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See detailA new look at Herrmann's formulation of incompressibility
Debongnie, Jean-François ULg

in Wellford, L.; Carter, Jr. (Eds.) Proceedings of the symposium on applications of computer methods in engineering (vol.2) (1977, August)

An exposition of Herrmann's formulation is given first, and its extension to the anisotropic case is presented following a new way. Using this method, the matrix of material coefficients can be calculated ... [more ▼]

An exposition of Herrmann's formulation is given first, and its extension to the anisotropic case is presented following a new way. Using this method, the matrix of material coefficients can be calculated in a fully automated manner. The existence of the solution is briefly discussed next. A necessary and sufficient condition is obtained which turns to be of unpratical use. Fortunately, this condition is in most practical cases equivalent to another one, which is of fairly simple use. These concepts are illustrated by an example. [less ▲]

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See detailA New Look at Ichthyosaur Long Bone Microanatomy and Histology: Implications for Their Adaptation to an Aquatic Life
Houssaye, Alexandra; Scheyer, Torsten; Kolb, Christian et al

in PLoS ONE (2014), 9(4), 95637

Background Ichthyosaurs are Mesozoic reptiles considered as active swimmers highly adapted to a fully open-marine life. They display a wide range of morphologies illustrating diverse ecological grades ... [more ▼]

Background Ichthyosaurs are Mesozoic reptiles considered as active swimmers highly adapted to a fully open-marine life. They display a wide range of morphologies illustrating diverse ecological grades. Data concerning their bone microanatomical and histological features are rather limited and suggest that ichthyosaurs display a spongious, “osteoporotic-like” bone inner structure, like extant cetaceans. However, some taxa exhibit peculiar features, suggesting that the analysis of the microanatomical and histological characteristics of various ichthyosaur long bones should match the anatomical diversity and provide information about their diverse locomotor abilities and physiology. Methodology/Principal Findings The material analyzed for this study essentially consists of mid-diaphyseal transverse sections from stylopod bones of various ichthyosaurs and of a few microtomographic (both conventional and synchrotron) data. The present contribution discusses the histological and microanatomical variation observed within ichthyosaurs and the peculiarities of some taxa (Mixosaurus, Pessopteryx). Four microanatomical types are described. If Mixosaurus sections differ from those of the other taxa analyzed, the other microanatomical types, characterized by the relative proportion of compact and loose spongiosa of periosteal and endochondral origin respectively, seem to rather especially illustrate variation along the diaphysis in taxa with similar microanatomical features. Our analysis also reveals that primary bone in all the ichthyosaur taxa sampled (to the possible exception of Mixosaurus) is spongy in origin, that cyclical growth is a common pattern among ichthyosaurs, and confirms the previous assumptions of high growth rates in ichthyosaurs. Conclusions/Significance The occurrence of two types of remodelling patterns along the diaphysis, characterized by bone mass decrease and increase respectively is described for the first time. It raises questions about the definition of the osseous microanatomical specializations bone mass increase and osteoporosis, notably based on the processes involved, and reveals the difficulty in determining the true occurrence of these osseous specializations in ichthyosaurs. [less ▲]

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See detailNew look at the (70,1-) baryon multiplet in the 1/N(c) expansion
Matagne, Nicolas; Stancu, Floarea ULg

in Nucl. Phys. (2008), A811

So far, the masses of excited states of mixed orbital symmetry and in particular those of nonstrange $[{\bf 70},1^-]$ baryons derived in the $1/N_c$ expansion were based on the separation of a system of ... [more ▼]

So far, the masses of excited states of mixed orbital symmetry and in particular those of nonstrange $[{\bf 70},1^-]$ baryons derived in the $1/N_c$ expansion were based on the separation of a system of $N_c$ quarks into a symmetric core and an excited quark. Here we avoid this separation and show that an advantage of this new approach is to substantially reduce the number of linearly independent operators entering the mass formula. A novelty is that the isospin-isospin term becomes as dominant in $\Delta$ as the spin-spin term in $N$ resonances. [less ▲]

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See detailNew look at the [70,1-] nonstrange and strange baryons in the 1/Nc expansion
Matagne, Nicolas ULg; Stancu, Floarea ULg

in AIP Conference Proceedings (2011), 1343

The masses of excited nonstrange and strange baryons belonging to the multiplet $[{\bf 70},1^-]$ are calculated in the $1/N_c$ expansion to order $1/N_c$ with a new method which allows to considerably ... [more ▼]

The masses of excited nonstrange and strange baryons belonging to the multiplet $[{\bf 70},1^-]$ are calculated in the $1/N_c$ expansion to order $1/N_c$ with a new method which allows to considerably reduce the number of linearly independent operators entering the mass formula. This study represents an extension to SU(6) of our work on nonstrange baryons, the framework of which was SU(4). [less ▲]

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See detailA new look to an old measurement.
Pierard, Luc ULg; Magne, Julien ULg

in Journal of the American College of Cardiology (2009), 54(21), 1969-70

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See detailA new low-cost and non-intrusive feet tracker
Pierard, Sébastien ULg; PHAN BA, Remy ULg; Van Droogenbroeck, Marc ULg et al

in Workshop on Circuits, Systems and Signal Processing (ProRISC) (2011, November)

Capturing gait is useful for many applications, including video-surveillance and medical purposes. The most common sensors used to capture gait suffer from significant drawbacks. We have therefore ... [more ▼]

Capturing gait is useful for many applications, including video-surveillance and medical purposes. The most common sensors used to capture gait suffer from significant drawbacks. We have therefore designed a new low-cost and nonintrusive system to capture gait. Our system is able to track the feet on the horizontal plane in both the stance and the swing phases by combining measures of several range laser scanners. The number of sensors can be adjusted according to the target application specifications. The first issue addressed in this work is the calibration: we have to know the precise location of the sensors in a plane, and their orientations. The second issue addressed is how to calculate feet coordinates from the distance profiles given by the sensors. Our method has proven to be robust and precise to measure gait abnormalities in various medical conditions, especially neurological diseases (with a focus on multiple sclerosis). [less ▲]

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See detailA new Lower Cretaceous ichthyosaur from Russia reveals skull shape conservatism within Ophthalmosaurinae
Fischer, Valentin ULg; Arkhangelsky, Maxim; Uspensky, Gleb et al

in Geological Magazine (2014), 151(1), 60-70

Ophthalmosaurinae is a recently recognized clade of derived ichthyosaurs (marine reptiles) ranging from the Bajocian (Middle Jurassic) to the late Albian (late Early Cretaceous). Whereas the Middle-Late ... [more ▼]

Ophthalmosaurinae is a recently recognized clade of derived ichthyosaurs (marine reptiles) ranging from the Bajocian (Middle Jurassic) to the late Albian (late Early Cretaceous). Whereas the Middle-Late Jurassic ophthalmosaurine Ophthalmosaurus is often regarded as a hyperspecialized deep diver, very little is known about the anatomy, evolutionary history, and ecology of Cretaceous ophthalmosaurines because of the scarcity of the fossils and the lack of well-preserved skull material. Here, we describe the skull of a new basal ophthalmosaurine ichthyosaur, Leninia stellans gen. et sp. nov., from the lower Aptian of western Russia, and compare the ocular characteristics of ophthalmosaurids. Leninia is recovered as a basal ophthalmosaurine; it possesses unique traits such as star-shaped frontal–parietal sutures as well as features previously thought to be unique to Ophthalmosaurus such as a supratemporal–stapes contact. A large sclerotic aperture – significantly bigger than in platypterygiine ophthalmosaurids and similar to that of the largest-eyed modern animals (giant and colossal squids) – and reduced dentition appear widespread within ophthalmosaurines. This conservatism suggests ophthalmosaurine ophthalmosaurids occupied similar ecological niche(s) throughout their long evolutionary history. [less ▲]

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See detailNew magnetic field measurements of beta Cephei stars and slowly pulsating B stars
Hubrig, Swetlana; Briquet, Maryline ULg; De Cat, P. et al

in IAU Symposium (2009, April 01)

We present the results of the continuation of our magnetic survey with FORS 1 at the VLT of a sample of B-type stars consisting of confirmed or candidate β Cephei stars and Slowly Pulsating B stars ... [more ▼]

We present the results of the continuation of our magnetic survey with FORS 1 at the VLT of a sample of B-type stars consisting of confirmed or candidate β Cephei stars and Slowly Pulsating B stars. Roughly one third of the studied β Cephei stars have detected magnetic fields. The fraction of magnetic Slowly Pulsating B and candidate Slowly Pulsating B stars is found to be higher, up to 50%. We find that the domains of magnetic and non-magnetic pulsating stars in the H-R diagram largely overlap, and no clear picture emerges as to the possible evolution of the magnetic field across the main sequence. [less ▲]

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See detailNew magnetic field measurements of beta Cephei stars and slowly pulsating B stars
Hubrig, S.; Briquet, Maryline ULg; De Cat, P. et al

in Astronomische Nachrichten (2009), 330

We present the results of the continuation of our magnetic survey with FORS 1 at the VLT of a sample of B-type stars consisting of confirmed or candidate β Cephei stars and Slowly Pulsating B (hereafter ... [more ▼]

We present the results of the continuation of our magnetic survey with FORS 1 at the VLT of a sample of B-type stars consisting of confirmed or candidate β Cephei stars and Slowly Pulsating B (hereafter SPB) stars, along with a small number of normal B-type stars. A weak mean longitudinal magnetic field of the order of a few hundred Gauss was detected in three β Cephei stars and two stars suspected to be β Cephei stars, in five SPB stars and eight stars suspected to be SPB stars. Additionally, a longitudinal magnetic field at a level larger than 3Ï has been diagnosed in two normal B-type stars, the nitrogen-rich early B-type star HD 52089 and in the B5 IV star HD 153716. Roughly one third of β Cephei stars have detected magnetic fields: Out of 13 β Cephei stars studied to date with FORS 1, four stars possess weak magnetic fields, and out of the sample of six suspected β Cephei stars two show a weak magnetic field. The fraction of magnetic SPBs and candidate SPBs is found to be higher: Roughly half of the 34 SPB stars have been found to be magnetic and among the 16 candidate SPBs eight stars possess magnetic fields. In an attempt to understand why only a fraction of pulsating stars exhibit magnetic fields, we studied the position of magnetic and non-magnetic pulsating stars in the H-R diagram. We find that their domains in the H-R diagram largely overlap, and no clear picture emerges as to the possible evolution of the magnetic field across the main sequence. It is possible that stronger fields tend to be found in stars with lower pulsating frequencies and smaller pulsating amplitudes. A somewhat similar trend is found if we consider a correlation between the field strength and the v sin i-values, i.e. stronger magnetic fields tend to be found in more slowly rotating stars. Based on observations obtained at the European Southern Observatory, Paranal, Chile (ESO programmes 078.D-0140(A), 078.D-0330(A), 079.D-0241(A), and 080.D-0383(A)). [less ▲]

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See detailNew MALDI-Mass Spectrometry Imaging Procedures to Highlight Potential Proteic And Lipidic Biomarkers in Ovarian Cancer
Mériaux, Céline; Franck, Julien; Longuespée, Rémi ULg et al

Poster (2010, September)

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See detailA new map of the lava flow field of Nyamulagira (D.R. Congo) from satellite imagery
Smets, Benoît; Wauthier, Christelle ULg; d'Oreye, N.

in Journal of African Earth Sciences (2010)

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See detailA new Mars ionosphere/airglow Model between 60 and 500 km altitude
Witasse, Oliver; Blelly, P.; Lilensten, Jean et al

in Proceedings of the Workshop “Mars Atmosphere Modelling and Observations” (2003)

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See detailNew mass spectrometry based methodology to sequence a whole snake venom
Echterbille, Julien ULg; Boulanger, Madeleine; Degueldre, Michel ULg et al

Poster (2014, February 10)

Animal venoms are complex chemical cocktails, comprising wide ranges of biologically active reticulated peptides that target with high selectivity and efficacy varieties of membrane receptors. Assuming ... [more ▼]

Animal venoms are complex chemical cocktails, comprising wide ranges of biologically active reticulated peptides that target with high selectivity and efficacy varieties of membrane receptors. Assuming the fact that each of the 170,000 venomous species reported can produce more than 250 bioactive toxins, at least 40,000,000 bioactive peptides and proteins may be discovered. Among the four described species of mambas, Eastern Jameson’s mamba (Dendroaspis jamesonii kaimosae) venom is the less characterized since only 9 peptides are referenced in database. This work aims at developing a new strategy devoted to the deep analysis of animal venoms. Our approach consists in a first separation of the venom using cation exchange chromatography. Each primary fraction is then purified a second time by classical RP-HPLC. A total of 328 fractions, containing amongst 1 and 4 toxins, are finally collected. MALDI-MS analysis of each fraction is done in order (1) to obtain information about masses and (2) to obtain sequences of toxins thanks to MALDI-In Source Decay (ISD) dissociation coupled with on MALDI target plate reduction of the peptides. ISD has already been demonstrated efficient for toxin sequencing, and especially when using 1,5-DAN as reducing matrix. ISD yields to sequences that cover more than 50% of peptide sequences by series of singly charged c-type ions. Thanks to this methodology, we were able to obtain 85% of satisfactory results i.e. spectra giving quite long tags of amino acids (up to 20 residues). As a way to validate our method, a tag coming from ISD spectrum interpretation has found a match in database for an Eastern Jameson’s mamba toxin. The global sequence has then been obtained by extrapolation on the ISD spectrum. Since ISD spectra are simpler than classical MS/MS spectra, automation of spectra interpretation, difficult with other fragmentation techniques (CID, ETD…), is implementable. In the near future, sequences obtained with this approach will be used to direct tests of biological activity through sequence homologies with already known ligands for different kinds of membrane receptors. [less ▲]

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See detailThe new Mayo clinic equation for estimating glomerular filtration rate
Delanaye, Pierre ULg; Krzesinski, Jean-Marie ULg

in Annals of Internal Medicine (2005), 142(8), 679-680

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See detailNew measures of the quality and of the reliability of fits applied to forward hadronic data at t = 0
Cudell, Jean-René ULg; Kang, Kyungsik; Ezhela, V. V. et al

in H.M. Fried; Gabellini, Y.; Muller, B. (Eds.) NON - PERTURBATIVE QCD (2001)

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See detailA new mechanism of upwelling generated filaments based on potential vorticity balance
Troupin, Charles ULg; Mason, Evan; Beckers, Jean-Marie ULg et al

Poster (2009, April 19)

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See detailA new mechanism of upwelling generated filaments based on potential vorticity balance
Troupin, Charles ULg; Mason, Evan; Beckers, Jean-Marie ULg et al

Conference (2009, April 27)

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See detailNew mesh generation developments in GMSH
Remacle, Jean-François; Johnen, Amaury ULg; Lambrechts, Jonathan et al

in Actes du 11e Colloque National en Calcul des Structures (CSMA 2013), Giens, France (2013)

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See detailNew method for 3D reconstruction of the human cranial vault from CT-scan data
Laurent, Cédric ULg; JOLIVET, Erwan; HODEL, Jérôme et al

in Medical Engineering & Physics (2011), 33

This study presents a new method for the 3D reconstruction of the human cranial vault from routine Computed Tomography (CT) data. The reconstruction method was based on the conceptualization of the shape ... [more ▼]

This study presents a new method for the 3D reconstruction of the human cranial vault from routine Computed Tomography (CT) data. The reconstruction method was based on the conceptualization of the shape of the cranial vault with a parametric description. An initialization was first realized with the identification of anatomical landmarks and contours on Digitally Reconstructed Radiographs (DRR) in order to obtain a pre-personalized reconstruction. Then an optimization of the reconstruction was performed to segment the internal and external surfaces of the cranial vault for thickness computation. The method was validated by comparing final reconstructions issued from our approach and from a manual sliceby- slice segmentation method on ten CT-scans. Errors were comparable to the CT image resolution, and less than 2 min were dedicated to the operatordependant marking step. The reconstruction of internal and external surfaces of the cranial vault allows quantifying and visualizing of thickness throughout the cranial vault. This thickness mapping is useful for clinical purposes as additional pre-surgical information. Moreover, this study constitutes a first step in the personalized characterization of skull resistance directly from routine exams. [less ▲]

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See detailNew method for a two-step hydrolysis and chromatographic analysis of pectin neutral sugar chains
Garna, H.; Mabon, N.; Wathelet, Bernard ULg et al

in Journal of Agricultural and Food Chemistry (2004), 52(15), 4652-4659

A new method for the determination of the main neutral sugars in pectin has been developed. The sample preparation involves a mild chemical attack followed by an enzymatic hydrolysis. The completeness and ... [more ▼]

A new method for the determination of the main neutral sugars in pectin has been developed. The sample preparation involves a mild chemical attack followed by an enzymatic hydrolysis. The completeness and nondestructive character of the method are demonstrated by comparison of the results obtained with different acids such as H2SO4, HCI, and trifluoroacetic acid (TFA) at different concentrations (2, 1, or 0.2 M) at two temperatures (80 or 100 degreesC). The chemical hydrolysis of pectin neutral sugar chains with strong acid (1 or 2 M) and high temperature (100 degreesC) shows that the liberation of the pectin sugars is not realized at the same rate for each sugar. Different optimum conditions are thus obtained. However, the chemical pectin hydrolysis with 0.2 M TFA at 80 degreesC is characterized by the liberation of pectin neutral sugar side chains without any degradation within 72 h of hydrolysis. Under these conditions, the liberation of some pectin sugars, essentially galactose, glucose, and rhamnose, was not complete. An enzymatic hydrolysis is necessary to obtain a complete release of all the sugars. The combination of the two treatments, a chemical hydrolysis realized with diluted acid (0.2 M) for 72 h at low temperature (80 degreesC) on one hand and an enzymatic hydrolysis on the other hand, allow a total liberation of pectin sugars. The quantitative analysis of the carbohydrates is realized with accuracy, high selectivity, and sensitivity with high-performance anion-exchange chromatography with pulsed-amperometric detection. The sugars can be analyzed without any derivatization with a limit of quantification of 0.1 mM. [less ▲]

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