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Hepatobiliary & Pancreatic Diseases International 2003年第2期2卷 486-495页

作者： magalij.fontaine the Department of Pathology and Laboratory Medicine Medical University of South Carolina. Charleston SC 29425 USA

OBJECTIVE: To review the current progress of islet cell transplantation in patients with insulin-dependent diabetes, emphasizing on the difficulties with recovering and preserving islet cell mass and function, 30% of which is lost during the peri-transplantation period. RESULTS: The islet-cell isolation technique is perfected, but improvements are still progressing in two major directions: preservation of islet cells and tolerance induction. Optimum islet cell viability and function depends on appropriate revascularization of the islet graft and blockade of thrombus formation as well as cytokine and free radical release. Conditioning the islet cells in-vitro prior to transplantation to either upregulate VEGF expression or downregulate NF-kappa B transcription factor has proven to improve revascularization and to prevent islet cell apoptosis and cytokine-mediated damage. Tolerance induction is currently being best achieved by selecting and combining immunosuppressive agents such as monoclonal antibodies which target the major signaling molecules during immune activation, but which are least toxic to islet cells. CONCLUSIONS: Patients with insulin-dependent diabetes will greatly benefit from current developments in effective approaches to protect islets during the peritransplant period. Emerging interest in stem cell biology and differentiation may provide the ultimate solution to the problem of organ scarcity and islet cell protection from the peritransplant induced damage.

关键词： islets of Langerhans transplantation graft function graft preservation type I diabetes

Free-standing microscale photonic lantern spatial mode(De-)multiplexer fabricated using 3D nanoprinting

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Light(Science & Applications) 2024年第6期13卷 1170-1185页

作者： Yoav Dana Yehudit Garcia Aleksei Kukin Lauren Dallachiesa Sterenn Guerrier Nicolas K.fontaine Dan M.Marom Institute of Applied Physics Hebrew University of JerusalemJerusalemIsrael Nokia Bell Labs 600 Mountain AveNew ProvidenceNJ07974USA

Photonic lantern(PL)spatial multiplexers show great promise for a range of applications,such as future high-capacity mode division multiplexing(MDM)optical communication networks and free-space optical *** enable efficient conversion between multiple single-mode(SM)sources and a multimode(MM)waveguide of the same *** multiplexers operate by facilitating adiabatic transitions between the SM arrayed space and the single MM ***,current fabrication methods are forcing the size of these devices to multi-millimeters,making integration with micro-scale photonic systems quite *** advent of 3D micro and nano printing techniques enables the fabrication of freestanding photonic structures with a high refractive index contrast(photopolymer-air).In this work we present the design,fabrication,and characterization of a 6-mode mixing,375µm long PL that enables the conversion between six single-mode inputs and a single six-mode *** PL was designed using a genetic algorithm based inverse design approach and fabricated directly on a 7-core fiber using a commercial two-photon polymerization-based 3D printer and a *** the waveguides exhibit high index contrast,low insertion loss(−2.6 dB),polarization dependent(−0.2 dB)and mode dependent loss(−4.4 dB)were measured.

关键词： mode enable printing

Python Server Page Performance Analysis and Modeling

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Communications and Network 2024年第1期16卷 1-30页

作者： Razafindraibe Marolahy Alix Randrianomenjanahary Lala Ferdinand Rafamantanantsoa fontaine Mahatody Thomas F. Angelo Raherinirina University of Fianarantsoa Fianarantsoa Madagascar

Today, in the field of computer networks, new services have been developed on the Internet or intranets, including the mail server, database management, sounds, videos and the web server itself Apache. The number of solutions for this server is therefore growing continuously, these services are becoming more and more complex and expensive, without being able to fulfill the needs of the users. The absence of benchmarks for websites with dynamic content is the major obstacle to research in this area. These users place high demands on the speed of access to information on the Internet. This is why the performance of the web server is critically important. Several factors influence performance, such as server execution speed, network saturation on the internet or intranet, increased response time, and throughputs. By measuring these factors, we propose a performance evaluation strategy for servers that allows us to determine the actual performance of different servers in terms of user satisfaction. Furthermore, we identified performance characteristics such as throughput, resource utilization, and response time of a system through measurement and modeling by simulation. Finally, we present a simple queue model of an Apache web server, which reasonably represents the behavior of a saturated web server using the Simulink model in Matlab (Matrix Laboratory) and also incorporates sporadic incoming traffic. We obtain server performance metrics such as average response time and throughput through simulations. Compared to other models, our model is conceptually straightforward. The model has been validated through measurements and simulations during the tests that we conducted.

关键词： Performance Analysis Queue Performance Model Web Server Internet World Wide Web Web Server Performance

Regulating electronic structure of porous nickel nitride nanosheet arrays by cerium doping for energy-saving hydrogen production

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Nano Research 2023年第2期16卷 2543-2550页

作者： Rui-Qing Li Suyuan Zeng Bin Sang Chaozhuang Xue Konggang Qu Yu Zhang Wei Zhang Guangyu Zhang Xinghui Liu Jie Deng Olivier fontaine Yachao Zhu School of Textile and Clothing Nantong UniversityNantong 226019China School of Chemistry and Chemical Engineering Shandong Provincial Key Laboratory/Collaborative Innovation Center of Chemical Energy Storage and Novel Cell TechnologyLiaocheng UniversityLiaocheng 252059China Department of Chemistry Sungkyunkwan UniversityJangan-GuSuwon 16419Republic of Korea Institute for Advanced Study&College of Food and Biological Engineering Chengdu UniversityChengdu 610106China Molecular Electrochemistry for Energy laboratory VISTECRayong 21210Thailand Institut Universitaire de France 75005 ParisFrance ICGM Universitéde MontpellierCNRS34293 MontpellierFrance

Water electrolysis for energy-efficient H_(2)production coupled with hydrazine oxidation reaction(HzOR)is prevailing,while the sluggish electrocatalysts are strongly hindering its scalable ***,we schemed a novel porous Ce-doped Ni3N nanosheet arrays grown on nickel foam(Ce-Ni3N/NF)as a remarkable bifunctional catalyst for both hydrogen evolution reaction and ***,the overall hydrazine splitting system can achieve low cell voltages of 0.156 and 0.671 V at 10 and 400 mA·cm^(−2),and the system is remarkably stable to operate over 100 h continuous test at the high-current-density of 400 mA·cm^(−2).Various characterizations prove that the porous nanosheet arrays expose more active sites,and more excellent diffusion kinetics and lower charge-transfer resistance,therefore boosting catalytic ***,density functional theory calculation reveals that the incorporation of Ce can effectively optimize the free energy of hydrogen adsorption and promote intrinsic catalytic activity of Ni_(3)N.

关键词： electrocatalysis cerium doping hydrogen evolution reaction hydrazine oxidation reaction adsorption free energy

Temperature modifies activity, inter-individual relationships and group structure in a fish

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Current Zoology 2017年第2期63卷 175-183页

作者： Tatiana COLCHEN Fabrice TELETCHEA Pascal fontaine Alain PASQUET Université de Lorraine Unité de Recherche Animal et Fonctionnalités des Produits Animaux USC INRA 340 F-54506 Vandceuvre-Iès-Nancy Cedex 09 France CNRS (National Center for Scientific Research) Délégation Régionale Centre Est. 17 Rue Notre Dame des Pauvres F-54500 Vandceuvre-Iès-Nancy France

A host of abiotic factors modify fish social behavior. However, few studies have characterized the effects of temperature on behavior. In this study, brown trout fry were reared at 5 different temperatures (4°C, 6°C, 8°C, 10°C, and 12°C). In order to characterize group structure, 3 behavioral parameters were investigated: group social structure (based on inter-individual distances), inter-individual relationships (based on physical contacts), and individual activity. These behavioral parameters were studied at the emergence stage, which corresponds to a switch from a social gregarious life in the gravel to a solitary one in the water column. Data analysis showed that the inter-individual distances increased with increasing temperature, particularly the nearest neighbor distance. The mean number of physical contacts between fry increased at both low and high temperatures. At high temperatures, most fry moved apart from each other after a physical contact. Swimming activity decreased at both the lower and upper temperatures (18% of activity at 4°C, 38% at 8°C, and 12% at 12°C). This study showed that temperature modifies brown trout fry activity, inter-individual relationships, and social behavior, which all affect group cohesion before emergence and can influence their survival and dispersal.

关键词： early development emergence freshwater species group structure relationships

Assessment of the Effects of Supplemental Rumen Protected B Vitamins and Choline for Periparturient Cows: A Meta-Analysis of 28 Feeding Studies

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Open Journal of Animal Sciences 2023年第1期13卷 151-165页

作者： Essi Evans Emilie fontaine Ousama AlZahal Chris Gwyn E + E Technical Advisory Services Bowmanville Canada Jefo Nutrition Inc. Saint-Hyacinthe Canada AlZahal Innovation and Nutrition Kitchener Canada

There are currently no prescribed requirements for B vitamins or choline for dairy cows during the transition period, but many recent studies have shown a variety of benefits from supplying these nutrients to periparturient cows. The purpose of this research effort was to determine the potential benefit of including a rumen protected blend composed of B vitamins (riboflavin, folic acid, vitamin B12) and choline (RPBlend, Jefo Nutrition Inc., St. Hyacinthe, QC, Canada) for dairy cows during the transition period, based on results from 28 on-farm feeding studies (USA-12, Mexico-7, Canada-4, Chile-3, Australia-1, Brazil-1) conducted between 2011 and 2018. All farms participated in monthly herd management record keeping systems and were selected to participate in studies due to their excellent management. Meta-analyses in which risk differences were determined were used to assess the effects of the supplemental RPBlend on health parameters and reproduction. The effect size was used as the determinant of the possible contribution of RPblend on the yields of milk, energy corrected milk (ECM), fat and protein yields during the first four weeks of lactation. Results showed that the inclusion of RPblend reduced (P 0.10) with the inclusion of the BPBlend. The incidence rate of subclinical ketosis, determined as blood beta hydroxy butyric acid greater than 1.2 mM was lower (P (than those not supplemented. The proportion of cows confirmed pregnant by 100 days in milk was greater for cows given the BPBlend (P 0.10) while the yield of milk protein was greater (P

关键词： Lactating Dairy Cows Transition Period Rumen Protection B Vitamins Choline

Ag-Based Catalysts in Different Supports: Activity for Formaldehyde Oxidation

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Advances in Materials Physics and Chemistry 2022年第8期12卷 163-176页

作者： Rached Ousji Zouhaier Ksibi Abdelhamid Ghorbel Céline fontaine Laboratory of Materials Chemistry and Catalysis Faculty of Sciences of Tunis University of Tunis El Manar Tunis Tunisia Institute of Chemistry of Poitiers: Materials and Natural Resources (IC2MP) University of Poitiers Poitiers France

Through the impregnation method, Ag catalysts with different support (such as TiO2 and γ-Al2O3) were prepared and then tested for catalytic oxidation of formaldehyde (HCHO) at low temperatures. The Ag/TiO2 catalyst exhibited strong catalytic performance, converting HCHO to CO2 and H2O at around 95°C. However, the Ag/Al2O3 catalysts showed much lower activity and reached 100% conversion at 125°C. The Ag-based catalysts were next characterized by several methods (XRD, TEM, FT-R, BET and H2-TPR). Results of characterization revealed that support dramatically impacts the size and dispersion of Ag particles. The XRD analysis showed the existence of different peaks of the silver on the surface of Al2O3 in the contrast with TiO2 no specific peaks exist. Therefore, the size of the Ag particles and their dispersion are the most important factors that affect their catalytic performance for formaldehyde oxidation. In terms of catalytic performance for HCHO oxidation, the Ag/TiO2 catalyst possesses the best Ag dispersion, as well as the smallest Ag particle size.

关键词： Formaldehyde Oxidation TiO2 Al2O3 Silver (Ag) Impregnation Sol-Gel

Spatial evolution of friction of a textured wafer surface

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Friction 2013年第1期1卷 92-97页

作者： Huaping XIAO Ke WANG Grant FOX Michel BELIN Julien fontaine Hong LIANG Mechanical Engineering Texas A&M UniversityCollege StationTexas 77843USA Materials Science and Engineering Texas A&M UniversityCollege StationTexas 77843USA Ecole Centrale de Lyon/CNRS-UMR 5513 France

Mechanical failure of integrated circuits and micro-electro-mechanical systems(MEMS)demands new understanding of friction in small *** present research,we demonstrated an in situ approach to measure sliding friction of a patterned surface composing multi-materials and *** effects of materials and surface morphology on friction and electrical contact resistance were *** material transfer at the interface of dissimilar materials was found to play dominating roles in *** current work provides important insights from the fundamentals of friction that benefit the design of new micro-devices.

关键词： micro-electro-mechanical systems(MEMS) patterned wafers friction transfer wear electrical contact resistance

Pharmacological manipulation of transcription factor protein-protein interactions:opportunities and obstacles

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Cell Regeneration 2015年第1期4卷 8-19页

作者： Frank fontaine Jeroen Overman Mathias François Division of Genomics of Development and Diseases Institute for Molecular BioscienceThe University of Queensland306 Carmody RoadSt LuciaQLD 4072Australia

Much research on transcription factor biology and their genetic pathways has been undertaken over the last30 years, especially in the field of developmental biology and cancer. Yet, very little is known about the molecularmodalities of highly dynamic interactions between transcription factors, genomic DNA, and protein *** breakthroughs such as RNA-seq (RNA-sequencing), ChIP-seq (chromatin immunoprecipitationsequencing), RIME (rapid immunoprecipitation mass spectrometry of endogenous proteins), and single-moleculeimaging will dramatically accelerate the discovery rate of their molecular mode of action in the next few *** a pharmacological viewpoint, conventional methods used to target transcription factor activity withmolecules mimicking endogenous ligands fail to achieve high specificity and are limited by a lack of identificationof new molecular targets. Protein-protein interactions are likely to represent one of the next major classes oftherapeutic targets. Transcription factors, known to act mostly via protein-protein interaction, may well be atthe forefront of this type of drug development. One hurdle in this field remains the difficulty to collate structuraldata into meaningful information for rational drug design. Another hurdle is the lack of chemical libraries meeting thestructural requirements of protein-protein interaction *** more attempts at modulating transcription factor activity are undertaken, valuable knowledge will be accumulatedon the modality of action required to modulate transcription and how these findings can be applied to developingtranscription factor drugs. Key discoveries will spawn into new therapeutic approaches not only as anticancer targetsbut also for other indications, such as those with an inflammatory component including neurodegenerative disorders,diabetes, and chronic liver and kidney diseases.

关键词： Transcription Screening Proteomics Interactome Pharmacology Specificity Cancer Genomics

Scalable non-mode selective Hermite–Gaussian mode multiplexer based on multi-plane light conversion

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Photonics Research 2021年第2期9卷 88-97页

作者： HE WEN YUANHANG ZHANG RACHEL SAMPSON NICOLAS K.fontaine NING WANG SHENGLI FAN GUIFANG LI The College of Optics&Photonics University of Central FloridaOrlandoFlorida 32816-2700USA Bell Laboratories Alcatel-LucentHolmdelNew Jersey 07733USA

Non-mode-selective(NMS) multiplexers(muxes) are highly desirable for coherent power combining to produce a high-power beam with a shaped profile(wavefront synthesis) from discrete, phase-locked emitters. We propose a design for a multi-plane light conversion(MPLC)-based NMS mux, which requires only a few phase masks for coherently combining hundreds of discrete input beams into an output beam consisting of hundreds of Hermite–Gaussian(HG) modes. The combination of HG modes as a base can further construct a beam with arbitrary wavefront. The low number of phase masks is attributed to the identical zero-crossing structure of the Hadamard-coded input arrays and of the output HG modes, enabling the practicality of such devices. An NMS mux supporting 256 HG modes is designed using only seven phase masks, and achieves an insertion loss of-1.6 d B, mode-dependent loss of 4.7 d B, and average total mode crosstalk of-4.4 d B. Additionally, this design,featuring equal power for all input beams, enables phase-only control in coherent power combining, resulting in significant simplifications and fast convergence compared with phase-and-amplitude control.

关键词： mode coherent hundreds