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See detailRealisation of a fully-deterministic microlensing observing strategy for inferring planet populations
Dominik, M.; Jørgensen, U. G.; Rattenbury, N. J. et al

in Astronomische Nachrichten (2010), 331

Within less than 15 years, the count of known planets orbiting stars other than the Sun has risen from none to more than 400 with detections arising from four successfully applied techniques: Doppler ... [more ▼]

Within less than 15 years, the count of known planets orbiting stars other than the Sun has risen from none to more than 400 with detections arising from four successfully applied techniques: Doppler-wobbles, planetary transits, gravitational microlensing, and direct imaging. While the hunt for twin Earths is on, a statistically well-defined sample of the population of planets in all their variety is required for probing models of planet formation and orbital evolution so that the origin of planets that harbour life, like and including ours, can be understood. Given the different characteristics of the detection techniques, a complete picture can only arise from a combination of their respective results. Microlensing observations are well-suited to reveal statistical properties of the population of planets orbiting stars in either the Galactic disk or bulge from microlensing observations, but a mandatory requirement is the adoption of strictly-deterministic criteria for selecting targets and identifying signals. Here, we describe a fully-deterministic strategy realised by means of the ARTEMiS (Automated Robotic Terrestrial Exoplanet Microlensing Search) system at the Danish 1.54-m telescope at ESO La Silla between June and August 2008 as part of the MiNDSTEp (Microlensing Network for the Detection of Small Terrestrial Exoplanets) campaign, making use of immediate feedback on suspected anomalies recognized by the SIGNALMEN anomaly detector. We demonstrate for the first time the feasibility of such an approach, and thereby the readiness for studying planet populations down to Earth mass and even below, with ground-based observations. While the quality of the real-time photometry is a crucial factor on the efficiency of the campaign, an impairment of the target selection by data of bad quality can be successfully avoided. With a smaller slew time, smaller dead time, and higher through-put, modern robotic telescopes could significantly outperform the 1.54-m Danish, whereas lucky-imaging cameras could set new standards for high-precision follow-up monitoring of microlensing events. Based on data collected by the MiNDSTEp consortium with the Danish 1.54-m telescope at the ESO La Silla Observatory. [less ▲]

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See detailHST Observations of Gravitationally Lensed QSOs
Claeskens, Jean-François ULg; Sluse, Dominique ULg; Surdej, Jean ULg

in Macchetto, D. F. (Ed.) The Impact of HST on European Astronomy (2010)

Thanks to its sharp view, HST has significantly improved our knowledge of tens of gravitationally lensed quasars in four different respects: (1) confirming their lensed nature; (2) detecting the lensing ... [more ▼]

Thanks to its sharp view, HST has significantly improved our knowledge of tens of gravitationally lensed quasars in four different respects: (1) confirming their lensed nature; (2) detecting the lensing galaxy responsible for the image splitting; (3) improving the astrometric accuracy on the positions of the unresolved QSO images and of the lens; (4) resolving extended lensed structures from the QSO hosts into faint NIR or optical rings or arcs. These observations have helped to break some degeneracies on the lens potential, to probe the galaxy evolution and to reconstruct the true shape of the QSO host with an increased angular resolution. [less ▲]

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See detailMacaronesia: a source of hidden genetic diversity for post-glacial recolonization of western Europe in the leafy liverwort Radula lindenbergiana.
Laenen, Benjamin ULg; Desamore, Aurélie ULg; Devos, Nicolas et al

Poster (2010)

Aim Bryophytes exhibit the lowest rates of endemism among biota in Macaronesia and differ in diversity patterns from angiosperms by the widespread occurrence of endemics within and among archipelagos. In ... [more ▼]

Aim Bryophytes exhibit the lowest rates of endemism among biota in Macaronesia and differ in diversity patterns from angiosperms by the widespread occurrence of endemics within and among archipelagos. In this study, we test the hypothesis that high dispersal ability erodes phylogeographic signal and hampers the chances of diversification in bryophytes using the leafy liverwort Radula lindenbergiana as a model. Location Macaronesia, Europe, South Africa Methods 84 samples were collected across the species distribution range and sequenced at four cpDNA loci (atpB-rbcL, trnG, trnL, and rps4). Phylogenetic reconstructions and Bayesian ancestral area reconstructions were used in combination with population genetic statistics (H, Nst, Fst) to describe the pattern of present genetic diversity in R. lindenbergiana and infer its biogeographic history. Results The two regions with the highest haplotypic diversity are Madeira and the Canary Islands. Ancestral area reconstructions suggest that Macaronesia was colonized at least twice independently and that the haplotypes currently found in Western Europe share a Macaronesian common ancestor. Whilst analysis of molecular variance and Nst statistics indicate that present-day patterns of genetic variation have a globally significant biogeographic component, Fst values among Macaronesian archipelagos, North Africa, and the Iberian Peninsula, were not significant. Main conclusions The apparent lack of speciation amongst Macaronesian bryophytes hides actual patterns of diversification at the molecular level. The occurrence of Canarian endemic haplotypes across several islands, along with the non-significant Fst and Nst among islands, North Africa and the Iberian Peninsula, suggest intense dispersal. The occurrence of endemic haplotypes suggests, however, that dispersal does not completely prevent diversification. The high diversity found among Macaronesian haplotypes, together with the Macaronesian origin of all the haplotypes found in Western Europe, suggests that Macaronesian archipelagos could have served as a refugium during the Quaternary glaciations and as a source for re-colonization of Europe. [less ▲]

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See detailBiogeography of terrestrial cyanobacteria from Antarctic ice-free areas
Namsaraev, Zorigto ULg; Mano, Marie-José ULg; Fernandez Carazo, Rafael ULg et al

in Annals of Glaciology (2010), 51(56), 171-177

Cyanobacteria inhabit the Antarctic continent and have even been observed in the most southerly ice-free areas of Antarctica (86–878 S). The highest molecular diversity of cyanobacterial communities was ... [more ▼]

Cyanobacteria inhabit the Antarctic continent and have even been observed in the most southerly ice-free areas of Antarctica (86–878 S). The highest molecular diversity of cyanobacterial communities was found in the areas located between 708 S and 808 S. Further south and further north from this zone, the diversity abruptly decreased. Seventy-nine per cent (33 of 42 operational taxonomic units) of Antarctic terrestrial cyanobacteria have a cosmopolitan distribution. Analysis of the sampling efforts shows that only three regions (southern Victoria Land, the Sør Rondane Mountains and Alexander Island) have been particularly well studied, while other areas did not receive enough attention. Although cyanobacteria possess a capacity for long-range transport, regional populations in Antarctic ice-free areas seem to exist. The cyanobacterial communities of the three most intensively studied regions, separated from each other by a distance of 3000–3400 km, had a low degree of similarity with each other. Further development of microbial biogeography demands a standardized approach. For this purpose, as a minimal standard, we suggest using the sequence of cyanobacterial 16S rRNA gene between Escherichia coli positions 405–780. [less ▲]

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See detailPrincipales maladies parasitaires et mycosiques zoonotiques des animaux de compagnie. Partim : Mycoses et parasitoses cutanées
Mignon, Bernard ULg

in Risques zoonosiques liés aux animaux de compagnie (chiens et chats), Proceedings du Symposium de l'AESA (2010)

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See detailPreliminary results obtained by ria determination of the proteins associated to pregnancy (PAG) in goat and sheep
Zamfirescu, S; Nadolu, D; Beckers, Jean-François ULg

in Annals of the Romanian Society for Cell Biology (2010), XV(1), 98-104

In goat and sheep, the glycoproteins associated to pregnancy (PAG) are little studied. Their study in these species is very important in the evaluation of prediction of early pregnancy. Even though ... [more ▼]

In goat and sheep, the glycoproteins associated to pregnancy (PAG) are little studied. Their study in these species is very important in the evaluation of prediction of early pregnancy. Even though numerous research has been done in order to investigate the physiological functions of placental proteins, the exact biofunction of the glycoproteins associated to pregnancy is still unknown. The objective of research was the study of the dynamics of PAG in goats and ewes in the first part of pregnancy(1-35 days after mating) and the determination of correlations with the reproductive status of females and to earlier the pregnancy.The experiment was realized on 49 Saanen x Carpatina goats and 72 Merinos of Palas sheep from the biostation of the Research and Development Institute for Goat and Sheep, Palas Constanta. The females in normal reproduction season were monitored for the detection of estrus and mated naturally. The blood was collected by puncture of the jugular vein on days 0, 7, 14, 25 and 35 after mating (day 0). The serum was obtained after centrifuging at 1500 x g for 15 minutes and stored at -20oC till the RIA determination. The RIA of the plasma with the purpose of detecting the concentration of proteins specific to pregnancy was realized in two experimental series in February and December 2008, at the Laboratory for Reproduction Physiology – The Faculty of Veterinary Medicine, Liege, Belgium. The RIA dosing was realized after the application of the method with the preincubation of the serums to test with specific serum (Atg°) and then with the marked antigen (Atg*), considering the high sensitivity of this method to detect the smallest values of PAG from day 0 to day 35 after mating. The diagnosis of the pregnancy state was based on the principle of PAG antibodies binding to the specific antigen, establishing through RIA the quantity of free antigen. Non-pregnancy involves the attachment of the antigen marked by non-specific antibodies. The preliminary results have demonstrated that the sheep PAG were had values ranging between 4.197-15.985 ng/ml and 0.01-3.39 ng/ml in nonpregnant ewes. In the pregnant goats, the PAG concentrations ranged between 16.75±3.44-27.17±2.95 ng/ml, while in the nonpregnant goats, the PAG values were 1.38±0.35 – 2.03±0.51 6 ng/ml. The purpose of the experiments was to find one accurate method for early pregnancy diagnosis in goat and sheep. The conclusion was that ovine pregnancy can be reliably diagnosed on Day 25 after AI and goat pregnancy on Day 30, by using a heterologous radioimmunoassay of PAG. [less ▲]

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See detailProblématique du phosphore dans l'environnement
Renneson, Malorie ULg

Conference given outside the academic context (2010)

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See detailModeling Microbial Cross-contamination in Quick Service Restaurants by Means of Experimental Simulations With Bacillus Spores
Baptista Rodrigues, Ana Lúcia ULg; Crevecoeur, Sébastien ULg; Dure, Remi et al

Poster (2010)

Cross contamination has been frequently mentioned as being in the origin of a wide range of food borne outbreaks. Handling of food is one of the ways through which cross contamination may occur. For many ... [more ▼]

Cross contamination has been frequently mentioned as being in the origin of a wide range of food borne outbreaks. Handling of food is one of the ways through which cross contamination may occur. For many different reasons, quick service restaurants are particularly at risk. Due to its importance, cross contamination via the hands should be taken into consideration when carrying out a quantitative risk assessment. The main goal of this study was to determine transfer rates of bacteria to and via the hands, reduction rates of two hand sanitizing procedures and to apply the results to a quantitative microbial risk assessment model. According to our results, handling of a portion of raw minced meat contaminated at 4.104 cfu leads to the presence of 24 cfu on both hands, 3 cfu on ready-to-eat product (RTE) manipulated with unwashed hands, 1 cfu on RTE manipulated with wiped hands and absence on RTE manipulated with washed hands. This study provides adequate quantitative data for quantitative microbial risk assessment. [less ▲]

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See detailA non-natural variant of human lysozyme (I59T) mimics the in vitro behaviour of the I56T variant that is responsible for a form of familial amyloidosis.
Hagan, Christine L; Johnson, Russell J K; Dhulesia, Anne et al

in Protein Engineering, Design & Selection (2010), 23(7), 499-506

We report here the detailed characterisation of a non-naturally occurring variant of human lysozyme, I59T, which possesses a destabilising point mutation at the interface of the alpha- and beta-domains ... [more ▼]

We report here the detailed characterisation of a non-naturally occurring variant of human lysozyme, I59T, which possesses a destabilising point mutation at the interface of the alpha- and beta-domains. Although more stable in its native structure than the naturally occurring variants that give rise to a familial form of systemic amyloidosis, I59T possesses many attributes that are similar to these disease-associated species. In particular, under physiologically relevant conditions, I59T populates transiently an intermediate in which a region of the structure unfolds cooperatively; this loss of global cooperativity has been suggested to be a critical feature underlying the amyloidogenic nature of the disease-associated lysozyme variants. In the present study, we have utilised this variant to provide direct evidence for the generic nature of the conformational transition that precedes the ready formation of the fibrils responsible for lysozyme-associated amyloid disease. This non-natural variant can be expressed at higher levels than the natural amyloidogenic variants, enabling, for example, singly isotopically labelled protein to be generated much more easily for detailed structural studies by multidimensional NMR spectroscopy. Moreover, we demonstrate that the I59T variant can readily form fibrils in vitro, similar in nature to those of the amyloidogenic I56T variant, under significantly milder conditions than are needed for the wild-type protein. [less ▲]

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See detailThe non-core regions of human lysozyme amyloid fibrils influence cytotoxicity.
Mossuto, Maria F; Dhulesia, Anne; Devlin, Glyn et al

in Journal of Molecular Biology (2010), 402(5), 783-96

Identifying the cause of the cytotoxicity of species populated during amyloid formation is crucial to understand the molecular basis of protein deposition diseases. We have examined different types of ... [more ▼]

Identifying the cause of the cytotoxicity of species populated during amyloid formation is crucial to understand the molecular basis of protein deposition diseases. We have examined different types of aggregates formed by lysozyme, a protein found as fibrillar deposits in patients with familial systemic amyloidosis, by infrared spectroscopy, transmission electron microscopy, and depolymerization experiments, and analyzed how they affect cell viability. We have characterized two types of human lysozyme amyloid structures formed in vitro that differ in morphology, molecular structure, stability, and size of the cross-beta core. Of particular interest is that the fibrils with a smaller core generate a significant cytotoxic effect. These findings indicate that protein aggregation can give rise to species with different degree of cytotoxicity due to intrinsic differences in their physicochemical properties. [less ▲]

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See detailMitochondrial phylogeography of the edible dormouse (Glis glis) in the western Palearctic region
Hurner, Helene; Krystufek, Boris; Sara, Maurizio et al

in Journal of Mammalogy (2010), 91(1), 233-242

This study describes in detail the phylogeoraphic pattern Of the edible dormouse (Glis glis) a European rodent With pronounced hibernating behavior We Used sequences of 831 base pairs of the mitochondrial ... [more ▼]

This study describes in detail the phylogeoraphic pattern Of the edible dormouse (Glis glis) a European rodent With pronounced hibernating behavior We Used sequences of 831 base pairs of the mitochondrial DNA cytochrome-b gene from 130 edible dormice collected at 43 localities (throughout Its distribution. Our results reveal presence of 3 main haplogroups: Sicilian, South Italian (restricted to the Calabrian region) (a widespread lineage corresponding to all remaining western, central. and eastern European populations). Examination of paleontological data confirms refugial regions for G,Its in the 3 Mediterranean peninsulas, although overall low genetic diversity is found. The low diversity of the European lineage Is probably the result refugium. Other factors, such as the of a recent expansion (dated around 2.000( years ago) from a single ecological constraints oil the species, way have caused genetic bottlenecks that reinforced the low genetic variability of G glis. This work could have important implications for strategies to conserve the edible dormouse by defining important areas for their conservation DOI: 10.1644/08-MAMM-A-392R1.1 [less ▲]

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See detailBone Turnover During Pregnancy in Horses
Greiner, Claudia; Cavalier, Etienne ULg; Remy, Benoit et al

in Journal of Bone and Mineral Research (2010), 25

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See detailEcoulement de l'eau dans les sols
Degre, Aurore ULg

Learning material (2010)

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See detailOn Vershikian and I-cosy random variables and filtrations
Laurent, Stéphane ULg

in Teoriya Veroyatnostei i ee Primeneniya (2010), 55

We prove that the equivalence between Vershik’s standardness criterion and the I-cosiness criterion for a filtration in discrete, negative time, holds separately for each random variable. This gives a ... [more ▼]

We prove that the equivalence between Vershik’s standardness criterion and the I-cosiness criterion for a filtration in discrete, negative time, holds separately for each random variable. This gives a strengthening and a more direct proof of the global equivalence between these two criteria. We also provide more elementary original propositions on Vershik’s standardness criterion, while emphasizing that similar statements for I-cosiness are sometimes not so obvious. [less ▲]

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See detailOn standardness and I-cosiness
Laurent, Stéphane ULg

in Séminaire de Probabilités (2010), XLIII

The object of study of this work is the invariant characteristics of filtrations in discrete, negative time, pioneered by Vershik. We prove the equivalence between I-cosiness and standardness without ... [more ▼]

The object of study of this work is the invariant characteristics of filtrations in discrete, negative time, pioneered by Vershik. We prove the equivalence between I-cosiness and standardness without using Vershik’s standardness criterion. The equivalence between I-cosiness and productness for homogeneous filtrations is further investigated by showing that the I-cosiness criterion is equivalent to Vershik’s first level criterion separately for each random variable. We also aim to derive the elementary properties of both these criteria, and to give a survey and some complements on the published and unpublished literature. [less ▲]

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See detailCe que Bourdieu fait à la littérature.
Saint-Amand, Denis ULg

in Acta Fabula : Revue des Parutions en Théorie Littéraire (2010)

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See detailIrvin Yalom : satire et thérapie
Saint-Amand, Denis ULg

Article for general public (2010)

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