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See detailModified Cap Group Suberoylanilide Hydroxamic Acid Histone Deacetylase Inhibitor Derivatives Reveal Improved Selective Antileukemic Activity
Chanaz, Salmi-Smail; Fabre, Aurélie; Dequiedt, Franck ULg et al

in Journal of Medicinal Chemistry (2010), 53(8)

A series of SAHA cap derivatives was designed and prepared in good-to-excellent yields that varied from 49% to 95%. These derivatives were evaluated for their antiproliferative activity in several human ... [more ▼]

A series of SAHA cap derivatives was designed and prepared in good-to-excellent yields that varied from 49% to 95%. These derivatives were evaluated for their antiproliferative activity in several human cancer cell lines. Antiproliferative activity was observed for concentrations varying from 0.12 to >100 microM, and a molecular modeling approach of selected SAHA derivatives, based on available structural information of human HDAC8 in complex with SAHA, was performed. Strikingly, two compounds displayed up to 10-fold improved antileukemic activity with respect to SAHA; however, these compounds displayed antiproliferative activity similar to SAHA when assayed against solid tumor-derived cell lines. A 10-fold improvement in the leukemic vs peripheral blood mononuclear cell therapeutic ratio, with no evident in vivo toxicity toward blood cells, was also observed. The herein-described compounds and method of synthesis will provide invaluable tools to investigate the molecular mechanism responsible for the reported selectively improved antileukemic activity. [less ▲]

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See detailA modified DOI-based method to statistically estimate the depth of investigation of dc resistivity surveys
Deceuster, J.; Etienne, A.; Robert, Tanguy et al

in Journal of Applied Geophysics (2014), 103

Several techniques are available to estimate the depth of investigation or to identify possible artifacts in dc resistivity surveys. Commonly, the depth of investigation (DOI) is mainly estimated by using ... [more ▼]

Several techniques are available to estimate the depth of investigation or to identify possible artifacts in dc resistivity surveys. Commonly, the depth of investigation (DOI) is mainly estimated by using an arbitrarily chosen cut-off value on a selected indicator (resolution, sensitivity or DOI index). Ranges of cut-off values are recommended in the literature for the different indicators. However, small changes in threshold values may induce strong variations in the estimated depths of investigation. To overcome this problem, we developed a new statistical method to estimate the DOI of dc resistivity surveys based on a modified DOI index approach. This method is composed of 5 successive steps. First, two inversions are performed by using different resistivity reference models for the inversion (0.1 and 10 times the arithmetic mean of the logarithm of the observed apparent resistivity values). Inversion models are extended to the edges of the survey line and to a depth range of three times the pseudodepth of investigation of the largest array spacing used. In step 2, we compute the histogram of a newly defined scaled DOI index. Step 3 consists of the fitting of the mixture of two Gaussian distributions (G1 and G2) to the cumulative distribution function of the scaled DOI index values. Based on this fitting, step 4 focuses on the computation of an interpretation index (II) defined for every cell j of the model as the relative probability density that the cell j belongs to G1, which describes the Gaussian distribution of the cells with a scaled DOI index close to 0.0. In step 5, a new inversion is performed by using a third resistivity reference model (the arithmetic mean of the logarithm of the observed apparent resistivity values). The final electrical resistivity image is produced by using II as alpha blending values allowing the visual discrimination between well-constrained areas and poorly-constrained cells. The efficiency of the proposed methodology is assessed on synthetic and field data. By using synthetic benchmark analysis, we demonstrate that the selected well-constrained cells are well-reconstructed in size and shape as well as in resistivity contrasts. Compared to the existing image appraisal tools, the proposed statistical method allows the identification of the statistically well-constrained cells of the model without using any arbitrary cut-off value. Using this statistical method in combination with the resolution, when interpreting dc resistivity surveys, provides the geophysicist valuable information to avoid over- or misinterpretation of ERT images. [less ▲]

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See detailA modified economic-statistical design of the T2 control chart with variable sample sizes and control limits
Seif, A.; Faraz, Alireza ULg; Heuchenne, Cédric ULg et al

in Journal of Applied Statistics (2011), 38(11), 2459-2469

Recent studies have shown that using variable sampling size and control limits (VSSC) schemes result in charts with more statistical power than variable sampling size (VSS) when detecting small to ... [more ▼]

Recent studies have shown that using variable sampling size and control limits (VSSC) schemes result in charts with more statistical power than variable sampling size (VSS) when detecting small to moderate shifts in the process mean vector. This paper presents an economic-statistical design (ESD) of the VSSC T2 control chart using the general model of Lorenzen and Vance [22]. The genetic algorithm approach is then employed to search for the optimal values of the six test parameters of the chart. We then compare the expected cost per unit of time of the optimally designed VSSC chart with optimally designed VSS and FRS (fixed ratio sampling) T2 charts as well as MEWMA charts. [less ▲]

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See detailA modified economic-statistical design of the VP multivariate control charts
SEIF, Asghar; Faraz, Alireza ULg

Scientific conference (2012, January 15)

Hotelling’s T2 control chart is one of the most popular multivariate control charts for monitoring multiple variables simultaneously. Recent studies have shown that applying the T2 control chart by using ... [more ▼]

Hotelling’s T2 control chart is one of the most popular multivariate control charts for monitoring multiple variables simultaneously. Recent studies have shown that applying the T2 control chart by using a variable parameters (VP) scheme yields more rapid detection of assignable causes than the classical method of taking fixed sample sizes at fixed intervals of time. This paper presents an economic-statistical design (ESD) of the VP T2 control chart using the general model of Lorenzen and Vance. The genetic algorithm (GA) is then employed to search for the optimal values of the eight test parameters of the chart. Furthermore, VP and FRS schemes are compared with respect to the expect cost per unit time. [less ▲]

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See detailModified glucagon test allowing simultaneous estimation of insulin secretion and insulin sensitivity: application to obesity, insulin-dependent diabetes mellitus, and noninsulin-dependent diabetes mellitus.
Castillo, M. J.; Scheen, André ULg; Lefebvre, Pierre ULg

in Journal of Clinical Endocrinology and Metabolism (1995), 80(2), 393-9

The aim of this study was to describe an adaptation of the glucagon test allowing the simultaneous characterization of insulin secretion and sensitivity. A glucagon test (1 mg/m2) was performed in healthy ... [more ▼]

The aim of this study was to describe an adaptation of the glucagon test allowing the simultaneous characterization of insulin secretion and sensitivity. A glucagon test (1 mg/m2) was performed in healthy subjects (n = 11), obese patients (n = 5), insulin-dependent diabetics (n = 9), nonobese noninsulin-dependent diabetics (n = 7), and overweight noninsulin-dependent diabetics (n = 8). Previously, they had been connected to the Biostator, modified for continuous blood collection. Endogenous insulin secretion induced by glucagon was derived from integrated C-peptide concentrations. An index of insulin sensitivity was obtained by dividing the rate of decrease in blood glucose by the total amount of insulin entering the circulation (secreted+infused by the Biostator). The indices of insulin sensitivity obtained in the above groups of subjects were, respectively, 0.064 +/- 0.006, 0.030 +/- 0.006, 0.037 +/- 0.007, 0.021 +/- 0.006, and 0.016 +/- 0.002 mmol/L.U.min (P < 0.001). The estimated insulin secretion values in the 20 min following glucagon injection were, respectively, 0.38 +/- 0.05, 0.65 +/- 0.08, 0.05 +/- 0.01, 0.26 +/- 0.15, and 0.30 +/- 0.07 U (P < 0.001). The insulin sensitivity index obtained from this test correlated with the glucose MCR obtained from a euglycemic glucose clamp (r = 0.816; P < 0.001; n = 12). C-Peptide levels after glucagon administration were also significantly correlated with the estimated endogenous insulin secretion (r = 0.808; P < 0.001; n = 30). This adaptation of the classical glucagon test is an efficient and simple method to simultaneously evaluate insulin secretion and insulin sensitivity. [less ▲]

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See detailModified hormonal balance in rooting-recalcitrant rac mutant tobacco shoots
Faivre-Rampant, Odile; Kevers, Claire ULg; Dommes, Jacques ULg et al

in Plant Biosystems (2001), 135(1), 85-93

The rooting-recalcitrant rac tobacco mutant has been multiplied in vitro via outgrowth of axillary buds in parallel to the DS wild-type. The mutant shoots grew at a lower rate and did not root whatever ... [more ▼]

The rooting-recalcitrant rac tobacco mutant has been multiplied in vitro via outgrowth of axillary buds in parallel to the DS wild-type. The mutant shoots grew at a lower rate and did not root whatever the treatments, whereas the wild-type shoots rooted spontaneously during the culture cycle without auxin treatment. The mutant and wild-type shoots showed similar peroxidase variations along the culture cycle (21 days) but with higher levels of activity for the rac mutant: minimum peroxidase activity occurrey at day 14 in whole shoots of both tobacco genotypes, but already at day 7 in the basal parts of the stems (where roots appear) of the wild-type tobacco, while it was delayed in the mutant. Free and conjugated auxin and polyamine levels were also determined in whole shoots and basal parts of the stems. The rac mutant was characterised by higher auxin and polyamine contents. A peak of auxins and polyamines appeared at day 14 in the whole shoots whatever the tobacco genotype. This peak was delayed in the basal parts of the rac stems compared to the wild-type ones. The mutant shoots contained higher levels of benzyladenine and isopentenyladenosine at the end of the culture cycle, whereas zeatin riboside was more abundant in wild-type shoots. In response to increasing concentrations of indole-3-butyric acid (IBA) and 1-naphthaleneacetic acid (NAA), only the wild-type shoots responded by an increase in growth rate followed by inhibition at high concentrations. The rac shoot responses were very low or nonexistent. Peroxidase activity was also measured in E basal parts of tobacco stems grown in the presence of IBA. Results suggest growth inhibition related to auxin accumulation, possibly combined with elevated putrescine content. Second, rooting induction seems to take place in both tobacco genotypes; however, the process of root formation is blocked in the mutant. The lack of initiation and expression phases of rooting in relation to auxin content in the mutant is discussed. [less ▲]

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See detailModified human growth hormone
Martial, Joseph ULg; Lecomte, Corine

Patent (1990)

Protein derived from human growth hormone (hGH), which no longer has the first two amino acids of the natural hypophysial hormone at the terminal end of the amino acid, retaining its main biological ... [more ▼]

Protein derived from human growth hormone (hGH), which no longer has the first two amino acids of the natural hypophysial hormone at the terminal end of the amino acid, retaining its main biological activity of bone and somatic growth stimulation, but no longer having the transitory and diabetogenic insulin effects generally observed when administering hGH. Said modified growth hormone protein can be used for therapeutic purposes, in particuliar for treating clinical cases where the effects of the growth hormone sugars on the metabolism are to be avoided: patients suffering from cachexia, new-born babies and the elederly. [less ▲]

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See detailA modified item response model to detect and correct for cheating
Magis, David ULg; Raîche, Gilles

Conference (2011, October 13)

This talk focuses on the identification of respondents with cheating behaviour to educational or psychometric tests. Cheating behaviour is often observed when some examinee with low ability level, tries ... [more ▼]

This talk focuses on the identification of respondents with cheating behaviour to educational or psychometric tests. Cheating behaviour is often observed when some examinee with low ability level, tries to get correct responses (in some way or another) to get higher grades. This results usually in a response pattern that does not fit the underlying item response theory (IRT) model and severely affects the estimation of ability level. Until now, several indices of misfit have been proposed, and they seem accurate for detecting cheating (as well as other misfitting behaviours). Unfortunately, none of these indexes permit: (a) to determine which type of behaviour is encountered, and (b) to propose a corrected estimation of the examinee’s ability level. The purpose of this talk is to present Raîche’s multidimensional model as an extension of the usual IRT models but incorporating additional person parameters to characterize misfitting behaviour. Emphasis is put on a simple model with personal pseudo-guessing variation to detect trends in cheating. Results from a simulation study indicate that, in the absence of cheating, the multidimensional model returns similar estimates than the traditional IRT models, while in the presence of cheating, the person pseudo-guessing parameter is an accurate index of misfit and the person ability estimates are less biased than its traditional counterpart. [less ▲]

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See detailModified Non-Ionic Solid Supports: a Way to High Activity Fluorine-18 Radiochemistry in Microfluidic Devices
Aerts, Joël ULg; Voccia, Samuel; Lemaire, Christian ULg et al

in Journal of Labelled Compounds & Radiopharmaceuticals (2009, July), 52(S1), 12

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See detailThe modified Reyment's multivariate coefficient of variation
Zhang, Lixin ULg

Conference (2010, May 18)

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See detailA modified surgical model of fulminant hepatic failure in the rat.
DETRY, Olivier ULg; Gaspar, Yves; CHERAMY-BIEN, Jean-Paul ULg et al

in Journal of Surgical Research (2013), 181

BACKGROUND: There is a need for better animal models of fulminant liver failure (FHF). Eguchi et al described an interesting surgical model of FHF in the rat. This model includes 68% partial hepatectomy ... [more ▼]

BACKGROUND: There is a need for better animal models of fulminant liver failure (FHF). Eguchi et al described an interesting surgical model of FHF in the rat. This model includes 68% partial hepatectomy, ischemia of 24% of the liver mass, and 8% of remnant liver left intact. In the original description by Eguchi et al, rats were administered subcutaneous glucose. However, the authors found that normothermic FHF rats with subcutaneous glucose died from deep hypoglycemia. In this report, we describe a modification of that model, and show that administration of intravenous glucose allows better survival and development of intracranial hypertension. METHODS: We operated on FHF rats using the procedure described by Eguchi et al, kept them normothermic, and maintained normoglycemia by continuous intravenous glucose injection (glucose 10%, 1 mL/h). At 24 h, we monitored liver blood tests (n = 5), intracranial pressure (n = 5), clinical encephalopathy, and survival (n = 10), and compared them with sham and 68% hepatectomy rats. RESULTS: The FHF rats developed acute cytolysis, cholestasis, and liver failure, as demonstrated by the liver blood tests. They experienced progressive encephalopathy and intracranial hypertension leading to death. Mean survival was 45.9 h. Of 10 FHF rats from the survival evaluation cohort, one survived 7 d. Laparotomy showed necrosis of lateral liver lobes and enlargement of omental lobes with a normal hepatic aspect, suggesting liver recovery. CONCLUSIONS: This surgical rat model mimics the features of human FHF and seems interesting for further research into the pathophysiology and therapeutic management of the disease. [less ▲]

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See detailA Modified Tetris Model Including The Effect of Friction
Ludewig, François ULg; Dorbolo, Stéphane ULg; Caps, Hervé ULg et al

in Traffic and Granular Flow'03 (2003)

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See detailModified TiO2-based Photocatalytic Films and Powders produced by Aqueous and Non-Aqueous Sol-Gel Processes for Water Purification
Malengreaux, Charline ULg

Doctoral thesis (2013)

Summary Two major research goals have been proposed for this thesis. The first goal concerns the development of photocatalysts in the shape of thin films coated on glass substrates which includes (i) the ... [more ▼]

Summary Two major research goals have been proposed for this thesis. The first goal concerns the development of photocatalysts in the shape of thin films coated on glass substrates which includes (i) the development of a sol-gel chemistry suitable for the production of stable colloidal suspensions of TiO2 particles, (ii) the optimization of the deposition method and (iii) the development of an experimental device to measure the photocatalytic activity of the films. The second objective is the development of innovative non-aqueous and aqueous sol-gel routes, including the development of new methods for the introduction of dopants as well as the photocatalytic testing of the resulting materials. Two original non-aqueous sol-gel processes involving respectively, an in situ production of water and the controlled addition of a small amount of water, have been developed to produce a series of stable colloidal suspensions of TiO2 particles (sols). From those sols, transparent, adherent, homogeneous thin films have been produced using an optimized dip-coating deposition method and have been proven to be photocatalytically active for the degradation of an organic pollutant in aqueous solution. The photocatalytic activity of the films has been improved through an increase of their roughness thanks to the addition of an organic additive into the sol, leading to an increased active surface involved into the photocatalytic reaction. A mathematical model allowing the rigorous evaluation of the kinetic parameters of the photocatalytic reaction taking into account the influence of the variation of the volume inside the batch photoreactor has been developed. The equations have been established in the case of a photocatalytic powder homogeneously dispersed in the pollutant solution, and in the case of a photocatalytic thin film placed at the bottom of the reactor. The particular case of a first order reaction has been treated and the error on the reaction rate constant induced by neglecting the volume variation has been quantified. An environmentally-friendly aqueous sol-gel process for producing undoped and Cu2+, Ni2+, Zn2+, Pb2+, Fe3+, Cr3+, La3+ or Eu3+ single-doped as well as La3+- Fe3+ and Eu3+- Fe3+ co-doped TiO2 bulk photocatalysts composed of nanocrystallites of anatase and exhibiting a remarkably high photocatalytic activity without requiring any calcination step has been developed. Different effects of the metal ion dopant on the photocatalytic activity have been observed and discussed according to the dopant nature and content. A kinetic study of the photocatalytic degradation of a model pollutant (4-nitrophenol) in aqueous solution under UV-Visible light (330 nm < λ < 800 nm) has been performed over a promising TiO2-Zn2+ doped catalyst. Statistical validations have confirmed the suitability of the phenomenological reaction rate model developed to represent the 4-nitrophenol photocatalytic degradation over time. [less ▲]

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See detailA modified TVD scheme for the advection of two or more variables with consideration for their sum
Mercier, Christophe ULg; Delhez, Eric ULg

in Ocean Dynamics (2010), 60

Total variation diminishing (TVD) advection schemes are known to produce results that are free from some of the numerical artifacts (no overshooting, no spurious oscillation, small diffusion) that can ... [more ▼]

Total variation diminishing (TVD) advection schemes are known to produce results that are free from some of the numerical artifacts (no overshooting, no spurious oscillation, small diffusion) that can spoil the physical significance of the results. When two or more tracers are advected separately using a TVD scheme, the sum of these variables can however exhibit some inappropriate behaviors. The total variation of the sum will not necessarily be non- increasing and local artificial oscillations and extrema can appear. We show that these can be avoided with only minor perturbations of the original solution by adjusting the slope limiters used for the different variables. If the sum of these variables has some physical significance, for instance as refinement of a larger model compartment, the correction procedure introduced in this paper should be used to ensure a physically meaningful solution. [less ▲]

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See detailModifier l'utilisation/la destination d'un bâtiment, en Région wallonne
Delnoy, Michel ULg

in Immobilier (1999), 2

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See detailModifier les représentations de l'échec à l'école normale
Beckers, Jacqueline ULg

in Recherche en Education. Théorie & Pratique (1994), 18-19

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See detailModifying eigenvalue interactions near weak resonance
Auvray, Vincent; Dobson, Ian; Wehenkel, Louis ULg

in Proc. of International Symposium on Circuits and Systems (2004)

In electric power system instabilities such as subsynchronous resonance or interarea oscillations, two complex modes can approach each other in frequency and then interact by changing damping so that one ... [more ▼]

In electric power system instabilities such as subsynchronous resonance or interarea oscillations, two complex modes can approach each other in frequency and then interact by changing damping so that one of the modes becomes unstable. Selecting changes in parameters to minimize this interaction is difficult by trial and error. By analyzing the interaction as a perturbation of a weak resonance, we calculate sensitivities that indicate the parameters to be changed to minimize the interaction and stabilize the system. The method is illustrated with a simple example of two coupled linear oscillators. The use of sensitivity methods to change the type of the interaction is also demonstrated. [less ▲]

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See detailUn modo attutito d’esistere: Note su Sbarbaro traduttore dal francese
Benzoni, Pietro ULg

in Ferreri, Davide (Ed.) Camillo Sbarbaro in versi e in prosa (2009)

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See detailA modular approach to quality of life assessment in paediatric oncology
Fonseca, Marta; Missotten, Pierre ULg; Etienne, Anne-Marie ULg et al

in Psychology & Health (2009), 24(Supp 1), 175

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