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See detailDevelopment of a translation stage for in situ noninvasive analysis and high-resolution imaging
Strivay, David ULg; Clar, Mathieu ULg; Rakkaa, Saïd ULg et al

in Applied Physics A : Materials Science & Processing (2016), 122

Non-invasive imaging techniques and analytical instrumentation for cultural heritage object studies have undergone a tremendous development over the last years. Many new miniature and/or handheld systems ... [more ▼]

Non-invasive imaging techniques and analytical instrumentation for cultural heritage object studies have undergone a tremendous development over the last years. Many new miniature and/or handheld systems have been developed and optimized. Nonetheless, these instruments are usually used with a tripod or a manual position system. This is very time consuming when performing point analysis or 2D scanning of a surface. The Centre Européen d’Archéométrie has built a translation system made of pluggable rails of 1 m long with a maximum length and height of 3 m. Three motors embedded in the system allow the platform to be moved along these axis, toward and backward from the sample. The rails hold a displacement system, providing a continuous movement. Any position can be reached with a reproducibility of 0.1 mm. The displacements are controlled by an Ethernet connection through a laptop computer running a multiplatform custom-made software written in JAVA. This software allows a complete control over the positioning using a simple, unique, and concise interface. Automatic scanning can be performed over a large surface of 3 m on 3 m. The Ethernet wires provide also the power for the different motors and, if necessary, the detection head. The platform has been originally designed for a XRF detection head (with its full power alimentation) but now can accommodate many different systems like IR reflectography, digital camera, hyperspectral camera, and Raman probes. The positioning system can be modified to combine the acquisition software of the imaging or analytical techniques and the positioning software. [less ▲]

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See detailDevelopment of a transmission model of Murid herpesvirus 4
François, Sylvie ULg

Doctoral thesis (2012)

Gammaherpesviruses are the archetype of persistent viruses that have been identified in a series of animals ranging from mice to man. To date the study of transmission of these viruses in natural ... [more ▼]

Gammaherpesviruses are the archetype of persistent viruses that have been identified in a series of animals ranging from mice to man. To date the study of transmission of these viruses in natural condition has been limited by the fact that no experimental transmission model exists. Establishment and characterization of a model of transmission are therefore critical points to evaluate strategies of interference with the epidemiological cycle of gammaherpesviruses. We are studying Murid herpesvirus 4 (MuHV-4) which has originally been isolated from naturally infected bank voles (Myodes glareolus). Although serological data indicate that closely related strains are present in wood mice (Apodemus sylvaticus) and domestic mice (Mus musculus), no experimental transmission of MuHV-4 has been demonstrated in laboratory mice, the classically used in vivo model. The objective of this work was therefore to fill this gap. In a first study, we performed a comparative characterization of the infection by MuHV-4 in mice and bank voles. Our results showed that the infectious process, the pathology and the latency establishment are similar in the two species, even if replication is quantitatively lower in bank voles than in mice. It therefore appeared that, Mus musculus represents a suitable host for studying gammaherpesvirus pathogenesis with MuHV-4. These results have been published in Journal of General Virology (J Gen Virol. 2010 Oct;91(Pt 10):2553-63). In a second study, thanks to in vivo imaging, we have been able to observe, for the first time, transmission of MuHV-4 in mice. We firstly showed that MuHV-4 reexcretion occurs in the genital tract of female mice at a period by which latency is considered as established. Ex vivo imaging, histology and PCR allowed us to demonstrate the presence of viral genomes in vaginal tissues and to localize viral replication at the external border of the vagina. We also demonstrated the transient and repetitive presence of infectious viruses in the vaginal cavity. Secondly, we demonstrated the implication of sexual steroid hormones in this re-excretion process. Indeed, we analyzed the infection of untreated mice, ovariectomized mice and ovariectomized mice complemented with estrogens and/or progesterone. These analyses revealed a positive role of estrogens in the observed re-excretion. Finally, based on these results, we tested MuHV-4 transmission in mice by creating different epidemiological conditions. In the conditions tested, vertical transmission did not occur, nor did horizontal transmission between individuals of the same gender. In contrast, we were able to observe sexual transmission to naïve males by serology, in vivo imaging and quantitative PCR. In conclusion, this work has on one hand demonstrated the quality of mice as an in vivo model for MuHV-4 studies and, on the other, it has shown for the first time the existence of re-excretion and sexual transmission of MuHV-4 amongst laboratory mice. The results of this work should therefore have implications for the study of gammaherpesviruses, but also more generally for the study of sexually transmissible infections. [less ▲]

Detailed reference viewed: 118 (30 ULg)
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See detailDevelopment of a two-color picosecond optical parametric oscillator, pumped by a Nd:YAG laser mode locked using a nonlinear mirror, for doubly-resonant sum frequency generation spectroscopy
Mani, A. A.; Dreesen, Laurent ULg; Humbert, C. et al

in Surface Science (2002), 502-503

We step up a doubly-resonant sum frequency generation (DR-SFG) spectrometer based on the use of an all-solid-state flash-lamp-pumped Nd:YAG laser that synchronously pumps two parametric oscillators ... [more ▼]

We step up a doubly-resonant sum frequency generation (DR-SFG) spectrometer based on the use of an all-solid-state flash-lamp-pumped Nd:YAG laser that synchronously pumps two parametric oscillators. Pulses as short as 12 ps FWHM are generated by mode locking a Nd:YAG oscillator using a frequency doubling nonlinear mirror combined with a two-photon absorber. The available pump power is shared between a LiNbO3/AgGaS2 optical parametric oscillator (OPO), tunable from 3800 to 1100cm-1 and a BBO OPO tunable from 410 to 2600 nm. Spectral resolution and pulse are 2 and 3 cm-1 in the infrared and visible spectral ranges, respectively. First DR-SFG spectra of self-assembled monolayers on Au are presented. [less ▲]

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See detailDevelopment of a unified model for flow-material interaction applied to porous charring ablators
Coheur, Joffrey ULg; Schrooyen, Pierre; Turchi, Alessandro et al

Conference (2017, June)

Detailed reference viewed: 26 (11 ULg)
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See detailDevelopment of a universal microarray based on the ligation detection reaction and 16S rRNA gene polymorphism to target diversity of cyanobacteria
Castiglioni, Bianca; Rizzi, Ermann; Frosini, Andrea et al

in Applied and Environmental Microbiology (2004), 70(12), 7161-7172

The cyanobacteria are photosynthetic prokaryotes of significant ecological and biotechnological interest, since they strongly contribute to primary production and are a rich source of bioactive compounds ... [more ▼]

The cyanobacteria are photosynthetic prokaryotes of significant ecological and biotechnological interest, since they strongly contribute to primary production and are a rich source of bioactive compounds. In eutrophic fresh and brackish waters, their mass occurrences (water blooms) are often toxic and constitute a high potential risk for human health. Therefore, rapid and reliable identification of cyanobacterial species in complex environmental samples is important. Here we describe the development and validation of a microarray for the identification of cyanobacteria in aquatic environments. Our approach is based on the use of a ligation detection reaction coupled to a universal array. Probes were designed for detecting 19 cyanobacterial groups including Anabaena/Aphanizomenon, Calothrix, Cylindrospermopsis, Cylindrospermum, Gloeothece, halotolerants, Leptolyngbya, Palau Lyngbya, Microcystis, Nodularia, Nostoc, Planktothrix, Antarctic Phormidium, Prochlorococcus, Spirulina, Synechococcus, Synechocystis, Trichodesmium, and Woronichinia. These groups were identified based on an alignment of over 300 cyanobacterial 16S rRNA sequences. For validation of the microarrays, 95 samples (24 axenic strains from culture collections, 27 isolated strains, and 44 cloned fragments recovered from environmental samples) were tested. The results demonstrated a high discriminative power and sensitivity to 1 fmol of the PCR-amplified 16S rRNA gene. Accurate identification of target strains was also achieved with unbalanced mixes of PCR amplicons from different cyanobacteria and an environmental sample. Our universal array method shows great potential for rapid and reliable identification of cyanobacteria. It can be easily adapted to future development and could thus be applied both in research and environmental monitoring. [less ▲]

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See detailDevelopment of a version of GeoPEARL for the Walloon region of Belgium
Bah, Boubacar Billo ULg; Vanclooster, Marnik; Oger, Robert ULg

Scientific conference (2009, November)

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See detailDevelopment Of A Visual Method To Quantify The Gossypol Content In Cotton Seeds
Benbouza, H.; Lognay, Georges ULg; Palm, Rodolphe ULg et al

in Crop Science (2002), 42(6), 1937-1942

Detailed reference viewed: 45 (6 ULg)
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See detailDevelopment of a waste heat recovery orc prototype using an oil-free scroll expander
Declaye, Sébastien ULg; Quoilin, Sylvain ULg; Lemort, Vincent ULg

Conference (2011, September 22)

The world is facing a historical increase in energy demand and energy consumption. As consequence the conventional fossil fuels are depleting faster with an inherent pollution causing severe damages to ... [more ▼]

The world is facing a historical increase in energy demand and energy consumption. As consequence the conventional fossil fuels are depleting faster with an inherent pollution causing severe damages to our environment. Renewable energy sources are considered as a solution to both environmental issue and energy demand. At the same time a lot of waste heat is witnessed in processes in industries. Our objective is to contribute to the development of ORC systems, that appear to us as a good solution to recover this wasted heat. In such waste heat applications, depending on the heat source flow rate and temperature, electrical power output can be as low as a few kilowatts. In this power range, there is no cost effective expansion machine available on the market. On existing prototypes, expansion devices are usually retrofitted volumetric compressors originally designed for refrigeration or air compression applications. Air compressors have the advantage to handle higher inlet temperature but tightness is often an issue in ORC application since the fluids used have a non negligible environmental impact. This paper presents the development of a small-scale WHR ORC unit at the Thermodynamic Laboratory of the University of Liège: the prototype uses a scroll expander, plate heat exchangers, a diaphragm piston pump and a liquid receiver. This system was tested with different working fluids (R123, R245fa and HFE7000) and a thermal efficiency close to 8% was obtained for a net output power of about 2 kWe. The specificity of the proposed prototype is the absence of lubrication: in order to avoid oil circulation in the ORC loop, an oil-free scroll expander is developed. This expander is originally an air scroll compressor that was modified using a magnetic coupling to ensure tightness. The experimental results highlight the good efficiency of the device, despite a relatively high internal leakage due to absence of lubrication. The necessity of using magnetic coupling is also justified by comparing the experimental results with previous ones obtained using mechanical sealing. [less ▲]

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See detailDevelopment of adenocarcinoma in chronic fistula in Crohn's disease
Laurent, Stanislas; Barbeaux, A.; Detroz, Bernard ULg et al

in Acta Gastro-Enterologica Belgica (2005), 68(1, Jan-Mar), 98-100

The authors report the case of a 55 yr-old woman suffering from Crohn's disease since 31 years with stricture and fistulas developed in the ileocolic junction and anorectal portion. Long-standing ... [more ▼]

The authors report the case of a 55 yr-old woman suffering from Crohn's disease since 31 years with stricture and fistulas developed in the ileocolic junction and anorectal portion. Long-standing anorectal fistulas and stricture led to adenocarcinoma and finally fistulisation in the vagina. Diagnosis was made by perineal examination with biopsies under general anaesthesia. Treatment was first posterior pelvectomy with resection of the anterior wall of vagina. Secondarily, radiochemotherapy was administrated. The authors discuss the incidence and risk factors of carcinoma in Crohn's disease with chronic fistulas. [less ▲]

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See detailDevelopment of Advanced Driver Assistance Systems by means of the traffic flow simulation tool PELOPS with HiL-functionalities
Christen, Fréderic ULg; Benmimoun, A.; Breuer, K. et al

in Berechnung und Simulation im Fahrzeugbau (2004, September 29)

During the last years a rapid increase of traffic volume in association with limited road space could be observed. This led to a raising load of the driver while achieving his driving tasks. Therefore so ... [more ▼]

During the last years a rapid increase of traffic volume in association with limited road space could be observed. This led to a raising load of the driver while achieving his driving tasks. Therefore so called Advanced Driver Assistance Systems (ADAS) are under development in recent years with an upward tendency. Such systems will relieve the driver and improve safety on the road in the future. A rising number of computed-aided-simulation becomes important for the development and evaluation of such systems. Developing ADAS makes a specific demand on the simulation environment. ADAS interact strongly with their traffic environment. Therefore the simulation has to cover both, a detailed model of the ego vehicle and an adequate representation of the traffic environment. The traffic flow simulation program PELOPS meets these requirements. The newly implemented extension of PELOPS with techniques of Software- and Hardware-in-the-Loop-simulation (SiL- and HiL-simulation) allows system developers a fast functional check and an assessment of new ADAS. External software can be linked to PELOPS via Ethernet-based network communication, which has already been realised for the widely used development tool MATLAB/Simulink. Besides the Ethernet interface PELOPS-HiL (PHIL) gives the developer two other possibilities for providing a HIL-environment: a serial interface which can be used for a connection to a dSpace development platform and a CAN data bus interface. The following article describes by means of chosen examples how flexible the PHIL-simulation can be adapted to a development task and which results can be obtained. [less ▲]

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See detailDevelopment of advanced models for transition to turbulence in hypersonic flows and prediction of transition under uncertainties
Serino, Gennaro ULg; Terrapon, Vincent ULg; Magin, Thierry et al

in Serino, Gennaro (Ed.) Review of the VKI Doctoral Research 2012-2013 (2013, March)

Detailed reference viewed: 166 (10 ULg)
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See detailDevelopment of alternative methods to control aphids (Hemiptera: Aphididae): from wheat-pea intercropping to the use of semiochemical dispensers
Chevalier Mendes Lopes, Thomas ULg

Doctoral thesis (2016)

Increasing the sustainability of food production is a major challenge in today’s agriculture. Several practices can be implemented to reduce the use of external inputs such as agrochemicals. In terms of ... [more ▼]

Increasing the sustainability of food production is a major challenge in today’s agriculture. Several practices can be implemented to reduce the use of external inputs such as agrochemicals. In terms of insect pest control, the concept of integrated pest management (IPM) has been exploited to minimize the application of chemical insecticides. The idea is to limit pest infestations while promoting their control by natural enemies. One possibility is to increase within crops plant diversity namely by intercropping. Semiochemical dispensers may also be used to attracted natural enemies into crops. Focusing on wheat (Triticum aestivum Linnaeus), several types of intercropping can be practiced with variable effects on pests and natural enemies. This PhD thesis focuses on the potential of wheat-pea (Pisum sativum Linnaeus) intercropping as a way to reduce aphid (Hemiptera: Aphididae) infestations. We firstly assessed the diversity of aphid and their parasitoid species in wheat and pea fields using yellow pan traps and in situ observations on plants. Whether several aphid species were trapped, only Sitobion avenae (Fabricius), Metopolophium dirhodum (Walker), Rhopalosiphum padi (Linnaeus) and Acyrthosiphon pisum (Harris) were found on wheat tillers and pea plants respectively. Regarding parasitoids, some species can use wheat and/or pea aphids as hosts. The first Belgian parasitoid species checklist was established, with the inclusion of four Aphidiinae (Hymenoptera: Braconidae) and three Aphelinus (Hymenoptera: Aphelinidae) species as new records. In terms of abundance, we firstly compared the effect of two types of wheat-pea intercropping (mixed and alternate strip cropping) on aphids and their natural enemies with pure stands of both crops. The mixture was particularly efficient to reduce pea aphid populations, while alternate strips were more suitable for the control of wheat aphids. However, natural enemies were more abundant in the pure stands, showing that additional methods may be needed to attract them more efficiently. One possibility is the use of semiochemicals dispensers. In another field study, we combined a wheat-pea mixture with methyl salicylate (MeSA) dispensers. This substance was selected due to its known attractive effect towards some aphid beneficials. Even though adult hoverflies (Diptera: Syrphidae) were not particularly attracted by the mixture combined with MeSA dispensers, they may have stimulated their oviposition behaviour. Also, mummified aphids were significantly more abundant in the pure stand of pea compared with the mixture (with and without MeSA). However, parasitism rates did not differ significantly between treatments. Beneficial effects of wheat-pea intercropping were clearly demonstrated for aphid control. Other agronomic aspects make this practice particularly interesting in low-input farming systems. These are discussed, along the limitations related to the use semiochemicals in field conditions. Perspectives for further research works are also proposed. [less ▲]

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See detailDevelopment of alumina xerogel catalysts for biogas cleaning
Claude, Vincent ULg; Heinrichs, Benoît ULg; Toye, Dominique ULg et al

Poster (2014)

This poster resume the synthesis and characterizations of Ni/y-Al2O3 catalysts for the reforming of tars during the bio-syngas purification. The effect of an additionnal organosilane (EDAS) and a ... [more ▼]

This poster resume the synthesis and characterizations of Ni/y-Al2O3 catalysts for the reforming of tars during the bio-syngas purification. The effect of an additionnal organosilane (EDAS) and a surfactant (stearic acid) on the size,the dispersion and the sinterability of the nickel nanoparticles have been investigated. [less ▲]

Detailed reference viewed: 92 (14 ULg)
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See detailDevelopment of an absolute quantification method targeting growth hormone biomarkers using liquid chromatography coupled to isotope dilution mass spectrometry.
Kirsch, Stéphanie ULg; Widart, Joëlle ULg; Louette, Joel et al

in Journal of Chromatography. A (2007), 1153(1-2), 300-6

A method to perform absolute quantification of two biomarkers (IGF-1 and IGFBP-3) of growth hormone abuse has been developed. Isotope dilution is used with synthetically labelled peptides as internal ... [more ▼]

A method to perform absolute quantification of two biomarkers (IGF-1 and IGFBP-3) of growth hormone abuse has been developed. Isotope dilution is used with synthetically labelled peptides as internal standards. Peptide selection and multiple reaction monitoring design are discussed. A simple sample preparation based on the reduction and alkylation of cysteine residues followed by tryptic digestion provides a sufficient digestion of proteins. Serum samples fortified with increasing amounts of target proteins are analysed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) on a triple quadrupole mass spectrometer. Specificity is ensured by the selection of sequences with no homology in BLAST, as well as retention time deviation check, and ion ratio monitoring. Linearity is studied in terms of calibration curves. These curves for IGFBP-3 and IGF-1 are generated with mean slopes of 0.055 and 0.065, intercepts of 0.107 and -0.011, and with coefficients of correlation of 0.95 and 0.98, respectively. These curves result from the addition of proteins to the serum. Risks of variations related to potential matrix effects are therefore reduced, as well as probable variations related to the digestion steps. The working concentration ranges are 4-10 ng/microl for IGFBP-3 and 2-8 ng/microl for IGF-1. Preliminary data regarding repeatability show that relative standard deviations (RSDs) range between 13 and 32% for IGFBP-3 and between 7 and 29% for IGF-1. [less ▲]

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See detailDevelopment of an active H maser: first results
Mandache, Cipriana ULg; Léonard, D.; Bastin, Thierry ULg

Conference (2009)

Detailed reference viewed: 52 (13 ULg)
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See detailDevelopment of an algorithm for using PINP to monitor treatment of patients with teriparatide
Eastell, R.; Krege, J. H.; Chen, P. Q. et al

in Current Medical Research & Opinion (2006), 22(1), 61-66

Introduction: Teriparatide effects are mediated via the preferential stimulation of osteoblastic activity over osteoclastic activity. Amino-terminal propeptide of type I procollagen (PINP) is an indicator ... [more ▼]

Introduction: Teriparatide effects are mediated via the preferential stimulation of osteoblastic activity over osteoclastic activity. Amino-terminal propeptide of type I procollagen (PINP) is an indicator of osteoblastic activity. Objective: Develop an algorithm using PINP as an aid in the management of patients with postmenopausal osteoporosis treated with teriparatide. Research design and methods: For inclusion in this post-hoc analysis, trials had to be investigations of teriparatide 20 mu g/day in postmenopausal women with osteoporosis having measurements of PINP at 3 months and bone mineral density (BMD) at 12 months. Signal-to-noise ratio was calculated for a series of markers of bone turnover in the Fracture Prevention Trial. An algorithm was developed to monitor patients treated with teriparatide using PINP. Results:Three trials met inclusion criteria and included the Fracture Prevention, Forteo-Alendronate Comparator and Anabolic After Antiresorptive trials. PINP had the highest signal-to-noise ratio of all bone-turnover markers. Positive PINP responses defined as increases > 10 mu g/L were observed in 77-97% of teriparatide- and in 6% of placebo-treated patients after 3 months of study drug. Mean lumbar spine BMD increases after 12 months of teriparatide in patients having PINP changes > 10 mu g/L ranged from 8.3% to 9.5% and in patients with PINP changes <= 10 mu g/L ranged from 5.9% to 7.6%. In the algorithm, PINP is measured at baseline and after 1-3 months of therapy. Patients with PINP increases > 10 mu g/L are given a positive message. Patients with PINP increases <= 10 mu g/L are assessed for adherence, teriparatide administration and storage techniques, and for the presence of medical conditions that might limit their therapeutic response, and these issues are addressed as appropriate. Patients without these issues and with PINP increases <= 10 mu g/L should be given a neutral message because BMD may significantly increase with continued therapy. Conclusions: The PINP algorithm provides information regarding the anabolic response to teriparatide therapy and has the potential to identify patients requiring help with issues of adherence, injection technique, teriparatide storage, and medical problems limiting therapeutic responsiveness to teriparatide treatment, Data assessing the relationship of changes in PINP to fracture risk reduction are not available. We recommend physicians audit the use of the algorithm in practice so that improvements can be made. [less ▲]

Detailed reference viewed: 113 (1 ULg)