How far and how fast do bryophytes travel at the landscape scale?
Hutsemekers, Virginie ; Dopagne, Claude ; Vanderpoorten, Alain
in Diversity & Distributions (2008), 14(3), 483-492
Dispersal ability is a factor of prime importance to explain biotic distributions. Yet, it is extremely difficult to measure directly. In this study, we take advantage of the natural experimental design ... [more ▼]
Dispersal ability is a factor of prime importance to explain biotic distributions. Yet, it is extremely difficult to measure directly. In this study, we take advantage of the natural experimental design of slag heap colonization in Belgium to document the timing and range of dispersal of bryophytes at the landscape scale. On the basis of a species atlas with a 4 × 4 km grid, the minimum distance separating species found on 52 slag heaps from potential source populations was determined. Minimum dispersal rates were inferred by coupling the information on minimum distance between slag heap and source populations with time since colonization. The number of species per slag heap is significantly correlated with time since colonization and area size. The frequency distribution of the longest dispersal events is highly skewed, with 44% of the species recruited within the nearest 6 km. In the remaining 56% of the species, recruitments from source populations located within a range of at least 6–86 km occurred within a period of less than 50 years. The majority of the species that are not recruited within the nearest vicinity of the slag heaps, including rare species at the regional scale, occur on slag heaps that have been colonized for 25–50 years. Most recently colonized slag heaps are indeed characterized by 'fugitive', weedy species, whereas slag heaps that have been colonized for > 50 years tend to accumulate perennial species with a 'stayer' life strategy. These observations suggest that rare species may display the dispersal ability to travel across the landscape, but are subsequently limited by their ability to establish a viable community because of more competitive neighbours. Rare species therefore tend to accumulate at intermediate colonization stages, which represent a trade-off between an increasing probability of colonization with time and a decreasing probability of establishment due to competition. [less ▲]Detailed reference viewed: 40 (4 ULg)
How fertilizer and soil nitrogen are distributed into winter wheat plant
; Destain, Jean-Pierre ; Bodson, Bernard et al
(2007, September 16)Detailed reference viewed: 20 (0 ULg)
How good are we at extracting personal information from voices?
Dehon, Hedwige ;
Poster (2009, June)Detailed reference viewed: 3 (0 ULg)
How HTLV-1 may subvert miRNAs for persistence and transformation.
Bouzar, Amel ; Willems, Luc
in Retrovirology (2008), 5
Distinct mechanisms are used by viruses to interact with cellular miRNAs. The role of microRNAs in viral replication and persistence ranges from viral-encoded microRNAs to suppressors of RNA interference ... [more ▼]
Distinct mechanisms are used by viruses to interact with cellular miRNAs. The role of microRNAs in viral replication and persistence ranges from viral-encoded microRNAs to suppressors of RNA interference. Viruses can also exploit cellular miRNAs for influencing cellular metabolism to ensure efficient replication or latency. In particular, two recent studies provide examples of how HTLV-1 may co-opt or subvert cellular miRNAs for persistent replication and oncogenic purposes. The pathways modulated by these described miRNAs are critically involved in apoptosis, proliferation and innate immune response. [less ▲]Detailed reference viewed: 58 (29 ULg)
How I explore the benefit of 3D/4D ultrasound in obstetrics
Chantraine, Frédéric ; Schaaps, Jean-Pierre ; Foidart, Jean-Michel
in Revue Médicale de Liège (2008), 63(3), 153-7
During recent years, 3D has become an important tool in ultrasound. In obstetrics, the classic 2D examination with Doppler is now often completed by 3D. In this article the strengths and weaknesses of ... [more ▼]
During recent years, 3D has become an important tool in ultrasound. In obstetrics, the classic 2D examination with Doppler is now often completed by 3D. In this article the strengths and weaknesses of this technique are discussed. [less ▲]Detailed reference viewed: 80 (3 ULg)
How institutional theory can contribute to understand social entrepreneurship. Illustrations from microfinance
Conference (2009)Detailed reference viewed: 66 (1 ULg)
How Intellectual Capital Influences Innovation in Belgian Luxury Houses
Riguelle, France ; Van Caillie, Didier
Conference (2013, June)
Since almost three decades, luxury houses have been tackling the increasing importance of groups and of private investment funds specialized in the luxury sector (Roux & Floch, 1996). Therefore innovation ... [more ▼]
Since almost three decades, luxury houses have been tackling the increasing importance of groups and of private investment funds specialized in the luxury sector (Roux & Floch, 1996). Therefore innovation has become an important source of value creation and of competitive advantage for them (Chevallier & Mazzalovo, 2008; Kapferer & Bastien, 2009). Reciprocally, luxury houses usually demonstrate a strong intellectual capital according to the definitions of Bontis (1998). Although the impact of intellectual capital on innovation has been widely demonstrated by scholars in a general scope (Subramaniam & Youndt, 2005), the existence and the nature of this influence has not been investigated in the luxury sector yet. The aim of our research is to highlight if a causal relationship exists in Belgian luxury houses, in order to validate or invalidate the results obtained by Subramaniam & Youndt (2005) and by Wu, Chang, & Chen (2008) within the luxury sector. [less ▲]Detailed reference viewed: 20 (4 ULg)
How King Leopold II used Emile de Laveleye’s intellectual network for the benefit of his African project…
Conference (2010, May 20)
The “Belle Epoque” saw the revival of the colonial idea in new forms. A second European colonization wave washed over Africa. King Leopold II unfolded his activities in Congo from 1876 onwards. There, his ... [more ▼]
The “Belle Epoque” saw the revival of the colonial idea in new forms. A second European colonization wave washed over Africa. King Leopold II unfolded his activities in Congo from 1876 onwards. There, his efforts to develop a so-called “philanthropic” enterprise soon evolved in a process of state formation, overshadowed by intrigues and tensions that were a consequence of colonial competition between the western powers. Only a decade later, at the Berlin Conference of 1885, a definite arrangement was adopted. Everywhere in Europe, a disputed transition was made from liberal to more conservative ways of government. Of course this tension field also dominated intellectual life. There was an intense debate between partisans of colonialism and supporters of worldwide free trade. For the development of his colonial doctrine Leopold II had been inspired by intellectuals that supported economic expansionism. Most of them were active in the field of economic geography. But the King also searched for support in other academic circles and mobilized one of Europe’s brightest minds to join him in his quest for the most adequate economic, social and political model of a future state in the heart of Africa. In his books, articles and pamphlets, the liberal minded political economist Emile de Laveleye (1822-1892) – an opinion maker of European renown – showed himself an unshakable opponent of colonization and imperialism. However, in the period 1875-1885 – a decade so crucial for Congo – a surprising intellectual rapprochement between de Laveleye and Leopold II was established. For a certain time, this competent man of science advised the King, for example at the International Geographical Conference in Brussels, putting into royal service an intellectual network of European range. This paper investigates how, in the complex and constantly evolving public discussion about Congo, two apparently opposing minds attracted each other. Analyzing de Laveleye’s publications and correspondence we focus on his important pleas for a “neutral and international formula” that would place Leopold II in a conflicting situation with Portugal and France, countries that claimed Congo’s estuary for their own benefit. De Laveleye believed that Leopold was sincere about his civilizing mission and crusade against slavery. This study shows how, in the years preceding the Berlin Conference, de Laveleye got actively involved in a carefully orchestrated European media campaign in support of Leopold’s initiative. It was there that his intellectual circle became extremely useful and was fully implicated. His contacts in the world of law, especially among experts of international law, contributed to the important discussions about Congo’s juridical status. De Laveleye’s colleague Sir Travers Twiss, one of the most reputed jurists of that time, as well as the influential Institut de Droit international, of which de Laveleye had been one of the founders, entered the debate zone and took positions that were favorable for Leopold’s project. With this new approach, our paper also aims to give insight in the way Leopold II transformed his own reasoning into a more authoritative set of practical standards that were shared by an intellectual elite. [less ▲]Detailed reference viewed: 35 (5 ULg)
How landscapes change: human disturbance and ecosystem fragmentation in the Americas (G.A. Bradshaw, P.A. Marquet).
in Landscape Research (2004), 29(1), 101-102Detailed reference viewed: 7 (0 ULg)
How large is the Io UV footprint?
Bonfond, Bertrand ; Grodent, Denis ; Gérard, Jean-Claude et al
Located close to the feet of the magnetic field lines connecting Io to each Jovian hemisphere, the Io footprint is the auroral signature of the electromagnetic interaction between Io and Jupiter's ... [more ▼]
Located close to the feet of the magnetic field lines connecting Io to each Jovian hemisphere, the Io footprint is the auroral signature of the electromagnetic interaction between Io and Jupiter's magnetosphere. It consists of several spots followed downstream by an extended tail. The size of the main spot is expected to scale to the size of the interaction region close to Io. Consequently, this quantity is crucial to understand the processes involved. However, the main spot size is a controversial issue as previously published values range from ~400 km to ~10000 km, leading to contradictory conclusions. Based on observations carried on with the Hubble Space Telescope STIS and ACS FUV instruments from 1997 to 2009, we estimate the size of the main footprint spot on a much larger image sample than previously. Additionally, we carefully selected the images in order to avoid viewing geometry ambiguities when measuring the spatial extent of the different features. The main spot length along the footpath is ~900 km while its width perpendicular to the footpath is <200 km. The spot length is larger than the projected diameter of Io along unperturbed magnetic field lines, which appears to be consistent with recent simulations. The vertical extent and the peak altitude of the main spot are similar to those measured in the tail. Nevertheless, the secondary spot attributed to trans-hemispheric electron beams has been measured to peak at ∼200 km below the main spot and the tail, which confirms their different origins. [less ▲]Detailed reference viewed: 26 (0 ULg)
How licensing can address new challenges? The question of brokering
Conference given outside the academic context (2010)Detailed reference viewed: 18 (1 ULg)
How Mannheimia haemolytica defeats host defence through a kiss of death mechanism
Zecchinon, Laurent ; Fett, Thomas ; Desmecht, Daniel
in Veterinary Research (2005), 36(Mar-Apr), 133-156
Mannheimia haemolytica induced pneumonias are only observed in goats, sheep and cattle. The bacterium produces several virulence factors,whose principal ones are lipopolysaccharide and leukotoxin. The ... [more ▼]
Mannheimia haemolytica induced pneumonias are only observed in goats, sheep and cattle. The bacterium produces several virulence factors,whose principal ones are lipopolysaccharide and leukotoxin. The latter is cytotoxic only for ruminant leukocytes, a phenomenon that is correlated with its ability to bind and interact with the ruminant beta2-integrin Lymphocyte Function-associated Antigen 1. This paper globally reviews all the information available on host-pathogen interactions underlying respiratory mannheimiosis (formerly pasteurellosis), from the stable and the Petri dish to the biochemical cascade of events triggered by the leukotoxin inside ruminant leukocytes. One conclusion can be made: the most widespread cattle respiratory disease with the most important impact on beef production worldwide, is probably due to a tiny ruminant-specific focal variation in the CD18- and/or CD11a-expressing genes. [less ▲]Detailed reference viewed: 20 (1 ULg)
How many nursery pigs can eat at one wet/dry feeder space
Laitat, Martine ;
Article for general public (2002)Detailed reference viewed: 12 (0 ULg)
How many scribes worked on the Egyptian Recension of the Thouand and One Nights?...
Conference (2013, October 11)Detailed reference viewed: 10 (1 ULg)
How many species in the Black rat complex (Rattus rattus sensu lato) in Southeast Asia?
Pagès, Marie ; ; et al
Conference (2011, July)
Black rats are among the major invasive vertebrates with severe ecological, economic and health impacts. Remarkably, the evolutionary history of black rats has received little attention and there is no ... [more ▼]
Black rats are among the major invasive vertebrates with severe ecological, economic and health impacts. Remarkably, the evolutionary history of black rats has received little attention and there is no firm agreement as how many species should be recognized within the Rattus rattus complex. Members of the species complex are native from India and Southeast Asia. Current taxonomy suggests that four taxa live in sympatry in several places of Thailand and Cambodia where the present study was conducted: three accepted species (R. tanezumi, R. losea, R. argentiventer) and an additional lineage of unclear taxonomic status sometimes referred as Rattus R3. We used an extensive sampling, morphological data and diverse genetic markers of different evolutionary rates and parental inheritance (two mtDNA genes, one nuclear gene and eight microsatellite loci) to assess the genetic structure among the four taxa. Genetic analyses revealed discordant patterns between the mt and the nuclear data. The mt phylogeny identified three reciprocally monophyletic clades corresponding to the four putative taxa while the nuclear phylogeny failed to separate tanezumi and R3. Within geographic localities, microsatellites revealed free gene flow between tanezumi and R3 but no gene flow between those two taxa and losea or argentiventer. Altogether theses analyses do not support the taxon R3 as a valid species and advocate for synonymy with tanezumi. As a consequence, R. tanezumi becomes paraphyletic with respect to losea. Simulation analyses are now ongoing to determine whether a recent speciation event between tanezumi and losea, or an incomplete lineage sorting within tanezumi could explain this uncommon pattern. [less ▲]Detailed reference viewed: 22 (1 ULg)
How many women can benefit from a full intrapartum antibiotic prphylaxis for prevention of perinatal group B streptococcal disease?
MELIN, Pierrette ; ; et al
in American Society of Microbiology (Ed.) Program and Abstracts of the 44th Intersciences Conference on Antimicrobial Agents and Chemotherapy (2004, November)
Background: In Belgium as in many Western countries, GBS are still the leading cause of severe perinatal infections. Current guidelines for prevention recommend intrapartum antimicrobial prohylaxis (IAP ... [more ▼]
Background: In Belgium as in many Western countries, GBS are still the leading cause of severe perinatal infections. Current guidelines for prevention recommend intrapartum antimicrobial prohylaxis (IAP) administered promptly before delivery to pregnant women colonized with GBS. The risk of vertical GBS transmission to the newborn decreases as the duration of prophylaxis increases. The considered threshold for prophylaxis adequacy is the first dose administered at least 4 hours before delivery. Objective: To evaluate the proportion of pregnant women who could benefit from an adequate IAP for the prevention of GBS perinatal infections. Methods: Between June and October 2003, we recorded in two hospitals the elapse time between admission for labor and delivery. We assumed 5 hours represent a useful threshold to allow admission, revision of chart and administration of adequate IAP. The status of vaginal colonization with GBS was determined by CDC’s recommended culture method with Granada agar added. Results: Among 532 women, 27.3 % delivered within 5 hours after admission for labor. The colonization rate for GBS was 25.6 %. The distribution of elapse time between admission and delivery for GBS colonized pregnant women was not significantly different from non colonized women (p <= 1). Conclusions: 1) With the current prevention strategy, 27.3 % of these pregnant women would not have benefit from adequate prophylaxis 2) These results highlight the importance of an efficient organization to warranty prompt administration of IAP as soon as possible when mandatory. 3) If a rapid intrapartum screening test is used, no delay can be afforded “from ward to bench to bed”. [less ▲]Detailed reference viewed: 14 (1 ULg)
How measuring glomerular filtration rate? Comparison of reference methods
in Sahay, Manisha (Ed.) Basic Nephrology and Acute Kidney Injury (2012)Detailed reference viewed: 13 (0 ULg)
How Measuring Glomerular Filtration Rate? Comparison of reference methods
in Sahay, Manisha (Ed.) Basic Nephrology and Acute Kidney injury (2012)Detailed reference viewed: 13 (6 ULg)