Browsing
     by title


0-9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

or enter first few letters:   
OK
See detailFrom myopic coordination to resilience in socio-technical systems. A case study in a hospital
Nyssen, Anne-Sophie ULg

in Hollnagel, Erik; Paries, Jean; Woods, David (Eds.) et al Resilience Engineering in Practice: A guidebook (2011)

Detailed reference viewed: 87 (36 ULg)
Full Text
See detailFrom nets to bottom traps: is exploitation of Norway lobsters a suitable option for Corsican common spiny lobster fishermen?
Patrissi, Michela; Astrou, Adèle; Pelaprat, Corinne et al

Poster (2014, May 20)

In Corsica (NW Mediterranean), most of the fishing activity is composed of small-scale artisanal fisheries, and takes place on the western coast. The common spiny lobster (Palinurus elephas) is the main ... [more ▼]

In Corsica (NW Mediterranean), most of the fishing activity is composed of small-scale artisanal fisheries, and takes place on the western coast. The common spiny lobster (Palinurus elephas) is the main target of Corsican netters. However, its populations have been declining since the 1950's, questioning the sustainability of this activity. We therefore tried to assess whether the fishing effort, currently mostly focused on common spiny lobsters, could be moved towards other commercially-interesting deep crustaceans, such as the Norway lobster (Nephrops norvegicus), through diversification of artisanal fishing practices. With the help of local fishermen, we set up Scottish traps for Norway lobsters at depths of 300 to 400 meters, on sandy and muddy bottoms of both eastern and western coasts. Despite several tests using different baits and soak times at various depths or seasons, catches on the western coast were low. On the other hand, on the eastern coast, experimentation showed interesting yields, and large mean size (i.e. high commercial value) for both sexes. While more studies are needed to confirm these results and improve knowledge of Norway lobster stocks, trap fishing of this species on eastern coast of Corsica could be a suitable alternative for diversification of artisanal fisheries. [less ▲]

Detailed reference viewed: 32 (1 ULg)
Full Text
Peer Reviewed
See detailFrom Neural Stem Cells to Myelinating Oligodendrocytes
Rogister, Bernard ULg; Ben Hur, Tamir; Dubois-Dalcq, Monique

in Molecular & Cellular Neuroscience [=MCN] (1999), 14

Detailed reference viewed: 3 (0 ULg)
Peer Reviewed
See detailFrom neurophysiology to genetics: cortical information processing in migraine underlies familial influences--a novel approach
Sandor, P. S.; Afra, J.; Proietti Cecchini, A. P. et al

in Functional Neurology (2000), 15(Suppl 3), 68-72

Migraine patients show impaired cortical information processing between attacks with deficient habituation of pattern-reversal visual evoked potentials (VEP), and strong intensity dependence of auditory ... [more ▼]

Migraine patients show impaired cortical information processing between attacks with deficient habituation of pattern-reversal visual evoked potentials (VEP), and strong intensity dependence of auditory cortical evoked potentials (IDAP). This could be a genetic trait as certain genetic patterns are known for evoked potentials in healthy subjects. VEP-habituation and IDAP were studied in 40 migraine patients, i.e. pairs of 20 parents and their children. We developed a novel approach based on Monte Carlo statistics to selectively assess vertical familial influences. Both groups, parents and children, were characterized by abnormal VEP-habituation and IDAP. However, similarity between related pairs was far more pronounced than similarity between unrelated pairs. Assessed with a novel statistical approach, familial influences proved to be highly significant in determining cortical information processing in migraineurs, thus supporting the important role of genetic factors. [less ▲]

Detailed reference viewed: 26 (4 ULg)
Full Text
Peer Reviewed
See detailFrom Newton's Fluxions to Virtual Microscopes
Bair, Jacques ULg; Henry, Valérie ULg

in Teaching Mathematics and Computer Science (2007), 5(2), 377-384

The method of fluxions was originally given by Newton in order to determine the tangent to a curve. In this note, we will formulate this method by the light of some modern mathematica tools.

Detailed reference viewed: 25 (0 ULg)
Full Text
Peer Reviewed
See detailFrom Nollywood to Nollyworld: Processes of transnationalization in the Nigerian video film industry
Jedlowski, Alessandro ULg

in Krings, Matthias (Ed.) Global Nollywood: Transnational Dimensions of an African Video Film Industry (2013)

Detailed reference viewed: 20 (1 ULg)
Peer Reviewed
See detailFrom Non-invasive Site Characterization to Site Amplification: Recent Advances in the Use of Ambient Vibration Measurements.
Bard, P-Y; et al.; Havenith, Hans-Balder ULg

in Geotechnical, Geological and Earthquake Engineering : Earthquake Engineering in Europe (2010)

Detailed reference viewed: 16 (0 ULg)
Full Text
Peer Reviewed
See detailFrom Normal Business to Financial Crisis... and Back Again. An Illustration of the Benefits of Cassandre for Qualitative Analysis
Lejeune, Christophe ULg

in Forum: Qualitative Sozialforschung = Forum: Qualitative Social Research [FQS] (2011), 12(1), 19

Cassandre is a free open source text analysis software tool. It uses semi-automatic coding, based on the identification of markers, grouped into registers, which represent analysis categories. Studying ... [more ▼]

Cassandre is a free open source text analysis software tool. It uses semi-automatic coding, based on the identification of markers, grouped into registers, which represent analysis categories. Studying the causes of the financial crisis makes it possible to construct a series of registers (responsibility, negligence, domino effect, change and return to normal). Cross-referencing these registers reveals contrasting views (positive and negative) of the economic, political and financial spheres. These conceptions vary both according to how they explain the phenomenon and the measures that they advocate (ranging from the development of new methods to "getting back to normal"). The example of the financial crisis is an opportunity to discuss the benefits of semi-automatic coding and determine the limitations that are likely to impact negatively on the analysis. [less ▲]

Detailed reference viewed: 771 (41 ULg)
Peer Reviewed
See detailFrom obesity to diabetes: why, when and who?
Scheen, André ULg

in Acta Clinica Belgica (2000), 55(1), 9-15

Obesity is considered as the most important risk factor for type 2 diabetes. We will briefly discuss why does obesity predispose to diabetes, when does diabetes occur in obese subjects and who among obese ... [more ▼]

Obesity is considered as the most important risk factor for type 2 diabetes. We will briefly discuss why does obesity predispose to diabetes, when does diabetes occur in obese subjects and who among obese individuals is particularly prone to develop diabetes. Obesity, especially intraabdominal adiposity, is associated with increased FFA plasma concentrations which exert a major negative effect on insulin sensitivity at both muscular and hepatic sites. Various metabolic, haemodynamic and hormonal theories have been proposed to explain insulin resistance in obese subjects. A specific role of TNF-alpha has been recently suggested. However, besides insulin resistance, defective insulin secretion is a prerequisie for the development of overt type 2 diabetes. Both lipotoxicity and glucotoxicity may initiate and perpetuate a vicious circle responsible for the metabolic deterioration. Diabetes occurs as a late phenomenon in obesity and is preceded by years of impaired glucose tolerance. The progression to diabetes is heralded by an inability of the B cell to maintain its previously high rate of insulin secretion in response to glucose in face of insulin resistance. This propensity to develop type 2 diabetes may be genetically determined and/or triggered by environmental factors. The evolution from obesity to diabetes represents a continuum that progresses through different phases in which defects in both insulin action and insulin secretion play a critical interaction and must be looked at in concert. [less ▲]

Detailed reference viewed: 25 (2 ULg)
Peer Reviewed
See detailFrom obesity to type 2 diabetes.
Scheen, André ULg

in Acta Clinica Belgica. Supplementum (1992), 14

Obesity is a well-known risk factor for the development of non-insulin-dependent diabetes mellitus (NIDDM). Both insulin resistance and concomitant B-cell dysfunction are necessary for the development of ... [more ▼]

Obesity is a well-known risk factor for the development of non-insulin-dependent diabetes mellitus (NIDDM). Both insulin resistance and concomitant B-cell dysfunction are necessary for the development of NIDDM. Insulin resistance, probably genetically determined but worsened by obesity, appears to be the primary defect that leads to impaired glucose tolerance. However, B-cell dysfunction plays a critical role during progressive deterioration from mild impaired glucose tolerance to severe NIDDM. [less ▲]

Detailed reference viewed: 16 (0 ULg)
See detailFrom One Loop To Another: From Minimalism To Indie Rock
Levaux, Christophe ULg

Conference (2013, October 05)

Detailed reference viewed: 24 (2 ULg)
Full Text
Peer Reviewed
See detailFrom oxides to selenides and sulfides: The richness of the CdI2 type crystallographic structure for thermoelectric properties
S, Hébert; W, Kobayashi; Y, Bréard et al

in Physica Status Solidi A. Applications and Materials Science (2013), 210(1), 69-81

In this paper, we show how the thermoelectric properties can be modified in crystallographic structures based on the CdI2 type layer, by changing the block layers between these CdI2 type layers or by ... [more ▼]

In this paper, we show how the thermoelectric properties can be modified in crystallographic structures based on the CdI2 type layer, by changing the block layers between these CdI2 type layers or by going from oxides to selenides and sulfides. In the case of oxides, the unique properties generated in these structures will be demonstrated in Bi-based misfit compounds. By combining Hall effect, resistivity, and Seebeck coefficients in single crystals of this family, the importance of doping and of spin and orbital degeneracy term on the Seebeck coefficient will be shown. From this single crystal investigation, the power factor at 300 K is found to be unexpectedly constant as a function of doping. To further enhance the power factor and thus ZT, it is necessary to modify either the block layer or to perform anionic substitutions. By going from oxides to selenides and sulfides, the decrease of the ionic character can induce a decrease of electrical resistivity. Compared to oxides, the properties can generally be described in a more classical way using Boltzmann transport theory. For these materials, the critical parameter is then thermal conductivity and this quantity can be decreased as shown here by intercalating Cu between the layers (CuxTiS2), or by making solid solution such as TiS2 − xSex. These two approaches will be described here, leading to ZT close to 0.5 and 0.4, at 800 and 700 K, respectively. [less ▲]

Detailed reference viewed: 4 (0 ULg)
Full Text
Peer Reviewed
See detailFrom palaeosols to carbonate mounds: facies and environments of the middle Frasnian platform in Belgium
Da Silva, Anne-Christine ULg; Boulvain, Frédéric ULg

in Geological Quarterly (2004), 48(3), 253-265

This paper provides a synthetic sedimentological overview of the middle Frasnian carbonate platform of Belgium and associated carbonate mounds. Carbonate mounds started usually in a relatively deep, quiet ... [more ▼]

This paper provides a synthetic sedimentological overview of the middle Frasnian carbonate platform of Belgium and associated carbonate mounds. Carbonate mounds started usually in a relatively deep, quiet subphotic environment with a crinoid-coral-sponge assemblage, then reached the fair-weather wave base and the euphotic zone with an algal-microbial facies. The upper parts of the mounds are characterised by lateral facies differentiation with the algal-microbial facies protecting a central sedimentation area with a dendroid stromatoporoids facies and fenestral limestone. The lateral facies reflect different kinds of input of reworked mound material in the proximal area, from transported fine-grained sediment to coarse-grained fossil debris. On the platform, environments range from the outer zone (crinoidal facies) to stromatoporoid-dominated biostromes and to the lagoonal area of the inner zones (subtidal facies with Amphipora floatstone, algal packstone, intertidal mudstone and laminated peloidal packstone and palacosols). These facies are stacked in metre-scale shallowing-upward cycles. The larger scale sequential organisation corresponds to transgressions and regressions, whose cycles are responsible for differentiating a lower open-marine biostrome dominated unit from an upper lagoonal unit. The last regression-transgression cycle, responsible for the platform-scale development of lagoonal facies, can be correlated with an atoll-stage evolution of the carbonate mounds belonging to the Lion Member. [less ▲]

Detailed reference viewed: 73 (11 ULg)
See detailFrom paradigm dynamics towards landscape ecology ontogenesis
Bogaert, Jan ULg

in Farina, A. (Ed.) Ecology, Cognition and Landscape: Linking Natural and Social Systems. Landscape series 11. (2009)

Detailed reference viewed: 11 (3 ULg)
Full Text
See detailFrom photons to biomass in green microalgae: fluorimetric and oxymetric studies on the regulation of photosynthetic electron transport
de Marchin, Thomas ULg

Doctoral thesis (2015)

Analyzing the photosynthetic performances of microalgae has become an important topic in view of the ecological importance of these microorganisms and of the growing field of their biotechnological ... [more ▼]

Analyzing the photosynthetic performances of microalgae has become an important topic in view of the ecological importance of these microorganisms and of the growing field of their biotechnological applications. In this thesis, we developed methods which allow effective use of fluorescence and oxygen experimental signals for a more complete analysis of the functioning of the photosynthetic apparatus of green microalgae under different conditions. We applied these methods to analyze the adaptations of the photosynthetic apparatus under selected conditions, especially regarding CO2 supply. In the first part of this work, we applied a fluorescence-based method for determining the PSII antenna size based on the kinetics of the fast chlorophyll a fluorescence transient in presence of DCMU (or DCMU Fluorescence Rise). We then performed a detailed analysis of the different phases of this transient which are associated with different types of PSII formerly described as PSIIalpha and PSIIbeta (PSII heterogeneity). Our results on PSII heterogeneity during a transition from state 2 to state 1 in Chlamydomonas reinhardtii showed for the first time in vivo that this transition correlates with a conversion of PSIIbeta to PSIIalpha. We also discuss the possible relationships between PSIIalpha and PSIIbeta and the PSII mega-, super- and core- complexes described by biochemical studies. In photoautotophic atmospheric conditions, microalgae often have to deal with limited CO2 availability. The unicellular green algae Chlamydomonas reinhardtii can adapt to low CO2 concentration with the inorganic carbon concentration mechanism (CCM). This has been extensively studied in the past. However, other functional adaptations of the photosynthetic apparatus to CO2 limitation have been much less studied. In the second part of this work, we used combined fluorescence-based electron transport and oxygen measurements to evaluate the responses to low and high CO2 in Chlamydomonas reinhardtii grown in photobioreactors at different light intensities. We developed a method to rationalize the relationship between the apparent quantum yields of oxygen evolution and of electron transport at PSII while taking into account the variations in the proportion of energy absorbed by PSII. We used this relationship as a tool to evidence a significant O2-dependent alternative electron transport in low CO2 acclimated cells. We showed that this alternative electron transport can represent up to 60% of the total electron transport in low CO2 cells even upon removal of the CO2 limitation by bicarbonate addition. In contrast, no significant alternative electron transport was detected in high CO2 cells. We suggest that the alternative electron transport to O2 observed in low CO2 cells represents an adaptation that could help to meet the higher ATP demand for the concentration of CO2 by the CCM. In contrast, in high CO2 conditions, the absence of the CCM would reduce the need for ATP and thus the need for electron transport to O2. Using mutants and inhibitors, we studied the involvement of known O2-dependent electron sinks such as the mitochondrial cytochrome and alternative oxidase pathways and also of chlororespiration in this light-dependent O2 uptake and we found no evidence for the involvement of any of these processes. The alternative electron transport was even higher in a mitochondrial mutant devoid of complexes I and III and we suggest that this alternative electron transport could compensate for the absence of mitochondrial ATP synthesis in this mutant. By elimination, our results suggest that the alternative electron transport to O2 evidenced here could be driven by a Mehler-type reaction although we did not find direct evidences for increased Mehler-type activity in low CO2 cells. Additionally from fluorescence measurements performed directly in the cultures, we concluded that low CO2 cells had a lowest PSII photosynthetic efficiency and developed strong qE NPQ. Our results indicate that Chlamydomonas reinhardtii is capable to induce an ample thermal dissipation of excitation energy and the extent of this process is influenced essentially by the CO2 availability. In contrast with results obtained in previous studies, low temperature fluorescence spectra showed that in high light, high CO2 cells were characterised by a higher proportion of light energy absorbed by PSI compared to low CO2 cells. This was accompanied by a decrease of PSII antenna size as shown by DCMU-FR measurements. These findings are discussed in relation with the conflicting theories concerning the role of state transitions in the regulation of the cyclic electron transport around PSI. Our results support the idea that CEF is regulated by the redox state of the chloroplast rather than by state transitions. Over the last decades, microalgae have been increasingly studied because of their potential applications in industry. Despite a growing interest in microalgae mass cultures, the majority of studies on microalgae have been carried out at a laboratory scale and only few studies have addressed the question of photosynthetic adaptations in mass cultures. It is well known that CO2 addition increases the growth rate of microalgae and for this reason, some mass microalgae cultures are CO2 supplemented. Among the studies on microalgae mass culture, as far as we know, none directly compared high CO2 (CO2 supplemented air) and low CO2 (air) conditions. In the last part of our work, two outdoor open thin-layer cascade systems operated as batch cultures with the alga Scenedesmus obliquus were used to compare the productivity and photosynthetic adaptations in control and CO2 supplemented cultures in relation with the outdoor light irradiance. We found that the culture productivity was limited by CO2 availability beyond a threshold of daily irradiance. In the CO2 supplemented culture, we obtained a productivity of up to 25 g dw.m-2.day-1 and found a photosynthetic efficiency of 2.6%. Fluorescence and oxygen evolution measurements showed that ETR and oxygen evolution light saturation curves, as well as alternative electron transport were similar in algal samples from both cultures when the CO2 limitation was removed. In contrast, we found that CO2 limitation conducted to a decreased PSII photochemical efficiency and an increased light-induced heat-dissipation in the control culture compared to the CO2 supplemented culture. These features may contribute to the lower productivity observed in absence of CO2 supplementation in outdoor mass cultures of Scenedesmus obliquus. [less ▲]

Detailed reference viewed: 42 (15 ULg)