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World Journal of Traditional chinese Medicine 2015年第4期1卷 103-104页

作者： Habib Toukourou Amoussatou Sakirigui georges c.accrombessi Joёlle Quetin-Leclercq Jacques H.Poupaert Fernand A.Gbaguidi Medicinal Organic chemistry Laboratory Benin Center of Ecological Drug Discovery School of pharmacy/ UAC Laboratoire de chimie Organique Physique et de Synthese UAC Pharmacognosy Louvain Drug Research Institute UCL Medicinal chemistry Louvain Drug Research InstituteUCL Laboratoire de chimie Organique Physique et de Synthese

Introduction:Tuberculosis,caused by Mycobacterium tuberculosis became more prevalent due to drug *** citratus,a crop from the African flora contains an essential oil rich in carbonyl *** of carbonyl compounds with thi... 详细信息

关键词： Gc ANTIMIcROBIAL AcTIVITY OF cYMBOPOGON cITRATUS ESSENTIAL OIL AND cITRAL THIOSEMIcARBAZONE AGAINST MYcOBAcTERIUM TUBERcULOSIS

A discrete-time susceptible-infectious-recovered-susceptible model for the analysis of influenza data

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Infectious Disease Modelling 2023年第2期8卷 471-483页

作者： georges Bucyibaruta c.B.Dean Mahmoud Torabi Department of Statistics and Actuarial Science University of Waterloo200 University Ave WWaterlooONN2L 3G1Canada Department of community Health Sciences University of ManitobaWinnipegManitobaR3E 0W3Canada

We develop a discrete time compartmental model to describe the spread of seasonal influenza *** time and disease state variables are assumed to be discrete,this model is considered to be a discrete time,stochastic,Susceptible-Infectious-RecoveredSusceptible(DT-SIRS)model,where weekly counts of disease are assumed to follow a Poisson *** allow the disease transmission rate to also vary over time,and the disease can only be reintroduced after extinction if there is a contact with infected individuals from other host *** capture the variability of influenza activities from one season to the next,we define the seasonality with a 4-week period effect that may change over *** examine three different transmission rates and compare their performance to that of existing *** though there is limited information for susceptible and recovered individuals,we demonstrate that the simple models for transmission rates effectively capture the behaviour of the disease *** use a Bayesian approach for *** framework is applied in an analysis of the temporal spread of influenza in the province of Manitoba,canada,2012e2015.

关键词： Discrete-time epidemic model Infectious diseases Influx process Non-linear stochastic dynamics Seasonal influenza SIRS model Transmission parameter

EFFEcT OF A PROPELLER AND GAS DIFFUSION ON BUBBLE NUcLEI DISTRIBUTION IN A LIQUID

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Journal of Hydrodynamics 2012年第6期24卷 809-822页

作者： HSIAO chao-Tsung cHAHINE georges L. DYNAFLOW INC.

A multi-bubble dynamics code accounting for gas diffusion in the liquid and through the bubble wall was developed and used to study the modification of a bubble nuclei population dynamics by a propeller. The propeller flow field was obtained using a Reynolds-Averaged Navier-Stokes （RANS） solver and bubble nuclei populations were propagated in this field. The numerical procedure enabled establishment of the possibility of production behind the propeller of relatively large visible bubbles starting from typical ocean nuclei size distributions. The resulting larger bubbles are seen to cluster in the blade wakes and tip vortices. Parametric investigations of the initial nuclei size distribution, the dissolved gas concentration, and the cavitation number were conducted to ide- ntify their effects on bubble entrainment and the resultant void fractions and bubble distribution modifications downstream from the propeller. Imposed synthetic turbulence-like fluctuations unto the average RANS flow field were also used to study the effect averaging in the RANS procedure has on the results.

关键词： gas diffusion bubble entrainment propeller

Do aphids actively search for ant partners？

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Insect Science 2015年第2期22卷 283-288页

作者： christophe Y. Fischer Maryse Vanderplanck georges c. Lognay claire Detrain Francois J. Verheggen Laboratory of Analytical chemistry University of Liege Gembloux Agro-Bio Tech Gembloux Research Institute of Biosciences Laboratory of Zoology University of Mons Mons Unit of Social Ecology Universit6 Libre de Bruxelles Brussels Department of Functional and Evolutionary Entomology University of Liege Gembloux Agro-Bio Tech Gembloux Belgium

The aphid-ant mutnalistic relationships are not necessarily obligate for neither partners but evidence is that such interactions provide them strong advantages in terms of global fitness. While it is largely assumed that ants actively search for their mutualistic partners namely using volatile cues; whether winged aphids （i.e., aphids＇ most mobile form） are able to select ant-frequented areas had not been investigated so far. Ant-frequented sites would indeed offer several advantages for these aphids including a lower predation pressure through ant presence and enhanced chances of establishing mutuaslistic interactions with neighbor ant colonies. In the field, aphid colonies are often observed in higher densities around ant nests, which is probably linked to a better survival ensured by ants＇ services. Nevertheless, this could also result from a preferential establishment of winged aphids in ant-frequented areas. We tested this last hypothesis through different ethological assays and show that the facultative myrmecophilous black bean aphid, Aphisfabae L., does not orientate its search for a host plant preferentially toward ant-frequented plants. However, our results suggest that ants reduce the number of winged aphids leaving the newly colonized plant. Thus, ants involved in facultative myrmecophilous interactions with aphids appear to contribute to structure aphid populations in the field by ensuring a better establishment and survival of newly established colonies rather than by inducing a deliberate plant selection by aphid partners based on the proximity of ant colonies.

关键词： ant aphid Aphisfabae Lasius niger mutualism partner research

AQUEOUS STABLE FREE RADIcAL POLYMERIZATION PROcESSES

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chinese Journal of Polymer Science 2004年第4期22卷 309-312页

作者： Andrea R. Szkurhan Michael K. georges University of Toronto at Mississauga 3359 Mississauga Road North South Building Mississauga Ontario L5L 1C6University of Toronto at Mississauga 3359 Mississauga Road North South Building Mississauga Ontario L5L 1C6

An overview of aqueous polymerizations, which include emulsion, miniemulsion and suspension polymerizations, under stable free radical polymerization (SFRP) conditions is presented. The success of miniemulsion and suspension SFRP polymerizations is contrasted with the difficulties associated with obtaining a stable emulsion polymerization. A recently developed unique microprecipitation technique is referenced as a means of making submicron sized particles that can be used to achieve a stable emulsion SFRP process.

关键词： Stable free radical polymerization Living-radical polymerization Aqueous polymerization Miniemulsion polymerization Emulsion polymerization Suspension polymerization

Hepatitis c virus infection:are there still specific problems with genotype 3?

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World Journal of Gastroenterology 2015年第42期21卷 12101-12113页

作者： claire Gondeau georges Philippe Pageaux Dominique Larrey Department of Hepato-gastroenterology A Hospital Saint Eloi INSERM U1183 Institute of Regenerative Medicine and Biotherapy University of Montpellier

Hepatitis c virus(HcV) infection is one of the most common causes of chronic liver disease and the main indication for liver transplantation worldwide. As promising specific treatments have been introduced for genotype 1, clinicians and researchers are now focusing on patients infected by non-genotype 1 HcV, particularly genotype 3. Indeed, in the golden era of direct-acting antiviral drugs, genotype 3 infections are no longer considered as easy to treat and are associated with higher risk of developing severe liver injuries, such as cirrhosis and hepatocellular carcinoma. Moreover, HcV genotype 3 accounts for 40% of all HcV infections in Asia and is the most frequent genotype among HcV-positive injecting drug users in several countries. Here, we review recent data on HcV genotype 3 infection/treatment, including clinical aspects and the underlying genotype-specific molecular mechanisms.

关键词： Hepatitis c Genotype 3 Direct-acting antivirals In

Bacteria may contribute to distant species recognition in ant-aphid mutualistic relationships

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Insect Science 2017年第2期24卷 278-284页

作者： christophe Y. Fischer claire Detrain Philippe Thonart Eric Haubruge Frederic Francis Francois J. Verheggen georges c. Lognay Laboratory of Analytical chemistry University of Liege Gembloux Agro-Bio Tech Passage des Deportes 2 5030 Gembloux Unit of Social Ecology Universite Libre de Bruxelles CP231 50 avenue F. Roosevelt B-1050 Brussels Walloon center of Industrial Biology University of Liege B40 Sart-Tilman 4000 Liege 4Functional and Evolutionary Entomology University of Liege Gembloux Agro-Bio Tech Passage des Deportes 2 5030 Gembloux Belgium

Mutualistic interactions between ant and aphid species have been the subject of considerable historical and contemporary investigations, the primary benefits being clean- ing and protection for the aphids and carbohydrate-rich honeydew for the ants. Questions remained, however, as to the volatile semiochemical factor influencing this relationship. A recent study highlighted the role of bacterial honeydew volatile compounds in ant at- traction. Here, ant＇s ability to distantly discriminate 2 aphid species was investigated based on bacterial honeydew semiochemicals emissions using a two-way olfactometer. Both the mutualistic aphid Aphis fabae L. and the nonmyrmecophilous aphid Acyrthosiphon pisum Harris were found to be attractive for the ant Lasius niger L. The level of attraction was similar in both assays （control vs. one of the aphid species）. However, when given a choice between these 2 aphid species, ants showed a significant preference for Aphis fabae. Honeydew volatiles, mostly from bacterial origins, are known to be a key element in ant attraction. Using the same olfactometry protocol, the relative attractiveness of volatiles emitted by honeydews collected from each aphid species and by bacteria isolated from each honeydew was investigated. Again, ants significantly preferred volatiles released by Aphis fabae honeydew and bacteria. This information suggests that microbial honeydew volatiles enable ants to distantly discriminate aphid species. These results strengthen the interest of studying the occurrence and potential impact of microorganisms in insect symbioses.

关键词： ant aphid bacteria honeydew mutualism recognition VOc

EXPERIMENTAL AND NUMERIcAL INVESTIGATION OF BUBBLE AUGMENTED WATERJET PROPULSION

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Journal of Hydrodynamics 2012年第5期24卷 635-647页

作者： cHOI Jin-Keun SINGH Sowmitra HSIAO chao-Tsung cHAHINE georges L DYNAFLOW INc. JessupMarylandUSA

This contribution presents experimental and numerical investigations of the concept jet propulsion augmentation using bubble injection. A half-3D （D-shaped cylindrical configuration to enable optimal visualizations） divergent-convergent nozzle was designed, built, and used for extensive experiments under different air injection conditions and thrust measurement schemes. The design, optimization, and analysis were conducted using numerical simulations. The more advanced model was based on a two-way coupling between an Eulerian description of the flow field and a Lagrangian tracking of the injected bubbles using our Surface Averaged Pressure （SAP） model. The numerical results compare very favorably with nozzle experiments and both experiments and simulations validation the thrust augmentation concept. For a properly designed nozzle and air injection system, air injection produces net thrust augmentation, which increases with the rate of bubble injection. Doubling of thrust was measured for a 50% air injection rate. This beneficial effect remains at 50% after account for liquid pump additional work to overcome increased pressure by air injection.

关键词： waterjet propulsion bubble dynamics multi-phase flow

Full-field interferometric imaging of propagating action potentials

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Light(Science & Applications) 2018年第1期7卷 51-61页

作者： Tong Ling Kevin c.Boyle georges Goetz Peng Zhou Yi Quan Felix S.Alfonso Tiffany W.Huang Daniel Palanker Hansen Experimental Physics Laboratory Stanford UniversityStanfordCA 94305USA Department of Ophthalmology Stanford UniversityStanfordCA 94305USA Department of Electrical Engineering Stanford UniversityStanfordCA 94305USA Department of Molecular and cellular Physiology Howard Hughes Medical InstituteStanford UniversityStanfordCA 94305USA Department of chemistry Stanford UniversityStanfordCA 94305USA

currently,cellular action potentials are detected using either electrical recordings or exogenous fluorescent probes that sense the calcium concentration or transmembrane *** imaging has a low temporal resolution,while voltage indicators are vulnerable to phototoxicity,photobleaching,and ***,we report full-field interferometric imaging of individual action potentials by detecting movement across the entire cell *** spike-triggered averaging of movies synchronized with electrical recordings,we demonstrate deformations up to 3 nm(0.9 mrad)during the action potential in spiking HEK-293 cells,with a rise time of *** time course of the optically recorded spikes matches the electrical *** the shot noise limit of the camera(~2 mrad/pix)precludes detection of the action potential in a single frame,for all-optical spike detection,images are acquired at 50 kHz,and 50 frames are binned into 1 ms steps to achieve a sensitivity of 0.3 mrad in a single *** a selfreinforcing sensitivity enhancement algorithm based on iteratively expanding the region of interest for spatial averaging,individual spikes can be detected by matching the previously extracted template of the action potential with the optical *** allows all-optical full-field imaging of the propagating action potentials without exogeneous labels or electrodes.

关键词： action averaging recording

Symbolic generation of the kinematics of multibody systems in EasyDyn: From MuPAD to Xcas/Giac

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Theoretical & Applied Mechanics Letters 2013年第1期3卷 89-94页

作者： Olivier Verlinden Lassaad Ben Fkih georges Kouroussis Department of Theoretical Mechanics Dynamics and Vibrations University of Mons

In the EasyDyn multibody open source project, computer algebra has been used from the beginning to generate the expressions of velocities and accelerations of the bodies, by symbolic differentiation of their position. Originally, the MuPAD computer algebra system had been retained because it was freely available for non commercial purposes and showed very good technical ***, MuPAD is nowadays only available through commercial channels and needs to be replaced to keep EasyDyn publicly available. This paper presents why Xcas/Giac is finally selected,among other long-term promising projects like Axiom, Maxima, Sage or Yacas. Among the choice criteria, the accessibility, the portability, the ease of use, the automatic export to c language, and the similarity with the -MuPAD language are all considered. The performances of the MuPAD and Xcas/Giac implementations are also compared on some examples.c 2013 The chinese Society of Theoretical and Applied Mechanics. [doi：10.1063/2.13013012]

关键词： symbolic multibody systems kinematics computer algebra system open source