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Fingerprint Recognition with Artificial Neural Networks: Application to E-Learning

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Journal of Intelligent Learning Systems and Applications 2016年第2期8卷 39-49页

作者： stephane Kouamo Claude Tangha Department of Computer Science University of Yaounde I Yaounde Cameroon

Fingerprint recognition is a mature biometric technique for identification or authentication application. In this work, we describe a method based on the use of neural network to authenticate people who want to accede to an automated fingerprint system for E-learning. The idea is to apply back propagation algorithm on a multilayer perceptron during the training stage. One of the advantages of this technique is the use of a hidden layer which allows the network to make comparison by calculating probabilities on template which are invariant to translation and rotation. Results come both from the NIST special database 4 and a local database, and show that a proposed method gives good results in some cases.

关键词： Neural Networks Pattern Recognition Fingerprint Back-Propagation E-Learning

Molecular Evolution of the Substrate Specificity of Chloroplastic Aldolases/Rubisco Lysine Methyltransferases in Plants

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Molecular Plant 2016年第4期9卷 569-581页

作者： Sheng Ma Jacqueline Martin-Laffon Morgane Mininno Oceane Gigarel Sabine Brugiere Olivier Bastien Marianne Tardift stephane Ravanel Claude Alban Universite Grenoble Alpes Laboratoire de Physiologie Cellulaire & Vegetale 38041 Grenoble France CNRS UMR5168 38054 Grenoble France CEA iRTSV Laboratoire de Physiologie Cellulaire & Vegetale 38054 Grenoble France INRA USC1359 38054 Grenoble France Universite Grenoble Alpes 38041 Grenoble France CEA iRTSV Biologie & Grande Echelle 38054 Grenoble France INSERM U1038 38054 Grenoble France

Rubisco and fructose-1,6-bisphosphate aldolases （FBAs） are involved in CO2 fixation in chloroplasts. Both enzymes are trimethylated at a specific lysine residue by the chloroplastic protein methyltransferase LSMT. Genes coding LSMT are present in all plant genomes but the methylation status of the substrates varies in a species-specific manner. For example, chloroplastic FBAs are naturally trimethylated in both Pisum sati- vum and Arabidopsis thaliana, whereas the Rubisco large subunit is trimethylated only in the former spe- cies. The in vivo methylation status of aldolases and Rubisco matches the catalytic properties of AtLSMT and PsLSMT, which are able to trimethylate FBAs or FBAs and Rubisco, respectively. Here, we created chimera and site-directed mutants of monofunctional AtLSMT and bifunctional PsLSMT to identify the molecular determinants responsible for substrate specificity. Our results indicate that the His-Ala/Pro- Trp triad located in the central part of LSMT enzymes is the key motif to confer the capacity to trimethylate Rubisco. Two of the critical residues are located on a surface loop outside the methyltransferase catalytic site. We observed a strict correlation between the presence of the triad motif and the in vivo methylation status of Rubisco. The distribution of the motif into a phylogenetic tree further suggests that the ancestral function of LSMT was FBA trimethylation. In a recent event during higher plant evolution, this function evolved in ancestors of Fabaceae, Cucurbitaceae, and Rosaceae to include Rubisco as an additional substrate to the archetypal enzyme. Our study provides insight into mechanisms by which SET-domain protein methyltransferases evolve new substrate specificity.

关键词： SET-domain protein methyltransferase site-directed mutagenesis chimeric enzyme methylation,molecular evolution green lineage

Future Theoretical Approaches in Nuclear Magnetic Resonance

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Journal of Modern Physics 2014年第4期5卷 145-148页

作者： Eugene stephane Mananga Department of Radiology Division of Nuclear Medicine and Molecular Imaging Physics Center for Advanced Medical Imaging Sciences Harvard Medical School and Massachusetts General Hospital Harvard University Boston Massachusetts USA

Solving a time-dependent linear differential equation towards obtaining evolution operators is a central problem in solid-state nuclear magnetic resonance. To this end, average Hamiltonian theory and Floquet theory have been the two commonly used theoretically methods in spin dynamics of NMR. We recently introduced the Floquet-Magnus expansion approach and here, we present the methodology of potentials future theoretical approaches such as the Fer expansion, Chebyshev expansion and Cayley transformation that could be useful tools for numerical integrators and simulations of spin dynamics in NMR.

关键词： Solid-State NMR Average Hamiltonian Theory Floquet Theory Floquet Magnus Theory Fer Expansion

Synthesis of(±)-phthalascidin 622

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Science China Chemistry 2010年第9期53卷 1888-1898页

作者： CHRISTIAN R.Razafindrabe SYLVAIN Aubry BENJAMIN Bourdon MARTA Andriantsiferana stephane Pellet-Rostaing MARC Lemaire Laboratoire de Chimie des Produits Naturels et Biotechnologie(LPNB) Université d'Antananarivo17 Cité Mahatazana-Ampandrianomby101 Antananarivo ICBMS Institut de Chimie et Biochimie Moléculaires et SupramoléculairesCNRSUMR5246Laboratoire de Catalyse et Synthèse Organique ICSM institut de Chimie Séparative de MarcouleCNRS/CEA/UM2/ENSCMUMR 5257Laboratoire de Tri Ionique par des Systèmes Moléculaires auto-assemblés

A synthesis of functionalized phenolic α-amino-alcohols(±)-8 and(±)-16 as synthetic precursors of the catechol tetrahydroisoquinoline structure of phthalascidin 650 was disclosed.(±)-8 was prepared in 5 steps from the commercially available *** from 3-methyl catechol 5,8 steps gave rise to the synthesis of phenolic α-amino-alcohol(±)-16 in 27% overall *** synthetic strategy involved the elaboration of fully functionalized aromatic aldehyde 13 and its transformation into a phenolic α-amino-alcohol(±)-16,through a Knoevenagel condensation,simultaneous reduction of nitroketene and ester functions,and hydrogenolysis of the benzyl protecting *** pentacycle(±)-4 was obtained after 4 additional *** Pictet-Spengler cyclisation between the phenolic α-amino-alcohol(±)-16 and the N-protected α-amino-aldehyde 4 allowed to obtain(1,3')-bis-tetrahydroisoquinoline 17 with N-methylated and N-Fmoc *** last step was a Swern oxidation allowing the expected intramolecular condensation.

关键词： phthalascidin ecteinascidin (1 3’)-bis-tetrahydroisoquinoline Pictet-Spengler Bishler-Napieralsky

Applications of Floquet-Magnus and Fer Expansion Approaches during Cross Polarization Radiation in Solid State NMR

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Journal of Modern Physics 2023年第7期14卷 1136-1156页

作者： Eugene stephane Mananga Thibault Charpentier Program of Physics & Ph. D Program of Chemistry Graduate Center The City University of New York New York NY USA Department of Applied Physics New York University Brooklyn New York USA Department of Engineering Physics and Technology BCC The City University of New York Bronx New York USA CEA IRAMIS Service Interdisciplinaire sur les Systèmes Moléculaires et Matériaux LSDRM UMR CEA/CNRS Gif-sur-Yvette

This paper investigates the concept of Cross Polarization (CP) experiment in addition to revisiting the two potential expansion schemes recently developed in the field of solid-state nuclear magnetic resonance (SSNMR): namely, the Floquet-Magnus expansion and the Fer expansion. We use the aforementioned expansion schemes for the calculation of effective Hamiltonians and propagators when the spin system undergoes Cross Polarization radiation. CP is the gateway experiment into SSNMR. An in-depth comprehension of the underlying mechanics of spin dynamics during the cross-polarization experiment is pivotal for further experimental developments and optimization of more complex solid-state NMR experiments. The main contribution of this work is a prospect related to spin physics;particularly regarding to generalization of the calculation. This work reports original yet interesting novel ideas and developments that include calculations performed on the CP experiment. In fact, the approach presented could play a major role in the interpretation of several fine NMR experiments in solids, which would in turn provide significant new insights in spin physics. The generality of the work points towards potential applications in problems related in solid-state NMR and theoretical developments of spectroscopy as well as interdisciplinary research areas as long as they include spin dynamics concepts.

关键词： Cross Polarization Solid-State NMR Floquet-Magnus Expansion Fer Expansion Spin Dynamics

HACD1,a regulator of membrane composition and fluidity,promotes myoblast fusion and skeletal muscle growth

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分子细胞生物学报:英文版 2015年第5期7卷 429-440页

作者： Jordan Blondelle Yusuke Ohno Vincent Gache stephane Guyot Sebastien Storck Nicolas Blanchard-Gutton Ines Barthelemy Gemma Walmsley Anaelle Rahier Stephanie Gadin Marie Maurer Laurent Guillaud Alexandre Prola Arnaud Ferry Genevieve Aubin-Houzelstein Jean Demarquoy Frederic Relaix Richard JPiercy stephane Blot Akio Kihara Laurent Tiret Fanny Pilot-Storck Inserm IMRB U955-E1094000 CreteilFrance Universite Paris-Est Ecole nationale veterinaire d’Alfort(EnvA)94700 Maisons-AlfortFrance Universite Paris-Est Creteil Faculte de medecine94000 CreteilFrance Laboratory of Biochemistry Faculty of Pharmaceutical SciencesHokkaido UniversitySapporo 060-0812Japan Universite de Bourgogne UMR A 02.102 PAM-EPMBAgroSup Dijon21000 DijonFrance Institut Necker-Enfants Malades INSERM U1151-CNRS UMR 8253Sorbonne Paris CiteUniversite Paris DescartesFaculte de Medecine-Site Broussais75015 ParisFrance Comparative Neuromuscular disease Laboratory Department of Clinical Sciences and ServicesRoyal Veterinary CollegeLondon NW10TUUK Therapie des maladies du muscle strie INSERM U974-CNRS UMR7215-UPMC UM76-Institut de Myologie Universite Pierre et Marie Curie-Universite Paris Descartes75000 ParisFrance Universite de Bourgogne Faculte des Sciences GabrielBio-PeroxIL21000 DijonFrance

The reduced diameter of skeletal myofibres is a hallmark of several congenital myopathies,yet the underlying cellular and molecular mechanisms remain *** this study,we investigate the role of HACD1/PTPLA,which is involved in the elongation of the very long chain fatty acids,in muscle fibre *** humans and dogs,HACD1 deficiency leads to a congenital myopathy with fibre size disproportion associated with a generalized *** of HACD1-deficient Labradors,Hacd1-knockout mice,and Hacd1-deficient myoblasts,we provide evidence that HACD1 promotes myoblast fusion during muscle development and *** further demonstrate that in normal differentiating myoblasts,expression of the catalytically active HACD1 isoform,which is encoded by a muscle-enriched splice variant,yields decreased lysophosphatidylcholine content,a potent inhibitor of myoblast fusion,and increased concentrations of≥C18 and monounsaturated fatty acids of *** lipid modifications correlate with a reduction in plasma membrane *** conclusion,we propose that fusion impairment constitutes a novel,non-exclusive pathological mechanism operating in congenital myopathies and reveal that HACD1 is a key regulator of a lipid-dependent muscle fibre growth mechanism.

关键词： centronuclear myopathy LPC MUFA PTPLA VLCFA

Hepatitis C in Laos： A 7-Year Retrospective Study on 1765 Patients

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Virologica Sinica 2018年第4期33卷 295-303页

作者： Phimpha Paboriboune Thomas Vial Philavanh Sitbounlang stephane Bertani Christian Trepo Paul Deny Francois-Xavier Babin Nicolas Steenkeste Pascal Pineau Eric Deharo Centre d'Infectiologie Lao-Christophe Merieux 3888 Vientiane Laos UMR 152 PHARMADEV IRD Universite de ToulouseUPS 31062 Toulouse France INSERM U1052 CNRS UMR 5286 Cancer Research Centre of Lyon 69008 Lyon France Universite Paris 13 Sorbonne Paris Cite Hopitaux Universitaires Paris Seine Saint Denis 93000 Bobigny France Fondation Merieux 69002 Lyon France INSERM U993 Institut Pasteur Unite 'Organisation Nucleaire et Oncogenese' 75015 Paris France

Hepatitis C virus （HCV） is a global health concern, notably in Southeast Asia, and in Laos the presentation of the HCV- induced liver disease is poorly known. Our objective was thus to describe a comprehensive HCV infection pattern in order to guide national health policies. A study on a group of 1765 patients formerly diagnosed by rapid test in health centres was conducted at the Centre of Infectiology Lao Christophe Merieux in Vientiane. The demographic information of patients, their infection status （viral load： VL）, liver function （aminotransferases） and treatments were analysed. Results showed that gender distribution of infected people was balanced; with median ages of 53.8 for men and 51.6 years for women （13-86 years）. The majority of patients （72%） were confirmed positive （VL 〉 50 IU/mL） and 28% of them had high VL （〉 61oglo）. About 23% of patients had level of aminotransferases indicative of liver damage （〉 40 IU/mL）; but less than 20% of patients received treatment. Patients rarely received a second sampling or medical imaging. The survey also showed that cycloferon, pegylated interferon and ribavirin were the drugs prescribed preferentially by the medical staff, without following any international recommendations schemes. In conclusion, we recommend that a population screening policy and better management of patients should be urgently implemented in the country, respecting official guidelines. However, the cost of biological analysis and treatment are significant barriers that must be removed. Public health resolutions should be immediately enforced in the perspective of meeting the WHO HCV elimination deadline by 2030.

关键词： Hepatitis C virus (HCV) HCV incidence Antiviral agents Laos

三维骨建模系统在人工全膝关节置换时旋转对位的作用

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中国修复重建外科杂志 2008年第1期22卷 12-15页

作者：吴昊 van Driessche stephane Goutallier Daniel 广西壮族自治区人民医院骨科南宁530021 法国亨利蒙多医院矫形与创伤外科

目的为了进行人工全膝关节置换时假体旋转对位的量化研究,探讨三维骨建模的计算机辅助手术系统对量化操作的精确性和有效性。方法2002年11月-2003年6月,采用三维骨建模Ceravision系统对21例21膝保守治疗无效的三间隔骨性关节炎患者行人... 详细信息

目的为了进行人工全膝关节置换时假体旋转对位的量化研究,探讨三维骨建模的计算机辅助手术系统对量化操作的精确性和有效性。方法2002年11月-2003年6月,采用三维骨建模Ceravision系统对21例21膝保守治疗无效的三间隔骨性关节炎患者行人工全膝关节置换术。男5例5膝,女16例16膝;年龄64～79岁,平均72.4岁。左膝10例,右膝11例。主要临床表现为膝关节疼痛和活动受限。病程2～10年。14例膝内翻,7例膝外翻。根据相关的临床体检、影像学和导航系统资料,对术中假体旋转对位量值,并对术后3个月膝关节活动度、膝关节松弛度和髌骨稳定性进行分析。结果全部患者术后切口均Ⅰ期愈合。21例患者均获随访12～16个月,平均13.3个月。术中股骨假体旋转对位内旋1°～外旋5°,胫骨假体旋转对位内旋0°～外旋5°。其中膝内翻患者,股骨假体旋转对位外旋1°～外旋5°,胫骨假体旋转对位外旋2°～外旋5°;膝外翻患者,股骨假体旋转对位内旋1°～外旋4°,胫骨假体旋转对位内旋0°～外旋4°。术后3个月膝关节活动度,最大屈膝度为105～130°,平均115°;膝关节额面松弛度,内侧0.2～0.5cm,平均0.27cm,外侧1.0～2.5cm,平均1.7cm。无膝痛、髌骨失稳和脱位等并发症发生。结论应用三维骨建模的计算机辅助手术系统,可针对患者个体精确地进行假体旋转对位。

关键词：全膝关节置换旋转对位计算机辅助系统三维骨建模

Late-time photometry of two nearby type II-P supernovae: 2004dj and 2004et

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Research in Astronomy and Astrophysics 2009年第7期9卷 783-790页

作者： Tian-Meng Zhang Xiao-Feng Wang Xu Zhou Jun Ma Zhao-Ji Jiang Jiang-Hua Wu Zhen-Yu Wu stephane Basa NationalAstronomicalObservatories Chinese Academy of Sciences Beijing 100012 China Observatoire Astronomique de Marseille-Provence 38 rue Fric Joliot-Curie 13388 Marseille Cedex 13 France Physics Department and Tsinghua Center for Astrophysics （THCA） Tsinghua University Beijing 100084 China Graduate University of Chinese Academy of Sciences Beijing 100049 China Department of Astronomy University of California Berkeley CA 94720-3411 USA

We present late-time photometry for two bright type II-P supernovae （SNe） 2004dj and 2004et, extending over 400 d after the explosion, which are measured with a set of intermediate-band filters that have the advantage of tracing the strength variations of some spectral features. Although these two SNe II-P exhibit similar photometric evolution at earlier times, they diverge during the nebular phase. SN 2004dj shows a slow late-time decline rate with - 0.7 ±0.1 mag （100d）^-1 during the period ranging from t ≈ 200 - 300 d after the explosion, while SN 2004et shows a much faster decline rate at a comparable phase, e.g., 1.3 ± 0.1 mag （100d）^-1. The steeper decay rate seen in SN 2004et is likely due to dust formation in the explosion ejecta. Based on intermediate-band photometry, we derived the evolution of the feature lines [e.g., Hα] of SNe 2004dj and 2004et which are similar in flux at comparable phases but perhaps with significantly different decay rates. The origin of the observed variations in the continuum and the feature lines is briefly discussed.

关键词： supernovae general - supernovae: individual (SN 2004dj SN 2004et) -techniques: photometric