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See detailControl of nuclear sample polarization using optical pumping and radio-frequency methods
Lenaers, Florence ULg; Glover, Rohan ULg; Bastin, Thierry ULg

Conference (2015, May 27)

Laser-cooled and trapped radioactive isotopes are now being used to probe the properties of the weak interaction in nuclear beta decay. In this context, it is essential that one be able to control the ... [more ▼]

Laser-cooled and trapped radioactive isotopes are now being used to probe the properties of the weak interaction in nuclear beta decay. In this context, it is essential that one be able to control the nuclear polarization of the atomic samples. We present two polarization/depolarization schemes for argon-35, whose mirror transition to chlorine-35 is a particularly sensitive candidate for precision measurements in nuclear beta decay. [less ▲]

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See detailControl of ordered mesoporous molecular sieves synthesis using non-ionic surfactants by incorporation of transition metal ions in the micellar solution
Léonard, Alexandre ULg; Blin, Jean-Luc; Herrier, Gontran et al

in Studies in Surface Science and Catalysis (2003), 146

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See detailControl of perimenstrual flares of perioral dermatitis by isotretinoin
Nikkels, Arjen ULg; Pierard, Gérald ULg

in Journal of Dermatological Treatment (2000), 11

BACKGROUNDS: Some cases of perioral dermatitis (POD) appear in young women after the interruption of oral contraception. Perimenstrual POD flares may also occur. Blue-brown, post-inflammatory macules and ... [more ▼]

BACKGROUNDS: Some cases of perioral dermatitis (POD) appear in young women after the interruption of oral contraception. Perimenstrual POD flares may also occur. Blue-brown, post-inflammatory macules and atrophic scarring often persist. Conventional treatment modalities include topical and oral tetracyclines, topical metronidazole and oral contraceptives. However, such therapies mau fail or offer only transient results. Isotretinoin efficacy was reported in a patient with difficult-to-treat POD. METHODS: We studied the outcome of a 6-month course of isotretinoin with a 1-year follow-up in 14 women suffering from chronic or recurrent POD refractory to or dependent on long-term conventional treatments. The isotretinoin dosing regiments were based on acne management guidelines. RESULTS: At 1-year follow-up, 12 of 14 (85,7 %) of the women remained free of POD recurrences, one patient (7,1 %) experienced a significant improvement, and one patient (7,1 %) showed only transient improvement during therapy, and rapidly relapsed after completing two 6-month treatment courses. The muco-cutaneous side effects were similar to those already known for isotretinoin. No other adverse effects occured. CONCLUSION: Isotretinoin represents a valuable therapeutic alternative for women suffering from chronic or recurrent POD refractory to or dependent on conventional treatment options. [less ▲]

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See detailControl of phase shifting transformers by multiple transmission system operators
Marinakis, Adamantios ULg; Glavic, Mevludin; Van Cutsem, Thierry ULg

(2007, July)

A general framework is proposed for the control of phase shifting transformers owned by several TSOs, taking into account their interactions. The proposed solution is the Nash equilibrium of a sequence of ... [more ▼]

A general framework is proposed for the control of phase shifting transformers owned by several TSOs, taking into account their interactions. The proposed solution is the Nash equilibrium of a sequence of optimizations performed by the various TSOs, each of them taking into account the other TSOs’ control settings as well as operating constraints relative to the whole system. The method is applied to a linearized network model and illustrated on the IEEE 118-bus system. [less ▲]

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See detailControl of phytoplankton bloom by winter conditions in a Mediterranean coastal area : results from a long–term study (1979–2011)
Goffart, Anne ULg; Hecq, Jean-Henri ULg; Legendre, Louis

Poster (2014, February)

The occurrence of a late-winter (February-March) phytoplankton bloom is one of the most unifying features of Mediterranean pelagic ecosystems. However, very little is known about the mechanisms that ... [more ▼]

The occurrence of a late-winter (February-March) phytoplankton bloom is one of the most unifying features of Mediterranean pelagic ecosystems. However, very little is known about the mechanisms that regulate the interannual variability of this phytoplankton bloom in coastal areas. In the present study, we show how winter physical forcing and environmental drivers control surface phytoplankton bloom dynamics in terms of the onset of the bloom, its duration, and its intensity through the analysis of a long-term time series (1979-2011) at the oligotrophic PhytoCly station (Bay of Calvi, Corsica, northwestern Mediterranean). We define a winter intensity index (WII) that integrates wind forcing and water temperature, and discuss strong correlations between WII and both surface nutrient fertilization and phytoplankton bloom intensity. Our study is consistent with reports that phytoplankton blooms can develop in homogenous water columns, and it does not fit the conventional idea that phytoplankton are blooming in temperate oceans because of warming/stratification of the surface layer. [less ▲]

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See detailControl of phytoplankton development by nitrate availability in the Liguro-Provençal basin (western Mediterranean)
Goffart, Anne ULg; Hecq, Jean-Henri ULg

in Progress in Belgian Oceanography Research, Royal Academy of Belgium, National Committee of Oceanology (1993)

Ten years of mesoscale oceanographic studies in the Liguro-Provençal basin (Corsican area) have emphasized that phytoplankton communities distribution is characterized by a high spatial and temporal ... [more ▼]

Ten years of mesoscale oceanographic studies in the Liguro-Provençal basin (Corsican area) have emphasized that phytoplankton communities distribution is characterized by a high spatial and temporal heterogeneity. The phytoplankton organization is greatly influenced by the presence of the Liguro-Provençal front whose functioning contributes significantly to increase the local productivity. The role of the front in the phytoplankton productivity enhancement is important all through the year but is much more effective from March to May. In the entire basin, a crucial moment for phytoplankton communities is encountered during summer, when surface waters are nutrient exhausted. The characteristic response of the primary producers is to sink below the surface mixed layer and to develop deep chlorophyll maxima (DCM). Their formation and maintenance are discussed. During the stratified period, all data support the view that phytoplankton distribution is primarily controlled by nitrate availability. [less ▲]

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See detailControl of plankton dynamics and fish recruitment by climate variation : example of Corsica, a Mediterranean island
Goffart, Anne ULg; Hecq, Jean-Henri ULg

Conference (2011, December)

In coastal areas of temperate and tropical small islands, most exploited fish species have undergone large reductions in stock size over the last decades. This impact is believed to be due, in large ... [more ▼]

In coastal areas of temperate and tropical small islands, most exploited fish species have undergone large reductions in stock size over the last decades. This impact is believed to be due, in large measure, to overfishing. However, in some cases, the poor recruitment of young fish or crustaceans of commercial interest is related to climate change. Here we present results acquired from three decades in Corsica, a small Mediterranean island where water quality is unbiased by terrestrial inputs and local activities. We show how plankton dynamics and fish recruitment are controlled by climate variation. Long-term changes of surface plankton dynamics are studied from 1979 at a permanent station in the oligotrophic Bay of Calvi (Corsica, Mediterranean Sea). As a distinctive feature of the area, the plankton bloom is characterized by a very large interannual variability reaching one order of magnitude from one year to another. Studies conducted to understand mechanisms controlling plankton variability emphasize a close relationship between climate variation (mainly winter wind stress intensity), water temperature and phytoplankton biomass. Shifts in phytoplankton community structure contribute to control the dynamics of zooplankton that rely on phytoplankton as food and influence the temporal succession of zooplankton assemblages. Changes in the timing, the biomass and the composition of the zooplankton communities result in a mismatch with the presence of the main food source of the small fish and alter recruitment success. The Corsican example could help to be aware of the potential consequences that changes in plankton dynamics controlled by climate variation will pose to coastal fishermen of small islands. [less ▲]

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See detailControl of plankton phenology by climate variation in a Mediterranean coastal area : results from a long-term study (1979-2011)
Goffart, Anne ULg; Collignon, Amandine ULg; Hecq, Jean-Henri ULg

Conference (2015, March)

Physical processes are known to play major roles in marine plankton succession. However, few studies have addressed the mechanisms that regulate phyto- and zooplankton phenology in a context of changing ... [more ▼]

Physical processes are known to play major roles in marine plankton succession. However, few studies have addressed the mechanisms that regulate phyto- and zooplankton phenology in a context of changing climate. Here we used a unique long-term (1979-2011) time series performed in a Mediterranean coastal area unbiased by local anthropogenic pressure (PHYTOCLY station, Bay of Calvi, Corsica) to understand how environmental forcing affects the timing, duration and magnitude of the winter-spring phyto- and zooplankton blooms. We showed that phyto- and zooplankton blooms were bottom-up controlled by the establishment of favourable abiotic conditions, i.e. nutrient replenishment by vertical mixing under specific water temperature and wind conditions, for which thresholds were defined. According to the intensity of winter characteristics, there were strong differences in both the abundance and composition of phyto- and zooplankton during the winter-spring period. Our study is consistent with the recent reports that, when occurring, diatoms peaks were added to the initial phytoplankton groups instead of replacing them. In contrast, zooplankton groups followed a replacement sequence. Based on the results provided by our time series, we show that plankton phenology in the Bay of Calvi is highly controlled by climate variation and exhibits contrasted patterns in response to different scenarios of environmental forcing. [less ▲]

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See detailControl of pneumonia in calves
Lekeux, Pierre ULg

(1999, October 22)

Respiratory disease is the principal cause of loss of young cattle worldwide. The syndrome arises from a number of factors, including Chose involving the animal, e.g., age, general condition and immune ... [more ▼]

Respiratory disease is the principal cause of loss of young cattle worldwide. The syndrome arises from a number of factors, including Chose involving the animal, e.g., age, general condition and immune statue; ifs environment, e.g., changes in food, temperature and humidity that lead to stress; and the presence of infections agents, e.g., bacteria, viruses and mycoplasmas. The syndrome, in a method preferred by the author, can be classified into four grades: Grade 1, subclinical disease;Grade 2, compensated clinical disease (at this stage, the inflammatriry reaction generated tends to lirait the impact of the disease on thi animal); Grade 3, noncompensated clinical disease (at this stage, the inflamniattxy reaction is excessive and must be controlled); and Grade 4, irrevertibk clinical disease (which threatens the animal's survival). The increase in frequency and economic impact of bovine respiratory disease complex can be correlated with the escalating industrialisation of cattle production. In intensive operations, commingling of animale from multiple sources, exposure to many organisme, stress and management practicgs are all factors that can lead to disease. - The predisposition of cattle, especially beef calves, to respiratory problems is related to their lack of functional pulmonary hardiness. Selection of breeds that demonstrate adequate pulmonary function and sufficient ventilatory reserve may help in the control of the bovine respiratory disease complex, but this approach is difficult to implement and slow to produce results. Prophylactic measures, including vaccination programmes and modifying management practices to reduce stress, also have a place in preventing the bovine respiratory disease complex. Unfortunately, these measures are not always easy to put into operation and cannot completely eradicate the problem. Therapeutic strategies to minimise the economic impact of the syndrome include use of appropriate antibacterial therapy, modulation of the pulmonary inflammatory reaction and correction of mechanical disorders. [less ▲]

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See detailControl of Polymyxa betae by Bacillus amyloliquefaciens lipopeptides
Desoignies, N.; Schramme, F.; Ongena, Marc ULg et al

Poster (2011)

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See detailThe control of postharvest blue and green molds of citrus in relation with essential oil-wax formulations, adherence and viscosity.
Kouassi, Kouadio Hugues Sosthène ULg; Bajji, Mohammed; Jijakli, Haissam ULg

in Postharvest Biology & Technology (2012), 73

The use of wax coatings enriched with antifungals has significantly contributed to quality maintaining of harvested citrus fruit. On the other hand, interest in essential oils (EOs) as an alternative to ... [more ▼]

The use of wax coatings enriched with antifungals has significantly contributed to quality maintaining of harvested citrus fruit. On the other hand, interest in essential oils (EOs) as an alternative to synthetic fungicides has recently gained momentum. In this study, Cinnamomum zeylanicum EO was incorporated into a variety of commercial citrus waxes (shellac, carnauba, paraffin and polyethylene). The biological activity of these formulations against green and blue rots as well as their viscosity and adherence to the orange fruit surface were evaluated. Excellent disease control was achieved with C. zeylanicum EO incorporated in shellac and/or carnauba wax compared to other EO–wax formulations. Disease control by EO–waxes seems to depend not only on the volume that remains on the fruit skin, but also, probably on the retention of EO components on the fruit. Other factors such as formulation solubility, permeability to gases, and compatibility between EO compounds and those of waxes may also be involved in the improvement of EO efficacy. The present study may therefore allow a careful selection of ppropriate waxes for the elaboration of effective EO–wax formulations. [less ▲]

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See detailThe control of preoptic aromatase activity by afferent inputs in Japanese quail
Absil, Philippe ULg; Baillien, M.; Ball, G. F. et al

in Brain Research Reviews (2001), 37(1-mars Sp. Iss. SI), 38-58

This review summarizes current knowledge on the mechanisms that control aromatase activity in the quail preoptic area, a brain region that plays a key role in the control of reproduction. Aromatase and ... [more ▼]

This review summarizes current knowledge on the mechanisms that control aromatase activity in the quail preoptic area, a brain region that plays a key role in the control of reproduction. Aromatase and aromatase mRNA synthesis in the preoptic area are enhanced by testosterone and its metabolite estradiol, but estradiol receptors of the alpha subtype are not regularly colocalized with aromatase. Estradiol receptors of the beta subtype are present in the preoptic area but it is not yet known whether these receptors are colocalized with aromatase. The regulation by estrogen of aromatase activity may be, in part, trans-synaptically mediated, in a manner that is reminiscent of the ways in which steroids control the activity of gonadotropic hormone releasing hormone neurons, Aromatase-immunoreactive neurons are surrounded by dense networks of vasotocin-immunoreactive and tyrosine hydroxylase-immunoreactive fibers and punctate structures. These inputs are in part steroid-sensitive and could therefore mediate the effects of steroids on aromatase activity. In vivo pharmacological experiments indicate that catecholaminergic depletions significantly affect aromatase activity presumably by modulating aromatase transcription. In addition, in vitro studies on brain homogenates or on preoptic-hypothalamic explants show that aromatase activity can be rapidly modulated by a variety of dopaminergic compounds. These effects do not appear to be mediated by the membrane dopamine receptors and could involve changes in the phosphorylation state of the enzyme, Together, these results provide converging evidence for a direct control of aromatase activity by catecholamines consistent with the anatomical data indicating the presence of a catecholaminergic innervation of aromatase cells. These dopamine-induced changes in aromatase activity are observed after several hours or days and presumably result from changes in aromatase transcription but rapid non-genomic controls have also been identified. The potential significance of these processes for the physiology of reproduction is critically evaluated. (C) 2001 Elsevier Science BY. All rights reserved. [less ▲]

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See detailControl of proliferation and differentiation in B16 melanoma cells in bi- or tridimensional cultures
Bassleer, Roger; De Pauw-Gillet, Marie-Claire ULg; Simonon, Anne et al

Poster (1985, May)

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See detailControl of proliferation, endoreduplication and differentiation by the Arabidopsis E2Fa-DPa transcription factor
De Veylder, L.; Beeckman, T.; Beemster, G. T. S. et al

in EMBO Journal (2002), 21(6), 1360-1368

New plant cells arise at the meristems, where they divide a few times before they leave the cell-cycle program and start to differentiate. Here we show that the E2Fa-DPa transcription factor of ... [more ▼]

New plant cells arise at the meristems, where they divide a few times before they leave the cell-cycle program and start to differentiate. Here we show that the E2Fa-DPa transcription factor of Arabidopsis thaliana is a key regulator determining the proliferative status of plant cells. Ectopic expression of E2Fa induced sustained cell proliferation in normally differentiated cotyledon and hypocotyl cells. The phenotype was enhanced strongly by the co-expression of E2Fa with its dimerization partner, DPa. In endoreduplicating cells, E2Fa-DPa also caused extra DNA replication that was correlated with transcriptional induction of S phase genes. Because E2Fa-DPa transgenic plants arrested early in development, we argue that controlled exit of the cell cycle is a prerequisite for normal plant development. [less ▲]

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See detailControl of puberty by excitatory amino acid neurotransmitters and its clinical implications
Parent, Anne-Simone ULg; Matagne, V.; Bourguignon, Jean-Pierre ULg

in Endocrine (2005), 28(3), 281-285

Excitatory amino acids, glutamate in particular, have a marked stimulatory effect on the reproductive axis, particulary at puberty. Glutamate, N-methyl-D-aspartate (NMDA), and kainate stimulate ... [more ▼]

Excitatory amino acids, glutamate in particular, have a marked stimulatory effect on the reproductive axis, particulary at puberty. Glutamate, N-methyl-D-aspartate (NMDA), and kainate stimulate gonadotropin-releasing hormone (GnRH) secretion in immature mammals and NMDA receptor stimulation results in precocious puberty in rats and monkeys. Puberty is characterized by an increased sensitivity of GnRH to glutamate as well as an increase in glutaminase activity in the hypothalamus. Glutamatergic and GABAergic regulation of GnRH secretion seem strongly interdependent around puberty. in addition to the transsynaptic glutamatergic regulation of GnRH secretion, a coordinated activity of glutamatergic neurons and astroglial cells has been shown to play an active role in puberty. The participation of kainate receptors in the estradiol-induced advancement of puberty suggest that these receptors may be involved in the estradiol-mediated activation of GnRH secretion at puberty. A case of precocious puberty associated with hyperglycinemia illustrates the NMDA involvement in puberty in humans. in this patient, the occurrence of precocious puberty was thought to result from excessive stimulation by glycine of the NMDA receptors linked to the GnRH neurons. Glutamate plays several roles in the hypothalamic mechanism of puberty as it has been shown in animal models, but there are still few clinical data supporting the role of glutamate in human puberty. [less ▲]

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See detailControl of Pulsatile Secretion of Gonadotrophin Releasing Hormone from Hypothalamic Explants
Bourguignon, Jean-Pierre ULg; Gerard, Arlette ULg; Alvarez Gonzalez, Maria-Luz ULg et al

in Human Reproduction (1993), 8 Suppl 2(NULL), 18-22

We have studied the secretion of gonadotrophin releasing hormone (GnRH) from hypothalamic explants of male rats at different ages in an attempt to delineate the neuroendocrine mechanism of the onset of ... [more ▼]

We have studied the secretion of gonadotrophin releasing hormone (GnRH) from hypothalamic explants of male rats at different ages in an attempt to delineate the neuroendocrine mechanism of the onset of puberty. In this paper, we review some of our recent studies and we provide evidence of a dual control played by receptors to neuroexcitatory amino acids. We showed previously that isolated explants of rat hypothalamus could secrete GnRH in a pulsatile manner. The onset of puberty was characterized by a 2-fold increase in frequency of GnRH secretory pulses. This reduction of the interval between GnRH pulses involved an inhibitory autofeedback effect of GnRH on the pulse generator which was shut off following a secretory episode. This period of refractoriness was longer before puberty than after the onset of puberty. Activation of receptors to neuroexcitatory amino acids (N-methyl-D-aspartate; NMDA-type) was involved in the mechanism of pulsatile GnRH secretion. Striking developmental changes in NMDA-receptor-mediated GnRH secretion were demonstrated with a maximal activity around the time of the onset of puberty. Similar changes occurred in orchidectomized animals, indicating that this maturational process was gonad-independent. While evidence accumulated that NMDA receptors were involved in a stimulatory control of GnRH secretion, we found that NMDA receptors mediated an inhibitory effect on GnRH secretion. This inhibitory effect was very potent in the immature hypothalamus and it showed a marked reduction in potency before onset of puberty.(ABSTRACT TRUNCATED AT 250 WORDS) [less ▲]

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See detailControl of radical reactions by bimetallic systems
Richel, Aurore ULg

Conference (2002)

The original application of ruthenium-titanium bimetallic systems either in ATRP or in Kharasch addition (ATRA) is presented

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See detailControl of radical reactions by transition-metal complexes
Richel, Aurore ULg

Doctoral thesis (2007)

The overall goal of this Ph.D. is to contribute to the conception, the synthesis and the characterisation of original homogeneous ruthenium-based catalytic systems (or heterobimetallic ruthenium-titanium ... [more ▼]

The overall goal of this Ph.D. is to contribute to the conception, the synthesis and the characterisation of original homogeneous ruthenium-based catalytic systems (or heterobimetallic ruthenium-titanium systems), highly active and effective towards atom transfer radical addition (ATRA) and polymerisation (ATRP) of several representative vinyl monomers. As catalytic performances may be tuned by the nature and the structure of the ligands around the metallic core, we are intending to systematically elucidate (by NMR and electrochemistry) the relations between stereoelectronic ligands parameters and the catalytic activity. Microwave irradition is also considered as an unexpected heating source for performing radical reactions. [less ▲]

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See detailControl of radical reactions mediated by bimetallic systems
Richel, Aurore ULg; Delfosse, Sébastien; Demonceau, Albert ULg et al

Poster (2001)

We present herein preliminary results on the use of Ti-Ru bimetallic catalyst systems in Kharasch chemistry and atom transfer radical polymerisation

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See detailControl of Salmonella contamination of shell eggs – preharvest and postharvest methods: a review
Galis, Anca; Marcq, Christopher ULg; Marlier, Didier ULg et al

in Comprehensive Reviews in Food Science and Food Safety (2013), 12

Salmonella Enteritidis is one of the most prevalence foodborne pathogen, its most important reservoir being considered the shell egg. As the concerns related to the increasing human salmonellosis cases ... [more ▼]

Salmonella Enteritidis is one of the most prevalence foodborne pathogen, its most important reservoir being considered the shell egg. As the concerns related to the increasing human salmonellosis cases grow, the need for an application of preventive methods either at the farm level or during the processing steps is crucial for a better control of the foodborne outbreaks due to the consumption of this specific food product. This review focuses on the application of preventive methods at the farm level, on preharvest step, in order to reduce the risk of shell eggs contamination with Salmonella, especially S. Enteritidis, through a better control of the laying hens’ infection with this pathogen. As postharvest methods, a first approach is the egg storage conditions and the prevention of Salmonella spp. growth and multiplication. In addition, shell eggs may be subjected to eggshell decontamination, to reduce the risk of foodborne outbreaks. Several of these latter mentioned methods are already authorized to be put in place in different countries, as it is the case in the United States of America and Canada. Their efficacy has been proven and their use is regarded by some as mandatory for ensuring shell eggs safety for the consumers. [less ▲]

Detailed reference viewed: 96 (22 ULg)