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Vitamin d and clinically isolated syndrome

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中华物理医学与康复杂志 2016年第4期38卷 258-258页

作者： Mowry EM pelletier d Gao Z

BACKGROUNd ANd OBJECTIVE Previous studies have demonstrated that levels of 25-hydroxyvitamin d are associated with inflammatory activity among patients with multiple sclerosis (MS). As the loss of gray matter volume predicts long-term disability among patients with MS, this study was designed to determine any association between 25-hydroxyvitamin d levels among patients with clinically isolated syndrome (CIS) and imaging measures of *** data were obtained from subjects in the STAy CIS trial, a randomized study of atorvastatin in patients with recent CIS, used to assess the association of 25-hydroxyvitamin d levels with imaging measures thought to reflect neurodegeneration. All subjects were evaluated clinically and by brain MRI at baseline and at months three, six, nine, and 12. The primary endpoint was the development of at least one MS relapse or at least three new T2 lesions on brain MRI at month 12. The data were reviewed for the relationship between 25-hydroxy vitamin d levels and clinical and MRI measures of inflammatory *** Of the 65 patients included in this study, 55% met the composite inflammatory endpoint, while 29% had a second attack during the follow-up period. Every 25 nmol/l higher 25-hydroxyvitamin d level was associated with a 7.8 mL higher gray matter volume (P=0.025). A trend was noted for an inverse association between vitamin d levels and the composite endpoint of at least three new brain T2 lesions or at least one relapse within the first 12 *** This study of patients with early CIS found that increased levels of 25-hydroxyvitamin d are associated with preserved gray matter volume.

关键词：维生素d 临床分离综合征神经退行性疾病多发性硬化体积损失患者影像学

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定量模拟地球地表过程

国外科技新书评介 2009年第5期 19-20页

作者： Joe d．pelletier

当前，受数值模拟、地质年代学以及遥感等方面一些新出现的技术影响，地貌学正在经历一场新一轮的复兴。数值模拟上所取得的进步使得建模地球地表过程及其在大尺度的时空范围与气候、构造地质之间的反馈过程成为可能。根据宇宙射线进行... 详细信息

当前，受数值模拟、地质年代学以及遥感等方面一些新出现的技术影响，地貌学正在经历一场新一轮的复兴。数值模拟上所取得的进步使得建模地球地表过程及其在大尺度的时空范围与气候、构造地质之间的反馈过程成为可能。根据宇宙射线进行测年以及其他的地质测年技术也为地貌形成速率及形成年代的测算提供了新的契机。与此同时，

关键词：地表过程定量模拟地球地质年代学测年技术数值模拟时空范围构造地质

Investigation into a practical approach and application of cotton fiber elongation

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Journal of Cotton Research 2023年第1期6卷 13-24页

作者： dELHOM Christopher d. WANJURA John d. pelletier Mathew G. HOLT Gregory A. HEQUET Eric F. USdA-ARS New OrleansLA 70124USA USdA-ARS LubbockTX 79403USA Texas Tech University LubbockTX 79409USA

Background The strength of cotton fiber has been extensively studied and significantly improved through selec-tive breeding,but fiber elongation has largely been ignored,even though elongation contributes to determining the energy needed to break *** developments to calibrate the high volume instrument(HVI)for elongation has renewed interest in ***,it is not understood how best to utilize yet another fiber property which has the potential to add to the complexity of fiber *** explore a practical approach to applying elongation,cot-ton samples were tested using single fiber methods,the Stelometer,and the *** of strength,elongation,and combined properties such as modulus were *** HVI testing was shown to be sensitive enough to characterize elongation differences but unlike single fiber testing it was unable to capture within-sample *** bundle testing,like Stelometer and HVI was shown to reduce bias due to fiber *** The use of secant modulus,an intrinsic material property,allowed for one value to represent both strength and *** modulus was shown to contain more useful information than either elongation or ***-to-break was shown to be more influenced by a specific value of breaking force or elongation rather than the intrinsic behavior of the sample being *** the influence of genetics and environment on elongation,and its interaction with other fiber properties,requires additional *** modulus,by combining strength and elongation into one value,shows the potential to incorporate elongation values into fiber characteriza-tion without increasing the complexity of current fiber selection processes.

关键词： Cotton Elongation Tenacity Work-to-break ModulusBackground

Analysis of the anelastic deformation of high-entropy Pd_(20)Pt_(20)Cu_(20)Ni_(20)P_(20) metallic glass under stress relaxation and recovery

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Journal of Materials Science & Technology 2022年第12期107卷 82-91页

作者： Y.J.duan L.T.Zhang T.Wada H.Kato E.Pineda d.Crespo J.M.pelletier J.C.Qiao School of Mechanics Civil Engineering and ArchitectureNorthwestern Polytechnical UniversityXi’an 710072China department of Physics Institute of Energy TechnologiesUniversitat Politècnica de CatalunyaBarcelona 08019Spain Institute for Materials Research Tohoku UniversitySendai 980-8577Japan Universitéde Lyon MATEISUMR CNRS5510Bat.B.PascalINSA-LyonF-69621 Villeurbanne CedexFrance

The anelastic deformation behavior of Pd_(20)Pt_(20)Cu_(20)Ni_(20)P_(20) high-entropy metallic glass was probed by monitoring the stress relaxation and recovery processes. The stress relaxation under consecutive strain steps can be described by the Kohlrausch-Williams-Watts(KWW) function. In addition, considering a hierarchy of relaxation processes related to the structural heterogeneity, a constitutive model is proposed in order to describe the whole process of stress relaxation and determine the contribution of different time scales. Moreover, a crossover from stochastic activation to percolation of flow defects with the ultimate strain can be observed during stress relaxation process. The anelastic recovery process after a strain step is studied as a function of the initial strain level and characterized by means of a direct spectrum analysis. The peaks in the recovery time-spectra revealed the evolution of flow defects in Pd_(20)Pt_(20)Cu_(20)Ni_(20)P_(20) high-entropy metallic glass. The understanding of the atomic free-volume zones effect and the anelastic deformation provides important insight into how atomic structural features affect the deformation behavior of high-entropy metallic glasses, and may provide a new avenue into the improvement of their mechanical properties.

关键词： High-entropy metallic glass Stress relaxation Anelastic deformation Flow defects Free-volume zones

Secondary relaxation and dynamic heterogeneity in metallic glasses：A brief review

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Chinese Physics B 2017年第1期26卷 32-41页

作者：乔吉超 Q Wang d Crespo 杨勇 J M pelletier School of Mechanics Civil Engineering and Architecture Northwestern Polytechnical University Xi'an 710072 China Centre for Advanced Structural Materials Department of Mechanical and Biomedical Engineering City University of Hong Kong Kowloon Tong Kowloon Hong Kong China Université de Lyon MATEIS UMR CNRS5510 Bat. B. Pascal INSA-Lyon F-69621 Villeurbanne cedex France Key Laboratory for Structures Institute of Materials Science Shanghai University Shanghai 200444 China departament de Física EETAC Universitat Politécnica de Catalunya 08860-Castelldfels Barcelona Spain

Understanding mechanical relaxation, such as primary（α） and secondary（β） relaxation, is key to unravel the intertwined relation between the atomic dynamics and non-equilibrium thermodynamics in metallic glasses. At a fundamental level, relaxation, plastic deformation, glass transition, and crystallization of metallic glasses are intimately linked to each other, which can be related to atomic packing, inter-atomic diffusion, and cooperative atom movement. Conceptually, βrelaxation is usually associated with structural heterogeneities intrinsic to metallic glasses. However, the details of such structural heterogeneities, being masked by the meta-stable disordered long-range structure, are yet to be understood. In this paper, we briefly review the recent experimental and simulation results that were attempted to elucidate structural heterogeneities in metallic glasses within the framework of β relaxation. In particular, we will discuss the correlation amongβ relaxation, structural heterogeneity, and mechanical properties of metallic glasses.

关键词： metallic glass structural heterogeneity mechanical property secondary relaxation

dynamic mechanical relaxation behavior of Zr_(35)Hf_(17.5)Ti_(5.5)Al_(12.5)Co_(7.5)Ni_(12)Cu_(10)high entropy bulk metallic glass

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Journal of Materials Science & Technology 2021年第24期83卷 248-255页

作者： L.T.Zhang Y.J.duan T.Wada H.Kato J.M.pelletier d.Crespo E.Pineda J.C.Qiao School of Mechanics Civil Engineering and ArchitectureNorthwestern Polytechnical UniversityXi’an710072China Institute for Materials Research Tohoku UniversitySendai980-8577Japan Universitéde Lyon MATEISUMR CNRS5510Bat.B.PascalINSA-LyonF-69621Villeurbanne CedexFrance department of Physics Barcelona Research Center in Multiscale Science and TechnologyInstitute of Energy TechnologiesUniversitat Politècnica de Catalunya08019BarcelonaSpain

Non-equiatomic high entropy bulk metallic glasses were reported recently and show unique mechanical and physical *** mechanical relaxation behavior of Zr_(35)Hf_(17.5)Ti_(5.5)Al_(12.5)Co_(7.5)Ni_(12)Cu_(10)high entropy bulk metallic glass was investigated by dynamic mechanical analysis(dMA)and the mechanical spectra could be well described by the quasi-point defects(QPd)*** to typical metallic glasses,the intensity of theβrelaxation of Zr_(35)Hf_(17.5)Ti_(5.5)Al_(12.5)Co_(7.5)Ni_(12)Cu_(10)high entropy bulk metallic glass is lower due to the sluggish *** the same time,the correlation factor is higher than that of conventional metallic glasses and this is ascribed to the high configuration *** parallel,physical aging below the glass transition temperature leads to a decrease of atomic mobility,caused by a decrease of the concentration of defects.

关键词： High entropy bulk metallic glass Mechanical relaxation Quasi-point defects Physical aging

Homogeneous Plastic Flow of Fully Amorphous and Partially Crystallized Zr_(41.2)Ti_(13.8)Cu_(12.5)Ni_(10)Be_(22.5) Bulk Metallic Glass

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Journal of Materials Science & Technology 2003年第6期19卷 557-560页

作者： Q.WANG J.J.Blandin M.Suery B.Van de Moortele J.M.pelletier GPM2 ENSPG D.U. B.P.46 38042 Grenoble France Institute of Materials Shanghai University Shanghai 200072 ChinaGPM2 ENSPG D.U. B.P.46 38042 Grenoble FranceGPM2 ENSPG D.U. B.P.46 38042 Grenoble FranceGEMPPM Bat. B. PascalINSA 69621 Villeurbanne Cedex FranceGEMPPM Bat. B. PascalINSA 69621 Villeurbanne Cedex France

The homogeneous plastic flow of fully amorphous and partially crystallized Zr(41.2)Ti(13.8)Cu(12.5)Ni(10)Be(22.5) bulk metallic glass (Vitl) has been investigated by compression tests at high temperatures in supercooled liquid region. Experimental results show that at sufficiently low strain rates, the supercooled liquid of the fully amorphous alloy reveals Newtonian flow with a linear relationship between the flow stress and strain rate. As the strain rate is increased, a transition from linear Newtonian to nonlinear flow is detected, which can be explained by the transition state theory. Over the entire strain rate interval investigated, however, only nonlinear flow is present in the partially crystallized alloy, and the flow stress for each strain rate is much higher. It is found that the strain rate-stress relationship for the partially crystaltized alloy at the given temperature of 646 K also obeys the sinh law derived from the transition state theory, similar to that of the initial homogeneous amorphous alloy. Thus, it is proposed that the flow behavior of the nanocrystalline/amorphous composite at 646 K is mainly controlled by the viscous flow of the remaining supercooled liquid.

关键词： Homogeneous plastic flow Zr41.2Ti13.8Cu12.5Ni10Be22.5 amorphous alloy,Partially crystallized amorphous alloy

Irrigation's effect and applied selection on the fiber quality of Ethyl MethaneSulfonate(EMS)treated upland cotton(Gossypium hirsutum L.)

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Journal of Cotton Research 2018年第4期1卷 1-11页

作者： WITT Travis W ULLOA Mauricio pelletier Mathew G. MENdU Venugopal RITCHIE Glen L. Plant and Soil Science department Texas Tech University USdA-ARS PA CSRL Plant Stress and Germplasm Development Research USdA-ARS Cotton Production and Processing Research Laboratory

Background: Producing rainfed cotton(Gossypium hirsutum L.) with high fiber quality has been challenging in the Texas High Plains because of extended periods of insufficient rainfall during sensitive boll developmental *** variation created by Ethyl MethaneSulfonate(EMS) mutagen has successfully improved fiber quality of cotton. However, little is known about the effect of water deficit environments on fiber quality. Three EMS treated populations were advanced from the first to the fourth generation(M1 to M4) as bulk harvested populations. In2014, single-plant divergent selection was applied based on perceived morphological and agronomic differences seen during and at the end of the ***: Analyses from these selections in 2014-2016 showed significant(Pd within populations for fiber traits(micronaire, length, strength, uniformity, and elongation) when compared with the original non-treated EMS source; some selections were found to have excellent fiber quality under diverse ***: Some of these selections are being considered for germplasm release and could be useful for improving the fiber quality of cotton under water limited conditions, thereby helping to ensure the long-term survival of the cotton industry on the Texas High Plains.

关键词： Breeding drought EMS Ethyl MethaneSulfonate Fiber quality Selection

导波光学技术在测量“夹心”光学薄膜各向异性方面的应用:不同膜堆结构中同类薄膜特性的比较

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光电工程 1990年第3期17卷 29-36页

作者：胡又林 E.pelletier 武汉测绘科技大学光学仪器系 (Laboratoire d'optique des surfaces et des couches minces unité associé au CNRS(U.A.1120)13397 Marseille cedex 13 France

本文介绍了应用导波光学技术测量“夹心”光学薄膜的特征参数的方法,并研究了比较简单的结构(由二、三层膜组成),检测到了高折射率薄膜的各向异性。从不同结构的膜系中的同类薄膜的比较中发现了单层膜与膜堆中对应的“夹心”膜之间在折... 详细信息

本文介绍了应用导波光学技术测量“夹心”光学薄膜的特征参数的方法,并研究了比较简单的结构(由二、三层膜组成),检测到了高折射率薄膜的各向异性。从不同结构的膜系中的同类薄膜的比较中发现了单层膜与膜堆中对应的“夹心”膜之间在折射率和各向异性上的差别。

关键词：光学薄膜导波光学测量各向异性