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See detailKin recognition and inbreeding avoidance in a butterfly
Fischer; Karl, Isabell; Heuskin, Stéphanie ULg et al

in Ethology (2015), 121

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See detailA semiquantitative framework for gene regulatory networks: increasing the time and quantitative resolution of Boolean networks
Kerkhofs, Johan ULg; Geris, Liesbet ULg

in PLoS ONE (2015), 10(6), 0130033

Boolean models have been instrumental in predicting general features of gene networks and more recently also as explorative tools in specific biological applications. In this study we introduce a basic ... [more ▼]

Boolean models have been instrumental in predicting general features of gene networks and more recently also as explorative tools in specific biological applications. In this study we introduce a basic quantitative and a limited time resolution to a discrete (Boolean) framework. Quantitative resolution is improved through the employ of normalized variables in unison with an additive approach. Increased time resolution stems from the introduction of two distinct priority classes. Through the implementation of a previously published chondrocyte network and T helper cell network, we show that this addition of quantitative and time resolution broadens the scope of biological behaviour that can be captured by the models. Specifically, the quantitative resolution readily allows models to discern qualitative differences in dosage response to growth factors. The limited time resolution, in turn, can influence the reachability of attractors, delineating the likely long term system behaviour. Importantly, the information required for implementation of these features, such as the nature of an interaction, is typically obtainable from the literature. Nonetheless, a trade-off is always present between additional computational cost of this approach and the likelihood of extending the model’s scope. Indeed, in some cases the inclusion of these features does not yield additional insight. This framework, incorporating increased and readily available time and semi-quantitative resolution, can help in substantiating the litmus test of dynamics for gene networks, firstly by excluding unlikely dynamics and secondly by refining falsifiable predictions on qualitative behaviour. [less ▲]

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See detailImpact of Different Thermal Comfort Models on Zero Energy Residential Buildings in Hot Climate
Attia, Shady ULg; Carlucci, Salvatore

in Energy & Buildings (2015)

The selection of a thermal comfort model for establishing indoor optimal hygrothermal conditions during the hot period has a major impact on energy consumption of Net Zero Energy Buildings in hot climates ... [more ▼]

The selection of a thermal comfort model for establishing indoor optimal hygrothermal conditions during the hot period has a major impact on energy consumption of Net Zero Energy Buildings in hot climates. The objective of this paper is to compare the influence of using different thermal comfort models for zero energy buildings in hot climates. The paper compares the impact of applying Fanger’s model, Givoni’s model, the ASHRAE 55 adaptive comfort model and the EN 15251 adaptive comfort model on energy consumption and comfort performance. Using both the building performance simulation tools ZEBO and EnergyPlus for energy simulation, an existing prototype of a residential apartment module is used to evaluate energy performance and thermal comfort in two parametric series. The first one is the result of coupling natural ventilation and mechanical cooling and the second one is guided coupling natural ventilation, mechanical cooling and ceiling fans. This study shows that the percentage of energy consumption difference meeting the comfort criteria according to ISO 7730 in comparison to EN 15251, ASHRAE 55 or Givoni’s model varied up to 16%, 21% and 24.7% respectively for the presented case study. More energy savings can be expected for buildings in hot climates with greater cooling demands. [less ▲]

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See detailCharacterizing the morphology of suburban settlements: a method based on a semi-automatic classification of building clusters
de Smet, Fabian; Teller, Jacques ULg

in Landscape Research (2015)

Urban sprawl is transforming our landscapes and rural areas at a spectacular pace. Measuring the strength of the phenomenon and proposing dynamic ways to delineate suburban areas have been the object of ... [more ▼]

Urban sprawl is transforming our landscapes and rural areas at a spectacular pace. Measuring the strength of the phenomenon and proposing dynamic ways to delineate suburban areas have been the object of much debate amongst scientists. The present article takes the view that, beyond measuring and delineating suburban areas, more efforts should be directed to qualifying the morphology of built settlements within these areas. Therefore it proposes a method based on a semi-automatic classification system of building clusters, designed to describe and interpret the phenomenon from a morphological perspective. This method is based on a combination of field surveys with numerical analyses of digital land cadastre maps. The application of this classification system to the suburban area around Liege reveals that, far from developing in a complete indifference of local conditions, contemporary suburban settlements are influenced by landscape structures inherited from the past. [less ▲]

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See detailHigher Octonions
Kreusch, Marie ULg

Conference (2015, June 11)

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See detailLa diversité linguistique dans l'Empire romain au temps d'Irénée : l'Asie Mineure et la Gaule
Rochette, Bruno ULg

Conference (2015, June 11)

Originaire d’Asie Mineure, Irénée est un témoin de la situation de plurilinguisme dans l’Imperium Romanum du IIe s. apr. J.-C. Comme beaucoup de ses contemporains, il est venu à Rome, ville cosmopolite au ... [more ▼]

Originaire d’Asie Mineure, Irénée est un témoin de la situation de plurilinguisme dans l’Imperium Romanum du IIe s. apr. J.-C. Comme beaucoup de ses contemporains, il est venu à Rome, ville cosmopolite au centre de l’Empire. Plutôt que de retourner dans sa patrie natale, il a poursuivi sa route vers l’Occident pour se fixer en Gaule, à Lyon, dont il deviendra évêque. Irénée a donc connu plusieurs situations linguistiques. Il se meut d’abord au sein de l’Empire romain, où deux langues coexistent, le latin et le grec, qui atteignent, durant le IIe s., un point d’équilibre, dont témoignent certaines œuvres, comme les Nuits Attiques d’Aulu-Gelle. Ensuite, l’Asie Mineure, d’où est parti Irénée, se caractérise par une grande diversité linguistique et par une survivance des parlers locaux. Le christianisme s’est appuyé sur ces langues locales, persistantes dans les campagnes, tandis que les villes, hellénisées, restaient des foyers du paganisme. Enfin, en Gaule, la question est de savoir dans quelle mesure la langue des Gaulois a persisté et a pu être connue d’Irénée. A ce sujet, un passage de la préface de l’Adversus haereses (Οὐκ ἐπιτητήεις δὲ παρ᾿ἡμῶν, τῶν ἐν Κελτοῖς διατριβόντων καὶ περὶ βάρβαρον διάλεκτον τὸ πλεῖστον ἀσχολουμένων… « Tu n’exigeras de nous, qui vivons chez les Celtes et qui, la plupart du temps, traitons nos affaires en dialecte barbare… ») mérite d’être analysé. C’est probablement le latin qu’il faut voir dernière l’expression « dialecte barbare ». [less ▲]

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See detailRegional crop and irrigation monitoring: some examples of (new) opportunities
Wellens, Joost ULg

in Begian workshop: Space4Food (2015, June 11)

Satellite images are used since long for agricultural monitoring at different spatial scales: from continental, national to regional and even field level. Combined with agro-meteorological data and ... [more ▼]

Satellite images are used since long for agricultural monitoring at different spatial scales: from continental, national to regional and even field level. Combined with agro-meteorological data and simulation models they constitute powerful decision support tools for agriculture throughout the world. Some examples at different scales and domains are presented. In Burkina Faso, free MODIS time series of coarse resolution vegetation indices (NDVI), phenological and meteorological data are combined in a multiple regression analysis for early yield warning in the cotton industry. Using a limited amount of data, it allows a decent yield forecasting more than a month before harvest. Time series of ERS radar images are analysed to monitor water intakes on the irrigated perimeter of Tadla (Morocco). The back-scatter intensity gives a clear indication of the top soil moisture state, permitting irrigation managers a regional monitoring of the irrigation water distribution and a guidance in the water allocation pricing. Actually in Belgium, and soon to be exported elsewhere, very-high resolution imagery (SPOT-5 Take5) are used to observe crop canopy development (fAPAR, fCover) on field level. Either by curve-fitting functions or assimilating these satellite derived data in existing crop growth models, improved and spatially more detailed forecasting systems are being developed. Although mostly still in the domain of applied research, the new availability of high spatial and temporal resolution imageries such those that will provide the Sentinel satellites paves the way to a growing number of operational end users. [less ▲]

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See detailEvaluation du décret du 30 avril 2009 relatif au développement des pratiques de lecture organisé par le réseau public de la lecture et les bibliothèques publiques. Troisième rapport : première partie : Enquête Delphi, analyse du deuxième tour
Fallon, Catherine ULg; Halin, Jordan ULg; Italiano, Patrick ULg et al

Report (2015)

This report presents results of a Delphi online (Mesydel software) survey about evaluation of "décret du 30 avril 2009 relatif au développement des pratiques de lecture organisé par le réseau public de la ... [more ▼]

This report presents results of a Delphi online (Mesydel software) survey about evaluation of "décret du 30 avril 2009 relatif au développement des pratiques de lecture organisé par le réseau public de la lecture et les bibliothèques publiques" in Wallonia-Brussel Federation. This survey in two rounds questionned a hundred public libraries about the implementation of the decret. [less ▲]

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See detailCHRONIC TOXIC HEPATITIS IN BEEF CALVES DUE TO MYCOTOXINS CONTAMINATION IN MIXED FEED
Theron, Léonard ULg; Callebaut, Alfons; Bayrou, Calixte ULg et al

in Zemljic, Borut; Podpecan, Ozbalt; Zmljic-Jokhadar, Spela (Eds.) Proceedings of the XV middle European Buiatric Congress (2015, June 10)

Mycotoxins intoxination is an emerging disorder in Belgium, due to evolution of cultural practices and harvesting weather conditions. These intoxinations are difficult to diagnose for the vet practioners ... [more ▼]

Mycotoxins intoxination is an emerging disorder in Belgium, due to evolution of cultural practices and harvesting weather conditions. These intoxinations are difficult to diagnose for the vet practioners, since unspecific clinical signs, and their impact on ruminant disorder remains controversial. Although legal concentrations have been established for mycotoxins in the EU, farm forages are most of the time not tested (EU 2006/576/EC). In January 2015, a 500 calvings cross-bred Belgian blue cattle herd (BVDV free) referred a second (the first was directly sent to the rendering-plant) unexplained fatal case of jaundice on a 2 months-old calf to the Clinic for Ruminants of the University of Liège for necropsy. In 2013, a case of jaundice due to a Salmonella dublin hepatocholecystitis had previously diagnosed in this farm (Ronzoni et al., 2014), but so far preventions measures were implemented. Necropsy revealed generalized icterus, mild bilirubinuria, splenomegaly, but no precise etiology. On February a second 2 month old calf with jaundice is referred, lethargic, normothermic with a mild diarrhea, Calf shown generalized jaundice, anemia, elevation of leukocytes (neutrophils, eosinophils and monocytes), TGO, bilirubinemia, total biliary acids and Globulins (alpha2). He had also diminished erythrocytes and albuminemia. Copraemia, leptospirosis serology, leademia, hemoculture and pancreatic enzymes were within normal ranges, ruling out classic causes of jaundice in calf. Abdomen ultrasonography revealed a mild hyperechogenicity of the liver but no gall bladder modifications. Symptomatic treatment was based on symptoms, with fluidotherapy and choleretics. A third calf was referred three days after in a worst clinical condition, with also a severely modified liver enzymes, but no anemia. Three days after, this calf died and a necropsy revealed petechiae and hemorrhages in the abomasum, congestive mucosae in the distal bowel, white depot in the kidney medulla, modified urine and splenomegaly. Bile bacteriology and leptospirosis PCR was negative and liver histopathology revealed a severe histopathological liver degeneration associated with a disruption of the parenchyma and marked hyperplasia of the bile ducts compatible with chronic metabolic disorder. Meanwhile, the anemic calf recovered from anemia without any treatment after 4 days and was discharged from the Clinic for Ruminants. Considering the weird clinical patterns of these jaundice cases, and the fact that only calves from 2 to 3 months were affected, a nutritional origin as etiology was suspected. To test it, eight clinically healthy two to three months-old calves, of two different pens were sampled. TGO, GLDH, GGT or biliary acids were either modified and the values tended to increase with the age of the calves. The water was analyzed for classic toxics, and cultured for total germ content and everything were within recommended values. The calves fed with a milk replacer (30 % milk powder), and a commercial calf starter until one month of age. Then, they were given a mixed feed (containing cereal mix, cocoa, beet pulp, soja, maize), made at the farm from primary product/byproducts bought from different sources. The mix was tested for mycotoxins presence and ranged from 0.8 to 1.5 ppm of Desoxynivalenone (DON), and 115-215 ppb of Zearalenone (ZEA). The principal source of DON was maize (3.1 to 6.2 ppm), as for ZEA (0.3-0.6 ppm), but several compounds contained small dose of DON (0.2-0.7 ppm) for Barley feed, Tanned soja. Cacao contained 2.7 to 5.9 ppb of Ochratoxine (OTA). Nutritionnal recommendations were immediately given with a change in the source of maize and an addition of clay and yeast at 40g/calf/day and hay. Since, any other hypothetic origin to this progressive hepatic intoxination was demostrated, and that the doses founded, even if barely legal in the mix, are not accounted for toxic in the EU regulation, we believe that the calves were chronically exposed to these toxins. However, some mycotoxins experts still claim that various clinical signs would be observed in ruminants, if the rumen is partially defaunated, like in our case with the lake of forage. We propose that monitoring of subclinical liver health could be a key to screen DON effects. [less ▲]

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See detailLes genres médiatiques de l’anticipation : des usages comiques du futur
Stienon, Valérie ULg

Conference (2015, June 10)

La petite presse multiplie volontiers les usages comiques de la prédiction, tantôt en empruntant ses effets à l’almanach, tantôt en traitant au second degré les marronniers trop familiers, tantôt encore ... [more ▼]

La petite presse multiplie volontiers les usages comiques de la prédiction, tantôt en empruntant ses effets à l’almanach, tantôt en traitant au second degré les marronniers trop familiers, tantôt encore en infléchissant vers la prospective le principe de la revue de fin d’année. Ainsi, il est fréquent que les petits journaux satiriques feignent d’imaginer les événements à venir sous la forme de « prédictions pour l’année » et de « coups d’œil prophétiques ». Après certaines pages du Charivari dans les années 1830 et 1840, l’humour d’un Albert Robida dans la Caricature a contribué à populariser ces procédés dans les années 1880. Si de telles éphémérides parodiques ne bénéficient pas de la stabilité d’une rubrique spécifique, elles sont toutefois appelées, au siècle suivant, à prendre l’ampleur de numéros complets qui témoignent d’une postérité intéressante (Illustration, Lectures pour tous, VU, Sciences et voyages) et d’une créativité iconotextuelle qui peut aller jusqu’au faux reportage photographique d’anticipation. Aussi fréquentes que polymorphes et éparpillées, ces prédictions comiques composent une microforme médiatique inhérente à la modernité de la petite presse, et ce par deux aspects au moins. D’une part, leur discursivité porte sur des données socioculturelles présentées comme remarquables et novatrices, censées incarner la quintessence de leur époque tout entière tendue vers l’avenir, ce qu’appuie encore l’intertextualité avec le merveilleux scientifique issu des pages de vulgarisation scientifique. D’autre part, leur poétique affiche une temporalité méta-médiatique renvoyant aux fonctions rituelles et référentielles du périodique, occasion de déployer une fiction publicitaire qui fait double office de support fantasmatique de projection et de vecteur autopromotionnel du journal. Cette communication a proposé une première recension et des éléments de poétique historique pour mieux cerner dans sa variété un sous-genre médiatique encore peu considéré. On a examiné, outre les procédés privilégiés (numéro circonstanciel d’étrennes, éphéméride parodique, revue de fin d’année détournée, billet d’humeur, recension culturelle, déclinaison médiatique de la féérie, etc.) et les transformations discursives que leur applique le second degré de la petite presse, les réalités socioculturelles sur lesquelles porte principalement l’anticipation (mode, progrès techniques, avancées sociales, produits de l’industrie), afin de définir quels objets médiatiques sont ainsi construits en discours et en représentations par le journal dans un commentaire qui veut cerner les promesses de modernité dans l’actualité. [less ▲]

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See detailSeagrass macrophytodetritus: a copepod hub - Species diversity, dynamics and trophic ecology of the meiofauna community in Posidonia oceanica leaf litter accumulations
Mascart, Thibaud ULg

Doctoral thesis (2015)

Macrophytodetritus is a heterogeneous mixture of detrital material that accumulates on submerged unvegetated sand patches amid vast Mediterranean Posidonia oceanica seagrass meadows. Several vagile ... [more ▼]

Macrophytodetritus is a heterogeneous mixture of detrital material that accumulates on submerged unvegetated sand patches amid vast Mediterranean Posidonia oceanica seagrass meadows. Several vagile invertebrates are present in substantial biomass and biodiversity. Among these invertebrates, meiofauna (fauna between 38µm and 1mm) is ubiquitous and seems to play a key-feature in this dynamic and patchy system. Coastal ecosystems are under the direct effect of anthropogenic disturbance and degradation. Extra research is crucially needed to understand better the dynamics of coastal vegetation, in order to have a more successful restauration of these regressing ecosystems. In this context, the main goal of this PhD research was triple: (1) characterising in situ the physico-chemistry and the composition of the macrophytodetritus accumulations in the Calvi Bay, Corsica, (2) identifying the diversity of the associated meiofauna communities, especially harpacticoid copepods together with unravelling the origin of the present copepods and (3) characterizing the trophic ecology of the copepod communities in the macrophytodetritus at the specific and eco-morphological level. This research showed that macrophytodetritus biomass is composed on average for 75% of dead P. oceanica seagrass leaves shed after senescence. Attached to the surface of the seagrass leaves numerous micro- and macroepiphytes are present, representing on average 10% of the total biomass. The remaining part is mainly constituted of drift material, like detached P. oceanica shoots and epilithic macroalgae. A seasonal pattern is observed regarding the amount of accumulated material and the physico-chemical composition inside the accumulation. Wind-induced hydrodynamics is the responsible driver behind the variability of the macrophytodetritus and consequently it has a major impact on the faunal communities already present in a macrophytodetritus accumulation. Previous studies showed that the presence of macrofaunal invertebrates (> 1 mm) in high amounts contributes to the degradation of the detritus. Similarly, this study proves the ubiquitous presence of meiofauna in macrophytodetritus. Depending on the season, densities from 20.10³ to 160.10³ meiofaunal organisms per square metre of accumulation were recorded. Copepods were the most abundant taxon (> 50%) of which 87% belonged to the order Harpacticoida. Nematodes were the second most abundant taxon, representing on average 18% of the total meiofauna densities. A total of 61 copepod species were found in Calvi Bay macrophytodetritus accumulations and adjacent habitats (bare sand, seagrass and water column), wherefrom 85% were shared amongst these habitats, underlining the high colonization capabilities of copepods. Active colonization occurred within 24h through species-specific dispersal pathways. Certain species were more avid to colonize, resulting in a colonizer-competitor trade-off among the copepod community. Eco-morphological characteristics seemed to be responsible for the dispersal potential. However, the variety of the composition of the copepod community suggested that other factors also contributed to the attractiveness of the structurally complex macrophytodetritus habitat. The isotopic niches of four abundant copepod species, representing four different eco-morphological groups were identified: Ectinosoma dentatum (mesopsammic-type), Diosaccus tenuiremis (phytal-type), Tisbe furcata (epibenthic-type) and Clausocalanus arcuicornis (water-column-type). Based on stable isotope analysis, fatty acid profiling and Bayesian mixing model, results suggested an interspecific diversity which would indicate a species-specific resource partitioning. C. arcuicornis mainly fed on suspended organic matter, while D. tenuiremis thrived mainly on epiphytes (mostly diatoms). E. dentatum was dependent on the seasonal availability of food sources, while T. furcata fed on a heterogeneous mixture of sources. Presumably none of the species directly assimilated dead seagrass leaf litter. Overall, by combining in situ sampling, novel mesocosm experiment, biomarkers and mixing models, this study displayed the carrying capacity of macrophytodetritus to support a large amount of meiofauna and a wide diversity of copepod species. The morphological differences among copepod species seem to allow specialization towards habitat preferences, (physical habitat preferences and colonization potential) and towards resource preferences (food partitioning). Macrophytodetritus seems thus to be a suitable home, or a temporary hub for a diverse copepod community. Finally, this dynamic and patchy habitat, prone to swift changes and situated at the crossing of different ecosystems, plays a major role in coastal ecology. [less ▲]

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See detailLes chantiers d’églises rurales dans l’ancien diocèse de Liège à la fin du Moyen Âge et au début des Temps modernes
Joly, Emmanuel ULg

Conference given outside the academic context (2015)

Dans l’histoire de l’architecture, il est incontestable de dire que l’architecture des édifices religieux est la plus étudiée, la plus commentée. Il est néanmoins un type d’édifice qui occupe moins que ... [more ▼]

Dans l’histoire de l’architecture, il est incontestable de dire que l’architecture des édifices religieux est la plus étudiée, la plus commentée. Il est néanmoins un type d’édifice qui occupe moins que les autres l’esprit des chercheurs de cette discipline : l’église rurale. Ces édifices couvrent pourtant l’ensemble de l’Europe et constituent chacun d’eux le centre, le point d’ancrage d’une communauté rurale. Centre d’une circonscription religieuse, lieu de réunion, de dévotion, symbole visible et permanent des divers acteurs du monde rural, l’église rurale est essentielle pour comprendre le fonctionnement des communautés rurales. Mal documentés, parfois d’aspect ingrat, ces édifices n’invitent cependant pas l’amoureux des formes artistiques à en faire son objet d’étude de prédilection. Si son objectif est en effet de fonder les bases de grands courants artistiques, l’église rurale n’est qu’en de rares cas un objet idéal. Mais il faut dépasser cette attitude et réévaluer l'architecture des églises rurales à travers les données que nous offrent à la fois l'histoire institutionnelle de ces édifices, la documentation et la compréhension des processus de construction de ces églises, et l'identification des personnes impliquées dans ces chantiers. La communication propose de mettre en place cette approche en se basant sur des exemples issus de l'ancien diocèse de Liège. [less ▲]

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See detailStudying the great potential of cultivable bacteria associated with the brown alga Ascophyllum nodosum
Martin, Marjolaine ULg; Martin, Renée ULg; Barbeyron, Tristan et al

Poster (2015, June 09)

Bacteria associated with algae differ markedly from those living freely in seawater and represent great potential for the production of diverse bioactive compounds as they interact in multiple complex ... [more ▼]

Bacteria associated with algae differ markedly from those living freely in seawater and represent great potential for the production of diverse bioactive compounds as they interact in multiple complex ways with their host. Here we identified new bacterial species, and their polysaccharolytic activities, associated with the brown alga Ascophyllum nodosum. To isolate cultivable microorganisms, algal thalli of Ascophyllum nodosum were swabbed with sterile cotton tips and marine agar plates were inoculated. Three-hundred isolated bacteria were screened for agarase, kappa- or iota-carrageenase activities on specific marine media. Thirty-two bacteria with polysaccharolytic activities were isolated and a part of their 16S rDNA (8F-1492R) were amplified and sequenced. Twenty-seven were classified as Flavobacteriia and five as Gammaproteobacteria. Putative new strains and species of Zobellia, Maribacter, Cellulophaga, Shewanella, Glaciecola, Pseudoalteromonas and Colwellia were identified by phylogenetic analysis. Genomics libraries with their DNA were constructed in Escherichia coli and Bacillus subtilis and are currently screened for diverse enzymatic activities (agarases, iota-and kappa-carrageenases, cellulases, beta-glucosidases, sulfatases and amylases). In an era where high throughput sequencing is mostly used to study bacterial communities, cultivation methods are underestimated. Here, we revealed that only ten percent of the cultivable bacteria on this brown alga could degrade algal polysaccharides, which lead to asking us; who and what are the 90 other percents doing there? Furthermore, by this cultivation method we could also identify putative new bacterial strains/species, which are screened for polysaccharidases. Novel glycoside hydrolases from unknown marine bacteria represent great biotechnological potential as they should have original industrial properties. [less ▲]

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