Browsing Complete repository Arts & humanities   Archaeology   Art & art history   Classical & oriental studies   History   Languages & linguistics   Literature   Performing arts   Philosophy & ethics   Religion & theology   Multidisciplinary, general & others Business & economic sciences   Accounting & auditing   Production, distribution & supply chain management   Finance   General management & organizational theory   Human resources management   Management information systems   Marketing   Strategy & innovation   Quantitative methods in economics & management   General economics & history of economic thought   International economics   Macroeconomics & monetary economics   Microeconomics   Economic systems & public economics   Social economics   Special economic topics (health, labor, transportation…)   Multidisciplinary, general & others Engineering, computing & technology   Aerospace & aeronautics engineering   Architecture   Chemical engineering   Civil engineering   Computer science   Electrical & electronics engineering   Energy   Geological, petroleum & mining engineering   Materials science & engineering   Mechanical engineering   Multidisciplinary, general & others Human health sciences   Alternative medicine   Anesthesia & intensive care   Cardiovascular & respiratory systems   Dentistry & oral medicine   Dermatology   Endocrinology, metabolism & nutrition   Forensic medicine   Gastroenterology & hepatology   General & internal medicine   Geriatrics   Hematology   Immunology & infectious disease   Laboratory medicine & medical technology   Neurology   Oncology   Ophthalmology   Orthopedics, rehabilitation & sports medicine   Otolaryngology   Pediatrics   Pharmacy, pharmacology & toxicology   Psychiatry   Public health, health care sciences & services   Radiology, nuclear medicine & imaging   Reproductive medicine (gynecology, andrology, obstetrics)   Rheumatology   Surgery   Urology & nephrology   Multidisciplinary, general & others Law, criminology & political science   Civil law   Criminal law & procedure   Criminology   Economic & commercial law   European & international law   Judicial law   Metalaw, Roman law, history of law & comparative law   Political science, public administration & international relations   Public law   Social law   Tax law   Multidisciplinary, general & others Life sciences   Agriculture & agronomy   Anatomy (cytology, histology, embryology...) & physiology   Animal production & animal husbandry   Aquatic sciences & oceanology   Biochemistry, biophysics & molecular biology   Biotechnology   Entomology & pest control   Environmental sciences & ecology   Food science   Genetics & genetic processes   Microbiology   Phytobiology (plant sciences, forestry, mycology...)   Veterinary medicine & animal health   Zoology   Multidisciplinary, general & others Physical, chemical, mathematical & earth Sciences   Chemistry   Earth sciences & physical geography   Mathematics   Physics   Space science, astronomy & astrophysics   Multidisciplinary, general & others Social & behavioral sciences, psychology   Animal psychology, ethology & psychobiology   Anthropology   Communication & mass media   Education & instruction   Human geography & demography   Library & information sciences   Neurosciences & behavior   Regional & inter-regional studies   Social work & social policy   Sociology & social sciences   Social, industrial & organizational psychology   Theoretical & cognitive psychology   Treatment & clinical psychology   Multidisciplinary, general & others      by title 0-9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z or enter first few letters:    OK Showing results 33061 to 33080 of 128267     1649 1650 1651 1652 1653 1654 1655 1656 1657 1658 1659     Direct evidence for ferroelectric polar distortion in ultrathin lead titanate perovskite filmsDespont, L.; Koitzsch, C.; Clerc, F. et alin Physical Review. B, Condensed Matter and Materials Physics (2006), 73X-ray photoelectron diffraction is used to directly probe the intracell polar atomic distortion and tetragonality associated with ferroelectricity in ultrathin epitaxial PbTiO3 films. Our measurements ... [more ▼]X-ray photoelectron diffraction is used to directly probe the intracell polar atomic distortion and tetragonality associated with ferroelectricity in ultrathin epitaxial PbTiO3 films. Our measurements, combined with ab initio calculations, unambiguously demonstrate noncentrosymmetry in films a few unit cells thick, imply that films as thin as three unit cells still preserve a ferroelectric polar distortion, and also show that there is no thick paraelectric dead layer at the surface. [less ▲]Detailed reference viewed: 12 (0 ULg) Direct evidence for gray seal (Halichoerus grypus) predation and scavenging on harbor porpoises (Phocoena phocoena)Bouveroux, T.; Kiszka, J.; Heithaus, R. et alin Marine Mammal Science (2014)Detailed reference viewed: 24 (0 ULg) Direct evidence for grey seal (Halichoerus grypus) predation and scavenging on harbour porpoises (Phocoena phocoena)Bouveroux, T.; Kiszka, J.; Jauniaux, Thierry et alConference (2014)Detailed reference viewed: 10 (0 ULg) Direct Evidence of Free Radical Production after Ischaemia and Reperfusion and Protective Effect of Desferrioxamine: Esr and Vitamin E StudiesDefraigne, Jean-Olivier ; Detry, Olivier ; Pincemail, Joël et alin European Journal of Vascular Surgery (1994), 8(5), 537-43After surgical renal revascularisation, warm renal ischaemia due to renal artery cross-clamping contributes to postoperative renal dysfunction. After reperfusion, free radicals are thought to be a ... [more ▼]After surgical renal revascularisation, warm renal ischaemia due to renal artery cross-clamping contributes to postoperative renal dysfunction. After reperfusion, free radicals are thought to be a significant cause of injury. Nevertheless, indisputable proof of free radical production is scarce, partly because of their transient nature. In this study, electron paramagnetic resonance and vitamin E levels were used to demonstrate the free radical production after renal ischaemia and reperfusion. Rabbit kidneys were submitted either to 15 or 60 minutes of ischaemia followed by reperfusion. A spin trap agent (alpha-phenyl-N-tert-butyl nitrone (PBN), 20mg/ml, 1 ml/min) was infused during reperfusion directly into the left renal artery via an aortic catheter before declamping. Blood samples were selectively drawn from the left renal vein for ESR analysis (Varian spectrometer E109) of lipidic residues extracted from blood samples. The vitamin E content of the left renal cortex was determined by HPLC procedure. The right renal cortex was used as a control for the vitamin E values. In the venous effluent, ESR analysis revealed the formation of a spectrum consisting of a triplet of asymmetric doublets. This signal resulted from the spin trapping by PBN of a mixture of both oxygen- and carbon- centred lipidic radicals. The amplitude of the signal which is proportional to the amount of free radicals was significantly higher after 60 minutes ischaemia than after 15 minutes.(ABSTRACT TRUNCATED AT 250 WORDS) [less ▲]Detailed reference viewed: 58 (1 ULg) Direct evidence of nonadherence to antiepileptic medication in refractory focal epilepsyCARPENTIER, Nicolas; Jonas, Jacques; Frismand, Solène et alin Epilepsia (2013), 54(1), 20-23Detailed reference viewed: 10 (0 ULg) Direct exoplanet detection and characterization using the ANDROMEDA method: Performance on VLT/NaCo dataCantalloube, F.; Mouillet, D.; Mugnier, L. M. et alin Astronomy and Astrophysics (2015), 582Context. The direct detection of exoplanets with high-contrast imaging requires advanced data processing methods to disentangle potential planetary signals from bright quasi-static speckles. Among them ... [more ▼]Context. The direct detection of exoplanets with high-contrast imaging requires advanced data processing methods to disentangle potential planetary signals from bright quasi-static speckles. Among them, angular differential imaging (ADI) permits potential planetary signals with a known rotation rate to be separated from instrumental speckles that are either statics or slowly variable. The method presented in this paper, called ANDROMEDA for ANgular Differential OptiMal Exoplanet Detection Algorithm is based on a maximum likelihood approach to ADI and is used to estimate the position and the flux of any point source present in the field of view. Aims. In order to optimize and experimentally validate this previously proposed method, we applied ANDROMEDA to real VLT/NaCo data. In addition to its pure detection capability, we investigated the possibility of defining simple and efficient criteria for automatic point source extraction able to support the processing of large surveys. Methods. To assess the performance of the method, we applied ANDROMEDA on VLT/NaCo data of TYC-8979-1683-1 which is surrounded by numerous bright stars and on which we added synthetic planets of known position and flux in the field. In order to accommodate the real data properties, it was necessary to develop additional pre-processing and post-processing steps to the initially proposed algorithm. We then investigated its skill in the challenging case of a well-known target, $\beta$ Pictoris, whose companion is close to the detection limit and we compared our results to those obtained by another method based on principal component analysis (PCA). Results. Application on VLT/NaCo data demonstrates the ability of ANDROMEDA to automatically detect and characterize point sources present in the image field. We end up with a robust method bringing consistent results with a sensitivity similar to the recently published algorithms, with only two parameters to be fine tuned. Moreover, the companion flux estimates are not biased by the algorithm parameters and do not require a posteriori corrections. Conclusions. ANDROMEDA is an attractive alternative to current standard image processing methods that can be readily applied to on-sky data. [less ▲]Detailed reference viewed: 21 (0 ULg) Direct experimental evidence for atomic tunneling of europium in crystalline Eu8Ga16Ge30Hermann, Raphaël ; Keppens, Veerle; Bonville, Pierre et alin Physical Review Letters (2006), 97(1), Mossbauer-effect and microwave absorption experimental evidence unambiguously demonstrates the presence of slow, similar to 450 MHz, tunneling of magnetic europium between four equivalent sites in ... [more ▼]Mossbauer-effect and microwave absorption experimental evidence unambiguously demonstrates the presence of slow, similar to 450 MHz, tunneling of magnetic europium between four equivalent sites in Eu8Ga16Ge30, a stoichiometric clathrate. Remarkably, six of the eight europium atoms, or 11% of the constituents in this solid, tunnel between these four sites separated by 0.55 angstrom. The off centering of the atoms or ions in crystalline clathrates appears to be a promising route for producing Rabi oscillators in solid-state materials. [less ▲]Detailed reference viewed: 10 (0 ULg) Direct extraction of hadronic form factors from elastic-scattering dataMartynov, E.; Cudell, Jean-René ; Lengyel, A.in Nuclear Physics B-Proceedings Supplements (2005, September), 146Non-forward elastic hadron-scattering data are collected and analysed within the Regge approach. Through an analysis of the data in small bins in t, we have directly extracted the pomeron trajectory and ... [more ▼]Non-forward elastic hadron-scattering data are collected and analysed within the Regge approach. Through an analysis of the data in small bins in t, we have directly extracted the pomeron trajectory and the hadronic form factors (or reggeon couplings). We found higher values than usually used for the intercept and for the slope of the soft pomeron trajectory. The presence of zeros in t for the effective hadronic form factors is emphasised. [less ▲]Detailed reference viewed: 13 (1 ULg) Direct identification of bacteria from BacT/ALERT anaerobic positive blood cultures by MALDI-TOF MS: MALDI Sepsityper kit versus an in-house saponin method for bacterial extraction.MEEX, Cécile ; Neuville, Florence; DESCY, Julie et alin Journal of Medical Microbiology (2012), 61In cases of bacteraemia, a rapid species identification of the causal agent directly from positive blood culture broths could assist clinicians in the timely targeting of empirical antimicrobial therapy ... [more ▼]In cases of bacteraemia, a rapid species identification of the causal agent directly from positive blood culture broths could assist clinicians in the timely targeting of empirical antimicrobial therapy. For this purpose, we evaluated the direct identification of micro-organisms from BacT/ALERT (bioMérieux) anaerobic positive blood cultures without charcoal using the Microflex matrix-assisted laser desorption/ionization (MALDI) time of flight MS (Bruker), after bacterial extraction by using two different methods: the MALDI Sepsityper kit (Bruker) and an in-house saponin lysis method. Bruker's recommended criteria for identification were expanded in this study, with acceptance of the species identification when the first three results with the best matches with the MALDI Biotyper database were identical, whatever the scores were. In total, 107 monobacterial cultures and six polymicrobial cultures from 77 different patients were included in this study. Among monomicrobial cultures, we identified up to the species level 67 and 66 % of bacteria with the MALDI Sepsityper kit and the saponin method, respectively. There was no significant difference between the two extraction methods. The direct species identification was particularly inconclusive for Gram-positive bacteria, as only 58 and 52 % of them were identified to the species level with the MALDI Sepsityper kit and the saponin method, respectively. Results for Gram-negative bacilli were better, with 82.5 and 90 % of correct identification to the species level with the MALDI Sepsityper kit and the saponin method, respectively. No misidentifications were given by the direct procedures when compared with identifications provided by the conventional method. Concerning the six polymicrobial blood cultures, whatever the extraction method used, a correct direct identification was only provided for one of the isolated bacteria on solid medium in all cases. The analysis of the time-to-result demonstrated a reduction in the turnaround time for identification ranging from 1 h 06 min to 24 h 44 min, when performing the blood culture direct identification in comparison with the conventional method, whatever the extraction method. [less ▲]Detailed reference viewed: 70 (13 ULg) Direct identification of bacteria from positive blood cultures by MALDI-TOF MS : MALDI Sepsityper kit (Bruker) VS home made saponin method for bacterial extractionMEEX, Cécile ; NEUVILLE, Florence; DESCY, Julie et alPoster (2011)Detailed reference viewed: 22 (6 ULg) Direct imaging of Earth-like planets: why we care about exozodisAbsil, Olivier ; Defrère, D.; Roberge, A. et alin Danchi, W. C.; Delplancke, F.; Rajagopal, J. K. (Eds.) Optical and Infrared Interferometry II (2010, July)The presence of large amounts of exozodiacal dust around nearby main sequence stars is considered as a potential threat for the direct detection of Earth-like exoplanets (exoEarths) with future space ... [more ▼]The presence of large amounts of exozodiacal dust around nearby main sequence stars is considered as a potential threat for the direct detection of Earth-like exoplanets (exoEarths) with future space-based coronagraphic and interferometric missions. In this paper, we estimate the amount of exozodiacal light that can be tolerated around various stellar types without jeopardizing the detection of exoEarths with a space-based visible coronagraph or a free-flying mid-infrared interferometer. We also address the possible effects of resonant structures in exozodiacal disks. We then review the sensitivity of current ground-based interferometric instruments to exozodiacal disks, based on classical visibility measurements and on the nulling technique. We show that the current instrumental performances are not sufficient to help prepare future exoEarth imaging missions, and discuss how new groundor space-based instruments could improve the current sensitivity to exozodiacal disks down to a suitable level. [less ▲]Detailed reference viewed: 32 (11 ULg) Direct imaging of extra-solar planets in star forming regions. Lessons learned from a false positive around IM Lup.Mawet, Dimitri; Absil, Olivier ; Riaud, Pierre et alin Astronomy and Astrophysics (2012), 544Context. Most planet imagers consist of ground-based adaptive optics coronagraphic cameras which are currently limited in contrast, sensitivity and astrometric precision, but advantageously observe in the ... [more ▼]Context. Most planet imagers consist of ground-based adaptive optics coronagraphic cameras which are currently limited in contrast, sensitivity and astrometric precision, but advantageously observe in the near-infrared window (1 - 5 µm). Because of these practical limitations, our current observational aim at detecting and characterizing planets puts heavy constraints on target selection, observing strategies, data reduction, and follow-up. Most surveys so far have thus targeted very young systems (1 - 100Myr) to catch the putative remnant thermal radiation of giant planets, which peaks in the near-infrared. They also favor systems in the solar neighborhood (d < 80 pc), which eases angular resolution requirements but also ensures a good knowledge of the distance and proper motion, which are critical to secure the planet status, and enable any subsequent characterization. Aims. Because of their youth, it is very tempting to target the nearby star forming regions, which are typically twice as far as the bulk of objects usually combed for planets by direct imaging. Probing these very interesting reservoirs in practice sets additional constraints that we review in this paper by presenting the planet search that we initiated in 2008 around the disk-bearing T Tauri star IM Lup, which is part of the Lupus star forming region (140-190 pc). Methods. We show and discuss why age determination, the choice of evolutionary model for both the central star and the planet, precise knowledge of the host star proper motion, relative or absolute (between different instruments) astrometric accuracy (including plate scale calibration), and patience are the key ingredients for exoplanet searches around more distant young stars. Results. Unfortunately, most of the time, precision and perseverance are not paying off: we discovered a candidate companion around IM Lup in 2008, which we report here to be a false positive event. We nevertheless review in details the lessons learned from our endeavor, and additionally present the best detection limits ever calculated for IM Lup. We also accessorily report on the successful use of innovative data reduction techniques, such as the damped-LOCI and iterative roll subtraction. [less ▲]Detailed reference viewed: 65 (4 ULg) Direct imaging, photometry and spectroscopy of gravitationally lensed quasarsRicci, Davide Doctoral thesis (2012)Detailed reference viewed: 25 (3 ULg) Direct Inclusion of Proximity-Effect Losses in Two-Dimensional Time-Domain Finite-Element Simulation of Electrical MachinesGyselinck, Johan; Dular, Patrick ; Geuzaine, Christophe et alin Proceedings of the 8th International Symposium on Electric and Magnetic Fields (EMF2009) (2009)This paper deals with eddy-current effects in the distributed winding of electrical machines, and in particular with the proximity effect and the associated losses. A previously proposed homogenization ... [more ▼]This paper deals with eddy-current effects in the distributed winding of electrical machines, and in particular with the proximity effect and the associated losses. A previously proposed homogenization method for windings in two-dimensional (2D) time-domain finite-element (FE) models is shown to be applicable without additional computational cost, producing a precise estimate of the instantaneous proximity-effect losses. The method is illustrated by considering the conductors in a single stator slot of a 3kW induction motor. The brute-force model, with fine discretisation of each conductor, and the homogenized model yield macroscopic results that are very close to each other. [less ▲]Detailed reference viewed: 73 (10 ULg) Direct induction of burst firing by SK channel blockade in serotonergic neurons in vivoRouchet, Nathalie; Waroux, Olivier ; Moreau, Jacqueline et alScientific conference (2007, November 04)Small conductance calcium-activated potassium channels (SK channels) are widely expressed throughout the central nervous system and underlie the medium afterhyperpolarization following a single or a train ... [more ▼]Small conductance calcium-activated potassium channels (SK channels) are widely expressed throughout the central nervous system and underlie the medium afterhyperpolarization following a single or a train of action potentials. It has been shown that they are involved in the regulation of the excitability and the firing pattern of several types of neurons. In vivo, serotonergic (5-HT) neurons of the dorsal raphe nucleus usually show a tonic pattern of discharge, but they can also display repetitive burst firing activity, usually involving doublets of closely spaced (< 20 ms) action potentials. It has been shown that burst firing is correlated with an increase in transmitter release and postsynaptic effects (Gartside et al., Neuroscience, 98, 295-300, 2000). We hypothesized that SK channels modulate the firing pattern of 5-HT neurons. In a preliminary study, extracellular single-cell recordings combined with iontophoresis showed that UCL1684, a water soluble SK blocker (200 µM), significantly increased the % of spikes produced in bursts in 60% of presumed serotonergic neurons in the anesthetized rat. We confirm here this observation by demonstrating that UCL1684 significantly increased the production of doublets in 17 out of 25 serotonergic neurons. In order to explore whether a GABAergic input was involved in this effect, additional experiments were performed in the presence of the specific GABAA antagonist SR 95531. In these conditions, 50 % (5 out of 10) of serotonergic neurons showed an increase in the production of doublets when UCL 1684 was applied (p = 0.31 vs control), suggesting that a GABAergic input is not implicated in the regulation of the firing pattern of 5-HT neurons by the SK blocker. Finally, the effect of SK channel blockade was explored in vitro in slices. Bath application of the SK blocker apamin (300 nM) did not induce bursting in 15 out of 18 neurons (p < 0.001 vs in vivo control conditions), although it did increase the coefficient of variation of the interspike intervals.Taken together, our results suggest that SK blockade induces burst firing in a majority of dorsal raphe serotonergic neurons. This effect does not involve GABAergic interneurons, but requires an input that is only present in vivo. [less ▲]Detailed reference viewed: 7 (1 ULg) Direct inhibition of the DNA-binding activity of POU transcription factors Pit-1 and Brn-3 by selective binding of a phenyl-furan-benzimidazole dication.Peixoto, Paul ; Liu, Yang; Depauw, Sabine et alin Nucleic Acids Research (2008), 36(10), 3341-53The development of small molecules to control gene expression could be the spearhead of future-targeted therapeutic approaches in multiple pathologies. Among heterocyclic dications developed with this aim ... [more ▼]The development of small molecules to control gene expression could be the spearhead of future-targeted therapeutic approaches in multiple pathologies. Among heterocyclic dications developed with this aim, a phenyl-furan-benzimidazole dication DB293 binds AT-rich sites as a monomer and 5'-ATGA sequence as a stacked dimer, both in the minor groove. Here, we used a protein/DNA array approach to evaluate the ability of DB293 to specifically inhibit transcription factors DNA-binding in a single-step, competitive mode. DB293 inhibits two POU-domain transcription factors Pit-1 and Brn-3 but not IRF-1, despite the presence of an ATGA and AT-rich sites within all three consensus sequences. EMSA, DNase I footprinting and surface-plasmon-resonance experiments determined the precise binding site, affinity and stoichiometry of DB293 interaction to the consensus targets. Binding of DB293 occurred as a cooperative dimer on the ATGA part of Brn-3 site but as two monomers on AT-rich sites of IRF-1 sequence. For Pit-1 site, ATGA or AT-rich mutated sequences identified the contribution of both sites for DB293 recognition. In conclusion, DB293 is a strong inhibitor of two POU-domain transcription factors through a cooperative binding to ATGA. These findings are the first to show that heterocyclic dications can inhibit major groove transcription factors and they open the door to the control of transcription factors activity by those compounds. [less ▲]Detailed reference viewed: 13 (2 ULg) A direct link between growth retardation and inflammation? Identification of a splice site mutation in the bovine RNF11 geneSartelet, Arnaud ; Fasquelle, Corinne ; Tamma, Nico et alin New Biotechnology (2010, April 27), (supplement 1), 63Detailed reference viewed: 18 (1 ULg) Direct measurement of static chest wall compliance in unsedated calvesDesmecht, Daniel ; Rollin, Frédéric ; Amory, Hélène et alin Proceedings of the 8th Comparative Respiratory Society Meeting (1989)Detailed reference viewed: 5 (0 ULg) Direct measurements of interactions between hydrophobically anchored strongly charged polyelectrolyte brushesAbraham, T.; Giasson, S.; Gohy, Jean-François et alin Langmuir (2000), 16(9), 4286-4292We investigated the nature and the range of interactions between negatively charged polyelectrolyte-coated surfaces as a function of salt concentration using the surface forces apparatus. The measured ... [more ▼]We investigated the nature and the range of interactions between negatively charged polyelectrolyte-coated surfaces as a function of salt concentration using the surface forces apparatus. The measured force profiles (interaction forces versus separation distance) are purely repulsive and show long-range electrostatic and short-range steric interactions. The measured range of interaction in salt-free as well as in low ionic strengths extends well beyond the contour length of the polyelectrolyte chain. It is shown that the interaction range between the ionic brush layers and the grafting density depend on the ionic strength of the solution. In salt-free solution, the counterions associated with polyelectrolyte cause the chains to stretch and give rise to long-range double-layer electrostatic repulsions between the opposing chains. When salt is added to the system, the electrostatic interactions are partially screened and the polymer chain regains its flexibility and therefore the range of interactions is reduced. The measured total range of interaction exhibits relatively weaker dependence on the salt concentration. We find that our force−distance profiles with added salt in a compressed regime can be very well described by the Pincus scaling model. [less ▲]Detailed reference viewed: 19 (1 ULg) Direct Modelling of Unit Operations on Molecular LevelBabic, D; Pfennig, Andreas Conference (2006)Detailed reference viewed: 1 (0 ULg)