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Peer Reviewed
See detailDiversity and complexity of Early Eukaryotic cells
Javaux, Emmanuelle ULg; Knoll, A. H.; Walter, M.

Conference (2003)

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See detailDiversity and correlation of Givetian records in southern Belgium
Pas, Damien ULg; Poulain, Geoffrey; Labaye, Corentin et al

in Berichte des Institutes für Erdwissenschaften der Karl-Franzens-Universität Graz (2014, August), 19

Detailed reference viewed: 26 (3 ULg)
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See detailDiversity and disparity of the Mesozoic plant fossil record
Cascales - Miñana, Borja ULg; Sender, Luis Miguel; Villanueva-Amadoz, Uxue et al

Conference (2011, September)

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See detailDiversity and endemism of Murinae rodents in Thai limestone karsts
Latinne, Alice ULg; Waengsothorn, Surachit; Rojanadilok, Prateep et al

in Systematics and Biodiversity (2013), 11(3), 323-344

This study aims to investigate the species diversity of rodents living in karst ecosystems of Thailand. A survey has been conducted throughout Thailand, 122 karsts sampled and 477 Murinae rodents live ... [more ▼]

This study aims to investigate the species diversity of rodents living in karst ecosystems of Thailand. A survey has been conducted throughout Thailand, 122 karsts sampled and 477 Murinae rodents live-trapped. Phylogenetic reconstructions were carried out using two mitochondrial markers (cytb, COI). A sequence-based species delimitation method completed by the analysis of the level of genetic divergence was then applied to define species boundaries within our dataset. The phylogenetic position of Niviventer hinpoon was also investigated and sequences obtained from the holotype specimen of this species were used to reliably identify samples of N. hinpoon. A total of 12 described Murinae species, corresponding to 17 deeply divergent genetic lineages, were encountered in limestone karsts of Thailand. Our study revealed an important genetic diversity within the traditionally recognized species Maxomys surifer (four highly divergent genetic lineages), Leopoldamys neilli (two highly divergent genetic lineages) and Berylmys bowersi (two highly divergent genetic lineages). These species could be considered as species complex and require further taxonomic work. This study also provides valuable information on the distribution of the two rodent species endemic to limestone karsts of Thailand, L. neilli and N. hinpoon. Leopoldamys neilli was the most abundant species encountered in Thai karsts during our survey. However, L. neilli specimens from western Thailand are genetically highly divergent from the remaining populations of L. neilli and could represent a separate species. Niviventer hinpoon, phylogenetically closely related to N. fulvescens, is much rarer and its distribution limited to central Thailand. Most of the other captured species are typically associated with forest ecosystems. This study suggests that limestone karsts play a key role in the preservation of the rodent species endemic to such habitat, but they would also provide refuges for the forest-dwelling Murinae rodents in deforested regions. [less ▲]

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See detailDiversity and endemism of Murinae rodents in Thai limestone karsts: a genetic approach
Latinne, Alice ULg

Doctoral thesis (2012)

Limestone karsts are characterized by an important species richness and high levels of endemic species of plants, vertebrates and invertebrates adapted to this extreme environment. However, in Southeast ... [more ▼]

Limestone karsts are characterized by an important species richness and high levels of endemic species of plants, vertebrates and invertebrates adapted to this extreme environment. However, in Southeast Asia, karst ecosystems suffer from a considerable lack of scientific data and remain widely unknown despite their high biological importance. Combining field investigations with phylogeographic and phylogenetic analyses based on several kinds of molecular markers, this thesis aims at exploring the diversity and endemism of Murinae rodents in limestone karsts of Thailand. Thai limestone karsts host two endemic Murinae rodent species, Leopoldamys neilli and Niviventer hinpoon. This thesis reveals that L. neilli is more largely distributed in Thailand than indicated by previous records available in the literature. The species has been recorded in numerous limestone karsts of Thailand with the exception of its peninsular area. L. neilli has also been discovered in central Laos. Moreover our niche modeling study indicates that large tracts of suitable habitat for this species may also occur in several regions of Indochina. L. neilli populations are highly fragmented and a deep genealogical divergence among its lineages is observed. Both mitochondrial and nuclear markers support a large-scale population structure of four main groups (west, centre, north and northeast) and a strong finer structure within each of these groups. These results indicate that L. neilli populations are isolated on karsts such as on islands and that migrations among them are reduced. Our findings also suggest that the current phylogeographic pattern of this species results from the fragmentation of a widespread ancestral population and that vicariance has played a significant role in the evolutionary history of L. neilli. These deep vicariant events that occurred during Plio-Pleistocene are related to the formation of the Central Plain of Thailand. Moreover, the western populations of L. neilli are genetically and morphologically highly divergent from the other populations and could represent a separate species. This strong phylogeographic pattern is not observed for other Murinae species with lower levels of ecological specialization such as Leopoldamys edwardsi and Rattus tanezumi. Finally, this thesis provides preliminary information about the diet of L. neilli and indicates that plants of the Solanaceae family constitute an important part of its diet. The phylogeographic structure of N. hinpoon is not similar to the one of L. neilli. In contrast to L. neilli, N. hinpoon is confined to central Thailand and mitochondrial markers used in this study indicated that this species is genetically homogenous and characterized by a single mitochondrial lineage. Valuable data to refine the conservation status of L. neilli and N. hinpoon, two species currently listed as Data Deficient on the IUCN Red List have been gathered during this study. Three main threats to the long-term subsistence of L. neilli have been identified: (1) the high fragmentation of its population, (2) the large-scale destruction of limestone karsts in Southeast Asia, and (3) the intense trapping of this species for human consumption in northeastern Thailand. Therefore we propose to consider L. neilli as “Near threatened” on the IUCN Red List. However, if the western lineage of L. neilli represents a separate species, it should be listed as “Vulnerable”. Due to its small distribution range and the high threats that its habitat is facing in central Thailand, N. hinpoon would also be qualified as “Vulnerable” on the IUCN Red List. In addition to karst endemic species, this thesis reveals that Thai limestone karsts host high levels of Murinae rodent diversity. A sequence-based species delimitation method completed by the analysis of the level of genetic divergence was used to define species boundaries within our rodent samples collected in limestone karsts. A total of 12 described Murinae species, corresponding to 17 putative species based on our genetic criteria, were encountered in limestone karsts of Thailand. Most of these species are associated to forest ecosystems. Therefore this study suggests that limestone karsts could play a key role in the preservation of the rodent biodiversity by providing refuges for the forest-dwelling Murinae rodents in deforested regions. An important cryptic diversity has been detected within the traditionally recognized species Maxomys surifer and Berylmys bowersi. They could be considered as species complex and require further taxonomic work. The potential distribution of Leopoldamys edwardsi and Leopoldamys sabanus, two species also distributed in Thailand, has been investigated using niche modeling techniques. The predicted distribution ranges of these two species suggest a clear geographical separation between them, with the potential distribution of L. edwardsi being limited to the northern part of Indochina while L. sabanus is mainly distributed in the Sundaic region. Our findings also suggest that these two species could have survived in large areas of Southeast Asia during Quaternary ice ages without large scale extinction and that no drastic modification of the distribution of these species will occur in the future due to climate changes. In conclusion, using various genetic approaches, this work gains important insights into the Murinae rodent diversity of Thai limestone karsts and represents the first detailed study of karst endemic rodent species in Southeast Asia. [less ▲]

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See detailThe diversity and evolution of late-Archean granitoids: Evidence for the onset of “modern-style” plate tectonics between 3.0 and 2.5 Ga
Laurent, Oscar ULg; Martin, Hervé; Moyen, Jean-François et al

in Lithos (2014), 205

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See detailDIVERSITY AND HOST SPECIFICITY OF AZOLLA CYANOBIONTS
Papaefthimiou, Dimitra; Van Hove, Charles; Lejeune, André et al

in Journal of Phycology (2008), 44

A unique, hereditary symbiosis exists between the water fern Azolla and cyanobacteria that reside within a cavity in the dorsal leaf-lobe of the plant. This association has been studied extensively, and ... [more ▼]

A unique, hereditary symbiosis exists between the water fern Azolla and cyanobacteria that reside within a cavity in the dorsal leaf-lobe of the plant. This association has been studied extensively, and questions have frequently been raised regarding the number and diversity of cyanobionts (cyanobacterial symbionts) among the different Azolla strains and species. In this work, denaturating gradient gel electrophoresis (DGGE) and a clone library based on the 16S rRNA gene were used to study the genetic diversity and host specificity of the cyanobionts in 35 Azolla strains covering a wide taxonomic and geographic range. DNA was extracted directly from the cyanobacterial packets, isolated after enzymatic digestion of the Azolla leaves. Our results indicated the existence of different cyanobiont strains among Azolla species, and diversity within a single Azolla species, independent of the geographic origin of the host. Furthermore, the cyanobiont exhibited host-species specificity and showed most divergence between the two sections of genus Azolla, Azolla and Rhizosperma. These findings are in agreement with the recent redefinition of the taxon Azolla cristata within the section Azolla. With regard to the taxonomic status of the cyanobiont, the genus Anabaena of the Nostocaceae family was identified as the closest relative by this work. [less ▲]

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See detailDiversity and pathogenicity of Pseudomonas cichorii isolates causing midrib rot on lettuce
Pauwelyn, E.; Ongena, Marc ULg; Cottyn, B. et al

Conference (2010)

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See detailThe diversity and tolerance to osmotic stress of East Antarctic filamentous Cyanobacteria
Obbels, Dagmar; Verleyen, Elie; Tytgat, Bjorn et al

Poster (2013, July)

Filamentous cyanobacteria are keystone species in Antarctic lake ecosystems; they are the basis of the simple foodwebs, play a crucial role in biogeochemical cycling and form the structure of benthic ... [more ▼]

Filamentous cyanobacteria are keystone species in Antarctic lake ecosystems; they are the basis of the simple foodwebs, play a crucial role in biogeochemical cycling and form the structure of benthic microbial mats which act as habitats for other prokaryotic and (micro-eukaryotic biota. Despite this, little is known about their diversity, adaptation and survival strategies in the extreme Antarctic conditions. We studied the uncultivated prokaryotic diversity using a 454 metagenomic analysis at the 16S rRNA level (V1-V3 region) in Continental Antarctic lakes situated along a conductivity gradient (0.014-142.02 mS/cm). The quality and length of the amplicons was analyzed with a custom-made Mothur pipeline and the resulting sequences were mapped against the Greengenes database, which includes CyanoDB. Almost 27% of the sequences could be assigned to the phylum of the cyanobacteria. The most abundant cyanobacteria in the dataset belonged to the genera Microcoleus, Leptolyngbya, Pseudanabaena, Nodularia and Phormidum. Some 16S rRNA types (at the 97% similarity level), such as sequences related to Leptolynbya antarctica, were present in both freshwater and hypersaline lakes. In order to further investigate this distribution, we isolated filaments of Leptolyngbya from seven lakes with conductivities ranging between 26.8 mS/cm and 0.038 mS/cm. The complete 16S rRNA and ITS genes of the isolates were subsequently sequenced. We found several 16S types related to different lineages of filamentous cyanobacteria in the seven lakes that were supported by ITS data. Two 16S types, belonging to a Leptolyngbya antarctica and Leptolyngbya sp., were each present in two different freshwater lakes. Two different 16S types, both belonging to Leptolynbya antarctica were present in a freshwater and hypersaline lake, which indicates a high ‘intraspecific’ molecular diversity. In order to better understand the adaptation and/or wide tolerance to osmotic stress, we are currently performing ecophysiological experiments with these isolates aimed at assessing the potential local adaptation of these strains to conductivity and desiccation. [less ▲]

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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
Martiniello, Marco ULg; Piquard, Bernadette

Book published by University of Deusto (2002)

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

Conference (2010)

Detailed reference viewed: 22 (4 ULg)
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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 ▲]

Detailed reference viewed: 65 (22 ULg)