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See detailAnalysis of the Structure and Function of FOX-4 Cephamycinase
Lefurgy, S.T.; Malashkevich, V.N.; Aguilan, J.T. et al

in Antimicrobial Agents and Chemotherapy (2016), 60(2), 717-728

Class C β-lactamases poorly hydrolyze cephamycins (e.g., cefoxitin, cefotetan, and moxalactam). In the past 2 decades, a new family of plasmid-based AmpC β-lactamases conferring resistance to cefoxitin ... [more ▼]

Class C β-lactamases poorly hydrolyze cephamycins (e.g., cefoxitin, cefotetan, and moxalactam). In the past 2 decades, a new family of plasmid-based AmpC β-lactamases conferring resistance to cefoxitin, the FOX family, has grown to include nine unique members descended from the Aeromonas caviae chromosomal AmpC. To understand the basis for the unique cephamycinase activity in the FOX family, we determined the first X-ray crystal structures of FOX-4, apo enzyme and the acyl-enzyme with its namesake compound, cefoxitin, using the Y150F deacylation-deficient variant. Notably, recombinant expression of N-terminally tagged FOX-4 also yielded an inactive adenylylated enzyme form not previously observed in β-lactamases. The posttranslational modification (PTM), which occurs on the active site Ser64, would not seem to provide a selective advantage, yet might present an opportunity for the design of novel antibacterial drugs. Substantial ligand-induced changes in the enzyme are seen in the acyl-enzyme complex, particularly the R2 loop and helix H10 (P289 to N297), with movement of F293 by 10.3 Å. Taken together, this study provides the first picture of this highly proficient class C cephamycinase, uncovers a novel PTM, and suggests a possible cephamycin resistance mechanism involving repositioning of the substrate due to the presence of S153P, N289P, and N346I substitutions in the ligand binding pocket. [less ▲]

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See detailTEST-RETEST RELIABILITY OF TWO CLINICAL TESTS FOR THE ASSESSMENT OF HIP ABDUCTOR ENDURANCE IN HEALTHY FEMALES
Van Cant, Joachim; Dumont, Gregory; Pitance, Laurent et al

in The International Journal of Sports Physical Therapy (2016), 11(1), 24-33

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See detailLes conseils scientifiques des institutions de conservation de la nature et de développement durable. Une approche par le vécu d’instances entre science et politique.
arpin, isabelle; cosson, arnaud; Denayer, Dorothée ULg et al

in SCIENCES ET BIODIVERSITÉ. Acteurs, enjeux, temporalités (2016)

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See detail50 ans d'exploration de la planète Mars
Stiepen, Arnaud ULg

Conference given outside the academic context (2016)

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See detailLa pauvreté infantile et juvénile en Fédération Wallonie-Bruxelles
Guio, Anne-Catherine; Baye, Ariane ULg

Report (2016)

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See detailCrossoads février 2016 - chaque mercredi 18h-20h
Sacré, Robert ULg

Diverse speeche and writing (2016)

Magazine sonore du blues et des musiques américaines ( séquences R&B, Soul, Zydeco, Gospel,jazz, etc...)

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See detailSHANNA WATERSTOWN La tornade noire venue de Floride
Sacré, Robert ULg

in ABS Magazine (2016), (49),

Interview de la chanteuse noire américaine Shanna Waterstown ; son histoire et son parcours artistique

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See detailPredicting Review Helpfulness
Ittoo, Ashwin ULg

in Proceedings (2016, February)

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See detailThe impact of dissolved organic carbon and bacterial respiration on pCO2 in experimental sea ice
Zhou, Jiayun; Kotovitch, Marie ULg; Kaartokallio, H. et al

in Progress in Oceanography (2016), 141

Previous observations have shown that the partial pressure of carbon dioxide (pCO2) in sea ice brines is generally higher in Arctic sea ice compared to those from the Antarctic sea ice, especially in ... [more ▼]

Previous observations have shown that the partial pressure of carbon dioxide (pCO2) in sea ice brines is generally higher in Arctic sea ice compared to those from the Antarctic sea ice, especially in winter and early spring. We hypothesized that these differences result from the higher dissolved organic carbon (DOC) content in Arctic seawater: Higher concentrations of DOC in seawater would be reflected in a greater DOC incorporation into sea ice, enhancing bacterial respiration, which in turn would increase the pCO2 in the ice. To verify this hypothesis, we performed an experiment using two series of mesocosms: one was filled with seawater (SW) and the other one with seawater with an addition of filtered humic-rich river water (SWR). The addition of river water increased the DOC concentration of the water from a median of 142 µmol L-1 in SW to 249 µmol L-1 in SWR. Sea ice was grown in these mesocosms under the same physical conditions over 19 days. Microalgae and protists were absent, and only bacterial activity has been detected. We measured the DOC concentration, bacterial respiration, total alkalinity and pCO2 in sea ice and the underlying seawater, and we calculated the changes in dissolved inorganic carbon (DIC) in both media. We found that bacterial respiration in ice was higher in SWR: median bacterial respiration was 25 nmol C L-1 h-1 compared to 10 nmol C L-1 h-1 in SW. pCO2 in ice was also higher in SWR with a median of 430 ppm compared to 356 ppm in SW. However, the differences in pCO2 were larger within the ice interiors than at the surfaces or the bottom layers of the ice, where exchanges at the air-ice and ice-water interfaces might have reduced the differences. In addition, we used a model to simulate the differences of pCO2 and DIC based on bacterial respiration. The model simulations support the experimental findings and further suggest that bacterial growth efficiency in the ice might be 0.15-0.2. It is thus credible that the higher pCO2 in Arctic sea ice brines compared with those from the Antarctic sea ice were due to an elevated bacterial respiration, sustained by higher riverine DOC loads. These conclusions should hold for locations and time frames when bacterial activity is relatively dominant compared to algal activity, considering our experimental conditions. [less ▲]

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See detailDecision Making from Confidence Measurement on the Reward Growth using Supervised Learning: A Study Intended for Large-Scale Video Games
Taralla, David ULg; Qiu, Zixiao ULg; Sutera, Antonio ULg et al

in Proceedings of the 8th International Conference on Agents and Artificial Intelligence (ICAART 2016) - Volume 2 (2016, February)

Video games have become more and more complex over the past decades. Today, players wander in visually and option- rich environments, and each choice they make, at any given time, can have a combinatorial ... [more ▼]

Video games have become more and more complex over the past decades. Today, players wander in visually and option- rich environments, and each choice they make, at any given time, can have a combinatorial number of consequences. However, modern artificial intelligence is still usually hard-coded, and as the game environments become increasingly complex, this hard-coding becomes exponentially difficult. Recent research works started to let video game autonomous agents learn instead of being taught, which makes them more intelligent. This contribution falls under this very perspective, as it aims to develop a framework for the generic design of autonomous agents for large-scale video games. We consider a class of games for which expert knowledge is available to define a state quality function that gives how close an agent is from its objective. The decision making policy is based on a confidence measurement on the growth of the state quality function, computed by a supervised learning classification model. Additionally, no stratagems aiming to reduce the action space are used. As a proof of concept, we tested this simple approach on the collectible card game Hearthstone and obtained encouraging results. [less ▲]

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See detailHyaluronic acid and tendon lesions
Kaux, Jean-François ULg; SAMSON, Antoine; Crielaard, Jean-Michel ULg

in Muscles, Ligaments and Tendons Journal (2016), 5(4 (eCollection 2015 Oct-Dec)), 264-269

Introduction: Recently, the viscoelastic properties of hyaluronic acid on liquid connective tissue have been proposed for the treatment of tendinopathies. Some fundamental studies show encouraging results ... [more ▼]

Introduction: Recently, the viscoelastic properties of hyaluronic acid on liquid connective tissue have been proposed for the treatment of tendinopathies. Some fundamental studies show encouraging results on hyaluronic acid’s ability to promote tendon gliding and reduce adhesion as well as to improve tendon architectural organisation. Some observations also support its use in a clinical setting to improve pain and function. This literature review analyses studies relating to the use of hyaluronic acid in the treatment of tendinopathies. Methods: This review was constructed using the Medline database via Pubmed, Scopus and Google Scholar. The keywords hyaluronic acid, tendon and tendinopathy were used for the research. Results: In total, 27 articles (in English and French) on the application of hyaluronic acid to tendons were selected for their relevance and scientific quality, including eight for the 'in vitro' part, three for the 'in vivo' animal part and six for the human section. Conclusions: Preclinical studies demonstrate encouraging results: HA permits tendon gliding, reduces adhesions, creates better tendon architectural organisation and limits inflammation. These laboratory observations appear to be supported by limited but encouraging short-term clinical results on pain and function. However, controlled randomised studies are still needed. [less ▲]

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See detailTraumatologie du rugby à VII
KAUX, Jean-François ULg; Julia, Marc; Delvaux, François ULg et al

in Science & Sports (2016), 31(1), 1-5

Aims. — To estimate the risk of injury in rugby sevens.News. — The rugby sevens is an increasingly popular sport since the creation of the IRB SevensWorld Series in 2000 and its introduction as an Olympic ... [more ▼]

Aims. — To estimate the risk of injury in rugby sevens.News. — The rugby sevens is an increasingly popular sport since the creation of the IRB SevensWorld Series in 2000 and its introduction as an Olympic sport in 2016. Despite its strong simi-larities to rugby union, it remains a different sport with higher game intensity, causing a moresignificant number of injuries. The average incidence of injury in rugby sevens is 249.27 for1000 hours of play against 102.25 for 1000 hours of rugby union matches.Conclusion. — This epidemiological review of injuries among the rugby sevens refers to theirlocation and their nature, the causes, the position of players, the type of field, as well as thedowntime of practice following trauma. [less ▲]

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See detailLINKING CATTLE GRAZING BEHAVIOR TO METHANE AND CARBON DIOXIDE DYNAMICS
Blaise, Yannick ULg; Lebeau, Frédéric ULg; Andriamandroso, Andriamasinoro ULg et al

in Communications in Agricultural and Applied Biological Sciences (2016, February), 81(1), 107-112

Various methods are presently used to measure methane (CH4) emissions of ruminants on pasture. Those measurements are essential to evaluate nutritional strategies to mitigate enteric CH4 emissions as well ... [more ▼]

Various methods are presently used to measure methane (CH4) emissions of ruminants on pasture. Those measurements are essential to evaluate nutritional strategies to mitigate enteric CH4 emissions as well as addressing the selection of low producing individuals. On pasture and in the barn, variations in CH4 emissions are observed depending on the time of the day. However, no studies have been made to link these diurnal fluctuations to behavioural phases, especially on pasture. The aim of this study was to understand the individual dynamics of CH4 production and their links to the grazing behaviour. For this purpose, a new tool was specifically developed. Five red-pied dry cows were equipped with infrared CH4 and carbon dioxide (CO2) sensors measuring concentrations in the exhaled air at 4 Hz. The animals were equipped with a heart rate belt (HR) and motion sensors to detect their feeding behaviours (grazing vs. rumination) for periods of 8 h/d. Wind speed (WS) was also monitor to verify interference with sampled gas concentrations. Results showed that using the CH4:CO2 ratio reduced the interference with WS that was observed on raw CH4 and CO2 concentration signals. CH4:CO2 ratio average over 5 min periods indicated that CH4 emissions were lower during grazing than rumination (P<0.01). The eructation frequency during grazing (0.48 eructation/min, P<0.01) was also lower than during rumination (0.65 eructation/min). HR was higher during grazing that rumination. Because HR is usually linked to metabolic CO2 production intensity, hence influencing the denominator of the CH4:CO2 ratio, further investigation should focus on the quantification of changes in fermentative and metabolic CO2 emissions along the day to estimate total CH4 production more accurately and the relationship between CH4 emissions patterns and post-feeding times. [less ▲]

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See detailLa religion des rois des Belges
Bechet, Christophe ULg

Article for general public (2016)

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See detailTransfer of contaminants in the food chain up to marine mammals
Das, Krishna ULg

Conference (2016, February)

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See detailPrise en charge des patients en état de conscience altérée. Approche kinésithérapique par stimulations transcrâniennes non invasives et attèles souples
Martens, Géraldine ULg

in Kinésithérapie, la revue. Vol 16 - n°170 (2016, February)

Ces dernières années, grâce au perfectionnement des techniques de réanimation, le nombre de patients survivant à leur lésion cérébrale a fortement augmenté. Tandis que certains se rétablissent rapidement ... [more ▼]

Ces dernières années, grâce au perfectionnement des techniques de réanimation, le nombre de patients survivant à leur lésion cérébrale a fortement augmenté. Tandis que certains se rétablissent rapidement, d’autres traversent différents états de conscience altérée (coma, état végétatif/non répondant ou état de conscience minimale) avant de récupérer ou non un état de conscience normal. Les patients en état de conscience altérée représentent un problème majeur tant au niveau diagnostique, pronostique, thérapeutique, qu’au niveau de leur prise en charge quotidienne. Diverses possibilités de traitements pharmacologiques et non pharmacologiques ont été étudiées. Les techniques des stimulations transcrâniennes à courant continu (tDCS) augmentent l’excitabilité corticale et le flux sanguin cérébral régional. La plasticité cérébrale s’en voit améliorée, ce qui module l’activité corticale et donc l’activité fonctionnelle des aires se trouvant sous l’anode. Une plasticité cérébrale est parfois encore possible, même au stade chronique. Un des problèmes majeurs de ces patients est la spasticité qui cause diverses complications (rétractions musculaires, subluxations et luxations articulaires, escarres, positions vicieuses) en plus du facteur algique. Ces complications sont d’autant plus importantes que ces patients sont voués à rester alités. La kinésithérapie permet de réduire les complications liées à la spasticité mais est parfois insuffisante et la prise d’antispastiques est inévitable. La technique la plus couramment utilisée est l’étirement passif : son efficacité dans la réduction des phénomènes spastiques est clairement reconnue. Par ailleurs, des études ont montré l’intérêt de la mise en place d’une attèle souple au niveau du membre supérieur chez les patients spastiques. L’avantage de cette technique est sa simplicité d’utilisation. Cette attelle se base sur le principe de saturation du système proprioceptif cutané à l’aide d’un tissu élastique, ceci simultanément à un rééquilibrage des antagonistes. De nombreuses pistes restent encore à explorer pour une prise en charge optimale des patients cérébrolésés. [less ▲]

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See detailOUTDOOR MEASUREMENT OF CATTLE METHANE EMISSIONS USING THE EDDY-COVARIANCE TECHNIQUE IN COMBINATION WITH GEOLOCALIZATION DEVICES
Dumortier, Pierre ULg; Andriamandroso, Andriamasinoro ULg; Aubinet, Marc ULg et al

Poster (2016, February)

Methane emissions account for 8% of the EU-15 GHG emissions and livestock generates approximately half of these emissions [1]. In order to improve emissions reporting and properly test mitigation options ... [more ▼]

Methane emissions account for 8% of the EU-15 GHG emissions and livestock generates approximately half of these emissions [1]. In order to improve emissions reporting and properly test mitigation options, techniques for measuring methane emissions from cattle must be developed and adapted to each management system. Among available micrometeorological methods, the use of eddy-covariance is still in its infancy [2] and its relevance and robustness for cattle flux estimation has still to be proved. On one hand, it is well adapted to seasonal grazing systems, is non-invasive, needs little animal handling and allows detection of daily emission patterns. On the other hand, it has the drawback of requiring cattle geo-localization and long periods of measurements (typically one month). In this study, we combined measured CH4 fluxes with a footprint model [3] and cattle positions (GPS devices) over several one-month campaigns at key periods in the grazing season in order to obtain CH4 emissions per cow at herd scale. Accelerometers were also added to the system for behaviour detection, opening the possibility of linking emissions to feeding behaviour. Measurements were performed and are still ongoing at the Dorinne Terrestrial Observatory in 2014/2015. The first campaign provided a mean emission per cow of 65±6 kg CH4.LSU-1.year-1. Cattle emission pattern was tightly linked with behaviour pattern, emissions being higher during and shortly after grazing (i.e. at dawn and dusk). Uncertainties linked to the method will be discussed and quantified (footprint model validity, geo-localization precision, eddy covariance corrections and filtering specificities linked to CH4 measurements). Compilation of data from multiple campaigns will allow quantification of the effects of forage quality, animal weight and lactating state on emissions per cow. [less ▲]

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See detailFramework for Threat Based Failure Rates in Transmission System Operation
Perkin, Samuel; Bjornsson, Gudjon; Baldursdottir, Iris et al

in Framework for Threat Based Failure Rates in Transmission System Operation (2016, February)

Reliability of electrical transmission systems isvpresently managed by applying the deterministic N-1 criterion, or some variant thereof. This means that transmission systems are designed with at least ... [more ▼]

Reliability of electrical transmission systems isvpresently managed by applying the deterministic N-1 criterion, or some variant thereof. This means that transmission systems are designed with at least one level of redundancy, regardless of the cost of doing so, or the severity of the risks they mitigate. In an operational context, the N-1 criterion provides a reliability target but it fails to accurately capture the dynamic nature of short-term threats to transmission systems. Ongoing research aims to overcome this shortcoming by proposing new probabilistic reliability criteria. Such new criteria are anticipated to rely heavily on component failure rate calculations. This paper provides a threat modelling framework, using the Icelandic transmission system as an example, highlighting the need for improved data collection and failure rate modelling. The feasibility of using threat credibility indicators to achieve spatio-temporal failure rates, given minimal data, is explored in a case study of the Icelandic transmission system. The paper closes with a discussion on the assumptions and simplifications that are implicitly made in the formulation, and the additional work required for such an approach to be included in existing practices. Specifically, this paper is concerned only with short term and real-time management of electrical transmission systems. [less ▲]

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