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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 dormancy of graminoid and forb species of campo rupestre grasslands
Le Stradic, Soizig ULg; Silveira, Fernando A. O.; Buisson, Elise et al

in Austral Ecology (in press)

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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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See detailDiversity of mechanisms involved in aromatase regulation and estrogen action in the brain
Charlier, Thierry ULg; Cornil, Charlotte ULg; Ball, Gregory et al

in Biochimica et Biophysica Acta - General Subjects (2010)

Background In recent years, the mechanisms through which estrogens modulate neuronal physiology, brain morphology, and behavior have proven to be far more complex than previously thought. For example, a ... [more ▼]

Background In recent years, the mechanisms through which estrogens modulate neuronal physiology, brain morphology, and behavior have proven to be far more complex than previously thought. For example, a second nuclear estrogen receptor has been identified, a new family of coregulatory proteins regulating steroid-dependent gene transcriptions was discovered and, finally, it has become clear that estrogens have surprisingly rapid effects based on their actions on cell membranes, which in turn result in the modulation of intracellular signaling cascades. Scope of review This paper presents a selective review of new findings in this area related to work in our laboratories, focusing on the role of estrogens in the activation of male sexual behavior. Two separate topics are considered. We first discuss functions of the steroid receptor coactivator-1 (SRC-1) that has emerged as a key limiting factor for behavioral effects of estradiol. Knocking-down its expression by antisense oligonucleotides drastically inhibits male-typical sexual behaviors. Secondly, we describe rapid regulations of brain estradiol production by calcium-dependent phosphorylations of the aromatase enzyme, themselves under the control of neurotransmitter activity. These rapid changes in estrogen bioavailability have clear behavioral consequences. Increases or decreases in estradiol concentrations respectively obtained by an acute injection of estradiol itself or of an aromatase inhibitor lead within 15–30 min to parallel changes in sexual behavior frequencies. These new controls of estrogen action offer a vast array of possibilities for discrete local controls of estrogen action. They also represent a formidable challenge for neuroendocrinologists trying to obtain an integrated view of brain function in relation to behavior. [less ▲]

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See detailDiversity of monomers in nonribosomal peptides: towards the prediction of origin and biological activity.
Caboche, Segolene; Leclere, Valerie; Pupin, Maude et al

in Journal of bacteriology (2010), 192(19), 5143-50

Nonribosomal peptides (NRPs) are molecules produced by microorganisms that have a broad spectrum of biological activities and pharmaceutical applications (e.g., antibiotic, immunomodulating, and antitumor ... [more ▼]

Nonribosomal peptides (NRPs) are molecules produced by microorganisms that have a broad spectrum of biological activities and pharmaceutical applications (e.g., antibiotic, immunomodulating, and antitumor activities). One particularity of the NRPs is the biodiversity of their monomers, extending far beyond the 20 proteogenic amino acid residues. Norine, a comprehensive database of NRPs, allowed us to review for the first time the main characteristics of the NRPs and especially their monomer biodiversity. Our analysis highlighted a significant similarity relationship between NRPs synthesized by bacteria and those isolated from metazoa, especially from sponges, supporting the hypothesis that some NRPs isolated from sponges are actually synthesized by symbiotic bacteria rather than by the sponges themselves. A comparison of peptide monomeric compositions as a function of biological activity showed that some monomers are specific to a class of activities. An analysis of the monomer compositions of peptide products predicted from genomic information (metagenomics and high-throughput genome sequencing) or of new peptides detected by mass spectrometry analysis applied to a culture supernatant can provide indications of the origin of a peptide and/or its biological activity. [less ▲]

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See detailDiversity of planktonic cyanobacteria and microcystin occurrence in Polish water bodies investigated using a polyphasic approach
Boutte, Christophe; Mankiewicz-Boczek, Joanna; Komarkova, Jarka et al

in Aquatic Microbial Ecology (2008), 51

Microscopic measurements of fresh biomass and 16S rRNA gene sequences from clone libraries and denaturing gradient gel electrophoresis (DGGE) were used to investigate cyanobacterial diversity in Polish ... [more ▼]

Microscopic measurements of fresh biomass and 16S rRNA gene sequences from clone libraries and denaturing gradient gel electrophoresis (DGGE) were used to investigate cyanobacterial diversity in Polish water bodies in 2002. In addition, measurements of microcystin (MC) concentrations were made. Thirty water samples were taken from 11 water bodies; of these samples, 18 were obtained from the Sulejow Reservoir during regular monitoring from June to October. Intraand extracellular MC concentrations in Sulejow samples were measured by high performance liquid chromatography (HPLC). The extracellular MC concentration was assessed using a protein phosphatase inhibition assay (PPIA) in additional lakes. Additionally, physicochemical parameters were measured (total nitrogen [TN], total phosphorus [TP], TN:TP ratio, chlorophyll a concentration, temperature). In Sulejow, high intracellular MC concentrations corresponded to large cyanobacterial biovolumes and to low TN:TP ratios. In the other lakes, extracellular MCs were not linked to any measured parameters. The combination of the microscopic and molecular data showed that Aphanizomenon and Microcystis were the dominant genera during the summer period in the Sulejow Reservoir. At the genetic level, there was a succession of 2 different operational taxonomic units (OTUs) belonging to the lineage Anabaena/Aphanizomenon. In the other water bodies, the most frequent populations were Aphanizomenon, Anabaena, Microcystis and Planktothrix. Small populations of Romeria, Snowella, Woronichinia, Limnothrix and Pseudanabaena were observed, and an enigmatic cluster affiliated with Prochlorothrix was genetically retrieved. Anabaena and Microcystis were presumed to be the main genera responsible for the MC production. [less ▲]

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See detailDiversity of strophomenid, orthotedid and orthid brachiopods in the Uppermost Famennian (“Strunian"; Upper Devonian) of the Avesnois (Northern France)
Brice, Denise; Nicollin, Jean-Pierre; Mottequin, Bernard ULg

in Annales de la Société Géologique du Nord (2013), 20

In order to contribute to assessment of the aftermath of the Hangenberg Biological Crisis that took place at the top of the Famennian (Upper Devonian), the strophomenid, orthotetid and orthid brachiopods ... [more ▼]

In order to contribute to assessment of the aftermath of the Hangenberg Biological Crisis that took place at the top of the Famennian (Upper Devonian), the strophomenid, orthotetid and orthid brachiopods from the ‘Strunian’-aged Etroeungt Limestone Formation (Avesnois, northern France) are described. The Avesnois is the historical type area of the ‘Strunian’, traditionally considered as the last Famennian substage. Although they are sometimes abundant in the studied sections, their generic and specific diversity is very low in the Etroeungt Limestone Formation. Moreover, the majority of the species belong to long-ranging genera (Leptagonia, Schellwienella?, Schizophoria, Aulacella). [less ▲]

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See detailThe Diversity of the Catalytic Properties of Class a Beta-Lactamases
Matagne, André ULg; Misselyn-Bauduin, A. M.; Joris, Bernard ULg et al

in Biochemical Journal (1990), 265(1), 131-46

The catalytic properties of four class A beta-lactamases were studied with 24 different substrates. They exhibit a wide range of variation. Similarly, the amino acid sequences are also quite different ... [more ▼]

The catalytic properties of four class A beta-lactamases were studied with 24 different substrates. They exhibit a wide range of variation. Similarly, the amino acid sequences are also quite different. However, no relationships were found between the sequence similarities and the substrate profiles. Lags and bursts were observed with various compounds containing a large sterically hindered side chain. As a group, the enzymes could be distinguished from the class C beta-lactamases on the basis of the kappa cat. values for several substrates, particularly oxacillin, cloxacillin and carbenicillin. Surprisingly, that distinction was impossible with the kappa cat./Km values, which represent the rates of acylation of the active-site serine residue by the beta-lactam. For several cephalosporin substrates (e.g. cefuroxime and cefotaxime) class A enzymes consistently exhibited higher kappa cat. values than class C enzymes, thus belying the usual distinction between 'penicillinases' and 'cephalosporinases'. The problem of the repartition of class A beta-lactamases into sub-classes is discussed. [less ▲]

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See detailDiversity of the cyanobacterial communities from the Sør Rondane Mountains (Eastern Antarctica)
Mano, Marie-José ULg; Namsaraev, Zorigto; Fernandez, Rafael et al

Poster (2012, July)

The new Belgian “Princess Elisabeth” research station was built in 2009 and is located 200 km inland in the Western part of the Sør Rondane Mountains (Eastern Antarctica). The BELSPO projects ANTAR-IMPACT ... [more ▼]

The new Belgian “Princess Elisabeth” research station was built in 2009 and is located 200 km inland in the Western part of the Sør Rondane Mountains (Eastern Antarctica). The BELSPO projects ANTAR-IMPACT and BELDIVA aimed to evaluate the diversity and the distribution patterns of the microorganisms from different types of habitats in a radius of 50 km around the Belgian station. These data will serve to follow future anthropogenic and climatic impacts on these communities. Here, we focus on the diversity of cyanobacteria. [less ▲]

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See detailDiversity of the Mechanisms of Resistance to Beta-Lactam Antibiotics
Frère, Jean-Marie ULg; Joris, Bernard ULg; Granier, B. et al

in Research in Microbiology (1991), 142(6, Jul-Aug), 705-10

The sensitivity of a bacterium to beta-lactam antibiotics depends upon the interplay between 3 independent factors: the sensitivity of the essential penicillin-binding enzyme(s), the quantity and ... [more ▼]

The sensitivity of a bacterium to beta-lactam antibiotics depends upon the interplay between 3 independent factors: the sensitivity of the essential penicillin-binding enzyme(s), the quantity and properties of the beta-lactamase(s) and the diffusion barrier that the outer-membrane of Gram-negative bacteria can represent. Those three factors can be modified by mutations or by the horizontal transfer of genes or portions of genes. [less ▲]

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See detailDiversity of toxin and non-toxin containing cyanobacterial mats of meltwater ponds on the Antarctic Peninsula: a pyrosequencing approach
Kleinteich, Julia ULg; Hildebrand, F.; Wood, S. A. et al

in Antarctic Science (2014), 26(05), 521--532

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See detailDiversity patterns of the vascular plant group Zosterophyllopsida
Cascales - Miñana, Borja ULg; Meyer-Berthaud, Brigitte

Conference (2014, August)

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See detailDiversity patterns of the vascular plant group Zosterophyllopsida in relation to Devonian palaeogeography
Cascales - Miñana, Borja ULg; Meyer-Berthaud, Brigitte

in Palaeogeography, Palaeoclimatology, Palaeoecology (2015), 423

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See detailDiversity policies in Belgium
Cornet, Annie ULg; Zanoni, P.

in KLARSFELD, A. (Ed.) International handbook on diversity management at work (2010)

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See detailDiversity policy in employment and service provision - Case study: Antwerp, Belgium
Gsir, Sonia ULg

Report (2009)

Antwerp is the largest city in Flanders and its population comprises around 13% foreigners. Yet a quarter of the inhabitants have a migration background and they represent 30% of the working population ... [more ▼]

Antwerp is the largest city in Flanders and its population comprises around 13% foreigners. Yet a quarter of the inhabitants have a migration background and they represent 30% of the working population. Until recently, the diversity policy adopted by the city focused on specific target groups – people with a migration background was one of them. It was a categorial diversity policy. And specific departments were in charge to stimulate and support the policy through specific measures and actions with respect to each specific target group. The Integration Service and in particular the IS diversity consultants developed intensive contacts with some other services such as the Urban Poverty Department. The main challenges remain the language barriers and the recruitment procedures of the city. [less ▲]

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See detailDiversity policy in employment and service provision - Case study: Valencia, Spain
Gsir, Sonia ULg

Report (2009)

The city of Valencia has a population of 807,396 inhabitants and is the centre of an extensive metropolitan area which brings the number to a million and a half people. This total represents 18% of the ... [more ▼]

The city of Valencia has a population of 807,396 inhabitants and is the centre of an extensive metropolitan area which brings the number to a million and a half people. This total represents 18% of the population of the Valencian region and makes Valencia, in terms of population, the third largest city in Spain after Madrid and Barcelona. It is also the third largest city in terms of registered immigrants. Foreign nationals – just as Spaniards – have to register in the municipal census. The city population increased throughout the 20th century and was stable during the 1990s. At the beginning of the 21st century, a strong migratory inflow has led to a new dynamic increase in the population. [less ▲]

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