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Science China Mathematics 2012年第2期55卷 277-283页

作者： FERNANdEZ-NIETO Enrique d. NOBLE Pascal VILA jean-Paul departamento de Matemdtica Aplicada I Universidad de Sevilla 41012 Sevilla Spain Universite de Lyon Universitd Lyon1 Institut Camille Jordan UMR CNRS 520843 blvd du 11 novembre 1918 F-69622 ViUeurbanne Cedex France Institut de Mathdmatiques de Toulouse UMR CNRS 5219 INSA de Toulouse 135 avenue de Rangueil 31077 Toulouse Cedex 4 France

In this note, we provide a consistant thin layer theory for power law and Bingham incompressible fluids flowing down an inclined plane under the effect of gravity. The derivation of such equations is based on formal asymptotic expansions of solutions of Cauchy momentum equations in the shallow water scaling and in the neighbourhood of steady solutions so that we can close the average equations on the fluid height h and the total discharge rate q.

关键词： shallow water equations asymptotic analysis non-Newtonian fluids

Petrographic, Geochemical and Metallogenical Context of the Geological Formations of the Goumere Region (North-East of Cote d’Ivoire): Implication to the Knowledge of Gold Mineralization

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International Journal of Geosciences 2024年第2期15卷 180-203页

作者： Fossou jean-Luc Hervé Kouadio Alain Nicaise Kouamelan Topka Kakeu Lionel Boya Roger Nicaise Kanga Laboratory of Geology Mineral and Energy Resources (LGRME) Faculty of Earth Science and Mineral Resources Félix Houphou&#235t Boigny University Abidjan C&#244te d’Ivoire

The Gouméré region is located in the North-East of Côte d’Ivoire and is located in the South-West of the Bui furrow. In order to highlight the geology of the area studied, 14 samples were taken for studies using petrographic, geochemical and metallogenic methods. The study of macroscopic and microscopic petrography made it possible to highlight two major lithological units: 1) a volcano-plutonic unit, formed of gabbros, basalt, volcaniclastics and rhyodacite;2) a sedimentary unit (microconglomerate). From a geochemical point of view, the results obtained indicate that the plutonites are gabbro and gabbro diorite while the volcanics have compositions of basaltic andesites, rhyolite and dacites. The sediments have a litharenitic to sublitharenitic character. The metallogenic study made it possible to highlight hydrothermal alterations and metalliferous paragenesis on the formations studied. Hydrothermal alteration is characterized by the presence of carbonation, silicification, sericitization, sulfidation and to a lesser degree chloritization. Metalliferous paragenesis consists of pyrite, chalcopyrite, hematite and magnetite.

关键词： Petrography Geochemistry Metallogeny Gouméré Côte d’Ivoire

Vitamin d, Parathyroid Hormone, Insulin Sensitivity and Islet β-Cell Secretory Function in diabetic Patients from South Kivu in the democratic Republic of Congo: Cross-Sectional Study

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Journal of diabetes Mellitus 2024年第2期14卷 81-94页

作者： dieudonne Masemo Bihehe Ahadi Birindwa Bwihangane jean-Paulin Mukonkole Mbo Michel Hermans Philippe Bianga Katchunga Faculté de Médecine H&#244pital Général de Référence de Panzi Université Evangélique en Afrique Bukavu DR Congo département de Biologie Faculté des Sciences Université Officielle de Bukavu Bukavu DR Congo département de Médecine Interne Université de Kisangani Kisangani DR Congo Service d’endocrinologie et de diabétologie Cliniques Universitaires Saint-Luc Université Catholique de Louvain Bruxelles Belgique département de Médecine Interne Cliniques Universitaires de Bukavu Université Officielle de Bukavu Bukavu DR Congo

Background: The role of vitamin d and parathyroid hormone in the metabolic profile of type 2 diabetes mellitus in sub-Saharan Africa has not been adequately assessed. The aim of this study was to determine the prevalence of low vitamin d level and secondary hyperparathyroidism and their association with insulin sensitivity and β-cell secretory function among Congolese type 2 diabetics. Methodology: Fasting glycaemia, fasting insulin, 25OH d3 and human parathyroid hormone (hPTH) were measured in one hundred and eighty-four type 2 diabetic patients followed as outpatients in South Kivu. Levels of 25OH d3 65 pg/ml defined low vitamin d and elevated parathyroid hormone levels, respectively. The HOMA model was used to measure insulin sensitivity and β-cell secretory function. Results: Medians (IQR) were 25.3 (20.4 - 32.4) ng/ml for 25OH d3 and 53.7 (38.4 - 115.7) pg/ml for hPTH. 58.7% of diabetics had insulin resistance, 126 (68.5%) had low vitamin d and 80 (43.5%) had hyperparathyroidism. In multivariate analysis, hPTH (partial r = −0.28;p = 0.0002) and 25OH d3 (partial r = 0.16;p = 0.03) showed an independent association with insulin sensitivity after adjustment for body mass index and waist circumference. Finally, hPTH (partial r = 0.27;p = 0.0002) was the sole determinant of β-cell secretory function. Conclusions: This study confirms the high prevalence of low vitamin d level and secondary hyperparathyroidism and their association with insulin resistance and impaired islet β-cell secretory function among Congolese with type 2 diabetes mellitus. Vitamin d and calcium supplementation should be envisaged for cases of deficiency in this region.

关键词： Vitamin d Parathyroid Hormone diabetes Mellitus Insulin Resistance South Kivu

Application of near-infrared spectroscopy for fast germplasm analysis and classification in multi-environment using intact-seed peanut(Arachis hypogaea L.)

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Oil Crop Science 2024年第2期9卷 132-141页

作者： Fentanesh Chekole Kassie Gilles Chaix Hermine Bille Ngalle Maguette Seye Coura Fall Hodo-Abalo Tossim Aissatou Sambou Olivier Gibert Fabrice davrieux Joseph Martin Bell jean-Francois Rami daniel Fonceka Joel Romaric Nguepjop department of Plant Biology and Physiology Faculty of SciencesUniversity of Yaounde IYaoundeP.O.Box 337Cameroon department of Plant Science College of AgricultureWolaita Sodo UniversitySodoP.O.Box 138Ethiopia CIRAd UMR AGAP InstitutMontpellierFrance AGAP Institut Univ MontpellierCIRADINRAEInstitut AgroMontpellierFrance ChemHouse Research Group MontpellierFrance Centre d’Etudes Regional Pour L’Amelioration de L’Adaptation a La Secheresse(CERAAS/ISRA) Route de KhomboleThiesBP 3320Senegal dispositif de Recherche et de Formation en Partenariat Innovation et Amelioration Varietale en Afrique de L’Ouest(IAVAO)CERAASRoute de KhomboleThiesBP 3320Senegal CIRAd UMR QUALISUDSaint PierreFrance

Peanut is a worldwide oilseed crop and the need to assess germplasm in a non-destructive manner is important for seed nutritional *** this study,Near Infrared Spectroscopy(NIRS)was applied to rapidly assess germplasm variability from whole seed of 699 samples,field-collected and assembled in four genetic and environmentbased sets:one set of 300 varieties of a core-collection and three sets of 133 genotypes of an interspecific population,evaluated in three environments in a large spatial scale of two countries,Mbalmayo and Bafia in Cameroon and Nioro in Senegal,under rainfed *** elemental spectra were gathered on six subsets of seeds of each sample,after three rotation scans,with a spectral resolution of 16 cm-1over the spectral range of867 nm to 2530 *** were then processed by principal component analysis(PCA)coupled with Partial least squares-discriminant analysis(PLS-dA).As results,a huge variability was found between varieties and genotypes for all NIR wavelength within and between *** magnitude of genetic variation was particularly observed at 11 relevant wavelengths such as 1723 nm,usually related to oil content and fatty acid *** yielded the most chemical attributes in three significant PCs(i.e.,eigenvalues>10),which together captured 93%of the total variation,revealing genetic and environment structure of varieties and genotypes into four clusters,corresponding to the four samples *** pattern of genetic variability of the interspecific population covers,remarkably half of spectrum of the core-collection,turning out to be the ***,a PLS-dA model was developed and a strong accuracy of 99.6%was achieved for the four sets,aiming to classify each seed sample according to environment *** confusion matrix achieved for the two sets of Bafia and Nioro showed 100%of instances classified correctly with 100%at both sensitivity and specificity,confirming that their seed quality was different f

关键词： Groundnut Oilseed Near infrared spectroscopy Germplasm analysis Environment Nutritional Breeding

Infrared spectroscopy analyses of air-CH_4 or air-CO gas flows interacting with polycrystalline CeO_2, La_2O_3 and Lu_2O_3 oxides

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Journal of Rare Earths 2012年第8期30卷 835-841页

作者： Bahcine BAKIZ Lamia BOURJA Abdeljalil BENLHACHEMI Frédéric GUINNETON Madjid ARAB jean-Raymond GAVARRI Institute Materials Microelectronics & Nanosciences of Provence UMR CNRS 6242 University SOUTH Toulon-Var Laboratory Materials & Environment Faculty of Sciences University Ibn Zohr

A comparative study of reactivity between air-CH4 or air-CO gas flows and CeO2, La2O3 and Lu2O3 rare earth oxides was per- formed using Fourier transform infrared spectroscopy analyses of CO2 gas resulted from the conversion of CH4 or CO gases. Polyerystalline samples of CeO2, La2O3 and Lu2O3 were first prepared by specific precipitation methods followed by low temperature calcination process. In the case of Lu2O3 oxide, a new specific route was proposed. Crystallite dimensions were determined by X-ray diffraction and transmission electron microscopy analyses. Morphologies were characterized using scanning electron microscopy. Specific surface areas were determined from Bnmauer-Emmett-Teller （BET） technique. Using infrared spectroscopy analyses, the conversion rates of CH4 or CO into CO2 were de- termined from the evolutions of CO2 vibrational band intensities, as a function of time and temperature. It was dearly established that, despite its low specific surface, the Lu2O3 oxide presented the highest capacity of conversion of CH4 or CO into CO2.

关键词： lutetium oxide rare earth oxides elaboration gas solid interactions infrared spectroscopy

Iron- and Ferritin-dependent Reactive Oxygen Species distribution： Impact on Arabidopsis Root System Architecture

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Molecular Plant 2015年第3期8卷 439-453页

作者： Guilhem Reyt Soukaina Boudouf Jossia Boucherez Frédéric Gaymard jean-Francois Briat Biochimie et Physiologie Moléculaire des Plantes Centre National de la Recherche Scientifique Institut National de la Recherche Agronomique Université Montpellier 2 SupAgro. Bat 7 2 place Viala 34060 Montpellier Cedex 1 France present address: Institute of Biological and Environmental Sciences University of Aberdeen Cruickshank Building St Machar Drive Aberdeen Scotland AB243UU UK

Iron （Fe） homeostasis is integrated with the production of reactive oxygen species （ROS）, and distribution at the root tip participates in the control of root growth. Excess Fe increases ferritin abundance, enabling the storage of Fe, which contributes to protection of plants against Fe-induced oxidative stress. AtFerl and AtFer3 are the two ferritin genes expressed in the meristematic zone, pericycle and endodermis of theAra- bidopsis thaliana root, and it is in these regions that we observe Fe stained dots. This staining disappears in the triple ferl-3-4 ferritin mutant. Fe excess decreases primary root length in the same way in wild-type and in ferl-3-4 mutant. In contrast, the Fe-mediated decrease of lateral root （LR） length and density is enhanced in ferl-3-4 plants due to a defect in LR emergence. We observe that this interaction between excess Fe, ferritin, and root system architecture （RSA） is in part mediated by the H_2O_2/O2·^- balance between the root cell proliferation and differentiation zones regulated by the UPB1 transcription factor. Meristem size is also decreased in response to Fe excess in ferritin mutant plants, implicating cell cycle arrest mediated by the ROS-activated SMR5/SMR7 cyclin-dependent kinase inhibitors pathway in the interaction between Fe and RSA.

关键词： roots development oxidative stress reactive oxygen species balance iron ferritins

Inheritance patterns of secondary symbionts during sexual reproduction of pea aphid biotypes

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Insect Science 2014年第3期21卷 291-300页

作者： jean Peccoud Joêl Bonhomme Frédérique Mahéo Manon de la Huerta Olivier Cosson jean-Christophe Simon INRA Institut de Génétique Environnement et Protection des Plantes (UMR IGEPP) Domaine de La Motte 35653 le Rheu cedex France

Herbivorous insects frequently harbor bacterial symbionts that affect their ecol- ogy and evolution. Aphids host the obligatory endosymbiont Buchnera, which is requiredfor reproduction, together with facultative symbionts whose frequencies vary across aphid populations. These maternally transmitted secondary symbionts have been particularlystudied in the pea aphid, Acyrthosiphon pisum, which harbors at least 8 distinct bacterial species （not counting Buchnera） having environmentally dependent effects on host *** particular, these symbiont species are associated with pea aphid populations feeding on specific plants. Although they are maternally inherited, these bacteria are occasionallytransferred across insect lineages. One mechanism of such nonmaternal transfer is paternal transmission to the progeny during sexual reproduction. To date, transmission of secondarysymbionts during sexual reproduction of aphids has been investigated in only a handful of aphid lineages and 3 symbiont species. To better characterize this process, we investigatedinheritance patterns of 7 symbiont species during sexual reproduction of pea aphids through a crossing experiment involving 49 clones belonging to 9 host-specialized biotypes, and117 crosses. Symbiont species in the progeny were detected with diagnostic qualitative PCR at the fundatrix stage hatching from eggs and in later parthenogenetic *** found no confirmed case of paternal transmission of symbionts to the progeny, and we observed that maternal transmission of a particular symbiont species （Serratia symbiotica）was quite inefficient. We discuss these observations in respect to the ecology of the pea aphid.

关键词： bacteria Homoptera paternal inheritance phytophagous insects symbiosis transmission failure

design methodology of permanent magnet generators for fixed-pitch tidal turbines with overspeed power limitation strategy

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Journal of Ocean Engineering and Science 2020年第1期5卷 73-83页

作者： Sofiane djebarri jean Frédéric Charpentier Frank Scuiller Mohamed Benbouzid ECAM Lyon LabECAMF69005 LyonFrance French Naval Academy IRENav EA 363429240 BrestFrance University of Brest UMR CNRS 6027 IRDL29238 BrestFrance Shanghai Maritime University 201306 ShanghaiChina

This paper deals with a design methodology of permanent magnets(PM)generators used for fixed-pitch tidal turbines in a marine renewable energy *** the case of underwater turbines,fixed-pitch tidal turbines could be very attractive and interesting to reduce maintenance operation by avoiding using such a complex electromechanical system for *** this technological case,one of the main control challenges is to ensure power limitation at high tidal current *** control mode can be achieved using the generator *** this context,this paper proposes an original and systemic design methodology to optimize the generator design taking into account the tidal turbine power limitation for high tidal currents velocities.

关键词： Tidal turbine Fixed-pitch turbine direct-drive PM generator design methodology Flux-weakening power limitation.

Twinning-induced plasticity(TWIP)effect in multi-phase metastable beta Zr-Nb alloys

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Journal of Materials Science & Technology 2023年第8期139卷 120-125页

作者： Junhui Tang Ahmed Zorgati jean-Baptiste Philippe Vermaut Frédéric Prim Fan Sun PSL Research University Chimie ParisTechCNRS-UMR8247Institut de Recherche de Chimie ParisParis 75005France Sorbonne University Ecole PolytechniquePalaiseau 91128France Gaillard Paris-Saclay University Commissariatàl’Energie AtomiqueService d’Etude des Matériaux IrradiésGif-Sur-Yvette 911191France PSL Research University Chimie ParisTechCNRS-UMR8247Institut de Recherche de Chimie ParisParis 75005France Sorbonne UniversityUPMC University ParisUFR926Paris 75005France

during the last decades,a large amount of scientific works had been devoted toβ-type Zr and Ti alloys for biomedical applica-tions due to their high strength,good corrosion resistance,low magnetic susceptibility and ... 详细信息

关键词： alloys corrosion resistance

Modification of the adsorption and catalytic properties of micro-and mesoporous materials by reactions with organometallic complexes

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Science China Chemistry 2010年第9期53卷 1862-1869页

作者： LEFEBVRE Frédéric PUTAJ Piotr BASSET jean-Marie Université de Lyon ICL C2P2 UMR 5265(CNRS-CPE-Université Lyon 1) LCOMS-CPE Lyon

This review describes the work of two laboratories in the field of the modification of micro-and mesoporous molecular sieves through reactions with organometallic *** modification of zeolites can occur inside the pore channels or on the external surface,depending on the size of the organometallic *** the modification occurs on the external surface,it results in a decrease of the pore entrance,which will lead in turn to a modification of the sorption properties of the zeolite,by decreasing the rate of the adsorption(mainly by a kinetic control).Such a material can be also used in catalysis,because the external acid sites,which are responsible for side-reactions,have been removed upon *** small organometallic complexes are used,they can fill the channels and cages of the zeolite and react with internal hydroxyl *** to the high acidity of zeolites,the reaction occurs very easily(for example at-100℃ on faujasite),in contrast to what is observed on the external surface,therefore leading to high metal *** that case,the modification of the sorption properties will be mainly related to a thermodynamic *** resulting materials can be useful in catalysis,by combining the activity of the organometallic complex and properties(for example shape-selectivity) of the *** of mesoporous molecular sieves occurs always in the pores and results in altering of the sorption properties of the solid,by changing the interaction type between the sorbent and the *** example the sorption isotherm of alkanes is changed from type II to type III according to the IUPAC nomenclature.

关键词： zeolites transition metals organometallic compounds adsorption properties