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See detailGeomorphic and Hydrological challenges in Africa: implications for soil and water conservation
Vanmaercke, Matthias ULg; Poesen, Jean

Conference (2017, April 24)

Expected scenarios of climate change and population growth confront Africa with various important challenges related to food, water and energy security. Many of these challenges are closely linked to the ... [more ▼]

Expected scenarios of climate change and population growth confront Africa with various important challenges related to food, water and energy security. Many of these challenges are closely linked to the impacts of soil erosion and other geomorphic processes, such as reduced crop yields, sedimentation of reservoirs and reduced freshwater quality. Despite the urgency and extent of many of these challenges, the causes and dynamics of these processes and their impacts remain severely understudied. This becomes apparent when the availability of e.g. soil erosion and catchment sediment export measurements for Africa is compared to that of other continents. Nonetheless, a substantial amount of geomorphic research has been conducted in Africa. Many of this work dates back from several decades ago, and were often only reported in ‘gray literature’ (e.g. internal reports). Here we present an overview of our current state of knowledge on soil erosion and its implications in Africa. We discuss which geomorphic process rate measurements are currently available and what can be learned from these with respect to the challenged raised above. We especially focus on our current understanding about the effectiveness of soil and water conservation techniques at various spatial and temporal scales. Based on specific case-studies (e.g. in Ethiopia and Uganda) and a meta-analysis of previous work, we highlight some research gaps, research needs and research opportunities when aiming to use Africa’s soil and water resources sustainably and efficiently [less ▲]

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See detailDetermining RUSLE P-factors for stonebunds and trenches in rangeland and cropland, Northern Ethiopia
Taye, Gebeyehu; Poesen, Jean; Vanmaercke, Matthias ULg et al

Conference (2017, April 24)

The implementation of soil and water conservation (SWC) measures in the Ethiopian highlands is a top priority to reduce soil erosion rates and to enhance the sustainability of agroecosystem. Nonetheless ... [more ▼]

The implementation of soil and water conservation (SWC) measures in the Ethiopian highlands is a top priority to reduce soil erosion rates and to enhance the sustainability of agroecosystem. Nonetheless, the effectiveness of many of these measures for different hillslope and land use conditions remains currently poorly understood. As a result, the overall effects of these measures at regional or catchment scale remain hard to quantify. This study addresses this knowledge gap by determining the cover-management (C) and support practice (P) factors of the Revised Universal Soil Loss Equation (RUSLE), for commonly used SWC measures in semi-arid environments (i.e. stone bunds, trenches and a combination of both). Calculations were based on soil loss data collected with runoff plots in Tigray, northern Ethiopia (i.e. 21 runoff plots of 600 to 1000 m2 , monitored during 2010, 2011 and 2012). The runoff plots were installed in rangeland and cropland sites corresponding to a gentle (5%), medium (12%) and steep (16%) slope gradients. The C and P factors of the RUSLE were calculated following the recommended standard procedures. Results show that the C-factor for rangeland ranges from 0.31 to 0.98 and from 0.06 to 0.39 for cropland. For rangeland, this large variability is due to variations in vegetation cover caused by grazing. In cropland, C-factors vary with tillage practices and crop types. The calculated P-factors ranged from 0.32 to 0.74 for stone bunds, from 0.07 to 0.65 for trenches and from 0.03 to 0.22 for a combination of both stone bunds and trenches. This variability is partly due to variations in the density of the implemented measures in relation to land use (cropland vs rangeland) and slope angles. However, also annual variations in P factor values are highly significant. Especially trenches showed a very significant decline of effectiveness over time, which is attributable to their reduced static storage capacity as a result of sediment deposition (e.g. for trenches in rangeland: 0.07-0.13 in 2010 to 0.37-0.65 in 2012). Hence, the results of this work may not only help in better modelling and quantifying the average long-term impacts of SWC measures over larger areas, but also show the importance of considering temporal variations of the effectiveness of SWC measures. [less ▲]

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See detailCancer associated fibroblast-derived integrin α11 regulates PDGFRβ signaling to promote breast cancer progression
Primac, Irina ULg; Blacher, Silvia ULg; cimino, Jonathan et al

Conference (2017, April 24)

CAF-specific proteins can provide important prognostic markers and targets for anticancer drugs. Recently, integrin α11 (ITGA11) emerged as a new biomarker of CAFs. ITGA11 is mainly expressed by ... [more ▼]

CAF-specific proteins can provide important prognostic markers and targets for anticancer drugs. Recently, integrin α11 (ITGA11) emerged as a new biomarker of CAFs. ITGA11 is mainly expressed by mesenchymal cells and is correlated with fibroblast activation and matrix reorganization. While the role of ITGA11 in wound healing has been well described, only a very limited number of reports have assessed its role in the cancer disease. This research project aims to investigate the role of stromal ITGA11 in breast cancer. To analyze the in vivo effects of ITGA11 on tumor insurgence, growth and metastasis, we crossed the oncogenic MMTv-PyMT mice with the ITGA11 KO/WT mice, which develop spontaneously breast tumors. ITGA11 deletion strongly delayed tumor growth and metastasis in PyMT mouse model. ITGA11 was poorly expressed at early stages of the tumor progression and its expression was strongly increased in the late stage invasive carcinomas. Importantly, a reduced angiogenesis and collagen content was observed in tumors lacking of ITGA11. Furthermore, a strong co-localization between ITGA11 and PDGFRb, but not other CAF markers such as alpha smooth actin, was also observed within the tumor stroma, suggesting that ITGA11 defines a subpopulation of CAFs, which is not represented by myofibroblasts, but rather PDGFRb+ CAFs. For mechanistic investigation, CAFs and breast cancer cells were isolated from the PyMT model. ITGA11 co-immunoprecipitated with PDGFRb in the isolated CAFs and regulated its phosphorylation. Interestingly, ITGA11-deficient CAFs failed to promote CAF and cancer cell invasion, in contrast to WT CAFs in a spheroid invasion assay. A high throughput comparative proteomics analysis on CAF spheroids in 3D a system was next performed. Proteomics data identified several proteins with relevance in the cancer disease which were significantly modulated in CAFs through ITGA11 down-regulation. The top-ranking candidates are under validation and molecular pathways, which may link these targets and ITGA11 will be further analyzed in the in vitro models. Overall, these in vivo and in vitro data show that ITGA11 defines a PDGFRβ+ subpopulation of CAFs distinct from α-SMA+ myofibroblasts that promote tumor cell invasion and angiogenesis at late stages of carcinoma evolution. ITGA11 is a promising target within the stroma of breast cancer and further investigations of its molecular signaling pathways will be of great relevance. [less ▲]

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See detailTransfert sol-plante et Procédés de phytoremédiation (Memoris)
Liénard, Amandine ULg

Conference given outside the academic context (2017)

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See detailCharacterizing root system characteristics with Electrical resistivity Tomography: a virtual rhizotron simulation
Rao, Sathyanarayan; Ehosioke, Solomon ULg; Lesparre, Nolwenn et al

Conference (2017, April 24)

Electrical Resistivity Tomography (ERT) is more and more used for monitoring soil water content in a cropped soil. Yet, the impact of roots on the signal is often neglected and a topic of controversy. In ... [more ▼]

Electrical Resistivity Tomography (ERT) is more and more used for monitoring soil water content in a cropped soil. Yet, the impact of roots on the signal is often neglected and a topic of controversy. In several studies related to soil-root system, it has been showed that the measured root mass density statistically correlates with the electrical conductivity (EC) data obtained from ERT. In addition, some studies suggest that some roots are more electrically conductive than soil for most water content. Thus, higher EC of roots suggest that it might have a measurable impact on ERT signals. In this work, virtual rhizotrons are simulated using the software package called R-SWMS that solves water and solute transport in plant root-soil system, including root growth. The distribution of water content obtained from R-SWMS simulation is converted into EC data using pedo-physical models. The electrical properties of roots and rhizosphere are explicitly included in the EC data to form a conductivity map (CM) with a very detailed spatial resolution. Forward ERT simulations is then carried out for CM generated for various root architectures and soil conditions to study the impact of roots on ERT forward (current and voltage patterns) and inverse solutions. It is demonstrated that under typical injection schemes with lateral electrodes, root system is hardly measurable. However, it is showed that adding electrodes and constraints on the ERT inversion based on root architecture help quantifying root system mass and extent. [less ▲]

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See detailThe growth and meat quality of H'mong chicken raised by industrial farming
Nguyen Van Duy, ULg; Vu Dinh, Ton; Nguyen Thi, Phuong

in Journal of Sciences of Agriculture Vietnams (2017), 15(4), 438-445

This study was carried out at the experimental farm of Vietnam National University of Agriculture from January to December, 2016 on H’mong chickens that were raised by industrial farming. H’mong chickens ... [more ▼]

This study was carried out at the experimental farm of Vietnam National University of Agriculture from January to December, 2016 on H’mong chickens that were raised by industrial farming. H’mong chickens were raised in three lots in order to observe the survival rate, growth capacity, FCR and quality of meat. The results show that Hmong chicken adapted well with industrial farming method, which supposedly contributed to the improvement in survival rate of chickens (94,1%) compared to traditional free-range farming method.. H'mong chickens have low weight and considerable growth speed. Average daily gain of H’mong chickens was increasing gradually from one to ten weeks of age and then decreasing. From one to 12 weeks, H'mong chickens consumes averagely 24.81 grams of feed per day and Feed Conversation Rate was 3.1 kg of feed/kg live body weight. Twelve week-old roosters and hens achieved body weight at 1206,7g and 1026,7g in respectively. H'mong chicken is a dual-purpose breed, producing an amount of thigh meat 1.3 times greater than breast meat. The proportion of iron in Hmong chicken meat is higher than that in other domestic chicken breeds and there are eight unsubstituted amino acids in the meat. Key works: H’mong chickens, industrial farming. [less ▲]

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See detailCattle grazing dynamics under contrasted pasture characteristics at temporal and spatial scales
Andriamandroso, Andriamasinoro ULg

Doctoral thesis (2017)

Grassland constitutes an important and a low-cost food source for grazing livestock. Optimal management should consider both forage resource productivity and animal needs. For cattle, grazing is a normal ... [more ▼]

Grassland constitutes an important and a low-cost food source for grazing livestock. Optimal management should consider both forage resource productivity and animal needs. For cattle, grazing is a normal behavior displayed in an attempt to eat the amount of forage to fulfill their nutritive requirements for maintenance and production. It is the most time-consumed activity of cows reared in pasture-based systems. With the increase of herd size, on one hand, farmers have been constrained to integrate innovative tools and techniques, such as milking robot, to improve the production system in particular to reduce the labor cost. On the other hand, such change might reduce time allocated for grazing on pasture. However pasture-based systems constitute a real pillar for sustainability as they are socially acceptable and environmentally profitable as they play an important role on ecosystem services and biodiversity provision. Studying grazing processes at individual level, which finally is the key point of animal-plant interactions, is a valuable research domain to enhance the knowledge about this mechanism and to feed decision support tools. This thesis aimed to link the changes in pasture characteristics to the grazing behavior of cattle in order to better understand the grazing strategy under different pasture characteristics and forage allowances. To allow an individual monitoring, sensor technology has integrated within farms and livestock researches to monitor many physical variables, inducing the emergence of precision livestock farming approach. Different types of sensors were designed, and already commercialized for some, primarily for physiological status detections such as heat, parturition or diseases. Grazing behaviors could be monitored using pressure, electromyography, acoustic or accelerometric sensors by classifying posture and movements of the animal into unitary behaviors (grazing, ruminating, resting, walking, etc.) and finer behavior such as chews and bites through jaw movements’ detection. When compared to real observation, detection accuracies of these behaviors were variable according to the type of sensor, its position on the animal during data acquisition on pasture, the data recording frequency, the time-window and the method dedicated to the post-recording data analysis. State-of-the-art analysis demonstrated a great performance of accelerometers for unitary behaviors and bites detection. An inertial measurement unit, integrating accelerometer, gyroscope and location sensors, was used for recording cattle movements during grazing at high sampling rate (100Hz). It allows a correct detection of grass intake and rumination behaviors with an average accuracy of 91% using 1-second time-window when calibrating and validating the detection algorithm. Deeper analysis of accelerometric signal allowed us to detect bites and chews performed during grazing and ruminating. Effects of pasture heights on grazing bites characteristics were differentiated by a higher frequency when pasture is at a lower height. Finally when combined to geographical information, a similar pattern was observed for cattle grazing on the same spot confirming their herd movement during grazing in terms of bites location. Differences were visible under different pasture heights but not significant. Such bites location, combined with continuous monitoring of cattle behaviors, through use of sensors, should be furtherly linked with more pasture characteristics, if possible with the same accuracy, and monitored on longer period in order to obtain a complete coverage of cattle grazing strategy and the effect of contrasted environment in order to purpose valuable tool for a better grazing management. [less ▲]

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See detailTo be plastic is fantastic: delineate coral species niches for assessing their tolerance to changes
Denis, Vianney; Sturaro, Nicolas ULg; Yang, Shan-Hua et al

Conference (2017, April 24)

Climatic and anthropogenic disturbances alter coral reefs by reconfiguring existing coral assemblages. Surviving species are selected by the new environment based on particular traits that they may ... [more ▼]

Climatic and anthropogenic disturbances alter coral reefs by reconfiguring existing coral assemblages. Surviving species are selected by the new environment based on particular traits that they may exhibit. The plasticity in traits will define ecological strategies associated with contrasted degrees of tolerance to changes. In this process, specialists are expected to tolerate few changes to the environmental conditions and are restricted to specific habitat. To contrast, generalists can cope with a wider range of environmental conditions by readjusting traits according to the habitat’s features. Ecological strategies in corals have been exclusively defined according to species’ trait averages, irrespective of individual variations. Challenges representing the acquisition and use of energy have also tended to be oversimplified, specifically by the choice of easy traits in the absence of strong scientific evidence. Here, we propose a framework to re-examine strategies in scleractinian corals by focusing on the intraspecific variation of traits. We will show how the characteristics of a given species niche can help coral species to tolerate changes, illustrating this approach with examples taken from high-latitude locations and mesophotic coral ecosystems. We will demonstrate that multidisciplinary approach focusing on three major characteristics of the coral holobiont (its physiology, trophic ecology, and associated micriobiome), we can enhance the comprehension of ecological plasticity of coral species and predict future ecosystem reconfiguration. [less ▲]

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See detailComment on “Hypogonadotrophic hypogonadism due to a mutation in the luteinizing hormone β-subunit gene”
VALDES SOCIN, Hernan Gonzalo ULg; Daly, Adrian ULg; BECKERS, Albert ULg

in Korean Journal of Internal Medicine (The) (2017), 32(3), 566-567

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See detailClay minerals behaviour in thin sandy clay-rich lacustrine turbidites (Lake Hazar, Turkey)
El Ouahabi, Meriam ULg; Hubert, Aurelia ULg; Lamair, Laura ULg et al

Poster (2017, April 23)

Turbidites have been extensively studied in many different areas using cores or outcrop, which represent only an integrated snapshot of a dynamic evolving flow. Laboratory experiments provide the missing ... [more ▼]

Turbidites have been extensively studied in many different areas using cores or outcrop, which represent only an integrated snapshot of a dynamic evolving flow. Laboratory experiments provide the missing relationships between the flow characteristics and their deposits. In particular, flume experiments emphasize that the presence of clay plays a key role in turbidity current dynamics. Clay fraction, in small amount, provides cohesive strength to sediment mixtures and can damp turbulence. However, the degree of flocculation is dependent on factors such as the amount and size of clay particles, the surface of clay particles, chemistry and pH conditions in which the clay particles are dispersed. The present study focuses on thin clayey sand turbidites found in Lake Hazar (Turkey) occurring in stacked thin beds. Depositional processes and sources have been previously studied and three types were deciphered, including laminar flows dominated by cohesion, transitional, and turbulence flow regimes (Hage et al., in revision). For the purpose of determine the clay behavior in the three flow regimes, clay mineralogical, geochemical measurements on the cores allow characterising the turbidites. SEM observations provide further information regarding the morphology of clay minerals and other clasts. The study is particularly relevant given the highly alkaline and saline water of the Hazar Lake. Clay minerals in Hazar Lake sediments include kaolinite (1:1-type), illite and chlorite (2:1-type). Hazar lake water is alkaline having pH around 9.3, in such alkaline environment, a cation-exchange reaction takes place. Furthermore, in saline water (16‰), salts can act as a shield and decrease the repulsive forces between clay particle surfaces. So, pH and salt content jointly impact the behaviour of clays differently. Since the Al-faces of clay structures have a negative charge in basic solutions. At high pH, all kaolinite surfaces become negative-charged, and then kaolinite particles are dispersed, and the suspension is stabilized supported by our SEM observations. In alkaline water, kaolinite reveals a lower degree of consolidation. While, alkaline water has no measurable effect on illite and chlorite surface properties due to the absence of modifications in charge. Illite and chlorite form with other clasts clusters or aggregate structures in suspension when the particle interactions are dominated by attractive energies were formed. The aggregate structure plays a major part in the flow behavior of clay suspensions. Flocs will immobilize the suspending medium, and give rise to increasing viscosity and yield strength of the suspension. [less ▲]

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See detailEpithelial lining fluid penetration of temocillin administered by continuous infusion in critically ill patients with nosocomial pneumonia
VISEE, Clotilde ULg; LAYIOS, Nathalie ULg; MISTRETTA, Virginie ULg et al

Conference (2017, April 23)

The administration of 6g per day of temocillin by continuous infusion in critically patients with severe nosocomial pneumonia allows a penetration ratio, measured by the ELF/plasma ratio of AUCs, of 0.14 ... [more ▼]

The administration of 6g per day of temocillin by continuous infusion in critically patients with severe nosocomial pneumonia allows a penetration ratio, measured by the ELF/plasma ratio of AUCs, of 0.14 and 0.57 and a mean (± SE) ELF concentration , in mg/L, of 9.8 ± 1.3 and 9.8 ± 1.6 for total and free drug, respectively. Standard error of AUCs should be calculated by the Bootstrap method and Monte Carlo simulations should be performed for subsequent PK/PD analysis. [less ▲]

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See detailApport de l'ENMG aux syndromes douloureux diffus
WANG, François-Charles ULg

Scientific conference (2017, April 22)

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See detailAre Vitek2 system and E-test relevant and reliable for determining susceptibility to temocillin?
VISEE, Clotilde ULg; FRIPPIAT, Frédéric ULg; DESCY, Julie ULg et al

Poster (2017, April 22)

Compared to BMD, Vitek2® seems to overestimate sensitivity and underestimate resistance, while E-test® seems to overestimate resistance, pleading for the use of BMD when evaluating susceptibility to ... [more ▼]

Compared to BMD, Vitek2® seems to overestimate sensitivity and underestimate resistance, while E-test® seems to overestimate resistance, pleading for the use of BMD when evaluating susceptibility to temocillin. However, this study, which is currently enrolling more patients, will include more isolates in order to meet FDA criteria set out in Cumitech 31A for validation of method comparison [less ▲]

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See detailEtude des traitements numériques de base dans le syndrome 22q11: Impact des troubles visuo-spatiaux
Attout, Lucie ULg; Noël, Marie-Pascale; Vossius, Line ULg et al

Conference (2017, April 22)

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See detail3D investigation into the bust of Akhenaten in the Louvre Museum
Laboury, Dimitri ULg; Mulliez, Maud

Conference (2017, April 22)

Purchased in 1905 by G. Bénédite from the Antiquity market, the unprovenanced limestone bust of Akhenaten now kept in the Louvre Museum (under the inventory number E 11076) is world-famous but, in the end ... [more ▼]

Purchased in 1905 by G. Bénédite from the Antiquity market, the unprovenanced limestone bust of Akhenaten now kept in the Louvre Museum (under the inventory number E 11076) is world-famous but, in the end, rather poorly studied. In the context of an international research project entitled RetroColor 3D (funded by the Région Nouvelle Aquitaine, France, and the University of Bordeaux Montaigne, at Archeovision - UMS 3657 of the CNRS), this exceptional piece of sculpture was investigated anew with the help of 3D reconstruction as a methodological tool. Reporting on this transdisciplinary analysis, the paper will explain how this led to a better understanding of the bust’s original function in the creation of royal portraiture during the so-called Amarna period. [less ▲]

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See detailAnalyse spatiale intrasite basée sur un Système d'Information Géographique et appliquée aux vastes sites de plein air du Paléolithique moyen en France septentrionale. L’Exemple de Caours (Somme, France).
Moreau, Gwénaëlle ULg; Locht, Jean-Luc

Conference (2017, April 21)

Durant le Paléolithique moyen, l’alternance entre les périodes glaciaire et interglaciaire a rendu le peuplement de la France septentrionale discontinu. Cette région bénéficie d’un bon cadre ... [more ▼]

Durant le Paléolithique moyen, l’alternance entre les périodes glaciaire et interglaciaire a rendu le peuplement de la France septentrionale discontinu. Cette région bénéficie d’un bon cadre chronostratigraphique permettant l’étude des peuplements néandertaliens. Cependant certains aspects de leurs comportements restent encore mal caractérisés, particulièrement la fonction des sites reste souvent à préciser. L’étude de l’organisation spatiale intrasite apporte des éléments de réponse à ces questions. La fouille d’un site du Paléolithique moyen ne met pas directement en évidence l’organisation spatiale des lieux de vie, une modélisation est nécessaire pour la déceler. Nous avons donc débuté la construction d’un protocole d’analyse spatiale basé sur un Système d’Information Géographique et appuyé sur les sites de Caours. Ce site possède un rôle majeur de par sa superficie et l’excellente préservation des restes fauniques. Nous montrons ici l’existence d’une organisation spatiale sous forme de zones de concentration de vestiges en corrélant plusieurs méthodes – parmi lesquelles le K-mean Clustering et la Kernel Density Estimation. Nous préciserons ensuite la fonction de ces zones au sein d’un espace de vie et leur interaction entre elles au travers de la distribution spatiale des différents vestiges fauniques ou lithiques. [less ▲]

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See detailThe tax on legal entities in the light of civil law: a positive and prospective study of the income taxation for certain actors within the social economy
Garroy, Sabine ULg

Scientific conference (2017, April 21)

Dans le cadre de cette chaire Francqui, plusieurs doctorants belges ont eu l’occasion d’exposer leurs travaux et d’échanger avec le Pr. Dr. Dr.h.c. Wolfgang Schön, au cours de six classes d’excellence ... [more ▼]

Dans le cadre de cette chaire Francqui, plusieurs doctorants belges ont eu l’occasion d’exposer leurs travaux et d’échanger avec le Pr. Dr. Dr.h.c. Wolfgang Schön, au cours de six classes d’excellence dispensées à Liège et Anvers. [less ▲]

Detailed reference viewed: 12 (4 ULg)