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 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 67881 to 67900 of 107953     3390 3391 3392 3393 3394 3395 3396 3397 3398 3399 3400     A multiwavelength investigation of the massive eclipsing binary Cyg OB2 #5Linder, Natacha ; Rauw, Grégor ; Manfroid, Jean et alin Astronomy and Astrophysics (2009), 495Context. The properties of the early-type binary Cyg OB2 #5 have been debated for many years and spectroscopic and photometric investigations yielded conflicting results. Aims. We have attempted to ... [more ▼]Context. The properties of the early-type binary Cyg OB2 #5 have been debated for many years and spectroscopic and photometric investigations yielded conflicting results. Aims. We have attempted to constrain the physical properties of the binary by collecting new optical and X-ray observations. Methods. The optical light curves obtained with narrow-band continuum and line-bearing filters are analysed and compared. Optical spectra are used to map the location of the He II $\lambda$ 4686 and H$\alpha$ line-emission regions in velocity space. New XMM-Newton as well as archive X-ray spectra are analysed to search for variability and constrain the properties of the hot plasma in this system. Results. We find that the orbital period of the system slowly changes though we are unable to discriminate between several possible explanations of this trend. The best fit solution of the continuum light curve reveals a contact configuration with the secondary star being significantly brighter and hotter on its leading side facing the primary. The mean temperature of the secondary star turns out to be only slightly lower than that of the primary, whilst the bolometric luminosity ratio is found to be 3.1. The solution of the light curve yields a distance of $925 \pm 25$ pc much lower than the usually assumed distance of the Cyg OB2 association. Whilst we confirm the existence of episodes of higher X-ray fluxes, the data reveal no phase-locked modulation with the 6.6 day period of the eclipsing binary nor any clear relation between the X-ray flux and the 6.7 yr radio cycle. Conclusions. The bright region of the secondary star is probably heated by energy transfer in a common envelope in this contact binary system as well as by the collision with the primary's wind. The existence of a common photosphere probably also explains the odd mass-luminosity relation of the stars in this system. Most of the X-ray, non-thermal radio, and possibly $\gamma$-ray emission of Cyg OB2 #5 is likely to arise from the interaction of the combined wind of the eclipsing binary with at least one additional star of this multiple system. [less ▲]Detailed reference viewed: 51 (10 ULg) Multiwavelength Observations of Gamma-ray Binary CandidatesMcSwain, M.V.; Chernyakova, M.; Malishev, D. et alin 2012 Fermi Symposium proceedings - eConf C121028 (2012, October)There are currently only six known high mass X-­‐ray binaries (HMXBs) that also exhibit MeV, GeV, and/or TeV emission ("gamma-­‐ray binaries"). Expanding the sample of gamma-­‐ray binaries and identifying ... [more ▼]There are currently only six known high mass X-­‐ray binaries (HMXBs) that also exhibit MeV, GeV, and/or TeV emission ("gamma-­‐ray binaries"). Expanding the sample of gamma-­‐ray binaries and identifying unknown Fermi sources are currently of great interest to the community. Based upon their positional coincidence with the unidentified Fermi sources 1FGL J1127.7-­‐6244c and 1FGL J1808.5-­‐1954c, the Be stars HD 99771 and HD 165783 have been proposed as gamma-­‐ray binary candidates. During Fermi Cycle 4, we have performed multiwavelength observations of these sources using XMM-­‐Newton and the CTIO 1.5m telescope. We do not confirm high energy emission from the Be stars. Here we examine other X-­‐ray sources in the X-­‐ray sources in the field of view that are potential counterparts to the Fermi sources. [less ▲]Detailed reference viewed: 12 (3 ULg) MULTIWAVELENGTH OBSERVATIONS OF THE RUNAWAY BINARY HD 15137McSwain, M. V.; De Becker, Michaël ; Roberts, M. S. E. et alin Astronomical Journal (The) (2010), 139HD 15137 is an intriguing runaway O-type binary system that offers a rare opportunity to explore the mechanism by which it was ejected from the open cluster of its birth. Here, we present recent blue ... [more ▼]HD 15137 is an intriguing runaway O-type binary system that offers a rare opportunity to explore the mechanism by which it was ejected from the open cluster of its birth. Here, we present recent blue optical spectra of HD 15137 and derive a new orbital solution for the spectroscopic binary and physical parameters of the O star primary. We also present the first XMM-Newton observations of the system. Fits of the EPIC spectra indicate soft, thermal X-ray emission consistent with an isolated O star. Upper limits on the undetected hard X-ray emission place limits on the emission from a proposed compact companion in the system, and we rule out a quiescent neutron star (NS) in the propeller regime or a weakly accreting NS. An unevolved secondary companion is also not detected in our optical spectra of the binary, and it is difficult to conclude that a gravitational interaction could have ejected this runaway binary with a low mass optical star. HD 15137 may contain an elusive NS in the ejector regime or a quiescent black hole with conditions unfavorable for accretion at the time of our observations. [less ▲]Detailed reference viewed: 17 (6 ULg) The multiwavelength picture of star formation in the very young open cluster NGC6383Rauw, Grégor ; De Becker, Michaël in Reipurth, Bo (Ed.) Handbook of Star Forming Region. Volume 2: The Southern Sky (2008)We review the properties of the very young (˜ 2 Myr) open cluster NGC 6383. The cluster is dominated by the massive binary HD 159176 (O7 V + O7 V). The distance to NGC 6383 is consistently found to be 1.3 ... [more ▼]We review the properties of the very young (˜ 2 Myr) open cluster NGC 6383. The cluster is dominated by the massive binary HD 159176 (O7 V + O7 V). The distance to NGC 6383 is consistently found to be 1.3 ± 0.1 kpc and the average reddening is determined to be E(bv) = 0.32 ± 0.02. Several pre-main sequence candidates have been identified using different criteria relying on the detection of emission lines, infrared excesses, photometric variability and X-ray emission. [less ▲]Detailed reference viewed: 11 (1 ULg) The multiwavelength picture of the open cluster Westerlund 2 and the very massive binary WR20aNazé, Yaël ; Rauw, Grégor Poster (2007)Detailed reference viewed: 2 (0 ULg) A Multiwavelength Study of the Runaway Binaries HD 14633 and HD 15137McSwain, M Virginia; De Becker, Michaël ; Roberts, Mallory S E et alin Bulletin de la Societe Royale des Sciences de Liege (2011), 80The runaway O-type binaries HD 14633 and HD 15137 were likely ejected from the cluster of their birth by supernovae explosions in close binaries. Here we present recent optical spectra to update the ... [more ▼]The runaway O-type binaries HD 14633 and HD 15137 were likely ejected from the cluster of their birth by supernovae explosions in close binaries. Here we present recent optical spectra to update the orbital solutions of the binaries and study the physical parameters of the O star primaries. We also present XMM-Newton observations of both systems that attempt to detect hard power-law emission from compact companions. EPIC spectra of HD 14633 at periastron and apastron reveal a non-thermal X-ray flux component that is variable during the orbit. Our EPIC spectra of HD 15137 indicate thermal X-ray emission consistent with an isolated O star. We provide an upper limit on the emission from a compact companion in HD 15137. [less ▲]Detailed reference viewed: 10 (0 ULg) The multiwavelength view of hot, massive starsRauw, Grégor ; De Becker, Michaël ; Nazé, Yaël et alin Bulletin de la Société Royale des Sciences de Liège (2011), 80Massive stars are certainly among the most fascinating objects of stellar populations. They trigger many astrophysical processes from star formation to the chemical enrichment of the interstellar medium ... [more ▼]Massive stars are certainly among the most fascinating objects of stellar populations. They trigger many astrophysical processes from star formation to the chemical enrichment of the interstellar medium. Yet, their properties are still not fully understood and these objects are therefore at the core of many ongoing research activities. With the advent of new, high-performance, ground-based and space-borne facilities, the multi-wavelength investigation of hot, massive stars has definitely been boosted over the last decade. It is indeed nowadays possible to study these objects over a wide part of the electromagnetic spectrum, all the way from radio waves to gamma-rays. Motivated by this fact, we decided to organize a conference devoted to this topic in the framework of the well-established series of Liege International Astrophysical Colloquia (LIAC). The resonance in the community was extremely positive, with many proposals for high-quality contributions. During the week of 12 - 16 July 2010, 138 astrophysicists, from institutes in 21 countries all over the world, gathered in Liege to discuss how the multi-wavelength approach has revolutionized their research on massive stars. The colloquium was organized into five thematic sessions, and the present proceedings are organized along the same chapters: (1) stellar winds, diagnostics across the electromagnetic spectrum; (2) massive star formation, confronting theory and observation; (3) evolution and interaction of massive stars with their environment; (4) future instrumentation and its application to massive star research; (5) massive binaries: interaction and evolution. [less ▲]Detailed reference viewed: 44 (24 ULg) Multiyear homing and fidelity to residence areas by individual barbel (Barbus barbus)Ovidio, Michaël ; Parkinson, Denis; Philippart, Jean-Claude et alin Belgian Journal of Zoology (2007), 137(2), 183-190Nine barbels (Barbus barbus) from the River Ourthe (River Meuse basin) were equipped with transmitters programmed to switch ON during two consecutive spawning seasons in 1998 and 1999 (April to July). Six ... [more ▼]Nine barbels (Barbus barbus) from the River Ourthe (River Meuse basin) were equipped with transmitters programmed to switch ON during two consecutive spawning seasons in 1998 and 1999 (April to July). Six of the nine barbels tracked in 1998 were also tracked in 1999 during the same period. The length of the spawning migration ranged from 200 to 22700m. After the spawning activity observed from 12-16 May 1998 and 4-6 May 1999, the barbels homed to the site occupied before spawning. Each barbel used the same spawning area in 1998 and 1999, despite the presence of other spawning sites on their migratory route. These observations revealed the existence of strict reproductive homing in the barbel and a long-term fidelity to particular resting places. [less ▲]Detailed reference viewed: 98 (23 ULg) Multiyear infrared solar spectroscopic measurements of HCN, CO, C2H6,and C2H2 tropospheric columns above Lauder, New Zealand (45 degrees S latitude)Rinsland, Curtis P.; Jones, Nicholas B.; Connor, Brian J. et alin Journal of Geophysical Research. Atmospheres (2002), 107(D14), [1] Near-simultaneous, 0.0035 or 0.007 cm(-1) resolution infrared solar absorption spectra of tropospheric HCN, C2H2, CO, and C2H6 have been recorded from the Network for the Detection of Stratospheric ... [more ▼][1] Near-simultaneous, 0.0035 or 0.007 cm(-1) resolution infrared solar absorption spectra of tropospheric HCN, C2H2, CO, and C2H6 have been recorded from the Network for the Detection of Stratospheric Change station in Lauder, New Zealand (45.04degreesS, 169.68degreesE, 0.37 km altitude). All four molecules were measured on over 350 days with HCN and C2H2 reported for the first time based on a new analysis procedure that significantly increases the effective signal-to-noise of weak tropospheric absorption features in the measured spectra. The CO measurements extend by 2.5 years a database of measurements begun in January 1994 for CO with improved sensitivity in the lower and middle troposphere. The C2H6 measurements lengthen a time series begun in July 1993 with peak sensitivity in the upper troposphere. Retrievals of all four molecules were obtained with an algorithm based on the semiempirical application of the Rodgers optimal estimation technique. Columns are reported for the 0.37- to 12-km-altitude region, approximately the troposphere above the station. The seasonal cycles of all four molecules are asymmetric, with minima in March-June and sharp peaks and increased variability during August-November, which corresponds to the period of maximum biomass burning near the end of the Southern Hemisphere tropical dry season. Except for a possible HCN column decrease, no evidence was found for a statistically significant long-term trend. [less ▲]Detailed reference viewed: 34 (16 ULg) A Multi­‐Scale Computer Model of the Cardiovascular System Can Account for the Three Roles of the Left AtriumPironet, Antoine ; Dauby, Pierre ; Kosta, Sarah et alin Abstract Book GIGA-Day (2013, January 28)Detailed reference viewed: 50 (11 ULg) A Multi­‐Scale Computer Model of the Cardiovascular System Can Account for the Three Roles of the Left AtriumPironet, Antoine ; Dauby, Pierre ; Kosta, Sarah et alPoster (2013, January 28)Detailed reference viewed: 28 (12 ULg) Multi‐scale modelling of fibre reinforced composite with non‐local damage variableWu, Ling ; Noels, Ludovic ; Adam, Laurent et alConference (2011, July)Classical finite element simulations face the problems of losing uniqueness and strain localization when the strain softening of materials is involved. Thus, when using continuum damage model or ... [more ▼]Classical finite element simulations face the problems of losing uniqueness and strain localization when the strain softening of materials is involved. Thus, when using continuum damage model or plasticity softening model, numerical convergence will not be obtained with the refinement of the finite element discretization when strain localization occurs. Gradient-enhanced softening and non-local continua models have been proposed by several researchers in order to solve this problem. In such approaches, the spatial gradients of state variables are incorporated in the macroscopic constitutive equation [1, 2]. However, when dealing with complex heterogeneous materials, a direct simulation of the macroscopic structures is unreachable, motivating the development of non-local homogenization schemes [3]. In our work, a gradient-enhanced homogenization procedure is proposed for fiber reinforced materials. In the approach, the fiber is assumed to remain linear elastic while the matrix material is modeled as elasto-plastic [4] coupled with damage and is described by a non-local constitutive model [5]. Toward this end, the mean-field homogenization is based on the knowledge of the macroscopic deformation tensors, internal variables and their gradients, which are applied to a micro-structural representative volume element (RVE). Macro-stress is then obtained from a homogenization process. This procedure is applied to simulate damage process occurring in unidirectional carbon-fiber reinforced epoxy composites submitted to different loading histories. [less ▲]Detailed reference viewed: 12 (1 ULg) Multi‐spectral simultaneous observations of Saturn's aurorae in Jan. 2009Lamy, L.; Prange, R.; Gustin, Jacques et alConference (2012)Detailed reference viewed: 8 (3 ULg) Multy-year cycles observed in air temperature data and proxy seriesMabille, Georges ; Nicolay, Samuel in European Physical Journal. Special Topics (2009), 174First, palaeoclimatic time series are analyzed under the lens of the continuous wavelet transform. Two cycles, of period 30 and 43 months respectively, are detected in millennial temperature ... [more ▼]First, palaeoclimatic time series are analyzed under the lens of the continuous wavelet transform. Two cycles, of period 30 and 43 months respectively, are detected in millennial temperature reconstructions. These rhythms correspond to the ones detected in weather station temperature records in a previous study of the authors. It is then showed that most parts of the globe are aﬀected by at least one of the two cycles. Their relationship with the main climatic indices is also investigated, as well as the statistical signiﬁcance of the observations. [less ▲]Detailed reference viewed: 24 (9 ULg) "Der Mund entsteht mit dem Schrei". Die Signifikationen des Körpers und seine Medialisierung bei Heiner MüllerKüpper, Achim in Peter Weiss Jahrbuch (2004), 13Detailed reference viewed: 19 (0 ULg) El mundo asociativo de la emigración española a Europa : situaciones actuales y perspectivas de futuroMolina Marmol, Maïté ; Tur, BrunoReport (2009)Detailed reference viewed: 25 (0 ULg) El mundo sobre el papel. El impacto de la escritura y la lectura en la estructura del conocimientoOlson, David R.; Willson, Patricia Book published by Editorial Gedisa (1999)Detailed reference viewed: 52 (2 ULg) MUNE in the last 30 years: what can we expect of it in practice?WANG, François-Charles ; GERARD, Pascale ; BOUQUIAUX, Olivier in Correspondances en Nerf & Muscle (2004)Detailed reference viewed: 6 (2 ULg) Munkoyo : des racines comme sources potentielles en enzymes amylolytiques et une boisson fermentée traditionnelle (synthèse bibliographique)Foma, Roland Kibwega; Destain, Jacqueline ; Kayisu, Kalenga et alin Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2013), 17(2), 352-363Detailed reference viewed: 17 (4 ULg) Le Munkoyo : une source d'amylases végétales pour une boisson fermentée traditionnelleFoma Kibwega, Roland Doctoral thesis (2013)In Africa, several sources of amylases are not well documented. Munkoyo roots are used as the source of amylases during the traditional preparation of a fermented beverage called munkoyo. These roots are ... [more ▼]In Africa, several sources of amylases are not well documented. Munkoyo roots are used as the source of amylases during the traditional preparation of a fermented beverage called munkoyo. These roots are unique as the synthesis and accumulation of amylases activities do not require germination. Despite this advantage, munkoyo roots are not well known as sources of amylases and they have not yet been introduced into industrial processes. Thus, the aim of this PhD project was to (1) promote munkoyo roots as sources of α- and β-amylases and to (2) propose pathways of optimization and industrialization of manufacturing munkoyo beverage. In the first part, purification, characterization and identification of α- and β-amylases from munkoyo roots was achieved. Amylases from roots of Eminia holubii, Eminia harmsiana, Rhynchosia insignis insignis and Rhynchosia insignis affinis were retained in our study. Compared to malted cereals, α- and β-amylases from munkoyo roots are more thermostable and their activities are optimal at high temperatures. However, these properties are closer to those of germinated cotyledons belonging to some Fabaceae family plants. Using LC-ESI MSMS analysis, this study showed significant matching of α- and β-amylases from munkoyo roots to germinated leguminous seeds. In the second part, the traditional production of munkoyo beverage was studied. The evolution of physicochemical parameters and ferments involved in spontaneous fermentation was investigated. Acidification is promoted by thermophilic and heterofermentative lactic acid bacteria. Alcohol production in munkoyo is due mainly to Saccharomyces cerevisiae. The study shows that knowledge of amylase properties and the use of an appropriate microbial starter will optimize the manufacturing process and the quality of munkoyo beverage. [less ▲]Detailed reference viewed: 63 (18 ULg)