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Multiscattering-enhanced absorbance to enable the sensitive analysis of extremely diluted biological samples: Determination of oxidative potential in exhaled air

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Medicine in Novel Technology and Devices 2022年第2期14卷 62-66页

作者： Sami Goekce Nicolas Concha-Lozano Jean-Jacques Sauvain Maud Hemmendinger Alejandro Portela Elise Sergent pascal Andujar Jean-Claude Pairon pascal Wild Guillaume Suarez Center for Primary Care and Public Health Lausanne UniversityLausanneSwitzerland Forensic Toxicology and Chemistry Unit CURMLLausanne University HospitalGeneva University HospitalsSwitzerland International University of Catalonia Bioengineering Institute of TechnologyBarcelonaSpain CHI Creteil Service Pathologies Professionnelles et de L’EnvironnementCreteilFrance Universite Paris-Est Creteil Faculte de SanteInstitut Sante Travail Paris-Est CreteilFrance Inserm U955 Team 4CreteilFrance INRS Scientific ManagementVandoeuvre Les NancyFrance

Direct determination of the oxidative potential in exhaled air(OPEA)as a biological indicator of the redox balance status in airways requires an extremely sensitive sensing approach to counterbalance the high dilution of the exhaled air *** opposite to standard colorimetric assays based on Beer-Lambert Law,the use of simple multiscattering-enhanced absorbance(MEA)strategy results in an improved photonic sensing *** on this strategy and using the ferrous-xylenol orange assay,analytical performances allowing the detection of 3 pmol of H_(2)O_(2) could be *** comparative analysis of photometric configurations–standard vs MEA–highlights the large absorbance gain obtained for tiny H_(2)O_(2) amounts–from 0 to 30 pmol–whereas similar sensing trends are observed at higher concentration *** automated introduction of exhaled air sample into the reaction compartment via needle-impinger coupled with the MEA-based photonic cell enables ultrasensitive determination of OPEA in short time(<5 min).A pilot study conducted on healthy subjects(n=22)and chronic obstructive pulmonary disease(COPD)patients(n=23)volunteers shows a significant increase of the OPEA for COPD versus controls and strong negative correlation between OPEA and spirometry parameters(Tiffeneau index:FEV1/FVC)for ex-/*** perspectives to assess inflammatory episodes in obstructive lung diseases are thus made possible using this sensing approach.

关键词： Absorbance enhancement Photonic device Oxidative potential Exhaled air COPD Pilot study

Positive effect of spring advance on the diet quality of an alpine herbivore

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Integrative Zoology 2022年第1期17卷 78-92页

作者： Johan ESPUNYES Emmanuel SERRANO Sara CHAVES Jordi BARTOLOMÉ Pierre MENAUT Elena ALBANELL pascal MARCHAND Kévin FOULCHÉ Mathieu GAREL Wildlife Ecology and Health group(WE&H)i Servei d’Ecopatologia de la Fauna Salvatge(SEFaS) Department of Animal Medicine and SurgeryFaculty of Veterinary MedicineUniversitat Autònoma de BarcelonaBellaterraSpain Wildlife Conservation Medicine Research Group(WildCoM) Department of Animal Medicine and SurgeryFaculty of Veterinary MedicineUniversitat Autònoma de BarcelonaBellaterraSpain Research and Conservation Department Zoo de BarcelonaBarcelonaSpain Group of Ruminant Research(G2R) Department of Animal and Food ScienceFaculty of Veterinary MedicineUniversitat Autònoma de BarcelonaBellaterraSpain French Agency for Biodiversity Direction Régionale OccitanieService d’Appui aux Acteurs et Mobilisation du TerritoireVilleneuve de RivièreFrance French Agency for Biodiversity Direction de la Recherche et Appui ScientifiqueUnitéOngulés SauvagesGièresFrance

Changes in vegetation phenology related to global warming are having alarming effects on the life history traits of many herbivore *** changes are particularly critical in alpine ecosystems,where strong climate limitations on plant growth make seasonal synchronization imperative for the growth,reproduction and survival of ***,despite the pivotal role of resource-use strategies on the performances of such species,few studies have explicitly assessed the mechanistic impact of climate change on their *** aimed to fill this gap by studying the effect of spring onset on the dietary composition and quality of a medium-size alpine herbivore while considering density-dependent processes and age-and sex-specific differences in foraging *** an exceptional,long-term(24 years)direct individual-based dietary monitoring of a Pyrenean chamois population(Rupicapra pyrenaica pyrenaica),we showed that ongoing earlier onsets of spring are leading to an earlier access to high-quality forage and therefore a higher diet quality at a fixed date,without apparent changes in diet *** also showed that at high densities,intraspecific competition reduced diet quality by driving animals to feed more on woody plants and less on nutritious forbs and *** assessing the mechanistic effects of global warming on the dietary patterns of species at the center of trophic networks,this study is an essential step for predictive models aiming at understanding the ongoing ecosystem consequences of the global climatic crisis.

关键词： cuticle microhistological analysis diet composition near-infrared spectroscopy Rupicapra pyrenaica

Why Is the Climate Forcing of Sulfate Aerosols So Uncertain?

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Advances in Atmospheric Sciences 2001年第6期18卷 1103-1120页

作者： Hu Rongming, Serge Planton, Michel Deque, pascal Marquet and Alain Braun Centre national de recherches m t orologiques, Meteo-France Centre National de Recherches Meteorologiques Meteo-France

Sulfate aerosol particles have strong scattering effect on the solar radiation transfer which results in increasing the planet albedo and, hence, tend to cool the earth-atmosphere system. Also, aerosols can act as the cloud condensation nuclei (CCN) which tend to increase the albedo of clouds and cool the global warming. The ARPEGE-Climat version 3 AGCM with FMR radiation scheme is used to estimate the direct and indirect radiative forcing of sulfate aerosols. For minimizing the uncertainties in assessing this kind of cooling effect, all kinds of factors are analyzed which have been mixed in the assessment process and may lead to the different results of the radiative forcing of aerosols. It is noticed that one of the uncertainties to assess the climate forcing of aerosols by GCM results from the different definition of radiative forcing that was used. In order to clarify this vague idea, the off-line case for considering no feedbacks and on-line case for including all the feedbacks have been used for assessment. The direct forcing of sulfate aerosols in off-line case is ?0.57 W/ m2 and ?0.38 W/ m2 for the clear sky and all sky respectively. The value of on-line case appears to be a little larger than that in off-line case chiefly due to the feedback of clouds. The indirect forcing of sulfate aerosols in off-line case is ?1.4 W/ m2 and ?1.0 W/ m2 in on-line case. The radiative forcing of sulfate aerosols has obvious regional characteristics. There is a larger negative radiative forcing over North America, Europe and East Asia. If the direct and indirect forcing are added together, it is enough to offset the positive radiative forcing induced by the greenhouse gases in these regions. Key words Radiative forcing - Feedback - Uncertainties - Sulfate aerosols

关键词： Radiative forcing Feedback Uncertainties Sulfate aerosols

GTR-Mediated Radial Import Directs Accumulation of Defensive Glucosinolates to Sulfur-Rich Cells in the Phloem Cap of Arabidopsis Inflorescence Stem

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Molecular Plant 2019年第11期12卷 1474-1484页

作者： Deyang Xu pascal Hunziker Olga Koroleva Andreas Blennow Christoph Crocoll Alexander Schulz Hussam Hassan Nour-Eldin Barbara Ann Halkier DynaMo Center Department of Plant and Environmental SciencesFaculty of ScienceUniversity of Copenhagen1871 Frederiksberg CDenmark Lonza Biologies Pic 228 Bath RoadSlough SL14DXUK Section for Plant Glycobiology Department of Plant and Environmental SciencesFaculty of ScienceUniversity of Copenhagen1871 Frederiksberg CDenmark

In the phloem cap region o i Arabidopsis plants,sulfur-rich cells(S-cells)accumulate>100 mM glucosinolates(GLS),but are biosynthetically *** source and route of S-cell-bound GLS remain *** this study,using single-cell sampling and scanning electron microscopy with energy-dispersive X-ray analysis we show that two GLS importers,NPF2.10/GTR1 and NPF2.11/GTR2,are critical for GLS accumulation in S-cells,although they are not localized in the *** of GLS levels in S-cells in multiple combinations of homo-and heterografts o lg t r l gtr2,biosynthetic null mutant and wild-type plants indicate that S-cells accumulate GLS via symplasmic connections either directly from neighboring biosynthetic cells or indirectly to non-neighboring cells expressing GTR1/*** sources and transport routes exist for different types of GLS,and vary depending on the position of S-cells in the inflorescence *** on these findings,we propose a model illustrating the GLS transport routes either directly from biosynthetic cells or via GTR-mediated import from apoplastic space radially into a symplasmic domain,wherein the S-cells are the ultimate ***,we observed accumulation of the cyanogenic glucoside defensive compounds in high-turgor cells in the phloem cap of Lotus japonicus,suggesting that storage of defensive compounds in high-turgor cells may be a general mechanism for chemical protection of the phloem cap.

关键词： Arabidopsis glucosinolate S-cell phloem cap xylem symplasmic transport

The sperm-interacting proteome in the bovine isthmus and ampulla during the periovulatory period

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Journal of Animal Science and Biotechnology 2023年第3期14卷 980-1000页

作者： Coline Mahe Regis Lavigne Emmanuelle Com Charles Pineau Aleksandra Maria Zlotkowska Guillaume Tsikis pascal Mermillod Jennifer Schoen Marie Saint-Dizier CNRS IFCEINRAEUniversite de ToursPRC37380 NouzillyFrance Univ Rennes InsermEHESPIrset(Institut de Recherche en SanteEnvironnement Et Travail)-UMR-S 1085F‑35000 RennesFrance Univ Rennes CNRSInsermBiosit UAR 3480 US_S 018Protim Core Facility35000 RennesFrance Institute of Reproductive Biology Leibniz Institute for Farm Animal BiologyFBNDummerstorfGermany Present Address:Department of Reproduction Biology Leibniz Institute for Zoo and Wildlife Research(IZW)BerlinGermany

Background Spermatozoa interact with oviduct secretions before fertilization in vivo but the molecular players of this dialog and underlying dynamics remain largely *** objectives were to identify an exhaustive list of sperm-interacting proteins(SIPs)in the bovine oviduct fluid and to evaluate the impact of the oviduct anatomical region(isthmus ***)and time relative to ovulation(pre-ovulatory ***-ovulatory)on SIPs number and *** Pools of oviduct fluid(OF)from the pre-ovulatory ampulla,pre-ovulatory isthmus,post-ovulatory ampulla,and post-ovulatory isthmus in the side of ovulation were collected from the ***-thawed bull sperm were incubated with OF or phosphate-buffered saline(control)for 60 min at 38.5℃.After protein extraction and digestion,sperm and OF samples were analyzed by nanoLC-MS/MS and label-free protein *** A quantitative comparison between proteins identified in sperm and OF samples(2333 and 2471 proteins,respectively)allowed for the identification of 245 *** highest number(187)were found in the pre-ovulatory isthmus,i.e.,time and place of the sperm *** total,41 SIPs(17%)were differentially abundant between stages in a given region or between regions at a given stage and 76 SIPs(31%)were identified in only one region×stage *** analysis of SIPs predicted roles in cell response to stress,regulation of cell motility,fertilization,and early embryo *** This study provides a comprehensive list of SIPs in the bovine oviduct and evidences dynamic spatiotemporal changes in sperm-oviduct interactions around ovulation ***,these data provide protein candidates to improve sperm conservation and in vitro fertilization media.

关键词： Ampulla Fallopian tube Interactome Isthmus Oviduct Ovulation Post-ovulatory Pre-ovulatory Proteomics Spermatozoa

NitroMAC：An instrument for the measurement of HONO and intercomparison with a long-path absorption photometer

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Journal of Environmental Sciences 2016年第2期28卷 105-113页

作者： Charbel Afif Corinne Jambert Vincent Michoud Aurélie Colomb Gregory Eyglunent Agnès Borbon Véronique Daele Jean-Francois Doussin pascal Perros Emissions Measurements and Modeling of the Atmosphere Laboratory EGFEM Unit Center for Analysis and Research Faculty of SciencesSaint Joseph University Beirut Lebanon Laboratoire Interuniversitaire des Systemes Atmospheriques (LISA) UMR7583 CNRS Universite Paris-Est-Creteil (UPEC) et Universite Paris Diderot (UPD) Institut Pierre Simon Laplace (IPSL) Creteil France Institut de Combustion Aerothermique Reactivite et Environnement CNRS Orleans France

Nitro MAC（French acronym for continuous atmospheric measurements of nitrogenous compounds） is an instrument which has been developed for the semi-continuous measurement of atmospheric nitrous acid（HONO）. This instrument relies on wet chemical sampling and detection using high performance liquid chromatography（HPLC）-visible absorption at540 nm. Sampling proceeds by dissolution of gaseous HONO in a phosphate buffer solution followed by derivatization with sulfanilamide/N-（1-naphthyl）-ethylenediamine. The performance of this instrument was found to be as follows： a detection limit of around 3 ppt with measurement uncertainty of 10% over an analysis time of 10 min. Intercomparison was made between the instrument and a long-path absorption photometer（LOPAP） during two experiments in different environments. First, air was sampled in a smog chamber with concentrations up to 18 ppb of nitrous acid. Nitro MAC and LOPAP measurements showed very good agreement. Then, in a second experiment, ambient air with HONO concentrations below250 ppt was sampled. While Nitro MAC showed its capability of measuring HONO in moderate and highly polluted environments, the intercomparison results in ambient air highlighted that corrections must be made for minor interferences when low concentrations are measured.

关键词： Atmospheric measurements Nitrous acid Sulfanilamide/N-(1-naphthyl)-ethylenediamine Long-path absorption photometer French acronym for continuous atmospheric measurements of nitrogenous compounds(NitroMAC)

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金属板件冲压过程的数值模拟

西南交通大学学报 1994年第5期29卷 500-505页

作者：柳葆生 pascal,B 西南交通大学机械工程研究所

本文介绍以大时间增量方法求解金属板件冲压成形数值模拟的原理及实施方式。讨论了与之相关具有接触和摩擦几何非线性问题的描述方法，并给出二维问题的算例。

关键词：冲压成形数值模拟金属板件

Effects of plane strain on inhomogeneous turbulence

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Science China Mathematics 1999年第2期42卷 154-161页

作者：张兆顺崔桂香许春晓 L.SHAO H.pascal J.P.Bertoglio LMFA UMR CNRS 5509 Ecole Centrale de Lyon Ecole Centrale de Lyon Ecully Ecully Ecully

The influence of the mean plane strain on the turbulence transportation is investigated by large eddy simulation (LES) in the shearless turbulence mixing layer. It is found that the mean strains enhance the turbulent fluctuations in the mixing region. Compression in the inhomogeneous direction can greatly increase the transport of turbulent kinetic energy by triple correlation terms, while stretching in the inhomogeneous direction decreases the turbulence transportation. The gradient diffusion models for turbulent transportation are evaluated and it is found that the inter-mittency consideration can improve the prediction ability of the gradient-type models for the triple correlation terms.

关键词： shearless turbulence mixing layer large eddy simulation.

Integrated Process for Production of Surfactin(III)Modeling of Adsorption Column

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Chinese Journal of Chemical Engineering 2011年第3期19卷 357-364页

作者： Ludovic Montastruc 刘涛 Iordan Nikov pascal Floquet Serge Domenech Laboratoire ProBioGEM EA 1026 Polytech'Lille State Key Laboratory of Chemical Engineering East China University of Science and Technology Laboratoire de Génie Chimique Z.A Basso Cambo5 rue Paulin Talabot

The study is focused on modeling of separation process and *** adsorption separation process is *** surfactin production process by Bacillus subtilis ATCC 21332 followed by surfactin adsorption in a fixed-bed column packed with commercial active carbon is studied in *** adsorption column achieves high surfactin recovery(94%)by up-flow methanol elution at 25°*** adsorption column is simulated with a complex one-dimensional plug flow dispersion model coupled with nonlinear adsorption equilibrium,based on the assumption that the adsorption of surfactin is monomolecular layer and no micelle is *** molecular diffusion coefficient of surfactin in water solution with electric neutrality is estimated to be 0.428×10 -5 cm 2 ·s -1 by molecular dynamics *** model developed can describe the complex interplay of adsorption kinetics,fluid dynamics,and mass-transfer phenomena based on the assumption of no radial temperature and concentration gradients,and is of adequate *** work involved in this paper is valuable for the optimization of the production process of surfactin.

关键词： surfactant adsorption mathematical modelling kinetics integrated process