Recent advances on aphid alarm pheromone biosynthetic pathway

Conference (2013, June)

Maladie hémolytique néonatale modérée due à un anti‐RH46

Poster (2013, June)

Optimisation robuste de méthodes SFC par une approche de type design space

Conference (2013, June)

The contributions of pairs of parallel surfaces in a simple analytical model of room reverberation

in I.C.A. (Ed.) Proceedings of the 2013 ICA Congress (2013, June)

Parapet wall effect on Piano Key Weirs efficiency

in Journal of Irrigation & Drainage Engineering (2013), 139(6), 506-511

Piano Key Weir is a cost effective solution for rehabilitation as well as for new dam projects with a high level of constraints (limited space, high specific flood discharge, small reservoir level ... [more ▼]

Piano Key Weir is a cost effective solution for rehabilitation as well as for new dam projects with a high level of constraints (limited space, high specific flood discharge, small reservoir level variation). While the higher efficiency of the Piano Key Weir compared to standard linear weirs has already been demonstrated, its optimal geometry is still poorly defined. In order to improve the design of the complex geometry of this structure, the use of parapet walls has been tested. They consist of vertical extensions placed over the weir crest. Following a former study of the influence of the weir height on its discharge capacity, this paper presents the results of an experimental campaign dedicated to investigating the effect of parapet walls to increase weir height while reducing bottom slopes and keeping the weir height constant. These results indicate the relative influences of the alveoli bottom slopes and of the weir height on the Piano Key Weir release capacity. Comparisons with former experimental results as well as design guidelines are also provided. [less ▲]

Biomass hydrolyzing enzymes identified by functional screening of a metagenomic library from algal biofilms.

Poster (2013, June)

Biomass hydrolyzing enzymes are increasingly searched for the production of biofuels and renewable chemical compounds using biomass. Microorganisms living on algaes are an interesting reservoir of biomass ... [more ▼]

Biomass hydrolyzing enzymes are increasingly searched for the production of biofuels and renewable chemical compounds using biomass. Microorganisms living on algaes are an interesting reservoir of biomass hydrolyzing enzymes, as they are in constant interaction with algal biomass. Therefore, we are interested in looking for some of those enzymes synthesized by the microflora living on the surface of the brown algae Ascophyllum nodosum. Algae samples were collected in the winter 2012 and a microbial DNA extraction method was developed. The whole extracted microbial genomes of the microorganisms living on the algae were restricted, inserted in a cloning vector and ligated products were used for transformation of cultivable Escherichia coli host cells. This metagenomic library was then screened for diverse enzymatic activities (lipolytic enzymes, cellulases, beta-glucosidases, alpha-amylases, arabinanases, xylanases and proteases) on agar plates with specific substrates. Five putative lipolytic enzymes, one cellulase and one beta-glucosidase were identified. Sequence analysis revealed low (<50%) sequence identities with known enzymes sequences, meaning new enzymes from unknown genomes have been discovered. To our knowledge this is the first functional screening that was realized with a metagenomic library from algal biofilms and this is the first cellulase identified by marine metagenomics. A second library has been constructed from algae sample from summer 2012 and is currently being screened. New enzymatic tests are being developed for the identification of enzymes degrading specific algal polysaccharides like agarases, carrageenases, alginate lyases, laminarinases,… Those very specific enzymes aren’t well known yet, and our metagenomic approach will probably help us to identify new families and structures of those algal biomass hydrolyzing enzymes. [less ▲]

Etude prospective des caractéristiques hématologiques, biochimiques et urinaires du Dogue de Bordeaux: Une race prédisposée à une glomérulopathie familiale

Doctoral thesis (2013)

Dogue de Bordeaux (DDB) dogs are predisposed to a juvenile glomerulonephropathy (JGN), usually leading to an end-stage chronic kidney disease (CKD), mostly before 2 years of age. Since its first ... [more ▼]

Dogue de Bordeaux (DDB) dogs are predisposed to a juvenile glomerulonephropathy (JGN), usually leading to an end-stage chronic kidney disease (CKD), mostly before 2 years of age. Since its first description a few years ago, the number of DDB dogs diagnosed with JGN has drastically increased in Europe. Furthermore, some DDB dogs might develop clinical signs far later than initially thought. As the mode of inheritance of this condition has not yet been elucidated, an early diagnosis of JGN is of central importance for breeders and owners. To ease screening of affected dogs, we first wanted to improve our knowledge of this ancient French breed by describing characteristics of healthy DDB dogs. Given available information, we indeed suspected that some biological specificity existed in this breed, which could affect diagnostic processes and lead to erroneous clinical decisions. We thus determined, in a first study, breed-specific biochemical and hematological reference intervals (RI). For most of the 29 measured biochemical analytes, using the manufacturer’s generic canine RI would not have had a major clinical impact, however breed-specific RI established for 6 of them were relevantly different. Limits of the RI for total proteins, total cholesterol, aspartate aminotransferase, alanine aminotransferase and lipase were higher, while they were markedly lower for total thyroxin. Among the 25 hematological RI that were determined and compared with generic canine RI established in the same laboratory, only those of some red blood cells and platelet indices were sufficiently different to have a significant impact on clinical decision. Most red blood cells indices had higher, whereas most platelet indices had lower RI. As we also hypothesized that some apparently healthy adult DDB could suffer from JGN, we decided to look, in a second study, for the biological abnormalities that were previously described in association with the disease. We thus recruited a large cohort of adult DDB and found that proteinuria (urine protein-to-creatinine ratio (UPC) > 0.5) was present in 33%, and proteinuric CKD in 2% of the dogs. When assessed by UPC, proteinuria increased with age and was associated with changes in several biological variables. Urine specific gravity, plasma albumin and total calcium decreased, whereas cholesterol, fibrinogen and thyroid-stimulating hormone increased with UPC. Furthermore, changes in total renal volume, evaluated by ultrasound, were also described to be affected by magnitude of proteinuria. Having a UPC>0.5 increased the probability of observing urinary granular casts by an odds-ratio of 4. Amplitude of biological variations observed in this study was however generally moderate. Finally, to investigate if proteinuric DDB could be suffering from a glomerular disease related to the JGN, we attempted in a third study to characterize the nature of their proteinuria. For that purpose, we used urinary proteins electrophoresis and specific tubular (retinol binding protein (uRPB) and N-acetyl-β-D-glucosaminidase (uNAG) enzyme) and glomerular (albumin (uAlb) and immunoglobulins G (uIgG)) urinary markers. One hundred and two DDB, including 2 dogs with proteinuric CKD, were retrospectively recruited for this study, irrespective of UPC values, to facilitate comparison. Final interpretations of urine proteins electrophoresis attributed a “normal” pattern to 39 dogs, a tubular pattern to 9 of them, a glomerular pattern to 38, and a mixed pattern to 16. Most of these results were highly correlated to UPC values. However, tubular and mixed patterns were only attributed to entire male dogs because of the presence of an isolated 25kDa band, which might be due to urinary contamination by seminal proteins. When results for urinary markers were compared to values obtained in non proteinuric (UPC≤0.2) DDB dogs, 37% of the borderline proteinuric dogs (0.2≤UPC<0.5) had all four markers within reference limits. On the other hand, all proteinuric DDB dogs had elevated ratios of uAlb and uIgG when their concentrations were related to urinary creatinine (/c). Only 53% of them had an elevated uRBP/c and 35% an elevated uNAG/c, which corresponded to the dogs with highest UPC values. Results of this last study support the hypothesis that proteinuric DDB dogs have a glomerular disease which is likely related to JGN. Additionally, sensitivity, specificity, positive and negative likelihood ratio of electrophoresis to identify dogs with elevated uAlb/c were 94%, 92%, 11.85 and 0.07, in that order. These indices were respectively 90%, 74%, 3.43 and 0.13, to identify DDB dogs with abnormally elevated uIgG/c. [less ▲]

Le potentiel du saule pour la phytostabilisation des sols pollués par les éléments-traces métalliques

Doctoral thesis (2013)

Since the ‘80s, when the concept of phytoremediation first appeared, a lot of research has been put into studying the efficiency of woody plants in metal extraction. Willows, as fast growing plants and ... [more ▼]

Since the ‘80s, when the concept of phytoremediation first appeared, a lot of research has been put into studying the efficiency of woody plants in metal extraction. Willows, as fast growing plants and because of their tolerance to difficult edaphic conditions, have been particularly well investigated. In this investigation, the essays were done on Salix clones, which come from a Walloon collection provided by ECOLIRI and ECOLIRIMED projects. The first objective was to study the potential of these local clones by considering not only their ability to extract their pollutants, but also by adding their biomass production to this parameter. We have called the study of these criteria the phenotypic approach to the tolerance of Salix clones to metals. The second added value of this investigation lies in the second objective which aims to complete these phenotypic criteria with physiological and proteomic criteria. These last criteria are often used to study the metal tolerance of plant species, but rarely for willows. The combination of these different approaches gives a expand view of metal tolerance in Salix clones studied in this investigation. As the phenotypical parameters help to answer the extraction ability challenge, the physiological and proteomic approaches give answers linked to the “health” of the willow trees when they grow in the presence of metals. Our results indicate that the clones that produced more biomass were the ones that showed the highest metal concentrations. The clones with lower biomass production showed the same tolerance as the highest producers and our results revealed that growth reduction indicates metal tolerance. Finally, after comparing our results of the metal concentrations obtained in the twigs, to results obtained during the last two decades of research papers, we have concluded that we should reconsider the use of Salix potential in phytoextraction. The first chapter of this investigation was about Salix clones exposed to metals, but, in natural conditions, their roots are colonized by fungi. Thus, their rhizosphere constitutes a separate ecosystem, which is interesting to investigate. The rhizospheric fungi, the first interface between roots and soil pollutants, play an important role in metal tolerance in woody plants. For this reason, the second chapter of this thesis aimed to test the in vitro growth of rhizospheric fungi collected on woody plant roots in the presence of cadmium. The outcome of these essays is that fungal strains have been identified and classified as tolerant to this metal. This chapter thus constitutes a first step in a future study aiming to analyze these strains in association with woody plant roots in the presence of metals. [less ▲]

Workers expectations in flexibility and employment security: a qualitative approach

Conference (2013, May 28)

Hygrothermal behavior modeling of different Lime-Hemp Concrete mixes

Conference (2013, May 27)

This paper studies the specific hygrothermal behavior of Lime-Hemp concretes through analysis of non-linear coupled heat and moisture transfer using a research model. Three compositions were studied ... [more ▼]

This paper studies the specific hygrothermal behavior of Lime-Hemp concretes through analysis of non-linear coupled heat and moisture transfer using a research model. Three compositions were studied, varying the type of binder. First Moisture Buffer Value determination tests are lead experimentally using the NORDTEST protocol. These dynamic experiments, which reveal the moisture storage and exchange capacity together with latent heat effects, are then modeled using a set of partial differential equations. The reduction of humidity buffering capacity induced by hydraulic binder incorporation is properly evaluated and the hygrothermal parameters can be assessed by inverse modeling. [less ▲]