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See detailInfluence of the balls kinematics of axially loaded ball bearings on Coulombic frictional dissipations
Bozet, Jean-Luc ULg; Servais, Christophe ULg

in Journal of Tribology (2017), 139(1),

Ball bearings have been used for a long time. Nevertheless, the description of their behavior remains incomplete in spite of the large number of surveys dedicated to ball bearings. Particularly, the exact ... [more ▼]

Ball bearings have been used for a long time. Nevertheless, the description of their behavior remains incomplete in spite of the large number of surveys dedicated to ball bearings. Particularly, the exact balls kinematics has still to be addressed in depth. This paper proposes a new way to calculate the balls kinematics by using a simplified quasi-static approach for dry lubricated and axially loaded ball bearings. This method does not use the classical restrictive race control assumptions. More specifically, the role played by the balls kinematics is emphasized by means of the power dissipated within contacts between balls and races. The need for a correct evaluation of the balls behavior is illustrated by using an example, viz. a ball bearing of cryogenic engine turbopump. Indeed, the dissipated power is one of the main concerns in this particular case. [less ▲]

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See detailHabitat selection and reproduction of newts in networks of fish and fishless aquatic patches
Winandy, Laurane ULg; Legrand, Pauline ULg; Denoël, Mathieu ULg

in Animal Behaviour (2017), 123

The spatial distribution of organisms in patchy environments can be determined by the relationship between habitat quality and animal behaviour. In species with complex life cycles, such as pond-breeding ... [more ▼]

The spatial distribution of organisms in patchy environments can be determined by the relationship between habitat quality and animal behaviour. In species with complex life cycles, such as pond-breeding amphibians, the selection of a suitable wetland is crucial. While the traditional view of amphibian ecology suggests strong site fidelity and low vagility, more recent research highlights mechanisms involving active site choice through avoidance behaviour and bet-hedging strategies in heterogeneous environments. The introduction of fish to the aquatic environment is one of the factors that may alter site selection and lead to local dispersal. In this context, we investigated the habitat choice of Alpine newts, Ichthyosaura alpestris, in networks of fish (Carassius auratus) and fishless aquatic patches. Using a laboratory design consisting of aquaria divided into two water tanks connected by a terrestrial platform, we assessed newt distribution and movement between patches. During the breeding period, we compared the reproductive success of individuals in two types of networks. We found that newts escaped fish by rapidly changing aquatic patches and then aggregating in safe aquatic patches that were free of fish. In the fish network, newts maintained reproduction, but the high local abundance resulted in decreased sexual activity and egg production and increased use of the terrestrial habitat. However, in the fishless network, newts moved between aquatic patches several times, exhibited more courtship behaviour and laid more eggs than they did in the fish networks. Our results showed both adaptive habitat switching due to environmental risks in the fish network and habitat supplementation (i.e. use of alternative resources) in the fishless network. Such studies on movement behaviour and habitat selection have conservation implications in showing that the persistence of native species in invaded networks depends on the rescue effect, with immigration to fish-free habitats potentially preventing local extinction. [less ▲]

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See detailFirst Report of Candidatus Liberibacter solanacearum Associated with the Psyllid Bactericera trigonica Hodkinson on Carrots in Northern Africa
Tahzima, R.; Massart, Sébastien ULg; Achbani, E.H. et al

in Plant Disease (2017), 101(1), 242

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See detailOpinion Statement ECJ-TF 2/2016 on the Decision of the Court of Justice of the European Union of 13 July 2016 in Brisal and KBC Finance Ireland (Case C-18/15), on the Admissibility of Gross Withholding Tax of Interest
Richelle, Isabelle ULg; Prats, Alfredo Garcia; Haslehner, Werner et al

in European Taxation (2017), 2017

This Opinion Statement of the CFE ECJ Task Force analyses the ECJ’ s decision in Brisal and KBC Finance Ireland (Case C-18/15) of 13 July 2016. Following a Portuguese reference for a preliminary ruling ... [more ▼]

This Opinion Statement of the CFE ECJ Task Force analyses the ECJ’ s decision in Brisal and KBC Finance Ireland (Case C-18/15) of 13 July 2016. Following a Portuguese reference for a preliminary ruling, the Court’ s decision provides further clarification on the permissibility of withholding taxation within the European Union. In relation to interest, the Court held that non-resident taxpayers may be subject to withholding taxes (even if comparable residents pursuing the same activity are not) but that non-residents may nevertheless not be taxed on gross income (when comparable residents are taxed on net profits) and are, therefore, entitled to deduct expenses directly connected to their business activity [less ▲]

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See detailGoat breeding in the rural district of Chemini (Algeria)
Moula, Nassim ULg; Ait Kaki, Asma; Touazi, Leghel et al

in Nature & Technology (2017), n° 16/Janvier

The Kabyle goat breed represents 10.52% of the total Algerian market (3.8 million heads). A survey of 69 farmers has been carried out in order to characterize it and its breeding in the District of ... [more ▼]

The Kabyle goat breed represents 10.52% of the total Algerian market (3.8 million heads). A survey of 69 farmers has been carried out in order to characterize it and its breeding in the District of Chemini. The questions focused on household agricultural activities, including breeding of goats, cattle, sheep, rabbits, chicken, turkeys, honeybees and the production of olive oil and figs. The goat morpho-biometric characterization was based on 18 corporal measurements. The Hierarchical Cluster Analysis (HCA) of the farm structures defined four groups of farms, variance between groups accounting for 55.7% of total variability. The average number of goats in groups 1 to 4 was 7.2±2.8, 11.1±3.5, 22.3±1.4 and 3.4±1.0, respectively. Group 3 (n=6), showed the greatest number; it consists of older farmers (67 years old or over) not practicing arboriculture. They also have the largest numbers of sheep (48.67), rabbits (50.83), chicken (48.33) and turkeys (42). Group 4 (n=9), with the lowest number of goats, was the group of young farmers (39 years old or less), more dedicated to cattle breeding (~52 heads) and the production of olive oil (~207 trees) and figs (~47 trees). The 18 morpho-biometric variables were significantly higher in males than in females (p<0.05). The Kabyle goat is small (Height at withers: male: 68.23±0.97cm and female: 65.41±0.55cm) with long hair (male: 12.24±0.51cm, and female: 9.51±0.29cm). Its ears are drooping, its convex profile has a slightly pronounced nasal split and its dress color ranges from dark brown to black. This adapted genetic resource should be key in the development of a local production, based on a strong commitment of farmers inside a breed association, for the production of specimens corresponding to a standard, to be determined collectively. [less ▲]

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See detailImpact of the cumulated proteins and energy deficits on ICU patient’s outcome
PAGE, Isaline ULg; Warnier, Stéphanie; NYS, Monique ULg et al

in Annals of Intensive Care (2017, January), 7(Suppl1), 200

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See detailSelf-Administration of Medicines and Dietary Supplements Among Female Amateur Runners: A Cross-Sectional Analysis.
Locquet, Médéa ULg; Beaudart, Charlotte ULg; Larbuisson, Robert ULg et al

in Advances in Therapy (2017), 33(12), 2257-2268

INTRODUCTION: Self-administration of medicines or dietary supplements without any physician's advice is a widespread behavior and appears to be more frequently practiced by women. Moreover, reasons to ... [more ▼]

INTRODUCTION: Self-administration of medicines or dietary supplements without any physician's advice is a widespread behavior and appears to be more frequently practiced by women. Moreover, reasons to self-administer products are often pains and injuries especially among athletes who might also use remedies to improve physical performance. The objective of this study was thus to assess the prevalence of self-administration of medicines and dietary supplements as well as its determinants among female amateur runners. METHODS: Our sample was comprised of women who took part in amateur running events. Data regarding self-administration of substances, exclusively aiming at being physically prepared for the running event (i.e., intake the week before), were collected through an anonymous self-administered questionnaire including four specific themes (i.e., general information, self-administered medicines and dietary supplements, context of self-administration of substances and knowledge of the anti-doping regulations). RESULTS: A total of 136 women, with a median age of 39 years (interquartile range: 27-47), volunteered. Among them, 34.6% reported self-administration of medicines during the period immediately preceding the running event, with the aim to be physically prepared. More than one third (33.8%) also declared self-administration of dietary supplements. Furthermore, we observed that about 8.1% of the sample had consumed a potentially doping substance. After adjustments for confounding variables, the probability of self-administration of products (medicines or supplements) increased significantly with the intensity of the activity and the membership in a sports club. CONCLUSIONS: Our study showed that self-administration of products among female runners seems to be a widespread behavior, where the intensity of the sports practice and the network of runners seem to influence the decision to resort to this behavior. [less ▲]

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See detailHealth Outcomes of Sarcopenia: A Systematic Review and Meta-Analysis.
Beaudart, Charlotte ULg; Zaaria, Myriam; Pasleau, Françoise ULg et al

in PLoS ONE (2017), 12(1), 0169548

OBJECTIVE: The purpose of this study was to perform a systematic review to assess the short-, middle- and long-term consequences of sarcopenia. METHODS: Prospective studies assessing the consequences of ... [more ▼]

OBJECTIVE: The purpose of this study was to perform a systematic review to assess the short-, middle- and long-term consequences of sarcopenia. METHODS: Prospective studies assessing the consequences of sarcopenia were searched across different electronic databases (MEDLINE, EMBASE, EBM Reviews, Cochrane Database of Systematic Reviews, EBM Reviews ACP Journal Club, EBM Reviews DARE and AMED). Only studies that used the definition of the European Working Group on Sarcopenia in Older People to diagnose sarcopenia were included. Study selection and data extraction were performed by two independent reviewers. For outcomes reported by three or more studies, a meta-analysis was performed. The study results are expressed as odds ratios (OR) with 95% CI. RESULTS: Of the 772 references identified through the database search, 17 were included in this systematic review. The number of participants in the included studies ranged from 99 to 6658, and the duration of follow-up varied from 3 months to 9.8 years. Eleven out of 12 studies assessed the impact of sarcopenia on mortality. The results showed a higher rate of mortality among sarcopenic subjects (pooled OR of 3.596 (95% CI 2.96-4.37)). The effect was higher in people aged 79 years or older compared with younger subjects (p = 0.02). Sarcopenia is also associated with functional decline (pooled OR of 6 studies 3.03 (95% CI 1.80-5.12)), a higher rate of falls (2/2 studies found a significant association) and a higher incidence of hospitalizations (1/1 study). The impact of sarcopenia on the incidence of fractures and the length of hospital stay was less clear (only 1/2 studies showed an association for both outcomes). CONCLUSION: Sarcopenia is associated with several harmful outcomes, making this geriatric syndrome a real public health burden. [less ▲]

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See detailMolecular-Based Recursive Partitioning Analysis Model for Glioblastoma in the Temozolomide Era: A Correlative Analysis Based on NRG Oncology RTOG 0525.
Bell, Erica Hlavin; Pugh, Stephanie L.; McElroy, Joseph P. et al

in JAMA Oncology (2017)

Importance: There is a need for a more refined, molecularly based classification model for glioblastoma (GBM) in the temozolomide era. Objective: To refine the existing clinically based recursive ... [more ▼]

Importance: There is a need for a more refined, molecularly based classification model for glioblastoma (GBM) in the temozolomide era. Objective: To refine the existing clinically based recursive partitioning analysis (RPA) model by incorporating molecular variables. Design, Setting, and Participants: NRG Oncology RTOG 0525 specimens (n = 452) were analyzed for protein biomarkers representing key pathways in GBM by a quantitative molecular microscopy-based approach with semiquantitative immunohistochemical validation. Prognostic significance of each protein was examined by single-marker and multimarker Cox regression analyses. To reclassify the prognostic risk groups, significant protein biomarkers on single-marker analysis were incorporated into an RPA model consisting of the same clinical variables (age, Karnofsky Performance Status, extent of resection, and neurologic function) as the existing RTOG RPA. The new RPA model (NRG-GBM-RPA) was confirmed using traditional immunohistochemistry in an independent data set (n = 176). Main Outcomes and Measures: Overall survival (OS). Results: In 452 specimens, MGMT (hazard ratio [HR], 1.81; 95% CI, 1.37-2.39; P < .001), survivin (HR, 1.36; 95% CI, 1.04-1.76; P = .02), c-Met (HR, 1.53; 95% CI, 1.06-2.23; P = .02), pmTOR (HR, 0.76; 95% CI, 0.60-0.97; P = .03), and Ki-67 (HR, 1.40; 95% CI, 1.10-1.78; P = .007) protein levels were found to be significant on single-marker multivariate analysis of OS. To refine the existing RPA, significant protein biomarkers together with clinical variables (age, Karnofsky Performance Status, extent of resection, and neurological function) were incorporated into a new model. Of 166 patients used for the new NRG-GBM-RPA model, 97 (58.4%) were male (mean [SD] age, 55.7 [12.0] years). Higher MGMT protein level was significantly associated with decreased MGMT promoter methylation and vice versa (1425.1 for methylated vs 1828.0 for unmethylated; P < .001). Furthermore, MGMT protein expression (HR, 1.84; 95% CI, 1.38-2.43; P < .001) had greater prognostic value for OS compared with MGMT promoter methylation (HR, 1.77; 95% CI, 1.28-2.44; P < .001). The refined NRG-GBM-RPA consisting of MGMT protein, c-Met protein, and age revealed greater separation of OS prognostic classes compared with the existing clinically based RPA model and MGMT promoter methylation in NRG Oncology RTOG 0525. The prognostic significance of the NRG-GBM-RPA was subsequently confirmed in an independent data set (n = 176). Conclusions and Relevance: This new NRG-GBM-RPA model improves outcome stratification over both the current RTOG RPA model and MGMT promoter methylation, respectively, for patients with GBM treated with radiation and temozolomide and was biologically validated in an independent data set. The revised RPA has the potential to contribute to improving the accurate assessment of prognostic groups in patients with GBM treated with radiation and temozolomide and to influence clinical decision making. Trial Registration: clinicaltrials.gov Identifier: NCT00304031. [less ▲]

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See detailConcise Reviews: Regeneration in Mammalian Cochlea Hair Cells: Help from Supporting Cells Transdifferentiation.
Franco, Benedicte; Malgrange, Brigitte ULg

in Stem cells (Dayton, Ohio) (2017)

It is commonly assumed that mammalian cochlear cells do not regenerate. Therefore, if hair cells are lost following an injury, no recovery could occur. However, during the first postnatal week, mice ... [more ▼]

It is commonly assumed that mammalian cochlear cells do not regenerate. Therefore, if hair cells are lost following an injury, no recovery could occur. However, during the first postnatal week, mice harbor some progenitor cells that retain the ability to give rise to new hair cells. These progenitor cells are in fact supporting cells. Upon hair cells loss, those cells are able to generate new hair cells both by direct transdifferentiation or following cell cycle re-entry and differentiation. However, this property of supporting cells is progressively lost after birth. Here, we review the molecular mechanisms that are involved in mammalian hair cell development and regeneration. Manipulating pathways used during development constitute good candidates for inducing hair cell regeneration after injury. Despite these promising studies, there is still no evidence for a recovery following hair cells loss in adult mammals. Stem Cells 2017. [less ▲]

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See detailInfluence of the crustal magnetic field on the Mars aurora electron flux and UV brightness
Bisikalo, D. V.; Shematovich, V. I.; Gérard, Jean-Claude ULg et al

in Icarus (2017), 282

Observations with the SPICAM instrument on board Mars Express have shown the occasional presence of localized ultraviolet nightside emissions associated with enhanced energetic electron fluxes. These ... [more ▼]

Observations with the SPICAM instrument on board Mars Express have shown the occasional presence of localized ultraviolet nightside emissions associated with enhanced energetic electron fluxes. These features generally occur in regions with significant radial crustal magnetic field. We use a Monte-Carlo electron transport model to investigate the role of the magnetic field on the downward and upward electron fluxes, the brightness and the emitted power of auroral emissions. Simulations based on an ASPERA-3 measured auroral electron precipitation indicate that magnetic mirroring leads to an intensification of the energy flux carried by upward moving electrons- from about 20% in the absence of crustal magnetic field up to 33-78% when magnetic field is included depending on magnetic field topology. Conservation of the particle flux in a flux tube implies that the presence of the B-field does not appreciably modify the emission rate profiles for an initially isotropic pitch angle distribution. However, we find that crustal magnetic field results in increase of the upward electron flux, and, consequently, in reduction of the total auroral brightness for given energy flux of precipitating electrons. [less ▲]

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See detailMars Topography Investigated Through the Wavelet Leaders Method: a Multidimensional Study of its Fractal Structure
Deliège, Adrien ULg; Kleyntssens, Thomas ULg; Nicolay, Samuel ULg

in Planetary and Space Science (2017), 136C

This work examines the scaling properties of Mars topography through a wavelet-based formalism. We conduct exhaustive one-dimensional (both longitudinal and latitudinal) and two-dimensional studies based ... [more ▼]

This work examines the scaling properties of Mars topography through a wavelet-based formalism. We conduct exhaustive one-dimensional (both longitudinal and latitudinal) and two-dimensional studies based on Mars Orbiter Laser Altimeter (MOLA) data using the multifractal formalism called Wavelet Leaders Method (WLM). This approach shows that a scale break occurs at approximately 15 km, giving two scaling regimes in both 1D and 2D cases. At small scales, these topographic profiles mostly display a monofractal behavior while a switch to multifractality is observed in several areas at larger scales. The scaling exponents extracted from this framework tend to be greater at small scales. In the 1D context, these observations are in agreement with previous works and thus suggest that the WLM is well-suited for examining scaling properties of topographic fields. Moreover, the 2D analysis is the first such complete study to our knowledge. It gives both a local and global insight on the scaling regimes of the surface of Mars and allows to exhibit the link between the scaling exponents and several famous features of the Martian topography. These results may be used as a solid basis for further investigations of the scaling laws of the Red planet and show that the WLM could be used to perform systematic analyses of the surface roughness of other celestial bodies. [less ▲]

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See detailApplication of a 3D unsteady surface panel method with flow separation model to horizontal axis wind turbines
Prasad, Chandra Shekhar; Dimitriadis, Grigorios ULg

in Journal of Wind Engineering & Industrial Aerodynamics (2017), 166

This work describes the development and application of a 3D unsteady surface panel method with a separation model to the problem of simulating the flow around the blades of a horizontal axis wind turbine ... [more ▼]

This work describes the development and application of a 3D unsteady surface panel method with a separation model to the problem of simulating the flow around the blades of a horizontal axis wind turbine. The present method is intended as a design tool to capture the 3D time-dependent characteristics of both attached and separated flow conditions and is an extension of previous 2D approaches. Flow separation is modelled using a loose coupling procedure between the inviscid panel method and a quasi-3D viscous boundary layer solution. A separated wake is shed at the predicted separation points and propagated at the local flow velocity, just like the trailing edge wake. The methodology is demonstrated on the NREL phase-VI wind turbine test case and the model predictions are compared to experimental measurements. [less ▲]

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See detailMamlūk Cairo: A Crossroad for Embassies
Bauden, Frédéric ULg; Dekkiche, Malika

Book published by Brill Academic Publishers (2017)

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See detailA Reconstructed Qarā Qoyūnlū Letter
Bauden, Frédéric ULg

in Bauden, Frédéric; Dekkiche, Malika (Eds.) Mamlūk Cairo: A Crossroad for Embassies (2017)

Detailed reference viewed: 55 (9 ULg)
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See detailLa bibliothèque d'Antoine Galland
Bauden, Frédéric ULg

in Bauden, Frédéric; Waller, Richard (Eds.) Antoine Galland (1646-1715) et son Journal. Actes du colloque international organisé à l’Université de Liège (16-18 janvier 2015) à l’occasion du tricentenaire de sa mort (2017)

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See detailMamluk Diplomatics: The Present State of Research
Bauden, Frédéric ULg

in Bauden, Frédéric; Dekkiche, Malika (Eds.) Mamlūk Cairo: A Crossroad for Embassies (2017)

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See detailLists of Gifts in the Mamluk Diplomatic Tradition
Bauden, Frédéric ULg

in Bauden, Frédéric (Ed.) Culture matérielle et contacts diplomatiques entre l’Occident latin, Byzance et l’Orient islamique (XIe-XVIe siècle) (2017)

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See detailThe Mamlūk Sultanate and Its Periphery
Bauden, Frédéric ULg

Book published by Brill Academic Publishers (2017)

Detailed reference viewed: 33 (0 ULg)