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chemical composition of Root and Stem Saps in Relation to cadmium Resistance and Accumulation in Brassica parachinensis

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Pedosphere 2007年第3期17卷 352-359页

作者： WU Qi-Tang XU zhao-Li YE Hui j. W. c. WONG college of Natural Resources and Environment South China Agricultural University Guangzhou 510642 （China） Department of Biology Hong Kong Baptist University Kowloon Tong Hong Kong SAR （China）

Sap mixtures of the xylem, phloem, and vacuoles from low and high cd accumulator varieties of Brassica parachinensis L. H. Bailey were analyzed under cd stress to understand the biochemical mechanisms of cd accumulation in plants. Low cd accumulator ('Teqing-60') and high cd accumulator ('chixin-2') plants were grown in cd-treated soil in pots in a greenhouse. Percentage of cell wall-bound cd was estimated. pH level and the concentrations of amino acids, organic acids, anions, and cations in both stem and root saps were determined for the calculation of cd speciations using the computer program GEOcHEM. The results showed that 'Teqing-60' had a significantly higher (P≤0.05) percentage of cd bound to cell walls in roots and a significantly higher (P≤0.05) pH in the root sap. 'Teqing-60' also contained a higher concentration of total amino acids in both roots and stems compared with the high cd accumulator variety 'chixin-2'. However, between the two accumulators, for stems and for roots, there were no significant differences in non-amino organic acids. GEOcHEM calculations showed that cd in the root sap of 'Teqing-60' mainly combined with amino acids, especially alanine. compared with 'chixin-2', in the root sap of 'Teqing-60', much lower levels of cd as free ions or bound to simple ligands were found, indicating that less 'Teqing-60' is transferred to stems and leaves. cadmium activity in the shoot sap of 'Teqing-60' was much lower than that in 'chixin-2'; therefore, 'Teqing-60' exhibited higher cd resistance. However, direct determination of the cd complexes from xylem and phloem sap is needed to verify these results.

关键词： Brassica parachinensis cadmium plant sap resistance speciation

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Electro-osmotic flow and heat transfer of a non-Newtonian fluid in a hydrophobic microchannel with Navier slip

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journal of Hydrodynamics 2015年第5期27卷 647-657页

作者： MISRA j.c. SINHA A. Adjunct Professor Centre for Healthcare Science and Technology Indian Institute of Engineering Science and Technology School of Medical Science and Technology Indian Institute of Technology

In this paper, we investigate the implications of electro-osmosis on electrohydrodynamic transport of a non-Newtonian fluid on a hydrophobic micro-channel by developing a suitable analytical method. Velocity-slip and temperature-jump conditions are paid due attention. An attempt has been made to examine the effects of rheological and electro-osmotic parameters on the kinematics of the fluid. The nonlinear Poisson-Boltzmann equation governing the formation of the electrical double layer and the body force that is generated by the applied potential are accounted for in the study. Perturbation solutions are presented. In order to exhibit the applicability of the analysis, the problem of electro-osmotic flow and heat transfer of blood in an arteriole has been taken up as an illustrative example of a real-life problem. An intensive quantitative study has been made through numerical computation of the physical variables involved in the analysis, which are of special interest in the study. The computational results are presented graphically. The study reveals that the temperature of blood can be controlled by increasing/decreasing the joule heating parameter.

关键词： electro-osmotic flow hydrophobic microchannel electrical double layer viscoelastic fluid velocity-slip temperature-jump

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Assessment of cOVID-19 aerosol transmission in a university campus food environment using a numerical method

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Geoscience Frontiers 2022年第6期13卷 265-278页

作者： M.zhao c.Zhou T.chan c.Tu Y.Liu M.Yu Laboratory of Aerosol Science and Technology China Jiliang UniversityHangzhouChina Department of Mechanical Engineering The Hong Kong Polytechnic UniversityKowloonHong KongChina college of Modern Science China Jiliang UniversityHangzhouChina

With the prevalence of cOVID-19,the phenomenon of viruses spreading through aerosols has become a focus of *** in university dining halls have a high risk of exposure to respiratory droplets from others without the protection of face masks,which greatly increases the risk of cOVID-19 ***,the transmission mechanism of respiratory droplets in extremely crowded dining environments should be *** this study,a numerical simulation of coughing at dining tables under two conditions was performed,namely the presence and absence of protective partitions,and the evaporation and condensation of aerosol droplets in the air were *** using the numerical method,we analyzed and verified the isolation effect of dining table partitions in the propagation of aerosol *** effect of changes in room temperature on the diffusion of coughed aerosols when partitions were present was *** demonstrated how respiratory droplets spread through coughing and how these droplets affect ***,we proposed a design for a dining table partition that minimizes the transmission of cOVID-19.

关键词： cOVID-19 transmission University dining hall cough Table partition computational fluid dynamics

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Grain refinement in low SFE and particle-containing nickel aluminium bronze during severe plastic deformation at elevated temperatures

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journal of Materials Science & Technology 2021年第23期82卷 57-68页

作者： c.j.Barr K.Xia Department of Mechanical Engineering University of MelbourneVictoria3010Australia DMTc Ltd. 24 Wakefield St.HawthornVIC3122Australia

The influence of particle size and morphology on grain refinement in low stacking fault energy(SFE)alloys was studied by comparing the grain structures in single-and multi-phase Al-bronze(AB)alloys following equal channel angular pressing(EcAP)between 350 and 500℃.In particular,nickel aluminium bronze(NAB)was chosen as it contained both coarse and fine rounded particles,as well as a lamellar phase which evolved during *** refinement in the single-phase alloy was achieved through dynamic recrystallisation initiated at deformed twin *** contrast,different mechanisms were observed in the particle-containing *** around the coarseκⅡparticles(~5μm)was promoted through particle stimulated nucleation(PSN),whereas recrystallisation in the region of the fineκⅣ(~0.4μm)was delayed due to the activation of secondary *** refinement in areas of the lamellarκⅢshowed significant variation,depending on the lamellar orientation relative to the shear plane of *** the lamellae deformed,numerous high angle grain boundaries were generated between fragments and served as nucleation sites for recrystallisation,while PSN occurred around spheroidised *** spreading of theκⅢparticles by EcAP then enhanced the total area of recrystallised grains.

关键词： Equal channel angular pressing copper alloys Grain refinement Stacking fault energy Severe plastic deformation

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纤维蛋白原及血管内皮功能指标与下肢动脉硬化闭塞症患者血管腔内介入治疗后发生血管再狭窄的关系研究

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实用心脑肺血管病杂志 2025年第1期33卷 75-80页

作者：赵峰邓默河北大学附属医院介入血管外科河北省保定市071000 河北大学附属医院麻醉科河北省保定市071000

目的探讨纤维蛋白原(FIB)及血管内皮功能指标与下肢动脉硬化闭塞症(LEASO)患者血管腔内介入治疗后发生血管再狭窄的关系。方法回顾性选取2021年5月—2022年9月河北大学附属医院收治的116例LEASO患者为研究对象,收集患者的临床资料,根据... 详细信息

目的探讨纤维蛋白原(FIB)及血管内皮功能指标与下肢动脉硬化闭塞症(LEASO)患者血管腔内介入治疗后发生血管再狭窄的关系。方法回顾性选取2021年5月—2022年9月河北大学附属医院收治的116例LEASO患者为研究对象,收集患者的临床资料,根据患者是否发生血管再狭窄将其分为再狭窄组(n=51)和非再狭窄组(n=65)。采用多因素Logistic回归分析探讨LEASO患者血管腔内介入治疗后发生血管再狭窄的影响因素;采用限制性立方样条回归分析探讨FIB、内皮素1(ET-1)、一氧化氮(NO)与LEASO患者血管腔内介入治疗后发生血管再狭窄风险的剂量-反应关系。结果再狭窄组肿瘤坏死因子α(TNF-α)、c反应蛋白(cRP)、c反应蛋白/白蛋白比值(cAR)、FIB、ET-1高于非再狭窄组,白蛋白、NO低于非再狭窄组(Pc回归分析结果显示,TNF-α、cRP、白蛋白、cAR、FIB、ET-1、NO是LEASO患者血管腔内介入治疗后发生血管再狭窄的独立影响因素(P<0.05)。限制性立方样条回归分析结果显示,FIB、ET-1、NO与LEASO患者血管腔内介入治疗后发生血管再狭窄风险均具有非线性剂量反应关系(P=0.614,P_(非线性)=0.012;P=0.285,P_(非线性)=0.003;P=0.417,P_(非线性)=0.005),随着FIB、ET-1的升高、NO的降低,LEASO患者血管腔内介入治疗后发生血管再狭窄风险呈非比例的增加。结论FIB、ET-1升高是LEASO患者血管腔内介入治疗后发生血管再狭窄的危险因素,NO升高是LEASO患者血管腔内介入治疗后发生血管再狭窄的保护因素;FIB、ET-1、NO与LEASO患者血管腔内介入治疗后发生血管再狭窄风险均具有非线性剂量反应关系。

关键词：闭塞性动脉硬化下肢动脉硬化闭塞症血管内操作纤维蛋白原内皮素1 一氧化氮血管再狭窄

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Amorphous WO_(3-x)thin films with color characteristics tuned by the oxygen vacancies created during reactive Dc sputtering

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journal of Materials Science & Technology 2021年第19期78卷 223-228页

作者： c.Guillén j.Herrero Departamento de Energia(cIEMAT) Avda.Complutense 40.28040 MadridSpain

Tungsten oxides are interesting for a variety of applications due to their versatile optoelectronic characteristics,which can be tuned changing the composition and/or the crystalline *** due to sub-bandgap absorption is often achieved by ion intercalation or doping in WO_(3):M films(with M=H^(+),Li^(+),Na^(+),*** extra electrons),but a more direct way is creating charged oxygen vacancies(V_O^(+)and/or V_O~(2+))in sub-stoichiometric WO_(3-x)***,amorphous WO_(3-x)thin films are obtained by reactive Dc sputtering of a pure W target,on unheated glass substrates,changing the oxygen to argon pressures *** control of intrinsic defects(oxygen vacancies and tungsten valence states)by the oxygen partial pressure allows tuning the morphology,sub-bandgap absorption and carrier density in these WO_(3-x)films,as it is proven by Raman spectroscopy,atomic force microscopy,optical spectrophotometry and Hall effect measurements.

关键词： Metal oxide Stoichiometry Optical absorption Electrical conductivity

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On the microstructural origin of premature failure of creep strength enhanced martensitic steels

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journal of Materials Science & Technology 2021年第28期87卷 269-279页

作者： j.Li c.Xu G.Zheng W.j.Dai c.c.Bu G.chen MIIT Key Laboratory of Advanced Metallic and Intermetallic Materials Technology Engineering Research Center of Materials Behavior and DesignMinistry of EducationNanjing University of Science and TechnologyNanjing210094China Nanjing jiuzhu New Materials Institute co. Ltd.Nanjing211151China condensed Materials Laboratory co. Ltd.Yangzhou225200China Yangzhou chengde Steel Pipe co. Ltd.Yangzhou225200China

The creep strength enhanced martensitic steels are key material for the main power generating units in ultra-supercritical *** on the evaluation of their creep rupture life show there is an overestimation of rupture life after long-term creep,which is known as premature ***,the microstructural origin of the premature failure remains *** in this study,we have carefully investigated the microstructural transformations and their influences on creep rupture behavior,showing that the evolution of martensite and M_(23)c_(6) carbides as well as Laves phase are responsible for the premature *** using multi-step TTP-LMP method,we confirmed a three-stage creep rupture behavior under different stress *** quantitative analysis showed that the coarsening of M_(23)c_(6) carbides and recovery of martensite exert equal and dominant effects on the premature failure in the medium stress region,while precipitation and coarsening of Laves phase are responsible for the premature failure in the low stress region.

关键词： creep strength enhanced martensitic steel Premature failure M_(23)c_(6)carbides Martensite recovery Laves phase

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Oryzalexin S biosynthesis:a cross-stitched disappearing pathway

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aBIOTEcH 2023年第1期4卷 1-7页

作者： Le zhao Richard Oyagbenro Yiling Feng Meimei Xu Reuben j.Peters Roy j.carver Department of Biochemistry Biophysics and Molecular BiologyIowa State UniversityAmesIA50011USA

Rice produces many diterpenoid phytoalexins and,reflecting the importance of these natural products in this important cereal crop plant,its genome contains three biosynthetic gene clusters(BGcs)for such *** chromosome 4 BGc(c4BGc)is largely associated with momilactone production,in part due to the presence of the initiating syn-copalyl diphosphate(cPP)synthase gene(OscPS4).Oryzalexin S is also derived from ***,the relevant subsequently acting syn-stemarene synthase gene(OsKSL8)is not located in the *** of oryzalexin S further requires hydroxylation at carbons 2 and 19(c2 and c19),presumably catalyzed by cytochrome P450(cYP)*** it is reported the closely related cYP99A2 and cYP99A3,whose genes are also found in the c4BGc catalyze the necessary c19-hydroxylation,while the closely related cYP71Z21 and cYP71Z22,whose genes are found in the recently reported chromosome 7 BGc(c7BGc),catalyze subsequent hydroxylation at c2α.Thus,oryzalexin S biosynthesis utilizes two distinct BGcs,in a pathway cross-stitched together by ***,in contrast to the widely conserved c4BGc,the c7BGc is subspecies(ssp.)specific,being prevalent in *** and only rarely found in the other major ***,while the closely related syn-stemodene synthase OsKSL11 was originally considered to be distinct from OsKSL8,it has now been reported to be a *** derived allele at the same genetic ***,more detailed analysis indicates that OsKSL8(j)is being replaced by OsKSL11(OsKSL8i),suggesting introgression from *** to(sub)tropical japonica,with concurrent disappearance of oryzalexin S production.

关键词： Biosynthetic gene clusters Phytoalexins Diterpenoids Rice evolution

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Value of multi-quadrants biopsy:Pooled analysis of 11 population-based cervical cancer screening studies

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chinese journal of cancer Research 2020年第3期32卷 383-394页

作者： Yuqian zhao Fanghui zhao Shangying Hu Xun Zhang Wenhua Zhang Qinjing Pan julia c Gage Rengaswamy Sankaranarayanan Youlin Qiao Department of cancer Epidemiology National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China Research center of cancer Prevention Sichuan Cancer Hospital&InstituteSichuan Cancer CenterSchool of MedicineUniversity of Electronic Science and Technology of ChinaChengdu 610041China Department of Pathology National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China Department of Gynaecology National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China Division of cancer Epidemiology and Genetics National Cancer InstituteRockville 20852USA Research Triangle Institute Global India New Delhi 110019India Screening Group Section of Early Detection and PreventionInternational Agency for Research on CancerLyon 69372France

Objective:The accuracy of colposcopy-guided biopsy is key to the success of colposcopic triage in cervical cancer screening ***,there is no widely adopted biopsy guideline up to *** study aimed to determine whether multi-quadrants biopsy improves the yield of cervical ***:Eleven population-based cervical cancer screening studies were conducted in ***,highrisk human papillomavirus(hrHPV)testing and visual inspection were performed for primary *** positive on one or more tests were referred for colposcopy and *** proportion of detected cervical intraepithelial neoplasia(cIN)2+and yields by quadrant lesion-targeted biopsy or 4-quadrant random biopsy were ***:Among 4,923 females included,1,606 had quadrant lesion-targeted biopsy,and 3,317 had 4-quadrant random *** cumulative cIN2+yield increased from 0.10 for only one quadrant-targeted biopsy to 0.21,0.34,and 0.58 for at most two,three and four quadrants targeted *** hrHPV positive females with high-grade squamous intraepithelial lesion(HSIL)+cytology,the cumulative cIN2+yield of a second targeted biopsy in another quadrant was significantly increased(PcIN2+yield for HSIL+,low-grade squamous intraepithelial lesion(LSIL)cytology,or abnormal visual inspection via acetic acid and Lugol’s iodine(VIA/VILI)were 0.46,0.11,***:A 4-quadrant random biopsy is recommended only for hrHPV positive females with HSIL cytology,and is acceptable if hrHPV positive with LSIL cytology or with abnormal VIA/*** findings add evidences for an objective and practical biopsy standard to guide colposcopy in cervical cancer screening programs in low-and middle-income countries.

关键词： cervical cancer and precancerous lesion colposcopy low-and middle-income countries multi-quadrant biopsy screening

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Bonding quality of Yb:Y_3Al_5O_(12)/Y_3Al_5O_(12) composite crystals

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Science china(Technological Sciences) 2008年第9期51卷 1457-1463页

作者： Bourdet GILBET j c cHANTELOUP Ecole Polytechnique Laboratoire pour l'Utilisation des Lasers IntensesRoute de Saclay Palaiseau 91128 France

The Yb:Y3Al5O12/Y3Al5O12 (Yb:YAG/YAG) composite crystals were prepared by thermal bonding method with different technological parameters. The bonding in-terface of the composite crystals were observed by optical microscope, scanning electron microscope, and atom force microscope. The light scattering experiments for bonding interface of the composite crystals were measured by the laser and transmission spectra. All experiments show that high-quality Yb:YAG/YAG com-posite crystals without space transition layer and light scattering on the bonding interface can be obtained by thermal bonding method under appropriate technological parameters.

关键词： Yb:YAG/YAG bonding quality light scattering transmission spectra

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