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See detailSystematic analysis of site-specific yield distributions resulting from nitrogen management and climatic variability interactions
Dumont, Benjamin ULg; Basso, Bruno; Leemans, Vincent ULg et al

in Precision Agriculture (2015), 16(4), 361-384

At the plot level, crop simulation models such as STICS have the potential to evaluate risk associated with management practices. In nitrogen (N) management, however, the decision-making process is ... [more ▼]

At the plot level, crop simulation models such as STICS have the potential to evaluate risk associated with management practices. In nitrogen (N) management, however, the decision-making process is complex because the decision has to be taken without any knowledge of future weather conditions. The objective of this paper is to present a general methodology for assessing yield variability linked to climatic uncertainty and variable N rate strategies. The STICS model was coupled with the LARS-Weather Generator. The Pearson system and coefficients were used to characterise the shape of yield distribution. Alternatives to classical statistical tests were proposed for assessing the normality of distributions and conducting comparisons (namely, the Jarque-Bera and Wilcoxon tests, respectively). Finally, the focus was put on the probability risk assessment, which remains a key point within the decision process. The simulation results showed that, based on current N application practice among Belgian farmers (60 60 60 kgN ha-1), yield distribution was very highly significantly non normal, with the highest degree of asymmetry characterised by a skewness value of -1.02. They showed that this strategy gave the greatest probability (60%) of achieving yields that were superior to the mean (10.5 t ha-1) of the distribution. [less ▲]

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See detailOpérations militaires : entre prise de risque, solidarité, souveraineté et "entrée en premier"
Dumoulin, André ULg

in Sécurité & Stratégie (2015), (201),

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See detailNiche-innovations between breaks and continuities with the regime? A case study into the dairy sector in Belgium
Feyereisen, Marlène ULg; Melard, François ULg; Stassart, Pierre M ULg

Conference (2015, August)

Today, the absolute dichotomy between alternative food networks (AFNs) and the conventional agrofood system tends to be obsolete. Indeed, many AFNs are far from being radical and are more likely to ... [more ▼]

Today, the absolute dichotomy between alternative food networks (AFNs) and the conventional agrofood system tends to be obsolete. Indeed, many AFNs are far from being radical and are more likely to maintain relations with the current socio-technical regime between breaks and continuities. This contribution is a complement to the Transition Theory and the Multi-Level Perspective by underlying the fragile borders between the two levels of the niche-innovations and the socio-technical regime: some imperfect projects, full of contradictions, are participating to the transition of the system. And this is particularly true in the case of highly locked in systems. The dairy sector in Western European countries is one of those highly locked in systems. Our case study, the Belgian fair-trade milk “Fairebel”, is a project built by dairy farmers to react to the 2009 dairy crisis and to the increasingly neoliberal dairy sector; and to get a better price (or fair price) for their activity. However, the concretization of this project brought its share of contradictions regarding the common definition of fair trade milk. As a result, the “Fairebel” project maintains relations between breaks and continuities with the regime. This contribution suggests modes of governance for the stakeholders of these non-radical niches which are precious to engage change in highly locked in system without being picked up by the dominant regime and thus, keep this regime under pressure. [less ▲]

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See detailLa lutte contre les moustiques (Diptera: Culicidae): diversité des approches et application du contrôle biologique
Bawin, Thomas ULg; Seye, Fawrou; Boukraa, Slimane ULg et al

in Canadian Entomologist (2015), 147(4), 476-500

Many mosquito (Diptera: Culicidae) species are zoonotic vectors responsible for numerous infectious diseases of medical and veterinary importance. Currently, changes in the vectors’ geographical ... [more ▼]

Many mosquito (Diptera: Culicidae) species are zoonotic vectors responsible for numerous infectious diseases of medical and veterinary importance. Currently, changes in the vectors’ geographical distribution induced chiefly by anthropogenic factors are accompanied by emerging and reemerging infectious diseases in Europe and North America. Since the advent of synthetic insecticides during the Second World War, mosquitoes are the object of considerably expanded and deepened research. In an integrated pest management context, means of control are now mainly classified as: (1) environmental management and physical control, (2) chemical control, (3) genetic control, and (4) biological control by means of entomophagous predators and entomopathogenic microorganisms. In this context, these last have significant potential because of their ability to infect and kill their host with more or less targeted selectivity. This article proposes to emphasize biological control among other techniques in mosquito control, and to assess the potential and the opportunities offered by entomopathogenic bacteria, viruses and fungi. Finally, their use as biopesticides is discussed. [less ▲]

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See detailStudies of nebulae ejected from massive stars based on observations with the Herschel space observatory
Vamvatira-Nakou, Chloi ULg

Doctoral thesis (2015)

This PhD thesis is devoted to the study of the nebulae ejected by the luminous blue variable (LBV) stars WRAY 15-751 and AG Car as well as by the Wolf-Rayet star WR 124. It is based on new infrared data ... [more ▼]

This PhD thesis is devoted to the study of the nebulae ejected by the luminous blue variable (LBV) stars WRAY 15-751 and AG Car as well as by the Wolf-Rayet star WR 124. It is based on new infrared data taken by the Herschel Space Observatory. These data were complemented by optical data as well as by archived infrared observations. In the first chapter, a general introduction to the subject is given along with a description of the methods used for the data analysis. The three following chapters contain the study of each one of the three nebulae separately. This led to the determination of the physical parameters of the dust and gas components, with the aim to shed a new light on the mass-loss history of the central stars. In particular, the new Herschel infrared images provide a detailed mapping of the nebular dust distribution and of the circumstellar environment at different scales, revealing multiple shells and cavities linked to previous mass-loss events. Moreover, the combination of Herschel photometric results along with archival data was used to model dust with the help of a two-dimensional publicly available radiative transfer code. This model provided us with the dust mass, temperature and composition. The Herschel infrared spectra of all nebulae revealed forbidden nebular emission lines coming not only from an ionized gas region but also from a region where the gas is neutral. Based on the emission line flux measurements, the gas mass and the abundance ratios were estimated. These results, combined with the theoretical models of stellar evolution, were then used to constrain the evolutionary stage of the star at which each nebula was ejected. This study underlines the importance of the Herschel infrared observations for these nebulae. Thanks to them, a better understanding of these objects has been achieved. In particular, a second bigger and fainter dust shell was discovered around WRAY 15-751. In addition, all nebulae were found lying in empty cavities, probably formed during a previous evolutionary phase of their central star. The dust models indicated the necessity to include large grains in all nebulae to reproduce the data. This study showed that for the LBV WRAY 15- 751, with an initial mass of 40 M sun, the nebular ejection took place during a red supergiant phase, while for the LBV AG Car, with an initial stellar mass of 55 M sun, the ejection happened during a cool LBV phase. For the nebula M1-67 around the star WR 124, with an initial mass of 60 M sun, the ejection also took place during a LBV phase. These results are in agreement with the current evolutionary models with little stellar rotation. [less ▲]

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See detailThe effects of triclosan exposure in shape changes of sheepshead minnow (Cyprinodon variegatus) during early development and metamorphosis
Schnitzler, Joseph ULg; Frederich, Bruno ULg; Dussenne, Mélanie et al

Conference (2015, August)

Thyroid hormones are essential for normal development, and for maintenance of normal physiological functions in vertebrates [1, 2]. In fish, thyroid hormones are involved in the control of osmoregulation ... [more ▼]

Thyroid hormones are essential for normal development, and for maintenance of normal physiological functions in vertebrates [1, 2]. In fish, thyroid hormones are involved in the control of osmoregulation, metabolism, somatic growth and post-hatching metamorphosis [1, 3, 4]. The regulation of thyroid hormone bioavailability in tissues and cells represents a very complex and unique web of feedback systems [2]. In fish and other vertebrates the thyroid cascade involves two components. First, thyroxine (T4) biosynthesis and secretion are largely under central control by the brain–pituitary–thyroid axis [5]. Second, there is the conversion of T4 to its biologically active form 3,5,3-triiodothyronine (T3) and its metabolism and receptor-mediated actions that seems largely to be under peripheral control in extra-thyroidal tissues [6]. The accumulation in the aquatic environment of anthropogenic chemicals, among which are endocrine disrupting chemicals (EDCs) that alter normal hormonal regulation, is having dramatic consequences for humans and wildlife. Numerous chemicals disrupt thyroid homeostasis affecting thyroid hormone (TH) synthesis and transport, and cellular uptake and metabolism [7, 8]. Triclosan (TCS) is a synthetic chlorinated phenolic compound with a generalized use as an antimicrobial and preservative in many personal care and household products [9-11]. As a result of disposal of TCS through sewage systems and insufficient/variable removal by wastewater treatment plants (WWTP) [9], widespread contamination with TCS has been detected in several countries, particularly in aquatic ecosystems, WWTP influents and effluents; sludges and biosolids; surface or ground water; drinking water; and aquatic sediments [9-11]. TCS and its metabolites have been detected in tissues and body fluids of aquatic organisms including fish, revealing they are accumulating in the food chain [9-11] and TCS has also been detected in human blood, breast milk and urine [9-11]. The structural similarity of TCS with THs [9] suggest it may have adverse effects on the thyroid system. However, little is known about the mechanisms by which TCS disrupts the thyroid axis. TCS effects on fish thyroid axis have not been investigated. It is possible, that the TCS toxic effects reported in fish embryos, larvae and adults [9-11] might be caused, at least in part, through its effect on the thyroid system. We determined how TCS affect ontogenic variations of thyroid hormones in developing sheepshead minnow larvae. Knowing that thyroid hormones are involved in somatic growth and post-hatching metamorphosis, we also tested the hypothesis that TCS alter the development of these larvae. To do this, we used landmark-based geometric morphometric methods. These methods allowed us to analyse the pure shape variations of our developing larvae, regardless orientation, position, and size. [less ▲]

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See detailDo Triclosan affect hearing development of Cyprinodon variegatus larvae?
Schnitzler, Joseph ULg; Benichou, Farida; Pinte, Nicolas et al

Poster (2015, August)

The aquatic environment represents the final sink for many chemicals, including bactericidal agents. Among them Triclosan (TCS) has been shown to affect the thyroid system of teleost. Larval stages are ... [more ▼]

The aquatic environment represents the final sink for many chemicals, including bactericidal agents. Among them Triclosan (TCS) has been shown to affect the thyroid system of teleost. Larval stages are particularly vulnerable to deleterious effects of endocrine disrupters because of potential impairment of fish development and behaviour. Thyroid hormones are critical to the development of the brain and auditory system. Thus, TCS could affect the development of the brain and hearing. The aims of this study were: to investigate hearing development in sheepshead minnows (Cyprinodon variegatus) using the ABR technique (Auditory Brainstem Response) and to investigate the effects of triclosan on hearing development. Exposure to TCS was conducted from fertilization of eggs on at concentrations likely to be found in the environment: 20, 50 and 100 µgl-1. We characterized previously the ontogenic variation of thyroid hormones in embryos and larvae of sheepshead minnows. We observed an increase of thyroid hormones level around the 12th and the 15th day post hatching (dph), that may be associated with the transition from larval to juvenile stage during the development of this species. We concluded, that this period could be defined as a critical exposure window to pollutants. We determined hearing thresholds for sheepshead minnows of different ages. Our sheepshead minnows show ontogenic variations in the hearing ability during their development. At 30 days post hatching, their hearing ability is quite bad, with a narrow bandwidth of detected frequencies. But their hearing ability considerably enhance during their development to reach the adult hearing ability at around 80 days post hatching when this species reach sexual maturity. So we observe during the developmental phase of this fish species clear ontogenic improvements of the hearing ability and they showed an ontogenetic expansion in the frequency bandwidth they were able to detect. The effects of TCS in this development have yet to be determined but will be fully discussed. This study proposes an interesting new endpoint in thyroid disruption research. [less ▲]

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See detailPerformance, robustness and sensitivity analysis of the nonlinear tuned vibration absorber
Detroux, Thibaut ULg; Habib, Giuseppe ULg; Masset, Luc ULg et al

in Mechanical Systems & Signal Processing (2015), 60-61

The nonlinear tuned vibration absorber (NLTVA) is a recently developed nonlinear absorber which generalizes Den Hartog׳s equal peak method to nonlinear systems. If the purposeful introduction of ... [more ▼]

The nonlinear tuned vibration absorber (NLTVA) is a recently developed nonlinear absorber which generalizes Den Hartog׳s equal peak method to nonlinear systems. If the purposeful introduction of nonlinearity can enhance system performance, it can also give rise to adverse dynamical phenomena, including detached resonance curves and quasiperiodic regimes of motion. Through the combination of numerical continuation of periodic solutions, bifurcation detection and tracking, and global analysis, the present study identifies boundaries in the NLTVA parameter space delimiting safe, unsafe and unacceptable operations. The sensitivity of these boundaries to uncertainty in the NLTVA parameters is also investigated. [less ▲]

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See detailPhysical modeling of lateral dike breaching due to overtopping
Rifai, Ismail; Erpicum, Sébastien ULg; Archambeau, Pierre ULg et al

in River, Coastal and Estuarine Morphodynamics, RCEM 2015 (2015, August)

Dikes are commonly used as defense structures for river flow channelization, protecting population and property from floods and against lateral riverbed migration. However, the aging of these structures ... [more ▼]

Dikes are commonly used as defense structures for river flow channelization, protecting population and property from floods and against lateral riverbed migration. However, the aging of these structures, combined with their increased vulnerability to extreme hydrological events may cause the dikes to breach, and subsequently to break. Furthermore, statistics show that flow overtopping is the main cause of dike failure, which emphasizes the need to understand thoroughly the process of breaching. Indeed, from a risk management perspective it is particularly important to have a detailed understanding of the mechanisms (e.g. internal erosion, overtopping erosion) underlying the formation of breaches due to overtopping and reliable information on flows passing through them. Conversely, the current knowledge of breaching mechanisms remains fragmented, especially because dike failure involves complex interactions between flows, materials of the structure, soil and foundations. The existing studies have addressed partially these interactions as the considered idealized dikes were generally homogenous, the piping erosion unaccounted for and the overtopping replicated in a dam-break like configuration. Yet, river embankments are subjected to high flow velocities parallel to the direction of the dike and to flow in the floodplain, which highly influence the shape of the breach and its evolution. The objective of the present work is to fill this gap. A laboratory experimental investigation is planned in the National Laboratory for Hydraulics and Environment (LNHE) of EDF R&D (France) and in the research group Hydraulics in Environmental and Civil Engineering (HECE) of the University of Liege (Belgium), reproducing realistic configurations of river dikes, accounting for the tangential flow in both main channel and floodplain. It enables thus the assessment of, on the one hand, the effect of the increase of the water level, and on the other hand, the influence of waves. The laboratory tests also consider the effect of a surface layer and composition of the dike core by testing different material mixtures. Geometry and composition of the idealized dikes are representative of typical field dikes, based on the similarity theory. [less ▲]

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See detailA study of composite laminates failure using an anisotropic gradient-enhanced damage mean-field homogenization model
Wu, Ling ULg; Sket, Federico; Molina-Aldareguia, Jon M et al

in Composite Structures (2015), 126

The failure of carbon fiber reinforced epoxy laminates is studied using an anisotropic gradient-enhanced continuum damage model embedded in a mean-field homogenization scheme. In each ply, a homogenized ... [more ▼]

The failure of carbon fiber reinforced epoxy laminates is studied using an anisotropic gradient-enhanced continuum damage model embedded in a mean-field homogenization scheme. In each ply, a homogenized material law is used to capture the intra-laminar failure. The anisotropy of the homogenized material model results from the homogenization method and from the reformulation of the non-local continuum damage theory to account for the material anisotropy. As a result the damage propagation direction in each ply is predicted with accuracy as compared to the experimental results, while the problems of losing uniqueness and strain localization, which occur in classical finite element simulations when strain softening of materials is involved, can be avoided. To model the delamination process, the hybrid discontinuous Galerkin/extrinsic cohesive law method is introduced at the ply interfaces. This hybrid method avoids the need to propagate topological changes in the mesh with the propagation of the delamination while it preserves the consistency and stability in the un-cracked interfaces. As a demonstration, open-hole coupons with different stacking sequences are studied numerically and experimentally. Both the intra- and inter-laminar failure patterns are shown to be well captured by the computational framework. [less ▲]

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See detailCharacterizing activity sequences using Profile Hidden Markov Models
Liu, Feng; Janssens, Davy; Cui, JianXun et al

in Expert Systems with Applications (2015), 42(13), 57055722

In literature, activity sequences, generated from activity-travel diaries, have been analyzed and classified into clusters based on the composition and ordering of the activities using Sequence Alignment ... [more ▼]

In literature, activity sequences, generated from activity-travel diaries, have been analyzed and classified into clusters based on the composition and ordering of the activities using Sequence Alignment Methods (SAM). However, using these methods, only the frequent activities in each cluster are extracted and qualitatively described; the infrequent activities and their related travel episodes are disregarded. Thus, to quantify the occurrence probabilities of all the daily activities as well as their sequential orders, we develop a novel process to build multiple alignments of the sequences and subsequently derive profile Hidden Markov Models (pHMMs). This process consists of 4 major steps. First, activity sequences are clustered based on a pre-defined scheme. The frequent activities along with their sequential orders are then identified in each cluster, and they are subsequently used as a template to guide the construction of a multiple alignment of the cluster of sequences. Finally, a pHMM is employed to convert the multiple alignment into a position-specific scoring system, representing the probability of each frequent activity at each important position of the alignment as well as the probabilities of both insertion and deletion of infrequent activities. By applying the derived pHMMs to a set of activity-travel diaries collected in Belgium as well as a group of mobile phone call location data recorded in Switzerland, the potential and effectiveness of the models in capturing the sequential features of each cluster and distinguishing them from those of other clusters, are demonstrated. The proposed method can also be utilized to improve activity-based transportation model validation and travel survey designs. Furthermore, it offers a wide application in characterizing a group of any related sequences, particularly sequences varying in length and with a high frequency of short sequences that are typically present in human behavior. [less ▲]

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See detailSpeed limit to the Abrikosov lattice in mesoscopic superconductors
Grimaldi, Gaia; Leo, Antonio; Sabatino, P. et al

in Physical Review. B : Condensed Matter (2015), 92

We study the instability of the superconducting state in a mesoscopic geometry for the low pinning material Mo3Ge characterized by a large Ginzburg-Landau parameter. We observe that in the current driven ... [more ▼]

We study the instability of the superconducting state in a mesoscopic geometry for the low pinning material Mo3Ge characterized by a large Ginzburg-Landau parameter. We observe that in the current driven switching to the normal state from a nonlinear region of the Abrikosov flux flow, the mean critical vortex velocity reaches a limiting maximum velocity as a function of the applied magnetic fi eld. Based on time dependent Ginzburg-Landau simulations we argue that the observed behavior is owed to the high velocity vortex dynamics confi ned on a mesoscopic scale. We build up a general phase diagram which includes all possible dynamic confi gurations of Abrikosov lattice in a mesoscopic superconductor. [less ▲]

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See detailSedimentological and geochemical evidence to detect arid periods recorded in wadi deposits: a case study from northern Morocco
El Ouahabi, Meriam ULg; Bartz, Melanie; Rixhon, Gilles et al

Poster (2015, July 27)

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See detailSpatio‑temporal dynamics of β‑tubulin isotypes during the development of the sensory auditory organ in rat
Renauld, Justine ULg; Johnen, Nicolas; Thelen, Nicolas ULg et al

in Histochemistry & Cell Biology (2015)

There are different β-tubulin isoforms in microtubules of vertebrate tissues. However, their functional significance is still largely unknown. In the present study, we investigated the localization of ... [more ▼]

There are different β-tubulin isoforms in microtubules of vertebrate tissues. However, their functional significance is still largely unknown. In the present study, we investigated the localization of five β-tubulin isotypes (β1– 5) within the hearing organ during development in rat. By using confocal microscopy, we showed that with the exception of the β3-tubulin isoform that was specific to nerve fibres, all the different β-tubulin isoforms were mainly present in the supporting cells. Contrary to β1–4-tubulins, we also found that the β5-tubulin isoform appeared only at a key stage of the post-natal development in specific cell types (pillar cells and Deiters’ cells). By using transmission electron microscopy, we revealed further that this developmental stage coincided with the formation of two separate bundles of microtubules from a unique one in these supporting cells. Together, these results suggest that the β5-tubulin isoform might be involved in the generation of new microtubule bundles from a pre-existing one. [less ▲]

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See detailIdentification of VZV ORF9p potential cellular partners that could be important for the viral egress.
Lebrun, Marielle ULg; riva, laura; Rambout, Xavier ULg et al

Poster (2015, July 26)

ORF9p (homologous to HSV-1 VP22) is a VZV tegument protein essential for the viral replication. During the lytic cycle it is the mostly expressed gene. We have recently demonstrated that it is a substrate ... [more ▼]

ORF9p (homologous to HSV-1 VP22) is a VZV tegument protein essential for the viral replication. During the lytic cycle it is the mostly expressed gene. We have recently demonstrated that it is a substrate of the viral kinase ORF47p and that its ORF47p-dependent phosphorylation is important for the secondary envelopment process. We also have identified an acidic cluster (AC) within the protein that is important for its correct localization in the infected cells and for the interaction with ORF47p. The recombinant VZV expressing ORF9p-ΔAC presents an accumulation of capsids in the perinuclear space. ORF9p seems then to play an important role in several steps of the egress process. In this context, we sought to identify cellular partners of ORF9p that might be important for these functions. We performed a yeast two hybrid screen against the human ORFeome 5.1. and picked out 44 candidates among which 5 proteins playing roles in membrane organization and targeting. We currently are trying to confirm these interactions in infected cells and to assess the role of these interactions for the viral lytic cycle. [less ▲]

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See detailPrediction of the excavation damaged zone in Callovo-Oxfordian claystone using a coupled second gradient model
Collin, Frédéric ULg; Pardoen, Benoît ULg

Scientific conference (2015, July 23)

The solution currently studied in France for long-term management of radioactive waste is the repository in deep argillaceous geological media with low permeability. The drilling of underground galleries ... [more ▼]

The solution currently studied in France for long-term management of radioactive waste is the repository in deep argillaceous geological media with low permeability. The drilling of underground galleries in these clayey rocks induces damage propagation in the surrounding medium. This excavation process creates a damaged zone, in which the material properties are modified. The prediction of the fracture structure and material properties evolution within this zone is a major issue especially in the context of underground disposal. Experimental works have highlighted that the damage around galleries in Callovo-Oxfordian claystone is localized and develops mainly as extensional and shear fractures. We propose to model these shear fractures as a strain localisation process in the mode of a shear band. In order to properly represent the shear strain localisation behaviour, an enhanced model introducing a regularization method and an internal length scale is needed. Among the different regularization methods, the coupled second gradient local model is chosen. To illustrate the development of the damaged zone, a two-dimensional plane strain state hydro-mechanical modelling of a gallery excavation is performed (Lagamine code, ULg) for two orientations of the gallery in the Callovo-Oxfordian claystone. Firstly, a gallery oriented along the minor horizontal principal stress is considered. In this direction, the anisotropy of the stress state in the plane perpendicular to the gallery is the predominant factor leading to the elliptical shape of the damaged zone, with a significantly larger extent in the vertical direction. Secondly, a gallery oriented along the major horizontal principal stress is modelled. The stress state in the plane perpendicular to the gallery is quasi-isotropic and does not lead to shear strain localisation unless the material anisotropy is considered. Moreover, the modelling provides information about the fracture structure and evolution around the gallery. It exhibits a chevron fracture pattern corresponding to in situ experimental measurements of shear fractures for both considered gallery orientations. [less ▲]

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See detailImpact of phenotypic heterogeneity and metabolic specialisation on metabolic engineering strategies: case of study of E.coli as a representative microbial cell factory
Brognaux, Alison ULg; Delepierre, Anissa ULg; Pecheux, Hélène ULg et al

Conference (2015, July 21)

The goal of this research is to directly highlight the simultaneous occurrence of several phenotypes with distinct metabolic function among clonal population of E. coli., often used for recombinant ... [more ▼]

The goal of this research is to directly highlight the simultaneous occurrence of several phenotypes with distinct metabolic function among clonal population of E. coli., often used for recombinant protein and pDNA production in bioprocesses. This phenotypic heterogeneity, first due to the noise, is reinforced by environmental heterogeneities occurring at large scale during fed-batch processes. This phenotypic heterogeneity has been tracked according to GFP reporter strains (biosensors) that circulate in the bioreactor and encounter environmental heterogeneities. First, we have highlighted the simultaneous occurrence of several phenotypes with distinct metabolic functions. Indeed, a diversity of glucose uptake strategies has recently been noticed with the PtsG and MglABC transporters. Moreover, when E.coli encounters zones of glucose excess, acetate is produced through the overflow metabolism. Only the sub-population with high acs expression (acetate transporter) could consume this acetate. GFP reporter strains have thus been constructed for PtsG, MgIABC and acs genes. In addition of the stable GFP, two destabilized GFP variants for each gene have been used to obtain more instantaneous responses. The response of these biosensors have been followed by on-line flow cytometry. In the end, this experimental strategy for direct phenotyping at the single cell level will also be used to investigate the impact of metabolic engineering strategies on phenotypic heterogeneity, robustness and fitness of microbial population in industrial conditions. [less ▲]

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