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Journal of Thermal Science 2004年第3期13卷 213-219页

作者： gérard J. POITRAS laurent-Emmanuel BRIZZI Yves gAgNON Université de Moncton Moncton (NB) CanadaLaboratoire d'études aérodynamiques Université de Poitiers 86960 Futuroscope FranceUniversité de Moncton Edmundston (NB) Canada

The flow inside a channel with surface mounted ribs is studied by numerical simulation and experimental flow visualization. Both the geometry with one rib and the geometry with two ribs, placed perpendicular to the flow, are studied, with particular emphasis on the effect of the variation of the distance between the ribs on the structure of the flow. Results show that, for Reynolds number flows of 400 and 1000 (based on the uniform incoming velocity and the height of the ribs), the flow reattaches between the ribs when they are separated by distances of 12h (h being the height of the ribs) and 6h, respectively. In this respect, however, the numerical results for the Reynolds number flow of 1000 are in contradiction with published results.

关键词： vortex methods flow visualization channel flows ribs.

BESTP——An automated Bayesian modeling tool for asteroseismology

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Research in Astronomy and Astrophysics 2021年第9期21卷 135-145页

作者： Chen Jiang laurent gizon Max-Planck-Institut für Sonnensystemforschung Justus-von-Liebig-Weg 337077 GöttingenGermany Institut für Astrophysik Georg-August-Universität GöttingenFriedrich-Hund-Platz 137077 GöttingenGermany School of Physics and Astronomy Sun Yat-Sen UniversityNo.135Xingang Xi RoadGuangzhou 510275China Center for Space Science NYUAD InstituteNew York University Abu DhabiAbu DhabiUAE

Asteroseismic observations are crucial to constrain stellar models with *** Estimation of STellar Parameters(BESTP)is a tool that utilizes Bayesian statistics and nested sampling Monte Carlo algorithm to search for the stellar models that best match a given set of classical and asteroseismic constraints from *** computation and evaluation of models are efficiently performed in an automated and multi-threaded *** illustrate the capabilities of BESTP,we estimate fundamental stellar properties for the Sun and the red-giant star HD *** both cases,we find models that are consistent with *** also evaluate the improvement in the precision of stellar parameters when the oscillation frequencies of individual modes are included as constraints,compared to the case when only the large frequency separation is *** the solar case,the uncertainties of estimated masses,radii and ages are reduced by 0.7%,0.3%and 8%*** HD 222076,they are reduced even more noticeably by 2%,0.5%and 4.7%*** also note an improvement of 10%for the age of HD 222076 when the gaia parallax is included as a constraint compared to the case when only the large separation is included as a constraint.

关键词： stars:interiors stars:oscillations methods:numerical asteroseismology

"Je t'aime moi non plus":A love-hate relationship between iron and phosphate

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Molecular Plant 2022年第1期15卷 1-2页

作者： laurent Nussaume Thierry Desnos Aix Marseille Univ CEACNRSBIAM.UMR7265SAVE(Signalisation pour I'Adaptation des Végétauxàleur Environnement)Saint-Paul lez DuranceFrance

Iron(Fe)and phosphate(Pi)are two essential nutrients for plant *** impact plant development differently and their respective deficiency leads to multiple physiological disorders,resulting in severe reduction of crop *** chemistry of these two elements is deeply inter-connected,as in the soil phosphate naturally associates to ferric oxides(resulting from aerobic conditions observed in most cultivated soils)to create insoluble complexes that can no longer be taken up by the plants'import systems.

关键词： soil oxides naturally

Endoscopic treatment of biliopancreatic pathology in patients with Whipple's pancreaticoduodenectomy surgical variants: Lessons learned from single-balloon enteroscopy-assisted ERCP

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Hepatobiliary & Pancreatic Diseases International 2024年第5期23卷 509-514页

作者： Rodrigo garcés-Durán laurent Monino Pierre H Deprez Hubert Piessevaux Tom g Moreels Department of gastroenterology and Hepatology Universitécatholique de LouvainCliniques Universitaires Saint-LucAvenue Hippocrates 101200 BrusselsBelgium

Background: Endoscopic treatment of biliopancreatic pathology is challenging due to surgically altered anatomy after Whipple's pancreaticoduodenectomy. This study aimed to evaluate the feasibility and safety of single-balloon enteroscopy-assisted endoscopic retrograde cholangiopancreatography(SBE-ERCP) to treat biliopancreatic pathology in patients with Whipple's pancreaticoduodenectomy surgical variants. Methods: We retrospectively analyzed 106 SBE-ERCP procedures in 46 patients with Whipple's variants. Technical and clinical success rates and adverse events were evaluated. Results: Biliary SBE-ERCP was performed in 34 patients and pancreatic SBE-ERCP in 17, including 5 with both indications. From a total of 106 SBE-ERCP procedures, 76 were biliary indication with technical success rate of 68/76(90%) procedures and clinical success rate of 30/34(88%) patients. Mild adverse event rate was 8/76(11%), without serious adverse events. From a total of 106 SBE-ERCP procedures, 30 were pancreatic indication with technical success rate of 24/30(80%) procedures( P = 0.194 vs. biliary SBEERCP) and clinical success rate of 11/17(65%) patients( P = 0.016 vs. biliary SBE-ERCP). Mild adverse event rate was 6/30(20%)( P = 0.194 vs. biliary SBE-ERCP), without serious adverse events. After SBE-ERCP failure, endoscopic ultrasound-guided drainage, percutaneous drainage and redo surgery were alternative therapeutic options. Conclusions: Biliopancreatic pathology after Whipple's pancreaticoduodenectomy variants can be treated using SBE-ERCP without serious adverse events. Technical and clinical success rates are high for biliary indications, whereas clinical success rate of pancreatic indications is significantly lower. SBE-ERCP can be considered as first-line treatment option in this patient group with surgically altered anatomy.

关键词： Enteroscopy Endoscopic retrograde cholangiopancreatography Pancreaticoduodenectomy Surgically altered anatomy Whipple’s procedure

Dietary enrichment of edible insects with omega 3 fatty acids

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Insect Science 2020年第3期27卷 500-509页

作者： Dennis g.A.B.Oonincx Sophie laurent Margot E.Veenenbos Joop J.A.van Loon Department of Animal Sciences Animal Nutrition GroupWageningen UniversityWageningenthe Netherlands Laboratory of Entomology Department of Plant SciencesWageningen UniversityWageningenthe Netherlands Sophie laurent ON IRISFood Process EngineeringUMR CNRS 6144 GEPEANantes Cedex 3France

Edible insects are advocated as sustainable and healthy food and ***,commercially produced insects are often low in n‐3 fatty acids and have suboptimal n‐6/n‐3 ratios.A certain amount and proportion of these FAs is required to optimize human *** oil consists primarily(57%)out of alpha‐linolenic *** experiment was conducted to quantify the effect of flaxseed oil provision on fatty acid composition and to determine the quantity needed to attain a beneficial n‐6/n‐3 *** species were used in the experiment:house crickets(Acheta domesticus[L.]),lesser mealworms(Alphitobius diaperinus[Pfanzer])and black soldier flies(Hermetia illucens[L.]).These were provided with either a control diet or a diet enriched with 1%,2%,or 4%flaxseed oil during their larval/nymphal *** acid profiles of diets and insects were determined via gC‐*** three species had distinct fatty acid profiles on all four diets,but responded similarly to flaxseed oil *** each percent added to the diet,the alpha‐linolenic acid content of the insects increased by 2.3%–2.7%.Four percent addition increased the n‐3 fatty acid content 10–20 fold in the three species and thereby strongly decreased n‐6/n‐3 ratios from 18–36 to 0.8–2.4.A ratio below 5 is considered optimal for human health and was achieved by 2%flaxseed oil inclusion for house crickets and lesser mealworms,and at 1%inclusion for black soldier *** a source of n‐3 fatty acids to insect diets can thus improve the nutritional quality of insects.

关键词： Acheta domesticus Alphitobius diaperinus diet fatty acids Hermetia illucens

Woody plant assemblage and the structure of miombo woodland along a disturbance gradient in Hurungwe, Zambezi Valley, Zimbabwe

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Journal of Forestry Research 2021年第5期32卷 1867-1877页

作者： Tatenda gotore Hilton gTNdagurwa Shakkie Kativu Denis gautier laurent gazull Forest Research Centre P.O.Box HG595HighlandsHarareZimbabwe Department of Forest Resources and Wildlife Management Faculty of Applied ScienceNational University of Science and TechnologyP.O.Box AC 939 AscotBulawayoZimbabwe School of Animal Plant and Environmental SciencesUniversity of the WitwatersrandPrivate Bag 3Wits 2050South Africa Department of Biological Sciences Faculty of ScienceUniversity of ZimbabweP.O.Box MP167 Mount PleasantHarareZimbabwe Forêt et Sociétés Univ MontpellierCIRADTA C-105/DCampus international de Baillarguet34398 Montpellier Cedex 5France

Miombo woodlands near human settlements are under significant pressures from human activities,with negative consequences on their structure and *** studies are limited,we assessed the structure and species composition of a portion of miombo woodland along an increasing disturbance gradient from a national park,through a buffer zone to communal lands in northeast *** concentric plots of 2 and 11 m radii were established in each area to record woody species composition,diameter,height,basal area,density and volume as well as evidence of *** of site,growth stage and their interaction on vegetation diversity and structural parameters were tested using a general linear model(gLM).Principal component analysis(PCA) tested the association between species and site and ANOVA the differences in the level of disturbance across *** diversity did not differ between sites except for evenness,which increased with *** and richness were greater in seedlings and saplings than mature trees across sites,*** and mature tree diameters differed significantly between *** and density of mature trees declined with increasing disturbance while seedling densities peaked at intermediate disturbance levels(buffer zone).Tree harvesting,was more evident in the buffer zone and in the communal area relative to the national *** contrast,fire frequency was greater in the national park and in the buffer zone relative to the communal *** results of this study identify a true miombo woodland dominated by Brachystegia boehmii with a stable population,as illustrated by an inverse-J shape in diameter class distribution on all sites,and that these woodlands are generally resilient to disturbances,maintaining similar species composition and structure at various levels of ***,continued monitoring of disturbance levels and miombo woodland response is recommended to ensure sustainable utilisation of

关键词： Miombo woodlands cComposition Diversity Structure Anthropogenic disturbances

Sedimentary facies and paleoenvironmental interpretation of a Holocene marsh in the gironde Estuary in France

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Acta Oceanologica Sinica 2006年第6期25卷 52-62页

作者： WANg Jianhua MASSE laurent TASTET Jean -Pierre Department of Earth Sciences Sun Yat-sen （Zhongshan） University Guangzhou 510275 China Départment de géologie et Océanographie Université Bordeaux I 33405 Talence cédèx France

The Monards Marsh is located on the northeastern bank of the gironde Estuary in France. Lithological, sedimentolngical and mi- cropalacontological investigations were made on four cores to determine the evolution of Holocene sedimentary environments and processes in this area over the last 6 000 a. Three main lithological facies are distinguished from bottom to top：（ 1 ） grey laminated silty-sandy clay ; （2） homogeneous dark grey silty clay ; and （ 3 ） compact silty clay. About 26 benthic foraminifera species are identified and divided into six groups according to their ecological characteristics. In association with lithology, sedimentary structures and grainuiometry, the distribution of foraminifera group is used to define external slikke, internal slikke, external schorre, internal schorre, and continental marsh facies. Combined with 14C（AMS） dating, these data indicate four successive paleoenvironments in the Monards Marsh：（ 1 ） Holocene transgression resuited in the development of a basal schorre facies overlying fluvial deposits that transformed to slikke facies sedimentation; the transgression maximum occurred around 5 600 to 5 4430 a BP and was inferred to be associated with the last phase of the rapid Holocene sea-level rise; （2） post-trangressive maximum sedimentation resuited in a regressive sequence of deposits prograding towards the estuary, corresponding to the stahilisation of sea level after 5 4430 a BP; （3） a slight positive tendency in the sea level around 2 800 a BP recorded in the central part of the marsh; and （4） the wetland to a continental marsh environment. The sequential pattern for the evolution of wetlands in this estuarine area during the Holocene is fluvial facies - blackish schorre facies - slikke facies - blackish schorre facies - continental marsh facies. Characteristics of sedimentary facies distribution and evolution reveal that the development of Holocene salt marsh in this area was controlled by the sea-level change and tidal r

关键词： marsh sedimentation benthic foraminifera,^ 14C dating Holocene sea-level fluctuation paleoenvironment

AP2/ERF transcription factors orchestrate very long chain fatty acid biosynthesis during Arabidopsis lateral root development

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Molecular Plant 2021年第2期14卷 205-207页

作者： Soazig guyomarc'h Yohann Boutte laurent Laplaze UMR DIADE Universitéde MontpellierIRDMontpellierFrance LBM BordeauxFrance

One key factor defining root system architecture is root branching,i.e.,the process of the formation of new root axes,called lateral roots(LRs),from an existing *** the model plant Arabidopsis thaliana,LRs originate from preselected pericycle cells that divide to create an LR primordium(LRP)that grows and eventually forms a new root apical meristem(Banda et al.,2019).During this developmental process,cell-fate acquisition is very plastic and depends on positional information rather than on cell lineage(Banda et al.,2019).Importantly,LR formation occurs inside the parent root,and the LRP must grow through overlying tissues before emerging into the *** LR emergence process is controlled by dynamic intercellular signaling and involves a tight coordination of cellular responses in the LRP and surrounding tissues(Banda et al.,2019).In particular,the growing LRP rapidly pushes against the overlying endodermis,a layer of cells mechanically reinforced by the Casparian *** crossing of the endodermis by the LRP between stagesⅣand V has been proposed as an important developmental checkpoint during LR development(Banda et al.,2019).

关键词： eventually Arabidopsis branching

Transcripts switched off at the stop of phloem unloading highlight the energy efficiency of sugar import in the ripening V. vinifera fruit

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Horticulture Research 2021年第1期8卷 2770-2784页

作者： Stefania Savoi laurent Torregrosa Charles Romieu AgAP Montpellier UniversityCIRADINRAeInstitut Agro-MontpellierUMT genovigne340602 place VialaMontpellier CEDEXFrance

Transcriptomic changes at the cessation of sugar accumulation in the pericarp of Vitis vinifera were addressed on single berries re-synchronised according to their individual growth *** net rates of water,sugars and K+accumulation inferred from individual growth and solute concentration confirmed that these inflows stopped simultaneously in the ripe berry,while the small amount of malic acid remaining at this stage was still being oxidised at low ***-synchronised individual berries displayed negligible variations in gene expression among ***-seq studies revealed sharp reprogramming of cell-wall enzymes and structural proteins at the stop of phloem unloading,associated with an 80%repression of multiple sugar transporters and aquaporins on the plasma or tonoplast membranes,with the noticeable exception of H^(+)/sugar symporters,which were rather weakly and constitutively *** was verified in three genotypes placed in contrasted thermo-hydric *** prevalence of SWEET suggests that electrogenic transporters would play a minor role on the plasma membranes of SE/CC complex and the one of the flesh,while sucrose/H+exchangers dominate on its ***-regulatory elements present in their promoters allowed to sort these transporters in different groups,also including specific TIPs and PIPs paralogs,and cohorts of cell wall-related *** with simple thermodynamic considerations,these results lead to propose that H^(+)/sugar exchangers at the tonoplast,associated with a considerably acidic vacuolar pH,may exhaust cytosolic sugars in the flesh and alleviate the need for supplementary energisation of sugar transport at the plasma membrane.

关键词： sugar negligible allowed