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See detailIdentification of the main parameters controlling the plasticity of ceramic pastes: The case study of the Marrakech region (Morocco)
El Boudour El Idrissi, Hicham ULg; Daoudi, Lahcen; Fontaine, François ULg et al

Poster (2015, June)

Numerous traditional ceramic workshops occur within a range of 10 to 80 km around the city of Marrakech. Our study aims to identify the main parameters controlling the plasticity of pastes used by the ... [more ▼]

Numerous traditional ceramic workshops occur within a range of 10 to 80 km around the city of Marrakech. Our study aims to identify the main parameters controlling the plasticity of pastes used by the artisans. To reach this goal, we characterize by X-ray diffraction, granulometry and plasticity index (PI) the local raw clayey material. The investigation of 26 whole pastes shows the dominance of quartz (20 to 50%) and clay minerals (25 to 60%) with K-feldspar (2 to 17%), plagioclase (2 to 25%), calcite (0 to 18%), dolomite (0 to 15%), goethite (0 to7%) and trace of hematite and anhydrite (< 3%). Amphibole occurs in trace (< 5%) but only in some samples. The clay minerals are diversified, including illite (10 to 40%), kaolinite (2 to 15%), mixed-layer (ML) (0 to 10%), smectite, vermiculite and chlorite (0 to 5%), and pyrophyllite-talc association (0 to 8%). Sepiolite (12%) is only present in one paste. The grain size is made by variable proportions of sand (5 to 65%), silt (12 to 53%) and clayey fraction (18 to 66%). The Plasticity index (PI) indicates the presence of two principals groups of pastes. (1) The first group is characterized by PI values ranging between 15 to 18. Their moderate plasticity behavior is related either to the low rate of clayey fraction and/or to the absence of plastic clays like smectites and mixed layer with smectitic sheets. (2) The PI of second group ranges between 20 to 32. The high plasticity values are influenced by the presence of specific clayey minerals like talc-pyrophyllite or sepiolite, or by the high content of smectite plus smectitic mixed-layers within the clayey (< 2 micron) fraction. Only one sample without any of these plastic minerals but with a high content of clayey fraction is characterized by a high PI value (24). We concluded that the workability of ceramic paste in Marrakech region is controlled by a combination of factors, dominated by the grain size distribution and the content in plastic clay minerals within the fine fraction. [less ▲]

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See detailGenetic depletion of the dual specificity protein phosphatase DUSP3 promotes LLC Lung tumour metastasis
Vandereyken, Maud ULg; Amand, Mathieu; Van Overmeire, Eva et al

Poster (2015, June)

DUSP3, also called Vaccinia-H1 Related (VHR) is a small dual specificity phosphatase dephosphorylating both tyrosine and serine/threonine phosphorylated residues. DUSP3 plays an important role in cell ... [more ▼]

DUSP3, also called Vaccinia-H1 Related (VHR) is a small dual specificity phosphatase dephosphorylating both tyrosine and serine/threonine phosphorylated residues. DUSP3 plays an important role in cell cycle regulation and is up-regulated in several human cancers. The physiological role of this phosphatase is, however, poorly understood. We have recently generated a DUSP3 knockout mouse by homologous recombination. The obtained mice have no spontaneous phenotype or pathology. However, DUSP3 deficiency prevented neo-vascularization of subcutaneously transplanted Matrigel plugs and Lung Lewis Carcinoma (LLC) tumours, suggesting an involvement of DUSP3 in tumour angiogenesis. Considering the importance of angiogenesis in metastatic formation, our study aimed to investigate the role of DUSP3 in metastatic dissemination. To do so, we used the LLC experimental metastasis model that shortcuts the intravasation/extravasation processes by injecting intravenously the LLC and the B16 (metastatic melanoma cell line) cells. Surprisingly, LLC, but not B16, lung metastasis developed twice faster in DUSP3-KO than WT mice. The enhanced LLC metastatic growth in DUSP3-/- mice was transferable to WT mice via DUSP3-/- bone marrow adoptive transfer, suggesting an involvement of the hematopoietic compartment in the observed phenotype. This was confirmed by a higher infiltration of neutrophils and macrophages in the lungs of DUSP3-KO compared to WT mice after LLC injection. This infiltration was correlated with higher expression of the chemokine receptor CCR2 in LLC-bearing DUSP3-KO lungs macrophages. Interestingly, LLC, but not B16 cells, were found to secrete high level of CCL2/MCP1, the CCR ligand chemokine. In line with this observation, we found that DUSP3-/- bone marrow derived-macrophages have a higher migration potential in response to LLC, but not B16, -conditionned medium. Altogether, our results suggest that DUSP3 plays an important role in metastatic dissemination/growth by a mechanism involving the control of CCR2-CCL2 chemoattraction axis in macrophages. [less ▲]

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See detailAuroral Morphologies of Jupiter and Saturn
Grodent, Denis ULg

Conference (2015, May 31)

We review the principal differences and similarities of the morphologies of Jupiter and Saturn's auroral emissions. We then show some examples of UV images that are expected to be acquired with Cassini ... [more ▼]

We review the principal differences and similarities of the morphologies of Jupiter and Saturn's auroral emissions. We then show some examples of UV images that are expected to be acquired with Cassini UVIS at Saturn and Juno UVS at Jupiter. [less ▲]

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Peer Reviewed
See detailComparing central western Europe Mesolithic and Neolithic plant processing microwear on flint tool
Linton, Jimmy ULg; Guéret, Colas; Gassin, Bernard

Conference (2015, May 30)

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See detailTowards an experiment based protocol for extracting and identifying residues
Cnuts, Dries ULg; Rots, Veerle ULg

Conference (2015, May 29)

Residue analysis has recently become a widely applied method in reconstructing the lifecycle of prehistoric stone tools. The identification of residues is traditionally based on the distinctive ... [more ▼]

Residue analysis has recently become a widely applied method in reconstructing the lifecycle of prehistoric stone tools. The identification of residues is traditionally based on the distinctive morphologies of the residue fragments by means of light microscopy. The majority of residue fragments, however, tend to have an amorphous structure and are therefore not easy to identify. In addition, some residue categories can only be detected by using transmitted light microscopy, which requires the extraction of residues from the tool’s surface. Yet another challenge is to determine whether the residues were deposited on the tool’s surface as a result of use or due to other processes. Here we present the results of an experimental study that addresses these methodological issues. Stone tools from a new experimental reference collection were used to test 6 different analytical methods: the observation of residues on stone tools with incident light microscopy, dry sampling using tweezers and brushes, wet sampling with micropipettes using distilled water and a tri-mixture of acetonitrile, ethanol and water, and extraction with an ultrasonic scaler or bath. The experiments demonstrate that the choice of a particular extraction procedure may influence the amount and types of residues that are extracted. This implies that the analytical method has an impact on the results of a residue analysis. Building on these data, we designed a new protocol, which was subsequently submitted to blind testing in order to test its accuracy and precision. Certain key attributes were also identified that may prove useful in distinguishing between use-related and natural residues. We discuss the importance of adapting analytical protocols to the research question of the study. [less ▲]

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See detailToward a more precise terminology for impact damage and an improved understanding of hunting weapons: First results from a large scale systematic experiment
Coppe, Justin ULg; Rots, Veerle ULg

Conference (2015, May 29)

Projectile points have recently taken an important place in debates on the complexity of Palaeolithic human behaviour. While the appearance of hunting weapons in the archaeological record was an important ... [more ▼]

Projectile points have recently taken an important place in debates on the complexity of Palaeolithic human behaviour. While the appearance of hunting weapons in the archaeological record was an important element in the past, current discussions focus a lot on the appearance of particular hunting methods. Distinctions are made between simple and complex weaponry, the latter assumed to be linked with modern humans only. While most of the identifications of hunting weapons in the archaeological record rely on the examination of so-called diagnostic impact damage, no reliable reference yet exist for distinguishing between hunting methods. We present the first results of a large-scale and systematic experiment that intends to address hunting weapons in a systematic way. A thorough survey of the literature has highlighted some existing ambiguity in current terminological frameworks for describing impact fractures. Based on our experiments, we propose some attributes that may be relevant for improving these terminologies. Attention will also be devoted to the design and conceptual framework of our experimental program and to some first results concerning the essential variables influencing damage formation. The overall goal is to improve our understanding of the different fracture phenomena and their variability in order to enhance the reliability of the identification of hunting weapons and perhaps of their projecting mode. [less ▲]

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See detailAgisme et jeunisme: Conséquences méconnues sur la santé de nos aînés et sur nos actes de soins
Missotten, Pierre ULg; Flamion, Allison ULg

Conference given outside the academic context (2015)

Conférence-débat autour de la question "Agisme et jeunisme: Conséquences méconnues sur la santé de nos aînés et sur nos actes de soins". Présentation basée sur les études scientifiques existantes à ce ... [more ▼]

Conférence-débat autour de la question "Agisme et jeunisme: Conséquences méconnues sur la santé de nos aînés et sur nos actes de soins". Présentation basée sur les études scientifiques existantes à ce jour sur ce qu'est l'âgisme, quelles sont ses conséquences sur la personne âgée, sur ses interlocuteurs et sur la relation qui se noue entre eux. [less ▲]

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Peer Reviewed
See detailQuelles caractéristiques du passage à la retraite ont un impact sur la cognition du sujet âgé ? Résultats de la cohorte AMI
Grotz, Catherine ULg; Matharan, Fanny; Amieva, Hélène et al

Conference (2015, May 29)

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See detailTable-ronde autour de l'ouvrage : M. Hagelstein, "Origine et survivances des symboles. Warburg, Cassirer, Panofsky"
Hagelstein, Maud ULg

Scientific conference (2015, May 29)

Table-ronde - échange questions/réponses - avec la participation de : Muriel VAN VLIET, Raphaël GÉLY, Rudy STEINMETZ, Alievtina HERVY, Bruno LECLERCQ

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See detailTime and aspect: what the academic grammars say, and what the texts actually show
Winand, Jean ULg

Scientific conference (2015, May 29)

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See detailFragmentation urbaine à travers les réseaux techniques
Cabrera Quispe, Juan Edson ULg

Doctoral thesis (2015)

Since about three decades ago, the networking services (water, energy, transport and telecommunications) are the subject of studies and mainly reforms (liberalization, privatization and concessions to ... [more ▼]

Since about three decades ago, the networking services (water, energy, transport and telecommunications) are the subject of studies and mainly reforms (liberalization, privatization and concessions to private companies, etc.) and also an important economic policy issue. However the possible effects of these reforms on the fragmentation or integration of urban societies are still poorly studied, although some studies (mainly on developing cities) support the thesis that there would be a growing urban fragmentation, reinforced by the dominant modes of implementing reforms network services. One of the most important theses about the subject is in a relatively recent development of the English authors Stephen Graham and Simon Marvin (2001). Their work generalizes the motion of fragmentation (splintering Urbanism) to all network services and a set of economic regions in the world. While this thesis presents consistency and validity - since it is known that the application of models of decentralization and liberalization of services has an effect on the fragmentation - the position of fragmentation due to centralized networks is inside a new analysis framework and still incomplete considering the absence of more empirical evidence. The thesis of fragmentation from centralized networks suggests that powerful factors are contributing to the disintegration of infrastructure, favoring the fragmentation of the social structure and material of cities. In fact, this breakdown of infrastructures makes possible many strategies of evasion; they are addressed to connect powerful users and valorized spaces, preventing the connection with less powerful users and poor spaces. These processes lead to the creation of spaces from different social networks, resulting in social elites living every day in places disconnected from the urban structure of the set (in gated communities, new complex people and other planned communities), as well as the lower classes, but the latter with the worst conditions. The main hypothesis of the "splintering Urbanism" argues that network services have an integrated character and are precisely the privatization and liberalization of services that contribute to the breakdown of network infrastructure and urban fragmentation feed. The control of networks from powerful coalitions of actors, separation and segmentation boost infrastructure in different network elements and service pack (2001: 141). This separation would occur across strategies "bypass" or "wrap" seeking to connect users, valuable or powerful places, and through discarding or dodge weaker users and worthless places. Our thesis "Urban Fragmentation through technical networks," confirms and reinforces the thesis made by Graham & Marvin, across expounding on the Cochabamba Bolivian context, a set of technical networks of small-scale or micro decentralized networks which are managed by autonomous social organizations that also fragment the territory without the need for "by pass" and the socio-spatial differentiation, but through the realization of strategies linked to autonomous administration and management of common and basic goods like water. This thesis demonstrates the existence of processes of spatial dislocation and loss of solidarity (main evils of urban fragmentation) across the dynamics of technical devices and decentralized networks infrastructure services from private-community water and small scale. However, our work describes in its urban development, territorial and environmental problems inside the phenomenon. The paper first presents a set of theories that attempt to explain the fragmentation and its particularities, then describes the socio-spatial formation of the study area whose characteristics allow this type of phenomenon, to arrive to a section that exposes all the particularities of the management water from public and local actors, analyzed from the environmental logic of urban water cycle, including the specifics of the main stage of study of this thesis, the municipality of Quillacollo in Cochabamba. From a spatial perspective, the thesis exhibits the characteristics of urban fragmentation across technical networks, exposing the details related to the organization of urban space as a result of processes of spatial dislocation, loss of solidarity and exercise of territoriality in small networks. It is concluded in a discussion about the validity of the strategies in terms of access to the resource, the possibilities of intervention and reflections about the power relationships among fragments and for water control. Finally, as a supplement, urban fragmentation through small technical networks, also allows to display the tensions between two ways of managing the territory (centralized view from the public sector and decentralized vision from local communities) highlighting the uncomfortable and marginalized urban planning position, but challenging the urbanism to recover to action on the highly fragmented contemporary cities with complex scenarios of governance and sometimes rare or endangered resources. [less ▲]

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See detailAntitrust and The challenge of policing « moligopolists »
Petit, Nicolas ULg

Conference (2015, May 29)

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See detailUnravelling Cemip expression and functions in the auditory portion of the inner ear.
Czajkowski, Amandine ULg; Chariot, Alain ULg; Delacroix, Laurence ULg et al

Poster (2015, May 29)

The inner ear is a complex organ composed of the vestibular system – which is the balancing system – and the cochlea – which is the earing system. The cochlea is a coiled shape organ composed of three ... [more ▼]

The inner ear is a complex organ composed of the vestibular system – which is the balancing system – and the cochlea – which is the earing system. The cochlea is a coiled shape organ composed of three main structures: the spiral ligament sitting on top of the stria vascularis, the organ of Corti with sensory hair cells and supporting cells and the spiral ganglion composed of neurons and glial cells. After an auditory stimulus, the sound wave progresses in the scala media filled with endolymph and induces a stimulation of sensory hair cells. These cells then transmit the information to the spiral ganglion neurons connected to them. Of course, the correct ionic homeostasis of endolymph is required for a good sound wave transmission. This homeostatic function is assured by the stria vascularis and the spiral ligament. The alteration of one of the structures mentioned before induces deafness. Currently, numerous genes have been associated to this kind of hearing loss. In the present work, we focus our attention Cemip – also known as KIAA1199 – that has been associated to human hereditary neurosensory deafness. Indeed, three missense mutations consisting in non-synonymous amino acid changes (R187L, R187H and H783Y) have been associated to this form of deafness. Therefore we would like to understand the role of Cemip in the cochlea. For that we have analysed Cemip mRNA pattern of expression by in situ hybridization at different developmental stages on cochlear sections. It seems Cemip mRNA is not present in the auditory portion of the inner ear at early embryonic stage 14 (E14) while it is largely present at E17 in the spiral ganglion, in supporting cells of the organ of Corti and in the spiral ligament. This expression is maintained post-nattily until P7. At P21 the expression is restricted to the spiral lamina - an osseous structure surrounding the spiral ganglion. Our on going work is aimed at revealing the biological role of Cemip in the cochlea in conditional knock-out mice. [less ▲]

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See detailUne nouvelle cause génétique d'acromégalie
Beckers, Albert ULg

Scientific conference (2015, May 29)

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See detailL'influence des conditions astrophysiques sur la chimie interstellaire
De Becker, Michaël ULg

Learning material (2015)

Detailed reference viewed: 11 (0 ULg)