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Antimalarial activity of the aqueous extract of Euphorbia cordifolia Elliot in Plasmodium berghei-infected mice

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Asian Pacific Journal of Tropical Medicine 2020年第4期13卷 176-184页

作者： Raceline Gounoue Kamkumo Jaures Marius Tsakem Nangap Lauve Rachel Tchokouaha Yamthe FlorenceNgueguim Tsofack Patrick Valère Tsouh fokou Mariscal Brice Tchatat Tali Théophile Dimo fabrice FekamBoyom Department of Animal Biology and Physiology University of Yaounde 1Cameroon Institute of Medical Research and Medicinal Plant Studies YaoundeCameroon Department of Biochemistry University of Yaounde 1Cameroon

Objective:To evaluate the antimalarial activity of the aqueous extract of Euphorbia(E.)cordifolia Elliot against Plasmodium(P.)berghei-infected ***:Thirty healthy Swiss mice were intraperitoneally inoculated with 200μL of *** parasitized-erythrocytes and divided into five groups,and then daily treated for 5 d with single dose of 10 mL/kg of distilled water for malaria control,10 mg/kg of chloroquine for the chloroquine control and 100,200 and 400 mg/kg of the aqueous extract of *** for the three test *** was monitored by *** the end of the treatment,animals were sacrificed,and blood was collected for haematological and biochemical *** were collected for biochemical and histopathological *** significance(P<0.05)was evaluated by analysis of variance followed by the Tukey post-test using Graphpad prism ***:*** extract decreased the parasite load to 2.46%,with an effective dose(ED50)of 113.07 mg/kg compared to the malaria group where the parasite load increased to(46.46±10.28)%.*** extract prevented hypoglycaemia,anaemia,leucocytosis and thrombocytopenia,attenuated the increase of transaminases activities,bilirubin and creatinine rate,and improved catalase and superoxide dismutase activities,while reducing malondialdehyde contents in the liver and *** extract significantly prevented histological damages observed in the malaria control *** acute toxicity sign was observed in mice with plant extract at the dose up to 5000 mg/***:*** extract at 200 and 400 mg/kg showed significant antimalarial *** results support its traditional use in the treatment of malaria.

关键词： Antimalarial activity Curative effects Euphorbia cordifolia Plasmodium berghei

On the Motion Law of Fronts for Scalar Reaction-Diffusion Equations with Equal Depth Multiple-Well Potentials

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Chinese Annals of Mathematics,Series B 2017年第1期38卷 83-148页

作者： fabrice BETHUEL Didier SMETS UPMC-Paris6 UMR 7598 LJLLParisF-75005France

Slow motion for scalar Allen-Cahn type equation is a well-known phenomenon,precise motion law for the dynamics of fronts having been established first using the socalled geometric approach inspired from central manifold theory(see the results of Carr and Pego in 1989). In this paper, the authors present an alternate approach to recover the motion law, and extend it to the case of multiple wells. This method is based on the localized energy identity, and is therefore, at least conceptually, simpler to implement. It also allows to handle collisions and rough initial data.

关键词： Reaction-diffusion systems Parabolic equations Singular limits

Risk Information Sources for Snow Disaster Risk Preparedness in Scotland

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International Journal of Disaster Risk Science 2021年第6期12卷 854-866页

作者： Josephine Adekola fabrice Renaud Carol Hill Adam Smith Business School University of GlasgowGlasgow G128QQ.UK School of Interdisciplinary Studies.University of Glasgow.Dumfries DG14ZL UK

Heavy snow disruptions are common and costly occurrences in the UK,including ***,heavy snow remains an underresearched aspect of disaster risks in *** study critically examined the 2018 heavy snow event in Scotland referred to as the“Beast from the East”(BfE)in order to explore the different sources of information used by the public in preparation for and response to heavy snow *** study also examined the effectiveness of BfE risk communication between authorities and the public and sought to determine if there is a relationship between risk information received and the intention to mitigate *** were collected through a semistructured survey from(n=180)residents of the Annandale and Eskdale region of Dumfries and Galloway,*** analysis shows that public authority information sources were the most sought-after information sources,followed by online and web *** found statistically significant differences between groups(such as age,gender,and mobility/disability)in terms of using risk information *** analysis shows that the relationship between information received and the intention to mitigate risks is not linear but influenced by intervening variables such as work pressures,financial commitment,and stakeholders’*** argue that where full adherence to official risk advice is required,policymakers should carefully consider issues around these three factors.

关键词： Disaster preparedness Heavy snow Risk information sources Risk perception Scotland

Plasmonics of regular shape particles,a simple group theory approach

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Nano Research 2020年第6期13卷 1597-1603页

作者： Sarra Mitiche Sylvie Marguet fabrice Charra Ludovic Douillard Université Paris-Saclay CEACNRSSPECF-91191Gif sur YvetteFrance Université Paris-Saclay CEACNRSNIMBEF-91191Gif sur YvetteFrance

A simple hand calculation method based on group theory is proposed to predict the near field maps of finite metallic nanoparticles(MNP)of canonical geometries:prism,cube,hexagon,disk,sphere,*** to low order localized surface plasmon resonance *** this article,we report the principles of the group theory approach and demonstrate,through several examples,the general character of the group theory method which can be applied to describe the plasmonic response of particles of finite or infinite symmetry point *** validation is achieved by collection of high-resolution subwavelength near-field maps by photoemission electron microscopy(PEEM)on a representative set of Au colloidal particles exhibiting either finite(hexagon)or infinite(disk,sphere)symmetry point groups.

关键词： surface plasmon resonance group theory hexagon disk sphere photoemission electron microscopy(PEEM)

Epididymis cholesterol homeostasis and sperm fertilizing ability

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Asian Journal of Andrology 2011年第1期13卷 11-17页

作者： fabrice Saez Ouvrier and Joel R Drevet UMR GReD CNRS 6247 INSERM U931 Clermont Universite Equipe ＇Epididyme et maturation des gametes＇ Aubiere cedex 63171 France

Cholesterol, being the starting point of steroid hormone synthesis, is a long known modulator of both female and male reproductive physiology especially at the level of the gonads and the impact cholesterol has on gametogenesis. Less is known about the effects cholesterol homeostasis may have on postgonadic reproductive functions. Lately, several data have been reported showing how imbalanced cholesterol levels may particularly affect the post-testicular events of sperm maturation that lead to fully fertile male gametes. This review will focus on that aspect and essentially centers on how cholesterol is important for the physiology of the mammalian epididymis and spermatozoa.

关键词： cholesterol homeostasis epididymosomes fertility post-testicular maturation spermatozoa

High Capacity Spectrum Sensing Framework Based on Relay Cooperation

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China Communications 2016年第8期13卷 117-126页

作者： Wu Xuanli Han Xingling fabrice Labeau School of Electronic and Information Engineering Harbin Institute of Technology Harbin 150001 China Department of Electrical and Computer Engineering McGill University Quebec Canada

In order to reduce interference to primary users and provide better performance of detection probability and channel capacity in multi-user cooperative spectrum sensing networks, a high capacity spectrum sensing framework is proposed based on the analysis of amplification factors on the performance of detection probability and channel capacity. Thanks to the energy concentration property of chirp signals in the Fractional Fourier Transform(Fr FT) domain, sinusoidal signal and different chirp signals are utilized for primary user and cognitive users, respectively. Hence, spectrum sensing and signal transmission can be performed simultaneously in our proposed framework. Simulation results show that compared with the previous relay-based framework, the modified cooperative spectrum sensing framework can improve the detection probability significantly, and the channel capacity can also be improved. Moreover, the amplification factor can be used to realize the tradeoff between detection probability and channel capacity in our proposed framework.

关键词： cognitive radio cooperative spectrum sensing energy detection detection probability channel capacity

The biosorption of Cr（VI） ions by dried biomass obtained from a chromium-resistant bacterium

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Frontiers of Chemical Science and Engineering 2014年第4期8卷 454-464页

作者： Paul fabrice NGUEMA Zejiao LUO Jingjing LIAN State Key Laboratory of Biogeology and Environmental Geology Ministry of Education (BGEG) School of Environmental Studies China University of Geosciences Wuhan 430074 China Schools of Earth Environment and Water Resources Yangtze University Wuhan 430100 China

The biosorption potential of many different kinds of biomaterials has been widely studied. However, there is little data on the biosorption mechanism of Cr（VI） by dried biomass. So the bio-removal of Cr（VI） ions from aqueous solutions was investigated using dried biomass from a chromium-resistant bacterium. The bacterium was isolated from dewatered sludge samples that were obtained from a sewage treatment plant. Equilibrium and kinetic experiments were performed at different metal concentra- tions, pH values, and biosorbents dosages. The biomass was characterized using scanning electron microscopy and energy-dispersive X-ray spectroscopy. The functional groups in the Bacillus cereus biomass which may play a role in the biosorption process were identified by Fourier transform infrared spectroscopy. The biosorption process was found to be highly pH dependent and the optimum pH for the adsorption of Cr（VI） was 2.0：k0.3 at 30-4-2 ℃. The experimental data fit well with Langmuir and Freundlich models as well as a pseudo-second order kinetic model. The mechanism for the biosorption was also studied by fitting the kinetic data with an intra-particle diffusion model and a Boyd plot. External mass transfer was found to be the rate-determining step for the adsorption process. Biosorption could be an alternative mechanism besides bio-oxidation and bio-reduction for the bioremediation of heavy metals.

关键词： Bacillus cereus Pf-1 biosorption capacity,biosorbents Cr(VI) biomass

On the use of 1g physical models for ground movements and soil-structure interaction problems

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Journal of Rock Mechanics and Geotechnical Engineering 2020年第1期12卷 197-211页

作者： Marwan Al Heib fabrice Emeriault Huu-Luyen Nghiem INERIS Parc technologique AlataVemeuil-En-HalatteF-60550France Universite Grenoble Alpes 3SRGrenobleF-38000France CNRS 3SRGrenobleF-38000France

The paper focusses on the use of physical modelling in ground movements(induced by underground cavity collapse or mining/tunnelling)and associated soil-structure interaction *** paper presents first an overview of using 1 g physical models to solve geotechnical problems and soil-structure interactions related to vertical ground *** the lg physical modelling application is illustrated to study the development of damage in masonry structure due to subsidence and cavity collapse.A largescale 1 g physical model with a 6 m^3 container and 15 electric jacks is presented with the use of a threedimensional(3D)image correlation *** influence of structure position on the subsidence trough is analysed in terms of crack density and damage *** obtained results can improve the methodology and practice for evaluation of damage in masonry ***,ideal physical model is difficult to ***,future improvement of physical models(analogue materials and instrumentation)could provide new opportunities for using 1 g physical models in geotechnical and soilstructure applications and research projects.

关键词： Subsidence Physical modelling Geotechnical problems Soil-structure interaction

Estimation of the Lyman-α signal of the EFILE diagnostic under static or radiofrequency electric field in vacuum

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Plasma Science and Technology 2018年第7期20卷 1-6页

作者： Carlo POGGI Theo GUILLAUME fabrice DOVEIL Laurence CHIERIGIER-KOVACIC Consorzio RFX Corso Stati UnitiI-35127 PadovaItaly Aix-Marseille Universite CNRSPIIM UMR 7345F-13397 Marseille Cedex 20France

The electric field induced Lyman-a emission diagnostic aims to provide a non intrusive and precise measurement of the electric field in plasma, using a beam of hydrogen atoms prepared in the metastable 2s state. The metastable particles are obtained by means of a proton beam extracted from a hydrogen plasma source, and neutralised by interaction with vaporised caesium. When a 2s atom enters a region where an electric field is present, it undergoes a transition to the 2p state （Stark mixing）. It then quickly decays to the ground level, emitting Lyman-a radiation, which is collected by a photomultiplier. The 2s → 2p transition rate is proportional to the square of the magnitude of the electric field, and depends on the field oscillation frequency （with peaks around l GHz）. By measuring the intensity of the Lyman-a radiation emitted by the beam it is possible to determine the magnitude of the field in a defined region. In this work, an analysis of the behaviour of the diagnostic under static or radiofrequency electric field is presented. Electric field simulations obtained with a finite element solver of Maxwell equations, combined with theoretical calculations of the Stark mixing transition rate, are used to develop a model for the interpretation of photomultiplier data. This method shows good agreement with experimental results for the static field case, and allows to measure the field magnitude for the oscillating case.

关键词： electric field measurement electromagnetic simulations Stark effect plasma diagnostics