Browsing
     by title


0-9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

or enter first few letters:   
OK
Full Text
Peer Reviewed
See detailAnalysis of lipid profile in lipid storage myopathy
Aguennouz, M.; Beccaria, M.; Purcaro, Giorgia ULiege et al

in Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences (2016), 1029-1030

Lipid dysmetabolism disease is a condition in which lipids are stored abnormally in organs and tissues throughout the body, causing muscle weakness (myopathy). Usually, the diagnosis of this disease and ... [more ▼]

Lipid dysmetabolism disease is a condition in which lipids are stored abnormally in organs and tissues throughout the body, causing muscle weakness (myopathy). Usually, the diagnosis of this disease and its characterization goes through dosage of Acyl CoA in plasma accompanied with evidence of droplets of intra-fibrils lipids in the patient muscle biopsy. However, to understand the pathophysiological mechanisms of lipid storage diseases, it is useful to identify the nature of lipids deposited in muscle fiber. In this work fatty acids and triglycerides profile of lipid accumulated in the muscle of people suffering from myopathies syndromes was characterized. In particular, the analyses were carried out on the muscle biopsy of people afflicted by lipid storage myopathy, such as multiple acyl-coenzyme A dehydrogenase deficiency, and neutral lipid storage disease with myopathy, and by the intramitochondrial lipid storage dysfunctions, such as deficiencies of carnitine palmitoyltransferase II enzyme. A single step extraction and derivatization procedure was applied to analyze fatty acids from muscle tissues by gas chromatography with a flame ionization detector and with an electronic impact mass spectrometer. Triglycerides, extracted by using n-hexane, were analyzed by high performance liquid chromatography coupled to mass spectrometer equipped with an atmospheric pressure chemical ionization interface. The most representative fatty acids in all samples were: C16:0 in the 13–24% range, C18:1n9 in the 20–52% range, and C18:2n6 in the 10–25% range. These fatty acids were part of the most representative triglycerides in all samples. The data obtained was statistically elaborated performing a principal component analysis. A satisfactory discrimination was obtained among the different diseases. Using component 1 vs component 3 a 43.3% of total variance was explained. Such results suggest the important role that lipid profile characterization can have in supporting a correct diagnosis. © 2016 Elsevier B.V. [less ▲]

Detailed reference viewed: 20 (2 ULiège)
See detailAnalysis of liquid flow distribution in a trickle bed reactor
Toye, Dominique ULiege; Marchot, Pierre ULiege; Crine, Michel ULiege et al

in Frontiers in Industrial Process Tomography (1995)

Detailed reference viewed: 13 (0 ULiège)
See detailAnalysis of liquid flow distribution in trickle bed reactor using computer assisted tomography
Toye, Dominique ULiege; Marchot, Pierre ULiege; Crine, Michel ULiege et al

in Beck, M. S.; Hoyle, B. S.; Morris, M. A. (Eds.) et al Process tomography - 1995 - Implementation for industrial processes (1995)

Detailed reference viewed: 28 (2 ULiège)
Peer Reviewed
See detailAnalysis of Liquid Flow Distribution in Trickling Flow Reactor Using Computer-Assisted X-Ray Tomography
Toye, Dominique ULiege; Marchot, Pierre ULiege; Crine, Michel ULiege et al

in Chemical Engineering Research and Design (1995), 73(A3), 258-262

In this paper, we propose a new experimental technique, based on X-ray tomography, allowing the analysis of the gas-liquid-solid phase distribution in trickling flow reactors. Tomography refers to the ... [more ▼]

In this paper, we propose a new experimental technique, based on X-ray tomography, allowing the analysis of the gas-liquid-solid phase distribution in trickling flow reactors. Tomography refers to the cross-sectional imaging of an object from data collected by illuminating this object from many directions. The experimental set-up allows the scanning of transverse sections of rather large columns: up to 0.8 m diameter and 2 m height can be irradiated. Experiments were carried out both without and with liquid flow. In the absence of liquid, the reconstructed images give a view of the non-uniformity of the solid phase distribution. The images obtained are very complex because they result from the superposition of several distributions with different Spatial scales. We show the existence of a first spatial scale which allows us to separate properties belonging to the individual packing elements from those belonging to the bed scale. When liquid is flowing through the packed bed X-ray scans give a clear picture of the distribution of the liquid phase saturation, despite the very low liquid film thickness. Average values of this liquid phase saturation are determined and confronted with a partial wetting model. [less ▲]

Detailed reference viewed: 42 (1 ULiège)
Full Text
Peer Reviewed
See detailAnalysis of Liquid-Flooded Compression Using a Scroll Compressor
Bell, Ian; Lemort, Vincent ULiege; Braun, Jim et al

(2008, July)

One possible means of decreasing the work of compression of a scroll gas compressor is by injecting, or flooding, high specific heat liquid into the inlet gas stream of the compressor. The high specific ... [more ▼]

One possible means of decreasing the work of compression of a scroll gas compressor is by injecting, or flooding, high specific heat liquid into the inlet gas stream of the compressor. The high specific heat liquid can then absorb the heat of compression of the gas and offer the possibility of a reduction in the net power of the compressor. The particular application of interest for this flooded-compression technology is the Liquid-Flooded Ericsson cycle as proposed by Hugenroth et al. (2007), a gas refrigeration cycle. Adequate performance of the Ericsson cycle is contingent on designing scroll compressors that can efficiently compress high heat of compression gases. A detailed model of the flooded scroll compressor has been constructed which allows prediction of the compressor performance over a wide range of operating conditions. The detailed flooded scroll compressor model has been validated with experimental data, for which good agreement was found. [less ▲]

Detailed reference viewed: 110 (3 ULiège)
Full Text
Peer Reviewed
See detailAnalysis of liquid-flooded expansion using a scroll expander
Lemort, Vincent ULiege; Bell, Ian; Groll, Eckhard et al

(2008, July)

This paper presents the development and the experimental validation of a model of a scroll expander integrated into a Liquid Flooded Ericsson Cooler (LFEC) as proposed by Hugenroth (2007). This system ... [more ▼]

This paper presents the development and the experimental validation of a model of a scroll expander integrated into a Liquid Flooded Ericsson Cooler (LFEC) as proposed by Hugenroth (2007). This system uses liquid flooding of the compressor and the expander to approach isothermal compression and expansion processes. A detailed model of the flooded scroll expander has been constructed which allows prediction of its performance over a wide range of operating conditions. This model is validated with experimental data collected on a prototype of a Liquid Flooded Ericsson Cooler. A parametric study is finally conducted for investigating the performances of the expander under different design changes, such as the shape of the tip of the scroll and the leakage gap size. [less ▲]

Detailed reference viewed: 101 (3 ULiège)
Full Text
Peer Reviewed
See detailAnalysis of living tert-butyl methacrylate oligoanions in tetrahydrofuran by NMR spectroscopy, viscosity and light scattering
Zune, Catherine; Dubois, Philippe; Grandjean, Jean ULiege et al

in Macromolecular Chemistry and Physics (1999), 200(3), 562-573

Previous kinetic studies concluded on the aggregation of the anionic chain ends of living tert-butyl methacrylate oligomers [PtBMA-, Li+] in THF at low temperature. This aggregation has been confirmed by ... [more ▼]

Previous kinetic studies concluded on the aggregation of the anionic chain ends of living tert-butyl methacrylate oligomers [PtBMA-, Li+] in THF at low temperature. This aggregation has been confirmed by viscosimetry, light scattering and gradient field NMR techniques in a range of temperature from 253 K to 298 K. These techniques have been systematically used for the analysis of both the living oligomers and the same chains recovered after hydrolysis of the anionic end groups. The structure of the growing anionic species was analyzed by means of 13C and 7Li NMR spectroscopy. 13C NMR required the selective labeling of the last monomer units by 13C atoms. [less ▲]

Detailed reference viewed: 57 (8 ULiège)
Full Text
See detailAnalysis of longitudinal data for selection and management
Gengler, Nicolas ULiege; Mayeres, Patrick

in Book of Abstracts of the 53rd Annual Meeting of the European Association for Animal Production (2002, September)

Until recently the description of dynamic biological processes was done using static models even if those biological processes such as lactation or growth provided us with longitudinal data. A classical ... [more ▼]

Until recently the description of dynamic biological processes was done using static models even if those biological processes such as lactation or growth provided us with longitudinal data. A classical example was the use of lactational milk yields even if individual test-days describing the underlying lactation curves were available. Similarly for growth, weights were corrected phenotypically to fit into categories like weaning or yearling weights. Several recent developments stimulated the research on alternative methods describing the evolution of the mean and the variances of continuos dynamic biological processes. These developments were especially the extension of repeatability models towards random regressions and the development of the (co)variance function approach, but the development of better computers allowing the storage and the processing of a huge quantity of data. Despite this the analysis of certain types of longitudinal data as test-day yields in large populations and/or international settings is still a major challenge. But a very important aspect of the analysis of longitudinal data is often forgotten: they give us other information than the one classically extracted from genetic evaluation systems. In fact, the detailed modeling of dynamic biological processes provides opportunities for the development of advanced management tools. This may have a large influence on the way genetic evaluation systems may evolve in the future, making them integrated systems for the management and selection of animals. [less ▲]

Detailed reference viewed: 28 (5 ULiège)
Full Text
See detailAnalysis of longitudinal imaging data
Guillaume, Bryan ULiege

Speech/Talk (2012)

Detailed reference viewed: 19 (1 ULiège)
Full Text
Peer Reviewed
See detailAnalysis of luminosity distributions and shape parameters of strong gravitational lensing elliptical galaxies
Biernaux, Judith ULiege; Magain, Pierre ULiege; Sluse, Dominique ULiege et al

in Astronomy and Astrophysics (2016), 585

Context. The luminosity profiles of galaxies acting as strong gravitational lenses can be tricky to study. Indeed, strong gravitational lensing images display several lensed components, both point-like ... [more ▼]

Context. The luminosity profiles of galaxies acting as strong gravitational lenses can be tricky to study. Indeed, strong gravitational lensing images display several lensed components, both point-like and diffuse, around the lensing galaxy. Those objects restrain the study of the galaxy luminosity to its inner parts. Therefore, the usual fitting methods perform rather badly on such images. Previous studies of strong lenses luminosity profiles using such codes and various PSF-determining methods have resulted in somewhat discrepant results. Aims. The present work aims at investigating the causes of those discrepancies, as well as at designing more robust techniques to study the morphology of early-type lensing galaxies, with the ability to subtract lensed signal from their luminosity profiles. Methods. Each shape parameter, namely, the position angle, ellipticity and half-light radius of the galaxy, are determined as independently from each other as possible. The half-light radius measurement method is based on the computation of isophotes. Its robustness regarding various specific aspects of gravitational lensing image processing is analysed and tested versus that of a widely used fitting code, GALFIT. Those techniques are then applied on a sample of systems from the CASTLES database. Results. Simulations show that, when restricted to small, inner parts of the lensing galaxy, the technique presented here is more robust than GALFIT. It gives unbiased results, while GALFIT leads to an overestimation of the half-light radius that can reach about 10%, depending, among others, on the SNR. It is therefore better-suited than GALFIT for gravitational lensing images. It is also able to study lensing galaxies that are not much larger than the PSF, as opposed to GALFIT. New values for the half-light radius of the objects in our sample are presented and compared to previous works. [less ▲]

Detailed reference viewed: 46 (20 ULiège)
Full Text
Peer Reviewed
See detailAnalysis of mainstream tobacco smoke by SPME-GC×GC-TOFMS
Brokl, Michal ULiege; Bishop, L; Wright, C et al

Poster (2013, May)

Detailed reference viewed: 47 (3 ULiège)
Full Text
Peer Reviewed
See detailAnalysis of mainstream tobacco smoke particulate phase using comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry
Brokl, Michal ULiege; Bishop, L; Wright, C et al

in Journal of Separation Science (2013), 31

In tobacco research, the comparison of different tobacco blends as well as the puffdependent <br />behaviour of cigarettes is a matter of particular interest. For the investigation <br />of smoke ... [more ▼]

In tobacco research, the comparison of different tobacco blends as well as the puffdependent <br />behaviour of cigarettes is a matter of particular interest. For the investigation <br />of smoke characteristics, GC6GC offers different ways for data analysis, <br />namely, compound target analysis, automated peak-based compound classification <br />and comprehensive pixel-based data analysis. This study will show the application <br />as well as the pros and cons of these types of data analysis for very complex matrices <br />like cigarette particulate matter. In addition, new aspects about the recently discovered <br />puff-dependent behaviour of compounds in cigarette smoke will be presented. <br />Automated peak-based compound classification including mass spectrometric pattern <br />recognition is used for the classification of tobacco particulate matter samples <br />and the puff-dependent investigation of different compound classes. This compound <br />group specific analysis is further reinforced by applying an even more comprehensive <br />pixel-based analysis. This kind of analysis is used to generate fingerprints of <br />different types of cigarettes. The combination of fast feature reduction methods like <br />analysis of variance (ANOVA) and t-test with multivariate feature transformation <br />methods like partial least squares discriminate analysis (PLSDA) for feature selection <br />provides a powerful tool for a detailed inspection of different types of cigarettes. [less ▲]

Detailed reference viewed: 74 (16 ULiège)
Full Text
See detailAnalysis of Martian nightglow and aurora
Stiepen, Arnaud ULiege

Conference (2015, March)

Detailed reference viewed: 26 (2 ULiège)
See detailAnalysis of mass movements affecting the region of Constantine
Draidia, Salah ULiege; Havenith, Hans-Balder ULiege; Benabbas, C.

in EGU General Assembly Conference Abstracts (2014)

Abstract: Mass movements are a very frequent phenomenon in the North-Eastern Algeria, causing a lot of damages among the population and on the infrastructures and representing the most important geohazard ... [more ▼]

Abstract: Mass movements are a very frequent phenomenon in the North-Eastern Algeria, causing a lot of damages among the population and on the infrastructures and representing the most important geohazard. This paper presents some results of the analysis of slope instabilities in many places in the region and especially along the East-West highway. The work show many types of failures characterized by a high degree of heterogeneity. It is clear that the landslides in this area are very complex, in the most cases a combination of ... [less ▲]

Detailed reference viewed: 17 (1 ULiège)
Full Text
Peer Reviewed
See detailAnalysis of MERCATOR data - Part I: variable B stars
De Cat, P.; Briquet, Maryline ULiege; Aerts, C. et al

in Communications in Asteroseismology (2006), 147

We re-classified 31 variable B stars which were observed more than 50 times in the Geneva photometric system with the p7 photometer attached to the MERCATOR telescope (La Palma) during its first 3 years ... [more ▼]

We re-classified 31 variable B stars which were observed more than 50 times in the Geneva photometric system with the p7 photometer attached to the MERCATOR telescope (La Palma) during its first 3 years of scientific observations. HD 89688 is a possible beta Cephei/slowly pulsating B star hybrid and the main mode of the COROT target HD 180642 shows non-linear effects. The Maia candidates are re-classified as either ellipsoidal variables or spotted stars. Although the mode identification is still ongoing, all the well-identified modes so far have l <= 2. [less ▲]

Detailed reference viewed: 15 (2 ULiège)
Peer Reviewed
See detailAnalysis of Migration in a Multi-Risk Context: Case of Bujumbura/Burundi
Nibigira, Léonidas ULiege; Ozer, Pierre ULiege; Havenith, Hans-Balder ULiege

in MAIER, ROBIN; REVELL, MARK (Eds.) THE AMERICAN ASSOCIATION OF GEOGRAPHERS, 2017 Annual Meeting, April 5 - 9, 2017 Boston, Massachusetts / PROGRAM (2017, April 08)

Human mobility affects land use and human density distribution. Unfortunately, this rarely takes into account the real and potential changes induced by hazards on the natural systems. Thus, migration and ... [more ▼]

Human mobility affects land use and human density distribution. Unfortunately, this rarely takes into account the real and potential changes induced by hazards on the natural systems. Thus, migration and natural hazards should be constantly analyzed through cross-sectional and global studies to reduce disastrous consequences resulting from their mutual interactions. In a multi-risk and demographic sprawl context, the study focused on the cross-analysis of human density and natural hazards in Bujumbura. The results show that migration of people should ideally be guided by knowledge of the area's sensitivity to natural hazards, taking into account other parameters such as hazards susceptibility maps and production opportunities. While the migration of people toward overcrowded centers constitutes a big challenge, it is an important asset when it concerns areas in need of manpower. It also allows the balance in relieving saturated areas, reducing human pressure on the environment. Therefore, there is a need that policymakers comply with those aspects, finding the right balance for a better situation. [less ▲]

Detailed reference viewed: 95 (20 ULiège)