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See detailAnalysis of the technical / economic performance of four cropping systems involving Jatropha curcas L. in the Kinshasa Region (Democratic Republic of the Congo)
Minengu, J.D.; Mobambo, P.; Mergeai, Guy ULg

in Tropicultura (2015), 33(2),

In order to assess the sustainability of cultivating Jatropha curcas L. in rural areas in the Kinshasa region, four cropping systems were compared : cultivation of J. curcas as a sole crop with and ... [more ▼]

In order to assess the sustainability of cultivating Jatropha curcas L. in rural areas in the Kinshasa region, four cropping systems were compared : cultivation of J. curcas as a sole crop with and without fertilisers, a combination of J. curcas with subsistence crops (maize - Zea mays L., the common bean - Phaseolus vulgaris L.) with and without fertilisers. The major attacks by pests (mainly Aphthona sp.) suffered by J. curcas plants in the region make it vital to conduct at least two insecticide treatments per year. Dry seed yields of J. curcas obtained in the 4th year of cultivation amounted to 753 kg ha-1 when J. curcas was cultivated as a sole crop without fertilisers, 797 kg ha-1 for intercropping without fertilisers, 1158 kg ha-1 when J. curcas was cultivated as a sole crop with fertilisers and 1173 kg ha-1 for intercropping with fertilisers. Yields from the two annual crops were not improved by the application of mineral fertilisers on the J. curcas plants. They amounted to an average of 815 kg ha-1 for maize and 676 kg ha-1 for the beans. It is more profitable to cultivate J. curcas with maize and beans than to cultivate it as a sole crop. By combining crops in this way, a one-hectare farm can earn 1102 USD ha-1 without fertilisers and 1049 USD ha-1 with fertilisers. Sustainable cultivation of J. curcas under the test conditions requires the development of efficient weed / pest control methods and improved soil fertility management, in order to minimise the use of mineral fertilisers. [less ▲]

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See detailPituitary MRI characteristics in 297 acromegaly patients based on T2-weighted sequences.
Potorac, Iulia ULg; PETROSSIANS, Patrick ULg; Daly, Adrian ULg et al

in Endocrine-related cancer (2015)

Context: Responses of GH-secreting adenomas to multimodal management of acromegaly varies widely between patients. Understanding the behavioral patterns of GH-secreting adenomas by identifying predictive ... [more ▼]

Context: Responses of GH-secreting adenomas to multimodal management of acromegaly varies widely between patients. Understanding the behavioral patterns of GH-secreting adenomas by identifying predictive factors of their evolution is a research priority. Objective: To clarify the relationship between adenoma T2-weighted signal on diagnostic MRI in acromegaly and clinical and biological features at diagnosis. Design: International, multicenter, retrospective analysis. Setting: 10 endocrine tertiary referral centers. Patients: 297 acromegalic recently diagnosed patients with available diagnostic MRI evaluations were included in the study. Main outcome measure: Clinical, biochemical characteristics and MRI signal findings. Results: T2-hypointense adenomas represented 52.9% of the series, were smaller than their T2-hyper- and isointense counterparts (p<0.0001), were associated with higher IGF1 levels (p=0.0001), invaded the cavernous sinus less frequently (p=0.0002) and rarely caused optic chiasm compression (p<0.0001). Acromegalic men tended to be younger at diagnosis than women (p=0.067) and presented higher IGF1 values (p=0.01). Although in total, adenomas had a predominantly inferior extension in 45.8% of cases, in men this was more frequent (p<0.0001), whereas in women optic chiasm compression of macroadenomas occurred more often (p=0.0067). Most adenomas (45.1%) measured between 11-20mm in maximal diameter and bigger adenomas were diagnosed at younger ages (p=0.0001). Conclusions: T2-weighted signal differentiates GH-secreting adenomas into subgroups with particular behaviors. This raises the question of whether T2-weighted signal could represent a factor in the classification of acromegalic patients in future studies. [less ▲]

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See detailMutation de l'image, mutation de l'intention ? L'impact des représentations numériques en composition architecturale
Cunin, Maxime; Yang, Maria C.; Elsen, Catherine ULg

in de Boissieu, Aurélie; Deshayes, Catherine (Eds.) Actes du colloque "Mutations du Projet - Milieux et Cultures Numériques" (2015)

Les architectes ont toujours eu recours à de multiples représentations pour générer, faire évoluer puis communiquer leurs concepts architecturaux (tant aux pairs qu’aux usagers, ou encore aux décideurs ... [more ▼]

Les architectes ont toujours eu recours à de multiples représentations pour générer, faire évoluer puis communiquer leurs concepts architecturaux (tant aux pairs qu’aux usagers, ou encore aux décideurs). Cet article envisage comment la représentation externe impacte la perception « naïve » d’une intention architecturale, les « non experts » assumant des rôles de plus fondamentaux au sein de certains mécanismes décisionnels. Comment l’image, en pleine mutation depuis l’ère du numérique, façonne-t-elle la perception des facteurs clés (ou « attributs ») d’une intention architecturale ? L’article résume les principaux résultats d’une enquête menée en ligne via l’interface « Amazon Mechanical Turk » et générant 790 échelles d’évaluation de 6 avant-projets architecturaux. Les résultats abordent l’analyse des données en regard des différentes attributs; en regard des trois types de représentation choisies et en regard enfin des inconsistances dont font preuve les architectes eux-mêmes, étant donné l’évaluation de leurs propres projets et représentations. Ils révèlent que les attributs ne sont pas équitablement propices à un transfert d’intention exclusivement graphique et que les formes plus abstraites de représentations constituent, dans certains contextes, le moyen le plus efficace pour le transfert fidèle d’une intention architecturale. [less ▲]

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See detailEfficacy and cost-effectiveness: A study of different treatment approaches in a tertiary pain centre
VANHAUDENHUYSE, Audrey ULg; Gillet, Aline ULg; MALAISE, Nicole ULg et al

in European Journal of Pain (London, England) (2015)

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See detailRoasted Sunflower Kernel Paste (Tahini) Stability: Storage Conditions and Particle Size Influence
Muresan, Vlad; Danthine, Sabine ULg; Bolboaca, Sorana D. et al

in Journal of the American Oil Chemists' Society (2015)

Sunflower tahini faces quality problems due to the tendency of oil to exudate, causing accelerated rancidity and low marketability. In this study, the colloidal and oxidative stability of different ... [more ▼]

Sunflower tahini faces quality problems due to the tendency of oil to exudate, causing accelerated rancidity and low marketability. In this study, the colloidal and oxidative stability of different trimodal particle size distributions of sunflower tahini (cumulative volume percentages of small, middle and large class populations of 9.61–16.67, 43.03–55.03 and 47.36–28.3) was evaluated during storage at three different temperatures. Decreasing sample particle size decreased the sunflower tahini colloidal stability. The coarsest prototype, being the most stable tahini in terms of oil separation, was included in the oxidative stability storage test together with a commercial tahini. The peroxide values of the studied sunflower tahini samples increased significantly (p < 0.05) with storage time, irrespective of storage temperature, while the p-anisidine values showed an irregular pattern. Considering 30-meq O2/kg as a PV limit, the commercial tahini showed good oxidative stability as it was under this when stored 3 months at 4 °C, 2 months at room temperature and 1 month a 40 °C. The coarsest tahini sample was under the limit when stored 2 months at 4 °C, 1 month at room temperature and 2 weeks at 40 °C. Particle size was shown to be an essential parameter for controlling sunflower tahini’s overall stability. [less ▲]

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See detailMultiple timescale spectral analysis
Denoël, Vincent ULg

in Probabilistic Engineering Mechanics (2015), 39(0), 69--86

Abstract Spectral analysis is a classical tool for the structural analysis of structures subjected to random excitations. The most common application of spectral analysis is the determination of the ... [more ▼]

Abstract Spectral analysis is a classical tool for the structural analysis of structures subjected to random excitations. The most common application of spectral analysis is the determination of the steady-state second order cumulant of a linear oscillator, under the action of a stationary loading prescribed by means of its power spectral density. There exists however a broad variety of such similar problems, extending the concept to multi degree-of-freedom systems, non Gaussian excitation, slightly nonlinear oscillators or even transient excitations. In this wide class of problems, the cumulants of the response are obtained as the result of the integral of corresponding spectra over the frequency space, which is possibly multidimensional. Application of standard numerical integration techniques may be prohibitive, a reason why the spectral approach is often left aside. Besides, many engineering problems involve a clear timescale separation, usually of those pertaining to the loading and to the mechanical behavior of the system. In these problems, a proper consideration of the timescale separation results in dropping the order of integration by one, at least. This offers the possibility to derive analytical solutions, whenever the order of integration drops to zero, or to make numerical integration competitive. The paper presents this general method, together with some applications in wind and marine engineering. [less ▲]

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See detailHydromechanical behaviour of bentonite under in situ conditions
Dieudonné, Anne-Catherine ULg; Talandier, Jean; Collin, Frédéric ULg et al

Conference (2015)

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See detailInvestigating word recognition in intercomprehension: methods and findings
Möller, Robert ULg; Zeevaert, Ludger ULg

in Linguistics (2015), 53(2), 313352

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See detailImpact of stone content on soil moisture measurement with capacitive sensors 10HS (Decagon)
Deraedt, Deborah ULg; Bernard, Julien ULg; Biettlot, Louise ULg et al

in Geophysical Research Abstracts (2015), 17

Lot of soil survey focused on agricultural soils. For practical reasons, those soils have a low stone content. So, most of the soil water content sensors are placed on low stone content soils and the ... [more ▼]

Lot of soil survey focused on agricultural soils. For practical reasons, those soils have a low stone content. So, most of the soil water content sensors are placed on low stone content soils and the calibration equations are developed for them. Yet some researches take an interest in forest soils that are often much different from the previous ones. The differences lie in their stone content and their slope. Lots of studies have proved the importance of making soil specific calibration of the soil water content sensor. As our lab use regularly the 10HS sensors (Decagon Devices, United States) in forested soil, we decided to evaluate the importance of the stone content in the soil moisture measurement. The soil used for this experimentation comes from Gembloux (50◦33’54.9”N, 4◦42’11.3”E). It is silt that has been sieved at 2 mm to remove the gravel. The stones used to form the samples come from an experimental site located in the Belgian Ardennes (50◦1’52.6”N, 4◦53’22.5”E). They are mainly composed of schist with some quartz and sandstone elements. Initially, only five samples were constructed with three replications each. The size and the proportion of stones were the variables. Stones were classified in two groups, the first contains gravels whose size is less than 1,5 cm and a the second contains gravels whose size is comprised between 2 and 3 cm. The proportions of stone selected for the experiment are 0, 20 and 40%. In order to generate validation data, two more samples were constructed with intermediate proportion of stone content (30%). The samples were built in PVC container which dimensions are slightly bigger than the sensor volume of influence (1.1-1.3l). The soil samples were saturated and then dried on a thermal chamber set at about 32◦C. During at least 14 days, the samples soil water content was determined by the sensor measurement with the Procheck read-out system (Decagon Devices, United State) and by weighting the samples thrice a day. The evolution of the soil sample height was monitored as well. As first result, the stone content is a parameter that seems to influence soil water content. The stone size is no important. Because soil moisture deserves to be measured accurately in every soil and to confirm the first results the experiment is going on with more samples, different stone proportions, other sensor positioning and a natural air drying. [less ▲]

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See detailContact resistance problems applying ERT on low bulk density forested stony soils Is there a solution?
Deraedt, Deborah ULg; Touzé, Camille; Robert, Tanguy et al

in Geophysical Research Abstracts (2015), 17

Electrical resistivity tomography (ERT) has often been put forward as a promising tool to quantify soil water and solute fluxes in a non-invasive way. In our experiment, we wanted to determine ... [more ▼]

Electrical resistivity tomography (ERT) has often been put forward as a promising tool to quantify soil water and solute fluxes in a non-invasive way. In our experiment, we wanted to determine preferential flow processes along a forested hillslope using a saline tracer with ERT. The experiment was conducted in the Houille watershed, subcatchment of the Meuse located in the North of Belgian Ardennes (50˚1’52.6”N, 4˚53’22.5”E). The climate is continental but the soil under spruce (Picea abies (L.) Karst.) and Douglas fire stand (Pseudotsuga menziesii (Mirb.) Franco) remains quite dry (19% WVC in average) during the whole year. The soil is Cambisol and the parent rock is Devonian schist covered with variable thickness of silty loam soil. The soil density ranges from 1.13 to 1.87 g/cm3 on average. The stone content varies from 20 to 89% and the soil depth fluctuates between 70 and 130 cm. The ERT tests took place on June 1st 2012, April 1st, 2nd and 3rd 2014 and May 12th 2014. We used the Terrameter LS 12 channels (ABEM, Sweden) in 2012 test and the DAS-1 (Multi-Phase Technologies, United States) in 2014. Different electrode configurations and arrays were adopted for different dates (transect and grid arrays and Wenner – Schlumberger, Wenner alpha and dipole-dipole configurations). During all tests, we systematically faced technical problems, mainly related to bad electrode contact. The recorded data show values of contact resistance above 14873 Ω (our target value would be below 3000 Ω). Subsequently, we tried to improve the contact by predrilling the soil and pouring water in the electrode holes. The contact resistance improved to 14040 Ω as minimum. The same procedure with liquid mud was then tested to prevent quick percolation of the water from the electrode location. As a result, the lower contact resistance dropped to 11745 Ω. Finally, we applied about 25 litre of saline solution (CaCl2, 0.75g/L) homogeneously on the electrode grid. The minimum value of contact resistance reduced to 5222 Ω. This improved the contact resistance substantially, but complicates the execution of a pulse tracer experiment. To date we did not find any better solution to this problem and we keep searching a way to improve the contact resistance in stony forested soils with very low bulk density. We would like to exchange on these questions with EGU attendees in order to improve the experimental design or point out a new research path for these specific conditions. This could lead to enhance the use of ERT in soils with low density and high stone content. [less ▲]

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See detailTax evasion and social information: an experiment in Belgium, France, and the Netherlands
Pestieau, Pierre ULg

in International Tax and Public Finance (2015), 22

We experimentally study how receiving information about tax compliance of others affects individuals’ occupational choices and subsequent evading decisions. In one treatment individuals receive ... [more ▼]

We experimentally study how receiving information about tax compliance of others affects individuals’ occupational choices and subsequent evading decisions. In one treatment individuals receive information about the highest tax evasion rates of others in past experimental sessions with no such social information; in another treatment they receive information about the lowest tax evasion rates observed in the past sessions with no such social information. We observe an asymmetric effect of social information on tax compliance. Whereas examples of high compliance do not have any disciplining effect, we find evidence that examples of low compliance significantly increase tax evasion for certain audit probabilities. No major differences are found across countries [less ▲]

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See detailTagging with leisure needs
Pestieau, Pierre ULg; Racionero, Maria

in Social Choice and Welfare (2015)

We study optimal redistributive taxes when individuals differ in two characteristics—earning ability and leisure needs—assumed to be imperfectly correlated. Individuals have private information about ... [more ▼]

We study optimal redistributive taxes when individuals differ in two characteristics—earning ability and leisure needs—assumed to be imperfectly correlated. Individuals have private information about their abilities but needs are observable. With different levels of observable needs the population can be separated into groups and needs may be used as a tag.We first assume that the social planner considers individuals should be compensated for their leisure needs and characterize the optimal redistributive policy, and the extent of compensation for needs, with tagging.We also consider an alternative social objective where individuals are deemed responsible for their needs. [less ▲]

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See detailObservations sur la forme, l'état du support et la mise en page du P.Vat.gr. 11
Carlig, Nathan ULg

in Amato, Eugenio; Marganne, Marie-Hélène (Eds.) Le traité "Sur l'exil" de Favorinos d'Arles. Papyrologie, philologie et littérature (2015)

Observations sur le papyrus de Favorinos, son état de conservation et ses caractéristiques de forme et de mise en page, effectuées après autopsie du rouleau à la Biblioteca Apostolica Vaticana

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See detailIdentification of nonlinear normal modes of engineering structures under broadband forcing
Noël, Jean-Philippe ULg; Renson, Ludovic ULg; Grappasonni, Chiara ULg et al

in Mechanical Systems & Signal Processing (2015)

The objective of the present paper is to develop a two-step methodology integrating system identification and numerical continuation for the experimental extraction of nonlinear normal modes (NNMs) under ... [more ▼]

The objective of the present paper is to develop a two-step methodology integrating system identification and numerical continuation for the experimental extraction of nonlinear normal modes (NNMs) under broadband forcing. The first step processes acquired input and output data to derive an experimental state-space model of the structure. The second step converts this state-space model into a model in modal space from which NNMs are computed using shooting and pseudo-arclength continuation. The method is demonstrated using noisy synthetic data simulated on a cantilever beam with a hardening-softening nonlinearity at its free end. [less ▲]

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See detailSartre et l'instinct de mort
Cormann, Grégory ULg

in Gyemant, Maria; Popa, Delia (Eds.) Approches phénoménologiques de l'inconscient (2015)

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See detailAnalysis of high frequency geostationary ocean colour data using DINEOF
Alvera Azcarate, Aïda ULg; Vanhellemont, Quinten; Ruddick, Kevin et al

in Estuarine Coastal & Shelf Science (2015), 159

DINEOF (Data Interpolating Empirical Orthogonal Functions), a technique to reconstruct missing data, is applied to turbidity data obtained through the Spinning Enhanced Visible and Infrared Imager (SEVIRI ... [more ▼]

DINEOF (Data Interpolating Empirical Orthogonal Functions), a technique to reconstruct missing data, is applied to turbidity data obtained through the Spinning Enhanced Visible and Infrared Imager (SEVIRI) on board Meteosat Second Generation 2. The aim of this work is to assess if the tidal variability of the southern North Sea in 2008 can be accurately reproduced in the reconstructed dataset. Such high frequency data have not previously been analysed with DINEOF and present new challenges, like a strong tidal signal and long night-time gaps. An outlier detection approach that exploits the high temporal resolution (15 min) of the SEVIRI dataset is developed. After removal of outliers, the turbidity dataset is reconstructed with DINEOF. In situ Smartbuoy data are used to assess the accuracy of the reconstruction. Then, a series of tidal cycles are examined at various positions over the southern North Sea. These examples demonstrate the capability of DINEOF to reproduce tidal variability in the reconstructed dataset, and show the high temporal and spatial variability of turbidity in the southern North Sea. An analysis of the main harmonic constituents (annual cycle, daily cycle, M2 and S2 tidal components) is performed, to assess the contribution of each of these modes to the total variability of turbidity. The variability not explained by the harmonic fit, due to the natural processes and satellite processing errors as noise, is also assessed. [less ▲]

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