more ▼]

For an incompressible, isothermal, continuous and frictionless flow, the exact resolution of the equation of conservation of mechanical energy is equivalent to the exact resolution of the equation of momentum conservation. However, the discrete solution of the equation of momentum conservation does not verify the equation of energy conservation. This is particularly the case as a result of the presence of a non-conservative bed slope term in the equation of momentum conservation. In this research, the influence of (i) the formulation and (ii) the discretization scheme of the non-conservative bed slope term on the energy conservation is analysed in the case of a 1D horizontal and frictionless channel with a topographic step. The results for two different formulations of the bed slope term are firstly compared: the standard formulation of the bed slope source term and a divergence formulation of the bed slope term. Then, different discretization schemes of the divergence formulation of the bed slope term are analyzed to determine the one minimizing the numerical variation of energy. [less ▲]

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See detailEsquisse d’un modèle clinique à trois dimensions : Identité et schizophrénie
Englebert, Jérôme ULg

Scientific conference (2015, March 23)

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See detailEnfants, témoins de violences conjugales : plus que des dommages collatéraux !
Garcet, Serge ULg

Article for general public (2015)

L'article aborde différentes considérations autour des conséquences pour l'enfant d'un environnement parental violent.

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See detailPast changes in the vertical distribution of ozone – Part 3: Analysis and interpretation of trends
Harris, N. R. P.; Hassler, B.; Tummon, F. et al

in Atmospheric Chemistry & Physics Discussions (2015), 15(6), 8565--8608

Trends in the vertical distribution of ozone are reported and compared for a number of new and recently revised datasets. The amount of ozone-depleting compounds in the stratosphere (as measured by ... [more ▼]

Trends in the vertical distribution of ozone are reported and compared for a number of new and recently revised datasets. The amount of ozone-depleting compounds in the stratosphere (as measured by Equivalent Effective Stratospheric Chlorine – EESC) maximised in the second half of the 1990s. We therefore examine the trends in the periods before and after that peak to see if any change in trend is discernible in the ozone record. Prior to 1998, trends in the upper stratosphere (~ 45 km, 4 hPa) are found to be −5 to −10% per decade at mid-latitudes and closer to −5% per decade in the tropics. No trends are found in the mid-stratosphere (28 km, 30 hPa). Negative trends are seen in the lower stratosphere at mid-latitudes in both hemispheres and in the deep tropics. However it is hard to be categorical about the trends in the lower stratosphere for three reasons: (i) there are fewer measurements, (ii) the data quality is poorer, and (iii) the measurements in the 1990s are perturbed by aerosols from the Mt. Pinatubo eruption in 1991. These findings are similar to those reported previously even though the measurements for the two main satellite instruments (SBUV and SAGE II) and the ground-based Umkehr and ozonesonde stations have been revised. There is no sign of a continued negative trend in the upper stratosphere since 1998: instead there is a hint of an average positive trend of ~ 2% per decade in mid-latitudes and ~ 3% per decade in the tropics. The significance of these upward trends is investigated using different assumptions of the independence of the trend estimates found from different datasets. The averaged upward trends are significant if the trends derived from various datasets are assumed to be independent, but are generally not significant if the trends are not independent. This arises because many of the underlying measurement records are used in more than one merged dataset. At this point it is not possible to say which assumption is best. Including an estimate of the drift of the overall ozone observing system decreases the significance of the trends. The significance will become clearer as (i) more years are added to the observational record, (ii) further improvements are made to the historic ozone record (e.g. through algorithm development), and (iii) the data merging techniques are refined, particularly through a more rigorous treatment of uncertainties. [less ▲]

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See detailLe programme gouvernemental (2014-2019) en questions
Grandjean, Geoffrey ULg

Conference given outside the academic context (2015)

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See detailDispreferred structures through language change: the diachrony of affix ordering in Ancient Egyptian - Coptic
Grossman, Eitan; Polis, Stéphane ULg

Conference (2015, March 23)

Given a worldwide preference for suffixes over prefixes, why do some languages nonetheless have a macro-preference for prefixes? In this talk, we show that Ancient Egyptian-Coptic (Afroasiatic) shows a ... [more ▼]

Given a worldwide preference for suffixes over prefixes, why do some languages nonetheless have a macro-preference for prefixes? In this talk, we show that Ancient Egyptian-Coptic (Afroasiatic) shows a long-term diachronic macro-change from mixed suffixing-prefixing to an overwhel¬ming preference for prefixing. We argue that each of the micro-changes implicated in this macro-change are better understood in terms of regular changes at the level of individual constructions, via, e.g., grammaticalization, rather than in terms of a broad Sapirian ‘drift.’ Crucially, it is the particular constellation of structural features of the language at a particular moment in time, together with regular mechanisms of language change, that give rise to the cross-linguistically unusual ‘macro-preference’ of the language. [less ▲]

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See detailVoltaire as a playwright, an off-centered strategy?
Daubercies, Laurence ULg

Conference (2015, March 21)

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See detailDie "Preußische Wallonie im Ersten Weltkrieg" (1914-1920)
Brüll, Christoph ULg

Conference given outside the academic context (2015)

Die deutschsprachigen Belgier betrachten ihre jüngere Geschichte zumeist aus der Perspektive einer Minderheit. Die Erinnerung an den Ersten Weltkrieg vor hundert Jahren bietet Christoph Brüll den Anlass ... [more ▼]

Die deutschsprachigen Belgier betrachten ihre jüngere Geschichte zumeist aus der Perspektive einer Minderheit. Die Erinnerung an den Ersten Weltkrieg vor hundert Jahren bietet Christoph Brüll den Anlass, sich mit der damals wohl kleinsten Minderheit des deutschen Kaiserreiches zu befassen: den rund 10.000 „preußischen Wallonen“ im Kreis Malmedy. Der Vortrag fragt nach deren Identität im Kaiserreich, wo sie zu Kollateralopfern der gegen größere Minderheiten gerichteten Germanisierungspolitik wurden, woraus ein wallonischer Kulturpartikularismus an der deutsch-belgischen Grenze resultierte. Dabei wird auch die Offenheit dieser Grenze vor dem August 1914 deutlich, die durch intensive grenzüberschreitende soziale, wirtschaftliche und auch kulturelle Kontakte gekennzeichnet ist. Umso dramatischer wurde dort der Beginn des Ersten Weltkriegs empfunden. Die Haltung der Bevölkerung während dieses Kriegs ist jedoch von der Forschung bisher kaum in den Blick genommen worden. Der Prozess einer sich beschleunigenden Nationalisierung der kleinen Region und die Reaktion der Bevölkerung darauf werden anhand verschiedener Aspekte wie Militär, Kirche und Schule dargestellt. Der Vortrag geht auch auf die Erfahrung des Kriegsendes und der darauf folgenden Besatzungszeit durch britische Truppen, die im August 1919 von belgischen Soldaten abgelöst wurden, ein. Nicht zuletzt unternimmt er den Versuch, die Entwicklung der Jahre 1914-1920 nicht von ihrem Ende – d.h. aus der Sicht des Staatenwechsels von 1920 – zu betrachten, womit die Kriegs- und Nachkriegserfahrung der Bevölkerung in den Mittelpunkt der Betrachtung rückt . [less ▲]

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See detailNueva visión en las relaciones médico-paciente, de la Prevención Cuaternaria a la Actitud Cuaternaria.
Jamoulle, Marc ULg

Conference (2015, March 21)

Allocution plénière finale du congrès de Montevideo de la Wonca CIMF Description du concept de prévention quaternaire. Annonce de la parution et présentation des auteurs du numéro spécial de la revue ... [more ▼]

Allocution plénière finale du congrès de Montevideo de la Wonca CIMF Description du concept de prévention quaternaire. Annonce de la parution et présentation des auteurs du numéro spécial de la revue Brésilienne de médecin de famille et communautaire (RBMFC) qui va paraitre incessamment sur ce thème. Annonce de la création par les représentants des associations de médecine de famille de 15 pays, au sein de la branche ibéro américaine de la Wonca (Wonca CIMF), d'un groupe d'intérêt sur la prévention quaternaire [less ▲]

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See detailEntorse de cheville aigüe - Le traitement fonctionnel
Kaux, Jean-François ULg

Conference (2015, March 21)

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See detailImproving knowledge on Forest elephant’s ecophysiology (Loxodonta africana cyclotis) for better wildlife conservation
Ngama, Steeve ULg; Vermeulen, Cédric ULg; Bindelle, Jérôme ULg

Poster (2015, March 21)

Conservation of large wildlife species is currently a major issue in Africa. Protected areas dedicated for biodiversity conservation unfortunately do not suffice and conservation practices must be ... [more ▼]

Conservation of large wildlife species is currently a major issue in Africa. Protected areas dedicated for biodiversity conservation unfortunately do not suffice and conservation practices must be extended to man-used areas. But in those areas conservation actions are limited because of conflicts between human and wildlife especially due to damages on crops. The worst crop raiders known are elephants because they can destroy the yearly harvest of a field in a single visit. This threatens not only people livelihoods but also elephants themselves when angry farmers retaliate by shooting or trapping them. After decades of investigations crop raiding drivers related to elephants’ ecophysiology remain largely unknown. A pilot study was conducted between July and November 2014 in Monts de Cristal National Park (Gabon, central Africa) to have a first view on environmental drivers to crop raiding. While the presence of some fruiting trees around crop fields lead to more damages, high slopes discouraged elephants. In further experiments, the link between the nutritive value of raided plants and the animal’s physiological requirements and status will be assessed through hormones and parasites measurements; while tracking of individual elephants’ movements using DNA analyses in feces will be done. [less ▲]

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See detailNiche modeling within and between species in the genus Erythrophleum : intergating phylogenetic data and environmental niche models to explore speciation mechanisms
Gorel, Anaïs ULg

Poster (2015, March 21)

In this study we investigated the climatic niche between and within closely related tropical tree species of the Erythrophleum genus (Fabaceae, Caesalpinioideae): E. ivorense, E. suaveolens and E ... [more ▼]

In this study we investigated the climatic niche between and within closely related tropical tree species of the Erythrophleum genus (Fabaceae, Caesalpinioideae): E. ivorense, E. suaveolens and E. africanum. Two major hypotheses, the refuge theory and the ecological gradient hypothesis, have been developed to explain the current distribution of tree clades across tropical Africa. To identify the speciation mechanisms, we used a combination of geographic data and environmental factors to quantify the degree of niche conservatism (or divergence). We used two sets of distribution data for the purpose of this study. Species distribution data for the whole of tropical Africa was gathered from herbarium records. Distribution data of the two sister species E. ivorense and E. suaveolens assigned to genetic cluster were available for the lowland tropical forests of western and central Africa. Using a Species Distribution Model approach based on MaxEnt algorithm we tested for the environmental differences between species and genetic clusters within species. At species level, the climatic niche significantly differed and only slightly overlapped, suggesting a parapatric speciation along a climatic gradient. Within the two sister species, the niche of the parapatric central African genetic clusters suggests mostly a secondary contact following the recolonization from different forest refugia. [less ▲]

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See detailRessources secondaires et matériaux bio-sourcés pour une construction durable
Courard, Luc ULg

Scientific conference (2015, March 20)

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See detailRomanian Standards for Energy Performance in Buildings Translation of the Romanian Standards for Energy Performance in Buildings
Attia, Shady ULg; Ana Muresan, Adina

Report (2015)

This work is a part of the Master of Science Thesis written during the mobility organized by the Erasmus + Programme for exchange students at Universite de Liege, in Belgium (Université de Liège, Belgique ... [more ▼]

This work is a part of the Master of Science Thesis written during the mobility organized by the Erasmus + Programme for exchange students at Universite de Liege, in Belgium (Université de Liège, Belgique), which is in bilateral agreement with Technical University of Cluj-Napoca, in Romania (Universitatea Tehnica din Cluj-Napoca, România) available between 2014 – 2020. The audience of this technical report is civil engineers and specialists in building energy and it aims to inform about the content of the standards for building energy performance used in Romania. The report presents the essential information of the Romanian standards for building energy performance, such as the calculation of the global thermal insulation coefficient or the annual heating demand, along with some critical aspects regarding the efficiency of the standards and their alignment with the European requirements and regulations. The original content of the standards is found in the official language Romanian and is published in the special law publication from Romania named Monitorul Oficial al României. The legislative body that approved the publication of the Romanian energy performance standards C107 – 2005, Mc001 – 2006, C107/6-02 and C107-02, along with their annexes and modifications is the Ministry of Transport, Constructions and Tourism (Ministerul Transporturilor, Construc iilor i Turismului). The content of the standards was elaborated by the following Romanian institutions: The University of Architecture and Urban Planning “Ion Mincu” – Bucharest (Universitatea de Arhitectura i Urbanism ”Ion Mincu” – Bucure ti), The Institute for Research in Buildings and Building Economy – Bucharest (Institutul de Cercetari în Construc ii i Economia Construc iilor INCERC – Bucure ti), The Associastion of the Building Service Engineers from Romania (Asocia ia Inginerilor de Instala ii din România – AIIR) and The Technical University of Civil Engineering – Bucharest (Universitatea Tehnica de Construc ii – Bucure ti). [less ▲]

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