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Accumulation of Flavonoids in an ntra ntrb Mutant Leads to Tolerance to UV-C

Molecular Plant 2009年第2期2卷 249-258页

作者： Talaat Bashandy Ludivine Taconnat jean-Pierre Renou Yves Meyer jean-Philippe Reichheld Laboratoire Genome et Developpement des Plantes Universite de Perpignan UMR CNRS 5096 52 avenue Paul Alduy 66860 Perpignan France Unite de Recherche en Genomique Vegetale 91057 Evry cedex France

NADPH-dependent thioredoxin reductases （NTRs） are key regulatory enzymes determining the redox state of thioredoxins. There are two genes encoding NTRs （NTRA and NTRB） in the Arabidopsis genome, each encoding a cytosolic and a mitochondrial isoform. A double ntra ntrb mutant has recently been characterized and shows slower plant growth, slightly wrinkled seeds and a remarkable hypersensitivity to buthionine sulfoximine （BSO）, a specific inhibitor of gluta- thione biosynthesis. In this paper, we demonstrate that this mutant also accumulates higher level of flavonoids. Analysis of transcriptome data showed that several genes of the flavonoid pathway are overexpressed in the ntra ntrb mutant. Accumulation of flavonoids is generally considered a hallmark of plant stress. Nevertheless, no elevation of the expression of genes encoding ROS-detoxification enzymes was observed, suggesting that the ntra ntrb plants do not suffer from oxidative disease. Another hypothesis suggests that flavonoids are specifically synthesized in the ntra ntrb mutant in order to rescue the inactivation of NTR. To test this, the ntra ntrb mutant was crossed with transparent testa 4 （tt4） plants with a mutation in the gene encoding the first enzyme in flavonoid biosynthesis. As ntra ntrb plants are more resistant to UV-C treatment than wild-type plants, this higher resistance was abolished in the ntra ntrb tt4 mutant, suggesting that accumulation of flavonoids in the ntra ntrb mutant protects plants against UV-light.

关键词： abiotic/environmental stress oxidative and photo-oxidative stress secondary metabolism - phenylpropanoidsand phenolics gene expression Arabidopsis.

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Rabeprazole test for the diagnosis of gastro-oesophageal reflux disease: Results of a study in a primary care setting

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World Journal of Gastroenterology 2006年第16期12卷 2569-2573页

作者： Stanislas Bruley des Varannes Sylvie Sacher-Huvelin Fabienne Vavasseur Claude Masliah Marc Le Rhun Philippe Aygalenq Sylvie Bonnot-Marlier Yves Lequeux jean paul Galmiche Institut des Maladies de l'Appareil Digestif CIC-INSERM-CHU-44083 NANTES cedexFrance CH Draguignan France Laboratoire JANSSEN-CILAG-1 Avenue Camille Desmoulins -92787 ISSY les MOULINEAUX cedexFrance 4 rue de la Tourelle-44230 SAINT PERE en RETZFrance

AIM： To determine the diagnostic value of the rabeprazole test in patients seen by general practitioners. METHODS： Eighty-three patients with symptoms suggestive of GERD were enrolled by general practitioners in this multi-centre, randomized and doubleblind study. All patients received either rabeprazole （20 mg bid） or a placebo for one week. The diagnosis of GERD was established on the presence of mucosal breaks at endoscopy and/or an abnormal esophageal 24-h pH test. The test was considered to be positive if patients reported at least a ＂clear improvement＂ of symptoms on a 7-point Likert scale. RESULTS： The sensitivities of the test for rabeprazole and the placebo were 83% and 40%, respectively. The corresponding specificity, positive and negative predictive values were 45% and 67%, 71% and 71%, and 62% and 35%, respectively. A receiver operating characteristics （ROC） analysis confirmed that the best discriminatory cut-off corresponded to description of ＂clear improvement＂ CONCLUSION： The poor specificity of the proton-pump inhibitor （PPI） test does not support such an approach to establish a diagnosis of GERD in a primary care setting.

关键词： Gastro-oesophageal reflux disease Diagnostic tool Rabeprazole Proton pump inhibitors Primary care

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嵌入基于案例记忆机制的个人辅助Agent

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计算机科学 2010年第10期37卷 184-189,192页

作者：陈可佳 BARTHES A.jean-paul 南京邮电大学计算技术研究所南京210003 UMR CNRS 6599 HeudiasycUniversité de Technologie de Compiègne

个人辅助agent是一种能够帮助用户解决工作环境中特定任务的认知agent。为个人辅助agent设计了一种记忆机制,用于表示和组织个人辅助agent的记忆。受基于案例推理思想的启发,构建了一个记忆处理器,以对记忆进行更新和管理。在多agent平... 详细信息

个人辅助agent是一种能够帮助用户解决工作环境中特定任务的认知agent。为个人辅助agent设计了一种记忆机制,用于表示和组织个人辅助agent的记忆。受基于案例推理思想的启发,构建了一个记忆处理器,以对记忆进行更新和管理。在多agent平台——OMAS中实现了个人辅助agent原型系统。实验表明,具有记忆机制的个人辅助agent能更有效地执行用户任务。

关键词：辅助agent 基于案例的推理记忆组织包

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小鼠胚胎干细胞磁标记并磁共振成像的研究

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中华医学杂志 2007年第23期87卷 1646-1648页

作者：王蓓 Marisa JACONI 黎健王雁 jean-paul VALLE 卫生部北京医院急诊科北京100730 日内瓦大学附属医院老年医学研究所

目的应用超顺磁氧化铁(SPIO)标记小鼠胚胎干细胞(ESC),并行磁共振成像,为心肌细胞移植体内示踪作初步准备。方法小鼠 ESC 及其分化的心肌细胞与 SPIO 孵育后行电镜分析、细胞内铁含量测定、[Ca^(2+)]共聚焦测定和 MR 成像。结果铁颗粒... 详细信息

目的应用超顺磁氧化铁(SPIO)标记小鼠胚胎干细胞(ESC),并行磁共振成像,为心肌细胞移植体内示踪作初步准备。方法小鼠 ESC 及其分化的心肌细胞与 SPIO 孵育后行电镜分析、细胞内铁含量测定、[Ca^(2+)]共聚焦测定和 MR 成像。结果铁颗粒分布在胞质吞饮小泡内;使用转染技术的铁摄取高于未使用组;T_2WI 和 T_2~*WI 扫描序列均见标记细胞呈信号下降,程度随标记浓度的增加而增强;T_2~*WI 图像信号强度变化更大。标记心肌细胞在T_2~*WI 序列也呈显著的低信号改变。结论 SPIO 可有效标记 ESC 及其分化的心肌细胞,对细胞活性和分化能力无明显影响。常规1.5TMR 仪可进行标记细胞成像。

关键词：干细胞磁共振成像超顺磁氧化铁

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Alfapump®implantable device in management of refractory ascites:An update

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World Journal of Hepatology 2022年第7期14卷 1344-1356页

作者： Delphine Weil-Verhoeven Vincent Di Martino Guido Stirnimann jean paul Cervoni Eric Nguyen-Khac Thierry Thévenot Service d’Hépatologie Et Soins Intensifs Digestifs CHRU Jean MinjozBesançon 25030France EA 4266 EPILAB Universitéde Bourgogne Franche-ComtéBesançon 25030France Department of Visceral Surgery and Medicine Inselspital University Hospital and University of BernBern 3010Switzerland Service d’Hépato-Gastroentérologie CHU Amiens-PicardieAmiens 80080France

Refractory ascites(RA)is a frequent and life-threatening complication of *** selected patients with RA,transjugular intrahepatic portosystemic shunt(TIPS)placement and liver transplantation(LT)are currently considered the best therapeutic alternatives to repeated large volume *** patients with a contraindication to TIPS or LT,the alfapump®system(Sequana Medical,Ghent,Belgium)has been developed to reduce the need for iterative paracentesis,and consequently to improve the quality of life and nutritional *** report here recent data on technical progress made since the first implantation,the efficacy and tolerance of the device,the position of the pump in the therapeutic arsenal for refractory ascites,and the grey areas that remain to be clarified regarding the optimal selection of patients who are potential candidates for this treatment.

关键词： Alfapump Refractory ascites Automated low flow ascites pump Cirrhosis Liver

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A High Dynamic Range GMI Current Sensor

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Journal of Sensor Technology 2012年第4期2卷 165-171页

作者： Aktham Asfour jean-paul Yonnet Manel Zidi Laboratoire de Génie Electrique de Grenoble (G2E-Lab) Institut Polytechnique de Grenoble ENSE3 Saint Martin d’Hères France

The design and performances of a high dynamic range DC-AC current sensor utilizing Giant Magneto-Impedance (GMI) are presented. The sensor is based on a GMI element with negative feedback. The sensing element is a 30 μm diameter GMI Co-based amorphous wire. It is curled to a toroidal core of 2 cm diameter. A bias magnetic field of about 650 A/m is applied to the GMI element to obtain an asymmetric GMI effect. A strong negative feedback is introduced to ensure linearity in a wide dynamic range. Analog conditioning electronics was fully developed. This includes a square wave oscillator based on an inverter trigger;a peak detector and a high gain amplifier with zero adjust. The GMI element is driven at a 3 MHz frequency and 5 mA peak-to-peak current. The closed-loop operations are investigated and the performances of the sensor are presented. DC current measurements are performed. The sensor exhibits good sensitivity and very good linearity, free from hysteresis, in a wide dynamic range of ±40 A. The sensitivity is about 0.24 V/A and the linearity error is about 0.02% of the full scale (FS). The hysteresis error is smaller than the measurement accuracy. AC current measurements using the developed sensor have also been successfully achieved. The sensor bandwidth in closed-loop was about 1.7 kHz.

关键词： GMI Current Sensor Negative Feedback DC-AC Current Measurements

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Altered Lignin Biosynthesis Improves Cellulosic Bioethanol Production in Transgenic Maize Plants Down-Regulated for Cinnamyl Alcohol Dehydrogenase

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Molecular Plant 2012年第4期5卷 817-830页

作者： Silvia Fornale Montserrat Capellades Antonio Encina Kan Wang Sami Irara Catherine Lapierre Katia Ruel jean-paul Joseleaue Jordi Berenguer Pere Puigdomenech Joan Rigau David Caparros-Ruiz Laboratori de Genetica Molecular Vegetal Centre de Recerca en AgriGenomica (CRAG) Consorci CSIC-IRTA-UAB-UB Edifici CRAG Campus UAB Bellaterra (Cerdanyola del Valles) 08193 Barcelona Spain Area de Fisiologia Vegetal Universidad de Lean 24071 Spain Center for Plant Transformation Iowa State University G405 Agronomy Hall Ames IA 50011-1010 USA Institut jean-Pierre Bourgin INRA-AgroParisTech UMR 1318 78026 Versailles cedex France Centre de Recherches sur les Macromolecules Vegetales-UPR-CNRS-5301 38041 Grenoble Cedex 09 France

Cinnamyl alcohol dehydrogenase （CAD） is a key enzyme involved in the last step of monolignol biosynthesis. The effect of CAD down-regulation on lignin production was investigated through a transgenic approach in maize. Trans- genic CAD-RNAi plants show a different degree of enzymatic reduction depending on the analyzed tissue and show alter- ations in cell wall composition. Cell walls of CAD-RNAi stems contain a lignin polymer with a slight reduction in the S-to-G ratio without affecting the total lignin content. In addition, these cell walls accumulate higher levels of cellulose and ara- binoxylans. In contrast, cell walls of CAD-RNAi midribs present a reduction in the total lignin content and of cell wall polysaccharides. In vitro degradability assays showed that, although to a different extent, the changes induced by the repression of CAD activity produced midribs and stems more degradable than wild-type plants. CAD-RNAi plants grown in the field presented a wild-type phenotype and produced higher amounts of dry biomass. Cellulosic bioethanol assays revealed that CAD-RNAi biomass produced higher levels of ethanol compared to wild-type, making CAD a good target to improve both the nutritional and energetic values of maize lignocellulosic biomass.

关键词： Maize lignification lignocellulosic biomass secondary cell wall.

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An electro-hydrostatic actuator for hybrid active-passive vibration isolation

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International Journal of Hydromechatronics 2018年第1期1卷 47-71页

作者： jean-paul Henderson Andrew Plummer Nigel Johnston Centre for Power Transmission and Motion Control Department of Mechanical Engineering University of Bath UK

A novel electro-hydrostatic actuator （EHA） for active vibration isolation has been designed, modelled and tested. The EHA consists of a brushless DC motor running in oil and integrated with a bidirectional gear pump, driving a hydraulic cylinder. The actuator is designed to be integrated into a flexible strut connecting a helicopter rotor hub and fuselage, to provide isolation at the dominant rotor vibration frequency of around 20 Hz. The resonant frequency of the EHA is tuned to provide some passive vibration isolation. Active control increases the isolation performance by compensating for damping losses, and provides isolation over a broader range of frequencies. Tests on a prototype demonstrated a four-fold reduction of the root-mean-square transmitted force and a near elimination at the fundamental frequency. The advantages of the resonant EHA are a wider range of operating frequencies than a purely passive system, and lower power consumption than a purely active system.

关键词： electro-hydrostatic actuator EHA tuned mass damper rotorcraft vibration isolation inerter hydromechatronics servohydraulics servopump vibration control.

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Effect of Nozzle Orientation on Droplet Size and Droplet Velocity from Vineyard Sprays

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Journal of Agricultural Science and Technology(B) 2015年第10期5卷 672-678页

作者： Ariane Vallet Cyril Tinet jean-paul Douzals Research Institute in Science and Technology for Environment and Agriculture (IRSTEA) Unite Mixte de Recherche lnJbrmation andTechnologies for Agro-Processes BP 5095 F-34196 Montpellier Cedex 5 France

Spray drift has become an important issue in pesticide application. Vineyard spraying is particularly interesting to consider, as pesticide droplets are not directed towards the ground but rather towards the targeted crop. The aim of this study was to investigate the influence of nozzle orientation on droplet size and droplet velocity using three different nozzles （IDK, TVI and TXA） used in vineyards. Two series of measurement were performed in order to assess the effect of the gravity on sprays. Droplet size and one-dimensional droplet velocity characteristics were measured using a phase Doppler particle analyser （PDPA）. Two planes, i.e., one horizontal and one vertical, were considered. Results suggest that the nozzle orientation slightly affects the size distribution, which is shifted towards larger droplets when nozzles spray horizontally compared to vertically spray, However, droplet axial velocity distribution is shifted towards lower values. Supposing that the only droplets which can reach the crop are those with an axial velocity greater than 1 m/s and a diameter larger than 100 lain, results showed significant differences according to the nozzle and orientation. More than 98.6% of the spray volume would reach the target whatever the orientation of the IDK nozzle, 78.8% of the spray volume would reach the crop when the TVI nozzle sprays horizontally, while only 16.0% of the spray volume would reach the crop when TXA nozzle sprays horizontally. This paper offers new perspectives in the comprehension and the optimization of the deposition process into the vegetation based from droplet size and velocity profiles from horizontally oriented sprays from flat fan or hollow cone nozzles.

关键词： Droplet size droplet velocity nozzle orientation vineyard sprays.

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Honeydew volatile emission acts as a kairomonal message for the Asian lady beetle Harmonia axyridis （Coleoptera： Coccinellidae）

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Insect Science 2012年第4期19卷 498-506页

作者： Pascal D. Leroy Stephanie Heuskin Ahmed Sabri Fran( ois J. Verheggen Julien Farmakidis Georges Lognay Philippe Thonart jean-paul Wathelet Yves Brostaux Eric Haubruge Departments of Functional and Evolutionary Entomology Departments of Analytical Chemistry University of Liege Gembloux Agro-BioTech Walloon Center of Industrial Biology University of Liege B40 4000 Sart-Tilman Departments of General and Organic Chemistry Departments of Appfied Statistics Computer Science and Mathematics University of Liege Gembloux Agro-Bio Tech Gembloux Belgium

The Asian lady beetle Harmonia axyridis Pallas is considered as an invasive species in most territories where it has been introduced. Because aphid honeydew acts as an attraetant for many aphid predators and parasitoids, the objectives of this work were to collect and identify the volatile compounds released from the aphid excretory product to evaluate how these semiochemicals could affect the H. axyridis foraging behavior. Twelve volatile chemicals were identified from the Megoura viciae Buckton honeydew including four alcohols, three ketones, three aldehydes, a pyrazine and a monoterpene. The volatiles 3-methyl-l-butanol and 3-methyl-butanal were highlighted as the two most abundant semiochemicals released from the M. viciae honeydew. Vieia faba L. plants treated with crude honeydew attracted more than 80% of the tested individuals with 40% of attracted beetles located on the plant. Four volatile compounds （3-hydroxy-2-butanone, 3-methyl-butanal, 3-methyl-1-butanol and limonene） were also highlighted to attract more than 75% of the coccinellids toward the odor source and to locate about 35% of them on the plants. Limonene was the most efficient attractant since 89% of the H. axyridis responded to this odor. The use of the identified semiochemicals as well as the composition of an artificial honeydew could certainly be helpful to control the dispersal of the Asian lady beetle H. axyridis.

关键词： aphid honeydew attractant Harmonia axyridis kairomone semiochemicals

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