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See detailNatural patches in Posidonia oceanica meadows: the seasonal biogeochemical pore water characteristics of two edge types
Abadie, A; Borges, Alberto ULg; Champenois, Willy ULg et al

in Marine Biology (2017), 164:166

Seagrass meadows can be assimilated to seascape matrixes encompassing a mosaic of natural and anthropogenic patches. Natural patches within the Mediterranean Posidonia oceanica meadows show a structural ... [more ▼]

Seagrass meadows can be assimilated to seascape matrixes encompassing a mosaic of natural and anthropogenic patches. Natural patches within the Mediterranean Posidonia oceanica meadows show a structural particularity which consist in a duality of their edge types. One edge is eroded by bottom currents, while the adjacent meadow colonizes the bare sediments. This study aims to study the dynamics of these two edges through the investigation of the biogeochemistry (pH, total alkalinity, dissolved inorganic carbon, CO2, CH4, N2O, H2S, dissolved inorganic nitrogen, PO4 3−) within vegetated and unvegetated sediments. These observations are compared with the adjacent meadow to have a better understanding of the colonization processes. Our results reveal that the P. oceanica matrix shows differences from the vegetated edges of sand patches, especially with regard to nutrient availability, which is generally more important at the colonized edge (dissolved inorganic nitrogen up to 65.39 μM in June). A clear disparity also occurs between the eroded and colonized edge with both a seasonal and bathymetrical variation of leaf biomass with higher disparities at 10 m in June (colonized edge 1415 gDW m−2; eroded edge 1133 gDW m−2). Themost important contrasts during this study were assessed in June, suggesting that the warm period of the year is more suitable for sampling to highlight disparate characteristics in temperate seagrass meadows. These findings put into light the potential importance of biogeochemical processes in the dynamics of natural patch edges. We hypothesize that they may influence the structural dynamics of P. oceanica seascapes. [less ▲]

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See detailQuality evaluation of peach chips and anticancer activity of pectin extracted from chips dehydrated by explosion puffing drying
Lyu, Jian ULg

Doctoral thesis (2017)

The objectives of this research are to discriminate the overall quality level of peach and nectarine chips prepared by explosion puffing drying (EPD), determine the changes of texture and water soluble ... [more ▼]

The objectives of this research are to discriminate the overall quality level of peach and nectarine chips prepared by explosion puffing drying (EPD), determine the changes of texture and water soluble pectin (WSP) during EPD processing and study the anticancer activity of WSP on malignant mesothelioma (MM). Principle component analysis (PCA), Analytic hierarchy process (AHP), K-mean cluster and Discriminant analysis (DA) are used to distinguish the overall quality level of peach and nectarine chips and get the characteristic evaluation indicators, which of them (e. g. rehydration ratio and expansion ratio) are corresponding to texture properties of dehydrated products. Additionally, biochemical changes of the cell wall (e. g. pectin) are also related to texture changes. The investigate on the changes of texture and WSP at different stages of EPD processing in which osmotic dehydration (OD) was used as the pretreatment, show that OD with the appropriated concentration can improve the texture quality of dried products. The drying processing causes the degradation and structure modification of WSP, which can induce apoptosis in MM cells. EPD technology can be carried out as a potential pathway on modification of pectin, which may contribute to the development of a potential therapy against MM. [less ▲]

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See detailIntraspecific variation of Zn hyperaccumulation in Arabidopsis halleri populations
Schvartzman Echenique, Maria Sol ULg; Corso, Massimiliano; Fataftah, Nazeer ULg et al

Conference (2017, July 19)

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See detailItem purification versus adjustments for multiple comparisons in DIF detection
Drabinova, Adela; Martinkova, Patricia; Magis, David ULg

Poster (2017, July 18)

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See detailCompte-rendu de l'ouvrage de J. van der Steen: Memory Wars in the Low Countries, 1566-1700
Regibeau, Julien ULg

in Émulations. Revue des jeunes chercheuses et chercheurs en sciences sociales (2017)

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See detailmstR: An R package to generate multistage testing designs
Magis, David ULg; Yan, Duanli; von Davier, Alina

Conference (2017, July 18)

Multistage testing (MST; Yan, von Davier & Lewis, 2014) has become an important framework of tailored testing. Similarly to computerized adaptive testing (CAT) it proposes an optimal routing of the ... [more ▼]

Multistage testing (MST; Yan, von Davier & Lewis, 2014) has become an important framework of tailored testing. Similarly to computerized adaptive testing (CAT) it proposes an optimal routing of the administered items according to the previous test taker’s responses. However, items are not selected and administered as single units but as modules (subsets). The main goal of MST consists in selecting the optimal path of modules across the successive stages of the test. Unfortunately, if various operational testing programs are nowadays considering MST for practical administrations, there is still very limited access to accurate software that can either treat or generate MST scenarios for research purposes. In this talk we succinctly present a new package from the R software, called mstR (Magis, Yan & von Davier, 2017). Built in the same spirit of the package catR for CAT designs, it permits to generate repeated response patterns under a predefined MST scenario by providing the set of modules and related item parameters, the number of stages and the connections between modules from successive stages. Several rules for optimal module selection and ability estimation (under IRT framework or based on test scores) are also available. This talk will mostly focus on the (non-technical) description of package mstR and its main features. An example will also be described as an illustration of this framework. [less ▲]

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See detailNegative velocity fluctuations and non-equilibrium fluctuation relation for a driven high critical current vortex state
Bag, Biplab; Shaw, Gorky ULg; Banerjee, S. S. et al

in Scientific Reports (2017), 7(1), 5531

Under the influence of a constant drive the moving vortex state in 2H-NbS2 superconductor exhibits a negative differential resistance (NDR) transition from a steady flow to an immobile state. This state ... [more ▼]

Under the influence of a constant drive the moving vortex state in 2H-NbS2 superconductor exhibits a negative differential resistance (NDR) transition from a steady flow to an immobile state. This state possesses a high depinning current threshold ( $$\boldsymbolI_\boldsymbolc^\boldsymbolh$$ I c h ) with unconventional depinning characteristics. At currents well above $$\boldsymbolI_\boldsymbolc^\boldsymbolh$$ I c h , the moving vortex state exhibits a multimodal velocity distribution which is characteristic of vortex flow instabilities in the NDR regime. However at lower currents which are just above $$\boldsymbolI_\boldsymbolc^\boldsymbolh$$ I c h , the velocity distribution is non-Gaussian with a tail extending to significant negative velocity values. These unusual negative velocity events correspond to vortices drifting opposite to the driving force direction. We show that this distribution obeys the Gallavotti-Cohen Non-Equilibrium Fluctuation Relation (GC-NEFR). Just above $$\boldsymbolI_\boldsymbolc^\boldsymbolh$$ I c h , we also find a high vortex density fluctuating driven state not obeying the conventional GC-NEFR. The GC-NEFR analysis provides a measure of an effective energy scale (E eff ) associated with the driven vortex state. The E eff corresponds to the average energy dissipated by the fluctuating vortex state above $$\boldsymbolI_\boldsymbolc^\boldsymbolh$$ I c h . We propose the high E eff value corresponds to the onset of high energy dynamic instabilities in this driven vortex state just above $$\boldsymbolI_\boldsymbolc^\boldsymbolh$$ I c h . [less ▲]

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See detailPrevention Library and Resources in four languages (QP Library)
Comité de Bibliografía en Prevención Cuaternaria; WONCA SIG P4 & O; Pizanelli, Miguel et al

Textual, factual or bibliographical database (2017)

Since Quaternary Prevention is very extensive and complex, during the design process for database input, an indexing structure with the use of coding tools and categories was considered. This design will ... [more ▼]

Since Quaternary Prevention is very extensive and complex, during the design process for database input, an indexing structure with the use of coding tools and categories was considered. This design will allow the addition of materials and will provide easy access to them. To add documents, 13 data fields must be populated. To access the input data form, for the purpose of adding documents, use this link: http://j.tinyurl.com/P4-Library To avoid duplication of data entries, it is necessary to review and perform an audit. In the beginning, we will provide this tutorial to a few data entry collaborators. To become a data entry collaborator, please send an e-mail to the following address: quaternaryprevention@gmail.com Charts are available in eight languages to code with Q-Codes: http://3cgp.docpatient.net/tabular/ [less ▲]

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See detailGlobal regression model for moisture content determination using near-infrared spectroscopy
Clavaud, Matthieu ULg; Roggo, Yves; Degardin, Klara et al

in European Journal of Pharmaceutics and Biopharmaceutics (2017)

Near-infrared (NIR) global quantitative models were evaluated for the moisture content (MC) determination of three different freeze-dried drug products. The quantitative models were based on 3822 spectra ... [more ▼]

Near-infrared (NIR) global quantitative models were evaluated for the moisture content (MC) determination of three different freeze-dried drug products. The quantitative models were based on 3822 spectra measured on two identical spectrometers to include variability. The MC, measured with the reference Karl Fischer (KF) method, were ranged from 0.05% to 4.96%. Linear and non-linear regression models using Partial Least Square (PLS), Decision Tree (DT), Bayesian Ridge Regression (Bayes-RR), K-Nearest Neighbors (KNN), and Support Vector Regression (SVR) algorithms were created and evaluated. Among them, the SVR model was retained for a global application. The Standard Error of Calibration (SEC) and the Standard Error of Prediction (SEP) were respectively 0.12% and 0.15%. This model was then evaluated in terms of total error and risk-based assessment, linearity, and accuracy. It was observed that MC can be fastly and simultaneously determined in freeze-dried pharmaceutical products thanks to a global NIR model created with different medicines. This innovative approach allows to speed up the validation time and the in-lab release analyses. [less ▲]

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See detailEffects of an experimental resource pulse on the macrofaunal assemblage inhabiting seagrass macrophytodetritus
Remy, François ULg; Gobert, Sylvie ULg; Lepoint, Gilles ULg

in Belgian Journal of Zoology (2017), 147(1), 1-15

Physical disturbances and resource pulses are major structuring drivers of terrestrial and aquatic ecosystems. The accumulations of exported dead leaves from the Neptune grass, Posidonia oceanica (L ... [more ▼]

Physical disturbances and resource pulses are major structuring drivers of terrestrial and aquatic ecosystems. The accumulations of exported dead leaves from the Neptune grass, Posidonia oceanica (L.) Delile are ephemeral and highly dynamic detrital habitats offering food sources and shelter for vagile macrofauna community. These habitats are frequently subject to wind and storms which can add “new” detrital material to previous accumulations; these can be defined as resource pulses and could potentially impact the associated macrofauna. This study assesses the impact of an experimental resource pulse on the macrofauna associated with exported P. oceanica litter accumulations. The experimental design consisted of two pulse treatments (the addition of dead leaves with and without the associated fauna), and two controls (one procedural, and one total control), where the added material was left underwater for 14 days. Invertebrates then present in the sampled detritus were all identified and counted. Our data suggest that the responses of these invertebrates to resource pulses present intermediate characteristics between aquatic and terrestrial ecosystems responses. Inputting a moderate amount of dead P. oceanica leaves into experimental mesocosms had a non-negligible impact and rapidly affected the macrofauna community. Specialist detritivores species were boosted while herbivore/detritivore species dramatically decreased. Predators also showed a modest but significant density increase, demonstrating the fast propagation of the pulse response throughout the entire community and through several trophic levels. Strict hypoxia-tolerant species were also only observed in the treated mesocosms, indicating the strong influence of resource pulses on physico-chemical conditions occurring inside litter accumulations. [less ▲]

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See detailCosmological Time, Entropy and Infinity
Hauret, Clémentine ULg; Magain, Pierre ULg; Biernaux, Judith ULg

in Entropy (2017), 19(7),

Time is a parameter playing a central role in our most fundamental modelling of natural laws. Relativity theory shows that the comparison of times measured by different clocks depends on their relative ... [more ▼]

Time is a parameter playing a central role in our most fundamental modelling of natural laws. Relativity theory shows that the comparison of times measured by different clocks depends on their relative motion and on the strength of the gravitational field in which they are embedded. In standard cosmology, the time parameter is the one measured by fundamental clocks (i.e., clocks at rest with respect to the expanding space). This proper time is assumed to flow at a constant rate throughout the whole history of the universe. We make the alternative hypothesis that the rate at which the cosmological time flows depends on the dynamical state of the universe. In thermodynamics, the arrow of time is strongly related to the second law, which states that the entropy of an isolated system will always increase with time or, at best, stay constant. Hence, we assume that the time measured by fundamental clocks is proportional to the entropy of the region of the universe that is causally connected to them. Under that simple assumption, we find it possible to build toy cosmological models that present an acceleration of their expansion without any need for dark energy while being spatially closed and finite, avoiding the need to deal with infinite values. [less ▲]

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See detailA Novel Accelerometer-Based Method for Stride Length Estimation
Boutaayamou, Mohamed ULg; Schwartz, Cédric ULg; Denoël, Vincent ULg et al

Poster (2017, July 14)

We demonstrate the feasibility of accurately and precisely estimating the left/right average stride length from measured heel/toe accelerations in the gait of healthy, old adults. Our approach relies on ... [more ▼]

We demonstrate the feasibility of accurately and precisely estimating the left/right average stride length from measured heel/toe accelerations in the gait of healthy, old adults. Our approach relies on (1) a novel method that uses only accelerometer data without the need of additional data from, e.g., gyroscopes and/or magnetometers, and on (2) the validation of the results using reference 3D optoelectronic system data. [less ▲]

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See detailUndoing Art
Delville, Michel ULg

Conference (2017, July 13)

Detailed reference viewed: 23 (1 ULg)