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See detailOccurrence of bottlenose dolphins (Tursiops truncatus) in the Río Negro Estuary, Argentina, and their mid-distance movements along the Northeast Patagonian coast
Failla, Mauricio; Seijas, Veronica; Vermeulen, Els ULg

in Latin American Journal of Aquatic Mammals (in press)

A systematic study on the presence of bottlenose dolphins (Tursiops truncatus) in the Río Negro Estuary (RNE), Patagonia Argentina, was carried out between the months March – July from 2008 to 2011. Data ... [more ▼]

A systematic study on the presence of bottlenose dolphins (Tursiops truncatus) in the Río Negro Estuary (RNE), Patagonia Argentina, was carried out between the months March – July from 2008 to 2011. Data on the dolphin’s activity patterns were gathered via an Ad Libitum focal group sampling mode accompanying dorsal fin images taken for identification and re-identification of individuals. A total effort of 188 h resulted in 58 h of positive observation of 124 dolphin groups (sightings per unit effort (SPUE) = 0.66 groups/h). Data analysis showed two main activity states for the observed groups, travelling (65%) and foraging (26%). The remaining 9% of the groups were involved in other activity states. The photo-identification effort, which started opportunistically in 2006, resulted in a catalogue of 21 individual dolphins, with a total mean re-identification rate of 9 days (max = 24 days). When comparing these pictures to the existing catalogue of Bahía San Antonio (approximately 200 km west from the study area) dorsal fins of 20 individuals could be positively matched and most (n = 17) could be subsequently re-identified in both areas, indicating their long distance movements along the North Patagonian coast during the austral autumn months. This season coincides with the lowest amount of feeding activity observed in Bahía San Antonio. This study suggests that bottlenose dolphins enter RNE, mainly during autumn, to forage. It appears that the search for food resources may be the trigger for their movement patterns along the North Patagonian coast during this season, at least for certain individuals. More research is needed to accurately confirm this hypothesis. [less ▲]

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See detailCodifying ‘Sacred Laws’ in Ancient Greece
Carbon, Jan-Mathieu ULg; Pirenne-Delforge, Vinciane ULg

in Jaillard, Dominique; Nihan, Christophe (Eds.) Legal Codification in Ancient Greece and Ancient Israel (in press)

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See detailThe Twelve Years Truce (1609-1621): Archdukes' confessors, spirituality and politics in Flanders.
Pirlet, Pierre-François ULg

in Libros de la corte (in press)

Iñigo de Brizuela and Andrés de Soto, both confessors of the Archdukes were key figures at Brussels' court. Each of them used to influence the policy, using different bias. But they weren't trying to ... [more ▼]

Iñigo de Brizuela and Andrés de Soto, both confessors of the Archdukes were key figures at Brussels' court. Each of them used to influence the policy, using different bias. But they weren't trying to reach similar goals: Brizuela carefully acted to preserve Spanish interests in the Catholic Netherlands, while de Soto struggled for a Catholic victory. Their political actions and its reasons will be covered by this paper. [less ▲]

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See detailExperimental and numerical study of the flight of geese
Dimitriadis, Grigorios ULg; Gardiner, James; Tickle, Peter et al

in Aeronautical Journal (in press)

The flight of barnacle geese at airspeeds representing high-speed migrating flight is investigated using experiments and simulations. The experimental part of the work involved the filming of three ... [more ▼]

The flight of barnacle geese at airspeeds representing high-speed migrating flight is investigated using experiments and simulations. The experimental part of the work involved the filming of three barnacle geese (Branta Leucopsis) flying at different airspeeds in a wind tunnel. The video footage was analysed in order to extract the wing kinematics. Additional information, such as wing geometry and camber was obtained from a 3D scan of a dried wing. An unsteady vortex lattice method was used to simulate the aerodynamics of the measured flapping motion. The simulations were used in order to successfully reproduce the measured body motion and thus obtain estimates of the aerodynamic forces acting on the wings. It was found that the mean of the wing pitch angle variation with time has the most significant effect on lift while the difference in the durations of the upstroke and downstroke has the major effect on thrust. The power consumed by the aerodynamic forces was also estimated; it was found that increases in aerodynamic power correspond very closely to climbing motion and vice versa. Root-mean-square values of the power range from 100 W to 240 W. Finally, it was observed that tandem flying can be very expensive for the trailing bird. [less ▲]

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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 (in press)

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See detailTasting the World. A Cultural History of Taste in the Early Modern Era
Von Hoffmann, Viktoria ULg

Book published by University of Illinois Press (in press)

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See detailWorking memory deficits in developmental dyscalculia: the importance of serial order.
Attout, Lucie ULg; Majerus, Steve ULg

in Child Neuropsychology : A Journal on Normal & Abnormal Development in Childhood & Adolescence (in press)

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See detailHow do harpacticoid copepods colonize detrital seagrass leaves?
Mascart, Thibaud ULg; Agusto, Laura; Lepoint, Gilles ULg et al

in Marine Biology (in press)

An experiment was carried out investigating the colonization ability and specific pattern of copepods towards a provisional benthic habitat. Since copepods are known to disperse passively and actively ... [more ▼]

An experiment was carried out investigating the colonization ability and specific pattern of copepods towards a provisional benthic habitat. Since copepods are known to disperse passively and actively, the experiment aimed to investigate the pool of colonizers of macrophytodetritus and the species-specific active colonization pathways. The experiment was performed in a Mediterranean seagrass Posidonia oceanica meadow on defaunated macrophytodetritus accumulations (mainly dead seagrass leaves) for two time intervals (24 h and 96 h). Active colonization by copepods, independently of their adjacent potential source pool habitat (bare sandy sediments, P. oceanica canopy, water column and macrophytodetritus) occurred within 24 h. Natural densities (as in the control treatments) were only reached by active colonization through the water column. Both neither diversities nor species composition of natural macrophytodetritus were ever reached by one single migratory pathway, therefore only a combination of interstitial migration and water column migration can explain the species occurrence under natural condition. Moreover, every potential adjacent source pool habitat, contributed species to the newly colonized macrophytodetritus. However, the main colonizers were mostly species with good swimming capabilities. The diverse pool of species present in the newly colonized macrophytodetritus underlines the complex communities and dispersion capabilities of copepods. Hence, macrophytodetritus possesses the potential ability to be a colonizer source pool for every adjacent habitat and thus behaves as a copepod hub for the entire seagrass ecosystem. [less ▲]

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See detailAnother Generalization of Abelian Equivalence: Binomial Complexity of Infinite Words (long version)
Rigo, Michel ULg; Salimov, Pavel

in Theoretical Computer Science (in press)

The binomial coefficient of two words $u$ and $v$ is the number of times $v$ occurs as a subsequence of $u$. Based on this classical notion, we introduce the $m$-binomial equivalence of two words refining ... [more ▼]

The binomial coefficient of two words $u$ and $v$ is the number of times $v$ occurs as a subsequence of $u$. Based on this classical notion, we introduce the $m$-binomial equivalence of two words refining the abelian equivalence. Two words $x$ and $y$ are $m$-binomially equivalent, if, for all words $v$ of length at most $m$, the binomial coefficients of $x$ and $v$ and respectively, $y$ and $v$ are equal. The $m$-binomial complexity of an infinite word $x$ maps an integer $n$ to the number of $m$-binomial equivalence classes of factors of length $n$ occurring in $x$. We study the first properties of $m$-binomial equivalence. We compute the $m$-binomial complexity of two classes of words: Sturmian words and (pure) morphic words that are fixed points of Parikh-constant morphisms like the Thue--Morse word, i.e., images by the morphism of all the letters have the same Parikh vector. We prove that the frequency of each symbol of an infinite recurrent word with bounded $2$-binomial complexity is rational. [less ▲]

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See detailDefining multiplication in some additive expansions of polynomial rings
Point, Françoise; Rigo, Michel ULg; Waxweiler, Laurent

in Communications in Algebra (in press)

Adapting a result of R. Villemaire on expansions of Presburger arithmetic, we show how to define multiplication in some expansions of the additive reduct of certain Euclidean rings. In particular, this ... [more ▼]

Adapting a result of R. Villemaire on expansions of Presburger arithmetic, we show how to define multiplication in some expansions of the additive reduct of certain Euclidean rings. In particular, this applies to polynomial rings over a finite field. [less ▲]

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See detailAn analogue of Cobham's theorem for graph directed iterated function systems
Charlier, Emilie ULg; Leroy, Julien ULg; Rigo, Michel ULg

in Advances in Mathematics (in press)

Feng and Wang showed that two homogeneous iterated function systems in $\mathbb{R}$ with multiplicatively independent contraction ratios necessarily have different attractors. In this paper, we extend ... [more ▼]

Feng and Wang showed that two homogeneous iterated function systems in $\mathbb{R}$ with multiplicatively independent contraction ratios necessarily have different attractors. In this paper, we extend this result to graph directed iterated function systems in $\mathbb{R}^n$ with contraction ratios that are of the form $\frac{1}{\beta}$, for integers $\beta$. By using a result of Boigelot {\em et al.}, this allows us to give a proof of a conjecture of Adamczewski and Bell. In doing so, we link the graph directed iterated function systems to Büchi automata. In particular, this link extends to real numbers $\beta$. We introduce a logical formalism that permits to characterize sets of $\mathbb{R}^n$ whose representations in base $\beta$ are recognized by some Büchi automata. This result depends on the algebraic properties of the base: $\beta$ being a Pisot or a Parry number. The main motivation of this work is to draw a general picture representing the different frameworks where an analogue of Cobham's theorem is known. [less ▲]

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See detailGlioblastoma-derived extracellular vesicles induce tumor-supportive phenotypes in monocytic cells
de Vrij, Jeroen; Maas, Sybren; Kwappenberg, Kitty et al

in International Journal of Cancer = Journal International du Cancer (in press)

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See detailHigh Resolution postontrast time of flight MR angiography of intracranial perforators at 7.0 Tesla
Harteveld, A; de Cocker, L; Dieleman, N et al

in American Journal of Neuroradiology (in press)

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See detailFish consumption patterns and hair mercury levels in children and their mothers in 17 EU countries
Castano, Argelia; Cutanda, Francisco; Esteban, Marta et al

in Environmental Research (in press)

The toxicity of methylmercury (MeHg) in humans is well established and the main source of exposure is via the consumption of large marine fish and mammals. Of particular concern are the potential ... [more ▼]

The toxicity of methylmercury (MeHg) in humans is well established and the main source of exposure is via the consumption of large marine fish and mammals. Of particular concern are the potential neurodevelopmental effects of early life exposure to low-​levels of MeHg. Therefore, it is important that pregnant women, children and women of childbearing age are, as far as possible, protected from MeHg exposure. Within the European project DEMOCOPHES, we have analyzed mercury (Hg) in hair in 1799 mother-​child pairs from 17 European countries using a strictly harmonized protocol for mercury anal. Parallel, harmonized questionnaires on dietary habits provided information on consumption patterns of fish and marine products. After hierarchical cluster anal. of consumption habits of the mother-​child pairs, the DEMOCOPHES cohort can be classified into two branches of approx. similar size: one with high fish consumption (H) and another with low consumption (L)​. All countries have representatives in both branches, but Belgium, Denmark, Spain, Portugal and Sweden have twice as many or more mother-​child pairs in H than in L. For Switzerland, Czech Republic, Hungary, Poland, Romania, Slovenia and Slovakia the situation is the opposite, with more representatives in L than H. There is a strong correlation (r=0.72) in hair mercury concn. between the mother and child in the same family, which indicates that they have a similar exposure situation. The clustering of mother-​child pairs on basis of their fish consumption revealed some interesting patterns. One is that for the same sea fish consumption, other food items of marine origin, like seafood products or shellfish contribute significantly to the mercury levels in hair. We conclude that addnl. studies are needed to assess and quantify exposure to mercury from seafood products, in particular. The cluster anal. also showed that 95​% of mothers who consume once per wk fish only, and no other marine products, have mercury levels 0.55 μg​/g. Thus, the 95th percentile of the distribution in this group is only around half the US-​EPA recommended threshold of 1 μg​/g mercury in hair. Consumption of freshwater fish played a minor role in contributing to mercury exposure in the studied cohort. The DEMOCOPHES data shows that there are significant differences in MeHg exposure across the EU and that exposure is highly correlated with consumption of fish and marine products. Fish and marine products are key components of a healthy human diet and are important both traditionally and culturally in many parts of Europe. Therefore, the communication of the potential risks of mercury exposure needs to be carefully balanced to take into account traditional and cultural values as well as the potential health benefits from fish consumption. European harmonized human biomonitoring programs provide an addnl. dimension to national HMB programs and can assist national authorities to tailor mitigation and adaptation strategies (dietary advice, risk communication, etc.) to their country's specific requirements. [less ▲]

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See detailÉclairer les enjeux de la reconstruction industrielle du bassin liégeois : l'apport des archives des Etablissements insalubres et dangereux (1919-1925)
Peters, Arnaud ULg; Defechereux, Olivier ULg; Destatte, Julien ULg

in Parmentier, Isabelle (Ed.) Actes des Deuxièmes Rencontres d'Histoire de l'Environnement en Belgique (Belgique, Luxembourg, Congo, Rwanda, Burundi) (in press)

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See detailThe utility of Google Scholar when searching geographical literature: comparison with three commercial bibliographic databases
Stirbu, Simona ULg; Thirion, Paul ULg; Schmitz, Serge ULg et al

in Journal of Academic Librarianship (in press)

This study aims to highlight what benefits, if any, Google Scholar (GS) has for academic literature searches in the field of geography, compared to three commercial bibliographic databases: Web of Science ... [more ▼]

This study aims to highlight what benefits, if any, Google Scholar (GS) has for academic literature searches in the field of geography, compared to three commercial bibliographic databases: Web of Science (WoS) and FRANCIS (multidisciplinary databases) and GeoRef (specialized in geosciences). To ensure a valid comparison, identical bibliographic searches were applied using each of the four bibliographic tools. To exclude automatic variations of the ten keywords tested, they were placed between quotation marks and searched only in the “title” field of the respective search tools’ interfaces. The results were limited to bibliographic references published from 2005 to 2009. In order to assess the repeatability of the results, the exact same process was repeated monthly between November 2010 and July 2011. Initially the whole set of results was analyzed, after which the search results for two keywords (selected since they yielded a manageable number of results) were studied in more detail. The results indicate that GS search results show a large degree of overlap with those of the other databases but, moreover, yield numerous unique hits, which should be useful to researchers in both the fields of human and physical geography. GS leads the other tools widely on number of results, independently of keyword, subfield, year of publication, or time of search. [less ▲]

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See detailUsing kernels and ecological niche modelling to delineate conservation areas in an endangered patch-breeding phenotype
Denoël, Mathieu ULg; Ficetola, Francesco

in Ecological Applications (in press)

Efficient delineation of conservation areas is a great challenge in maintaining biodiversity. Kernel density estimators (KDEs) are a powerful tool in this perspective, but they have not been applied at ... [more ▼]

Efficient delineation of conservation areas is a great challenge in maintaining biodiversity. Kernel density estimators (KDEs) are a powerful tool in this perspective, but they have not been applied at the population level on patch-distributed organisms. This would be particularly worthy for species that need broad habitats beyond those where they can be sampled; such as terrestrial lands for pond-breeding amphibians. The aim of this study was to compare different approaches for the identification of suitable areas for conservation: KDE, ecological niche modelling, and a combination of KDE and niche models. Paedomorphosis was chosen as a model system because this is an important form of intraspecific variation that is present in numerous taxa, but geographically localized within species and globally endangered. 277 ponds were sampled in one of the hotspots of paedomorphosis to determine the abundance and distribution of paedomorphs (i.e. individuals retaining gills at the adult stage) of the palmate newt (Lissotriton helveticus), with emphasis on the connections between the most valuable populations. KDEs gave insights into the surface areas required to balance the maintenance of certain number of connected ponds and the respective number of disjoint areas in which the whole population is divided. The inclusion of barriers in the models helped in accurately designing the limits of the areas to protect. Alone, habitat models were not able to successfully delineate the area to protect, but the integration between terrestrial suitable areas or barriers and KDE allowed an objective identification of areas required for conservation. Overall, the best performance was observed by the KDE integrating ecological barriers, and by the combination between KDE and niche modelling. In a broader perspective, KDEs are thus a pertinent tool in providing quantitative spatial measurements to delineate conservation areas based on patch-abundance data with a specific focus to connectivity. [less ▲]

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See detailMoyens et enjeux d’une approche didactique des Illuminations
Saint-Amand, Denis ULg

in Parade Sauvage (in press), 25

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See detailTowards a framework for assessment and management of cumulative human impacts on marine food webs
Giakoumi, Sylvaine; Halpern, Benjamin S.; Michel, Loïc ULg et al

in Conservation Biology (in press)

Effective ecosystem-based management requires understanding ecosystem responses to multiple human threats, rather than focusing on single threats. To understand ecosystem responses to anthropogenic ... [more ▼]

Effective ecosystem-based management requires understanding ecosystem responses to multiple human threats, rather than focusing on single threats. To understand ecosystem responses to anthropogenic threats holistically, it is necessary to know how threats affect different components within ecosystems and ultimately alter ecosystem functioning. We used a case study of a Mediterranean seagrass (Posidonia oceanica) food web and expert knowledge elicitation in an application of the initial steps of a framework for assessment of cumulative human impacts on food webs. We produced a conceptual seagrass food web model, determined the main trophic relationships, identified the main threats to the food web components, and assessed the components’ vulnerability to those threats. Some threats had high (e.g., coastal infrastructure) or low impacts (e.g., agricultural runoff) on all food web components, whereas others (e.g., introduced carnivores) had very different impacts on each component. Partitioning the ecosystem into its components enabled us to identify threats previously overlooked and to reevaluate the importance of threats commonly perceived as major. By incorporating this understanding of system vulnerability with data on changes in the state of each threat (e.g., decreasing domestic pollution and increasing fishing) into a food web model, managers may be better able to estimate and predict cumulative human impacts on ecosystems and to prioritize conservation actions. [less ▲]

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