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See detailThe role of metallothioneins, selenium and transfer to offspring in mercury detoxification in Franciscana dolphins (Pontoporia blainvillei)
Romero, M.B.; Pollizi, P.; Chiodi, L. et al

in Marine Pollution Bulletin (2016)

The concentrations of mercury (Hg), selenium (Se) and metallothioneins (MT) were evaluated in fetuses, calves, juveniles and adults of the endangered coastal Franciscana dolphin (Pontoporia blainvillei ... [more ▼]

The concentrations of mercury (Hg), selenium (Se) and metallothioneins (MT) were evaluated in fetuses, calves, juveniles and adults of the endangered coastal Franciscana dolphin (Pontoporia blainvillei) from Argentina. Mercury concentrations varied among analyzed tissues (liver, kidney, muscle and brain), with liver showing the higher concentrations in all specimens. An age-dependent accumulation was found in liver, kidney and brain. No significant relationship between Hg and MT concentrations was found for all tissues analyzed. Hepatic Hg molar concentrations were positively correlated with those of Se, indicating a great affinity between these two elements. Furthermore, dark granules of HgSe were observed in Kupffer cells in the liver by electron microscopy, suggesting the role of this macrophage in the detoxification of Hg. A transfer of Hg through placenta was proved. The presence of Hg in brain in all age classes did not show concentrations associated with neurotoxicity. [less ▲]

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See detailStaphylococcus aureus genotype B and other genotypes isolated from cow milk in European countries.
Cosandey, A.; Boss, R.; Luini, M. et al

in Journal of dairy science (2016), 99(1), 529-40

Staphylococcus aureus is globally one of the most important pathogens causing contagious mastitis in cattle. Previous studies, however, have demonstrated in Swiss cows that Staph. aureus isolated from ... [more ▼]

Staphylococcus aureus is globally one of the most important pathogens causing contagious mastitis in cattle. Previous studies, however, have demonstrated in Swiss cows that Staph. aureus isolated from bovine intramammary infection is genetically heterogeneous, with Staph. aureus genotype B (GTB) and GTC being the most prominent genotypes. In addition, Staph. aureus GTB was found to be contagious, whereas Staph. aureus GTC and all the remaining genotypes were involved in individual cow disease. The aim of this study was to subtype strains of Staph. aureus isolated from bovine mastitic milk and bulk tank milk to obtain a unified view of the presence of bovine staphylococcal subtypes in 12 European countries. A total of 456 strains of Staph. aureus were subjected to different typing methods: ribosomal spacer PCR, detection of enterotoxin genes, and detection of gene polymorphisms (lukE, coa). Major genotypes with their variants were combined into genotypic clusters (CL). This study revealed 5 major CL representing 76% of all strains and comprised CLB, CLC, CLF, CLI, and CLR. The clusters were characterized by the same genetic properties as the Swiss isolates, demonstrating high clonality of bovine Staph. aureus. Interestingly, CLB was situated in central Europe whereas the other CL were widely disseminated. The remaining 24% of the strains comprised 41 genotypes and variants, some of which (GTAM, GTBG) were restricted to certain countries; many others, however, were observed only once. [less ▲]

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See detailBovine Staphylococcus aureus: Subtyping, evolution, and zoonotic transfer.
Boss, R.; Cosandey, A.; Luini, M. et al

in Journal of dairy science (2016), 99(1), 515-28

Staphylococcus aureus is globally one of the most important pathogens causing contagious mastitis in cattle. Previous studies using ribosomal spacer (RS)-PCR, however, demonstrated in Swiss cows that ... [more ▼]

Staphylococcus aureus is globally one of the most important pathogens causing contagious mastitis in cattle. Previous studies using ribosomal spacer (RS)-PCR, however, demonstrated in Swiss cows that Staph. aureus isolated from bovine intramammary infections are genetically heterogeneous, with Staph. aureus genotype B (GTB) and GTC being the most prominent genotypes. Furthermore, Staph. aureus GTB was found to be contagious, whereas Staph. aureus GTC and all the remaining genotypes were involved in individual cow disease. In addition to RS-PCR, other methods for subtyping Staph. aureus are known, including spa typing and multilocus sequence typing (MLST). They are based on sequencing the spa and various housekeeping genes, respectively. The aim of the present study was to compare the 3 analytic methods using 456 strains of Staph. aureus isolated from milk of bovine intramammary infections and bulk tanks obtained from 12 European countries. Furthermore, the phylogeny of animal Staph. aureus was inferred and the zoonotic transfer of Staph. aureus between cattle and humans was studied. The analyzed strains could be grouped into 6 genotypic clusters, with CLB, CLC, and CLR being the most prominent ones. Comparing the 3 subtyping methods, RS-PCR showed the highest resolution, followed by spa typing and MLST. We found associations among the methods but in many cases they were unsatisfactory except for CLB and CLC. Cluster CLB was positive for clonal complex (CC)8 in 99% of the cases and typically positive for t2953; it is the cattle-adapted form of CC8. Cluster CLC was always positive for tbl 2645 and typically positive for CC705. For CLR and the remaining subtypes, links among the 3 methods were generally poor. Bovine Staph. aureus is highly clonal and a few clones predominate. Animal Staph. aureus always evolve from human strains, such that every human strain may be the ancestor of a novel animal-adapted strain. The zoonotic transfer of IMI- and milk-associated strains of Staph. aureus between cattle and humans seems to be very limited and different hosts are not considered as a source for mutual, spontaneous infections. Spillover events, however, may happen. [less ▲]

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See detailManaging age diversity in companies: transferring competences between generations at work – Project Génération+
Dujardin, Jean-Marie ULg; Randaxhe, David ULg

in Field, John; Schmidt-Hertha, Bernhard; Waxenegger, Andrea (Eds.) Universities and Engagement - International perspectives on higher education and lifelong learning (2016)

The book will offer an answer to the question ‘What can be understood by University Lifelong Learning today?’ by collating the work of specialists from across Europe and beyond who have first-hand ... [more ▼]

The book will offer an answer to the question ‘What can be understood by University Lifelong Learning today?’ by collating the work of specialists from across Europe and beyond who have first-hand experience in the field of university engagement through continuing education. With a diverse range of expertise from the UK, Ireland, Germany, Finland, Malta, Belgium, New Zealand, Austria and the USA, readers are guaranteed a varied and informative collection of perspectives on this important topic. Taken as a whole, the book provides a theoretical background for readers, drawing on recent research and practice examples from a variety of countries and institutional settings, as well as demonstrating a variety of conceptual approaches, confirming the diverse range of possible solutions. Key topics covered include: - research into policy and practice; - engaging with business and industry; - engaging with communities; - engaging with an ageing society; - active citizenship and regional competitiveness. Developed in collaboration with the European University Continuing Education Network (EUCEN), Universities and Engagement is an invaluable contribution to research in the subject of lifelong learning. It will be of value to academics, practitioners and professionals with an interest in higher education and community management, and will be particularly suited to those interested in lifelong learning, adult education and community development. [less ▲]

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See detailSubunit Asa1 spans all the peripheral stalk of the mitochondrial ATP synthase of the chlorophycean alga Polytomella sp.
Colina-Tenorio, Lilia; Miranda-Astudillo, Hector; Cano-Estrada, Araceli et al

in Biochimica et biophysica acta (2016)

Mitochondrial F1FO-ATP synthase of chlorophycean algae is dimeric. It contains eight orthodox subunits (alpha, beta, gamma, delta, epsilon, OSCP, a and c) and nine atypical subunits (Asa1 to 9). These ... [more ▼]

Mitochondrial F1FO-ATP synthase of chlorophycean algae is dimeric. It contains eight orthodox subunits (alpha, beta, gamma, delta, epsilon, OSCP, a and c) and nine atypical subunits (Asa1 to 9). These subunits build the peripheral stalk of the enzyme and stabilize its dimeric structure. The location of the 66.1kDa subunit Asa1 has been debated. On one hand, it was found in a transient subcomplex that contained membrane-bound subunits Asa1/Asa3/Asa5/Asa8/a (Atp6)/c (Atp9). On the other hand, Asa1 was proposed to form the bulky structure of the peripheral stalk that contacts the OSCP subunit in the F1 sector. Here, we overexpressed and purified the recombinant proteins Asa1 and OSCP and explored their interactions in vitro, using immunochemical techniques and affinity chromatography. Asa1 and OSCP interact strongly, and the carboxy-terminal half of OSCP seems to be instrumental for this association. In addition, the algal ATP synthase was partially dissociated at relatively high detergent concentrations, and an Asa1/Asa3/Asa5/Asa8/a/c10 subcomplex was identified. Furthermore, Far-Western analysis suggests an Asa1-Asa8 interaction. Based on these results, a model is proposed in which Asa1 spans the whole peripheral arm of the enzyme, from a region close to the matrix-exposed side of the mitochondrial inner membrane to the F1 region where OSCP is located. 3D models show elongated, helix-rich structures for chlorophycean Asa1 subunits. Asa1 subunit probably plays a scaffolding role in the peripheral stalk analogous to the one of subunit b in orthodox mitochondrial enzymes. [less ▲]

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See detailDetecting urban road network accessibility problems using taxi GPS data
Cui, JianXun; Liu, Feng; Janssens, Davy et al

in Journal of Transport Geography (2016), 51

Urban population growth and economic development have led to the creation of new communities, jobs and services at places where the existing road network might not cover or efficiently handle traffic ... [more ▼]

Urban population growth and economic development have led to the creation of new communities, jobs and services at places where the existing road network might not cover or efficiently handle traffic. This generates isolated pockets of areas which are difficult to reach through the transport system. To address this accessibility problem, we have developed a novel approach to systematically examine the current urban land use and road network conditions as well as to identify poorly connected regions, using GPS data collected from taxis. This method is composed of four major steps. First, city-wide passenger travel demand patterns and travel times are modeled based on GPS trajectories. Upon this model, high density residential regions are then identified, and measures to assess accessibility of each of these places are developed. Next, the regions with the lowest level of accessibility among all the residential areas are detected, and finally the detected regions are further examined and specific transport situations are analyzed. By applying the proposed method to the Chinese city of Harbin, we have identified 20 regions that have the lowest level of accessibility by car among all the identified residential areas. A serious reachability problem to petrol stations has also been discovered, in which drivers from 92.6% of the residential areas have to travel longer than 30 min to refill their cars. Furthermore, the comparison against a baseline model reveals the capacity of the derived measures in accounting for the actual travel routes under divergent traffic conditions. The experimental results demonstrate the potential and effectiveness of the proposed method in detecting car-based accessibility problems, contributing towards the development of urban road networks into a system that has better reachability and more reduced inequity. [less ▲]

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See detailBest Practice Guidelines for Cooperative Compliance with Nuclear Non-Proliferation Obligations
Colussi, Ilaria Anna ULg; Martellini, Maurizio

in Black-Branch, Jonathan; Fleck, Dieter (Eds.) Nuclear Non-Proliferation in International Law, Volume II, Verification and Compliance (2016)

The role of the law in front of nuclear technologies and nuclear weapons is a meaningful one. The law is aimed to regulate the existing nuclear activities, or – at a preliminary stage – to (try to ... [more ▼]

The role of the law in front of nuclear technologies and nuclear weapons is a meaningful one. The law is aimed to regulate the existing nuclear activities, or – at a preliminary stage – to (try to) prevent and govern the risks arising from the misuse of nuclear technologies, or to tackle the problem of nuclear proliferation. However, on many occasions, it appears that the law is inefficient to deal with these issues. Thus, the paper proposes some “best practice” legal ways to be followed, in order to build a cooperative nuclear compliance at a global level. The analysis starts from the focus on the Treaty of Non-Proliferation (NPT), highlighting the content of Article VI as judicially interpreted by the International Court of Justice, and examining the gaps and limits that the NPT still owns. After defining the notions of “verification, compliance and enforcement”, the paper concentrates on some methods and mechanisms that have been established at the international law level in general, with the purpose to obtain the respect of international rules. In the belief that the comparison could be useful as a “source of inspiration” for the nuclear non-proliferation, the chosen ways of verification and compliance pertain to the area of environmental law and trade law. On the basis of such comparison, a set of guidelines for enhancing cooperative compliance in the nuclear field is concretely offered. In particular, it is stressed to (a) collect and monitor the data; (b) reinforce the structure and action of the International Atomic Energy Agency (IAEA); (c) involve other UN bodies, of States and civil society; and (d) follow the principles of (i) the rule of law, (ii) impartiality and non-discrimination, (iii) transparency, and (iv) responsibility. [less ▲]

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See detailReview of dietary supplements for the management of osteoarthritis in dogs in studies from 2004 to 2014
Comblain, Fanny ULg; Serisier, Samuel; Barthelemy, Nicolas ULg et al

in Journal of Veterinary Pharmacology & Therapeutics (2016), 39

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See detailL’intervention
Moreau, Pierre ULg

in L'instance (2016)

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See detailA Belgian Survey on Geriatric Assessment in Oncology Focusing on Large-Scale Implementation and Related Barriers and Facilitators.
Kenis, C.; Heeren, P.; Decoster, L. et al

in The journal of nutrition, health & aging (2016), 20(1), 60-70

OBJECTIVES: The aim of this study is to describe a large-scale, Belgian implementation project about geriatric assessment (=GA) in daily oncology practice and to identify barriers and facilitators for ... [more ▼]

OBJECTIVES: The aim of this study is to describe a large-scale, Belgian implementation project about geriatric assessment (=GA) in daily oncology practice and to identify barriers and facilitators for implementing GA in this setting. Design / setting / participants: The principal investigator of every participating hospital (n=22) was invited to complete a newly developed questionnaire with closed- and open-ended questions. The closed-ended questions surveyed how GA was implemented. The open-ended questions identified barriers and facilitators for the implementation of GA in daily oncology practice. Descriptive statistics and conventional content analysis were performed as appropriate. RESULTS: Qualifying criteria (e.g. disease status and cancer type) for GA varied substantially between hospitals. Thirteen hospitals (59.1%) succeeded to screen more than half of eligible patients. Most hospitals reported that GA data and follow-up data had been collected in almost all screened patients. Implementing geriatric recommendations and formulating new geriatric recommendations at the time of follow-up are important opportunities for improvement. The majority of identified barriers were organizational, with high workload, lack of time or financial/staffing problems as most cited. The most cited facilitators were all related to collaboration. CONCLUSION: Interventions to improve the implementation of GA in older patients with cancer need to address a wide range of factors, with organization and collaboration as key elements. All stakeholders, seeking to improve the implementation of GA in older patients with cancer, should consider and address the identified barriers and facilitators. [less ▲]

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See detailOsteoarthritis year in review 2015: soluble biomarkers and the BIPED criteria.
Bay-Jensen, A. C.; Reker, D.; Kjelgaard-Petersen, C. F. et al

in Osteoarthritis and cartilage / OARS, Osteoarthritis Research Society (2016), 24(1), 9-20

OBJECTIVE: To review and summarize biomarker data published from April 2014 to May 2015 to provide insight to the ongoing work in the field of osteoarthritis (OA). Furthermore, to summarize the BIPED ... [more ▼]

OBJECTIVE: To review and summarize biomarker data published from April 2014 to May 2015 to provide insight to the ongoing work in the field of osteoarthritis (OA). Furthermore, to summarize the BIPED criteria and set it in context of the medical needs of 2015. METHODS: PubMed was used as searching machine: Time period 2014/04/01-2015/05/01, MeSH term [Biomarker] AND [Osteoarthritis], Language; English, Full text available. Reviews were excluded. Only papers describing protein based biomarkers measured in human body fluids from OA patients were included. RESULTS: Biomarkers of joint tissue turnover, cytokines, chemokines and peptide arrays were measured in different cohorts and studies. Amongst those were previously tested biomarkers such as osteocalcin, Carboxy-terminal cross-linked fragment of type II collagen (CTX-II) and cartilage oligomeric matrix protein (COMP). A majority of the biomarker were classified as I, B or B biomarkers according to the BIPED criteria. Work is continuing on testing biomarkers in OA. There is still a huge, unmet medical need to identify, test, validate and qualify novel and well-known biomarkers. A pre-requisite for this is better characterization and classification of biomarkers to their needs, which may not be reached before higher understanding of OA phenotypes has been gained. In addition, we provide some references to some recent guidelines from Food and Drug Administration (FDA) and European Medicines Agency (EMA) on qualification and usage of biomarkers for drug development and personalized medicine, which may provide value to the field. [less ▲]

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See detailAdaptation et neurosciences I : craintes, société, méthodologie, finalité
Desseilles, Martin ULg

in Santé Mentale au Québec (2016), XL(3), 209-221

Cetarticleestlepremierdedeuxarticlesexplorantlesliensbidirection- nels entre le concept d’adaptation et celui de neurosciences. Nous verrons tout d’abord dans cet article que les neurosciences peuvent ... [more ▼]

Cetarticleestlepremierdedeuxarticlesexplorantlesliensbidirection- nels entre le concept d’adaptation et celui de neurosciences. Nous verrons tout d’abord dans cet article que les neurosciences peuvent être perçues comme ambi- tieuses et toutes-puissantes oscillant entre un danger réductionniste et déshuma- nisant ou bien cristallisant certains fantasmes de maîtrise. Nous verrons ensuite que la société s’adapte aux neurosciences en intégrant certaines méthodologies et certaines découvertes dans des domaines très variés, au point que nous pouvons nous questionner sur la neurosociété de demain. Ensuite nous verrons que la méthodologie des neurosciences est elle-même fréquemment remise en question et nécessite que chacun en connaisse les limites sans s’en tenir aux seules pro- messes. Après cela, nous verrons que l’adaptation vue comme une promesse d’un but déterminé et fini peut s’avérer rassurante mais est surtout improbable. [less ▲]

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See detailSequential treatment with 5-aza-2'-deoxycytidine and deacetylase inhibitors reactivates HIV-1.
Bouchat, Sophie; Delacourt, Nadege; Kula, Anna et al

in EMBO molecular medicine (2016)

Reactivation of HIV gene expression in latently infected cells together with an efficient cART has been proposed as an adjuvant therapy aimed at eliminating/decreasing the reservoir size. Results from HIV ... [more ▼]

Reactivation of HIV gene expression in latently infected cells together with an efficient cART has been proposed as an adjuvant therapy aimed at eliminating/decreasing the reservoir size. Results from HIV clinical trials using deacetylase inhibitors (HDACIs) question the efficiency of these latency-reversing agents (LRAs) used alone and underline the need to evaluate other LRAs in combination with HDACIs. Here, we evaluated the therapeutic potential of a demethylating agent (5-AzadC) in combination with clinically tolerable HDACIs in reactivating HIV-1 from latency first in vitro and next ex vivo. We showed that a sequential treatment with 5-AzadC and HDACIs was more effective than the corresponding simultaneous treatment both in vitro and ex vivo. Interestingly, only two of the sequential LRA combinatory treatments tested induced HIV-1 particle recovery in a higher manner than the drugs alone ex vivo and at concentrations lower than the human tolerable plasmatic concentrations. Taken together, our data reveal the benefit of using combinations of 5-AzadC with an HDACI and, for the first time, the importance of treatment time schedule for LRA combinations in order to reactivate HIV. [less ▲]

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See detailTreacher Collins syndrome: a clinical and molecular study based on a large series of patients.
Vincent, Marie; Genevieve, David; Ostertag, Agnes et al

in Genetics in medicine : official journal of the American College of Medical Genetics (2016), 18(1), 49-56

PURPOSE: Treacher Collins/Franceschetti syndrome (TCS; OMIM 154500) is a disorder of craniofacial development belonging to the heterogeneous group of mandibulofacial dysostoses. TCS is classically ... [more ▼]

PURPOSE: Treacher Collins/Franceschetti syndrome (TCS; OMIM 154500) is a disorder of craniofacial development belonging to the heterogeneous group of mandibulofacial dysostoses. TCS is classically characterized by bilateral mandibular and malar hypoplasia, downward-slanting palpebral fissures, and microtia. To date, three genes have been identified in TCS:,TCOF1, POLR1D, and POLR1C. METHODS: We report a clinical and extensive molecular study, including TCOF1, POLR1D, POLR1C, and EFTUD2 genes, in a series of 146 patients with TCS. Phenotype-genotype correlations were investigated for 19 clinical features, between TCOF1 and POLR1D, and the type of mutation or its localization in the TCOF1 gene. RESULTS: We identified 92/146 patients (63%) with a molecular anomaly within TCOF1, 9/146 (6%) within POLR1D, and none within POLR1C. Among the atypical negative patients (with intellectual disability and/or microcephaly), we identified four patients carrying a mutation in EFTUD2 and two patients with 5q32 deletion encompassing TCOF1 and CAMK2A in particular. Congenital cardiac defects occurred more frequently among patients with TCOF1 mutation (7/92, 8%) than reported in the literature. CONCLUSION: Even though TCOF1 and POLR1D were associated with extreme clinical variability, we found no phenotype-genotype correlation. In cases with a typical phenotype of TCS, 6/146 (4%) remained with an unidentified molecular defect.Genet Med 18 1, 49-56. [less ▲]

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See detailCombined chondroitin sulfate and glucosamine for painful knee osteoarthritis: a multicentre, randomised, double-blind, non-inferiority trial versus celecoxib
Hochberg, M. C.; Martel-Pelletier, J.; Monfort, J. et al

in Ann Rheum Dis (2016), 75(1), 37-44

OBJECTIVES: To compare the efficacy and safety of chondroitin sulfate plus glucosamine hydrochloride (CS+GH) versus celecoxib in patients with knee osteoarthritis and severe pain. METHODS: Double-blind ... [more ▼]

OBJECTIVES: To compare the efficacy and safety of chondroitin sulfate plus glucosamine hydrochloride (CS+GH) versus celecoxib in patients with knee osteoarthritis and severe pain. METHODS: Double-blind Multicentre Osteoarthritis interVEntion trial with SYSADOA (MOVES) conducted in France, Germany, Poland and Spain evaluating treatment with CS+GH versus celecoxib in 606 patients with Kellgren and Lawrence grades 2-3 knee osteoarthritis and moderate-to-severe pain (Western Ontario and McMaster osteoarthritis index (WOMAC) score >/=301; 0-500 scale). Patients were randomised to receive 400 mg CS plus 500 mg GH three times a day or 200 mg celecoxib every day for 6 months. The primary outcome was the mean decrease in WOMAC pain from baseline to 6 months. Secondary outcomes included WOMAC function and stiffness, visual analogue scale for pain, presence of joint swelling/effusion, rescue medication consumption, Outcome Measures in Rheumatology Clinical Trials and Osteoarthritis Research Society International (OMERACT-OARSI) criteria and EuroQoL-5D. RESULTS: The adjusted mean change (95% CI) in WOMAC pain was -185.7 (-200.3 to -171.1) (50.1% decrease) with CS+GH and -186.8 (-201.7 to -171.9) (50.2% decrease) with celecoxib, meeting the non-inferiority margin of -40: -1.11 (-22.0 to 19.8; p=0.92). All sensitivity analyses were consistent with that result. At 6 months, 79.7% of patients in the combination group and 79.2% in the celecoxib group fulfilled OMERACT-OARSI criteria. Both groups elicited a reduction >50% in the presence of joint swelling; a similar reduction was seen for effusion. No differences were observed for the other secondary outcomes. Adverse events were low and similarly distributed between groups. CONCLUSIONS: CS+GH has comparable efficacy to celecoxib in reducing pain, stiffness, functional limitation and joint swelling/effusion after 6 months in patients with painful knee osteoarthritis, with a good safety profile. TRIAL REGISTRATION NUMBER: NCT01425853. [less ▲]

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See detailCorrelation between resting state fMRI total neuronal activity and PET metabolism in healthy controls and patients with disorders of consciousness
Soddu, Andrea ULg; Gomez, Francisco; Heine, Lizette ULg et al

in Brain and Behavior (2016)

Introduction: The mildly invasive 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) is a well-established imaging technique to measure ‘resting state’ cerebral metabolism. This technique made ... [more ▼]

Introduction: The mildly invasive 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) is a well-established imaging technique to measure ‘resting state’ cerebral metabolism. This technique made it possible to assess changes in metabolic activity in clinical applications, such as the study of severe brain injury and disorders of consciousness. Objective: We assessed the possi- bility of creating functional MRI activity maps, which could estimate the rela- tive levels of activity in FDG-PET cerebral metabolic maps. If no metabolic absolute measures can be extracted, our approach may still be of clinical use in centers without access to FDG-PET. It also overcomes the problem of recogniz- ing individual networks of independent component selection in functional mag- netic resonance imaging (fMRI) resting state analysis. Methods: We extracted resting state fMRI functional connectivity maps using independent component analysis and combined only components of neuronal origin. To assess neu- ronality of components a classification based on support vector machine (SVM) was used. We compared the generated maps with the FDG-PET maps in 16 healthy controls, 11 vegetative state/unresponsive wakefulness syndrome patients and four locked-in patients. Results: The results show a significant similarity with q = 0.75  0.05 for healthy controls and q = 0.58  0.09 for vegetative state/unresponsive wakefulness syndrome patients between the FDG- PET and the fMRI based maps. FDG-PET, fMRI neuronal maps, and the conjunction analysis show decreases in frontoparietal and medial regions in vegetative patients with respect to controls. Subsequent analysis in locked-in syndrome patients produced also consistent maps with healthy controls. Conclusions: The constructed resting state fMRI functional connectivity map points toward the possibility for fMRI resting state to estimate relative levels of activity in a metabolic map. [less ▲]

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See detailCombining feature extraction methods to assist the diagnosis of Alzheimer’s disease
Segovia, Fermin; Gorriz, J. M.; Ramirez, J. et al

in Current Alzheimer Research (2016)

Neuroimaging data as 18F-FDG PET is widely used to assist the diagnosis of Alzheimer’s disease (AD). Looking for regions with hypoperfusion/ hypometabolism, clinicians may predict or corroborate the ... [more ▼]

Neuroimaging data as 18F-FDG PET is widely used to assist the diagnosis of Alzheimer’s disease (AD). Looking for regions with hypoperfusion/ hypometabolism, clinicians may predict or corroborate the diagnosis of the patients. Modern computer aided diagnosis (CAD) systems based on the statistical analysis of whole neuroimages are more accurate than classical systems based on quantifying the uptake of some predefined regions of interests (ROIs). In addition, these new systems allow determining new ROIs and take advantage of the huge amount of information comprised in neuroimaging data. A major branch of modern CAD systems for AD is based on multivariate techniques, which analyse a neuroimage as a whole, considering not only the voxel intensities but also the relations among them. In order to deal with the vast dimensionality of the data, a number of feature extraction methods have been successfully applied. In this work, we propose a CAD system based on the combination of several feature extraction techniques. First, some commonly used feature extraction methods based on the analysis of the variance (as principal component analysis), on the factorization of the data (as non-negative matrix factorization) and on classical magnitudes (as Haralick features) were simultaneously applied to the original data. These feature sets were then combined by means of two different combination approaches: i) using a single classifier and a multiple kernel learning approach and ii) using an ensemble of classifier and selecting the final decision by majority voting. The proposed approach was evaluated using a labelled neuroimaging database along with a cross validation scheme. As conclusion, the proposed CAD system performed better than approaches using only one feature extraction technique. We also provide a fair comparison (using the same database). - See more at: http://www.eurekaselect.com/136992/article#sthash.PPiyE35K.dpuf [less ▲]

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See detailNew Insight on the Performance of Equity Long/short Investment Styles
Fays, Boris ULg; Hübner, Georges ULg; Lambert, Marie ULg

in Bankers, Markets, Investors (2016), 140(January-February), 34-45

Long-short equity strategies have recently generated exceptional performance raising a set of concerns about the strategies’ propensity to deliver alpha or beta. This paper revisits the performance of ... [more ▼]

Long-short equity strategies have recently generated exceptional performance raising a set of concerns about the strategies’ propensity to deliver alpha or beta. This paper revisits the performance of equity long-short hedge funds across investments styles. We first categorize individual hedge funds with regard to their size and/or value factor investing along the generalization of Sharpe (1992) style analysis. Style weights on size and value factors are used to split the equity long-short universe in 5x5 hedge fund style portfolios. To analyze the performance of each style, we consider two sets of innovative factors. First, we apply sequential Fama-French model of Lambert, Fays and Hübner (2015). Besides, to captures downside and extreme risk embedded in hedge fund strategies we augment the model with the co-skewness and co-kurtosis factors developed by Lambert and Hübner (2013). Under this framework, we perform cross-sectional performance analyses of individual hedge funds as well as time-series analysis on the hedge fund style broad category. Our contributions are threefold; first, our alternative framework significantly improves the explanatory power of the multi-factor model in the context of long-short equity funds, second, considering higher-moment factors aim to capture part of the abnormal return of the downside and extreme risk exposures taken by a fund manager, and finally, long-short equity hedge funds are, to some extent, less exposed to small capitalisation stocks than expected and instead rather prefer higher momentum levels in their strategies. [less ▲]

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See detailPathologies du tendon - Tendinopathies - Traitements 2
KAUX, Jean-François ULg

Learning material (2016)

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