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See detailMagnetic susceptibility evolution on Paleozoic sedimentary settings, a clue for past paleoenvironments
Da Silva, Anne-Christine ULg; Pas, Damien ULg; Mabille, Cédric et al

in Suttner; Kido; Piller (Eds.) et al Mid Paleozoic climate and biodiversity. IGCP-596 opening meeting. Abstract Volume (2011)

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See detailLes déterminants de l'adhésion aux mutuelles de santé en Afrique subsaharienne : un inventaire des travaux empiriques
Defourny, Jacques ULg; Failon, Julie ULg

in Mondes en Développement (2011), 153

En Afrique Subsaharienne, les taux d’adhésion aux mutuelles de santé restent généralement à des niveaux très faibles. Cet article vise à synthétiser les résultats des enquêtes déjà réalisées pour ... [more ▼]

En Afrique Subsaharienne, les taux d’adhésion aux mutuelles de santé restent généralement à des niveaux très faibles. Cet article vise à synthétiser les résultats des enquêtes déjà réalisées pour identifier les facteurs qui influencent la décision d’adhérer ou non à ces mutuelles. Au-delà des différences méthodologiques entre ces travaux, notre synthèse fait ressortir deux facteurs majeurs qui étaient plutôt attendus (la capacité financière des populations et la qualité des soins) et les resitue dans une perspective plus large. Elle permet également d’identifier quelques autres paramètres qui semblent aussi jouer un rôle significatif même si les convergences entre les enquêtes sont moins nettes. [less ▲]

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See detailAnalyse des pigments des dessins pariétaux de la grotte Chauvet à Vallon-Pont-d'Arc
Laval, Eric; Salomon, Hélène ULg; Vignaud, Colette et al

Conference (2011)

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See detailProblèmes du bilinguisme dans l'Antiquité gréco-romaine
Rochette, Bruno ULg

in Genet, Jean-Philippe (Ed.) Langues et histoire. Actes du colloque de l'Ecole doctorale d'histoire de Paris 1 INHA, 20 et 21 octobre 2006 (2011)

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See detailDiscovering the lichen diversity of a remote tropical island: working list of species collected on Reunion (Mascarene archipelago, Indian Ocean)
Sérusiaux, Emmanuël ULg; van den Boom, Pieter P. G.; Brand, Maarten et al

in Herzogia (2011), 24(2), 325-349

463 lichen taxa are reported from the island of Reunion (Mascarene archipelago) in the Indian Ocean. This report is based on extensive collections recently made by the authors or hosted in B and LG. A ... [more ▼]

463 lichen taxa are reported from the island of Reunion (Mascarene archipelago) in the Indian Ocean. This report is based on extensive collections recently made by the authors or hosted in B and LG. A total of c. 600 species is estimated for the number of lichenized fungi present on the island; although this is a low figure for a varied tropi- cal area, this is plausible due to its small size and remoteness. The significance of the lichen diversity of the island lays in its endemics, which need further study for a reliable assessment, and in the occurrence of a poorly known southern hemisphere element (“austral” species). The discovery of the following in Reunion is of special interest as it considerably enlarges their distribution range: Anzia corallophora, Caloplaca caesiosorediata, Coccocarpia delicatula, Fuscopannaria praetermissa, Gomphillus morchelloides, G. pedersenii, Gyalideopsis bispora, Heterodermia koyana, Hypotrachyna evansii, Lithogyalideopsis zeylandica, Lobaria asperula, Megaloblastenia marginiflexa var. dimota, Menegazzia capitata, Myeloconis erumpens and Pannaria squamulosa. [less ▲]

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See detailThe impact of a minimum pension on old age poverty and its budgetary cost. Evidence from Latin America
Pestieau, Pierre ULg; Dethier, Jean-Jacques; Rabia, Ali

in Revista de Economía del Rosario (2011), 14(2), 37-65

This paper examines the impact on old age poverty and the fiscal cost of universal minimum old age pensions in Latin America using recent household survey data for 18 countries. Alleviating old age ... [more ▼]

This paper examines the impact on old age poverty and the fiscal cost of universal minimum old age pensions in Latin America using recent household survey data for 18 countries. Alleviating old age poverty requires different approach from other age groups and a minimum pension is likely to be the only alternative available. First we measure old age poverty rates for all countries. Second we discuss the design of minimum pensions schemes, means-tested or not, as well as the disincentive effects that they are expected to have on the economic and social behavior of households including labor supply, saving and family solidarity. Third we use the household surveys to simulate the fiscal cost and the impact on poverty rates of alternative minimum pensionschemes in the 18 countries. We show that a universal minimum pension would substantially reduce poverty among the elderly except in Argentina, Brazil, Chile and Uruguay where minimum pension systems already exist and poverty rates are low. Such schemes have much to be commended in terms of incentives, spillover effects and administrative simplicity but have a high fiscal cost. The latter is a function of the age at which benefits are awarded, the prevailing longevity, the generosity of benefits, the efficacy ofmeans testing, and naturally the fiscal capacity of the country. [less ▲]

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See detailPresent and future climates of the Greenland ice sheet according to the IPCC AR4 models
Franco, Bruno ULg; Fettweis, Xavier ULg; Erpicum, Michel ULg et al

in Climate Dynamics (2011), 36

The atmosphere–ocean general circulation models (AOGCMs) used for the IPCC 4th Assessment Report (IPCC AR4) are evaluated for the Greenland ice sheet (GrIS) current climate modelling. The most suited ... [more ▼]

The atmosphere–ocean general circulation models (AOGCMs) used for the IPCC 4th Assessment Report (IPCC AR4) are evaluated for the Greenland ice sheet (GrIS) current climate modelling. The most suited AOGCMs for Greenland climate simulation are then selected on the basis of comparison between the 1970–1999 outputs of the Climate of the twentieth Century experiment (20C3M) and reanalyses (ECMWF, NCEP/NCAR). This comparison indicates that the representation quality of surface parameters such as temperature and precipitation are highly correlated to the atmospheric circulation (500 hPa geopotential height) and its interannual variability (North Atlantic oscillation). The outputs of the three most suitable AOGCMs for present-day climate simulation are then used to assess the changes estimated by three IPCC greenhouse gas emissions scenarios (SRES) over the GrIS for the 2070–2099 period. Future atmospheric circulation changes are projected to dampen the zonal flow, enhance the meridional fluxes and therefore provide additional heat and moisture to the GrIS, increasing temperature over the whole ice sheet and precipitation over its northeastern area. We also show that the GrIS surface mass balance anomalies from the SRES A1B scenario amount to −300 km3/year with respect to the 1970–1999 period, leading to a global sea-level rise of 5 cm by the end of the 21st century. This work can help to select the boundaries conditions for AOGCMs-based downscaled future projections. [less ▲]

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See detailPost-mortem examination and laboratory-based analysis for the diagnosis of bovine tuberculosis among dairy cattle in Ecuador
Proano-Perez, F.; Benitez-Ortiz, Washington; Desmecht, Daniel ULg et al

in Preventive Veterinary Medicine (2011), 101(1-2), 65-72

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See detail2D-Vertical Model for Free Surface Incompressible Flows: Validation and Applications
Detrembleur, Sylvain; Dewals, Benjamin ULg; Pirotton, Michel ULg

in Proc. 34th IAHR World Congress - Balance and Uncertainty (2011)

Efficient design of hydraulic structures such as weirs and bottom outlets requires a detailed description of the complex turbulent flows occurring on these structures. Compared to laboratory experiments ... [more ▼]

Efficient design of hydraulic structures such as weirs and bottom outlets requires a detailed description of the complex turbulent flows occurring on these structures. Compared to laboratory experiments, numerical modeling offers more flexibility and cost-effectiveness to test different designs. The non-hydrostatic 2D-vertical model presented here solves the RANS equations for incompressible flows in the vertical plane. It is based on the projection method for pressure-velocity coupling, while free surface tracking is conducted by means of the level set technique and Sussman’s velocity extension algorithm. It enables to predict accurately the flow pattern in the vertical plane and deals with multiple interfaces (jets, drops…). The solver has been validated for both steady and unsteady free surface flows, based on theoretical and experimental data. The paper will detail the application of the model to a pressurized flow and to a sloshing tank. [less ▲]

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See detailAtomic oxygen distributions in the Venus thermosphere: Comparisons between Venus Express observations and global model simulations
Brecht, A.; Bougher, S. W.; Gérard, Jean-Claude ULg et al

in Icarus: International Journal of Solar System Studies (2011)

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See detailConférences: les rencontres du CEA en 2010
Van Ruymbeke, Muriel ULg

Report (2011)

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See detailStructure-Guided Design of Cell Wall Biosynthesis Inhibitors That Overcome beta-Lactam Resistance in Staphylococcus aureus (MRSA).
Contreras-Martel, Carlos; Amoroso, Ana Maria ULg; Woon, Esther C.Y. et al

in ACS Chemical Biology (2011)

beta-Lactam antibiotics have long been a treatment of choice for bacterial infections since they bind irreversibly to Penicillin-Binding Proteins (PBPs), enzymes that are vital for cell wall biosynthesis ... [more ▼]

beta-Lactam antibiotics have long been a treatment of choice for bacterial infections since they bind irreversibly to Penicillin-Binding Proteins (PBPs), enzymes that are vital for cell wall biosynthesis. Many pathogens express drug-insensitive PBPs rendering beta-lactams ineffective, revealing a need for new types of PBP inhibitors active against resistant strains. We have identified alkyl boronic acids that are active against pathogens including methicillin-resistant S. aureus (MRSA). The crystal structures of PBP1b complexed to 11 different alkyl boronates demonstrate that in vivo efficacy correlates with the mode of inhibitor side chain binding. Staphylococcal membrane analyses reveal that the most potent alkyl boronate targets PBP1, an autolysis system regulator, and PBP2a, a low beta-lactam affinity enzyme. This work demonstrates the potential of boronate-based PBP inhibitors for circumventing beta-lactam resistance and opens avenues for the development of novel antibiotics that target Gram-positive pathogens. [less ▲]

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See detailAn extended thermodynamic model of transient heat conduction at sub-continuum scales
Lebon, Georgy ULg; Machrafi, Hatim ULg; Grmela, M. et al

in Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences (2011), 467

A thermodynamic description of transient heat conduction at small length and timescales is proposed. It is based on extended irreversible thermodynamics and the main feature of this formalism is to ... [more ▼]

A thermodynamic description of transient heat conduction at small length and timescales is proposed. It is based on extended irreversible thermodynamics and the main feature of this formalism is to elevate the heat flux vector to the status of independent variable at the same level as the classical variable, the temperature. The present model assumes the coexistence of two kinds of heat carriers: diffusive and ballistic phonons. The behaviour of the diffusive phonons is governed by a Cattaneo-type equation to take into account the high-frequency phenomena generally present at nanoscales. To include non-local effects that are dominant in nanostructures, it is assumed that the ballistic carriers are obeying a Guyer–Krumhansl relation. The model is applied to the problem of transient heat conduction through a thin nanofilm. The numerical results are compared with those provided by Fourier, Cattaneo and other recent models. [less ▲]

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See detailDensity functional theory beyond the linear regime: Validating an adiabatic local density approximation
Helbig, N.; Fuks, J. I.; Casula, M. et al

in Physical Review. A (2011), 83

We present a local density approximation (LDA) for one-dimensional (1D) systems interacting via the soft-Coulomb interaction based on quantum Monte Carlo calculations. Results for the ground-state ... [more ▼]

We present a local density approximation (LDA) for one-dimensional (1D) systems interacting via the soft-Coulomb interaction based on quantum Monte Carlo calculations. Results for the ground-state energies and ionization potentials of finite 1D systems show excellent agreement with exact calculations obtained by exploiting the mapping of an N-electron system in d dimensions onto a single electron in N×d dimensions, properly symmetrized by the Young diagrams. We conclude that 1D LDA is of the same quality as its three-dimensional (3D) counterpart, and we infer conclusions about 3D LDA. The linear and nonlinear time-dependent responses of 1D model systems using LDA, exact exchange, and the exact solution are investigated and show very good agreement in both cases, except for the well-known problem of missing double excitations. Consequently, the 3D LDA is expected to be of good quality beyond the linear response. In addition, the 1D LDA should prove useful in modeling the interaction of atoms with strong laser fields, where this specific 1D model is often used. [less ▲]

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See detailBronzer a tout crin ou se depigmenter avec acharnement: des modes d'addiction ethnique au gout du jour.
FRANCHIMONT, Claudine ULg; Henry, Frédéric ULg; PIERARD, Gérald ULg

in Revue Médicale de Liège (2011), 66(4), 191-4

Sun is at the origin of life and is responsible for death as well. In the past decades cutaneous melanoma has affected more and more young adults. In the White population, sun exposures and sunbeds are ... [more ▼]

Sun is at the origin of life and is responsible for death as well. In the past decades cutaneous melanoma has affected more and more young adults. In the White population, sun exposures and sunbeds are pointed out as the main culprits responsible for addictive behaviour. Preventive measures to be taken aim at avoiding the effects of ultraviolet light addiction. Sunlight exposure particularly in moderation is indeed beneficial through vitamin D3 synthesis and improved psychological wellbeing. Hence, we are facing the dilemma between too much and too little ultraviolet light exposure.In the Black population, the reverse situation is prevalent. It concerns skin depigmentation which may turn out to be a caricature in some subjects. [less ▲]

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See detailDeep Brain Stimulation : une nouvelle thérapie?
Thonnard, Marie ULg

in Schnakers, Caroline; Laureys, Steven (Eds.) Coma et état de conscience altérée (2011)

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See detailTRANSMISSION ROUTES OF NOROVIRUSES, EMERGING HUMAN PATHOGENS IN FOOD “NORISK”
Mathijs, E; Stals, A; Denayer, S et al

Book published by Belgian Science Policy (2011)

A. Context Noroviruses are pathogens causing gastroenteritis and infections result in typical symptoms such as abdominal cramps, fever, watery diarrhea and other symptoms such as headaches, chills and ... [more ▼]

A. Context Noroviruses are pathogens causing gastroenteritis and infections result in typical symptoms such as abdominal cramps, fever, watery diarrhea and other symptoms such as headaches, chills and general myalgias, which usually last for 2 to 3 days. The illness is self-limiting in most cases. The NV genus contains 5 genogroups whereby genogroup I and II (GI and GII) comprise most of the human infective NV genotypes. Bovine and murine NV are classified respectively in genogroup III (GIII) and V (GV), while porcine NV are also classified in GII. Human infective (mainly GI and GII) noroviruses (NV) have increasingly been recognized as a global major cause of acute non-bacterial gastroenteritis, but sensitive detection is only possible by molecular methods, due to the unavailability of a cultivation system. Development of these molecular methods showed that NV could be responsible for 60 % and 77 % of all gastroenteritis cases with known etiology in the USA and in Europe, respectively. The fraction of NV outbreaks caused by consumption of contaminated foods is estimated to be 10 to 20 %. Food products can be contaminated through 2 main transmission routes: either pre-harvest contamination, whereby mostly fresh produce and bivalve shellfish are involved. Shellfish are contaminated by cultivation in contaminated water, while fresh produce can by contaminated by use of contaminated irrigation water or (post-) harvest contamination often involving an infected food handler or food picker. A broad range of food products are related to the latter transmission route. Detection of NV in foods is more difficult because detection of NV present at very low levels on the foods should be possible due to the low infectious dose. Therefore, (genomic material of) NV has to be extracted from the foods and has to be detected subsequently by a molecular detection method. Furthermore, NVs are present in several animal species, raising important questions about zoonotic transmission and potential animal reservoir. B. Objectives 1. The NV RNA detection methodology: elaboration, optimization and evaluation of a real-time PCR format and determination of specificity, sensitivity and robustness. Two protocols will be developed. A real-time RT-PCR protocol directed to detection of the acknowledged GGI and GGII strains involved in outbreaks to be used in the frame of control and surveillance by food authorities and food business operators to verify their products and production process. Another real-time RT PCR protocol directed towards a wide diversity of NV genogroups (including newly reported animal associated NV) to be used for research purposes to establish transmission routes and document circulating strains in the environment. 2. The sample preparation method: to evaluate the effectiveness of several virus concentration / viral RNA extraction and purification protocols from a variety of food matrices in particular seafoods and with emphasis on elaboration of an appropriate extraction producedure in fresh produce/ready-to-eat foods. 3. The routine detection of NVs in food stuffs (seafoods and fresh products): to develop and implement a standard protocol with establishment of appropriate controls for rapid screening of foods for the presence of NVs in accordance with the guidelines for officially approved analysis and harmonization and to generate information on the prevalence of NV strains in foods at retail, products and production processes under the control of food business operators and the primary production. 4. Elucidation of transmission routes (zoonosis hypothesis) through molecular tracing, with a global view on NV strains circulating among human, animal and also in food. 5. The tracing of outbreaks: scenario for coupling clinical data from NV outbreaks to their foodborne cause and risk evaluation. 6. The development of a risk profile on NV present in the food chain and animal species (strain types circulating, potential animal reservoir, zoonose, definition and incidence in at risk foods, link to epidemiological information). 7. Tracing of the genetic evolution of NVs: genetic profiles and emerging of recombinants C. Conclusions Objective 1: A multiplex real-time RT-PCR assay for simultaneous detection of human GI and GII NV in clinical samples was designed, with the successful inclusion of MNV-1 as real-time PCR IAC. Evaluation of this multiplex assay showed a high concordance between the multiplex assay and the corresponding singleplex PCR assays. Specificity analysis of the multiplex assay by testing a NV RNA reference panel and clinical GI and GII NV samples showed that specific amplification of NV GI and GII was possible. In addition, no cross-amplification was observed when subjecting a collection of bovine NV and other (non-NV) enteric viruses to the multiplex assay. Finally, MNV-1 was successfully integrated as IAC, although a sufficiently low concentration was needed to avoid interference with the possibility of the developed multiplex assay to quantitatively and simultaneously detect the presence of GI and GII NV within one sample. Persistent contamination problems leading to false-positive results were encountered, but an investigation was performed towards the source of the contamination. The problem could be controlled and only occasional contamination has been observed. Objective 2: Two protocols for extraction of NV from soft red fruits (selected as fresh produce product) and ready-to-eat (RTE) foods were evaluated towards robustness and sensitivity. For the RTE foods, the protocol for RTE foods made use of a guanidine isothiocyanate containing reagent to extract viral RNA from the food sample (basic protocol called TriShort) with an eventual concentration/purification step (extended protocol called TriConc). The protocol for extraction of NV from soft red fruits consisted of alkaline elution of NV particles from the food, followed by polyethylene glycol precipitation and organic solvent purification. After purification, the RNA was detected by the multiplex real-time RT-PCR assay optimized in objective 1. The influence of (1) the NV inoculum level and (2) different food types on the recovery of NV from these foods was investigated for both protocols. Overall, the elution –precipitation protocol was able to recover NV from soft red fruits with efficiencies of 10 % to 20 % in most cases while the protocol for RTE foods yielded recovery efficiencies of >1% (TriShort protocol) and 0.1 to 10 % (TriConc protocol). For both NV extraction methods, taking into account all dilution factors resulted in a detection limit of approximately 104 genomic copies/10g. Simultaneous recovery of GI and GII NV in similar or 100-fold different concentrations was possible in both food categories. A significant influence of the NV inoculum level on its recovery was noticeable in both protocols as high inoculum levels were recovered more successfully and with a higher efficiency compared to low level inocula in both protocols. This phenomenon, together with the influence of the food type on the recovery was more explicit on the protocol for RTE foods compared to the protocol for soft red fruits. Objective 3: The multiplex real-time RT-PCR assay described in objective 1 and the virus extraction protocols described in objective 2 were combined to two NV detection methods. The murine norovirus 1 (MNV-1), a cultivable genogroups V NV, was in these detection methods used and evaluated as control reagent. MNV-1 was used to control the entire virus detection protocol (process control; PC), the reverse transcription reaction (reverse transcription control; RTC) and the real-time PCR reaction (internal amplification control; IAC) when detecting NV in foods. Evaluation showed that MNV-1 PC and RTC could be used for detection of inefficient extraction and inhibition of the RT-PCR, respectively. On the other hand, the MNV-1 IAC provided only little added value and it was suggested to leave this control out. Objective 4: Screening of 75 fruit samples for NV presence was performed using the protocol for soft red fruits (objective 2) and the multiplex real-time RT-PCR assay (objective 1). MNV-1 was used as PC, RTC and IAC. A total of 18 samples tested positive for GI and/or GII NV despite good bacteriological quality. Results obtained showed the difficulty of expressing positive (real-time) PCR results towards terms of public health threat if no associated diseases or outbreaks are reported. Although these low NV levels might indicate virus contamination at some point during the fresh produce chain, care should be taken to translate these results as a significant risk to the public health. Nevertheless, a possible risk for food borne transmission of NV from these food products cannot be excluded either. Genotyping results from 115 clinical samples originating from gastro-enteritis epidemics reported to the Scientific Institute of Public Health allowed us to characterise the NV strains implicated in these outbreaks between 2007 and 2010. Similarly, the creation of a stool bank with domestic animal clinical samples and NV screening in these samples in the first part of the NORISK project have allowed the characterisation of animal NVs especially in the bovine and porcine species. These results confirm that bovine and porcine NVs may be endemic in our counties but besides these animal NVs, no other animal NV was detected in the other animal species selected for the stool bank. Objective 5: After the introduction of Norovirus specific analysis method in the surveillance of foodborne outbreaks, it became clear, that Norovirus is an important agent causing foodborne outbreaks in Belgium. During the last three years it was even the leading reported agent. It became also clear that it is not so easy to define the transmission routes of Norovirus. By the introduction of a scenario for gastro-enteritis a classification based on the possible transmission route was possible. In all the reported outbreaks no primary contaminated food like bivalve shellfish or red fruits was involved. Secondary contaminated food plays an imported role in the transmission of Norovirus with an infected food handler as a crucial vector. Besides the food related outbreaks it became clear that person-to person transmission and a high environmental contamination are risk factors in the further transmission of Norovirus in the population The fact that many people are living close together in for example youth camps or elderly homes, the common use of sanitary facilities and the common preparation of meals, combined with the high infectivity of Norovirus and the existence of asymptomatic carriers, results in highly vulnerable populations in these conditions. Although Norovirus infections often end up in a positive way, they may have a high impact on the health (eg elderly homes) and may cause a lot of costs (less personnel at work) and sorrow (eg closure of a youth camp). Although both the prevention and decrease of the risk of a Norovirus infection are not evident, some measures have to be taken. A good hand-, toilet- and kitchen hygiene, a good infrastructure and the rapid signaling of gastro-enteritis outbreaks can decrease the risk of Norovirus infection and might restrict further spread of the virus. The knowledge rising from the Norovirus outbreaks reported at the NRL FBO allowed use to formulate and publish specific measures and recommendations for Norovirus outbreaks, which help the inspectors and physicians in the rapid diagnosis and prevention of the further transmission of Norovirus outbreaks. Objective 6: Throughout the NORISK project, NVs were detected in different food matrices available for human consumption, in humans and in animals like cattle and pigs. For a better comprehension of NV transmission routes, sequences of the detected NVs were determined and submitted for further analysis. Genotyping of NVs in food matrices came out to be a real challenge and consisted into a bottleneck as the amount of genetic material on food was insufficient for PCR amplification and sequencing. This obstacle was not overcome during our project and NV sequences were only obtained from clinical samples in humans and animals. Interesting was that no animal NVs were detected in samples originating from humans and no human sequences were amplified from animal clinical samples. Thus, there is no evidence of a potential interspecies NV transmission and zoonotic transmissions seem unlikely to occur. However NV, being an RNA virus, exhibit great genomic plasticity and changes in its genome could lead to the emergence of new NV variant with different biological proprieties that should not be left out (objective 7). Objective 7: Sequences obtained in the human and bovine clinical samples show different NV strains that exhibit incoherent clustering for the partial sequences of the polymerase and the capsid region indicating that they might be recombinant. For the human NV strains, although the majority of the gastroenteritis outbreaks were involved with GII.4 NVs in 2007 and 2008, other GII NVs were detected from the end of 2008 to 2010 along GII.4 NVs. Among these NVs, a variety of new recombinants were detected in different samples from different outbreaks between 2008 and 2010. New « super » polymerase sequences (GII.e and GII.g) related to the previously described GII.b polymerase were detected in the same period. The exact significance of the emergence of these polymerases or their origin has yet to be elucidated but their involvement with different outbreaks might indicate that they have a selective advantage upon the capsid parental strains. Based on sequencing data, norovirus (NV) recombinants have been described, but no experimental evidence of recombination in NVs has been documented. Using the murine norovirus (MNV) model, we investigated the occurrence of genetic recombination between two co-infecting wild-type MNV isolates in RAW cells. The design of a PCR-based genotyping tool allowed accurate discrimination between the parental genomes and the detection of a viable recombinant MNV (Rec MNV) in the progeny viruses. Genetic analysis of Rec MNV identified a homologous-recombination event located at the ORF1–ORF2 overlap. Rec MNV exhibited distinct growth curves and produced smaller plaques than the wild-type MNV in RAW cells. Here, we demonstrate experimentally that MNV undergoes homologous recombination at the previously described recombination hot spot for NVs, suggesting that the MNV model might be suitable for in vitro studies of NV recombination. Moreover, the results show that exchange of genetic material between NVs can generate viruses with distinct biological properties from the parental viruses. [less ▲]

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See detailNote synthétique sur l'évaluation et le calcul de la vulnérabilité des ménages au Niger : février 2011
Andres, Ludovic ULg; Lebailly, Philippe ULg

Report (2011)

L’analyse de la vulnérabilité alimentaire suscite une attention toute particulière des bailleurs de fond. En effet, depuis 1990, l’analyse et l’évaluation de celle-ci permet aux différentes institutions ... [more ▼]

L’analyse de la vulnérabilité alimentaire suscite une attention toute particulière des bailleurs de fond. En effet, depuis 1990, l’analyse et l’évaluation de celle-ci permet aux différentes institutions nationales et internationales présentes au Niger d’élaborer leurs stratégies, de cibler les populations ou zones bénéficiaires de leurs interventions ainsi que de prévenir et gérer les crises alimentaires. Cependant, les nombreuses crises alimentaires chroniques du Niger (1996-1997, 2001, 2004-2005, 2009-2010) suscitent néanmoins un certain questionnement quant à l’efficacité et l’efficience de cette évaluation. Cette note décrira certaines méthodologies d’évaluation de la vulnérabilité alimentaire les plus usitées au Niger. Au total, trois méthodologies ont été caractérisées, celle de la Cellule de Coordination du Système d’Alerte Précoce (CC/SAP), de certains Partenaires Techniques et Financiers (Save The Children, Action Contre la Faim, …) et du CC/SAP et de l’Institut National de la Statistique du Niger (INS-Niger). Cette description permettra de mieux cerner les spécificités de chacune d’elles et d’élaborer certaines remarques et recommandations. Ce document introduira, tout d’abord, le concept de vulnérabilité repris dans la littérature. Ensuite, il décrira les différentes méthodologies de calcul et d’évaluation de la vulnérabilité utilisées au Niger. Enfin, ces méthodologies seront analysées et critiquées en vue de présenter des propositions d’améliorations. Il en ressort que le niveau d’analyse de la vulnérabilité doit être affiné d’un point de vue départemental et communal. Il est essentiel de réaliser une distinction entre les ménages urbains et ruraux étant donné la diversité des stratégies opérées par ces ménages. L’évaluation de la vulnérabilité des ménages pastoraux et/ou transhumants devrait être repensée pour améliorer la prise en compte de ceux-ci. La recommandation principale de cette note est d’augmenter le nombre de ménages de l’échantillon d’analyse dans le but de mieux caractériser la vulnérabilité des ménages urbains, ruraux, pastoraux et de produire des indices de vulnérabilité par commune. [less ▲]

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