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Collagen and Leather 2023年第2期5卷 51-66页

作者： mónica Gisel Arellano-Sánchez Juliette Vievard Lamia moufarrej Christine Devouge-Boyer marie Hubert-Roux Carlos Afonso mélanie mignot COBRA UmR CNRS 6014 INSANormandie UniversityUNIROUENAvenue de l'Université76800 Saint-Etienne-du-RouvrayFrance COBRA UMR CNRS 6014IRCOFNormandie UniversityUNIROUEN76821 Mont-Saint-Aignan CedexFrance

In the present work,a comparative study of analytical methods for the simultaneous and quantitative determination of trivalent and hexavalent chromium is *** the analysis by ion chromatography-inductively coupled plasma-mass spectrometry,two different columns were tested,as well as different mobile phases and different pH of the *** optimized analytical method permitted the separation of Cr(Ⅲ)and Cr(Ⅵ)using 75 mmol/L NH_(4)NO_(3)pH 3 as chromatographic *** method was validated and applied to real samples,allowing the determination of both species simultaneously,even when there is a huge difference of concentration between Cr(Ⅲ)and Cr(Ⅵ).Limit of detection and limit of quantification for Cr(Ⅲ)were found to be 0.016 and 0.054μg/L(0.3 and 1.1μg/kg),respectively,and for Cr(Ⅵ)0.13 and 0.43μg/L(7 and 22μg/kg),*** species interconversions were monitored through the use of chromium isotopic standards,which confirmed that the optimized methodology preserves chromium speciation during extraction and ***-transform ion cyclotron resonance-mass spectrometry permitted the structure elucidation of the complex formed during ethylenediaminetetraacetic acid extraction.

关键词： Chromium speciation Tanned leather Interconversions Ion chromatography Inductively coupled plasmamass spectrometry Fourier-transform ion cyclotron resonance mass spectrometry

Quantitative extraction of chromium Ⅵ and Ⅲ from tanned leather: a comparative study of pretreatment methods

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Journal of Leather Science and Engineering 2021年第1期3卷 337-349页

作者： monica Gisel Arellano‑Sanchez Christine Devouge‑Boyer marie Hubert‑Roux Carlos Afonso melanie mignot UNIROUEN COBRA UMR CNRS 6014INSANormandie UniversityAvenue de l’Universite76800 Saint‑Etienne‑du‑RouvrayFrance UNIROUEN COBRAUMR CNRS 6014IRCOFNormandie University76821 Mont‑Saint‑Aignan CedexFrance

In this study,seven pretreatment methods for chromium speciation in tanned leather were evaluated:acidic miner‑alization,ethylenediaminetetraacetic acid(EDTA)extraction,diethylenetriaminepentaacetic acid(DTPA)extraction,alkaline extraction(NH 4 OH),ammonium nitrate extraction(NH 4 NO 3),water extraction,and phosphate buffer extrac‑*** mineralization permitted the decomposition of the organic matter and ensured the complete digestion of leathers,giving access to the total content of chromium in each sample using inductively coupled plasma‑atomic emission spectrometry(ICP‑AES).From all the extractant media tested,EDTA proved to be the most efficient,allowing the extraction of Cr(VI)and Cr(III)as a Cr(III)‑EDTA complex,*** validation is presented for EDTA extraction and direct *** the EDTA extraction,method detection limit(mDL)and method quantifica‑tion limit(mQL)for total Cr in leather were 3.4 ppb and 11.2 ppb(µg of total Cr per L of extraction solution),respec‑*** to the lack of leather certified reference materials(CRms)for Cr(VI),accuracy was evaluated by spiking leather samples with a Cr(VI)*** spike recovery of EDTA microwave assisted extraction ranged from 91.0 to 108.6%.Interday precision was also evaluated and all variation coefficients were below 5%,for both mineralization and EDTA *** article provides an efficient procedure to extract quantitatively chromium from leather,while maintaining the speciation,which can be further followed by ion chromatography‑inductively coupled plasma‑mass spectrometry(IC‑ICP‑mS).

关键词： Hexavalent chromium Speciation Tanned leather Sample pretreatment EDTA complexation Inductively coupled plasma

Cognition and the brain of brood parasitic cowbirds

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Integrative Zoology 2019年第2期14卷 145-157页

作者： David F.SHERRY mélanie F.GUIGUENO Department of Psychology Western University LondonOntario Department of Natural Resource Sciences McGill UniversityMontrealQuebecCanada

Cowbirds are brood *** lay their eggs in the nests of other species,which then incubate the cowbird eggs and raise the young *** and returning to heterospecific nests presents cowbirds with several cognitive *** some species,such as brown-headed cowbirds(molothrus ater),females but not males search for and remember the locations of potential host *** describe recent research on sex differences in cognition and the hippocampus associated with this sex difference in search for host *** brown-headed cowbirds perform better than males on some,but not all,tests of spatial memory and females show a pattern of adult hippocampal neurogenesis not found in males or in closely related non-parasitic *** of the apparent specialization of the hippocampus,brown-headed cowbirds may be a good model in which to examine spatial information processing in the avian hippocampus and we also describe recent research on the spatial response properties of brown-headed cowbird hippocampal neurons.

关键词： adult neurogenesis brood parasites cowbirds hippocampus sex differences spatial memory

The genetic basis of grape and wine aroma

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Horticulture Research 2019年第1期6卷 716-739页

作者： Jerry Lin mélanie massonnet Dario Cantu Department of Viticulture and Enology University of California DavisOne Shields AveDavisCA 95616USA

The grape is one of the oldest and most important horticultural *** and wine aroma has long been of cultural and scientific *** diverse compound classes comprising aroma result from multiple biosynthetic *** fairly recently have researchers begun to elucidate the genetic mechanisms behind the biosynthesis and metabolism of grape volatile *** review summarizes current findings regarding the genetic bases of grape and wine aroma with an aim towards highlighting areas in need of further *** the literature,we compiled a list of functionally characterized genes involved in berry aroma biosynthesis and present them with their corresponding annotation in the grape reference genome.

关键词： Grape aroma metabolism

Paraneoplastic leukemoid reaction in pancreatic cancer: A case report

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World Journal of Gastrointestinal Oncology 2015年第10期7卷 259-262页

作者： mélanie Dos Santos Karine Bouhier manh-Thong Dao Department of Gastroenterology CHU de Caen

Paraneoplastic leukemoid reaction is a rare syndrome defined by a leukocyte count exceeding 50 Giga/Liter(G/L), mostly described with progressive lung or renal carcinoma. We report a case of a 68-year-old man with recurrent pancreatic carcinoma presenting a leukemoid reaction with a white blood cell count of 63.87 G/L without identified infectious, iatrogenic or hematologic causes. His overall condition quickly degraded and he died three weeks after the discovery of the leukemoid reaction. This is the first case in French literature of leukemoid reaction in a patient with pancreatic carcinoma with poor prognostic value.

关键词： Leukemoid reaction Pancreatic neoplasms Paraneopla

Screening polypectomy rates below quality benchmarks:A prospective study

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World Journal of Gastroenterology 2014年第43期20卷 16300-16305页

作者： maida J Sewitch mengzhu Jiang mélanie Fon Sing Alan Barkun Lawrence Joseph Department of medicine Mc-Gill UniversityMontréalQuébec H3G 1Y6Canada Division of Clinical Epidemiology Research Institute of the Mc Gill University Health CentreMontréalQuébec H3A 1A1Canada Department of Epidemiology Biostatistics and Occupational HealthMc Gill UniversityMontréalQuébec H3A 1A2Canada

AIm: To estimate and compare sex-specific screening polypectomy rates to quality benchmarks of 40% in men and 30% in women.

关键词： Benchmarking Colonoscopy Colorectal cancer Quality assurance Screening

Optical coherence tomography angiography at the acute phase of optic disc edema

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Eye and Vision 2018年第1期5卷 144-150页

作者： marie-Bénédicte Rougier mélanie Le Goff Jean-François Korobelnik Service d’Ophtalmologie CHU de BordeauxBordeauxFrance Bordeaux Population Health Research Center Team LEHAUniversity BordeauxINSERMUMR 1219F-33000 BordeauxFrance

Background:The differential diagnosis of optic disc edema at the acute phase can be *** angiography(OCTA)is a new technology allowing the visualization of the peripapillary vascular network and optic disc *** peripapillary network alterations of glaucoma and chronic non-arteritic anterior ischemic optic neuropathy(NAION)were ***,no OCTA studies on acute optic disc edema from various *** aim of this project was to use OCTA to demonstrate the vascular changes the optic nerve head of various types of optic disc edema at the acute ***:In this retrospective study,patients with non-arteritic anterior ischemic optic neuropathy(NAION),papillitis or papilledema were *** patient was imaged using the AngioPlex^(Tm)CIRRUS^(Tm)HD-OCT device(model 5000,Carl Zeiss meditec,Inc.,Dublin,USA)with a scanning area of 6×6 mm^(2) centered on the optic disc.A morphological analysis of the peripapillary network was *** some patients with unilateral optic disc edema,a quantitative analysis was performed using a swept-source OCT-A system(PLEX®Elite 9000,Carl Zeiss meditec,Inc.,Dublin,USA).Vessel perfusion density and flux index of the peripapillary area were ***:Eight eyes with NAION(4 patients),12 eyes with papillitis(6 patients)and 25 eyes with papilledema(13 patients)were *** apparent disappearance or moderate pattern alteration of the peripapillary capillary vessels were observed in patients with NAION or papillitis,*** papilledema,the capillaries at the surface of the optic disc were dilated and tortuous,but no peripapillary network pattern changes were *** quantitative analysis did not show any difference of peripapillary network between NAION and healthy *** papillitis,the flux index was higher in inflammatory eyes compared to the healthy eyes in average(p=0.03).Conclusion:At the acute phase,the morphological analysis of OCT-A appeared to be more useful than the q

关键词： Optical coherence tomography angiography Optic nerve head Edema NAION microvascular network And morphology

Nonlinear forced vibration in a subcritical regime of a porous functionally graded pipe conveying fluid with a retaining clip

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Applied mathematics and mechanics(English Edition) 2025年第1期46卷 101-122页

作者： m.GHOLAmI m.EFTEKHARI Department of mechanical Engineering Shahid Bahonar University of Kerman

This study examines the nonlinear behaviors of a clamped-clamped porous pipe made of a functionally graded material(FGm) that conveys fluids and is equipped with a retaining clip, focusing on primary resonance and subcritical dynamics. The nonlinear governing equations for the FGm pipe are derived by the extended Hamilton's principle, and subsequently discretized through the application of the Galerkin *** direct method of multi-scales is then used to solve the derived equations. A thorough analysis of various parameters, including the clip stiffness, the power-law index, the porosity, and the clip location, is conducted to gain a comprehensive understanding of the system's nonlinear dynamics. Through the analysis of the first natural frequency, the study highlights the influence of the flow velocity and the clip stiffness, while the comparisons with metallic pipes emphasize the role of FGm composition. The examination of the forced response curves reveals saddle-node bifurcations and their dependence on parameters such as the detuning parameter and the power-law index, offering valuable insights into the system's nonlinear resonant behavior. Furthermore, the frequency-response curves illustrate the hardening nonlinearities influenced by factors such as the porosity and the clip stiffness, revealing nuanced effects on the system response and resonance characteristics. This comprehensive analysis enhances the understanding of nonlinear behaviors in FGm porous pipes with a retaining clip, providing key insights for practical engineering applications in system design and optimization.

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Neurogenesis dynamics in the olfactory bulb:deciphering circuitry organization, function, and adaptive plasticity

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Neural Regeneration Research 2025年第6期20卷 1565-1581页

作者： moawiah m.Naffaa Department of Psychology and Neuroscience Duke UniversityDurhamNCUSA Department of Cell Biology Duke University School of MedicineDurhamNCUSA

Adult neurogenesis persists after birth in the subventricular zone, with new neurons migrating to the granule cell layer and glomerular layers of the olfactory bulb, where they integrate into existing circuitry as inhibitory interneurons. The generation of these new neurons in the olfactory bulb supports both structural and functional plasticity, aiding in circuit remodeling triggered by memory and learning processes. However, the presence of these neurons, coupled with the cellular diversity within the olfactory bulb, presents an ongoing challenge in understanding its network organization and function. moreover,the continuous integration of new neurons in the olfactory bulb plays a pivotal role in regulating olfactory information processing. This adaptive process responds to changes in epithelial composition and contributes to the formation of olfactory memories by modulating cellular connectivity within the olfactory bulb and interacting intricately with higher-order brain regions. The role of adult neurogenesis in olfactory bulb functions remains a topic of debate. Nevertheless, the functionality of the olfactory bulb is intricately linked to the organization of granule cells around mitral and tufted cells. This organizational pattern significantly impacts output, network behavior, and synaptic plasticity, which are crucial for olfactory perception and memory. Additionally, this organization is further shaped by axon terminals originating from cortical and subcortical regions. Despite the crucial role of olfactory bulb in brain functions and behaviors related to olfaction, these complex and highly interconnected processes have not been comprehensively studied as a whole. Therefore, this manuscript aims to discuss our current understanding and explore how neural plasticity and olfactory neurogenesis contribute to enhancing the adaptability of the olfactory system. These mechanisms are thought to support olfactory learning and memory, potentially through increased

关键词： network adaptability neurogenesis neuronal communication olfactory bulb olfactory learning olfactory memory synaptic plasticity

A novel regulatory region controls IgH locus transcription and switch recombination to a subset of isotypes

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Cellular & molecular Immunology 2019年第11期16卷 887-889页

作者： Rocío Amoretti-Villa mélanie Rogier Isabelle Robert Vincent Heyer Bernardo Reina-San-martin Institut de Génétique et de Biologie moléculaire et Cellulaire(IGBmC) IllkirchFrance Institut National de la Santéet de la Recherche médicale(INSERm) U1258IllkirchFrance Centre National de la Recherche Scientifique(CNRS) UMR7104IllkirchFrance Universitéde Strasbourg IllkirchFrance

Class switch recombination(CSR)occurs at the IgH locus and replaces the immunoglobulin(Ig)isotype expressed from Igm to IgG,IgE or IgA,endowing the B cell receptor with novel effector *** is triggered by activation-induced cytidine deaminase(AID),1 an enzyme that deaminates cytosines to uracils in single-stranded DNA exposed by *** distinct antibody isotypes are encoded in the IgH locus in individual transcription units composed of a cytokine-inducible promoter,an intronic exon,and a switch region(Sx),followed by the exons encoding the constant region(Cx)(Fig.S1a).During CSR,the choice of recombination to a particular isotype is determined by the stimulation-dependent activation of specific promoters,triggering the generation of noncoding germline transcripts(GLTs).2 Thus far,the transcriptional regulation of the IgH locus is known to be controlled by the Eμenhancer,located downstream of the variable region and upstream of the donor switch region(Sμ),and the 3′regulatory region(3′RR)super-enhancer located downstream of Cα.

关键词： IgH stimulation replace