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The epididymal immune balance:a key to preserving male fertility

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Asian Journal of Andrology 2019年第6期21卷 531-539页

作者： Allison Voisin fabrice saez Joel R Drevet Rachel Guiton Team Mechanisms of Posttesticular Infertility GReD LaboratoryCNRS UMR 6293-INSERM U1103 University of Clermont Auvergne Clermont-Ferrand 63001France

Up to 15%of male in fertility has an immuno logical origi n,either due to repetitive infections or to autoimmune resp on ses mainly affecting the epididymis,prostate,and *** observations and epidemiological data clearly contradict the idea that the testis confers immune protection to the whole male genital *** a consequenee,the epididymis,in which posttesticular spermatozoa mature and are stored,has raised some in terest in recent years when it comes to its immune mecha *** deed,sperm cells are produced at puberty,long after the establishment of self-toleranee,and they possess unique surface proteins that cannot be recognized as *** are potential targets of the immune system,with the risk of inducing autoantibodies and consequently male *** immunity is based on a finely tuned equilibrium between efficient immune responses to pathogens and strong tolerance to sperm *** processes rely on incompletely described molecules and cell *** review compiles recent studies focusing on the immune cell types populating the epididymis,and proposes hypothetical models of the organization of epididymal immunity with a special emphasis on the immune response,while also discussing important aspects of the epididymal immune regulation such as tolerance and tumour control.

关键词： epididymis immune response lymphocytes mononuclear phagocytes toleranee

Posttesticular sperm maturation, infertility, and hypercholesterolemia

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Asian Journal of Andrology 2015年第5期17卷 742-748,I0007页

作者： Marjorie Whitfield Xavier PoUet-Villard Rachel Levy Joel R Drevet fabrice saez Team 'Mechanisms of post-testicular infertility' Genetique Reproduction et Developpement UMR CNRS 6293 INSERM U1103 Clermont Universite 24 Avenue des Landais BP80026 63171 Aubiere Codex France Service d'Histologie-Embryologie-Cytogenetique-CECOS Hopital Jean Verdier (AP-HP) Avenue du 14 Juillet 93143 Bondy France Service de Medecine de la Reproduction Hopital Tenon (AP-HP) 4 Rue de la Chine 75020 Paris France Unite de Recherche en Epidemiologie Nutritionnelle INSERM U557 INRA CNAM Universite Paris 13 CRNH IdF 93017 Bobigny France

Cholesterol is a key molecule in the mammalian physiology of especial particular importance for the reproductive system as it is the common precursor for steroid hormone synthesis. Cholesterol is also a recognized modulator of sperm functions, not only at the level of gametogenesis. Cholesterol homeostasis regulation is crucial for posttesticular sperm maturation, and imbalanced cholesterol levels may particularly affect these posttesticular events. Metabolic lipid disorders （dyslipidemia） affect male fertility but are most of the time studied from the angle of endocrine/testicular consequences. This review will focus on the deleterious effects of a particular dyslipidemia, Le., hypercholesterolemia, on posttesticular maturation of mammalian spermatozoa.

关键词： cholesterol dyslipidemia epididymis fertility posttesticular maturation spermatozoa

Liver X receptors and epididymal epithelium physiology

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Asian Journal of Andrology 2007年第4期9卷 574-582页

作者： fabrice saez Eléore Chabory Rémi Cadet Patrick Vernet Silvère Baron2 Jean-Marc A. Lobaccaro Joeol R. Drevet Laboratoire Epididyme et Maturation des Gamètes and Centre de Recherche en Nutrition Humaine d＇Auvergne Université Blaise Pascal CNRS UMR 6547 Aubiere Cedex 63177 France Laboratoire de Physiologie Cellulaire et d＇Endocrinologie Moléculaire and Centre de Recherche en Nutrition Humaine d＇Auvergne Université Blaise Pascal CNRS UMR 6547 Aubiere Cedex 63177 France

Aim： To investigate the roles of liver X receptors （LXR） in the lipid composition and gene expression regulation in the murine caput epididymidis. LXR are nuclear receptors for oxysterols, molecules derived from cholesterol metabolism that are present in mammals as two isoforms： LXRα, which is more specifically expressed in lipid-metabolising tissues, such as liver, adipose and steroidogenic tissues, and macrophages, whereas LXRβ is ubiquitous. Their importance in reproductive physiology has been sustained by the fact that male mice in which the function of both LXR has been disrupted have fertility disturbances starting at the age of 5 months, leading to complete sterility by the age of 9 months. These defects are associated with epididymal epithelial degeneration in caput segments one and two, and with a sperm midpiece fragility, leading to the presence of isolated sperm heads and flagella when luminal contents are recovered from the cauda epididymidis. Methods： The lipid composition of the caput epididymidis of wild-type and LXR-deficient mice was assessed using oil red O staining on tissue cryosections and lipid extraction followed by high performance liquid chromatography or gas chromatography. Gene expression was checked by quantitative real time polymerase chain reaction. Results： Using LXR-deficient mice, we showed an alteration of the lipid composition of the caput epididymidis as well as a significantly decreased expression of the genes encoding SREBPlc, SCD1 and SCD2, involved in fatty acid metabolism. Conclusion： Altogether, these results show that LXR are important regulators of epididymal function, and play a critical role in the lipid maturation processes occurring during sperm epididymal maturation. （Asian J Androl 2007 July; 9： 574-582）

关键词： epididymis liver X receptors nuclear receptors lipids cholesterol gene expression

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)

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