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Caffeoyl Derivatives: Major Antioxidant Compounds of Some Wild Herbs of the AsteraceaeFamily

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Food and Nutrition Sciences 2011年第3期2卷 181-192页

作者： Didier Fraisse Catherine Felgines Odile Texier jean-louis Lamaison 不详

The polyphenolic composition and antioxidant activity of the aerial parts of 18 medicinal or food plants of the As- teraceae family were studied. Five main caffeoyl derivatives were determined individually by HPLC and compared with levels determined by colorimetry for total dihydroxycinnamic derivatives and total phenolics. The aim of this study was to assess the contribution of these constituents to the antioxidant activity of the herbs determined by DPPH radical scavenging tests. Significant correlations were found between total phenolic (R2 = 0.8904), total dihydroxycinnamic derivative (R2 = 0.8529) and total caffeoyl derivative (R2 = 0.7172) concentrations and the DPPH-scavenging ability of all herbs. The antioxidant activity of the main constituents, including chicoric acid (EC50 = 8.24 μmol/l) or 3,5- dicaffeoylquinic acid (EC50 = 7.62 μmol/l), was very high compared to vitamin C (EC50 = 15.66 μmol/l). Thus, for each species, antioxidant activity mainly involves the major caffeoyl derivatives. The contribution to antioxidant activity were assessed as 48.92% for 3,5-dicaffeoylquinic acid in Tanacetum parthenium (30.08 g/kg), and 68.96% for chicoric acid in Taraxacum officinale (34.08 g/kg). The main caffeoyl derivatives among polyphenols can be considered as the major antioxidant compounds of the studied Asteraceae herbs.

关键词： Plants Asteraceae Caffeoyl Derivatives Antioxidant

Biosensors for Pesticide Detection: New Trends

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American Journal of Analytical Chemistry 2012年第3期3卷 210-232页

作者： Audrey Sassolas Beatriz Prieto-Simón jean-louis Marty Laboratoire IMAGES EA 4218 Université de Perpignan via Domitia Perpignan France Nanobioengineering Group Institute for Bioengineering of Catalonia Barcelone Spain

Due to the large amounts of pesticides commonly used and their impact on health, prompt and accurate pesticide analysis is important. This review gives an overview of recent advances and new trends in biosensors for pesticide detection. Optical, electrochemical and piezoelectric biosensors have been reported based on the detection method. In this review biosensors have been classified according to the immobilized biorecognition element: enzymes, cells, antibodies and, more rarely, DNA. The use of tailor-designed biomolecules, such as aptamers and molecularly imprinted polymers, is reviewed. Artificial Neural Networks, that allow the analysis of pesticide mixtures are also presented. Recent advances in the field of nanomaterials merit special mention. The incorporation of nanomaterials provides highly sensitive sensing devices allowing the efficient detection of pesticides.

关键词： Biosensors Pesticides

Modelling of the Quantum Transport in Strained Si/SiGe/Si Superlattices Based P-i-n Infrared Photodetectors for 1.3 - 1.55 μm Optical Communication

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Modeling and Numerical Simulation of Material Science 2014年第1期4卷 37-52页

作者： Noureddine Sfina Naima Yahyaoui Moncef Said jean-louis Lazzari Department of Physics Faculty of Sciences of Monastir Laboratory of Condensed Matter and Nanosciences (LMCN) Monastir Tunisia Interdisciplinary Nanoscience Centre of Marseille (CINaM) Aix-Marseille University Marseille France

In this paper, a p-i-n heterojunction based on strain-compensated Si/Si1-xGex/Si multiple quantum wells on relaxed Si1-yGey is proposed for photodetection applications. The Si1-yGey/Si/Si1-xGex/Si/Si1-yGey stack consists in a W-like potential profile strain-compensated in the two low absorption windows of silica fibers infrared (IR) photodetectors. These computations have been used for the study of p-i-n infrared photodetectors operating at room temperature (RT) in the range 1.3 - 1.55 μm. The electron transport in the Si/Si1-xGex/Si multi-quantum wells-based p-i-n structure was analyzed and numerically simulated taking into account tunneling process and thermally activated transfer through the barriers mainly. These processes were modeled with a system of Schrodinger and kinetic equations self-consistently resolved with the Poisson equation. Temperature dependence of zero-bias resistance area product (RoA) and bias-dependent dynamic resistance of the diode have been analyzed in details to investigate the contribution of dark current mechanisms which reduce the electrical performances of the diode.

关键词： Strained SiGe/Si Quantum Wells Band Structure Device Engineering P-i-n Infrared Photodetectors

Annual and Diurnal Variabilities in the Critical Frequency (foF2) during Geomagnetic Fluctuating Activity over Solar Cycles 21 and 22 at Ouagadougou

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Atmospheric and Climate Sciences 2018年第4期8卷 435-445页

作者： Abidina Diabaté Frédéric Ouattara jean louis Zerbo Laboratoire de Recherche en Energétique et Météorologie de l’Espace (LAREME) Université Norbert Zongo Koudougou Burkina Faso Université Nazi Boni Bobo Dioulasso Burkina Faso Laboratoire d’Energies Thermiques Renouvelables (L.E.T.RE) Université Ouaga 1 Pr Joseph Ki-Zerbo Ouagadougou Burkina Faso

Geomagnetic activity is characterized by four solar wind conditions. Each condition has specific impact on ionosphere. This paper review on fluctuating activity effects on ionosphere F2 layer through its critical frequency foF2 variations. Under fluctuating wind conditions, we have investigated on annual, diurnal and seasonal variations of foF2 during solar cycles 21 and 22 phases covered by Ouagadougou ionosonde station data (Lat: 12.5°N;Long: 358.5°E;dip: 1.43°). Our investigations show that foF2 annual’ variability is in phase with solar cycle. The diurnal variation is “noon bite out” most of the time except for the solar maximum where we have a morning peak testifying to the fact that the vertical drift E × B is disturbed. The seasonal variations show that the fluctuating activity has no particular effect on certain characteristics of the equatorial ionosphere such as electrojet and vertical drift E × B. However, the increase of the electric field pre-reversal phenomenon in autumn is a characteristic effect observed during the fluctuating activity.

关键词： Critical Frequency Solar Cycle Seasonal Diurnal Fluctuating Activity

Direct Determination of Radionuclides in the Body Optimisation of Measurements Parameters and Results Analysis

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World Journal of Nuclear Science and Technology 2011年第3期1卷 87-110页

作者： jean louis Genicot Telma Fonseca Gary Kramer André Wambersie 不详

Whole body counting (WBC) benefits from new types of detectors and methodologies. It has found applications in areas such as in medicine, protection of workers and of population. The design of a WBC facility should be tailored to the type of application. Monte Carlo calculations help to improve the reliability of the calibration of a facility, particularly for non-standard measurements (child, etc.), help in optimizing shielding of counting rooms, preventing large systematic errors and lowering detection limits. In vivo counting may be used to evaluate the distribution of radionuclides in organs for metabolic studies with multiple detectors or with a scan of the body. Reduction of detection levels by background reduction is limited. Improved sensitivity can be obtained by adapting the detector type and size to the measured photon energy. The benefit of comparison exercises and training courses are demonstrated. Further improvements in accuracy can be expected from cooperative works with other techniques: indirect methods (urines and faeces) and passive detectors placed correctly on the body can in the case of high levels of contamination can be used to improve the burden assessment.

关键词： WBC in vivo Counting Internal Dosimetry Internal Contamination

The catalytic properties of DNA G‐quadruplexes rely on their structural integrity

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Chinese Journal of Catalysis 2021年第7期42卷 1102-1107页

作者： Jielin Chen Mingpan Cheng Jiawei Wang Dehui Qiu David Monchaud jean‐louis Mergny Huangxian Ju Jun Zhou State Key Laboratory of Analytical Chemistry for Life Science School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023JiangsuChina Institut de Chimie Moléculaire Universitéde Bourgogne(ICMUB)CNRS UMR6302UBFC Dijon 21000France Laboratoire d’Optique et Biosciences Ecole PolytechniqueCNRSINSERMInstitut Polytechnique de Paris91128 PalaiseauFrance

The influence of the G‐quartet structural integrity on the catalytic activity of the G‐quadruplex(G4)was investigated by comparing the G4‐DNAzyme performances of a series of G4s with a G‐vacancy site and a G‐triplex(G‐tri).The results presented herein not only confirm that the structural integrity of the 3'‐end G‐quartet is necessary for G4s to be catalytically competent but also show how to remediate G‐vacancy‐mediated catalytic activity losses via the addition of guanine surrogates in an approach referred to as G‐vacancy complementation strategy that is applicable to parallel G4s ***,this study demonstrates that the terminal G‐quartet could act as a proximal coordinating group and cooperate with the flanking nucleotide to activate the hemin cofactor.

关键词： G‐quadruplex G‐quadruplex DNAzyme G‐vacancy G‐quartet integrity Guanine surrogate

Role of endoscopic ultrasound in the screening and follow-up of high-risk individuals for familial pancreatic cancer

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World Journal of Gastroenterology 2019年第34期25卷 5082-5096页

作者： Diane Lorenzo Vinciane Rebours Frédérique Maire Maxime Palazzo jean-Michel Gonzalez Marie-Pierre Vullierme Alain Aubert Pascal Hammel Philippe Lévy louis de Mestier Pancreatology Department Beaujon HospitalAssistance Publique-Hopitaux de ParisClichyand Paris Diderot UniversityParis 75013France INSERM UMR1149Paris 92110France Departement of Gastroenterology Aix Marseille university-APHM-Hopital NordMarseille 13000France Radiology Department Beaujon HospitalAssistance Publique-Hopitaux de ParisClichyand Paris Diderot UniversityParis 92110France Oncology Department Beaujon HospitalAssistance Publique-Hopitaux de ParisClichyand Paris Diderot UniversityParis 92110France

Managing familial pancreatic cancer(FPC)is challenging for gastroenterologists,surgeons and ***-risk individuals(HRI)for pancreatic cancer(PC)(FPC or with germline mutations)are a heterogeneous group of subjects with a theoretical lifetime cumulative risk of PC over 5%.Screening is mainly based on annual magnetic resonance imaging(MRI)and endoscopic ultrasound(EUS).The goal of screening is to identify early-stage operable cancers or high-risk precancerous lesions(pancreatic intraepithelial neoplasia or intraductal papillary mucinous neoplasms with high-grade dysplasia).In the literature,target lesions are identified in 2%-5%of HRI who undergo *** appears to provide better identification of small solid lesions(0%-46%of HRI)and chronicpancreatitis-like parenchymal changes(14%-77%of HRI),while MRI is probably the best modality to identify small cystic lesions(13%-49%of HRI).There are no specific studies in HRI on the use of contrast-enhanced harmonic *** can also be used to obtain tissue ***,there is still limited evidence on the accuracy of imaging procedures used for screening or agreement on which patients to *** cost-effectiveness of screening is also *** new EUS-related techniques,such as searching for DNA abnormalities or protein markers in pancreatic fluid,appear to be promising.

关键词： Endoscopic ultrasound Familial pancreatic cancer Fine-needle aspiration Intraductal papillary mucinous neoplasm Pancreatic cancer Pancreatic intraepithelial neoplasia Pancreatic cancer screening guidelines

Glycemic Index of Sugars Extracted from Immature Coconut Water: Case of Coconut Palms (Cocos nuciferaL.) WAT, MYD and PB121+

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Journal of Biosciences and Medicines 2018年第8期6卷 99-110页

作者： Akpro Lathro Anselme Gbogouri Grodji Albarin Konan Konan jean-louis Gbakayoro jean Brice Nemlin Gnopo jean Laboratory of Nutrition and Food Safety UFR-STA University Nangui Abrogoua Abidjan C&ocirc te d’Ivoire Laboratory of Technology and Oil Analyse Research Station Marc Delorme CNRA Abidjan C&ocirc te d’Ivoire Technological Research Station of Bingerville CNRA Abidjan C&ocirc te d’Ivoire

In order to do a best stipulation on her consumption, it is necessary to know if a food provoke faintly, fairly or highly the glyceamia. The aim of this work was to evaluate the glycemic index of coconut water sugar from three coconuts varieties. So, with a cohort of 15 people, a capillary blood was collect after sugar ingestion and the glycaemia read directly on a glucometer. The result showed that the brown and white sugar from coconut sugar can be classified as low glycemic index food. Also, the glycemic indexes of white coconut water sugar are 2 to 3 more lower than that the brown sugar. The glycemic indexes of sugars vary according to the variety of coconut used. The sugars of the coconut palm (MYD) are more hyper-glycemic than those of the hybrid (PB121+) which is more hyperglycemic than the sugars of the coconut palm (WAT). Thus, with a controlled consumption, the coconut water sugars could be the sugars that are best for the health of the healthy and diabetic populations because it raises slightly the postprandial glucose.

关键词： Glycemic Index Brown Sugar White Sugar Coconut Water Sugar Glycemic Response

Transjugular intrahepatic portosystemic shunt for the management of acute variceal hemorrhage

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World Journal of Gastroenterology 2013年第37期19卷 6131-6143页

作者： Romaric Loffroy louis Estivalet Violaine Cherblanc Sylvain Favelier Pierre Pottecher Samia Hamza Anne Minello Patrick Hillon Pierre Thouant Pierre-Henri Lefevre Denis Krausé jean-Pierre Cercueil Department of Vascular Oncologic and Interventional RadiologyUniversity of Dijon School of MedicineBocage Teaching Hospital Department of Intensive Care Medicine Gastroenterology and HepatologyUniversity of Dijon School of MedicineBocage Teaching Hospital

Acute variceal hemorrhage,a life-threatening condition that requires a multidisciplinary approach for effective therapy,is defined as visible bleeding from an esophageal or gastric varix at the time of endoscopy,the presence of large esophageal varices with recent stigmata of bleeding,or fresh blood visible in the stomach with no other source of bleeding *** of blood products,pharmacological treatments and early endoscopic therapy are often effective;however,if primary hemostasis cannot be obtained or if uncontrollable early rebleeding occurs,transjugular intrahepatic portosystemic shunt(TIPS)is recommended as rescue *** TIPS represents a major advance in the treatment of complications of portal *** variceal hemorrhage that is poorly controlled with endoscopic therapy is generally well controlled with TIPS,which has a 90%to 100%success ***,TIPS is associated with a mortality of 30%to 50%in such a *** TIPS should be considered early in patients with refractory variceal bleeding once medical treatment and endoscopic sclerotherapy failure,before the clinical condition ***,admission to specialized centers is mandatory in such a setting and regional protocols are essential to be organized *** review article discusses initial management and then focuses on the specific role of TIPS as a primary therapy to control acute variceal hemorrhage,particularly as a rescue therapy following failure of endoscopic approaches.

关键词： Cirrhosis Portal hypertension Transjugular intrahepatic portosystemic shunt Variceal hemorrhage