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See detailMapping of kisspeptin fibres in the brain of the pro-oestrous rat.
Desroziers, Elodie ULg; Mikkelsen, J.; Simonneaux, V. et al

in Journal of Neuroendocrinology (2010), 22(10), 1101-12

Kisspeptins are a family of small peptides that play a key role in the neuroendocrine regulation of the reproductive function through neural pathways that have not yet been completely identified. The ... [more ▼]

Kisspeptins are a family of small peptides that play a key role in the neuroendocrine regulation of the reproductive function through neural pathways that have not yet been completely identified. The present study aimed to investigate the distribution of kisspeptin neurone fibres in the female rat brain by comparing precisely the immunoreactive pattern obtained with two antibodies: one specifically directed against kisspeptin-52 (Kp-52), the longest isoform, and the other directed against kisspeptin-10 (Kp-10), whose sequence is common to all putative mature isoforms. With both antibodies, immunoreactive cell bodies were exclusively observed in the arcuate nucleus, and immunoreactive fibres were confined to the septo-preoptico-hypothalamic continuum of the brain. Fibres were observed in the preoptic area, the diagonal band of Broca, the septohypothalamic area, the anteroventral periventricular, suprachiasmatic, supraoptic, paraventricular and periventricular nuclei, the dorsal border of the ventromedian nucleus, the dorsomedial and arcuate nuclei, and the median eminence. In the latter structure, varicose fibres were mainly distributed in the internal layer and were detected to a lesser extent throughout the external layer, including around the deeper part of the infundibular recess. Most regions of immunoreactive cells and fibres matched perfectly for the two antibodies. However, fibres in the dorsolateral septum, anterior fornix, accumbens nucleus and the lateral bed nucleus of the stria terminalis were only recognised by antibody anti-Kp-10, suggesting that anti-Kp-10 may recognise a wider range of kisspeptin isoforms than anti-Kp-52 or cross-react with molecules other than kisspeptin in rat tissue. Overall, these results illustrate the variety of projection sites of kisspeptin neurones in the rat and suggest that these peptides play a role in different functions. [less ▲]

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See detailMapping of kisspeptin projections in the midbrain of the pro-oestrus rat
Desroziers, Elodie ULg; Mikkelsen, Jens; Simmoneaux, Valérie et al

Poster (2010, July)

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See detailMapping of riparian invasive species with supervised classification of Unmanned Aerial System (UAS) imagery
Michez, Adrien ULg; Piégay, Hervé; Lisein, Jonathan ULg et al

in International Journal of Applied Earth Observation and Geoinformation (2016), 44

Riparian zones are key landscape features, representing the interface between terrestrial and aquatic ecosystems. Although they have been influenced by human activities for centuries, their degradation ... [more ▼]

Riparian zones are key landscape features, representing the interface between terrestrial and aquatic ecosystems. Although they have been influenced by human activities for centuries, their degradation has increased during the 20th century. Concomitant with (or as consequences of) these disturbances, the invasion of exotic species has increased throughout the world’s riparian zones. In our study, we propose a easily reproducible methodological framework to map three riparian invasive taxa using Unmanned Aerial Systems (UAS) imagery: Impatiens glandulifera Royle, Heracleum mantegazzianum Sommier and Levier, and Japanese knotweed (Fallopia sachalinensis (F. Schmidt Petrop.), Fallopia japonica (Houtt.) and hybrids). Based on visible and near-infrared UAS orthophoto, we derived simple spectral and texture image metrics computed at various scales of image segmentation (10,30, 45, 60 using eCognition software). Supervised classification based on the random forests algorithm was used to identify the most relevant variable (or combination of variables) derived from UAS imagery for mapping riparian invasive plant species. The models were built using 20% of the dataset, the rest of the dataset being used as a test set (80%). Except for H. mantegazzianum, the best results in terms of global accuracy were achieved with the finest scale of analysis (segmentation scale parameter = 10). The best values of overall accuracies reached 72%, 68%, and 97% for I. glandulifera, Japanese knotweed, and H. mantegazzianum respectively. In terms of selected metrics, simple spectral metrics (layer mean / camera brightness) were the most used. Our results also confirm the added value of texture metrics (GLCM derivatives) for mapping riparian invasive species. The results obtained for I. glandulifera and Japanese knotweed do not reach sufficient accuracies for operational applications. However, the results achieved for H. mantegazzianum are encouraging. The high accuracies values combined to relatively light model-inputs needed (delineation of a few umbels) make our approach a serious contender as a cost-effective tool to improve the field management of H. mantegazzianum. [less ▲]

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See detailMapping of soil-sediment systems contaminations around a metal-ore smelter : The example of Cu in Lubumbashi (R.D.Congo).
Mpundu, Michel; Mukobo, Robert-Prince; Kaya Muyumba, Donato ULg et al

Poster (2009)

The Katanga is famous for its high richness in metal ores, mainly Cu- and Co-minerals. The ore treatments activities lead to metal spreading in the environment which do endanger the viability of ... [more ▼]

The Katanga is famous for its high richness in metal ores, mainly Cu- and Co-minerals. The ore treatments activities lead to metal spreading in the environment which do endanger the viability of ecosystems and human health. The contaminations of soils and sediments around the Gecamines smelter in Lubumbashi have been evaluated through a multi-scale approach. In the first stage, a reference system about the natural contents in soils has been implemented. The main units of the detailed (1:20 000) soil map have been characterized through field observations and laboratory determinations : acido-basic and organic status, particle size distribution, cationic exchange capacity, total contents in Al, Fe, Mn, Cu, Co, Cd, Pb, Zn. An exploratory mapping of soil contaminations (Cu, Co, Cd, Pb, Zn) centered on the Gecamines cheminey was then conducted as a second stage of the approach. Detailed investigations were finally performed in the Gecamines district where signs of soil degradation were the highest. The spatial continuity and the differenciation (C : C0+C ratio) of the studied parameters appeared weak. No clear effect of the dominant wind direction on the spatial distribution of the contaminants could be identified despite a clear degradation of the ecosystem in the area under dominant wind. However the detailed approach showed evidences of (i) significant wind deposits in the Gecamines district, (ii) and local man-made deposits but also (ii) important processes of redistribution in the landscape through erosion/sedimentation or anthropic activities. Our results point out the difficulty to identify the sources of contaminations in an urban environment and stress the need to have approaches with complementary levels of details. [less ▲]

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See detailMapping of soil-sediment systems contaminations around a metal-ore smelter. The example of Cu in Lubumbashi (R.D. Congo)
Mpundu, Michel; Kaya Muyumba, Donato ULg; N'gongo, Michel et al

Conference (2009, December 02)

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See detailMapping of the bovine growth hormone secretagogue receptor (GHS-R) and polymorphism study in cattle
Colinet, Frédéric ULg; Eggen, André; Gengler, Nicolas ULg et al

Poster (2006, December)

A third control pathway of the Growth Hormone (GH) secretion has come into picture since the development of synthetic compounds known as Growth Hormone Secretagogues (GHSs). The GHS Receptor (GHS-R) and ... [more ▼]

A third control pathway of the Growth Hormone (GH) secretion has come into picture since the development of synthetic compounds known as Growth Hormone Secretagogues (GHSs). The GHS Receptor (GHS-R) and its subtype are abundantly located in the hypothalamus-pituitary unit, but are also distributed in other central areas and peripheral tissues. The GHS-R belongs to the G-protein coupled receptor family with seven transmembrane domain architecture. In order to determine the GHS-R gene sequence, total mRNA was extracted from abomasum and two types of GHS-R cDNA were identified. These two types are transcript variants (1a and 1b) of the same GHS-R gene. The gene encompasses two exons and a single intron. Using a 3000 Rad hybrid panel, the GHS-R gene was mapped to Bos taurus autosome 1 (BTA 1). This localization on BTA 1 agrees totally with comparative data between cattle and human since BTA 1 corresponds to part of human chromosome 3 where human GHSR is also mapped. By two-point analysis, most significantly linked marker are BL26 and BMS4031 (both LOD score : 5,66). Some studies detected different QTLs near these markers like for growth rate, carcass yield, milk portein and milk yield. In the cattle industry, it is of economical importance to increase plasma GH secretion because it is associated with faster growth, less fat stores and improved milk production. Being of economical importance and the detected QTLs near the GHS-R gene, it would be interesting to study the polymorphism on the bovine GHS-R gene. Screening for polymorphisms in the two exons on ten Belgian Blue bulls, ten Holsteins bulls and ten Limousin bulls revealed a total of four single nucleotide polymorphisms (SNPs): three SNPs are in the first exon and one SNP in the second exon. In order to evaluate if GHS-R could be involved in genetic variation for growth rate, carcass yield, milk portein and milk yield, an association study between SNPs on GHS-R gene and these traits could be performed in a major cattle population. [less ▲]

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See detailMapping of vegetation water content using Shortwave Infrared SPOT5 data to monitor irrigation in semi-arid regions.
Benabdelouahab, Tarik ULg; Balaghi, Riad; Lionboui, Hayat et al

Conference (2014, May 28)

Half of world’s food comes from irrigated area that uses about 72% of available water resources. In Morocco, water availability is the main limiting factor for crop growth and final yield and it is ... [more ▼]

Half of world’s food comes from irrigated area that uses about 72% of available water resources. In Morocco, water availability is the main limiting factor for crop growth and final yield and it is becoming a national priority for the agricultural sector. This situation leads the stakeholders to define most favorable strategies in planning and management of available water resources, on one hand, and to assess accurately vegetation water content status, on the other hand, in order to improve irrigation scheduling and prevent water stress adversely affecting yield. Remotely sensed reflectance has been used to estimate vegetation water content for different crops and to monitor water irrigation per surface unit, considering its high temporal and spatial resolution. In this study, we used two spectral indices of vegetation water content indicator (the Normalized Difference Infrared Index (NDII) and the Moisture Stress Index (MSI)) developed using Near Infrared (NIR) and Short Wave Infra-Red (SWIR) bands. The study area is the irrigated perimeter of Tadla in Morocco (35% dominated by irrigated wheat crop). In a first step, we compared observed vegetation water content of 16 studied plots of wheat and derived spectral indices NDII and MSI at the end of cropping season. The two images used at this step were acquired on March 26, 2013 and on April 11, 2013 when soil was fully covered by vegetation. Statistical analyses showed that the two spectral indices, NDII and MSI, simulated accurately vegetation water content. The statistical indicators, r, R², RMSE, nRMSE and MAE were -0.81, 0.65, 3.26% of water content (≈0.13 kg/m²), 4.26% and 2.69% for the NDII and 0.81, 0.65, 3.27% of water content (≈0.14 kg/m²), 4.27% and 2.72% for the MSI, respectively. To validate these results, we compared observed vegetation water content values and those predicted using the k-fold CV method. The errors were minimal for NDII and MSI, and the indicators of model evaluation obtained for predicted vegetation water content from NDII were: RMSE = 3.17%, nRMSE = 4.13%, MAE = 2.52% and R²=0.64. For MSI, these indicator were RMSE = 3.28%, nRMSE = 4.29%, MAE = 2.68% and R²=0.61. In a second step, we delimited the cereal area in the studied perimeter using a supervised classification method. The classification has been validated and the overall accuracy and Kappa coefficient were estimated respectively at 96.7% and 0.9545. Based on the regression model resulting from the comparison between NDII and measured vegetation water content, we produced maps of vegetation water content of wheat over the whole Beni-Moussa East irrigated area (41,000 hectares). The results of this work demonstrated the potential of spectral indices (NDII and MSI) derived from SPOT5 satellite images data to quantify and map vegetation water content of wheat. It showed also the potential of the SWIR band to improve the monitoring of irrigation by mapping water stress of wheat at field and regional level. [less ▲]

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See detailMapping Out the ‘Time Zones’ of Diaspora in Bharati Mukherjee’s Desirable Daughters
Munos, Delphine ULg

in Makokha, J. K. S.; Wawrzinek, Jennifer; West-Pavlov, Russell (Eds.) Border-Crossings: Narrative and Demarcation in Postcolonial Literatures and Media (2012)

Although Bharati Mukherjee is famous, or rather infamous, for her shameless embrace of America and its melting-pot ideology, in Desirable Daughters India, the homeland, is unexpectedly made to re-enter ... [more ▼]

Although Bharati Mukherjee is famous, or rather infamous, for her shameless embrace of America and its melting-pot ideology, in Desirable Daughters India, the homeland, is unexpectedly made to re-enter the stage of immigrant identity construction. In many respects it would seem that it has now become untenable to represent immigrant identity in terms of a one-directional movement from “India” to “America.” In Desirable Daughters the rise of India, the accelerated time/space compression of late capitalism, the post-90s paradigm shift in matters of transnational migration, the emphasis on return migrations and the emergence of a new global interaction indeed dramatically outflank Mukherjee’s previous narrative of American “exceptionalism” – which suddenly seems dated by comparison. By portraying the complex transnational network of connections operating between RIs (Resident Indians) and NRIs (Non Resident Indians), Mukherjee’s book gestures towards the “de-spatialization” of immigrant identity construction and its consequent “re-metaphorization” in terms of “time zones.” What is more, the increasingly compelling influence of contemporary India on the Indo-American diasporic subjectivity marks a “back to the future” return of the repressed which temporally repositions migrant identity between a ghostly time of repetition and a “hauntology” of new becomings. What Mukherjee suggests, I will contend, is that immigrant agency and self-fashioning cannot be associated anymore with the “pioneering spirit” of forward-looking characters that discard their “Indianness” upon (geographical) entry into the West. In my reading of Desirable Daughters the protagonist’s zigzagging path to self-transformation will be emphasized, so that it will become apparent that time has become the fourth space through which new spaces for diasporic identity can be renegotiated. [less ▲]

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See detailMapping overland flow hazard in order to enhance citizens’ awareness of head catchment hydrology
Pineux, Nathalie ULg; Colard, François; Degré, Aurore ULg

Conference (2012, November 15)

Between 1998 and 2004, Europe suffered from more than hundred major inundations, responsible for some 700 deaths, for the moving of about half a million of people and the economic losses of at least 25 ... [more ▼]

Between 1998 and 2004, Europe suffered from more than hundred major inundations, responsible for some 700 deaths, for the moving of about half a million of people and the economic losses of at least 25 billions Euros covered by the insurance policies. Within this context, EU launched the 2007/60/CE directive. This directive aims at a better evaluation of the risks and a better coordination of prevention, protection and crisis management. In most countries, inundation maps only include rivers’ overflowing. In Wallonia (southern part of Belgium), it was decided to include overland flows and mudflows in the flood hazard map. Indeed, the cleaning operations for a village after a storm can lead to an estimated cost of 11 000 €. Average construction cost of retention dams to control off-site damage caused by floods and muddy flows was valued at 380 000€, and yearly dredging costs associated with these retention ponds at 15 000€. A specific study in Gembloux (25 000 inhabitants) estimated the mean annual cost for the runoff damages to 20 000€. This cost only consists of the physical damages caused to the settlements and movable properties of the residents as well as the emergency operations of the firemen and the city. On top of damages to public infrastructure (clogging of trenches, silting up of retention ponds) and to private property, runoff and mud flows generate a significant loss of arable land. Yet, the soil is not an unlimited resource. Moreover, sediments’ transfer to watercourses alters their physical and chemical quality. And that is not to mention the increased psychological stress for people. But head catchment hydrology is not well known. Mapping the overland flood and mud flow hazard over a 17000 km² region is a real challenge. This contribution will present the pragmatic methodology used in Wallonia. In accordance with the Directive, different maps are produced (25, 50 and 100 years of return period and an extreme scenario). Local characteristics are taken into account: rainfall statistics, soil data, land use and relief. They are used to assess runoff production and transfer to an outlet identified as the point where runoff enters the permanent river network. Peak discharge values are used as basis for the mapping. The maps locate the water paths using a colour chart based on the peak discharge. Summer 2011 and spring 2012 storm events as well as a survey made at the municipalities’ level allowed us to validate in some ways the maps produced. Whereas this first approach at regional scale includes uncertainties, the aim of these maps is currently to prompt recognition of the runoff inundation hazard. It is of major importance for soil conservation and citizens’ protection. Above all, it should contribute to lower the damages by early prevention during the design of town-planning projects. [less ▲]

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See detailMapping Posidonia oceanica meadows through time A story of precision, evaluation and fragmentation
Abadie, Arnaud ULg; Jousseaume, Matthieu; Lejeune, Pierre et al

Poster (2015, May)

Over the last decades, the interest in mapping Posidonia oceanica beds has increased along with the improvement of the equipment’s precision of data acquisition. In Calvi Bay (Corsica, France) the meadows ... [more ▼]

Over the last decades, the interest in mapping Posidonia oceanica beds has increased along with the improvement of the equipment’s precision of data acquisition. In Calvi Bay (Corsica, France) the meadows cover an area of about 5 km² and are found at a depth ranging from 3 m to 37 m. The availability of three distinct datasets for 1997, 2002 and 2010 allowed to assess changes in the patchiness of the meadows in the bay and to investigate evolution of maps precision through a surface analysis via GIS software. Thus, three maps were elaborated combining aerial photographs and side scan sonar images. The meadows percentage of cover through time was assessed using four bathymetric sections: 0-10 m, 11-20 m, 21-30 m and 31-40 m. Differences in the patchiness of P. oceanica meadows between 1997 and 2010 appear to be moderate (less than 3 %) in the sections 0-10 m and 11-20 m and then greatly increase with depth: 24 % at 21-30 m and 39 % at 31-40 m. This amazing regression seems hardly natural and unlikely given the slight quantity of human activities that can cause damages on the P. oceanica meadows of the Calvi Bay. These results are likely to be mainly due to the improvement of precision and resolution of the aerial photographs (5 m in 1997, 0.8 m in 2002 and 0.5 m in 2010) and sonar images (5 m in 1997, 3 m in 2002 and 0.5 m in 2010). An issue of habitat determination (human vs instrumental) linked with the method adopted for mapping can also cause differences in the percentage of cover. Given the different accuracy among the three maps, the real regression and fragmentation of P. oceanica meadows could be hardly assessed. However, in several areas where the human activities are important, a clear regression or even a disappearance of the meadows has been observed. It is obvious that the last maps are more accurate than the previous ones and, thus, the former can be used for management purpose as well as for study on the patchiness; however, they still keep uncertainty no matter which method is used to create them. [less ▲]

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See detailMapping QTL influencing gastrointestinal nematode burden in Dutch Holstein-Friesian dairy cattle.
Coppieters, Wouter ULg; Mes, Ted H M; Druet, Tom ULg et al

in BMC Genomics (2009), 10

BACKGROUND: Parasitic gastroenteritis caused by nematodes is only second to mastitis in terms of health costs to dairy farmers in developed countries. Sustainable control strategies complementing ... [more ▼]

BACKGROUND: Parasitic gastroenteritis caused by nematodes is only second to mastitis in terms of health costs to dairy farmers in developed countries. Sustainable control strategies complementing anthelmintics are desired, including selective breeding for enhanced resistance. RESULTS AND CONCLUSION: To quantify and characterize the genetic contribution to variation in resistance to gastro-intestinal parasites, we measured the heritability of faecal egg and larval counts in the Dutch Holstein-Friesian dairy cattle population. The heritability of faecal egg counts ranged from 7 to 21% and was generally higher than for larval counts. We performed a whole genome scan in 12 paternal half-daughter groups for a total of 768 cows, corresponding to the approximately 10% most and least infected daughters within each family (selective genotyping). Two genome-wide significant QTL were identified in an across-family analysis, respectively on chromosomes 9 and 19, coinciding with previous findings in orthologous chromosomal regions in sheep. We identified six more suggestive QTL by within-family analysis. An additional 73 informative SNPs were genotyped on chromosome 19 and the ensuing high density map used in a variance component approach to simultaneously exploit linkage and linkage disequilibrium in an initial inconclusive attempt to refine the QTL map position. [less ▲]

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See detailMapping QTL influencing muscularity in a Texel x Romanov intercross
Marcq, Fabienne ULg; Elsen, J.-M.; Marot, V. et al

(2000)

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See detailMapping quantitative trait loci causing the muscular hypertrophy of Belgian Texel sheep
Marcq, Fabienne ULg; Elsen, J.-M.; Marot, V. et al

(1999)

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See detailMapping quantitative trait loci controlling milk production by exploiting progeny testing
Georges, Michel ULg; Nielsen, D.; Mackinnon, M. et al

in Genetics (1995), 139

We have exploited "progeny testing" to map quantitative trait loci (QTL) underlying the genetic variation of milk production in a selected dairy cattle population. A total of 1,518 sires, with progeny ... [more ▼]

We have exploited "progeny testing" to map quantitative trait loci (QTL) underlying the genetic variation of milk production in a selected dairy cattle population. A total of 1,518 sires, with progeny tests based on the milking performances of > 150,000 daughters jointly, was genotyped for 159 autosomal microsatellites bracketing 1645 centimorgan or approximately two thirds of the bovine genome. Using a maximum likelihood multilocus linkage analysis accounting for variance heterogeneity of the phenotypes, we identified five chromosomes giving very strong evidence (LOD score > or = 3) for the presence of a QTL controlling milk production: chromosomes 1, 6, 9, 10 and 20. These findings demonstrate that loci with considerable effects on milk production are still segregating in highly selected populations and pave the way toward marker-assisted selection in dairy cattle breeding. [less ▲]

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See detailMapping shallow soil moisture profiles at the field scale using full-waveform inversion of ground penetrating radar data
Minet, Julien ULg; Wahyudi, A.; Bogaert, P. et al

in Geoderma (2011), 161

Full-waveform inversions were applied to retrieve surface, two-layered and continuous soil moisture profiles from ground penetrating radar (GPR) data acquired in an 11-ha agricultural field situated in ... [more ▼]

Full-waveform inversions were applied to retrieve surface, two-layered and continuous soil moisture profiles from ground penetrating radar (GPR) data acquired in an 11-ha agricultural field situated in the loess belt area in central Belgium. The radar system consisted of a vector network analyzer combined with an off-ground horn antenna operating in the frequency range 200–2000 MHz. The GPR system was computer controlled and synchronized with a differential GPS for real-time data acquisition. Several inversion strategies were also tested using numerical experiments, which in particular demonstrated the potentiality to reconstruct simplified two-layered configurations from more complex, continuous dielectric profiles as prevalent in the environment. The surface soil moisture map obtained assuming a one-layered model showed a global moisture pattern mainly explained by the topography while local moisture patterns indicated a line effect. Two-layered and profile inversions provided consistent estimates with respect to each other and field observations, showing significant moisture increases with depth. However, some discrepancies were ob- served between the measured and modeled GPR data in the higher frequency ranges, mainly due to surface roughness effects which were not accounted for. The proposed GPR method and inversion strategies showed great promise for high-resolution, real-time mapping of soil moisture at the field scale. [less ▲]

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