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See detailValorisation des sous-produits de la graine de Jatropha curcas L. en production de poulets au Sénégal
Nesseim, Thierry ULiege

Doctoral thesis (2017)

This study evaluated the effects of Jatropha curcas kernel meal incorporated in poultry feed in Senegal. All experimentations were conducted in the experimental station of the National Superior School of ... [more ▼]

This study evaluated the effects of Jatropha curcas kernel meal incorporated in poultry feed in Senegal. All experimentations were conducted in the experimental station of the National Superior School of Agriculture (ENSA) of Thies University (Senegal). In the same way, all chemical analyses were performed in the feed science laboratory of the Department of Animal Production of ENSA. The first part of this study was a description of toxic and anti-nutritional compounds present in J. curcas seed meal, which most important are phorbol esters, characteristics of Euphorbiaceae, known for its inflammatory effects, and curcin, a toxalbumin which manifested by an irritant action. Other compounds, also present, interfere more or less with digestive process in animals. Different treatments were applied, with different levels of success, to reduce or eliminate these toxic and anti-nutritional compounds for the valuation of this meal in animal feed. A particular emphasis was placed on the biological treatment, not only for a significant reduction of these compounds but also to improve the nutritional quality of the meal. The second part of this work has focused on the study of the effect of the J. curcas kernel meal obtained by chemical de-oiling, incorporated in corn at 4, 8, and 12% and distributed to broiler chickens at the end their growth phase to assess their feed intake, their daily weight gain and diet digestibility. For all diets, feed intake was inversely influenced by the incorporation on the jatropha kernel meal, leading a weight gain decrease in animals that received the largest amounts of jatropha despite the absence of toxicity signs and mortality. Similarly, the apparent digestibility of each nutrient has been affected by the incorporation of jatropha kernel meal as well as the differential digestibility thereof. The low digestibility, especially protein was explained by the low availability of meal proteins incorporated corn, but also the presence of anti-nutritional and toxic factors still present in the diets used. The third part of this work has presented results of two experimentations conducted successively. The first one studied the effect of jatropha kernel meal obtained by a chemical de-oiling, incorporated in diets at 4 and 8%, on broiler chickens performance during growing/finishing. The second experimentation studied the effect of the same cake that was heat treated before incorporated in diets at 8%, on day-old broiler chicks’ performance. In one as the other experimentation, feed intake and daily weight gain were affected by the incorporation of jatropha kernel meal. It was the same for the total mortality rates recorded despite the absence of visible signs of toxicity. These experimentations confirmed other experimentations have shown that the de-oiling of jatropha kernel meal followed by heat treatment, even if it caused a significant reduction of anti-nutritional compounds, did not remove all the toxic factors that may even interfere with feed intake and weight gain of animals. These observations were not confirmed in the fourth part, which studied the effects of jatropha kernel meal obtained by chemical de-oiling, subject to heat treatment then biological treatment with Aspergillus niger and incorporated in diets at 8%, on day-old broiler chicks performance. Indeed, the feed intake, the weight gain as well as the viability of animals were not affected by the incorporation of jatropha. These successive studies were among the first which interested the same animal species at different levels of development based on a product whose nutritional quality is proven, but has toxic and anti-nutritional factors could not be completely eliminated despite different treatments applied. The application of heat treatment may have helped to reduce some anti-nutritional compounds (curcin and trypsin inhibitor) but without improve feed intake and weight gain. Considering the reaction of animals subjected to diet, biological and heat treatments may have reduced the toxicity of jatropha kernel meal, which has afected the feed intake of animals and thus the weight gain. This study showed that, despite its nutritional level, J. curcas kernel meal presented limitations in its use as a raw material that can integrate a ration for broilers in Senegal but hopes remain with biological treatments. [less ▲]

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See detailPrevenzione quaternaria, primum non nocere
Jamoulle, Marc ULiege

Conference (2017, September 28)

When presented in Durham during the 1995 WICC workshop, the concept of quaternary prevention, born in 1986, has attracted the consensus of the whole audience. In 2003 it has been discretely published in ... [more ▼]

When presented in Durham during the 1995 WICC workshop, the concept of quaternary prevention, born in 1986, has attracted the consensus of the whole audience. In 2003 it has been discretely published in the Wonca dictionary of general practice. Since this time, medicine has changed. The diffusion of knowledge and the sagacity of some researchers has shown that medicine could become dangerous for health. The concepts of overinformation, overdiagnosis, overtreatment and overscreening are now the bread and butter of numerous medical journals and the themes of numerous books and disputes throughout the world. Quaternary prevention encompasses all those domains and supersedes them by putting the relationships between patient and doctor at the center of the ethical reflection. WICC has been instrumental in the genesis and dissemination of the concept of quaternary prevention. This concept is now known and distributed worldwide under the acronym P4. Family physicians form interlinked P4 groups in various countries. It is the theme of many congresses and was propelled to the forefront of the recent Wonca Europe Congress. This concept could induce profound changes in the role of the family physician in health care. Moreover, the combination of the four definitions of prevention provided an amazing view of the activity of family physicians and could renew basic job description in GP / FM. [less ▲]

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See detailVitamine D et Vitamin D Binding protein
VRANKEN, Laura ULiege

Conference (2017, September 28)

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See detailLe Stress Oxydant: arnaque ou biologie d'avenir?
LE GOFF, Caroline ULiege

Conference (2017, September 28)

Detailed reference viewed: 24 (1 ULiège)
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See detailA mathematical model of respiration under protective ventilation and extracorporeal CO2 removal therapy
Habran, Simon ULiege; Desaive, Thomas ULiege; MORIMONT, Philippe ULiege et al

Conference (2017, September 27)

The aim of the present study is to build a mathematical model of the respiratory system connected to an extracorporeal CO2 removal device (ECCO2RD) to optimize the gas exchanges efficiency. The model must ... [more ▼]

The aim of the present study is to build a mathematical model of the respiratory system connected to an extracorporeal CO2 removal device (ECCO2RD) to optimize the gas exchanges efficiency. The model must be simple enough to provide rapid solutions and to estimate specific parameters from available clinical data. But it also must be complex enough to be able to simulate the respiratory system when protective ventilation is used and when this system is assisted by an ECCO2RD. [less ▲]

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See detailDevelopment of nuclear SNP markers for the timber tracking of the African tree species Sapelli, Entandrophragma cylindricum
Blanc-Jolivet, Céline; Kersten, Birgit; Bourland, Nils et al

in Conservation Genetics Resources (2017)

We describe the development of new nuclear SNP markers for the genetic timber tracking of the geographical origin of Sapelli, Entandrophragma cylindricum (Meliaceae). Restriction associated DNA sequencing ... [more ▼]

We describe the development of new nuclear SNP markers for the genetic timber tracking of the geographical origin of Sapelli, Entandrophragma cylindricum (Meliaceae). Restriction associated DNA sequencing (RADseq) of two reference individuals yielded 1131 putative SNPs. Among those, 131 were selected to design four MassARRAY multiplexes and screened at 178 individuals. Seventy-two loci were selected for further use in genetic tracking. [less ▲]

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See detailAbundance determination in massive stars: challenges for mixing processes
Cazorla, Constantin ULiege

Doctoral thesis (2017)

Massive stars, the most luminous stars, are the true “cosmic engines” of our Universe. They eject large quantity of material throughout their life, which strongly influences their evolutionary path as ... [more ▼]

Massive stars, the most luminous stars, are the true “cosmic engines” of our Universe. They eject large quantity of material throughout their life, which strongly influences their evolutionary path as well as their environment. An important feature of massive stars is their high rotational velocities that are either acquired at birth or due to the influence of a companion. Rotation is believed to transport nitrogen-rich and carbon/oxygen-poor material generated in the stellar core through the CNO cycle, to the surface. A way to test the e ciency of rotational mixing is to study the chemical composition at the surface of stars, in particular the fastest rotators. The incentive for this study was the discovery, in the context of the VLT- FLAMES Survey of Massive Stars, of fast rotators exhibiting an unenriched nitrogen composition at their surface, contrary to predictions from single-star evolutionary models including rotation. However, their multiplicity may a ect this conclusion, since both rotation and abundances can change as a result of binary interactions. In this work, we combined, for the first time, a detailed surface abundance analysis with a radial-velocity study to quantify the importance of binary e ects. This work was conducted for a sample of 40 bright, OB fast rotators in our Galaxy. Statistical tests and period-search techniques revealed that ≥ 40% of our targets whose multiplicity status can be probed, are binary or binary candidates. We derived the projected rotational velocity of our targets and model atmosphere codes were then used to derive stellar parameters and surface abundances of all sample stars. This abundance study revealed a correlation between the helium and nitrogen abundances of our targets, which is predicted by the rotational mixing theory. Finally, we compared our results to predictions of single-star evolutionary models. We found that 10 – 20% of our 40 targets exhibit no enhancement of the [N/O] abundance ratio, in line with results of the VLT-FLAMES Survey of Massive Stars. The properties of only half of our sample are explained by such models, and surprisingly we also uncovered a quite common large abundance of helium at the surface of our targets. Modifying the di usion coe cient in single-star models and models of non-rotating mergers did not reproduce simultaneously both the observed helium abundances and the [N/O] abundance ratios. Binary models considering a mass-transfer episode can, however, reproduce the [N/O] values of the majority of our targets and even the helium abundances of some of the most helium-enriched targets, but they cannot explain stars displaying little helium enrichment but high [N/O] values. In conclusion, we found that not every feature of massive stars can be explained by models, suggesting that they lack a physical ingredient and thus require further improvements. The second part of this thesis aimed at improving our knowledge of the X-ray emission of early B-type stars. We studied 11 such stars at high resolution thanks to two X-ray facilities, XMM-Newton and Chandra, doubling the number of B-stars analysed at high resolution. In many aspects, our study confirmed previous ones: early B-stars display rather narrow and unshifted lines arising from a warm (of typically 0.2 – 0.6 keV) plasma located at a few stellar radii over the stellar surface. We also found that abundances derived in the X-ray domain are in fair agreement with photospheric ones derived in the optical domain. Furthermore, most early B-stars are moderately bright X-ray emitters – though we also unexpectedly found that this X-ray emission varies, on short and/or long timescales, for half of our sample. A few stars display peculiar features: the presence of a very hot (1.6 – 4.4 keV) component and strong variations. These features suggest that the recorded X-ray emission may not be entirely linked to the B-stars, but could be contaminated by emission from a companion or an interaction with it. Indeed, in one case, HD 79351, a flare was detected, of a luminosity compatible with those from PMS stars, and which could be associated to its companion. Finally, the data used also led to the discovery of the second case of X-ray pulsations associated to beta Cephei activity. [less ▲]

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See detailHollow Nanoparticles for Low Cost, High Activity and Durability for the Oxygen Reduction Reaction for Fuel Cell Applications
Asset, Tristan ULiege

Doctoral thesis (2017)

This Ph.D. thesis investigates the mechanisms driving the formation, the enhanced activity for the oxygen reduction reaction (ORR) and the durability of porous hollow PtM/C nanoparticles (NPs) for proton ... [more ▼]

This Ph.D. thesis investigates the mechanisms driving the formation, the enhanced activity for the oxygen reduction reaction (ORR) and the durability of porous hollow PtM/C nanoparticles (NPs) for proton ex-change membrane fuel cell (PEMFC) applications. The formation and growth of the NPs, synthesized by a ‘one-pot’ process, were discussed in the light of microscopic, operando X-ray and electron-based tech-niques, unveiling the different intermediate steps of the synthesis. The synthe-sis process was extended to different non-noble metals (M = Ni, Co, Cu, Zn and Fe) and to different carbon supports. The enhanced activity for the ORR resulted from (i) the contraction of the lattice pa-rameter by the non-noble metal (the final NPs contains ca. 15 – 20 at. % of M), (ii) the open porosity and (iii) the density of structural defects at the surface of the NPs, which was semi-quantitativey estimated by COads stripping measurements and Rietveld analysis of wide-angle X-ray scattering patterns. The non-noble metal was found to be annealed (dissolved) faster than the structural defects during the accelerated stress tests. [less ▲]

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Peer Reviewed
See detailThe EP’s ‘European Standards’ Resolution in the wake of James Elliott Construction: carving ever more holes in Pandora’s Box?
Van Cleynenbreugel, Pieter ULiege; Demoulin, Iris ULiege

E-print/Working paper (2017)

This blogpost analyses a recent Parliamentary resolution against the background of the Court of Justice's James Elliott Construction judgment, dealing with the legal nature of harmonised technical ... [more ▼]

This blogpost analyses a recent Parliamentary resolution against the background of the Court of Justice's James Elliott Construction judgment, dealing with the legal nature of harmonised technical standards in EU free movement law. [less ▲]

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See detailConférence d'ouverture : La morale de 1964 : une écriture en débats
Cormann, Grégory ULiege; Bourgault, Jean

Conference (2017, September 22)

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See detailContraintes et stratégies d’amélioration de la filière maïs au Rwanda
Musabanganji, Edouard ULiege

Doctoral thesis (2017)

For more than a decade, Rwanda has adopted a series of policies and strategies aimed at economic development and the improvement of the living conditions of its predominantly agricultural population. In ... [more ▼]

For more than a decade, Rwanda has adopted a series of policies and strategies aimed at economic development and the improvement of the living conditions of its predominantly agricultural population. In agriculture, implementation of these strategies and related programs has been accompanied by a series of advances in the adoption of farming technologies and increasing agricultural production. However, the country's economy is still characterized by subsistence agriculture, and for the maize sector in particular, the country is continuously depending on imports to meet domestic demand, and maize processing plants always operate below their productive capacity. This research aims to examine the level of competitiveness of this sector in the current production and marketing conditions in order to identify existing constraints and formulate the strategies that can improve the level of economic performance of maize production and maize marketing system. The data used to study the economic performance of maize production come from close monitoring of maize production activities on a sample of 50 producers from five maize producers’ cooperatives selected in the districts of Huye, Rusizi, Gasabo, Burera and Bugesera during two growing seasons. They were supplemented by direct observation, interviews with targeted resource persons, and focus group discussions. The analysis was done using group analysis and appropriate statistical methods. The study of the maize marketing system used the 'Structure-Conduct-Performance' model with data collected from a sample of 150 producers and 17 assemblers selected in the districts of Burera, Bugesera and Huye, and 15 transporters, 5 wholesalers and 15 retailers selected at the national market of Kigali. The results revealed that for many producers, the yield is very low compared to theoretical expected yields, production costs are higher and exceed sales prices, gross margin and family labor income are negative, and the gross added value created by maize producers is not high even though it is positive. The analysis showed that the increase in the selling price positively influences the gross margin, added value and family labor income, and that the rational use of improved seeds, chemical fertilizers and soil conditioners improves the yield. This clearly shows that improving the selling price and rational use of inputs can significantly contribute to making maize production a more profitable and income-generating activity. The study also identified challenges that hamper the production process. These include non-availability of, and low access to inputs, inadequate technical support, limited financial resources and low access to formal agricultural credit, high marshlands rental fee, method of fixing the maize floor price and lack of mechanisms ensuring its use by potential buyers, the lack of storage infrastructure, and the unsustainability of inputs subsidies granted by the government. At the marketing level, the results revealed that several actors are involved in the marketing of maize. The study also revealed that maize imported from Uganda is sold on domestic market at lower prices than locally produced maize, which attests the increase in the cost of maize production in Rwanda compared to Uganda and the low level of competitiveness of the local maize compared to Ugandan maize. The improved status of feeder roads and the high level of access to price information by actors were highlighted among the technological innovations that helped improve the marketing system of foodstuffs in general and maize in particular, which was also evidenced by the level of integration observed between districts maize markets and the national market of Kigali. However, the lack of enough capital and low access to formal credit were noted as major constraints by most of the chain actors. In the light of all these results, it is clear that the production and marketing of maize are not done in good conditions at all levels. This in turn undermines the sector's ability to respond adequately to domestic demand, generate income for actors and integrate itself into both domestic and regional markets. Therefore, strategies aiming at scaling-up the maize production and marketing, and improving working conditions of the sector operators were recommended. These strategies include the implementation of actions to improve access to finance by farmers and other actors; making inputs avail and accessible; reorganizing the marketing system especially in terms of fixing and using the floor price; making available storage facilities where necessary; improving the monitoring, training and sensitization of maize producers on farming techniques and the use of improved technologies; and harmonizing the marshland rental fee at national level. [less ▲]

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See detailIntroduction (master in aerospace engineering)
Grodent, Denis ULiege

Learning material (2017)

Introduction

Detailed reference viewed: 33 (11 ULiège)
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See detailTowards a covering aerospray method for quantitative analyses of pharmaceutical tablets using surface-enhanced Raman chemical imaging (SER-CI)
Cailletaud, Johan ULiege; De Bleye, Charlotte ULiege; Dumont, Elodie ULiege et al

Conference (2017, September 22)

In recent years, the use of SERS-CI in pharmaceutical sciences has increased in order to study the distribution of low-dose compounds in solid dosage forms [1]. This technique allows to improve the ... [more ▼]

In recent years, the use of SERS-CI in pharmaceutical sciences has increased in order to study the distribution of low-dose compounds in solid dosage forms [1]. This technique allows to improve the sensitivity of conventional Raman microscopy and to reduce significantly the image acquisition time by exalting the signal information. However, the applications of SERS-CI in the pharmaceutical field remain limited, especially due to the difficulty of obtaining a homogeneous deposit of metallic nanoparticles on the sample surface. Generally, the covering method used on the tablet is a drop casting deposition due to its simplicity and rapidity of implementation. Despite the colloidal solution deposit is not fully controlled. The inhomogeneous covering is the result of the “coffee-ring” effect that concentrates the nanoparticles at the edges of the droplet [2]. This implies remarkable variations of the SERS analyte signal’s intensity at different places. For a more reproducible and homogeneous coating, an aerospray method using a homemade apparatus was developed (Figure 1). The device is composed with a pair of coaxial tubes, the colloidal solution is pulled through the inner tube from a syringe pump and the outer tube is connected to a source of high pressure gas. Nitrogen, used as a nebulizing gas, creates a flow of small droplets of nanoparticles that are nearly dry when they hit the sample surface. The aerospray device is easy to implement and the entire surface of the tablet is covered by the SERS substrate in a homogeneous way. By using this covering method, the potential of SERS-CI is improved and making it a suitable technique for quantitative analyses of low drug concentrations or impurities in pharmaceutical tablets. [less ▲]

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See detailLes interactions enseignant/enfants comme soutien au développement langagier des enfants en classe maternelle
Leroy, Sandrine ULiege; Bergeron-Morin, Lisandre ULiege; Desmottes, Lise ULiege et al

in Les entretiens de Bichat : les entretiens d'orthophonie 2017 : Les pathologies du langage chez l'enfant de moins de 6 ans: facteurs de risque (FR), facteurs de protection (FP) (2017, September 22)

L'école maternelle constitue un contexte privilégié pour soutenir le développement du langage et de la communication des enfants. La qualité des interactions entre l’enseignant et les enfants de sa classe ... [more ▼]

L'école maternelle constitue un contexte privilégié pour soutenir le développement du langage et de la communication des enfants. La qualité des interactions entre l’enseignant et les enfants de sa classe est reconnue comme étant l’aspect le plus déterminant de la qualité éducative, notamment en ce qui concerne le développement langagier. Cet article a pour objectif de faire un survol de la littérature sur le développement du langage des enfants en contexte préscolaire, sur le rôle que peut y jouer l’enseignant, ce qui ouvre des perspectives quant aux modalités de développement professionnel des enseignants en maternelle. [less ▲]

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See detailTowards the development of a dual mode fluorescence/SERS dopamine aptasensor
Dumont, Elodie ULiege; De Bleye, Charlotte ULiege; Cailletaud, Johan ULiege et al

Poster (2017, September 21)

This work was dedicated to the development of a dual mode fluorescence and surface-enhanced Raman scattering (SERS) dopamine aptasensor. The preparation of the aptasensor was first optimised. Thereafter ... [more ▼]

This work was dedicated to the development of a dual mode fluorescence and surface-enhanced Raman scattering (SERS) dopamine aptasensor. The preparation of the aptasensor was first optimised. Thereafter, calibration curves were realised by means of fluorescence quenching and SERS. Finally, the specificity of both methods was tested. [less ▲]

Detailed reference viewed: 35 (7 ULiège)
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See detailQuelques pistes pour relancer la foresterie sociale et la participation en Afrique centrale
Vermeulen, Cédric ULiege

Conference (2017, September 21)

Detailed reference viewed: 54 (11 ULiège)
See detailHealing effect of controlled anti-electromigration on conventional and high-Tc superconducting nanowires
Baumans, Xavier ULiege; Lombardo, Joseph ULiege; Brisbois, Jérémy ULiege et al

Conference (2017, September 21)

At the present time, electron beam lithography (EBL) is considered as the reference technique for nanoscale patterning. However, making nanostructures below the sub-10 nm scale is still challenging due to ... [more ▼]

At the present time, electron beam lithography (EBL) is considered as the reference technique for nanoscale patterning. However, making nanostructures below the sub-10 nm scale is still challenging due to broadening effects (forward electron scattering, backscattering, electrostatic charging…), and requires strong investment in terms of cost for state-of-the-art EBL systems. In this sense, alternative methods are continuously explored in order to make such nanofabrication easily reachable. A promising approach consists of inducing atomic diffusion by a large current density. This phenomenon, called electromigration (EM), and well known since the 60’s as a failure mechanism in metallic interconnections [1], still attracts interests from scientists and engineers for its great potential for fabrication of microstructures and for its reversibility character [2, 3]. In this work, we show that the combination of electromigration and anti-electromigration allows the precise tuning of superconducting properties of Al nanoconstrictions and we also observe the reversibility of electromigration failure for this material (see Fig. 1). The same process has been applied on Nb, leading to a more irreversible process, and La2 xCexCuO4. For the latter material, we show that selective migration of oxygen atoms and the consequent doping modification induces a transition from a superconducting state to an insulating state in a reversible way [4]. We also discussed the possibility to enhance the electromigration technique by replacing the complex feedback control by a technique of electropulsing. These researches have direct practical impact as a method to explore the dependence of the characteristic parameters on the exact oxygen content and pave the way for a reversible control of local properties of nanowires. [less ▲]

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See detailLa communication scientifique directe vers un public élargi. L’actualité sociale traitée par des chercheurs dans les carnets de recherche Hypothèses
Mayeur, Ingrid ULiege

in Revue Française des Sciences de l'Information et de la Communication (2017), 11

This contribution aims to examine a social mediation allowed by the open access, which is imparting knowledge in Social Sciences and Humanities (thereafter SSH) through a broader public. I will consider ... [more ▼]

This contribution aims to examine a social mediation allowed by the open access, which is imparting knowledge in Social Sciences and Humanities (thereafter SSH) through a broader public. I will consider the platform OpenEdition (and specifically Hypothèses that concerns academic blogging) as a ground of investigation. The matter will be a specific way to impart knowledge, which is the treatment of the actuality by researchers through their reading grids in SSH. In the corpus analysis, I will stress the appropriation modes of the device by the researchers that comment the actuality, the expected audience and practices that the texts suggest, and the discursive processes that are used. I also will question how “direct” such scientific communication is on an academic blog published on a platform in open access. [less ▲]

Detailed reference viewed: 63 (0 ULiège)