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See detailDiversity dynamics of non-lycopsid lycophytes
Cascales - Miñana, Borja ULg; Meyer-Berthaud, Brigitte

in Cascales - Miñana, Borja; Villanueva-Amadoz, Uxue; Diez, José B. (Eds.) Proceedings of the II Agora Paleobotanica Meeting (Abstract book) (2013, July)

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See detailDiversity dynamics of Zosterophyllopsida
Cascales - Miñana, Borja ULg; Meyer-Berthaud, Brigitte

in Lethaia (2014), 47(2), 205-215

The Zosterophyllopsida were major contributors to the diversification of early land plants. We present the first detailed analysis of the diversity dynamics of these plants from an updated database of all ... [more ▼]

The Zosterophyllopsida were major contributors to the diversification of early land plants. We present the first detailed analysis of the diversity dynamics of these plants from an updated database of all currently recognized zosterophyllopsid species. A set of quantitative methods classically used in palaeodiversity studies was applied to two data sets. The first one, 'Zosterophyllopsida sensu stricto', corresponds to the clade identified by Hao & Xue (The Early Devonian Posongchong Flora of Yunnan. (2013), Science Press). In the second, called 'Zosterophyllopsida sensu lato', barinophytalean-type plants and taxa for which zosterophyllopsid affinities are suspected are added. The number of localities is used to explore sampling bias. Results show that sampling effect is minimal for the Early Devonian. For this time interval, both data sets record consistent patterns of changes suggesting that, whatever their affinities, all taxa included in the Zosterophyllopsida sensu lato show similar evolutionary trends. The diversity dynamics of zosterophyllopsids are characterized by a radiation during the Lochkovian, maximal values in the Pragian and a decline starting in the Emsian. The proportion of zosterophyllalean taxa with terminal sporangia is high until the Late Lochkovian when gosslingialean taxa without terminal sporangia evolved. During the Middle and Late Devonian, when diversity patterns are strongly affected by sampling, zosterophyllopsid diversity is low and characterized by a high proportion of barinophytacean and gosslingialean taxa, the latter becoming extinct in the Early Frasnian. © 2013 The Lethaia Foundation. [less ▲]

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See detailDiversity dynamics of Zosterophyllopsida (Lycophyta, Middle Paleozoic)
Cascales - Miñana, Borja ULg; Meyer-Berthaud, Brigitte

Conference (2013, September)

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See detailDiversity in the City
Piquard, B.; Martiniello, Marco ULg

Book published by University of Deusto, Humanitatianet (2002)

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See detailDiversity in the City
Martiniello, Marco ULg; Piquard, Bernadette

Book published by University of Deusto (2002)

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See detailDiversity in the sound production mechanism in Ophidiiformes
Parmentier, Eric ULg; Mann, David; Kever, Loïc ULg et al

Conference (2010)

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Peer Reviewed
See detailDiversity Management in Belgium
Cornet, Annie ULg; Zanoni

Conference (2010)

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See detailDiversity management status in morocco. an exploratory stydu
El Abboubi, Manal ULg; El Kandoussi, Fatima

Conference (2009, July 16)

The purpose of this article is to explore diversity management specificities in arab countries, especially in Morocco (North Africa). We analyse organisational initiatives, managers’ perception and the ... [more ▼]

The purpose of this article is to explore diversity management specificities in arab countries, especially in Morocco (North Africa). We analyse organisational initiatives, managers’ perception and the way they mainstream diversity tools in their management. The Moroccan industry is based on two major sectors: agriculture food and textile. Those two activities represent more than 50% of the PIB, 70% of the national employment and 75% of exportations. We focus our study on those two sectors which are a pillar of the morrocan economy. Our sample consist of 30 questionnaire sent to companies that have more than 50 employees. We received 16 answers. We questioned CEOs, managers, middle managers and employees. The main contribution of the research is that moroccan leaders are aware of their responsibilities to implement and carry out diversity projects. The main topics mentioned concerns equality and gender. However, they have no skills or power to ensure that responsibilities fully. Diversity management is not included in the strategy. It remains a minor task operated mainly by the human resource department. Morrocan managers need more specific trainings and a global governmental policy to guide their actions. Employees are not well informed about their rights. Moreover, Morocco will open a free exchange zone in 2010. This is an opportunity for many international companies to invest in the country. Most of them are from Europe and USA. They are well informed about diversity management, especially gender issues. This represents a threat for Moroccan companies who feel the urgency to develop a national framework for diversity management. Our research is still under study. We are collecting more data and we aim to integrate some extra stakeholders in the sample. Mainly the government and the local communities. The fact that we interviewed only managers gives us a limited view of the diversity management status in Morocco. [less ▲]

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See detailDiversity of Bacterial Communities in a Profile of a Winter Wheat Field: Known and Unknown Members
Stroobants, Aurore ULg; Degrune, Florine ULg; Olivier, Claire et al

in Microbial Ecology (2014)

In soils, bacteria are very abundant and diverse. They are involved in various agro-ecosystem processes such as the nitrogen cycle, organic matter degradation, and soil formation. Yet, little is known ... [more ▼]

In soils, bacteria are very abundant and diverse. They are involved in various agro-ecosystem processes such as the nitrogen cycle, organic matter degradation, and soil formation. Yet, little is known about the distribution and composition of bacterial communities through the soil profile, particularly in agricultural soils, as most studies have focused only on topsoils or forest and grassland soils. In the present work, we have used bar-coded pyrosequencing analysis of the V3 region of the 16S rRNA gene to analyze bacterial diversity in a profile (depths 10, 25, and 45 cm) of a well-characterized field of winter wheat. Taxonomic assignment was carried out with the Ribosomal Database Project (RDP) Classifier program with three bootstrap scores: a main run at 0.80, a confirmation run at 0.99, and a run at 0 to gain information on the unknown bacteria. Our results show that biomass and bacterial quantity and diversity decreased greatly with depth. Depth also had an impact, in terms of relative sequence abundance, on 81 % of the most represented taxonomic ranks, notably the ranks Proteobacteria, Bacteroidetes, Actinobacteridae, and Acidobacteria. Bacterial community composition differed more strongly between the topsoil (10 and 25 cm) and subsoil (45 cm) than between levels in the topsoil, mainly because of shifts in the carbon, nitrogen, and potassium contents. The subsoil also contained more unknown bacteria, 53.96 % on the average, than did the topsoil, with 42.06 % at 10 cm and 45.59 % at 25 cm. Most of these unknown bacteria seem to belong to Deltaproteobacteria, Actinobacteria, Rhizobiales, and Acidobacteria. [less ▲]

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See detailThe diversity of Clostridial hydrogenases and biohydrogen production
Calusinska, Magdalena ULg; Savichtcheva, Olga; Masset, Julien ULg et al

Poster (2009, June 18)

Molecular hydrogen is a key intermediate in metabolomic interactions of a wide range of microorganisms. Hydrogen is also regarded as a key component in future energy systems as it is a sustainable, clean ... [more ▼]

Molecular hydrogen is a key intermediate in metabolomic interactions of a wide range of microorganisms. Hydrogen is also regarded as a key component in future energy systems as it is a sustainable, clean, and transportable energy carrier. Some microorganisms can produce hydrogen during a reversible reduction of protons to dihydrogen, a reaction which is catalyzed by hydrogenases [1]. Hydrogenases belong to an iron – sulphur protein family, that contains active sites consisting of inorganic sulfide and iron atoms bound to the polypeptide chain. On the basis of their bimetallocenter composition hydrogenases are divided into three main groups, phylogenetically not related: [NiFe] hydrogenases, [Fe] only hydrogenases and ‘metal – free hydrogenases’ which were described in methanogenic Archaea only. [NiFe] hydrogenases, composed of at least two subunits are well characterized and widely distributed between Archaea and Bacteria but only a few representatives of Clostridium possess this type of enzyme. On the other hand, [Fe] only hydrogenases, being usually monomeric enzymes and restricted to Bacteria and a few eukaryotic species are far less described. These proteins, being omnipresent catalysts of many biological reactions, are especially abundant in Clostridia. The physiological function of Clostridial [Fe] only hydrogenases is to dispose under the form of hydrogen, of the excess of reducing power generated during the fermentation of carbohydrates. The unusual diversity of forms of [Fe] only hydrogenases within Clostridia seems to support the central role of this enzyme in cell metabolism and to facilitate the quick adaptation of the host to changing environmental conditions. Moreover, the presence of multiple putative operons encoding for multisubunit [Fe] only hydrogenases in the genomes of sequenced Clostridium spp. is highlighting the need to study the new, not yet described function of these ostensibly simple proteins. In this project, we have focused our effort on the molecular characterization of key enzymes involved in the process of biohydrogen production with a special interest in Clostridium species. By applying molecular techniques on samples from different kinds of bioreactors, we want to select highly productive species in terms of hydrogen generation. We also believe that gene expression profiling will provide new data on the possible function and activity of different hydrogenases involved in the process. The better understanding of hydrogen metabolism is essential for its sustainable production. [less ▲]

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See detailThe diversity of clostridial hydrogenases revealed by genome sequencing projects
Calusinska, Magdalena ULg; Wilmotte, Annick ULg; Joris, Bernard ULg

Poster (2009, December 15)

Molecular hydrogen is a key intermediate in metabolomic interactions of a wide range of microorganisms. Hydrogen is also regarded as a key component in future energy systems as it is a sustainable, clean ... [more ▼]

Molecular hydrogen is a key intermediate in metabolomic interactions of a wide range of microorganisms. Hydrogen is also regarded as a key component in future energy systems as it is a sustainable, clean, and transportable energy carrier. Some microorganisms can produce hydrogen during a reversible reduction of protons to dihydrogen, a reaction which is catalyzed by the enzyme hydrogenases. On the basis of their bimetallocenter composition, hydrogenases are divided into three main groups, phylogenetically not related: [NiFe] hydrogenases, [Fe] only hydrogenases and FeS cluster free hydrogenases. The latter were described in methanogenic Archaea only. [NiFe] hydrogenases, composed of at least two subunits are well characterized and widely distributed between Archaea and Bacteria. However, only a few representatives of Clostridium sp. possess this type of enzyme. On the other hand, much less is known about the [Fe] only hydrogenases, that are usually monomeric enzymes and restricted to Bacteria and a few eukaryotic species. Genome sequencing projects gave a completely new insight into the diversity of forms of putative [Fe] only hydrogenases within the genus Clostridium. With the use of bioinformatic tools, we have described the unusual modularity of forms of these enzymes, from monomeric to tetrameric with a different number of accessory domains reacting with diverse redox partners. This fact seems to support the central role of hydrogenases in cell metabolism and quick adaptation of the host to changing environmental conditions. Moreover, the presence of multiple putative operons encoding for multisubunit [FeFe] hydrogenases is highlighting the fact that hydrogen metabolism is very complex in the Clostridium genus. [less ▲]

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See detailDiversity of Clostridium difficile isolates from humans and animals
Rodriguez Diaz, Cristina ULg; Taminiau, Bernard ULg; Korsak Koulagenko, Nicolas ULg et al

Scientific conference (2014, October 17)

Clostridium difficile is an important cause of infectious diarrhea in hospitals. The major risk factors for the development of nosocomial C. difficile associated disease include antibiotic therapy and ... [more ▼]

Clostridium difficile is an important cause of infectious diarrhea in hospitals. The major risk factors for the development of nosocomial C. difficile associated disease include antibiotic therapy and increasing age. In animals, as pigs, calves and horses, C. difficile also seems to be an important cause of enteric disease. The main objective of this study was to characterize and compare animal and human C. difficile strains with respect to the PCR-ribotype and the antibiotic resistance. Multilocus sequence typing (MLST) and multiple-Locus Variable number tandem repeat analysis (MLVA) were performed in order to study clonal relationships of the isolates. Human C. difficile isolates were obtained from care home residents and hospitalized patients. Animal isolates were collected from stool samples and carcasses of pigs and cattle at slaughter. An identification of the strains was performed by PCR-ribotyping. Further characterization was performed by antibiotic resistance, MLST and MLVA analysis. A neighbourd-joining phylogenetic three was constructed in order to determine the correlation between human and food isolates. A great variety of PCR ribotypes was found among the animal isolates, including PCR ribotypes 078 and 014. The most prevalent PCR-ribotypes in the nursing home were PCR-ribotypes 027 and 020. A high resistance to moxifloxacin, erythromycin, gentamicin and clindamycin was detected for some of the strains. Phylogenetic analysis showed that human and animal isolates with the same PCR-ribotype cluster in the same lineage, suggesting a potential risk of interspecies transmission. [less ▲]

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See detailDiversity of cucurbit species cultivated in Côte d'Ivoire for Edible Seeds
Zoro Bi, I.; Koffi; Dje, Y. et al

in Cucurbit Genetics Cooperative, Report 2005 (2005), (28-29), 84-90

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See detailDiversity of culturable bacteria including Pantoea in wild mosquito Aedes albopictus
Claire Valiente, Claire; Tran, Florence Hélène; Raharimalala, Fara Nantenaina ULg et al

in BMC Microbiology (2013), 13

Background: The microbiota has been shown to play an important role in the biology of insects. In recent decades, significant efforts have been made to better understand the diversity of symbiotic ... [more ▼]

Background: The microbiota has been shown to play an important role in the biology of insects. In recent decades, significant efforts have been made to better understand the diversity of symbiotic bacteria associated with mosquitoes and assess their influence on pathogen transmission. Here, we report the bacterial composition found in field-caught Aedes albopictus populations by using culture-dependent methods. Results: A total of 104 mosquito imagos (56 males and 48 females) were caught from four contrasting biotopes of Madagascar and their bacterial contents were screened by plating whole body homogenates on three different culture media. From 281 bacterial colony types obtained, amplified ribosomal DNA restriction analysis (ARDRA) showed they had 40 distinct ribotypes. Sequencing and BLAST analysis of the 16S rDNA genes responsible for each representative profile made it possible to identify 27 genera distributed in three major phyla. In female mosquitoes, bacterial isolates were mostly Proteobacteria (51.3%) followed by Firmicutes (30.3%) and Actinobacteria (18.4%). Conversely, Actinobacteria was the most abundant phylum in male mosquitoes (48%) followed by Proteobacteria (30.6%) and Firmicutes (20.4%). The relative abundance and composition of isolates also varied between sampling sites, ranging from 3 distinct families in Ankazobe to 8 in Tsimbazaza Park, and Toamasina and Ambohidratrimo. Pantoea was the most common genus in both females and males from all sampling sites, except for Ambohidratrimo. No differences in genome size were found between Pantoea isolates from mosquitoes and reference strains in pulse field gel electrophoresis. However, according to the numbers and sizes of plasmids, mosquito isolates clustered into three different groups with other strains isolated from insects but distinct from isolates from the environment. Conclusions: The recent upsurge in research into the functional role of the insect microbiota prompts the interest to better explore the role some bacteria detected here may have in the mosquito biology. Future studies of culturable bacteria might decipher whether they have a biological role in the invasiveness of Ae. albopictus. As a possible candidate for paratransgenesis, the predominant genus Pantoea will be characterized to better understand its genetic contents and any possible influence it may have on vector competence of Ae. albopictus. [less ▲]

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See detailDiversity of Ecosystems and Coastal Ocean CO2 Fluxes
Borges, Alberto ULg

Conference (2005)

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See detailDiversity of forensic rove beetles (Coleoptera, Staphylinidae) associated with decaying pig carcass in a forest biotope
Dekeirsschieter, Jessica ULg; Frederickx, Christine ULg; Verheggen, François ULg et al

in Journal of Forensic Sciences (2013)

Most forensic studies are focused on Diptera pattern colonization while neglecting Coleoptera succession. So far, little information is available on the postmortem colonization by beetles and the ... [more ▼]

Most forensic studies are focused on Diptera pattern colonization while neglecting Coleoptera succession. So far, little information is available on the postmortem colonization by beetles and the decomposition process they initiate under temperate biogeoclimatic countries. These beetles have however been referred to as being part of the entomofaunal colonization of a dead body. Forensic entomologists need increased databases detailing the distribution, ecology and phenology of necrophagous insects, including staphylinids (Coleoptera, Staphylinidae). While pig carcasses are commonly used in forensic entomology studies to surrogate human decomposition and to investigate the entomofaunal succession, very few works have been conducted in Europe on large carcasses. Our work reports the monitoring of the presence of adult rove beetles (Coleoptera, Staphylinidae) on decaying pig carcasses in a forest biotope during four seasons (spring, summer, fall and winter). A total of 23 genera comprising 60 species of rove beetles were collected from pig carcasses. [less ▲]

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See detailDiversity of germination strategies and seed dormancy in herbaceous species of campo rupestre grasslands
Le Stradic, Soizig ULg; Silveira, Fernando A. O.; Buisson, Elise et al

in Austral Ecology (2015), 40(5), 537-546

The effects of fire on the vegetation vary across continents. However, in Neotropical fire-prone grasslands, the relationship between fire and seed germination is still poorly understood, while their ... [more ▼]

The effects of fire on the vegetation vary across continents. However, in Neotropical fire-prone grasslands, the relationship between fire and seed germination is still poorly understood, while their regeneration, especially after strong anthropogenic disturbance, is challenging for their conservation. In the present study, we assessed diversity of germination strategies in 15 dominant herbaceous species from Neotropical altitudinal grasslands (locally known as campos rupestres). We exposed seeds to several fire-related treatments. We also compared germination between regularly and post-fire fruiting species. Finally, we investigated the diversity of dormancy classes aiming at better understanding the biogeography and phylogeny of seed dormancy. Germination strategies varied among families. Velloziaceae and Xyridaceae produced non-dormant, fast-germinating seeds. Cyperaceae and Poaceae showed an extremely low or null germination due to a high proportion of unviable or embryo-less seeds. The seeds of campo rupestre grasslands are fire resistant, but there is no evidence that fire triggers germination in this fire-prone ecosystem. Although heat and charred wood did not promote germination, smoke enhanced germination in one grass species and decreased the mean germination time and improved synchrony in Xyridaceae and Velloziaceae. Fire had a positive effect on post-fire regeneration by stimulating fruit set in some Cyperaceae and Poaceae species. These species produced faster germinating seeds with higher germination percentage and synchrony compared to regularly fruiting Cyperaceae and Poaceae species. This strategy of dispersion and regeneration seems to be an alternative to the production of seeds with germination triggered by fire. Physiological dormancy is reported for the first time in several clades of Neotropical plants. Our data help advance the knowledge on the role of fire in the regeneration of Neotropical grasslands. © 2015 Ecological Society of Australia. [less ▲]

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See detailDiversity of governance in European cities: towards an indicators-based analysis of good governance?
Breuer, Christophe ULg

Conference (2011)

Nowadays, the attractiveness of cities and metropolitan areas seems to be a central challenge for competitiveness, territorial cohesion and economic development on a European and regional scale (European ... [more ▼]

Nowadays, the attractiveness of cities and metropolitan areas seems to be a central challenge for competitiveness, territorial cohesion and economic development on a European and regional scale (European Commission, 2009). The interest carried by actors of territorial development on large urban areas and metropolises is essentially explained by their relative weight in regional economies and their role of catalyst for sustainable development. In the absence of competitive cities, many experts estimate that territories cannot completely develop their socio-economic potential. This report is one of the bases of the strategy for city polycentric systems recommended by the development scheme of the European Community space (SDEC - European Commission, 1999), renewed in many strategic European “papers”. This strategy rose during the last decades whereas the dynamic affecting urban areas was strongly modified by the increase in mobility through two scales. On one hand, the intra-urban scale refers to processes of exurbanisation, urban sprawl, as well as functional and institutional fragmentation. On the other hand, the interurban scale has shown phenomenons of metropolisation and an increase in exchanges between cities. Cities changes, networks and urban hierarchies which result from this dynamic, apply new tensions on urban areas - in particular the biggest of them. Theses tensions have to be answered to avoid any loss of competitiveness. In this context, the ‘good governance’ of urban areas is often presented like an essential factor for their development. It is necessary to understand through the notion of “governance” the definition from Le Galès (1995) that is “a process of coordination of actors, social groups, and institutions to achieve clear goals discussed and defined collectively in split up environments”. Thus, cities governance (but also networks of cities) acts on the whole “city system” through all its complexity. The predominant role of governance generally takes the shape of a postulate, as well in the scientific world as in the active and political discourse. Nevertheless, the relation between the governance of urban areas/ cities/ metropolises and their absolute versus relative evolution in networks is not a subject for abundant theoretical studies nor empirical validations. Considering its rasing importance within territorial development policies, it must be clarified allowing a new and quantified highlight on strategies of most important urban areas. While general objectives of urban “good governance” are clearly identified in many documents, concrete impacts of governance on the urban development are ambiguous and unclear. In addition, the definition of “good governance” is regularly paradigm-oriented and often dedicated to the third world or emergent countries (as heritage of many international organisations politic which promotes development and trade efficiency). Furthermore, it appears that former studies on European and North-American cities are relatively factual and suggest a poor typology of the governance in urban areas. They are consequently not very useful for the development of a conceptual model that associates competitiveness of cities and urban governance. Consequently, our research aims at considering the impacts of governance on cities and metropolises through a set of “keys to understanding” theoretically based. We lead our work to a critical analysis of literature in order to highlight expected interactions between governance and urban territories. The construction of a conceptual scheme of interactions will allow the identification of useful indicators of governance. The identification of a set of indicators to measure governance characteristics is valuable for an objective analysis in this field of research. It should allow more precise analyses and the construction of typologies that include multi-dimensional sides of governance. We will focus our attention on European metropolises and cities systems taking into account European specificities of towns, territories and political contexts. As described above, the study is based on reviewing the state-of-art of governance theories (transaction cost, path dependency, management efficiency, etc.) and on exploiting literature about cities competitiveness (characteristics of competitive cities, measurements...). Our conceptual development of a scheme of interactions between governance and urban territories will allow to deal with the issue of governance indicators. Our theory will be tested through samples of European cities (> 500.000 inhabitants). Existing databases will allow the processing of many indicators at the European scale. The choice of a set of indicators will be carried out on the basis of discriminating statistical analysis and conceptual model of interaction allowing the reduction of the variables number. The critical analysis will take into account papers from European Commission and national governments about “good governance” and “cities management”. [less ▲]

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