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See detailFast and accurate modelling of longitudinal neuroimaging data
Guillaume, Bryan ULiege; Waldorp, Lourens; Nichols, Thomas

Speech/Talk (2012)

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See detailFast and accurate modelling of longitudinal neuroimaging data: an application to ADNI data
Guillaume, Bryan ULiege; Hua, Xue; Thompson, Paul et al

Poster (2013, June 10)

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See detailFast and accurate modelling of longitudinal neuroimaging data: an application to ADNI data
Guillaume, Bryan ULiege; Hua, Xue; Thompson, Paul et al

Poster (2013, June 17)

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See detailFast and accurate procedure for the determination of Cr(VI) in solid samples by isotope dilution mass spectrometry.
Fabregat Cabello, Neus ULiege; Rodriguez-Gonzalez, Pablo; Castillo, Angel et al

in Environmental Science & Technology (2012), 46(22), 12542-9

We present here a new environmental measurement method for the rapid extraction and accurate quantification of Cr(VI) in solid samples. The quantitative extraction of Cr(VI) is achieved in 10 minutes by ... [more ▼]

We present here a new environmental measurement method for the rapid extraction and accurate quantification of Cr(VI) in solid samples. The quantitative extraction of Cr(VI) is achieved in 10 minutes by means of focused microwave assisted extraction using 50 mmol/L Ethylendiamintetraacetic acid (EDTA) at pH 10 as extractant. In addition, it enables the separation of Cr species by anion exchange chromatography using a mobile phase which is a 1:10 dilution of the extracting solution. Thus, neutralization or acidification steps which are prone to cause interconversion of Cr species are not needed. Another benefit of using EDTA is that it allows to measure Cr(III)-EDTA complex and Cr(VI) simultaneously in an alkaline extraction solution. The application of a 10 minutes focused microwave assisted extraction (5 min at 90 degrees C plus 5 min at 110 degrees C) has been shown to quantitatively extract all forms of hexavalent chromium from the standard reference materials (SRM) candidate NIST 2700 and NIST 2701. A double spike isotope dilution mass spectrometry (IDMS) procedure was employed to study chromium interconversion reactions. It was observed that the formation of a Cr(III)-EDTA complex avoided Cr(III) oxidation for these two reference materials. Thus, the use of a double spiking strategy for quantification is not required and a single spike IDMS procedure using isotopically enriched Cr(VI) provided accurate results. [less ▲]

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See detailA fast and facile synthetic route toward the preparation of nanoparticles of polythiophene and its derivatives
Bozukova, Dimitriya; Jérôme, Robert ULiege; Jérôme, Christine ULiege

in Journal of Nanoparticle Research (2013), 15(4), 15831-18

A novel photochemical water-based approach for the preparation of nanoparticles of polymerized thiophene (Th), thiophene methanol (ThM), or their mixtures (Th-co/or-ThM) was developed. The influence of 3 ... [more ▼]

A novel photochemical water-based approach for the preparation of nanoparticles of polymerized thiophene (Th), thiophene methanol (ThM), or their mixtures (Th-co/or-ThM) was developed. The influence of 3-[(2-acryloyloxy)methyl] thiophene (ATh) as cross-link agent on the stability of the nanoparticles and on their performances was investigated. The occurrence of a polymerization process was confirmed by Fourier transform infrared (FT-IR), UV and fluorescence emission spectroscopies. Nanoparticles with very narrow size distribution (0.0092–0.105 ATh cross-linked, 0.0635–0.272 uncross-linked) and ideal spherical shape (radius 35–47 nm ATh cross-linked, 49–109 nm uncross-linked) were obtained whatever the reaction composition. The size of the particles was found to depend strongly on the level of ATh-stabilization and to diminish upon increase of the ATh content. In contrast, in the same order, their thermal stability shifted toward higher temperatures. Thermal decomposition of the nanoparticles led to formation of carbon-nanoobjects, as observed by transmission electron microscopy, FT-IR, and RAMAN spectroscopies. The re-dispersibility of the dry Th-co/or-ThM nanoparticles in some conventional monomers and solvents has been estimated. [less ▲]

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See detailFast and Famous: Looking for the fastest speed at which a face can be recognized
Barbeau, Emmanuel; Besson, Gabriel ULiege; Barragan-Jason, Gladys

in Journal of Vision (2013)

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See detailFast and famous: looking for the fastest speed at which a face can be recognized
Barragan-Jason, Gladys; Besson, Gabriel ULiege; Ceccaldi, Mathieu et al

in Frontiers in Psychology (2013), 4

Face recognition is supposed to be fast. However, the actual speed at which faces can be recognized remains unknown. To address this issue, we report two experiments run with speed constraints. In both ... [more ▼]

Face recognition is supposed to be fast. However, the actual speed at which faces can be recognized remains unknown. To address this issue, we report two experiments run with speed constraints. In both experiments, famous faces had to be recognized among unknown ones using a large set of stimuli to prevent pre-activation of features which would speed up recognition. In the first experiment (31 participants), recognition of famous faces was investigated using a rapid go/no-go task. In the second experiment, 101 participants performed a highly time constrained recognition task using the Speed and Accuracy Boost- ing procedure. Results indicate that the fastest speed at which a face can be recognized is around 360–390 ms. Such latencies are about 100 ms longer than the latencies recorded in similar tasks in which subjects have to detect faces among other stimuli. We discuss which model of activation of the visual ventral stream could account for such latencies. These latencies are not consistent with a purely feed-forward pass of activity throughout the visual ventral stream. An alternative is that face recognition relies on the core network underlying face processing identified in fMRI studies (OFA, FFA, and pSTS) and reentrant loops to refine face representation. However, the model of activation favored is that of an activation of the whole visual ventral stream up to anterior areas, such as the perirhinal cortex, combined with parallel and feed-back processes. Further studies are needed to assess which of these three models of activation can best account for face recognition. [less ▲]

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See detailFast and high yield recovery of arabinose from destarched wheat bran
Aguedo, Mario ULiege; Vanderghem, Caroline ULiege; Goffin, Dorothée ULiege et al

in Industrial Crops & Products (2013), 43

Enzymatically destarched wheat bran (DWB) contained 13.8% of arabinose and 23.1% xylose. Up to a maximum of 70% of the arabinose was progressively released from DWB when heated at 80 or 100°C in media ... [more ▼]

Enzymatically destarched wheat bran (DWB) contained 13.8% of arabinose and 23.1% xylose. Up to a maximum of 70% of the arabinose was progressively released from DWB when heated at 80 or 100°C in media acidified with HCl. Whereas microwave irradiation at higher temperatures in pressure vessels could lead to higher yields of extraction. A Box-Behnken experimental design established an efficient model describing the effects of temperature, irradiation duration and pH on arabinose extraction. The pH appeared as the most important factor of the process. 4-5 min of microwave heating at 150ºC and pH 1 appeared as a fast and highly efficient method to recover more than 90% of the arabinose of DWB. When plotting the percentages of arabinose against the combined severity factors LogR’0 (calculated from the temperature/duration/pH conditions applied), two different fitting profiles were obtained for both the heating techniques. Under microwave heating, high free xylose’s release could also occur. The experimental design led to a quadratic model predicting the release of xylose from DWB. A range of conditions enabled to minimize xylose and hydrolyze around 50% of the total arabinose, yielding a high purity fraction. An alternative would be to release more than 90% of both arabinose and xylose, for further arabinose purification or for a common valorization of both pentoses. [less ▲]

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See detailFast and not furious: an inquiry into the current low-risk/high-gain configuration of public participation
Rosskamp, Benedikt ULiege; Delvenne, Pierre ULiege; Charlier, Nathan ULiege et al

Conference (2016, June 29)

For several years scholars pointed at the development of a “participatory turn” in science, technology and innovation (STI). Decisively informed by STS, “public involvement” and then “public engagement” ... [more ▼]

For several years scholars pointed at the development of a “participatory turn” in science, technology and innovation (STI). Decisively informed by STS, “public involvement” and then “public engagement” with STI have been enacted in a broad array of participatory experiments across Europe. These experiments were usually informed by rhetoric of citizen empowerment and distributed governance, against the limitations of technocratic approaches and traditional innovation processes, in order to “enrich”, “deepen”, “broaden” the knowledge base of our democracies. As “embarked researchers”, STS scholars played a crucial role in facilitating and legitimizing the organization of participatory events engaging a variety of publics. This paper will rely on the knowledge and expertise we gathered when organizing multiple participatory events over the last decade, while still trying maintain a critical distance with regard to our own engagement and the types of participation we contributed to enact. More specifically, we propose to draw on the lessons learnt from two recent projects, the organization of a citizens’ summit (Europe Wide Views on Sustainable Consumption) and a prospective study to gauge the potential of involving users in a Living Lab in the health sector in Wallonia. These two projects produced different publics (“citizens-consumers” or “users”), were informed by different political rationales (“sustainability” or “inclusive innovation”), took place in diverse settings (a European FP7 project or a project funded by the Walloon Region) and connected to several narratives of public empowerment through participation (“being heard in policymaking” or “accelerating and improving health”). Our contribution maps and compares the different instrumental and strategic framings of the engagement of publics in those two projects, emphasizing the roles attributed to fabricated publics but also the construction of categories such as the “state” and the “economy”. It unpacks some critical issues related to the methods and techniques used in the concrete implementation of participatory exercises such as, for example, the relation between the assigned tasks, the allowed forms of dialogue between the participants, the room for engagement with the issue(s) at stake and the broader understanding of processes these inputs were supposed to contribute to. Our analysis highlights a tension between the justificatory rationales for public engagement and its specific enactments. In these fast and optimized exercises, participants and their inputs become resources that need to be methodologically maximized and from which “value” may be extracted for instrumental use, i.e. innovation or policy-making. In this configuration in which, we argue, most participation experiments are stuck, the increasing involvement of publics in either policy-making or innovation will only be likely to produce low risk and high gain for powerful actors, who manage to take the best advantage of unpaid and uncritical labour from participants. Due attention (including self-reflexive critique) will be paid to alternative framings and critical insights, which were methodologically eliminated or ‘tamed’ to avoid threatening the design of the overall participatory exercise. By externalizing critique to favour unconditional compliance with imposed notions of the “greater good”, we scrutinize the risk for participation to become a mere space of experimentation for the sake of innovation and economic growth. Furthermore, we argue that critical scholarly work should help to move beyond this particular division of labour and responsibilities between the spheres of science, society and the state in order to avoid re-enacting traditional conceptions of the policy-making process and innovation pathways. [less ▲]

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See detailFast and powerful heritability inference for family-based neuroimaging studies.
Ganjgahi, Habib; Winkler, Anderson ULiege; Glahn, David C. et al

in NeuroImage (2015), 115

Heritability estimation has become an important tool for imaging genetics studies. The large number of voxel- and vertex-wise measurements in imaging genetics studies presents a challenge both in terms of ... [more ▼]

Heritability estimation has become an important tool for imaging genetics studies. The large number of voxel- and vertex-wise measurements in imaging genetics studies presents a challenge both in terms of computational intensity and the need to account for elevated false positive risk because of the multiple testing problem. There is a gap in existing tools, as standard neuroimaging software cannot estimate heritability, and yet standard quantitative genetics tools cannot provide essential neuroimaging inferences, like family-wise error corrected voxel-wise or cluster-wise P-values. Moreover, available heritability tools rely on P-values that can be inaccurate with usual parametric inference methods. In this work we develop fast estimation and inference procedures for voxel-wise heritability, drawing on recent methodological results that simplify heritability likelihood computations (Blangero et al., 2013). We review the family of score and Wald tests and propose novel inference methods based on explained sum of squares of an auxiliary linear model. To address problems with inaccuracies with the standard results used to find P-values, we propose four different permutation schemes to allow semi-parametric inference (parametric likelihood-based estimation, non-parametric sampling distribution). In total, we evaluate 5 different significance tests for heritability, with either asymptotic parametric or permutation-based P-value computations. We identify a number of tests that are both computationally efficient and powerful, making them ideal candidates for heritability studies in the massive data setting. We illustrate our method on fractional anisotropy measures in 859 subjects from the Genetics of Brain Structure study. [less ▲]

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See detailFast And Reliable Chromatographic Procedure For The Purification Of Virginiamycin M-1 Factor
Nott, Katherine ULiege; Paquot, Michel ULiege; Heilporn, Sylvie et al

in Chromatographia (2002), 56(5-6),

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See detailFast and Reliable Method for the Preparation of Various [18F]Fluorobenzyl Halides
Lemaire, Christian ULiege; Libert, Lionel ULiege; Plenevaux, Alain ULiege et al

in Journal of Labelled Compounds & Radiopharmaceuticals (2009, July), 52(S1), 178

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See detailFast and sharp decrease in calprotectin predicts remission by infliximab in anti-TNF naive patients with ulcerative colitis.
De Vos, M.; Dewit, Olivier; D'Haens, G. et al

in Journal of Crohn’s and Colitis [=JCC] (2012), 6(5), 557-62

AIM: To evaluate the effect of infliximab induction therapy on calprotectin levels in patients with ulcerative colitis (UC). PATIENTS AND METHODS: In this prospective study 53 patients with active UC from ... [more ▼]

AIM: To evaluate the effect of infliximab induction therapy on calprotectin levels in patients with ulcerative colitis (UC). PATIENTS AND METHODS: In this prospective study 53 patients with active UC from 17 centers were treated with infliximab therapy (5 mg/kg) at baseline, week 2, and week 6. Faecal calprotectin was measured every week. Sigmoidoscopies were performed at baseline, week 6 and week 10. RESULTS: Median calprotectin levels decreased from 1260 (IQR 278.5- 3418) at baseline to 72.5 (IQR 18.5 - 463) at week 10 (p<0.001). After 10 weeks, infliximab therapy induced endoscopic remission and a decrease in calprotectin to<50 mg/kg or at least a 80% decrease from baseline level in 58% of patients. A significant and steep decrease of calprotectin levels was seen at week 2 for patients with an endoscopic remission at week 10 as compared to patients who did not show a remission. (p<0.001). At week 10 an excellent correlation was found between endoscopic remission and clinical Mayo score reflected by an AUC of ROC analyses of 0.94 (0.87-1) and with calprotectin measurements (AUC 0.91 (0.81-1)) : all patients with calprotectin levels <50 mg/kg, and a normal clinical Mayo score (=0) were in endoscopic remission. CONCLUSIONS: Infliximab induces a fast and significant decrease of faecal calprotectin levels in anti-TNF naive patients with ulcerative colitis predictive for remission of disease. [less ▲]

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See detailA fast and simple method for simultaneous measurements of 25(OH)D, 24,25(OH)2D and the Vitamin D Metabolite Ratio (VMR) in serum samples by LC-MS/MS (powerpoint)
Fabregat Cabello, Neus ULiege; Farre Segura, Jordi ULiege; Huyghebaert, Loreen ULiege et al

Scientific conference (2017, September)

We present here a rapid, easy, reliable and cost-effective method for the quantification of 25-hydryxoyvitamin D2 and D3, epi-25-hydroxyyvitamin D3 and 24,25-dihydroxyvitamin D3 by LC-MS/MS in serum ... [more ▼]

We present here a rapid, easy, reliable and cost-effective method for the quantification of 25-hydryxoyvitamin D2 and D3, epi-25-hydroxyyvitamin D3 and 24,25-dihydroxyvitamin D3 by LC-MS/MS in serum samples. The proposed methodology has been strongly validated with both NIST and Labquality materials, obtaining mean intra-assay and inter-assay imprecision lower than 6 and 6.4% and mean recoveries within 95-104%. Besides we have compared satisfactorily samples from Vitamin D Standardization Program (n=80) with reference values and patient samples (n=281) with our reference LC-MS/MS method. The proposed methodology is prepared to be used in routine testing and permits the calculation of the Vitamin D Metabolite Ratio (VMR). [less ▲]

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See detailA fast and simple method for simultaneous measurements of 25(OH)D, 24,25(OH)2D and the Vitamin D Metabolite Ratio (VMR) in serum samples by LC-MS/MS
Fabregat Cabello, Neus ULiege; Farre Segura, Jordi ULiege; Huyghebaert, Loreen ULiege et al

in Clinica Chimica Acta (2017)

BACKGROUND: Rapid, easy and reliable measurement of the major vitamin D metabolites is required in order to fulfill the needs of a clinical routine laboratory. To overcome these challenges, we have ... [more ▼]

BACKGROUND: Rapid, easy and reliable measurement of the major vitamin D metabolites is required in order to fulfill the needs of a clinical routine laboratory. To overcome these challenges, we have developed and validated a LC-MS/MS method for the quantification of 25-hydroxyvitamin D2 and D3, epi-25-hydroxyvitamin D3 and 24,25-dihydroxyvitamin D3. METHODS: Sample preparation was based on precipitation and centrifugation of 100 µL of patient serum, followed by injection into the LC-MS/MS system. Samples from Vitamin D Standardization Program (n=80) and patient samples (n=281) have been compared with a reference LC-MS/MS method. For the analytical validation NIST and Labquality quality control materials were used. RESULTS: Mean intra-assay and inter-assay imprecision were less than 6.0 and 6.4% and mean recoveries were within 95-104%. LOQ’s were 0.5 µg/L for 24,25(OH)2D3, 1.1 µg/L for 25(OH)D3 and epi-25(OH)D3 and 1.7 µg/L for 25(OH)D2. A 3% bias obtained between the proposed and the reference method satisfies Vitamin D Standardization Program recommendations. CONCLUSIONS: We present a rapid, easy, reliable and cost-effective method completely adequate for routine testing, which permits the measurement of the ratio of 24,25-dihydroxyvitamin D to 25-hydroxyvitamin D, Vitamin D Metabolite Ratio (VMR), in serum samples. [less ▲]

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See detailFast and slow spindle involvement in the consolidation of a new motor sequence
Barakat, M.; Doyon, J.; Debas, K. et al

in Behav Brain Res (2011), 217(1), 117-21

This study aimed to determine the distinct contribution of slow (11-13 Hz) and fast (13-15 Hz) spindles in the consolidation process of a motor sequence learning task (MSL). Young subjects (n = 12) were ... [more ▼]

This study aimed to determine the distinct contribution of slow (11-13 Hz) and fast (13-15 Hz) spindles in the consolidation process of a motor sequence learning task (MSL). Young subjects (n = 12) were trained on both a finger MSL task and a control (CTRL) condition, which were administered one week apart in a counterbalanced order. Subjects were asked to practice the MSL or CTRL task in the evening (approximately 9:00 p.m.) and their performance was retested on the same task 12h later (approximately 9:00 a.m.). Polysomnographic (PSG) recordings were performed during the night following training on either task, and an automatic algorithm was used to detect fast and slow spindles and to quantify their characteristics (i.e., density, amplitude, and duration). Statistical analyses revealed higher fast (but not slow) spindle density after training on the MSL than after practice of the CTRL task. The increase in fast spindle density on the MSL task correlated positively with overnight performance gains on the MSL task and with difference in performance gain between the MSL and CTRL tasks. Together, these results suggest that fast sleep spindles help activate the cerebral network involved in overnight MSL consolidation, while slow spindles do not appear to play a role in this mnemonic process. [less ▲]

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See detailFast and slow tracks in lysozyme folding: Insight into the role of domains in the folding process
Matagne, André ULiege; Radford, S. E.; Dobson, C. M.

in Journal of Molecular Biology (1997), 267(5), 1068-1074

The folding of lysozyme involves parallel events in which hydrogen exchange kinetics indicate the development of persistent structure at very different rates. We have monitored directly the kinetics of ... [more ▼]

The folding of lysozyme involves parallel events in which hydrogen exchange kinetics indicate the development of persistent structure at very different rates. We have monitored directly the kinetics of formation of the native molecule by the binding of a fluorescently labelled inhibitor, MeU-diNAG (4-methylumbelliferyl-N,N'-diacetyl-beta-D-chitobioside). The data show that native character monitored in this way also develops with different timescales. Although the rate determining step on the slow pathway (similar to 75% of molecules at pH 5.5, 20 degrees C) can be attributed to the need to reorganise structure formed early in the folding process, the data indicate that the rate determining step on the fast track (involving similar to 25% of molecules) involves the docking of the two constituent domains of the protein. In the fast folding track the data are consistent with a model in which each domain forms persistent structure prier to their docking in a locally cooperative manner on a timescale comparable to the folding of small single domain proteins. (C) 1997 Academic Press Limited. [less ▲]

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See detailFast Atmospheric Plasma Deposition of Bio-Inspired Catechol/Quinone-Rich Nanolayers to Immobilize NDM-1 Enzymes for Water Treatment
Mauchauffé, Rodolphe; Bonot, Sébastien; Moreno-Couranjou, Maryline et al

in Advanced Materials Interfaces (2016), 3(8), 101002

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See detailFast automated extraction and clean-up of biological fluids for polychlorinated dibenzo-p-dioxins, dibenzofurans and coplanar polychlorinated biphenyls analysis
Focant, Jean-François ULiege; De Pauw, Edwin ULiege

in Journal of Chromatography. B : Analytical Technologies in the Biomedical & Life Sciences (2002), 776(2), 199-212

A fast automated extraction and clean-up procedure for low-level analysis of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and coplanar polychlorinated biphenyls (cPCBs ... [more ▼]

A fast automated extraction and clean-up procedure for low-level analysis of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and coplanar polychlorinated biphenyls (cPCBs) in biological fluids is presented. Online extraction of prepared fluids is carried out using disposable octadecyl bonded (C-18) solid-phase extraction columns. Extracts are then cleaned up through disposable multi-layer silica (acidic, basic and neutral) and dispersed PX-21 carbon columns. This new methodology is compared with classical Soxhlet extraction and manual solid-phase extraction in terms of repeatability, reproducibility, accuracy and recovery rates for reference and certified materials. Robustness is evaluated on different matrices, such as cow's milk, breast milk and human serum. As a consequence of the reduced number of reusable glassware used, as well as lowering of solvent consumption, recorded blank levels are decreased in favor of limits of detection (LODs). Total analysis time and cost are further reduced using simultaneous sample preparation units and the sample throughput is increased compared to classical methods. As a result, this new approach appears to be suitable for the fast sample preparation often required for such fluids in case of emergency foodstuffs analysis or during large epidemiological studies. (C) 2002 Elsevier Science B.V. All rights reserved. [less ▲]

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