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See detailDisease Modifying drugs for OA: from research to clinical evidences
Henrotin, Yves ULg

Conference (2014, April 24)

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See detailDisease severity assessment in epidemiological studies: accuracy and reliability of visual estimates of Septoria leaf blotch (SLB) in winter wheat.
El Jarroudi, Moussa ULg; Kouadio, Louis; Mackels, Christophe et al

in Phytopathology (2014), 104(11), 37

The accuracy and reliability of visual assessments of SLB severity by raters (i.e. one plant pathologist with extensive experience and three other raters trained prior to field observations using standard ... [more ▼]

The accuracy and reliability of visual assessments of SLB severity by raters (i.e. one plant pathologist with extensive experience and three other raters trained prior to field observations using standard area diagrams and DISTRAIN) was determined by comparison with assumed actual values obtained by digital image analysis. Initially analyses were performed using SLB severity over the full 0-100% range; then, to explore error over short ranges of the 0-100% scale, the scale was divided into sequential 10%-increments based on the actual values. Lin’s concordance correlation (LCC) analysis demonstrated that all raters were accurate when compared over the whole severity range (LCC coefficient (ρc)= 0.92-0.99). However, agreement between actual and visual SLB severities was less good when compared over the short intervals of the 10×10% classes (ρc= -0.12-0.99), demonstrating that agreement will vary depending on the actual disease range over which it is compared. Inter-rater reliability between each pair of raters over the full 0-100% range (correlation analysis r= 0.970-0.992, P<0.0001), and inter-class correlation coefficient (ρ≥ 0.927) were very high. This study provides new insight into using a full range of actual disease severity vs limited ranges to ensure a realistic measure of rater accuracy and reliability, in addition to contributing to the ongoing debate on the use of visual disease estimates based on the 0-100% ratio scale for epidemiological research. [less ▲]

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See detailDisease Severity Estimates – Effects of Rater Accuracy and Assessment Methods for Comparing Treatments
Bock, Clive; El Jarroudi, Moussa ULg; Kouadio, Louis et al

in Plant Disease (2015), 99(1104-1112),

Assessment of disease severity is required for several purposes in plant pathology; most often the estimates are made visually. It is established that visual estimates can be inaccurate and unreliable ... [more ▼]

Assessment of disease severity is required for several purposes in plant pathology; most often the estimates are made visually. It is established that visual estimates can be inaccurate and unreliable. The ramifications of biased or imprecise estimates by raters have not been fully explored using empirical data; partly because of the logistical difficulties involved in different raters assessing the same leaves for which actual disease has been measured in a replicated experiment with multiple treatments. In this study nearest percent estimates (NPEs) of Septoria leaf blotch (SLB) on leaves of winter wheat from non-treated and fungicide treated plots were assessed in both 2006 and 2007 by four raters and compared to assumed true values measured using image analysis. Lin’s concordance correlation (LCC, ρc) was used to assess agreement between the two approaches. NPEs were converted to Horsfall-Barratt (HB) mid-points and again compared for agreement with true values. The estimates of SLB severity from fungicide-treated and non-treated plots were analyzed using generalized linear mixed modeling to ascertain effects of rater using both the NPE and HB values. Rater 1 showed good agreement with image analysis (ρc = 0.986 to 0.999), while raters 3 and 4 had less good agreement (ρc = 0.205 to 0.936). Conversion to the HB scale had little effect on bias or accuracy, but reduced both precision and agreement for most raters on most assessment dates (precision, r = -0.001 to -0.132; and agreement, ρc = -0.003 to -0.468). Inter-rater reliability was also reduced slightly by conversion of estimates to HB midpoint values. Estimates of mean SLB severity were significantly different between image analysis and raters 2, 3 and 4, and there were frequently significant differences among raters (F=151 to 1260, P=0.001 to <0.0001). Conversion to the HB scale changed the means separation ranking of rater estimates on 26 June 2007. Nonetheless, image analysis and all raters were able to differentiate control and treated plots treatments (F=116 to 1952, P=0.002 to <0.0001, depending on date and rater). Conversion of NPEs to the HB scale tended to reduce F-values slightly (2006: NPEs, F=116 to 276, P=0.002 to 0.0005, and for the HB converted values F=101 to 270, P=0.002 to 0.0005, and in 2007, NPEs, F=164 to 1952 P=0.001 to <0.0001, and for HB converted values F=126 to 1633 P=0.002 to <0.0001). The results demonstrated the need for accurate and reliable disease assessment to minimize over or underestimates compared to actual disease, and where multiple raters are deployed, they should be assigned in a manner to reduce any potential effect of rater differences on the analysis. [less ▲]

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See detailDisease-related amyloidogenic variants of human lysozyme trigger the unfolded protein response and disturb eye development in Drosophila melanogaster
Kumita, Janet R.; Helmfors, Linda; Williams, Jocy et al

in FASEB Journal (2012)

We have created a Drosophila model of lysozyme amyloidosis to investigate the in vivo behavior of disease-associated variants. To achieve this objective, wild-type (WT) protein and the amyloidogenic ... [more ▼]

We have created a Drosophila model of lysozyme amyloidosis to investigate the in vivo behavior of disease-associated variants. To achieve this objective, wild-type (WT) protein and the amyloidogenic variants F57I and D67H were expressed in Drosophila melanogaster using the UAS-gal4 system and both the ubiquitous and retinal expression drivers Act5C-gal4 and gmr-gal4. The nontransgenic w(1118) Drosophila line was used as a control throughout. We utilized ELISA experiments to probe lysozyme protein levels, scanning electron microscopy for eye phenotype classification, and immunohistochemistry to detect the unfolded protein response (UPR) activation. We observed that expressing the destabilized F57I and D67H lysozymes triggers UPR activation, resulting in degradation of these variants, whereas the WT lysozyme is secreted into the fly hemolymph. Indeed, the level of WT was up to 17 times more abundant than the variant proteins. In addition, the F57I variant gave rise to a significant disruption of the eye development, and this correlated to pronounced UPR activation. These results support the concept that the onset of familial amyloid disease is linked to an inability of the UPR to degrade completely the amyloidogenic lysozymes prior to secretion, resulting in secretion of these destabilized variants, thereby leading to deposition and associated organ damage.-Kumita, J. R., Helmfors, L., Williams, J., Luheshi, L. M., Menzer, L., Dumoulin, M., Lomas, D. A., Crowther, D. C., Dobson, C. M., Brorsson, A.-C. Disease-related amyloidogenic variants of human lysozyme trigger the unfolded protein response and disturb eye development in Drosophila melanogaster. [less ▲]

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See detailDiseases of pigeons
Marlier, Didier ULg; Vindevogel, Henri ULg

in Brugère-Picoux, Jeanne; Vaillancourt, Jean-Pierre; Bouzouaia, Moncef (Eds.) et al Manual of Poultry Diseases (2015)

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See detailDiselenide Derivative, Potential Successor of Ebselen with High Antioxidant Activity: Assessment on in vitro Models
Mareque-Faez, Juan; Deby, Carol; Lamy, Maurice ULg et al

in Resource-Full Chemistry (2008, May 24)

Oxidative stress plays a key role in several pathophysiological events, including the attack of DNA, cell membrane damage and signaling pathways disruption. The harmful effect of oxidant stress has been ... [more ▼]

Oxidative stress plays a key role in several pathophysiological events, including the attack of DNA, cell membrane damage and signaling pathways disruption. The harmful effect of oxidant stress has been attributed to a high production of reactive oxygen species (ROS) followed by a depletion of antioxidant enzymes, glutathione peroxidase (GPx), a mammalian selenoenzyme which functions as a catalytic antioxidant, has been described to protect various organisms against oxidative stress. In the past two decades, the design of small weight molecules such as ebselen (PZ 51, 2-phenyl-1,2-benzoisoselenazol-3(2H)-one), has renewed the interest of synthetic analogues able to mimic the GPx activity. From four in vitro in vitro models, we previously showed that ebselen and some of its analogues (compounds 1, 2, 3 and 4) not only behaved at various degrees as GPx-like mimics but also as antioxidants especially for diselenide derivative (3). The present study deals with the antioxidant effect of diselenide derivative (3) versus ebselen on cellular model and the enzyme myeloperoxidase (MPO) activity using the in vitro systems. Derivative (3) has been chosen because of its interesting antioxidant profile in cell-free systems. [less ▲]

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See detailDisentanglement of magnetic field mixing reveals the spontaneous M2 decay rate for a metastable level in Xe+
Schef, P.; Lundin, P.; Biémont, Emile ULg et al

in Physical Review A (2005), 72(2),

We have investigated the radiative decay of the metastable level 5d(4)D(7/2) in Xe+. Theoretically we find the decay to be heavily dominated by an M2 transition and not by M1/E2 transitions. Lifetime ... [more ▼]

We have investigated the radiative decay of the metastable level 5d(4)D(7/2) in Xe+. Theoretically we find the decay to be heavily dominated by an M2 transition and not by M1/E2 transitions. Lifetime measurements of 5d(4)D(7/2) in a storage ring are difficult since magnetic mixing of the metastable with a short-lived level quenches its population. Decay rates were determined at different magnetic field strengths (B) in order to allow a nonlinear extrapolation to B=0. The experimental lifetime of 2.4 +/- 0.8 s was in agreement with the calculated value, but much smaller than previously estimated. [less ▲]

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See detailDisentangling component spectra of κ Scorpii, a spectroscopic binary with a pulsating primary. II. Interpretation of the line-profile variability
Uytterhoeven, K.; Briquet, Maryline ULg; Aerts, C. et al

in Astronomy and Astrophysics (2005), 432

We analyse the complex short-term SiIII line-profile variability of the spectroscopic binary β Cep star κ Scorpii after orbit subtraction, before and after spectral disentangling. We refine the known ... [more ▼]

We analyse the complex short-term SiIII line-profile variability of the spectroscopic binary β Cep star κ Scorpii after orbit subtraction, before and after spectral disentangling. We refine the known oscillation frequency of the star: f[SUB]1[/SUB]=4.99922 c d[SUP]-1[/SUP] and detect 2f[SUB]1[/SUB]. Variability is also found at frequencies near f[SUB]2[/SUB]≃ 4.85 c d[SUP]-1[/SUP] and f[SUB]3[/SUB]≃ 5.69 c d[SUP]-1[/SUP] or their aliases. These frequencies are not significant if we consider the spectra alone, but they survive our selection after the consideration that they were derived previously from independent ground-based and space photometry by different teams. Moreover, we find dominant variability in the equivalent width with a frequency in the interval [0.22,0.30] c d[SUP]-1[/SUP] which we interpret as the rotational frequency f[SUB]rot[/SUB] of the star. The complex window function does not allow us to determine definite values for f[SUB]2[/SUB], f[SUB]3[/SUB], f[SUB]rot[/SUB]. The variability with f[SUB]1[/SUB] is interpreted as a prograde non-radial oscillation mode with spherical wavenumbers (ℓ,m)=(2,-1) or (1,-1). The additional frequencies are explained in terms of rotational modulation superposed to the main oscillation. We also point out that we cannot disprove the variability in κ Scorpii to originate from co-rotating structures. KOREL disentangling preserves the large-amplitude line-profile variability but its performance for complex low-amplitude variability remains to be studied in detail. Based on observations obtained with the Coudé Échelle Spectrograph on the ESO CAT telescope and with the CORALIE échelle spectrograph on the 1.2-m Euler Swiss telescope, both situated at La Silla, Chile. [less ▲]

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See detailDisentangling planetary orbits from stellar activity in radial-velocity surveys
Haywood, R. D.; Cameron, A. Collier; Queloz, D. et al

in International Journal of Astrobiology (2014), 13

The majority of extra-solar planets have been discovered (or confirmed after follow-up) through radial-velocity (RV) surveys. Using ground-based spectrographs such as High Accuracy Radial Velocity ... [more ▼]

The majority of extra-solar planets have been discovered (or confirmed after follow-up) through radial-velocity (RV) surveys. Using ground-based spectrographs such as High Accuracy Radial Velocity Planetary Search (HARPS) and HARPS-North, it is now possible to detect planets that are only a few times the mass of the Earth. However, the presence of dark spots on the stellar surface produces RV signals that are very similar in amplitude to those caused by orbiting low-mass planets. Disentangling these signals has thus become the biggest challenge in the detection of Earth-mass planets using RV surveys. To do so, we use the star's lightcurve to model the RV variations produced by spots. Here we present this method and show the results of its application to CoRoT-7. [less ▲]

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See detailDisentangling temporal patterns in our perception of the fossil history of gymnosperms
Cascales - Miñana, Borja ULg

in Historical Biology (2012), 24(2), 143-159

By taking gymnosperms as a case study, this article evaluates the perception of plant life history from the fossil record to test the biases associated with the time-dependent aspects of the taxonomy ... [more ▼]

By taking gymnosperms as a case study, this article evaluates the perception of plant life history from the fossil record to test the biases associated with the time-dependent aspects of the taxonomy, following a stepwise modelling procedure based on two divergent sets of time units. The idea that the effects of the temporal component of paleobiological inference need to be evaluated to remove any possible bias in our interpretation and perception of plant evolution based on analyses of large-scale data sets is investigated. The results reveal important differences in our perception of the tempo of gymnosperm evolution and how it is biased in terms of time unit length due to the loss of information as a consequence of the timescale resolution. Despite singletons representing real morphological diversity translated into independent taxonomic categories, these taxa can distort perceptions of the intensity of the long paleofloristic diversification moments of gymnosperms if their effect is not considered. This study shows a complete overview of the evolutionary profiles of gymnosperms with significant discrepancies in the function of how singletons are quantitatively processed in paleobotanical data analyses, and it provides new evidence about how the 'zoom effect' can magnify our perception of extinction events. © 2012 Copyright Taylor and Francis Group, LLC. [less ▲]

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See detailDisentangling the sources of phenotypic variation in Ambrosia artemisiifolia L.: the role of seed traits
Ortmans, William ULg; Monty, Arnaud ULg; Mahy, Grégory ULg

Poster (2014, November 03)

When invading new environments, a plant invader may express new phenotypes as a result of different ecological and genetic processes. It includes phenotypic plasticity, local adaptation, environmental ... [more ▼]

When invading new environments, a plant invader may express new phenotypes as a result of different ecological and genetic processes. It includes phenotypic plasticity, local adaptation, environmental maternal effects, and genetic drift. The quantification of each of these factors is crucial in the study of biological invasions. Ambrosia artemisiifolia L. invasion success is strongly linked to seed characteristics (dispersal by human activities, long-lived soil seed bank, etc.). Known as an opportunist and a colonizer, the species is often limited by the competition from other plants. In the early stages of development, the seedlings can be quickly outcompeted and a rapid growth is therefore a major advantage. First, this study aims to analyze the seed traits variation, and to detect an impact of these traits on the early development of the seedling (environmental maternal effect). Second, we aimed to quantify the respective role of phenotypic plasticity, environmental maternal effect, local adaptation and genetic drift on seedlings phenotype. Variability of seeds from 3 geographical zones (Belgium – Centre of France – South of France) was assessed. We measured the seed variation in mass, length, width, circularity, and pigmentation. Seeds were disposed in growth chamber under two temperature treatments. After two months, we compared seedling phenotypic variation in germination time, height, aboveground biomass, belowground biomass, early competitive performance, and the final leaf area. We found a high variability of seed traits. Seeds were varying significantly among zones, populations, and parents, with more than 30% of the variation attributable to the mother plant identity. The main sources of seedling phenotypic variation appeared to be phenotypic plasticity and environmental maternal effect. No genetic differentiation was detected in this study. Seed mass was positively correlated to seedling biomass, early competitive performance, and the final leaf area. The relevance of traits reflecting environmental maternal effect is discussed. Phenotypic plasticity and seed characteristics appear to play a major role in the invasion success. [less ▲]

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See detailDisfuncion ventricular en la infeccion HIV perinatal
Valdes, Eduardo F; Fernandez Rostello, Eduardo; Romero Villanueva, Horacio et al

in Prensa Medica Argentina (1995), 82

We studied cardiovascular function in four babies . There were three females (3, 6 and 9 months old ) and one 6 months old male with HIV perinatal infection (ELISA and Western blot positives). CD4 counts ... [more ▼]

We studied cardiovascular function in four babies . There were three females (3, 6 and 9 months old ) and one 6 months old male with HIV perinatal infection (ELISA and Western blot positives). CD4 counts were: 1150/mm3, 1250 /mm3, 950/mm3 and 1066/mm3 respectively. The first baby had pneumocystosis and oral candidiasis, and two other had bacterial pneumonia and viral brochiolitis as antecedents. We observed after echocardiographic Doppler evaluation right ventricle diastolic dysfunction in three cases. Interestingly there were no pulmonary hypertension. Diastolic and systolic left ventricle function was normal in all babies. Our previous results in 27 AIDS adult patients let us to identify mainly left ventricle dysfunction (Valdes E & al Prensa Medica Argentina 1994). On the contrary, right ventricle dysfunction was predominant in this small series. Lipshultz & al (Am J Cardio 1990) found in 31 perinatal AIDS ventricular dysfunction, myocardial dilatation, arrhythmias and pericardial effusion. Our results combined with a literature review point out cardiac dysfunction as a frequent finding in children with AIDS. As these alterations are not necessarily clinically apparent, we recommend routine echocardiographic evaluation in these patients. Physiopathological clues in AIDS cardiac dysfunction remain elusive: HIV cytotoxic myocardiopathy, opportunistic infections and/or viral autoimmune mechanisms have been considered as potential causes. [less ▲]

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See detailDisinfectant choices in veterinary practices, shelters and households : ABCD guidelines on safe and effective disinfection for feline environments
Addie, D.D.; Boucraut-Baralon, C.; Egberink, H. et al

in Journal of Feline Medicine and Surgery (2015), 17

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See detailDiskrete Modellierung - ein statistischer Ansatz zur detaillierten Beschreibung molekularer Zustände
Wallek, T; Pfleger, M; Pfennig, Andreas ULg

Conference (2013)

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See detailDiskrete Modellierung kondensierter Phasen
Wallek, T; Pfleger, M; König, L M et al

Conference (2013)

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See detailLa dislocation du secteur minier au Katanga (RDC). Pillage ou recomposition?
Rubbers, Benjamin ULg

in Politique Africaine (Paris, France : 1981) (2004), 93

New actors appeared in the mining sector of Katanga, formerly the monopoly of a public corporation, and transformed its relationship to the state and the global economy. By contrast with a legalist ... [more ▼]

New actors appeared in the mining sector of Katanga, formerly the monopoly of a public corporation, and transformed its relationship to the state and the global economy. By contrast with a legalist approach, this article tries to better understand their role in the future of Katanga by following their career in the recent history of the region. [less ▲]

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