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See detailIdentifying and computing nonlinear normal modes
Cammarano, A.; Carrella, A.; Renson, Ludovic ULg et al

in Proceedings of the SEM IMAC XXX Conference (2012, February)

Non linear normal modes offer a rigorous framework, both mathematical and physical, for theoretical and experimental dynamical analysis. Albeit still in its infancy, the concept of non linear normal modes ... [more ▼]

Non linear normal modes offer a rigorous framework, both mathematical and physical, for theoretical and experimental dynamical analysis. Albeit still in its infancy, the concept of non linear normal modes has the potential of providing to both the academic and the industrial establishment a powerful tool for the analysis of non linear dynamical systems. However, in order to exploit the full potential of this theory (and its associated simulation capability), there is need to integrate it with other branches of non linear structural dynamics: namely, in order for the non linear normal modes of a real - physical - structure to be computed, there is need to identify and quantify its non linearity. In this paper, an identification method based on the measured Frequency Response Function (FRF) is employed to identify and quantify the system's non linearity before computing the system's non linear normal modes. [less ▲]

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See detailIdentifying and modeling the integrated design process of net Zero Energy buildings
Attia, Shady ULg; Walter, Emmanuel; Andersen, Marilyne

in Proceedings of the High Performance Buildings - Design and Evaluation Methodologies Conference (2013, June)

High Performance Buildings (HPB), including Net Zero Energy Buildings (NZEBs) and nearly Zero Energy Buildings (nZEB) are emerging as an important market in Europe and around the world. However, there are ... [more ▼]

High Performance Buildings (HPB), including Net Zero Energy Buildings (NZEBs) and nearly Zero Energy Buildings (nZEB) are emerging as an important market in Europe and around the world. However, there are very few studies that aim to model the process of HPBs and define key design processes, decisions and competencies of design teams. More importantly, there is hardly any documentation processes on tools currently being used to design high performance building. Therefore, the purpose of this paper is to identify, model and propose a generic integrated process maps for HPB. The generic process map focuses on the design phases steps, roles and tools used. The research methodology is based on literature review and a case study. With the help of a process modelling software (TIBCO), a Swiss office building (Green Office) is used to validate the produced process maps. The visual maps delivers insights on the integrated design process reporting on the means of improving the delivery of HPBs. [less ▲]

Detailed reference viewed: 188 (4 ULg)
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See detailIdentifying beneficiaries of poverty alleviation programs
Mai, Lan Phuong ULg; Nguyen Mau, Dung; Lebailly, Philippe ULg

in Economics and Development Review = Kinh té̂ và phát triẻ̂n (2011), Special issue(July 2011), 29-36

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See detailIdentifying codes in vertex-transitive graphs
Gravier, Sylvain; Parreau, Aline ULg; Rottey, Sara et al

Conference (2014, July)

We consider the problem of computing identifying codes of graphs and its fractional relaxation. The ratio between the optimal integer and fractional solutions is between 1 and 2 log(|V|) where V is the ... [more ▼]

We consider the problem of computing identifying codes of graphs and its fractional relaxation. The ratio between the optimal integer and fractional solutions is between 1 and 2 log(|V|) where V is the set of vertices of the graph. We focus on vertex-transitive graphs for which we can compute the exact fractional solution. There are known examples of vertex-transitive graphs that reach both bounds. We exhibit infinite families of vertex-transitive graphs with integer and fractional identifying codes of order |V|^a with a in {1/4, 1/3, 2/5}. These families are generalized quadrangles (strongly regular graphs based on finite geometries). They also provide examples for metric dimension of graphs. [less ▲]

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See detailIdentifying codes in vertex-transitive graphs and strongly regular graphs
Gravier, Sylvain; Parreau, Aline; Rottey, Sara et al

in Electronic Journal of Combinatorics (2015), 22(4), 46

We consider the problem of computing identifying codes of graphs and its fractional relaxation. The ratio between the size of optimal integer and fractional solutions is between 1 and 2ln(|V|)+1 where V ... [more ▼]

We consider the problem of computing identifying codes of graphs and its fractional relaxation. The ratio between the size of optimal integer and fractional solutions is between 1 and 2ln(|V|)+1 where V is the set of vertices of the graph. We focus on vertex-transitive graphs for which we can compute the exact fractional solution. There are known examples of vertex-transitive graphs that reach both bounds. We exhibit infinite families of vertex-transitive graphs with integer and fractional identifying codes of order |V|^α with α∈{14,13,25}. These families are generalized quadrangles (strongly regular graphs based on finite geometries). They also provide examples for metric dimension of graphs. [less ▲]

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See detailIdentifying cows with subclinical mastitis by bulk single nucleotide polymorphism genotyping of tank milk
Blard, G.; Zhang, Zhiyan ULg; Coppieters, Wouter ULg et al

in Journal of Dairy Science (2012), 95(7), 4109-13

Mastitis remains the most important health issue in dairy cattle. Improved methods to identify cows developing subclinical mastitis would benefit farmers. We herein describe a novel method to determine ... [more ▼]

Mastitis remains the most important health issue in dairy cattle. Improved methods to identify cows developing subclinical mastitis would benefit farmers. We herein describe a novel method to determine the somatic cell counts (SCC) of individual cows by bulk genotyping a sample of milk from the milk tank with panels of genome-wide single nucleotide polymorphisms (SNP). We developed a simple linear model to estimate the contribution of individual cows to the genomic DNA present in the tank milk from 1) the known genotypes of individual cows for the interrogated SNP and 2) the ratio of SNP alleles in the tank milk. Using simulations, we estimate that 3,000, 50,000, and 700,000 SNP are sufficient to accurately (R(2)>0.98) estimate individual SCC in tanks containing milk from 25, 100, and 500 cows, respectively. Using actual data, we demonstrate that the SCC of 21 cows can be estimated with a coefficient of determination of 0.60 using approximately 9,000 SNP. The proposed method increases the value of the proposition of SNP genotyping individual cows for genomic selection purposes. [less ▲]

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See detailIdentifying early Earth microfossils in unsilicified sediments
Javaux, Emmanuelle ULg; Asael, Dan; Bekker, Andrey et al

in Geophysical Research Abstracts (2013), 15

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See detailIdentifying endophenotypes of autism: a multivariate approach
Segovia-Román, Fermín ULg; Holt, Rosemary; Spencer, Michael et al

in Frontiers in Computational Neuroscience (2014), 8

The existence of an endophenotype of autism spectrum condition (ASC) has been recently suggested by several commentators. It can be estimated by finding differences between controls and people with ASC ... [more ▼]

The existence of an endophenotype of autism spectrum condition (ASC) has been recently suggested by several commentators. It can be estimated by finding differences between controls and people with ASC that are also present when comparing controls and the unaffected siblings of ASC individuals. In this work, we used a multivariate methodology applied on magnetic resonance images to look for such differences. The proposed procedure consists of combining a searchlight approach and a support vector machine classifier to identify the differences between three groups of participants in pairwise comparisons: controls, people with ASC and their unaffected siblings. Then we compared those differences selecting spatially collocated as candidate endophenotypes of ASC. [less ▲]

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See detailIdentifying environmental risk factors for endemic cholera: a raster GIS approach
Ali, M.; Emch, M.; Donnay, Jean-Paul ULg et al

in Health & Place (2002), 8(3), 201-210

The bacteria that cause cholera are known to be normal inhabitants of surface water, however, the environmental risk factors for different biotypes of cholera are not well understood. This study ... [more ▼]

The bacteria that cause cholera are known to be normal inhabitants of surface water, however, the environmental risk factors for different biotypes of cholera are not well understood. This study identifies environmental risk factors for cholera in an endemic area of Bangladesh using a geographic information systems (GIS) approach. The study data were collected from a longitudinal health and demographic surveillance system and the data were integrated within a geographic information system database of the research area. Two study periods were chosen because they had different dominant biotypes of the disease. From 1992 to 1996 El Tor cholera was dominant and from 1983 to 1987 classical cholera was dominant. The study found the same three risk factors for the two biotypes of cholera including proximity to surface water, high population density, and poor educational level. The GIS database was used to measure the risk factors and spatial filtering techniques were employed. These robust spatial methods are offered as an example for future epidemiological research efforts that define environmental risk factors for infectious diseases. (C) 2002 Elsevier Science Ltd. All rights reserved. [less ▲]

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See detailIdentifying infectious agents from lung transplant patients using GC×GC-TOFMS
Stefanuto, Pierre-Hugues ULg; Rees, Christiaan A.; Romamno, Rosalba et al

Poster (2017, May)

During the first year post-surgery, bacterial and fungal infections are the main causes of death in lung transplant recipients. Contributing substantially to the high mortality rate (35%) is the lengthy ... [more ▼]

During the first year post-surgery, bacterial and fungal infections are the main causes of death in lung transplant recipients. Contributing substantially to the high mortality rate (35%) is the lengthy time-to-diagnosis, which includes both pathogen identification and antibiotic resistance profiling. A novel diagnostic strategy based on the detection of volatile compounds in breath seems a promising option to improve these patients’ outcomes. In order to demonstrate the feasibility of this approach, we characterized the volatile fraction of different clinical matrices (i.e., bronchoalveolar lavage (BAL) and blind bronchial aspirate (BBA)). Due to the complexity of the mixture and high dynamic range of the concentrations, we applied headspace solid phase microextraction (HS-SPME) combined with comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry (GC×GC-TOFMS) to obtain a comprehensive overview of the sample headspace composition. Following the analytical step, we applied various univariate and multivariate statistical methods (e.g. random forest, principal component analysis, and hierarchical cluster analysis) in order to extract required information from the data. Based on the composition of the volatile fraction, we were able to differentiate between BAL and BBA with a classification accuracy of 88.4 %. Furthermore, we could correctly distinguish between individuals with active respiratory infections and those without infection with a 72.2 % classification accuracy. In some cases, it was also possible to differentiate between pathogens at the species level. These results are preliminary evidence to suggest the possibility of detecting infections in these patient without the use of time-consuming culture techniques. [less ▲]

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See detailIdentifying Inflammatory Bowel Disease causative genes through trans-eQTLs mapping within GWAS loci
Docampo Martínez, Elisa ULg; Theatre, Emilie ULg; Dmitrieva, Joelia Borisnova ULg et al

Poster (2014, April 24)

Lifetime prevalence of inflammatory bowel disease (IBD) is reaching an alarming rate of >1/400 in industrialized societies. Improved understanding of disease pathogenesis is essential to develop more ... [more ▼]

Lifetime prevalence of inflammatory bowel disease (IBD) is reaching an alarming rate of >1/400 in industrialized societies. Improved understanding of disease pathogenesis is essential to develop more effective preventive, diagnostic and therapeutic measures. Genome-wide association studies (GWAS) have identified ~ 160 risk loci contributing to inherited predisposition to IBD, leading to the identification of new perturbed pathways and potential drug targets. Nevertheless, causative genes and variants remain unknown for the vast majority of risk loci. GWAS loci are likely to be regulatory and therefore alter expression levels of other genes. We hypothesize that if an IBD associated SNP is an expression quantitative loci (eQTL)-the " disease-association pattern " (DAP) should mirror the " eQTL association pattern " (EAP) of the causative gene if looking in the right target tissue(s). With this premise, our project aims to detect causative genes implicated in IBD's susceptibility through the evaluation of trans-eQTLs within GWAS loci. To this purpose, nine blood cell types and ileal, colonic and rectal biopsies have been collected for 330 healthy individuals of Northern European descent. All individuals have been genotyped with the OmniExpress Illumina array interrogating > 700K genetic variants. Transcriptome analysis has been conducted for all individuals and all cell/tissue types using Illumina HT12 arrays interrogating > 47,000 transcripts. Genotype and transcriptome data have undergone rigorous quality control. Transcriptome data have been pretreated variance stabilizing transformation, QQ normalization and correction for random and fixed effects in each cell type. Only expression probes mapped against Refseq have been considered. Genomic positions have been recovered and probes mapping to more than one genomic position (taking into account splice junctions with Tophat software) with a 96% identity have been discarded. Trans-eQTL mapping will be conducted on a SNP-by-SNP basis using linear regression (additive model) with PLINK software. In order to circumvent genome wide multiple testing penalty, we will test for a given SNP in the genome, any evidence for an excess of low p-values when testing its effect on the expression of genes located on other chromosomes or far away on the same chromosome. Confirmation of putative multigene transregulators will afterwards be performed by RNAseq experiments. We will then quantify the resemblance between DAP in the 160 GWAS-identified risk loci (raw data from IIBDGC plus imputed data) and " multigene trans-EAP " with Spearman's rank correlation. We will also evaluate the biological relevance of this list by performing a network analysis after adding the identified trans targets to the list of previously identified positional candidate genes (mapping to GWAS-identified IBD risk loci). Finally, as a the ultimate proof of causality, the selected genes will be resequenced in 3,000 IBD cases and 3,000 controls, using 600 DNA pools of 10 individuals with Illumina Truseq Amplicon. With this strategy, we expect to detect new causative variants that may constitute new drug targets for IBD. Latest results will be presented. [less ▲]

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See detailIdentifying Late Egyptian Virtual Relative Clauses
Sojic, Nathalie ULg

Conference (2016, February 19)

Ancient Egyptian so-called "virtual" relative clauses (VRC) are adverbial clauses that function like relative clauses. Descriptions provided by Late Egyptian grammars inform students of their existence ... [more ▼]

Ancient Egyptian so-called "virtual" relative clauses (VRC) are adverbial clauses that function like relative clauses. Descriptions provided by Late Egyptian grammars inform students of their existence and provide some translational devices. But they are not sufficient to describe the Late Egyptian relativization system in a linguistic perspective. The talk, given on the occasion of the international Crossroads V conference, aimed at providing interpretive guidelines based on syntax, pragmatics and discourse analysis. In my communication, I showed that discourse analysis proved to be very fruitful in clarifying some contexts of use of LEg VRCs as well as some interpretive processes. [less ▲]

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See detailIdentifying losses and expansions of selected gene families in incomplete genomic datasets
Di Franco, Arnaud ULg; Hanikenne, Marc ULg; Baurain, Denis ULg

Poster (2013, December 09)

Plantae (Archaeplastida) are a natural group of organisms with plastids of primary endosymbiotic origin. Within this group, members of the red algae show evidence of a reduction of their genomic content ... [more ▼]

Plantae (Archaeplastida) are a natural group of organisms with plastids of primary endosymbiotic origin. Within this group, members of the red algae show evidence of a reduction of their genomic content. In this work, we designed a bioinformatics approach to investigate the few, sometimes incomplete, genomic datasets available for red algae, with the purpose of pointing out possible gene family losses and expansions. Our pipeline first populates a relational database with precomputed orthology relationships between green plant genomes and red algal datasets and then efficiently queries the database for computing statistics of losses and expansions for a series of gene families of interest. [less ▲]

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See detailIdentifying mismatch between urban travel demand and transport network services using GPS data: A case study in the fast growing Chinese city of Harbin
Cui, JianXun; Liu, Feng; Hu, Jia et al

in Neurocomputing (2016), 181

The world's urban population growth and economic development have led to the reshaping of metropolitan space layouts among residential, employment and shopping locations, generating growing mismatch ... [more ▼]

The world's urban population growth and economic development have led to the reshaping of metropolitan space layouts among residential, employment and shopping locations, generating growing mismatch between travel demand and transport services. A reliable method to accurately analyze mobility demand and underlying transport network systems and to identify areas with serious mismatch problems is important for the design of effective policy measures. In this paper, we make use of the wide deployment of GPS devices in vehicles in many cities today, to develop such a method. This approach is developed using GPS data collected from all taxis operating in the Chinese city of Harbin between July and September in 2013. It consists of four major steps. First, city-wide mobility patterns are modeled based on GPS trajectories. This model captures a set of key traffic characteristics for each pair of regions in the entire urban network, including travel demand, travel speed and route directness of travel paths. From this model, a set of indicators is then built to measure the road transport performance between the regions, and the areas with serious mismatch problems are subsequently pinpointed. Finally, the identified problematic regions are further examined and specific transport problems are analyzed. By applying the proposed method to the city of Harbin, the potential and effectiveness of this method are demonstrated. Moreover, with more and more urban vehicles being equipped with GPS devices, the designed method can be easily transferred to other cities, thus paving a way for the adoption of the presented approach for an up-to-date and spatial-temporal sensitive road network analysis approach that supports the establishment of a more sustainable urban transport system. [less ▲]

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See detailIdentifying novel biomarkers for the rapid diagnosis of invasive aspergillosis using GC×GC-TOFMS
Stefanuto, Pierre-Hugues ULg; Rees, Christiaan A.; Beattie, Sarah R. et al

Conference (2017, May)

Aspergillus fumigatus is a filamentous fungus responsible for the life-threatening infection, invasive aspergillosis (IA), in immunocompromised individuals. Currently, IA diagnostic methods take days to ... [more ▼]

Aspergillus fumigatus is a filamentous fungus responsible for the life-threatening infection, invasive aspergillosis (IA), in immunocompromised individuals. Currently, IA diagnostic methods take days to produce a result and methods to obtain samples are invasive. One approach to improve the time-to-diagnosis is based on utilizing our knowledge of fungal metabolism during pathogenesis. Recent studies have demonstrated the importance of oxygen availability during IA, which presents a potential diagnostic opportunity. In this study, we analyzed the early (1 hr) and late (8 hr) volatile profile of A. fumigatus strain CEA1o under oxygen replete (~20% O2) and deplete (0.2% O2) conditions. In order to comprehensively screen the headspace of these cultures, we applied headspace solid phase microextraction (HS-SPME) associated with comprehensive two-dimensional gas chromatography coupled to time of flight mass spectrometry (GC×GC-TOFMS). Comparing the headspace of the four culture conditions, we were able to identify specific volatile biomarkers of low oxygen fungal growth: ethanol, acetaldehyde, 2-propanol, 2,3-butanedione, and 3-hydroxy-2-butanone. Based on the putative identifications of these compounds, we identified potential metabolic pathways that are responsible for their production. The two first compounds are known to be produced during hypoxia metabolism of glucose, however, the three others suggest that previously uncharacterized metabolic pathways may be utilized by A. fumigatus in low oxygen conditions. Validation of these biomarker identities and translation into patients may generate metabolic insight into these organisms during IA pathogenesis. [less ▲]

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See detailIdentifying plausible cascading events in system stability assessment
Otomega, Bogdan; Van Cutsem, Thierry ULg

in Proc. 3rd International Conference on Energy and Environment (CIEM2007) (2007, November)

An implementation of the event tree approach is proposed to determine possible sequences of cascading failures with severe impact on a given power system. The algorithm takes into account protection ... [more ▼]

An implementation of the event tree approach is proposed to determine possible sequences of cascading failures with severe impact on a given power system. The algorithm takes into account protection systems hidden failures and transmission system equipments overload. At each level of the event tree development, the sequence probability order is computed and a filtering tool is used to identify possible harmful sequence. These are furthermore analysed with a time domain simulation tool in order to assess their impact on the power system. This paper contains the description of the event tree algorithm as well as examples of its practical application on the Nordic32 test system. [less ▲]

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See detailIdentifying root-secreted proteases in Arabidopsis thaliana: an Activity-Based Protein Profiling approach.
Lallemand, Jérôme ULg; Périlleux, Claire ULg; Tocquin, Pierre ULg

Poster (2014, May 15)

Proteases are involved in many physiological processes during the whole life of the plant, such as embryonic development, defense against pathogens, nutrition or mycorrhiza creation. However, the ... [more ▼]

Proteases are involved in many physiological processes during the whole life of the plant, such as embryonic development, defense against pathogens, nutrition or mycorrhiza creation. However, the functions of many of the 800 proteases of Arabidopsis thaliana still remain unknown. Besides discovering new functions, studying proteases can also result in improving plant biotechnology. Indeed, plants can be used as hosts for recombinant protein production. Some proteins of interest require to be secreted in order to fold properly, but production yields are limited due to their degradation by endogenous extracellular proteases. The aim of our study is to identify active root-secreted proteases of Arabidopsis thaliana. Their activity was first analyzed by in vitro incubation with a target protein (BSA) at different values of pH and in the presence of proteases inhibitors. This analysis identified serine proteases as the major protease class involved in BSA degradation. Then, an Activity-Based Protein Profiling approach led to the labeling of two active serine proteases in the root-secreted sample. Finally, a further step towards the identification by mass spectrometry, based on affinity purification, was developed. [less ▲]

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See detailIdentifying seepage in ditches and canals in ploders in \textscThe \textscNetherlands by distributed temperature sensing
Hoes, O. A. C.; Luxemburg, W. M. J.; Westhoff, Martijn ULg et al

in Lowland Technology International (2009), 11(2), 21-26

Seepage in ditches and canals, a common feature in polders in The Netherlands, is investigated making use of temperature sensing by fiber optic cable. By its high spatial and temporal resolution ... [more ▼]

Seepage in ditches and canals, a common feature in polders in The Netherlands, is investigated making use of temperature sensing by fiber optic cable. By its high spatial and temporal resolution capabilities the technique reveals the complex ensemble of all effects that define the water temperature on the bottom of the watercourses in three polders where a 1300 meter long cable was located. From the temperature signature the location of suspected seepage zones in the water courses can be determined more precisely. The study shows that the sensing of seepage through temperature is time dependent as the signature can temporarily fade and can be extremely localized. This shows the potential for the applied technique. [less ▲]

Detailed reference viewed: 12 (1 ULg)