Showing papers by "University of Rouen published in 2009"

A new human immunodeficiency virus derived from gorillas

Abstract: We have identified a new human immunodeficiency virus in a Cameroonian woman. It is closely related to gorilla simian immunodeficiency virus (SIVgor) and shows no evidence of recombination with other HIV-1 lineages. This new virus seems to be the prototype of a new HIV-1 lineage that is distinct from HIV-1 groups M, N and O. We propose to designate it HIV-1 group P.

Simulation of truncated normal variables

Abstract: We provide in this paper simulation algorithms for one-sided and two-sided truncated normal distributions. These algorithms are then used to simulate multivariate normal variables with restricted parameter space for any covariance structure.

Effect of fiber surface modification on the mechanical and water absorption characteristics of sisal/polyester composites fabricated by resin transfer molding

Abstract: Sisal fibers were subjected to various chemical and physical modifications such as mercerization, heating at 100 °C, permanganate treatment, benzoylation and silanization to improve the interfacial bonding with matrix. Composites were prepared by these fibers as reinforcement, using resin transfer molding (RTM). The mechanical properties such as tensile, flexural and impact strength were examined. Mercerized fiber-reinforced composites showed 36% of increase in tensile strength and 53% in Young’s modulus while the permanganate treated fiber-reinforced composites performed 25% increase in flexural strength. However, in the case of impact strength, the treatment has been found to cause a reduction. The water absorption study of these composites at different temperature revealed that it is less for the treated fiber-reinforced composites at all temperatures compared to the untreated one. SEM studies have been used to complement the results emanated from the evaluation of mechanical properties.

2009 version of the Chompret criteria for Li Fraumeni syndrome.

Abstract: in 474FrenchfamiliessuggestiveofLFS,including232familiesfulfillingtheChompret criteria; obtained a mutation detection rate of 29% (67of232families);andestimatedthesensitivityandspecificityoftheChompret criteria to be 82% and 58%, respectively. We also pro-posedextendingtheChompretcriteriatocovertheclinicalpresen-tation of the 82 families in which we identified germline

Human in vivo fluorescence microimaging of the alveolar ducts and sacs during bronchoscopy

Abstract: The aim of the present study was to assess fibred confocal fluorescence microscopy (FCFM) as a tool for imaging the alveolar respiratory system in vivo during bronchoscopy. A 488-nm excitation wavelength FCFM device was used in 41 healthy subjects including 17 active smokers. After topical anaesthesia, the 1.4-mm miniprobe was introduced into the bronchoscope working channel and advanced distally to the alveoli. Morphometric and cellular analyses were performed on selected frames harbouring a minimal compression effect. In vivo acinar microimaging was obtained from each lung segment except for the apical and posterior segments of both upper lobes. Reproducible patterns, corresponding to the elastic framework of the axial and peripheral interstitial systems, were recorded from 192 separate acini. The mean+/-sd thickness of the acinar elastic fibres was 10+/-2.7 microm. Alveolar mouth diameters (mean+/-sd 278+/-53 microm) were normally distributed but appeared smaller in the right upper lobe and right medial basal segment. Lobular microvessels (median diameter 90 microm) were equally distributed throughout the lungs. Alveolar macrophages were not detectable in nonsmokers, whereas a specific tobacco-tar-induced fluorescence was observed in smoking subjects, providing fine details of the alveolar walls and macrophages. A strong correlation was found between the number of cigarettes smoked per day and the amount of large and mobile macrophages observed in vivo, as well as with the intensity of the macrophage alveolitis. Fibred confocal fluorescence microscopy enables accurate exploration of the peripheral lung in vivo in both smokers and nonsmokers.

Microbial inactivation using plasma-activated water obtained by gliding electric discharges.

Abstract: Aim: To evaluate the microbial disinfection efficacy of a plasmachemical solution obtained by the activation of water with gliding electric discharges. Methods and Results: Distilled water was activated for 5 min by a nonthermal quenched plasma of the glidarc type operating in humid air and at atmospheric pressure. The plasma-activated water (PAW) was then used to treat planktonic and adherent cells of Staphylococcus epidermidis, Leuconostoc mesenteroides (as models of Gram-positive bacteria), Hafnia alvei (a Gram-negative bacteria) and Saccharomyces cerevisiae (as a yeast model). The treatments were less efficient on adherent cells than on planktonic cells in the case of bacteria, but not of S. cerevisiae. Inactivation was more effective for bacteria than for the yeast. Conclusions: Significant reductions in microbial populations were achieved in all cases, demonstrating the effectiveness of this new approach to treat contaminated media. Significance and Impact of the Study: PAW is a promising solution with potential application to the decontamination of equipment and surfaces.

Transient co-expression for fast and high-yield production of antibodies with human-like N-glycans in plants.

Abstract: Plant-based transient expression is potentially the most rapid and cost-efficient system for the production of recombinant pharmaceutical proteins, but safety concerns associated with plant-specific N-glycosylation have hampered its adoption as a commercial production system. In this article, we describe an approach based on the simultaneous transient co-expression of an antibody, a suppressor of silencing and a chimaeric human beta1,4-galactosyltransferase targeted for optimal activity to the early secretory pathway in agroinfiltrated Nicotiana benthamiana leaves. This strategy allows fast and high-yield production of antibodies with human-like N-glycans and, more generally, provides solutions to many critical problems posed by the large-scale production of therapeutic and vaccinal proteins, specifically yield, volume and quality.

In Very Young Infants Severity of Acute Bronchiolitis Depends On Carried Viruses

Abstract: Background RT amplification reaction has revealed that various single viruses or viral co-infections caused acute bronchiolitis in infants, and RV appeared to have a growing involvement in early respiratory diseases. Because remaining controversial, the objective was to determine prospectively the respective role of RSV, RV, hMPV and co-infections on the severity of acute bronchiolitis in very young infants.

Fire II Flight Experiment Analysis by Means of a Collisional-Radiative Model

Abstract: DOI: 10.2514/1.39034 We study the behavior of the excited electronic states of atoms in the relaxation zone of one-dimensional airflows obtained in shock-tube facilities. A collisional-radiative model is developed, accounting for thermal nonequilibrium between the translational energy mode of the gas and the vibrational energy mode of individual molecules. The electronic states of atoms are treated as separate species, allowing for non-Boltzmann distributions of their populations. Relaxation of the free-electron energy is also accounted for by using a separate conservation equation. We apply the model to three trajectory points of the Fire II flight experiment. In the rapidly ionizing regime behind strong shock waves, the electronic energy level populations depart from Boltzmann distributions because the highlying bound electronic states are depleted. To quantify the extent of this nonequilibrium effect, we compare the results obtained by means of the collisional-radiative model with those based on Boltzmann distributions. For the earliesttrajectorypoint,weshowthatthequasi-steady-stateassumptionisonlyvalidforthehigh-lyingexcitedstates and cannot be extended to the metastable states.

Direct palladium-catalyzed alkenylation, benzylation and alkylation of ethyl oxazole-4-carboxylate with alkenyl-, benzyl- and alkyl halides.

Abstract: The ethyl oxazole-4-carboxylate was directly and regioselectively alkenylated, benzylated and alkylated with alkenyl-, benzyl-, allyl- and alkyl halides in the presence of catalytic amounts of palladium acetate with caesium carbonate using Buchwald's JohnPhos ligand.

Endoscopic band ligation could decrease recurrent bleeding in Mallory–Weiss syndrome as compared to haemostasis by hemoclips plus epinephrine

Abstract: Summary Background Mallory–Weiss syndrome (MWS) with active bleeding at endoscopy may require endoscopic haemostasis the modalities of which are not well-defined. Aim To compare the efficacy of endoscopic band ligation vs. hemoclip plus epinephrine (adrenaline) in bleeding MWS. Methods From 2001 to 2008, 218 consecutive patients with a MWS at endoscopy were hospitalized in our Gastrointestinal Bleeding Unit. In 56 patients (26%), an endoscopic haemostasis was required because of active bleeding. Band ligation was performed in 29 patients (Banding group), while hemoclip application plus epinephrine injection was performed in 27 patients (H&E group). Treatment efficacy and early recurrent bleeding were retrospectively compared between the two groups. Results Primary endoscopic haemostasis was achieved in all patients. Recurrent bleeding occurred in 0% in Banding group vs. 18% in HE 95% CI = 1.15–15.8) and active bleeding at endoscopy (OR = 1.9; 95% CI = 1.04–5.2) were independent predictive factors of early recurrent bleeding. Conclusions Haemostasis by hemoclips plus epinephrine was an independent predictive factor of rebleeding. This result suggests that band ligation could be the first choice endoscopic treatment for bleeding MWS, but requires further prospective assessment.

Modeling Nonlinear Dynamics and Chaos: A Review

Abstract: This paper reviews the major developments of modeling techniques applied to nonlinear dynamics and chaos. Model representations, parameter estimation techniques, data requirements, and model validation are some of the key topics that are covered in this paper, which surveys slightly over two decades since the pioneering papers on the subject appeared in the literature.

In vitro models of inhalation toxicity and disease. The report of a FRAME workshop.

Abstract: The aim of research in the FRAME Alternatives Laboratory at the University of Nottingham Medical School is summarised, i.e. to use human cell culture-based projects and in vivo studies in human volunteers as alternatives to the use of rodent models in the study of human disease. This is especially important when the available animal models do not adequately represent the pathophysiological situation in humans. The approach is exemplified by summaries of studies on the effects of starvation on skeletal muscle in human volunteers, and on lipid metabolism in obese female volunteers.

Alfa fibres for unsaturated polyester composites reinforcement: Effects of chemical treatments on mechanical and permeation properties

Abstract: In this study, composite materials were prepared using unsaturated polyester resins reinforced by Alfa fibres. The fibres were previously modified by chemical treatments, maleic anhydride (MA), styrene (S), acrylic acid (AA) and acetic anhydride (Ac). The Ac and the S treatments allowed an increase in the moisture resistance and the mechanical properties of the fibres. The preliminary S or MA treatment of the fibres allowed a decrease of the water permeability of the composite. A slight increase of the stiffness of the composite was observed due to the presence of the fibres (treated or not), whereas the resistance (breaking strength and strain) was not improved. The mechanical behaviour of the composites appeared similar whatever the treatment of the fibres except with S treatment which seemed to improve the breaking strength.

Confocal fluorescence endomicroscopy of the human airways.

Abstract: Confocal endomicroscopes aim at providing to the clinician microscopic imaging of a living tissue. The currently available microendoscopic devices use the principle of confocal fluorescent microscopy, in which the objective is replaced by an optical fiber and a miniaturized scanhead at the distal end of the endoscope or by a retractable bundle of optical fibers. Such systems have recently been applied to the explorations of several organs, including the gastrointestinal tract, and more recently to the proximal and distal airways in vivo. Respiratory fluorescence microendoscopes use 488 nm or 660 nm excitation laser light and thin flexible miniprobes that are introduced into the working channel of the bronchoscope. The devices have a lateral resolution of 3 μm, a field of view of 600 μm, and produce real-time imaging at 9 frames per second. For in vivo imaging, the miniprobe is applied onto the bronchial wall surface or advanced into a distal bronchiole down to the acinus. In nonsmokers, the 488-nm excitat...

Influence of Hyperparameters on Random Forest Accuracy

Abstract: In this paper we present our work on the Random Forest (RF) family of classification methods. Our goal is to go one step further in the understanding of RF mechanisms by studying the parametrization of the reference algorithm Forest-RI. In this algorithm, a randomization principle is used during the tree induction process, that randomly selects K features at each node, among which the best split is chosen. The strength of randomization in the tree induction is thus led by the hyperparameter K which plays an important role for building accurate RF classifiers. We have decided to focus our experimental study on this hyperparameter and on its influence on classification accuracy. For that purpose, we have evaluated the Forest-RI algorithm on several machine learning problems and with different settings of K in order to understand the way it acts on RF performance. We show that default values of K traditionally used in the literature are globally near-optimal, except for some cases for which they are all significatively sub-optimal. Thus additional experiments have been led on those datasets, that highlight the crucial role played by feature relevancy in finding the optimal setting of K .

A notational analysis of elite tennis serve and serve-return strategies on slow surface.

Abstract: A notational analysis of singles events at the French Open Grand Slam tournament was undertaken in 2005 and 2006 to characterize the game patterns and strategies of serve and serve-return and to determine their influence on the point issue on a clay court surface. One hundred sixteen men's singles matches were video analyzed. The flat serve (57.6%), particularly down the "T" location (50.3%), allowed servers to win significantly more points than the topspin (24.1%) and slice serves (18.3%). When the topspin was the first serve strategy, servers kept a high percentage of points won from the serve (52.4%). This strategy was essentially used on the second serve (91.6%) by playing the "T" location in the deuce court and the wide zone in the advantage court. Returns to the central zone allowed receivers to win more points (73.3% on first serve and 65.9% on second serve) than plays to external locations. The results highlight the high impact of the first shots of all opponents on the rally. Even on clay, the slowest court surface, serves and serve-returns remain the strokes that most influence the match results in modern tennis games.

Cognitive and non‐cognitive behaviors in an APPswe/PS1 bigenic model of Alzheimer’s disease

Abstract: Neuropsychiatric signs are critical in primary caregiving of Alzheimer patients and yet have been relatively ignored in murine models. In the present study, APPswe/PS1 bigenic mice had higher levels of irritability than non-transgenic controls as measured in the touch escape test. Moreover, APPswe/PS1 mice showed poorer nest building than controls and a higher duration of immobility in the forced swimming assay. These results are concordant with the hypothesis of increased apathy and depression-like behavior in an Alzheimer's disease model. In addition, APPswe/PS1 bigenic mice were deficient in retention of passive avoidance learning and left-right discrimination learning, concordant with previous findings in other Alzheimer-like models.

Thermal response of a field emitter subjected to ultra-fast laser illumination

Abstract: Using an ultra-fast laser assisted atom probe, the temporal evolution of the temperature of a tungsten field emitter subjected to illumination is studied. The combination of pump probe experiments and evaporation rate measurements is used to estimate the duration of field evaporation, the induced peak temperature and the cooling time. The main conclusion of the measurements is that, despite a significant heating of the tip by the laser pulse, the cooling time is anomalously fast, below 0.5 ns. Hence, thermal effects are considered to play a major role in ion emission in contrast to conclusions of our previous works. It is shown that the really fast anomalous cooling rate can only be related to a confined heating zone at the tip apex smaller than the wavelength of the laser.