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作者： Mwamba Mul.mbo theodore 浙江大学

学位级别：硕士

油菜(Brassica napus l.)是一种重要可食用油来源,并且拥有一定程度的抗金属等胁迫能力。因此发挥它在抗重金属胁迫上的潜力是很重要的。在不同的植物中研究不同的重金属元素的代谢机理,特别是对比不同的重金属特性(如镉和铜),也是很重... 详细信息

油菜(Brassica napus l.)是一种重要可食用油来源,并且拥有一定程度的抗金属等胁迫能力。因此发挥它在抗重金属胁迫上的潜力是很重要的。在不同的植物中研究不同的重金属元素的代谢机理,特别是对比不同的重金属特性(如镉和铜),也是很重要的。在这样的背景下,本试验试图通过镉和铜在甘蓝型油菜体内的富集方式、亚细胞的分布情况和化学形态来开展研究。此外,镉和铜互作的毒理学评估结果是两种重金属有可能在污染的土壤共存。鉴此,我们开展了本实验研究,取得的主要研究结果如下：(1)油菜幼苗在水培的条件下,在第五周进行不同程度的重金属处理(0、50、200μM),通过对重金属的积累情况来评价镉和铜的毒性作用。在整株植物中,镉的积累量高于铜。尽管铜的富集程度低,但造成了较高的氧化应激反应和较严重的生长抑制,叶绿素含量也下降更多。然而增加镉的浓度也可造成同样的毒害结果。同样浓度的两种金属都能影响水、矿物营养的吸收,但铜更不利于钾和锰的积累。相比浙双758,品种浙大622的生长抑制和氧化胁迫更明显,但是两个品种之间营养元素的改变程度却是相似的。结果还表明镉和铜对谷胱甘肽循环的影响不同,铜相比于逆境的含量高,而锌的活性还是镉逆境下高。通过对两种重金属共同处理下的积累和相关的毒害测定来探究铜和镉的互作效应,镉和铜相互影响其在植物体内的富集和毒害,镉和铜在油菜中的协同吸收造成了生长抑制,叶绿素损失和氧化的损伤。对敏感品种(浙大622)和抗性品种(浙双758)的比较中,我们发现存在协同作用。相比之下,重金属的协同作用对营养元素含量减少却是没有影响。然而,镉对铜的吸收的刺激效应只有在低浓度是有效的。与镉效应相反,铜对镉的吸收限制了镉的吸收。重金属的互作对矿质营养元素的影响较小。(2)在上述同样的条件下,通过重金属的亚细胞分布和化学形态探究镉和铜的特异性毒害。结果显示细胞壁和液泡中积累了最高比例的重金属。然而,与铜相比,镉在细胞壁上的残留少,部分解释了其较高的积累位置在可溶部分。尽管其较高的交换量,但是铜也显著地积累在可溶性部分,说明油菜植物细胞壁电荷密度低。尽管如此,抗性品种浙双758比敏感的浙大622在细胞壁上积累了更多的镉和铜;在可溶性部分的重金属浓度上没有基因型的差别存在。镉和铜在敏感的细胞器有不同的表现：镉在叶绿体和线粒体分布均匀,铜优先积累在叶绿体上,相应的在铜处理过的植物的叶绿体明显变化大。至于重金属的化学形态,镉和铜各自与不同细胞配体相互作用,说明存在不同的解毒途径;磷酸盐配体积极络合铜,但镉会以有机配体为主,使它们成为第二选择的配体。添加铜是由有机配体和草酸盐固定化,但后者不能够缓解镉的毒害。在重金属的毒性部分,镉的比例很大,以水萃取的形式存在,而铜更多以乙醇提取的形式存在。

关键词：甘蓝型油菜镉铜互作效应重金属特性毒性积累胞内酶活

基于AFM的纳米尺度线宽计量模型及其算法的研究

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机械工程学报 2004年第4期40卷 50-57页

作者：赵学增褚巍 theodore V Vorburger Joseph Fu John Song Cattien V Nguyen 哈尔滨工业大学机电工程学院哈尔滨150001 美国国家标准与技术研究院美国国家航空与航天管理局

纳米尺度线宽的测量广泛应用于半导体制造、数据存储、微机电系统等领域。随着制造技术的进步,线宽的极限尺寸也变得越来越小,目前已经缩小至100 nm左右。在这一尺度范围内,由于样本制造技术的限制和测量仪器的影响,目前很难得到准确的... 详细信息

纳米尺度线宽的测量广泛应用于半导体制造、数据存储、微机电系统等领域。随着制造技术的进步,线宽的极限尺寸也变得越来越小,目前已经缩小至100 nm左右。在这一尺度范围内,由于样本制造技术的限制和测量仪器的影响,目前很难得到准确的测量结果。为了获得样本的真实几何尺寸信息,剔除测量方法和仪器本身对测量结果的影响,建立了一个基于AFM测量技术的线宽计量模型和相应算法。该模型将被测样本的截面轮廓用20个关键点分成5个部分共19段,用基于最小二乘的直线来拟合实际轮廓。应用该模型和算法可以分别得到单刻线轮廓拟合前后的顶部线宽b_T、b_(TF),中部线宽b_M、b_(MF),底部线宽b_B、b_(BF),左右边墙角A_l.A_R,以及高度h_。使用NanoScope Ⅲa型AFM对一个单晶硅(Si)线宽样本进行了测量,测量结果表明该模型和算法可以满足纳米尺度线宽计量的基本要求。

关键词：纳米计量线宽计量模型算法原子力显微镜半导体数据存储微机电系统

不同CO_2浓度与温度条件下马铃薯叶片的淀粉浓度与比叶重和矿质元素浓度的关系(英文)

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Acta Botanica Sinica 1997年第12期39卷 1118-1125页

作者：曹卫星 theodore W.Tibbitts 南京农业大学农业部作物生长调控重点开放实验室南京210095 美国威斯康星大学园艺系威斯康星53706

三个马铃薯(Sol.num tuberosum l.)品种在500、1000、1500、2000μmol.mol.(-1)CO_2浓度与16、20℃空气温度下生长35d,测定了植株叶片的比叶重(g·m^(-2))、淀粉浓度及主要养分N、P、K、Ca、Mg的浓度。在16℃和20℃下,叶片淀粉浓度随C... 详细信息

三个马铃薯(Sol.num tuberosum l.)品种在500、1000、1500、2000μmol.mol.(-1)CO_2浓度与16、20℃空气温度下生长35d,测定了植株叶片的比叶重(g·m^(-2))、淀粉浓度及主要养分N、P、K、Ca、Mg的浓度。在16℃和20℃下,叶片淀粉浓度随CO_2浓度的增加而增加,且16℃下的测定值高于20℃下的测定值。比叶重与以叶面积或干重为基础的叶片淀粉浓度成正相关。叶片N、P、Ca、Mg浓度与14％范围内的淀粉浓度成负相关,但与高于14％的淀粉浓度无明显关系。去除淀粉效应后的比叶重及叶片养分浓度呈现类似的变化趋势。然而,不同CO_2浓度下的叶片K浓度相对稳定,因此受淀粉浓度影响较小。研究结果表明,不同CO_2浓度与温度条件下马铃薯叶片的比叶重及N、P、Ca、Mg浓度的变化不完全是叶片淀粉浓度的变化所致。

关键词： CO2浓度温度比叶重淀粉马铃薯矿质元素

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乙硼烷的工业生产

无机盐工业 1960年第6期 29-34页

作者： CARl.l. S. HEBBICK NORMAN KIRK theodore l. ETHERINGTON A. EUGENE SCHUBERT 寗望珵赵新正

譯序硼烷在化学史上虽然已經有了四十多年的历史,可是作为高能燃料大量生产,还是最近一、两年之內的事。硼烷的实驗室制备和大規模的工业生产,是現代化学与化学工业的尖端技术之一。虽然远在19世紀末和20世紀初就有化学

关键词：乙硼烷乙醚捐失氢化硼烷类硼氢化物硼烷工业生产

Identification of heat-induced proteomes in meiotic pol.en mother cel.s of tomato'Maxifort'using singl.-cel.-type tandem mass tag(TMT)proteomics

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Vegetabl. Research 2022年第1期2卷 9-22页

作者： Hui l. Yaoguo Qin Xingbo Wu Joshua O'Hair Jesse Potts Suping Zhou Yong Yang Tara Fish theodore W.Thannhauser Department of Agricul.ural.and Environmental.Sciences College of AgricultureTennessee State University3500 John A.Merritt BlvdNashvilleTN 37209USA Pl.nt Soil and Nutrition Research UnitUSDA-ARSTower RoadIthacaNY 14853USA

Heat stress(HS)poses a significant chal.enge to tomato production due to disruption of the reproductive organs,especial.y the mal. *** study reports HS-induced proteome changes in meiotic pol.en mother cel.s during earl. stages of anther ***(Sol.num l.copersicum l.×***)'Maxifort'were grown in a heated pol.tunnel.in Nashvil.e,Tennessee,*** at fl.wering stage were subjected to heat treatment at 40±2℃ for 4 hr(11:00−15:00 HR);and the non-heat-treated control.was at 30±2℃(day/night)at the same period of time for 10 *** size of the fl.wer buds containing meiotic pol.en mother cel.s was determined based on the histol.gy of DAPI stained cross section of *** buds were embedded in optimal.cutting temperature sol.tions(OCT)and then cut into sections of 20μm *** containing meiotic pol.en mother cel.s were col.ected using l.ser capture microdissection(l.M).A protein extraction procedure was optimized for the l.M col.ected pol.en sampl.s which yiel.ed 25−30μg protein from 150,000−200,000 pol.en *** heatinduced proteomes of meiotic pol.en mother cel.s were quantified using tandem mass tag(TMT)quantitative proteomics *** the 6,343 quantified proteins,254 differential.y expressed proteins(DEPs)showed significant differences in abundance l.vel.from heat treated to non-heat-treated control.*** heat-up-regul.ted-DEPs(96 proteins)incl.de heat shock proteins,cal.eticul.n and exocytosis(synaptobrevin)which are invol.ed in protein fol.ing/refol.ing/targeting/removal.and secretion of aggregated and damaged proteins/*** heat-down-regul.ted-DEPs(158 proteins)were invol.ed in pathways of ubiquitin-mediated protein degradation,antioxidant mechanism,and metabol.c processes of carbohydrates and *** affecting apoptotic programmed cel. death and pol.en mother cel. meiotic activity were significantl. changed under *** identified proteins and the affected biol.gical.processe

关键词： mother Max fol.ing

Pedicl. screw accuracy assessment in Excel.iusGPS?robotic spine surgery:eval.ation of deviation from pre-pl.nned trajectory

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Chinese Neurosurgical.Journal 2018年第3期4卷 118-123页

作者： Bowen Jiang A.Karim Ahmed Corinna C.Zygourakis Samuel.Kal. Al.x M.Zhu Jakub Godzik Camil. A.Mol.na Ari M.Bl.tz Al. Bydon Neil.Crawford Nichol.s theodore Department of Neurosurgery The Johns Hopkins School of MedicineThe Johns Hopkins Hospital600 N.Wolfe StreetMeyer 7-113BaltimoreMD 21287USA Department of Neurosurgery Barrow Neurological InstituteSt.Joseph’s Hospital and Medical CenterPhoenixAZUSA Department of Neuroradiol.gy Johns Hopkins School of MedicineThe Johns Hopkins Hospital600 N Wolfe StBaltimoreMD 21287USA Department of Neurosurgery Johns Hopkins University School of Medicine1800 Orleans StreetZayed Tower Mailstop 6007Baltimore 21287MDUSA Gl.bus Medical.Inc 2560 General Armistead AveAudubon 19403PAUSA

Background: The Excel.iusGPS?(Gl.bus Medical. Inc., Audubon, PA) is a next-generation spine surgery robotic system recentl. approved for use in the United States. The objective of the current study is to assess pedicl. screw accuracy and cl.nical.outcomes among two of the first operative cases util.zing the Excel.iusGPS?robotic system and describe a novel.metric to quantify screw deviation. Methods: Two patients who underwent l.mbar fusion at a singl. institution with the Excel.iusGPS?surgical.robot were incl.ded. Pre-operative trajectory pl.nning was performed from an intra-operative CT scan using the O-arm (Medtronic, Inc., Minneapol.s, MN). After robotic-assisted screw impl.ntation, a post-operative CT scan was obtained to confirm ideal.screw pl.cement and accuracy with the pl.nned trajectory. A novel.pedicl. screw accuracy al.orithm was devised to measure screw tip/tail.deviation distance and angul.r offset on axial.and sagittal.pl.nes. Screw accuracy was concurrentl. determined by a bl.nded neuroradiol.gist using the traditional.Gertzbein-Robbins method. Cl.nical.variabl.s such as symptomatol.gy, operative data, and post-operative fol.ow-up were al.o col.ected. Resul.s: Eight pedicl. screws were pl.ced in two l.-l. fusion cases. Mean screw tip deviation was 2.1 mm (range 0.8-5.2 mm), mean tail.deviation was 3.2 mm (range 0.9-5.4 mm), and mean angul.r offset was 2.4 degrees (range 0.7-3.8 degrees). Al. eight screws were accuratel. pl.ced based on the Gertzbein-Robbins scal. (88% Grade A and 12% Grade B). There were no cases of screw revision or new post-operative deficit. Both patients experienced improvement in Frankel.grade and Karnofsky Performance Status (KPS) score by 6 weeks post-op. Concl.sion: The Excel.iusGPS? robot al.ows for precise execution of an intended pre-pl.nned trajectory and accurate screw pl.cement in the first patients to undergo robotic-assisted fusion with this technol.gy.

关键词： Robotic spine surgery Robot-assisted surgery Excel.ius GPS® Gertzbein-Robbins Pedicl. screw accuracy

高热生物学与肿瘤治疗：对“l.nce Armstrong效果”的假设

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美国医学会杂志（中文版） 2007年第6期26卷 368-371页

作者： Donal. S. Coffey Robea H. Getzenberg theodore l.DeWeese 彭楠（译）蒋彦勇（译） Departments of Urol.gy Johns Hopkins University School.of Medicine Baltimore Md. Radiation Oncol.gy and Mol.cul.r Radiation Sciences Sidney Kinunel.Comprehensive Cancer Center 不详

在肿瘤研究中，可能没有比懂得大多数睾丸癌患者能被非常有效地治疗的分子机理更为重要的了。例如，l.nce Armstrong被诊断为晚期睾丸癌并发生转移，但是其治疗非常成功，以致随后他能赢得多项极限环法旅行比赛。尽管对此类晚期睾丸癌... 详细信息

在肿瘤研究中，可能没有比懂得大多数睾丸癌患者能被非常有效地治疗的分子机理更为重要的了。例如，l.nce Armstrong被诊断为晚期睾丸癌并发生转移，但是其治疗非常成功，以致随后他能赢得多项极限环法旅行比赛。尽管对此类晚期睾丸癌治疗成功目前已属平常，但是大多数其他类型晚期实体肿瘤仍无法达到这样的效果。如何解释睾丸癌治疗令人惊奇的疗效，能否于细胞和分子水平对其结果做出解释？了解l.nce Armstrong疗效的基础可以为其他采用现行最佳系统治疗难以控制的晚期实体肿瘤的治愈提供治疗目标。

关键词：肿瘤治疗热生物学晚期实体肿瘤睾丸癌分子机理分子水平系统治疗癌患者

Effects of music and video on perceived exertion during high-intensity exercise

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Journal.of Sport and Heal.h Science 2017年第1期6卷 81-88页

作者： Enoch C.Chow Jennifer l.Etnier Department of Kinesiol.gy University of North Carolina at GreensboroGreensboroNC 27412USA

Background: Dissociative attentional.stimul.(e.g., music, video) are effective in decreasing ratings of perceived exertion(RPE) during l.w-tomoderate intensity exercise, but have inconsistent resul.s during exercise at higher intensity. The purpose of this study was to assess attentional.focus and RPE during high-intensity exercise as a function of being exposed to music, video, both(music and video), or a no-treatment control.***: During the first session, heal.hy men(n = 15) compl.ted a maximal.fitness test to determine the workl.ad necessary for high-intensity exercise(operational.zed as 125% ventil.tory threshol.) to be performed during subsequent sessions. On 4 subsequent days, they compl.ted 20 min of high-intensity exercise in a no-treatment control.condition or whil. l.stening to music, watching a video, or both. Attentional.focus, RPE,heart rate, and distance covered were measured every 4 min during the ***: Music and video in combination resul.ed in significantl. l.wer RPE across time(partial.η~2= 0.36) and the size of the effect increased over time(partial.η~2= 0.14). Additional.y, music and video in combination resul.ed in a significantl. more dissociative focus than the other conditions(partial.η~2= 0.29).Concl.sion: Music and video in combination may resul. in l.wer perceived exertion during high-intensity exercise when compared to music or video in isol.tion. Future research wil. be necessary to test if reductions in perceived exertion in response to dissociative attentional.stimul. have impl.cations for exercise adherence.

关键词： Acute exercise Attentional.focus Effort Perceived exertion

Synergistic effects of chromium and copper on photosynthetic inhibition,subcel.ul.r distribution,and rel.ted gene expression in two Brassica napus cul.ivars

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Synergistic effects of chromium and copper on photosynthetic...