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See detailPhosphate-based composite electrodes for Li/Na-ion batteries: upscalable solution syntheses with in-situ solid carbon addition
Vertruyen, Bénédicte ULg; Brisbois, Magali; Eshraghi, Nicolas ULg et al

Conference (2016, September 22)

Since the success story of lithium iron phosphate, other phosphate-based compounds have attracted a lot of interest as promising candidates for positive electrodes in lithium-ion or sodium-ion batteries ... [more ▼]

Since the success story of lithium iron phosphate, other phosphate-based compounds have attracted a lot of interest as promising candidates for positive electrodes in lithium-ion or sodium-ion batteries. Their electronic conductivity usually has to be improved through the preparation of composite powders ensuring intimate contact between the active material and conductive carbon. We report on the one-step synthesis of composite precursors using spray-drying or hydrothermal synthesis routes, two techniques which offer easy scaling-up of production. We show that addition of a solid carbon source (carbon black or carbon nanotubes) into the solution has a strong influence on the powder microstructure and is very effective in improving the battery cycling performance, taking our recent results on phosphates [Fex(PO4)(OH)y.zH2O)] and fluorophosphates [Na2FePO4F, Na3V2(PO4)2F3] as examples. We also compare this approach with the addition of the carbon source as a soluble precursor (such as ascorbic acid or citric acid) where the in situ formation of carbon is achieved by a heat treatment in inert atmosphere (typically argon). [less ▲]

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See detailStructure and Dynamics of Ge-Se Liquids and Glasses under Pressure
Yildirim, Can ULg

Doctoral thesis (2016)

Among network forming glasses, chalcogenide glasses are of great importance not only for their optoelectronic applications, but also for the network structure that displays enhanced structural variability ... [more ▼]

Among network forming glasses, chalcogenide glasses are of great importance not only for their optoelectronic applications, but also for the network structure that displays enhanced structural variability due to the covalent bonding network. In this project, we study the Ge-Se binary alloy as the target system in order to investigate the structure and dynamics of the liquid and glassy phases under pressure by using a combination of ab initio molecular dynamics (AIMD) simulations and X-ray scattering experiments. The wide glass forming range of the GexSe100􀀀x system allows one to tune the stiffness of the network structure by increasing the mean coordination number with the Ge content which affects the macroscopic material properties such as resistance to aging, hardness, conductivity, and fragility. In this respect, we study 10 different AIMD generated and 5 experimentally produced (i.e melt quenching) compositions spanning the flexible-to-rigid elastic phase transitions according to Maxwell’s isostatic stability criterion. As for the liquid state, after having validated the structural models by comparing the experimental findings available, we examine the dynamics of Ge-Se melts at ambient pressure. The investigations on the diffusion coefficients and viscosity at 1050 K showed clear anomalies, departing from the expectation that atomic mobility should decrease as the system becomes more and more rigid. Furthermore, the relaxation behavior at 1050 K also shows similar anomalies when intermediate scattering factors are examined at q vector corresponding to the principal peak position of the total structure factor. To elucidate this anomaly, we discuss the effect of the topological constraints on the dynamics in liquid state. The results show that the isostatic systems have slower dynamics as compared to flexible and stressed rigid phases. Moreover, we speculate that the reason of this anomaly may originate from the distribution of the topological bond bending constraints of the higher coordinated species (i.e. Ge) results. In particular, the flexible, and stressed rigid compositions showed a high variance in the Ge bond bending constraints whereas the isostatic composition forms a network in which the bond bending constraints are homogeneously distributed. We link this behavior with a global fragility concept for network forming liquids in such a way that fragility minima are obtained both by experimental findings and the calculated fragility values of the AIMD generated compositions (i.e. VFT or MYEGA fits) when scaled to the isostatic composition for a number of different systems. As for the glassy phase, the AIMD generated structural models show good agreement in both real and reciprocal space. The equation of state and normalized stress-strain curves are compared to the available experiments in order to verify the pressure behavior of the simulations. The results show a good agreement. In addition to the simulations under pressure, we show results of X-ray absorption spectroscopy (XAS) and X-ray diffraction (XRD) experiments under pressure. Both simulations and the experiments show that there are no sign of crystallization during compression up to 42 GPa. One of the main important finding is the evolution of the Ge-Se bond length for the compositions studied. We observe a bond compression in the early stages of densification in the phase identified as low density amorphous (LDA), which is followed by an abrupt jump starting in pressures around 10-15 GPa, both in simulations and experiments. Furthermore, a semiconductor to metal transition is identified with the red shift in Ge K edge energy. The features of polyamorphism was also detected from the pressure evolution of the principal peak position of the structure factor which show two distinct slopes indicating different structural response to the applied pressure. In order to have a deeper understanding of the densification mechanisms, we apply neighbor analyses to our atomic trajectories and show that the tetrahedral to octahedral transformation (i.e LDA to HDA) starts to take place when the fifth and sixth neighbors effectively become the part of first shell neighbors, where the bond angles adapt themselves to 90 degrees. We furthermore speculate the effect of network rigidity of the glasses at ambient conditions onto the kinetics of the amorphous-amorphous transitions. It appears that the polyamorphic transitions are more sluggish as the network rigidity (i.e Ge content) increases. Finally we show that there is a universal threshold value in coordination change from LDA to HDA phases GexSe100􀀀x (where x 25) when scaled to reduced densities. [less ▲]

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See detailCoupled Boltzmann Equation Solver: Effects of the Electron-Phonon Interaction on the Transport Coefficients
Pike, Nicholas ULg; Dewandre, Antoine ULg; Verstraete, Matthieu ULg

Scientific conference (2016, September 22)

Recent experimental and theoretical calculations point to a complex interplay between the electron and phonon baths in a wide variety of materials [1,2]. We propose a method of coupling the Boltzmann ... [more ▼]

Recent experimental and theoretical calculations point to a complex interplay between the electron and phonon baths in a wide variety of materials [1,2]. We propose a method of coupling the Boltzmann equations for the electron and phonon baths within the relaxation time approximation which we use to calculate the thermoelectric transport coefficients. Our model for the coupled Boltzmann Equation solver includes analytic models, including ${\bf k \cdot p}$ Hamiltonians and tight-binding Hamiltonians, for both the electron and phonon energies and analytic models for the electron and phonon relaxation mechanisms. From these calculations we hope to better understand the role and interplay of electron-phonon and phonon-phonon interactions on the thermoelectric transport coefficients. [1] - Phys. Rev. Lett. ${\bf 114}$, 115901 (2015). [2] - PNAS ${\bf 112}$, 14777-14782 (2015). [less ▲]

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See detailNuclear Magnetic Resonance Metabolomic Profiling of Mouse Kidney, Urine and Serum Following Renal Ischemia/Reperfusion Injury.
Jouret, François ULg; Leenders, Justine ULg; Defraigne, Jean-Olivier ULg et al

in PLoS ONE (2016), 11(9), 1-14

Abstract BACKGROUND: Ischemia/reperfusion (I/R) is the most common cause of acute kidney injury (AKI). Its pathophysiology remains unclear. Metabolomics is dedicated to identify metabolites involved in ... [more ▼]

Abstract BACKGROUND: Ischemia/reperfusion (I/R) is the most common cause of acute kidney injury (AKI). Its pathophysiology remains unclear. Metabolomics is dedicated to identify metabolites involved in (patho)physiological changes of integrated living systems. Here, we performed 1H-Nuclear Magnetic Resonance metabolomics using urine, serum and kidney samples from a mouse model of renal I/R. METHODS: Renal 30-min ischemia was induced in 12-week-old C57BL/6J male mice by bilaterally clamping vascular pedicles, and was followed by 6, 24 or 48-hour reperfusion (n = 12/group). Sham-operated mice were used as controls. Statistical discriminant analyses, i.e. principal component analysis and orthogonal projections to latent structures (OPLS-DA), were performed on urine, serum and kidney lysates at each time-point. Multivariate receiver operating characteristic (ROC) curves were drawn, and sensitivity and specificity were calculated from ROC confusion matrix (with averaged class probabilities across 100 cross-validations). RESULTS: Urine OPLS-DA analysis showed a net separation between I/R and sham groups, with significant variations in levels of taurine, di- and tri-methylamine, creatine and lactate. Such changes were observed as early as 6 hours post reperfusion. Major metabolome modifications occurred at 24h post reperfusion. At this time-point, correlation coefficients between urine spectra and conventional AKI biomarkers, i.e. serum creatinine and urea levels, reached 0.94 and 0.95, respectively. The area under ROC curve at 6h, 24h and 48h post surgery were 0.73, 0.98 and 0.97, respectively. Similar discriminations were found in kidney samples, with changes in levels of lactate, fatty acids, choline and taurine. By contrast, serum OPLS-DA analysis could not discriminate sham-operated from I/R-exposed animals. CONCLUSIONS: Our study demonstrates that renal I/R in mouse causes early and sustained metabolomic changes in urine and kidney composition. The most implicated pathways at 6h and 24h post reperfusion include gluconeogenesis, taurine and hypotaurine metabolism, whereas protein biosynthesis, glycolysis, and galactose and arginine metabolism are key at 48h post reperfusion. [less ▲]

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See detailDouble-slit experiment in momentum space
Ivanov, Igor ULg; Seipt, Daniel; Surzhykov, Andrey et al

in Europhysics Letters (2016), 115(4), 41001

Young's classic double-slit experiment demonstrates the reality of interference when waves and particles travel simultaneously along two different spatial paths. Here, we propose a double-slit experiment ... [more ▼]

Young's classic double-slit experiment demonstrates the reality of interference when waves and particles travel simultaneously along two different spatial paths. Here, we propose a double-slit experiment in momentum space, realized in the free-space elastic scattering of vortex electrons. We show that this process proceeds along two paths in momentum space, which are well localized and well separated from each other. For such vortex beams, the (plane-wave) amplitudes along the two paths acquire adjustable phase shifts and produce interference fringes in the final angular distribution. We argue that this experiment can be realized with the present-day technology. We show that it gives experimental access to the Coulomb phase, a quantity which plays an important role in all charged particle scattering but which usual scattering experiments are insensitive to. [less ▲]

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See detailCompetition of phonon and magnon effects in the temperature dependence of spinwave stiffness
Ostler, Thomas ULg; Verstraete, Matthieu ULg; Di Gennaro, Marco ULg et al

Conference (2016, September 21)

Magnons are the elementary magnetic excitations in ordered solids. Understanding such collective excitations is important for a number of technologically relevant fields, such as, magnonics [1] or spin ... [more ▼]

Magnons are the elementary magnetic excitations in ordered solids. Understanding such collective excitations is important for a number of technologically relevant fields, such as, magnonics [1] or spin caloritronics [2]. The central interactions in spin caloritronics are the couplings of phonons with electrons and spin degrees of freedom. Furthermore, understanding the effects of temperature on the phonon and spin degrees of freedom adds a further complexity. In the present work we have developed a multiscale model of ferromagnetic materials and demonstrate the effect of temperature dependent phonon displacements on the magnons spectra. Our results show that the for Fe and Ni the effect of phonon displacements acts to reduce the Curie temperature, whereas for Permalloy the opposite is true due to an increased long-ranged exchange interaction. This increased exchange interaction results in an increasing spin-wave stiffness with increasing temperature, overcoming the usual decrease due to magnon softening. To determine the effects of increasing the phonon temperature we have developed a multiscale model whereby we begin by calculating the thermal displacement of phonons, $\sqrt{\langle u^2(T) \rangle}$, calculated using the phonopy software package [3] using electronic ground state and phonon properties determined using the ABINIT software package [4]. Then the exchange constants are determined using the SPRKKR package [5]. Finally, we use linear spin wave theory to determine the effect of the phonon temperature on the exchange alone, demonstrating an increasing frequency of the acoustic magnon branch. We take into account the thermal effects of the magnetic system through the use of the atomistic spin dynamics approach. Magnon softening due to thermal effects demonstrates a more modest increase in the exchange stiffness (over the purely phononic effect), however, an overall increase is still observed. \newline \newline [1] A. V. Chumak, V. I. Vasyuchka, A. A. Serga, and B. Hillebrands, Nature Physics, {\bf 11}, 453–461 (2015). \newline [2] G. E. W. Bauer, E. Saitoh, and B. J. van Wees, Nature Materials {\bf 11}, 391 (2012). \newline [3] Atsushi Togo and Isao Tanaka, Scr. Mater., {\bf 108}, 1-5 (2015) \newline [4] X. Gonze \textit{et al.} Computer Physics Communications {\bf 180}, 2582-2615 (2009). \newline [5] T. Huhne \textit{at al.} Physical Review B, {\bf 58}, 10236 (1998). [less ▲]

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See detailREFINEMENT OF PERI-ANAESTHESIA PRACTICES FOR LABORATORY ANIMAL CARE
Thomas, Aurélie ULg

Doctoral thesis (2016)

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See detailDie Familie von Medem. Zur Verbindung von Bildung, Literatur und Politik in Kurland
Leyh, Valérie ULg

Conference (2016, September 21)

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See detailThe role of meetings in building modern organisational governance systems - outlining a sociological approach to meetings
Thunus, Sophie ULg

Conference (2016, September 21)

By relying on empirical and micro level analyses of the implementation of a Belgian reform of mental healthcare delivery, this paper shows that inter-organisational and interinstitutional meetings might ... [more ▼]

By relying on empirical and micro level analyses of the implementation of a Belgian reform of mental healthcare delivery, this paper shows that inter-organisational and interinstitutional meetings might be conceived as key sites for the realisation of public policy objectives; i.e. sites where both the meaning of policy objectives and the social systems through which they are enacted are (re)defined. This paper is based on a case study on the implementation process of the ongoing Belgian reform of mental healthcare delivery, called “Reform 107”. Reform 107 is designed to shift mental healthcare organisation from the model of residential psychiatry, which is centred on medical hospital care, to community psychiatry that implies, instead, psychosocial home and/or ambulatory care. Policymakers conceived this shift through the development of local mental healthcare networks, which are defined as concrete partnerships between local, residential and ambulatory care providers and social and employment public services. The first stage in the implementation process consisted in four-year exploratory projects through which local actors were expected to refine the community care model proposed by policymakers. By asking local actors to participate in the adaptation of the model to local realities, policymakers intended to improve their own knowledge of local mental healthcare systems on the one hand, and to interest local actors in a reform that challenges their institutional interests on the other. Our analyses of the implementation of Reform 107 focused on three local exploratory projects and their monitoring by federal public health authorities. The empirical material was collected through semi-structured interviews (N=62) with policymakers and local actors, direct observations of the meetings between local mental health practitioners responsible for the reform’s implementation (N=65) and documentary analyses, including policy and (local) organisational documents. This material was first analysed by relying on a sociological frame of analysis based on the French sociology of organisations (Friedberg, 1997) and the interactionist sociology (Abbott, 2005; Bucher & Strauss, 1961; Corbin & Strauss, 2008). The resulting sociological account (Thunus, 2015) stressed that local models of governance, power struggles as well as professional knowledge significantly impacted on the development of mental healthcare networks. It also highlighted the use of new techniques by federal public health authorities to manage the reform implementation. Those techniques, including the multiplication of meetings with local actors, direct coaching of local projects’ leaders as well as training of front-line mental health professionals, were conceived as means to oppose strategies of resistance usually enacted by psychiatric hospitals (S Thunus & Schoenaers, 2012). This paper offers to refine this analysis by focusing on the specific role played by meetings in policy implementation, based on a conception of “the practice of policy-making”(Richard Freeman, Griggs, & Boaz, 2011). It draws on the observation that, though researches on policy implementation increasingly evoke meetings as part of the policy process, they do not properly address the role played by meeting in influencing, orienting and possibly (re)defining policy reforms. Indeed, following the recognition of the need for dealing with complex and uncertain problems, or wicked problems (Roberts, 2000), by relying on procedural policy instruments (Howlett, 2000) and collaborative governance (Emerson, Nabatchi, & Balogh, 2011), numerous researches focused on policy networks, hybrid forums (Callon, Lascoumes, & Barthes, 2001) and special committees whose activities involve meetings. However, by considering meetings as a part of/a tool for larger processes as problems solving, crisis resolution or decision-making, those researches made them unproblematic means to achieve predefined and external objectives. The problems resulting from a “meetings as a tool approach” (Schwartzman, 1989) are twofold. On the one hand, it seems to ignore that, by bringing different and specialised expertise together, meetings induce social, cognitive and technical challenges. Those challenges, including the sharing of specialised knowledge and harsh negotiations between actors defending institutional interests and professional jurisdictions, make meetings conflicting and problematic arenas (Cohen, March, & Olsen, 1972). On the other, when conceived as rational means to reach external objectives, meetings often appear as disappointing and pointless. Based on this observation, Schwartzman (1989) proposed to stop seeing meeting as part of larger processes as decision-making (as a tool), to focus on what meetings actually do to the organisation or social context in which they take place (i.e. to consider meetings as a topic). By drawing on Schwartzman’s invitation to make meetings a research topic, we propose to ask the question of what inter-organisational and interinstitutional meetings actually did to the Belgian mental health care reform. We suggest addressing that question by relying on a conception of policy-making as a practice of a special kind (R Freeman, Griggs, & Boaz, 2011). This conception insists on the role played by policy practices as meeting and talks in determining policy objectives and creating groups supporting them. Accordingly, we will focus on social actions and interactions unfolding through meetings and talks, to see how they use and produce knowledge, instruments and relationships both embodying and reshaping their environment. Finally, by inviting us to bracket the explicit objectives of the observed meetings (e.g. providing policymakers with an operational definition of care functions included in the proposed community model), this approach will enable us to see what inter-organisational and interinstitutional meetings actually do to policy reforms. That is, generating performances (Goffman, 1959) supporting collective enactments of new social and professional roles and artefacts that (re) constitute the meaning of the reform and the associated social system. Viewing meeting as a concrete policy practice thus helps to stress that they contribute to durable and deep change in their social environment, precisely by generating talks that largely exceed/displace their explicit mandate. [less ▲]

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See detailL’anosognosie dans la maladie d’Alzheimer: Soi, mémoire et jugement
Genon, Sarah ULg

Speech/Talk (2016)

Detailed reference viewed: 17 (1 ULg)
See detailSynthesis of poly(ionic liquid)-type nanogels, by cobalt-mediated radical cross-linking copolymerization for coating applications
Weiss-Maurin, Mathilde ULg

Doctoral thesis (2016)

To answer the increasing demand for long-lasting antibacterial polymeric coatings, this thesis explores a straightforward synthetic approach to cationically charged nanogels by cobalt-mediated radical ... [more ▼]

To answer the increasing demand for long-lasting antibacterial polymeric coatings, this thesis explores a straightforward synthetic approach to cationically charged nanogels by cobalt-mediated radical cross-linking copolymerization (CMRCcP), thus expanding previous works on the cobalt-mediated radical polymerization of poly(ionic liquid)s, or PILs. This method involves a vinyl monomer and a divinyl cross-linker, in presence of a complex of Cobalt(III) playing the role of both the initiator and the controlling agent. The syntheses of globular nanogels were first investigated under mild conditions, using a mono- and a divinyl co-monomer with similar reactivities. CMRCcP was implemented on either neutral (vinyl acetate (VAc) and divinyl adipate (DVA)) co-monomers, or hydrophilic (bromide-containing) ionic liquid co-monomers. Control over each polymerization was ascertained, and dormant cobalt-carbon chain-ends could be re-activated to form “second-generation” nanogels. CMRCcP of N-vinyl-3-ethyl imidazolium bromide (VEtImBr) and 1,13-divinyl-3-decyl diimidazolium bromide (DVImBr) was achieved in water at 30 °C, leading to hydrophilic poly(VEtImBr-co-DVImBr) nanogels. The antibacterial activity of these cross-linked structures was investigated, and an effect of architecture is detected. The hydrophobic pendants of these PIL-based nanogels were synthesized via direct CMRCcP in ethyl acetate, using bis(trifluromethanesulfonyl)imide (NTf2-) counter anions. An array of these poly(VEtImNTf2-co-DVImNTf2) nanogels was then investigated as possible coatings for porous patterned surfaces. Thin films of hydrophobic PIL-based nanogels were also evaluated in ionic conductivity tests. “Second-generation” nanogels exhibited better ionic conductivity, and were able to form better organized porous patterned surfaces than “first-generation” nanogels. Different cross-linked architecture were approached, using a mono- and a divinyl co-monomers of completely different reactivities: synthesizing poly(VEtImBr-co-DVA) nanogels met limited success, while copolymerizing VAc and DVImBr yielded too low conversion. A two-step arm-first process was implemented to form star-like poly(VEtImNTf2-co-DVImNTf2) nanogels with PVAc arms. [less ▲]

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See detailDealing with storm impacts on the forest sector through integrated and systemic approaches at the regional level
Riguelle, Simon ULg

Doctoral thesis (2016)

Wind is one the most damaging natural hazard that forests are facing worldwide and in Europe. Destructive storms lead to severe forest damage and consequently cause disruptions in daily forest management ... [more ▼]

Wind is one the most damaging natural hazard that forests are facing worldwide and in Europe. Destructive storms lead to severe forest damage and consequently cause disruptions in daily forest management and timber supply chains. Major dysfunctions can happen at each step of forest-wood chains and at each level of management, leading to huge economic losses and long-lasting crises within public organisations and private companies. In this context, the first part of this work aims at handling those complex and multi-facetted storm-related issues with new approaches in order to mitigate economic, environmental and societal impacts of storms on the forest-based sector. In a first step, an overview of risk management practices in forestry is presented, as well as major determinants of storm damage risk management. SWOT analyses are also used for highlighting main issues and opportunities in current windthrow management process. In a second step, an integrated framework is proposed for tackling those strategic issues and seizing opportunities arising from the uncertain decision-making context. A systemic perspective is also presented for managing storm damage risk at regional, national or supranational level with a holistic perspective. In regards to those original approaches, the thesis also highlights some of the crucial challenges public authorities might address for enhancing their affectivity in this process. In the second part of the manuscript, three particular aspects of storm damage management are considered: contingency planning, the development of decision-supporting tools for the forest community, and timber storage planning at the regional level. Those topics are illustrated by case studies taking place in Wallonia, Belgium. In particular, the development of a model-based decision support system (DSS) illustrate how systemic analysis can help on the one hand designing balanced strategies for the regional forest-based sector in case of severe wind damage and on the other hand identifying bottlenecks that should be solved before the next huge storm to enhance systemic resilience and resistance. Regarding timber conservation, a GIS-based methodology for locating optimal areas for sprinkling storage at the regional scale is presented, together with an applied study on the influence of anaerobic storage process on the quality of spruce logs. From a wider perspective, this thesis reveals that taking decision under uncertainty will remain a key challenge to address in forestry, especially in the context of climatic change. However, original methodologies focusing on systemic and integrated risk management approaches can help in this effort. Finally, the work emphasises the urgent need of effective risk management policies at regional, national, and international levels to guide researchers, forest managers and industrials. [less ▲]

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See detailCharacterization of Forests with LiDAR Technology
Michez, Adrien ULg; Bauwens, Sébastien ULg; Bonnet, Stéphanie ULg et al

in Baghdadi, Nicolas; Zribi, Mehrez (Eds.) Land Surface Remote Sensing in Agriculture and Forest (2016)

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See detailLa lutte contre le jihadisme et l' 'Etat islamique' : le cadre de droit constitutionnel
Behrendt, Christian ULg

Scientific conference (2016, September 20)

Conférence donnée lors de la Journée d'étude du "Centre d'Etude de Droit militaire et de Droit de la Guerre" de l'Ecole Royale Militaire, Bruxelles, campus de l'Ecole Royale Militaire, 20 septembre 2016.

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See detailRelationships between mind-wandering, personal goals processing, and future thinking.
Stawarczyk, David ULg; D'Argembeau, Arnaud ULg

Conference (2016, September 20)

Mind-wandering refers to the occurrence of thoughts whose content is both decoupled from stimuli present in the immediate environment and unrelated to the task currently being carried out. Although this ... [more ▼]

Mind-wandering refers to the occurrence of thoughts whose content is both decoupled from stimuli present in the immediate environment and unrelated to the task currently being carried out. Although this phenomenon has been the object of increasing interest from the scientific community during le last decade, proportionally few studies have attempted to clearly determine the form, content, and possible functions of this particular kind of cognitions. In this presentation, we will review recent evidence from studies mainly performed in our lab suggesting that most instances of mind-wandering refer to the anticipation and planning of future events and are also closely related to the processing of personal goals. More specifically, we will first discuss the findings from behavioral research that examined the phenomenological features of mind-wandering with the use of experience sampling procedures during laboratory tasks. Results of these studies mainly revealed that most of reported mind-wandering episodes are temporally oriented towards the future and that this ‘prospective bias’ can be increased when participants’ attention had been oriented toward their personal goals prior to performing the tasks. We will next review the results of neuroimaging studies that investigated the neural correlates of mind-wandering and we will more specifically focus on meta-analytic evidences suggesting that the neural correlates of mind-wandering strongly overlap with those associated with episodic future thinking and personal goal processing. Together, these results suggest that mind-wandering may have an important adaptive value and could in particular play a key role in planning and preparing for upcoming events related to the individuals’ personal goals. [less ▲]

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See detailT2-weighted MRI signal predicts hormone and tumor responses to somatostatin analogs in acromegaly.
Potorac, Iulia ULg; PETROSSIANS, Patrick ULg; Daly, Adrian ULg et al

in Endocrine-Related Cancer (2016), 23(11), 871881

GH-secreting pituitary adenomas can be hypo-, iso- or hyperintense on T2-weighted MRI sequences. We conducted the current multicenter study in a large population of patients with acromegaly to analyze the ... [more ▼]

GH-secreting pituitary adenomas can be hypo-, iso- or hyperintense on T2-weighted MRI sequences. We conducted the current multicenter study in a large population of patients with acromegaly to analyze the relationship between T2-weighted signal intensity on diagnostic MRI and hormonal and tumoral responses to somatostatin analogs (SSA) as primary monotherapy. Acromegaly patients receiving primary SSA for at least 3 months were included in the study. Hormonal, clinical and general MRI assessments were performed and assessed centrally. We included 120 patients with acromegaly. At diagnosis, 84, 17 and 19 tumors were T2-hypo-, iso- and hyperintense, respectively. SSA treatment duration, cumulative and mean monthly doses were similar in the three groups. Patients with T2-hypointense adenoma had median SSA-induced decreases in GH and IGF-1 of 88% and 59% respectively, which were significantly greater than the decreases observed in the T2-iso- and hyperintense groups (p<0.001). Tumor shrinkage on SSA was also significantly greater in the T2-hypointense group (38%) compared with the T2-iso- and hyperintense groups (8% and 3%, respectively; p<0.0001). The response to SSA correlated with the calculated T2-intensity: the lower the T2-weighted intensity, the greater the decrease of random GH (p<0.0001, r=0.22), IGF-1 (p<0.0001, r=0.14) and adenoma volume (p<0.0001, r=0.33). The T2-weighted signal intensity of GH-secreting adenomas at diagnosis correlates with the hormone reduction and tumor shrinkage in response to primary SSA treatment in acromegaly. This study supports its use as a generally available predictive tool at diagnosis that could help to guide subsequent treatment choices in acromegaly. [less ▲]

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See detailStudy on contribution of lipids towards the mechanical properties of milk fat globule membrane monolayer
Malik, Priyanka ULg; Danthine, Sabine ULg; Blecker, Christophe ULg

Conference (2016, September 20)

Milk fat globule membrane (MFGM) stabilizes fat globule in milk in form of emulsion. The primary monolayer of MFGM is rich in proteins and secondary bilayer is rich in polar lipids. MFGM finds application ... [more ▼]

Milk fat globule membrane (MFGM) stabilizes fat globule in milk in form of emulsion. The primary monolayer of MFGM is rich in proteins and secondary bilayer is rich in polar lipids. MFGM finds application as an additive in dairy and food industry (e.g. emulsions, infant formulas & reduced-fat products) for its emulsifying and stabilizing properties. MFGM received much attention in recent years due to both its health- beneficial & technological functionalities. This work has been carried out with the objective to understand contribution of various components towards the surface properties of complete MFGM. MFGM was isolated from fresh raw cream. During isolation of MFGM apart from polar lipids and MFGM proteins, neutral lipids are also isolated which have their origin in fat globules but are often considered as a constituent of MFGM. The MFGM was further fractioned into lipid fraction, defatted fraction and polar lipids. The mechanical properties of monolayer were studied for the above fractions using Langmuir film balance. Study of surface properties can also be linked to their techno-functional properties by calculating film elasticity of the compression isotherm which can be linked to emulsifying and stabilizing properties. The analysis of compression isotherms revealed that film elasticity is highly influenced by polar lipids. The behaviour of the MFGM appeared to be influenced by neutral lipid and defatted fraction during beginning of compression and by polar lipids at the end of compression. [less ▲]

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