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Microstructural and textural investigation of an Mg-Dy alloy after hot plane strain compression

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Journal of Magnesium and Alloys 2020年第4期8卷 1198-1207页

作者： Fairouze Guerza-Soualah Hiba Azzeddine Thierry Baudin anne-laure helbert Frangois Brisset Djamel Bradai Laboratory of Materials Physics Faculty of PhysicsUniversity of Sciences and Technology-Houari Boumediene(U.S.T.H.B.)P.O.Box 32El-AliaBab-EzzouarDZ-16111AlgiersAlgeria Faculty of Technology University of Mohamed BoudiafM'Sila 28000Algeria CNRS Institut de Chimie Moleculaire et des Materiaux d'OrsayUniversite Paris-Saclay91405 OrsayFrance

The microstructure and texture development in a Mg-0.41Dy(wt%)alloy after plane strain compression(PSC)at 300℃under a strain rate of 10^(-2)and 10^(-4)s^(-1),up a final true strain of—1.2 were investigated using electron backscatter diffraction(EBSD)and X-ray diffraction.At high strain rate of 10^(-2)s^(-1),the microstructure exhibited massive twins mainly{101^(-)2}extension,{1011}contraction and{101^(-)3}-{101^(-)2}double twin due to the random texture of the as-cast alloy.Meanwhile,at a low strain rate of 10^(-4)s^(-1),the microstructure was characterized by dynamic recrystallization at the{101^(-)2}extension,(101^(-)1)contraction twins and grain boundaries.Twin dynamic recrystallization(TDRX),rotational dynamic recrystallization(RDRX)and discontinuous dynamic recrystallization(DDRX)were the main mechanisms responsible for the formation of recrystallized grains.The texture was characterized by the formation of three fibers:basal,//CD and//CD where CD is the compression direction.Moreover,the texture was less sensitive to the deformation conditions since the recrystallized grains showed the same orientation than twins.The changes of the mechanical properties of the alloy were ascribed to the resulting microstructure due to the twinning and dynamic recrystallization.

关键词： Dynamic recrystallization PSC Mg-Dy alloy Texture Twinning.

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Erratum to:Microstructure and texture evolution of nonoriented silicon steel during the punching process

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International Journal of Minerals,Metallurgy and Materials 2023年第6期30卷 1225-1225页

The original online version of this article unfortunately contained a mistake.The author’s name in the original online version is incorrect,which is:Xiang Fang,Wei Wang,François Brisset,anne-laure Helberg,and Thierry... 详细信息

关键词： Microstructure steel evolution

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Angular Dependence of the Second Harmonic Generation Induced by Femtosecond Laser Irradiation in Silica-Based Glasses:Variation with Writing Speed and Pulse Energy

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World Journal of Nano Science and Engineering 2015年第3期5卷 96-106页

作者： Jing Cao Bertrand Poumellec Fran?ois Brisset anne-laure helbert Matthieu Lancry Institut de Chimie Moléculaire et des Matériaux d’Orsay(ICMMO) CNRS-UniversitéParis SudUniversitéParis SaclayBat.420Campus Orsay91405 OrsayFrance

To control second harmonic generation (SHG) in silica-based glasses is crucial for fabricating photonic devices, such as frequency doubling waveguides. Here, we investigated SHG of laser induced nonlinear optical crystals in silica-based glasses, according to writing speed and pulse energy. We observed two regions with different probing laser polarization angular dependence: a) a well-defined cosine-like curve with period of 180° at low pulse energy (0.8 μJ) whatever the writing speed or at high pulse energy (1.4 μJ) with high writing speed (25 μm/s). This is accounted for by a well-defined texture for the nano crystals with their polar axis oriented perpendicular to the writing laser polarization;and b) a double cosine-like curve revealing a second texture of the crystals at high pulse energy (1.4 μJ) with low writing speed (5 μm/s) and with the polar axis oriented closer parallel to the writing laser polarization. Therefore, a SHG dependence on probing laser polarization angle may show high contrast by a correct choice of the writing speed and pulse energy. These results pave the way for elaboration of nonlinear optical devices.

关键词： Nonlinear Optical Crystal Glass Ceramics Direct Writing Ultrafast Processes Waveguide

Texture of Rotary-Friction-Welded from Dissimilar Medium Carbon Steels

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World Journal of Condensed Matter Physics 2020年第4期10卷 178-190页

作者： Zakaria Boumerzoug Elena Priymak Anna Stepanchukova anne-laure helbert François Brisset Thierry Baudin Department of Mechanical Engineering LMSM University of Biskra Biskra Algeria Orenburg State University Orenburg Russia ZBO Drill Industries Orenburg Russia Université Paris-Saclay CNRS Institut de chimie moléculaire et des matériaux d’Orsay Orsay France

The purpose of the present study was to investigate the texture in dissimilar medium carbon steels welded by rotary friction technique. The Electron Backscatter Diffraction (EBSD) technique was the main technique used to investigate the effect of welding on grain size and grain crystallographic orientation in the welded joint. Moreover, the effect of isothermal heat treatment at 600°C on welded joint has been studied knowing that this annealing allows to decrease the residual stresses. EBSD results revealed different subzones in welded joint. The texture in the weld is essentially composed of three components: Goss {110} , Rotated Cube {100} , and Rotated Goss {110} orientation. The heat treatments applied on welded material had a slight effect on texture and grain size.

关键词： Texture Rotary Friction Welding Medium Carbon Steels

Genomic profile concordance between pancreatic cyst fluid and neoplastic tissue

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World Journal of Gastroenterology 2019年第36期25卷 5530-5542页

作者： Arthur Laquière Arnaud Lagarde Bertrand Napoléon Raphael Bourdariat Alexandre Atkinson Gianfranco Donatelli Bernard Pol laurence Lecomte laurence Curel Romina Urena-Campos Thierry helbert Vincent Valantin Francois Mithieux Jean Pascal Buono Philippe Grandval Sylviane Olschwang Department of Gastroenterology Saint Joseph Hospital Marseille 13008 France AP-HM Timone Hospital Marseille 13005 France RGDS Clairval Hospital Marseille 13009 France Aix-Marseille Univ INSERM MMG Marseille 13385 France AP-HM Conception Hospital Marseille 13385 France RGDS Jean Mermoz Hospital Lyon 69008 France RGDS Les Peupliers Hospital Paris 75013 France Department of Digestive Surgery Saint-Joseph Hospital Marseille 13008 France Department of Clinical Research Saint Joseph Hospital Marseille 13008 France European Hospital Marseille 13003 France Pathological Anatomy and Cytology MEDIPATH Eguilles 13510 France

BACKGROUND DNA mutational analysis of pancreatic cystic fluid (CF) is a useful adjunct to the evaluation of pancreatic cysts. KRAS/GNAS or RAF/PTPRD/CTNNB1/RNF43 mutations are highly specific to precancerous or advanced neoplasia. Several studies recently demonstrated the ability of next-generation sequencing (NGS)analysis to detect DNA mutations in pancreatic CF, but few studies have performed a systematic comparative analysis between pancreatic CF and neoplastic surgical tissue (NT). The value of CF-NGS analysis indicators for determining surgical resection necessitates evaluation. AIM To confirm whether CF genomic profiles are a reliable malignancy predictor by comparing NGS mutational analyses of CF and NT. METHODS Patients requiring surgery for high-risk pancreatic cysts were included in a multicenter prospective pilot study. DNA from CF (collected by endoscopic ultrasound-guided fine needle aspiration (known as EUS-FNA)) and NT (collected by surgery) were analyzed by NGS. The primary objective was to compare the mutation profiles of paired DNA samples. The secondary objective was to correlate the presence of specific mutations (KRAS/GNAS, RAF/ PTPRD/CTNNB1/RNF43/POLD1/TP53) with a final cancer diagnosis. Sensitivity and specificity were also evaluated. RESULTS Between December 2016 and October 2017, 20 patients were included in this pilot study. Surgery was delayed for 3 patients. Concordant CF-NT genotypes were found in 15/17 paired DNA, with a higher proportion of mutated alleles in CF than in NT. NGS was possible for all pancreatic CF collected by EUS-FNA. In 2 cases, the presence of a KRAS/GNAS mutation was discordant between CF and NT. No mutations were found in 3 patients with NT or pancreatic cysts with high-grade dysplasia. The sensitivity and specificity of KRAS/GNAS mutations in CF to predict an appropriate indication for surgical resection were 0.78 and 0.62, respectively. The sensitivity and specificity of RAF/PTPRD/CTNNB1 /RNF43/POLD1/TP53 mutations in CF were 0.55 and 1.0, respectively. CONCLU

关键词： Pancreatic cancer Pancreatic cystic neoplasms Pancreatic adenocarcinoma Malignancy prediction Neoplastic surgical tissue Pancreatic cystic fluid Molecular analysis Next-generation sequencing DNA mutations

Establishing the presence or absence of chronic kidney disease:Uses and limitations of formulas estimating the glomerular filtration rate

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World Journal of Methodology 2017年第3期7卷 73-92页

作者： Ahmed Alaini Deepak Malhotra helbert Rondon-Berrios Christos P Argyropoulos Zeid J Khitan Dominic SC Raj Mark Rohrscheib Joseph I Shapiro Antonios H Tzamaloukas Division of Nephrology Department of MedicineUniversity of New Mexico School of Medicine Division of Nephrology Department of MedicineUniversity of Toledo School of Medicine Renal and Electrolyte Division Department of MedicineUniversity of Pittsburgh School of Medicine Division of Nephrology Department of MedicineJoan C. Edwards School of Medicine Division of Nephrology Department of MedicineGeorge Washington University Marshall University Joan C. Edwards School of Medicine Nephrology Section Medicine ServiceRaymond G. Murphy VA Medical Center Department of Medicine University of New Mexico School of Medicine

The development of formulas estimating glomerular filtration rate(eG FR) from serum creatinine and cystatin C and accounting for certain variables affecting the production rate of these biomarkers, including ethnicity, gender and age, has led to the current scheme of diagnosing and staging chronic kidney disease(CKD),which is based on e GFR values and albuminuria.This scheme has been applied extensively in various populations and has led to the current estimates of prevalence of CKD. In addition, this scheme is applied in clinical studies evaluating the risks of CKD and the efficacy of various interventions directed towards improving its course. Disagreements between creatinine-based and cystatin-based e GFR values and between e GFR values and measured GFR have been reported in various cohorts. These disagreements are the consequence of variations in the rate of production and in factors, other than GFR, affecting the rate of removal of creatinine and cystatin C. The disagreements create limitations for all e GFR formulas developed so far. The main limitations are low sensitivity in detecting early CKD in several subjects, e.g., those with hyperfiltration, and poor prediction of the course of CKD. Research efforts in CKD are currently directed towards identification of biomarkers that are better indices of GFR than the current biomarkers and,particularly, biomarkers of early renal tissue injury.

关键词： Chronic kidney disease Serum creatinine Creatinine clearance Creatinine excretion Estimated glomerular filtration rate Cystatin C Renal imaging Hyperfiltration Biomarkers of chronic kidney disease

Hypertonicity:Clinical entities,manifestations and treatment

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World Journal of Nephrology 2017年第1期6卷 1-13页

作者： helbert Rondon-Berrios Christos Argyropoulos Todd S Ing Dominic S Raj Deepak Malhotra Emmanuel I Agaba Mark Rohrscheib Zeid J Khitan Glen H Murata Joseph I Shapiro Antonios H Tzamaloukas Renal-Electrolyte Division Department of MedicineUniversity of Pittsburgh School of MedicinePittsburghPA 15260United States Division of Nephrology Department of MedicineUniversity of New Mexico School of MedicineAlbuquerqueNM 87131United States Department of Medicine Strich School of MedicineLoyola University ChicagoMaywoodIL 60153United States Division of Nephrology Department of MedicineGeorge Washington UniversityWashingtonDC 20037United States Division of Nephrology Department of MedicineSchool of MedicineUniversity of ToledoToledoOH 43614-5809United States Division of Nephrology Department of MedicineJos University Teaching HospitalJosPlateau State 930001Nigeria Division of Nephrology Department of MedicineSchool of MedicineMarshall University Joan C.EdwardsHuntingtonWV 25701United States Informatics Section Medicine ServiceRaymond G.Murphy Veterans Affairs Medical CenterAlbuquerqueNM 78108United States Department of Medicine University of New Mexico School of MedicineAlbuquerqueNM 78108United States Marshall University Joan C.Edwards School of Medicine HuntingtonWV 25701United States Section of Nephrology Medicine Service(111C)Raymond G.Murphy Veterans Affairs Medical CenterAlbuquerqueNM 78108United States

Hypertonicity causes severe clinical manifestations and is associated with mortality and severe short-term and longterm neurological sequelae. The main clinical syndromes of hypertonicity are hypernatremia and hyperglycemia.Hypernatremia results from relative excess of body sodium over body water. Loss of water in excess of intake,gain of sodium salts in excess of losses or a combination of the two are the main mechanisms of hypernatremia.Hypernatremia can be hypervolemic,euvolemic or hypovolemic. The management of hypernatremia addresses both a quantitative replacement of water and,if present,sodium deficit,and correction of the underlying pathophysiologic process that led to hypernatremia.Hypertonicity in hyperglycemia has two components,solute gain secondary to glucose accumulation in the extracellular compartment and water loss through hyperglycemic osmotic diuresis in excess of the losses of sodium and potassium. Differentiating between these two components of hypertonicity has major therapeutic implications because the first component will be reversed simply by normalization of serum glucose concentration while the second component will require hypotonic fluid replacement. An estimate of the magnitude of the relative water deficit secondary to osmotic diuresis is obtained by the corrected sodium concentration,which represents a calculated value of the serum sodium concentration that would result from reduction of the serum glucose concentration to a normal level.

关键词：渗血症高血糖治疗方法临床分析

组成对抗蚀剂干蚀刻敏感度的影响——乙烯基聚合物与光致抗蚀剂

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电子元件与材料 1986年第5期 43-49页

作者： J.N.helbert ,M.A.Schmidt ,江璐霞

测定了一组乙烯基聚合物抗蚀剂和光致抗蚀剂的等离子体和活性离子蚀刻速率,以及离子铣蚀刻速率;并发现在合成中改变乙烯侧基取代基或改变光致抗蚀剂等20多种因素都会影响蚀刻速率。观察到含有重键及不饱和侧基的乙烯基聚合物抗蚀剂,以... 详细信息

测定了一组乙烯基聚合物抗蚀剂和光致抗蚀剂的等离子体和活性离子蚀刻速率,以及离子铣蚀刻速率;并发现在合成中改变乙烯侧基取代基或改变光致抗蚀剂等20多种因素都会影响蚀刻速率。观察到含有重键及不饱和侧基的乙烯基聚合物抗蚀剂,以及负性印刷体系具有低的蚀刻速率及较好的蚀刻适应性。虽然有二三种乙烯基体系聚合物确实有很好的性能,但光致抗蚀剂体系一般都具有更好的蚀刻适应性。与聚甲基丙烯酸甲酯或SiO2相比较,除了负性光致抗蚀剂外,乙烯基聚合物的蚀刻选择性和蚀刻方位对三种蚀刻技术都是相当稳定的。

关键词：聚合物等离子体蚀刻蚀刻速率大分子化合物等离子刻蚀抗蚀剂马丁烯酸甲基丙烯酸敏感度

Inductors of Resistance and Their Role in Photosynthesis and Antioxidant System Activity of Coffee Seedlings

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American Journal of Plant Sciences 2014年第25期5卷 3710-3716页

作者： Luiz Henrique Monteiro Fernandes helbert Rezende de Oliveira Silveira Kamila Rezende Dázio de Souza Mário Lúcio Vilela de Resende José Donizeti Alves Department of Plant Pathology Federal University of Lavras—UFLA Lavras Brazil Agricultural Reasearch Company of Minas Gerais—EPAMIG Campus of Federal University of Lavras—UFLA Lavras Brazil Department of Biology Federal University of Lavras—UFLA Lavras Brazil

We investigated the effects of formulations based on phosphite products on gas exchange and activity of antioxidant enzymes in coffee plants. Seedlings of the Mundo Novo cultivar were submitted to various treatments composed of different formulations of with potassium phosphite (ADB 120), manganese phosphite (Reforce Mn), and fungicide (PrioriXtra®). For coffee seedlings, the combination of potassium phosphite and citrus by-products, isolated or in a combination with other products elicited the antioxidant system. Besides the high activity of antioxidant enzymes, the photosynthetic rates were higher than other treatments. The better performance of coffee seedlings treated with those formulations occurred even in absence of pathogens.

关键词： Coffea arabica Superoxide Dismutase Ascorbate Peroxidase Catalase