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See detailHetero Diels-Alder (HDA) reactions of 1-phosphono-1,3-butadienes with azo and nitroso dienophiles : an entry towards versatile heterocyclic synthons for aminophosphonic compounds
Monbaliu, Jean-Christophe ULg; Villemin, Elise; Elias, Benjamin et al

in Attanasi, Orazio (Ed.) Targets in heterocyclic systems - Chemistry and Properties (2010)

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See detailHétéro-régulation, auto-régulation et co-régulation: esquisse théorique et application au marché des services de médias audiovisuels
Thirion, Nicolas ULg

in Jongen, François (Ed.) La directive services de médias audiovisuels - Le nouveau cadre juridique de l'audiovisuel européen (2010)

Dans une perspective de droit français et de droit européen, application au marché de services de médias audiovisuels des trois modèles possibles de régulation d'une activité économique: hétéro-, auto- et ... [more ▼]

Dans une perspective de droit français et de droit européen, application au marché de services de médias audiovisuels des trois modèles possibles de régulation d'une activité économique: hétéro-, auto- et co-régulation. [less ▲]

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See detailHeterochronicity of white matter development and aging explains regional patient control differences in schizophrenia.
Kochunov, Peter; Ganjgahi, Habib; Winkler, Anderson ULg et al

in Human Brain Mapping (2016), 37(12), 4673-4688

BACKGROUND: Altered brain connectivity is implicated in the development and clinical burden of schizophrenia. Relative to matched controls, schizophrenia patients show (1) a global and regional reduction ... [more ▼]

BACKGROUND: Altered brain connectivity is implicated in the development and clinical burden of schizophrenia. Relative to matched controls, schizophrenia patients show (1) a global and regional reduction in the integrity of the brain's white matter (WM), assessed using diffusion tensor imaging (DTI) fractional anisotropy (FA), and (2) accelerated age-related decline in FA values. In the largest mega-analysis to date, we tested if differences in the trajectories of WM tract development influenced patient-control differences in FA. We also assessed if specific tracts showed exacerbated decline with aging. METHODS: Three cohorts of schizophrenia patients (total n = 177) and controls (total n = 249; age = 18-61 years) were ascertained with three 3T Siemens MRI scanners. Whole-brain and regional FA values were extracted using ENIGMA-DTI protocols. Statistics were evaluated using mega- and meta-analyses to detect effects of diagnosis and age-by-diagnosis interactions. RESULTS: In mega-analysis of whole-brain averaged FA, schizophrenia patients had lower FA (P = 10-11 ) and faster age-related decline in FA (P = 0.02) compared with controls. Tract-specific heterochronicity measures, that is, abnormal rates of adolescent maturation and aging explained approximately 50% of the regional variance effects of diagnosis and age-by-diagnosis interaction in patients. Interactive, three-dimensional visualization of the results is available at www.enigma-viewer.org. CONCLUSION: WM tracts that mature later in life appeared more sensitive to the pathophysiology of schizophrenia and were more susceptible to faster age-related decline in FA values. Hum Brain Mapp 37:4673-4688, 2016. (c) 2016 Wiley Periodicals, Inc. [less ▲]

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See detailHeterochrony in a complex world: disentangling environmental processes of facultative paedomorphosis in an amphibian
Denoël, Mathieu ULg; Ficetola, Gentile Francesco

in Journal of Animal Ecology (2014), 83(3), 606-615

1. Heterochrony, the change in the rate or timing of development between ancestors and their descendants, plays a major role in evolution. When heterochrony produces polymorphisms, it offers the ... [more ▼]

1. Heterochrony, the change in the rate or timing of development between ancestors and their descendants, plays a major role in evolution. When heterochrony produces polymorphisms, it offers the possibility to test hypotheses that could explain its success across environments. Amphibians are particularly suitable to exploring these questions because they express complex life cycles (i.e. metamorphosis) that have been disrupted by heterochronic processes (paedomorphosis: retention of larval traits in adults). The large phenotypic variation across populations suggests that more complex processes than expected are operating, but they remain to be investigated through multivariate analyses over a large range of natural populations across time. 2. In this study we compared the likelihood of multiple potential environmental determinants of heterochrony. We gathered data on the proportion of paedomorphic and metamorphic palmate newts (Lissotriton helveticus) across more than 150 populations during 10 years, and used an information-theoretic approach to compare the support of multiple potential processes. 3. Six environmental processes jointly explained the proportion of paedomorphs in populations: predation, water availability, dispersal limitation, aquatic breathing, terrestrial habitat suitability, and anti-predator refuges. Analyses of variation across space and time supported models based on the advantage of paedomorphosis in favourable aquatic habitats. 4. Paedomorphs were favoured in deep ponds, in conditions favourable to aquatic breathing (high oxygen content), with lack of fish, and surrounded by suitable terrestrial habitat. Metamorphs were favoured by banks allowing easy dispersal. 5. These results indicate that heterochrony relies on complex processes involving multiple ecological variables and exemplifies why heterochronic patterns occur in contrasted environments. On the other hand, the fast selection of alternative morphs shows that metamorphosis and paedomorphosis developmental modes could be easily disrupted in natural populations. [less ▲]

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See detailL'hétérogénéité de l'insuline cristalline
Fredericq, Léon ULg

in Archives Internationales de Physiologie (1953)

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See detailHétérogénéité des échelles spatio-temporelles d'écoulements hydrosédimentaires et modélisation numérique
Dewals, Benjamin ULg; Erpicum, Sébastien ULg; Archambeau, Pierre ULg et al

in Houille Blanche (2008), (5), 109-114

Les modèles numériques hydrosédimentaires doivent être aptes à prendre en compte la très grande hétérogénéité des échelles spatiales et surtout temporelles affectant les divers phénomènes à simuler. Pour ... [more ▼]

Les modèles numériques hydrosédimentaires doivent être aptes à prendre en compte la très grande hétérogénéité des échelles spatiales et surtout temporelles affectant les divers phénomènes à simuler. Pour ce faire, différents niveaux de couplage entre sous-modèles doivent être prévus (calcul hydrodynamique stationnaire, quasi stationnaire ou instationnaire complet). Outre une discussion du formalisme mathématique sous-jacent, la présente communication décrit le système de modélisation WOLF, développé à l’Université de Liège et permettant de couvrir la majorité des échelles de temps pertinentes au moyen d’approches numériques spécifiquement adaptées. L’applicabilité du système de modélisation est illustrée sur base de plusieurs exemples de simulations relatives à la conception et aux modes de gestion d’un grand ouvrage hydroélectrique en Inde. [less ▲]

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See detailHétérogénéité des échelles spatio-temporelles d’écoulements hydrosédimentaires et modélisation numérique
Dewals, Benjamin ULg; Erpicum, Sébastien ULg; Archambeau, Pierre ULg et al

in Articles du colloque Transports solides et gestion des sédiments en milieux naturels et urbains (2007)

The numerical models for flow and sediment transport must be able to handle properly the wide range of space- and time-scales relevant for the processes to be modelled. For this purpose different levels ... [more ▼]

The numerical models for flow and sediment transport must be able to handle properly the wide range of space- and time-scales relevant for the processes to be modelled. For this purpose different levels of numerical coupling between the flow solver and the sediment transport model must be considered. Besides a short review of the mathematical background, the present paper describes the modelling system WOLF, developed at the University of Liege and enabling to handle the vast majority of time scales characterizing practical applications of flows with sediment transport, by means of specific numerical techniques. The applicability of the modelling system is demonstrated based on several examples of simulations related to the design and the operation of a large hydroelectric project in India. [less ▲]

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See detailL'hétérogénéité des individus en terme de longévité et l'influence de celle-ci sur le caractère redistributif des pensions
Denomerenge, Jonathan ULg

Speech/Talk (2017)

Le système belge de pension comporte des éléments de redistribution en faveur des bas revenus. Cependant, l'espérance de vie d'un individu est corrélée positivement avec ses revenus. Par conséquent, les ... [more ▼]

Le système belge de pension comporte des éléments de redistribution en faveur des bas revenus. Cependant, l'espérance de vie d'un individu est corrélée positivement avec ses revenus. Par conséquent, les gens avec un revenu important bénéficient généralement de leur pension de retraite pendant un nombre d'année plus important, ce qui remet potentiellement en cause le caractère redistributif du système. [less ▲]

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See detailHétérogénéité, mon cher souci
Lafontaine, Dominique ULg

(2005, April)

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See detailHétérogénéité, mon cher souci
Lafontaine, Dominique ULg

in Revue Internationale d'Education (2005), 40

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See detailHeterogeneity of (co)variance components for Jersey type traits
Gengler, Nicolas ULg; Dusseldorf, T.; Wiggans, G. R. et al

in Journal of Dairy Science (2001), 84

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See detailHeterogeneity of brain glucose metabolism in mild cognitive impairment and clinical progression to Alzheimer disease
Anchisi, D.; Borroni, B.; Franceschi, M. et al

in Archives of Neurology (2005), 62(11), 1728-1733

Background: Subjects with amnesic mild cognitive impairment (aMCI) may include patients at high risk for progression to Alzheimer disease (AD) and a population with different underlying pathologic ... [more ▼]

Background: Subjects with amnesic mild cognitive impairment (aMCI) may include patients at high risk for progression to Alzheimer disease (AD) and a population with different underlying pathologic conditions. Objective: To evaluate the potential roles of positron emission tomography with fluodeoxyglucose F 18 ((18)FDG-PET) and memory scores in identifying subjects with aMCI and in predicting progression to dementia. Design, Setting, and Patients: Sixty-seven patients at European centers for neurologic and AD care who were diagnosed as having aMCI each underwent an extensive clinical and neuropsychological examination and an (18)FDG-PET study. Forty-eight subjects were followed up periodically for at least I year, and progression to dementia was evaluated. Main Outcome Measures: Brain glucose metabolism and memory scores. Results: Fourteen subjects with aMCI who converted to AD within 1 year showed bilateral hypometabolism in the inferior parietal, posterior cingulate, and medial temporal cortex. Subjects with "stable" aMCI presented with hypometabolism in the dorsolateral frontal cortex. The severity of memory impairment, as evaluated by the California Verbal Learning Test-Long Delay Free Recall scores, correlated with the following brain metabolic patterns: scores less than 7 were associated with a typical (18)FDG-PET AD pattern, and scores of 7 or higher were associated with hypornetabolism in the dorsolateral frontal cortex and no progression to AD. Conclusion: These data provide evidence for clinical and functional heterogeneity among subjects with aMCI and suggest that (18)FDG-PET findings combined with memory scores may be useful in predicting short-term conversion to AD. [less ▲]

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See detailHeterogeneity of follow-up procedures in French and Belgian patients with treated hereditary tyrosinemia type 1: results of a questionnaire and proposed guidelines.
Schiff, Manuel; Broue, Pierre; Chabrol, Brigitte et al

in Journal of inherited metabolic disease (2012), 35(5), 823-9

The 1991 introduction of 2-(2-nitro-4-trifluoro-methylbenzyol)-1,3 cyclohexanedione (NTBC) as a treatment for hereditary tyrosinemia type 1 (HT-1), a disorder of tyrosine catabolism, has radically ... [more ▼]

The 1991 introduction of 2-(2-nitro-4-trifluoro-methylbenzyol)-1,3 cyclohexanedione (NTBC) as a treatment for hereditary tyrosinemia type 1 (HT-1), a disorder of tyrosine catabolism, has radically modified the natural history of this disorder. Despite the dramatic improvements in survival, outcomes and quality of life seen with NTBC treatment, HT-1 remains a chronic disorder with several long-term complications, including, a persistent (albeit low) risk of hepatocellular carcinoma and suboptimal neuropsychological outcomes. There remain unsolved key-questions concerning the long-term outcomes of patients with HT-1, which closely depend on the quality of follow-up in these patients. In the absence of published guidelines, we investigated the follow-up methods used for French and Belgian patients with HT-1. A simple questionnaire providing a rapid overview of follow-up procedures was sent to the 19 physicians in charge of HT-1 patients treated with NTBC and low-tyrosine diet in France and Belgium. Several areas of heterogeneity (especially liver imaging, slit lamp examination, neuropsychological evaluation and maximal plasma tyrosine level accepted) were observed. In an attempt to improve long-term management and outcome of patients with HT-1, we proposed follow-up recommendations. [less ▲]

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See detailThe heterogeneity of headache patients who self-medicate: a cluster analysis approach.
Mehuys, Els; Paemeleire, Koen; Crombez, Geert et al

in Pain (2016), 157(7), 1464-71

Patients with headache often self-treat their condition with over-the-counter analgesics. However, overuse of analgesics can cause medication-overuse headache. The present study aimed to identify ... [more ▼]

Patients with headache often self-treat their condition with over-the-counter analgesics. However, overuse of analgesics can cause medication-overuse headache. The present study aimed to identify subgroups of individuals with headache who self-medicate, as this could be helpful to tailor intervention strategies for prevention of medication-overuse headache. Patients (n = 1021) were recruited from 202 community pharmacies and completed a self-administered questionnaire. A hierarchical cluster analysis was used to group patients as a function of sociodemographics, pain, disability, and medication use for pain. Three patient clusters were identified. Cluster 1 (n = 498, 48.8%) consisted of relatively young individuals, and most of them suffered from migraine. They reported the least number of other pain complaints and the lowest prevalence of medication overuse (MO; 16%). Cluster 2 (n = 301, 29.5%) included older persons with mainly non-migraine headache, a low disability, and on average pain in 2 other locations. Prevalence of MO was 40%. Cluster 3 (n = 222, 21.7%) mostly consisted of patients with migraine who also report pain in many other locations. These patients reported a high disability and a severe limitation of activities. They also showed the highest rates of MO (73%). [less ▲]

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See detailHeterogeneity of multitasking abilities in schizophrenia.
Laloyaux, Julien ULg; Van der Linden, Martial ULg; Laroi, Frank ULg

in Van Overwalle, Frank; Uzieblo, Kasia; Rossi, Gina (Eds.) et al Abstract book of the Annual meeting of the Belgian Association for Psychological Sciences (2015)

Difficulties in everyday life activities are core features of persons diagnosed with schizophrenia, and in particular for those activities requiring multitasking capacities. Multitasking refers to ... [more ▼]

Difficulties in everyday life activities are core features of persons diagnosed with schizophrenia, and in particular for those activities requiring multitasking capacities. Multitasking refers to activities (e.g. preparing a meal) where the person has to: (a) carry out and alternate between different tasks that vary in terms of priority, difficulty and duration; (b) define the tasks’ targets; (c) and face unexpected problems during the realization of these tasks. Moreover, schizophrenia is characterized by a great heterogeneity in regard to their everyday life difficulties and cognitive functioning. At present, patients’ multitasking capacities have not been adequately examined in the literature due to an absence of suitable assessment strategies. We thus recently developed a computerized real-life activity task designed to take into account the complex and multitasking nature of certain everyday life activities where participants are required to prepare a room for a meeting (i.e. the Computerized Meeting Preparation Task, CMPT). The aim of this study was to examine the multitasking abilities in persons diagnosed with schizophrenia and in particular the existence of subgroups of patients in regard to their performances on cognitive measures and on the CMPT. Sixty-two patients diagnosed with schizophrenia and 39 paired healthy controls completed the CMPT and a cognitive battery. The results reveal that the CMPT possesses good sensitivity and suggest three underlying constructs of multitasking (Memory, Planning and Intent), which were found to be underpinned by several cognitive functions and multitasking aspects. Moreover, cluster analyses revealed subgroups of patients differing in terms of their cognitive and CMPT performances. Taken together, these results show the need for a cognitive model of multitasking abilities in persons diagnosed with schiozphrenia. Taken together, this cognitive model and the CMPT, could be a good basis for cognitive interventions of multitasking abilities in schizophrenia. Finally, the results underline the heterogeneity of schizophrenia. [less ▲]

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See detailHeterogeneity of multitasking abilities in schizophrenia.
Laloyaux, Julien ULg; Van der Linden, Martial ULg; Laroi, Frank ULg

Conference (2015, May 28)

Difficulties in everyday life activities are core features of persons diagnosed with schizophrenia, and in particular for those activities requiring multitasking capacities. Multitasking refers to ... [more ▼]

Difficulties in everyday life activities are core features of persons diagnosed with schizophrenia, and in particular for those activities requiring multitasking capacities. Multitasking refers to activities (e.g. preparing a meal) where the person has to: (a) carry out and alternate between different tasks that vary in terms of priority, difficulty and duration; (b) define the tasks’ targets; (c) and face unexpected problems during the realization of these tasks. Moreover, schizophrenia is characterized by a great heterogeneity in regard to their everyday life difficulties and cognitive functioning. At present, patients’ multitasking capacities have not been adequately examined in the literature due to an absence of suitable assessment strategies. We thus recently developed a computerized real-life activity task designed to take into account the complex and multitasking nature of certain everyday life activities where participants are required to prepare a room for a meeting (i.e. the Computerized Meeting Preparation Task, CMPT). The aim of this study was to examine the multitasking abilities in persons diagnosed with schizophrenia and in particular the existence of subgroups of patients in regard to their performances on cognitive measures and on the CMPT. Sixty-two patients diagnosed with schizophrenia and 39 paired healthy controls completed the CMPT and a cognitive battery. The results reveal that the CMPT possesses good sensitivity and suggest three underlying constructs of multitasking (Memory, Planning and Intent), which were found to be underpinned by several cognitive functions and multitasking aspects. Moreover, cluster analyses revealed subgroups of patients differing in terms of their cognitive and CMPT performances. Taken together, these results show the need for a cognitive model of multitasking abilities in persons diagnosed with schiozphrenia. Taken together, this cognitive model and the CMPT, could be a good basis for cognitive interventions of multitasking abilities in schizophrenia. Finally, the results underline the heterogeneity of schizophrenia. [less ▲]

Detailed reference viewed: 30 (2 ULg)