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See detailVoting on pensions with endogenous retirement age
Casamatta, G.; Cremer, H.; Pestieau, Pierre ULg

in International Tax and Public Finance (2005), 12(1), 7-28

It is often argued that the observed trend towards early retirement is due mainly to the implicit tax imposed on continued activity of elderly workers. We study the relevance of such a distortion in a ... [more ▼]

It is often argued that the observed trend towards early retirement is due mainly to the implicit tax imposed on continued activity of elderly workers. We study the relevance of such a distortion in a political economy model with endogenous age of retirement. The setting is a two-period overlapping generations model. Individuals differ in their productivity. In the first period they work a fixed amount of time; in the second, they choose when to retire and then receive a flat rate pension benefit. Pensions are financed by a payroll tax on earnings in the first and in the second period of life. Such a tax is non distortionary in the first period; it is distortionary in the second period. We allow for some rebating of the second period tax. Individuals vote on the level of the payroll tax given the rebate which can range from 0 (biased system) to 100% (neutral system). We provide sufficient conditions for the existence of a voting equilibrium and study its properties. Under these conditions, high tax rates are supported by all the old and by low productivity young individuals. We show that the pivotal voter is a young individual. The number of young individuals who have higher wage than the pivotal voter equals half the total population. We also show that the introduction of a bias increases the political support for the pension system. Finally, we study the simultaneous determination of the bias and the tax rate through a voting procedure and show that the equilibrium (if any) implies a bias which is always positive and may or not be larger than one. [less ▲]

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See detailPhosphorylation of NF-kappa B and I kappa B proteins: implications in cancer and inflammation
Viatour, Patrick ULg; Merville, Marie-Paule ULg; Bours, Vincent ULg et al

in Trends in Biochemical Sciences (2005), 30(1), 43-52

Nuclear factor-kappaB (NF-kappaB) is a transcription factor that has crucial roles in inflammation, immunity, cell proliferation and apoptosis. Activation of NF-kappaB mainly occurs via IkappaB kinase ... [more ▼]

Nuclear factor-kappaB (NF-kappaB) is a transcription factor that has crucial roles in inflammation, immunity, cell proliferation and apoptosis. Activation of NF-kappaB mainly occurs via IkappaB kinase (IKK)-mediated phosphorylation of inhibitory molecules, including IkappaBalpha. Optimal induction of NF-kappaB target genes also requires phosphorylation of NF-kappaB proteins, such as p65, within their transactivation domain by a variety of kinases in response to distinct stimuli. Whether, and how, phosphorylation modulates the function of other NF-kappaB and IkappaB proteins, such as B-cell lymphoma 3, remains unclear. The identification and characterization of all the kinases known to phosphorylate NF-kappaB and IkappaB proteins are described here. Because deregulation of NF-kappaB and IkappaB phosphorylations is a hallmark of chronic inflammatory diseases and cancer, newly designed drugs targeting these constitutively activated signalling pathways represent promising therapeutic tools. [less ▲]

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See detail[56,4(+)] baryons in the 1/N-c expansion
Matagne, Nicolas; Stancu, Floarea ULg

in Physical Review D (2005), 71(1),

Using the 1/N-c expansion of QCD, we analyze the spectrum of positive parity resonances with strangeness S=0, -1, -2, and -3 in the 2-3 GeV mass region, supposed to belong to the [56,4(+)] multiplet. The ... [more ▼]

Using the 1/N-c expansion of QCD, we analyze the spectrum of positive parity resonances with strangeness S=0, -1, -2, and -3 in the 2-3 GeV mass region, supposed to belong to the [56,4(+)] multiplet. The mass operator is similar to that of [56,2(+)], previously studied in the literature. The analysis of the latter is revisited. In the [56,4(+)] multiplet we find that the spin-spin term brings the dominant contribution and that the spin-orbit term is entirely negligible in the hyperfine interaction, in agreement with constituent quark model results. More data are strongly desirable, especially in the strange sector in order to fully exploit the power of this approach. [less ▲]

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See detailOptimal income taxation and the ability distribution: Implications for migration equilibria
Hamilton, J.; Pestieau, Pierre ULg

in International Tax and Public Finance (2005), 12(1), 29-45

As recently argued by Diamond (1998), one of the key factors explaining the progressivity of an optimal non-linear income tax is the distribution of productivity among workers. Migration is one source of ... [more ▼]

As recently argued by Diamond (1998), one of the key factors explaining the progressivity of an optimal non-linear income tax is the distribution of productivity among workers. Migration is one source of changes in the productivity distribution. How changes in the population's ability distribution affect optimal income tax schedules has received little attention. Changing the distribution generally affects both the objective function and the government budget constraint. We first consider the comparative statics of the fraction of highly-skilled workers with maximin and maximax welfare functions (so that only the second effect is present) and a quasi-linear utility function. We also present some results for a utilitarian social welfare function. We then study the interaction between mobility and redistributive taxation. We consider mobility by either the skilled or unskilled population under majority voting where governments take the population as fixed. If individuals choose to relocate independently, having identical ability distributions is always a stable equilibrium when the unskilled are the mobile group. However, this is not always the case when the skilled are mobile. If groups of individuals can choose where to locate, having identical ability distributions across regions is only an equilibrium when the mobile type has an overall majority. [less ▲]

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See detailUne évaluation de la mise en oeuvre du décret de promotion de la santé à l'école
Vandoorne, Chantal ULg; Grignard, Sophie ULg; Trefois, Patrick et al

in Education Santé (2005), (197), 11-14

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See detailShunting the intervillous space: New concepts in human uteroplacentat vascularization
Schaaps, Jean-Pierre ULg; Tsatsaris, Vassilis; Goffin, Frédéric ULg et al

in American Journal of Obstetrics and Gynecology (2005), 192(1), 323-332

Objective: It is supposed that the intervillous space. is not perfused by maternal blood during the first trimester, suggesting vascular shunts in the myometrium. We therefore attempted to provide ... [more ▼]

Objective: It is supposed that the intervillous space. is not perfused by maternal blood during the first trimester, suggesting vascular shunts in the myometrium. We therefore attempted to provide arguments for a functional vascular anastomotic network located in the placental bed during human pregnancy. Study design: Three-dimensional (3D) sonogyraphy, laboratory analyses. and anatomic studies (hysterectomy specimens, uteroplacental vascular cast) were performed. Results: Color Doppler showed a vascular network with anastomotic aspect located in the placental bed. A vascular cast of a uterus. obtained after postpartum hemorrhage. demonstrated a vascular anastomotic network in the myometrium. Higher Po-2 levels in the uterine vein compared with the intervillous space confirmed the functional nature of this Shunt. Low resistances in the uterine arteries during the first week after delivery suggested that this vascular network remains functional after placental expulsion. Conclusion: Our studies have yielded functional and anatomic evidence of an arteriovenous Shunt located in the subplacental myometrium. (C) 2005 Elsevier Inc. All rights reserved. [less ▲]

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See detailXylanases, xylanase families and extremophilic xylanases
Collins, T.; Gerday, Charles ULg; Feller, Georges ULg

in FEMS Microbiology Reviews (2005), 29(1), 3-23

Xylanases are hydrolytic enzymes which randomly cleave the beta 1,4 backbone of the complex plant cell wall polysaccharide xylan. Diverse forms of these enzymes exist, displaying varying folds, mechanisms ... [more ▼]

Xylanases are hydrolytic enzymes which randomly cleave the beta 1,4 backbone of the complex plant cell wall polysaccharide xylan. Diverse forms of these enzymes exist, displaying varying folds, mechanisms of action, substrate specificities, hydrolytic activities (yields, rates and products) and physicochemical characteristics. Research has mainly focused on only two of the xylanase containing glycoside hydrolase families, namely families 10 and 11, yet enzymes with xylanase activity belonging to families 5, 7, 8 and 43 have also been identified and studied, albeit to a lesser extent. Driven by industrial demands for enzymes that can operate under process conditions, a number of extremophilic xylanases have been isolated, in particular those from thermophiles, alkaliphiles and acidiphiles, while little attention has been paid to cold-adapted xylanases. Here, the diverse physicochemical and functional characteristics, as well as the folds and mechanisms of action of all six xylanase containing families will be discussed. The adaptation strategies of the extremophilic xylanases isolated to date and the potential industrial applications of these enzymes will also be presented. [less ▲]

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See detailPreparation and characterisation of poly(lactide-co-glycolide) (PLGA) and PLGA/Bioglass((R)) composite tubular foam scaffolds for tissue engineering applications
Boccaccini, Aldo R.; Blaker, Jonny J.; Maquet, Véronique et al

in Materials Science and Engineering C: Biomimetic and Supramolecular Systems (2005), 25(1), 23-31

Polylactide-co-glycolide (PLGA) and PLGA/Bioglass(R) foams of tubular shape have been prepared with a 1 wt% 45S5 Bioglass(R) content. Porous membranes with varying thickness and porosity were fabricated ... [more ▼]

Polylactide-co-glycolide (PLGA) and PLGA/Bioglass(R) foams of tubular shape have been prepared with a 1 wt% 45S5 Bioglass(R) content. Porous membranes with varying thickness and porosity were fabricated via a thermally induced phase separation process from which tubes of controlled diameter and wall thickness in the range 1.5-3 mm were produced. Scanning electron microscopy (SEM) revealed that the structure of the tubular foams consisted of radially oriented and highly interconnected pores with two distinct pore sizes, i.e. macropores similar to100-mum average diameter and interconnected micropores of 10-50-mum diameter. Foams with Bioglass(R) inclusions showed similarly well-defined tubular and interconnected pore morphology. Cell culture studies using mouse fibroblasts (L929) were conducted to assess the biocompatibility of the scaffolds in vitro. L929 fibroblasts cultured in medium that was pre-conditioned by incubating with PLGA tubes containing Bioglass(R) had a significant reduction in cell proliferation compared with fibroblasts grown in unconditioned medium (P < 0.0001). The PLGA and PLGA/Bioglass(R) tubular foams developed here are candidate materials for soft-tissue engineering scaffolds. holding promise for the regeneration of tissues requiring a tubular shape scaffold. such as intestine. trachea and blood vessels. [less ▲]

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See detailLe cas clinique du mois. Revascularisation des artères fémorales à partir de l'aorte thoracique descendante après thrombose d'un pontage axillo-bifémoral
Schleich, FLorence ULg; Van Damme, Hendrik ULg; Creemers, Etienne ULg et al

in Revue Médicale de Liège (2005), 60(1), 11-7

We report the case of a patient who had lower limb revascularization by a bypass graft originating from the decending thoracic aorta, after total thrombosis of an axillobifemoral bypass graft. The latter ... [more ▼]

We report the case of a patient who had lower limb revascularization by a bypass graft originating from the decending thoracic aorta, after total thrombosis of an axillobifemoral bypass graft. The latter had been performed for surgical repair of a secondary aorto-enteric fistula. We successively discuss the three particular apects of this observation: the secondary aortodigestive fistula, the axillobifemoral bypass and the bypass between the descending thoracic aorta and the femoral arteries. [less ▲]

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See detailMemory evaluation with a new cued recall test in patients with mild cognitive impairment and Alzheimer's disease
Ivanoiu, Adrian; Adam, Stéphane ULg; Van der Linden, Martial ULg et al

in Journal of Neurology (2005), 252(1), 47-55

Free delayed recall is considered the memory measure with the greatest sensitivity for the early diagnosis of dementia. However, its specificity for dementia could be lower, as deficits other than those ... [more ▼]

Free delayed recall is considered the memory measure with the greatest sensitivity for the early diagnosis of dementia. However, its specificity for dementia could be lower, as deficits other than those of pure memory might account for poor performance in this difficult and effortful task. Cued recall is supposed to allow a better distinction between poor memory due to concurrent factors and impairments related to the neurodegenerative process. The available cued recall tests suffer from a ceiling effect. This is a prospective, longitudinal study aiming to assess the utility of a new memory test based on cued recall that avoids the ceiling effect in the early diagnosis of Alzheimer's disease (AD). Twenty-five patients with mild cognitive impairment (MCI), 22 probable AD patients ( NINCDS-ADRDA) at a mild stage, 22 elderly patients with subjective memory complaints (SMC) and 38 normal age-matched controls took part in the study. The patients underwent a thorough cognitive evaluation and the recommended screening procedure for the diagnosis of dementia. All patients were re-examined 12 - 18 months later. A newly devised delayed cued recall test using semantic cues ( The RI48 Test) was compared with three established memory tests: the Ten Word-List Recall from CERAD, the "Doors" and the "Shapes" Tests from "The Doors and People Test Battery". Forty-four % of the MCI patients fulfilled criteria for probable AD at follow-up. The RI48 Test classified correctly 88% of the MCI and SMC participants and was the best predictor of the status of MCI and mild AD as well as the outcome of the MCI patients. Poor visual memory was the second best predictor of those MCI patients who evolved to AD. A cued recall test which avoids the ceiling effect is at least as good as the delayed free recall tests in the early detection of AD. [less ▲]

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See detailRevascularization of ischemic tissues by PDGF-CC via effects on endothelial cells and their progenitors
Li, X. R.; Tjwa, M.; Moons, L. et al

in Journal of Clinical Investigation (2005), 115(1), 118-127

The angiogenic mechanism and therapeutic potential of PDGF-CC, a recently discovered member of the VEGF/PDGF superfamily, remain incompletely characterized. Here we report that PDGF-CC mobilized ... [more ▼]

The angiogenic mechanism and therapeutic potential of PDGF-CC, a recently discovered member of the VEGF/PDGF superfamily, remain incompletely characterized. Here we report that PDGF-CC mobilized endothelial progenitor cells in ischemic conditions; induced differentiation of bone marrow cells into ECs; and stimulated migration of ECs. Furthermore, PDGF-CC induced the differentiation of bone marrow cells into smooth muscle cells and stimulated their growth during vessel sprouting. Moreover, delivery of PDGF-CC enhanced postischemic revascularization of the heart and limb. Modulating the activity of PDGF-CC may provide novel opportunities for treating ischemic diseases. [less ▲]

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See detailLa production écrite en langue étrangère et seconde
Defays, Jean-Marc ULg

in Français 2000 (2005), 194-195

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See detailAn XMM-Newton look at the Wolf-Rayet star WR 40 - The star itself, its nebula and its neighbours
Gosset, Eric ULg; Nazé, Yaël ULg; Claeskens, Jean-François ULg et al

in Astronomy and Astrophysics (2005), 429(2), 685-704

We present the results of an XMM-Newton observation of the field of the Wolf-Rayet star WR 40. Despite a nominal exposure of 20 ks and the high sensitivity of the satellite, the star itself is not ... [more ▼]

We present the results of an XMM-Newton observation of the field of the Wolf-Rayet star WR 40. Despite a nominal exposure of 20 ks and the high sensitivity of the satellite, the star itself is not detected: we thus derive an upper limit on its X-ray flux and luminosity. Joining this result to recent reports of a non-detection of some WC stars, we suggest that the X-ray emission from single normal Wolf-Rayet stars could often be insignificant despite remarkable instabilities in the wind. On the basis of a simple modelling of the opacity of the Wolf-Rayet wind of WR 40, we show that any X-ray emission generated in the particular zone where the shocks are supposed to be numerous will indeed have little chance to emerge from the dense wind of the Wolf-Rayet star. We also report the non-detection of the ejecta nebula RCW 58 surrounding WR 40. Concerning the field around these objects, we detected 33 X-ray sources, most of them previously unknown: we establish a catalog of these sources and cross-correlate it with catalogs of optical/infrared sources. [less ▲]

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See detailApplication of real-time voltage security assessment to the Hellenic Interconnected System
Van Cutsem, Thierry ULg; Kabouris, John; Christoforidis, George et al

in IEE Proceedings-Generation Transmission and Distribution (2005), 152(1), 123-131

The online voltage security assessment methods implemented at the national control centre of the Hellenic Interconnected System, within the framework of the OMASES project funded by the European Union are ... [more ▼]

The online voltage security assessment methods implemented at the national control centre of the Hellenic Interconnected System, within the framework of the OMASES project funded by the European Union are described. The heart of all computations is a fast time-domain method. Security is analysed with respect to power transfers in critical corridors or power consumption in load areas. Results take on the form of either precontingency secure operation limits, or postcontingency loadability limits, together with various diagnosis tips. Contingency filtering is performed to meet the real-time requirement. Typical results obtained during the test phase of the project are reported. [less ▲]

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See detailLaparoscopic sigmoidectomy for fistulized diverticulitis
Laurent, Stanislas; Detroz, Bernard ULg; Detry, Olivier ULg et al

in Diseases of the Colon & Rectum (2005), 48(1), 148-152

PURPOSE: Nowadays laparoscopic colorectal surgery has demonstrated its advantages, including reduced postoperative pain, decreased duration of ileus, and shorter hospital stay. Few studies report results ... [more ▼]

PURPOSE: Nowadays laparoscopic colorectal surgery has demonstrated its advantages, including reduced postoperative pain, decreased duration of ileus, and shorter hospital stay. Few studies report results of laparoscopic surgery in complicated diverticulitis. This study was designed to analyze the results of laparoscopic sigmoidectomy in patients with fistulized sigmoiditis. METHODS: The authors retrospectively reviewed 16 patients who had laparoscopic sigmoidectomy for fistulized diverticulitis between 1992 and 2003 in a series of 247 laparoscopic colectomies. Eleven patients presented with colovesical, four with colovaginal, and one with colocutaneous fistulas; all were caused by sigmoiditis. The procedure always consisted of celioscopic sigmoidectomy with stapled transanal suture and, when indicated, closure of the cystic or vaginal fistula orifice. RESULTS: Mean age was 60 (range, 39-78) years. Mean number of episodes of diverticulitis before operation was three (range, 1-5). Mean time between the last episode and operation was 46 (range, 2-250) weeks. In our first three years of experience, three cases (18.7 percent) were converted to laparotomy. Reasons for conversion were the necessity for intestinal resection, splenectomy, and a wound of the anterior rectum. The mean operative time was 172 (range, 100-280) minutes. Mean hospital stay was 5.7 (range, 3-12) days. There was no mortality. Postoperative morbidity (2 patients, 12.5 percent) consisted of one pulmonary infection and one splenectomy. Long-term follow-up revealed no recurrence of diverticulitis and one incisional hernia. CONCLUSIONS: In experienced hands, laparoscopic sigmoidectomy may be a safe and effective procedure for fistulized sigmoiditis. [less ▲]

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See detailMassive renal and adrenal calcifications in a young dialysis patient with familial Mediterranean fever
Delanaye, Pierre ULg; Krzesinski, Jean-Marie ULg

in Nephrology Dialysis Transplantation (2005), 20(1), 238-238

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See detailOn the multiplicity of the O-star Cyg OB2#8a and its contribution to the gamma-ray source 3EG J2033+4118
De Becker, Michaël ULg; Rauw, Grégor ULg; Swings, Jean-Pierre ULg

in Astrophysics & Space Science (2005), 297(1-4), 291-298

We present the results of an intensive spectroscopic campaign in the optical waveband revealing that Cyg OB2 # 8A is an O6+ O5.5 binary system with a period of about 21.9 days. Cyg OB2 # 8A is a bright X ... [more ▼]

We present the results of an intensive spectroscopic campaign in the optical waveband revealing that Cyg OB2 # 8A is an O6+ O5.5 binary system with a period of about 21.9 days. Cyg OB2 # 8A is a bright X-ray source, as well as a non-thermal radio emitter. We discuss the binarity of this star in the framework of a campaign devoted to the study of non-thermal emitters, from the radio waveband to gamma-rays. In this context, we attribute the non-thermal radio emission from this star to a population of relativistic electrons, accelerated by the shock of the wind-wind collision. These relativistic electrons could also be responsible for a putative gamma-ray emission through inverse Compton scattering of photospheric UV photons, thus contributing to the yet unidentified EGRET source 3EG J2033+ 4118. [less ▲]

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See detailOntogenesis and functional aspects of oxytocin and vasopressin gene expression in the thymus network
Hansenne, Isabelle ULg; Rasier, G.; Pequeux, Christel ULg et al

in Journal of Neuroimmunology (2005), 158(1-2), 67-75

Ontogenesis of oxytocin (OT) and vasopressin (VP) gene expression and function were investigated in murine thymus. OT and VP transcripts were detected in the thymus on embryonic days 13 and 15 ... [more ▼]

Ontogenesis of oxytocin (OT) and vasopressin (VP) gene expression and function were investigated in murine thymus. OT and VP transcripts were detected in the thymus on embryonic days 13 and 15, respectively. Corresponding messenger RNAs were evidenced in thymic epithelial cells by in situ hybridization with a neurophysin probe. From all OT and VP receptors, only OTR was expressed by all T-cell subsets, while V1bR was found in double positive and single positive CD8 cells. In fetal thymic organ cultures, OTR antagonist d[DTyr(Et)(2), Thr(4)]OVT increased early apoptosis of CD8 cells, while V1bR antagonist (Sanofi SSR 149415) inhibited T-cell differentiation, and favored CD8 T-cell commitment. (C) 2004 Elsevier B.V. All rights reserved. [less ▲]

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See detailL'addition est-elle infiniment associative ?
Dupont, Pascal ULg

in Mathématique et Pédagogie (2005), 150

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