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Exogenous cytokinin application to Actinidia chinensis var. deliciosa ‘Hayward’ fruit promotes fruit expansion through water uptake

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Horticulture Research 2017年第1期4卷 131-141页

作者： Simona Nardozza Helen L Boldingh Mark W Wohlers Andrew P Gleave Zhiwei Luo Guglielmo Costa Elspeth A MacRae Michael j.Clearwater Annette C richardson The New Zealand Institute for Plant&Food Research Limited(PFR) Mt Albert Research CentrePrivate Bag 92169AucklandNew Zealand PFR Ruakura Research CentrePrivate Bag 3123HamiltonNew Zealand Dipartimento di Scienzie Agrarie Universitàdi BolognaVia Fanin 46Bologna40127Italy PFR Te Puke Research CentreTe Puke3182New Zealand PFR Kerikeri Research CentrePrivate Bag 23KerikeriNew Zealand Scion Te Papa Tipu Innovation ParkPrivate Bag 3020RotoruaNew Zealand University of Waikato School of SciencePrivate Bag 3105HamiltonNew Zealand

Exogenous application of a cytokinin-like compound forchlorfenuron(CPPU)can promote fruit growth,although often at the expense of dry matter(DM),an important indicator of fruit *** chinensis ***‘Hayward’fruit are very responsive to CPPU treatments,but the mechanism underlying the significant fruit weight increase and associated decrease in DM is *** this study,we hypothesised that CPPU-enhanced growth increases fruit carbohydrate demand,but limited carbohydrate supply resulted in decreased fruit *** fruit development,CPPU effects on physical parameters,metabolites,osmotic pressure and transcriptional changes were assessed under conditions of both standard and a high carbohydrate *** showed that CPPU increased fruit fresh weight but the dramatic DM decrease was not carbohydrate *** glucose and fructose concentrations contributed to an increase in soluble carbohydrate osmotic pressure,which was correlated with increased water accumulation in CPPU-treated fruit and up-regulation of water channel aquaporin gene PIP2.4 at 49 days after *** analysis suggested that the molecular mechanism contributing to increased glucose and fructose concentrations was altered by carbohydrate *** standard carbohydrate supply,the early glucose increase in CPPU fruit was associated with reduced starch synthesis and increased starch *** carbohydrate supply was high,the early glucose increase in CPPU fruit was associated with a general decrease in starch synthesis but up-regulation of vacuolar invertase and fructokinase *** conclude that CPPU affected fruit expansion by increasing the osmotically-driven water uptake and its effect was not carbohydrate supply-limited.

关键词： CPPU Actinidia expansion

Relationship between Fracture Toughness and Fracture Surface Fractal Dimension in AISI 4340 Steel

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Materials Sciences and Applications 2013年第4期4卷 258-267页

作者： Luis R. Carney j.hn j. Mecholsky NAVAIR j.cksonville Jacksonville USA Materials Science & Engineering Department University of Florida Gainesville USA

This study analyzes the relationship between fracture toughness and the fracture surface fractal dimension for a set of twenty-four CT-type AISI 4340 steel specimens heat treated to a variety of tensile strengths. Specimens were tested in accordance with ASTM E 399. Their respective fracture surfaces were plated, polished, photographed under an SEM in BSE mode and measured according to the richardson method to obtain fractal dimensions. For brittle materials the limited results are consistent with previous literature: increasing fractal dimension with increasing toughness. For partially or fully ductile materials the results indicate a decrease in fractal dimension with an increase in fracture toughness. The data are modeled using a variation of the function applied to ceramics. Fracture in a ductile mode is characterized by the formation of dimples which exhibit fractal characteristics. The results are discussed in terms of the micromechanisms of fracture.

关键词： Fractal Fracture Ductile Failure Brittle Failure Mechanical Behavior

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比较儿童自发性气胸急诊手术和延期手术

世界核心医学期刊文摘（儿科学分册） 2005年第6期1卷 49-50页

作者： Qureshi F. G. Sandulache V. C. richardson W. D. j. Hackam 李丹 Division of Pediatric Surgery Children’s Hosp. Pittsburgh Sch. M. University of Pittsburgh Pittsburgh PA 15213 United States

Controversy exists regarding the timing of surgery for spontaneous pneumothorax (SP), which can be performed either after the first development of pneumothorax or after a recurrent spontaneous pneumothorax has occurred. Treatment after recurrence is often adopted because of the purported low recurrence of SP treated nonoperatively and the historical morbidity of open surgery. However, the effectiveness of VATS (to videoassisted bullectomy and pleurodesis) has raised the possibility of performing primary VATS (PV) in all patients. The authors therefore hypothesized that PV is safe and effective for SP and sought to perform a cost-benefit analysis of PV vs secondary VATS (SV). After institutional review board approval, consecu tive patients with SP (1991-2003) and no comorbidities were retrospectively divided into PV vs SV. Demographics, recurrent pneumothorax after VATS, length of stay, and costs were compared by Student’s t test/χ2. The predicted incremental cost of PV was (cost of PV) -{[cost of nonoperative treatment ×(1 -recurrence rate)] +cost of SV ×recurrence rate}. Data are means ±SEM. There were 54 spontaneous pneumothoraces in 43 patients (11 bilateral), of whom 3 were excluded because of open thoracotomy. Of 51 pneumothoraces, nonoperative treatment was attempted in 37, of whom 20 recurred and thus required SV. Primary VATS was performed in 14. Both groups had similar age, sex, weight, height, admission heart rate, and room air oxygen saturation. Total treatment length of stay was significantly shorter for PV vs SV (7.1 ±0.96 vs 10.5 ±1.2, P =.04). However, morbidity from recurrent pneumothorax after VATS occurredmore frequently after PV than SV (4/14 vs 0/20 P j.stify this approach. Contrary to the hypothesis, the increased morbidity and cost do not j.stify a strategy

关键词：急诊手术自发性气胸肺大泡切除术复发率胸膜固定术开胸术成本效益分析氧饱和度人口统计学于非

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板块构造启动的时间和机制:理论和经验探索

科学通报 2007年第5期52卷 489-501页

作者： R. j. Stern 唐俊(翻译) 牛耀龄(校对) Gcoscicnces Department University of Texas at Dallas Box 830688 Richardson TX 75083-0688 USA. 不详

板块构造是指位于对流地幔圈层之上的岩石圈的水平运动,主要由岩石圈在俯冲带的下沉作用所致.板块构造是一个典型的、非平衡复杂体系的自组系统(selforganizing,far from equilibrium complex system,SOFFECS),其驱动力主要来自热边界层... 详细信息

板块构造是指位于对流地幔圈层之上的岩石圈的水平运动,主要由岩石圈在俯冲带的下沉作用所致.板块构造是一个典型的、非平衡复杂体系的自组系统(selforganizing,far from equilibrium complex system,SOFFECS),其驱动力主要来自热边界层(岩石圈)的反向浮力,同时又受控于变形岩石圈与下覆粘性软流圈地幔的耗散作用.在太阳系内侧5个硅酸质行星中,板块构造仅发育于地球,这表明板块构造是硅酸质行星不太常见的一种热散逸方式.目前还不清楚这种构造活动和热散逸方式在地球上是从何时开始的.所有的硅酸质行星在形成初期可能都经历过一次短暂的岩浆海阶段.行星固结后,静止盖层模式是行星冷却的共同途径,即行星表面形成了一个不易活动的固化盖层,此时内部的热量只能通过拆沉作用、热点火山作用和岩浆浅部侵位等方式进行逃逸.由于地球早期温度较高,通过减压熔融形成的岩石圈结构不同于现代岩石圈,即地球早期岩石圈由厚的洋壳和薄的岩石圈地幔构成.这种岩石圈要产生反向浮力需要非常长的时间,因此地球早期即便有板块构造存在,其规模也比较零星.只有当地球冷却到一定程度,扩张中脊下部减压熔融形成薄的洋壳且大洋岩石圈只需几十个百万年就可以产生反向浮力时,才能形成与现今风格相似的、可持续性的板块构造.板块构造启动时间的认识最终取决于人们对相关地质记录(事件)的研究成果.板块构造的判别依据包括蛇绿岩、蓝片岩、超高压变质带、榴辉岩、被动大陆边缘、转换断层、指示克拉通陆块移动轨迹的古地磁研究以及岩浆岩地球化学和同位素构造判别等等.对地质记录的解释必须综合各方面的信息.本人认为现存的地质事件记录了地球构造随时间演化的过程,即太古代时期构造和岩浆活动剧烈,大约在1.9Ga时开始出现近似的板块构造,在新元古代才开始出现与现代相似的、可持续的、具有深俯冲和板片拖曳特性的板块构造.

关键词：板块构造俯冲前寒武纪地球动力学

晚新生代以来青藏高原东缘的剥蚀过程:来自裂变径迹的证据

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沉积与特提斯地质 2006年第1期26卷 97-102页

作者：张毅李勇周荣军 A.L.Densmore N.j.richardson 成都理工大学油气藏及开发工程国家重点实验室四川成都610059 四川省地震局工程地震研究所四川成都610041 Institute of Geology Department of Earth Sciences

本文以青藏高原东缘的三级地貌(川西高原、龙门山和四川盆地)单元为基础,利用裂变径迹定年数据分区块研究了该地区的晚新生代以来的剥蚀速率。研究结果表明,晚白垩世以来青藏高原东缘经历了一个由平缓到突然加速的剥蚀过程,其转折点为... 详细信息

本文以青藏高原东缘的三级地貌(川西高原、龙门山和四川盆地)单元为基础,利用裂变径迹定年数据分区块研究了该地区的晚新生代以来的剥蚀速率。研究结果表明,晚白垩世以来青藏高原东缘经历了一个由平缓到突然加速的剥蚀过程,其转折点为中新世。在整个时间段内的平均剥蚀速率,川西高原为0.26mm/yr,龙门山为0.72mm/yr,四川盆地为0.20mm/yr。龙门山的剥蚀速率大约是川西高原的2.8倍,间接反映边缘山脉的隆升并不等同于高原内部的隆升,边缘山脉的隆升可能是构造隆升和剥蚀隆升相叠加的结果。

关键词：青藏高原东缘晚新生代裂变径迹剥蚀速率隆升

Microalgae Cultivation Using Offshore Membrane Enclosures for Growing Algae (OMEGA)

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j.urnal of Sustainable Bioenergy Systems 2013年第1期3卷 18-32页

作者： Patrick Wiley Linden Harris Sigrid Reinsch Sasha Tozzi Tsegereda Embaye Kit Clark Brandi McKuin Zbigniew Kolber Russel Adams Hiromi Kagawa Tra-My j.stine richardson j.hn Malinowski Colin Beal Matthew A. Claxton Emil Geiger j.n Rask j. Elliot Campbell j.nathan D. Trent Advanced Organic Methods Penryn USA Department of Chemistry University of California Santa Cruz USA Department of Mechanical Engineering University of Nevada Reno USA Department of Ocean Sciences University of California Santa Cruz USA Dynamac Corporation NASA Ames Research Center Moffett Field USA NASA Ames Research Center Moffett Field USA School of Engineering University of California Merced USA SETI Institute Mountain View USA Universities Space Research Association Columbia USA

OMEGA is a system for cultivating microalgae using wastewater contained in floating photobioreactors (PBRs) deployed in marine environments and thereby eliminating competition with agriculture for water, fertilizer, and land. The offshore placement in protected bays near coastal cities co-locates OMEGA with wastewater outfalls and sources of CO2-rich flue gas on shore. To evaluate the feasibility of OMEGA, microalgae were grown on secondary-treated wastewater supplemented with simulated flue gas (8.5% CO2 V/V) in a 110-liter prototype system tested using a seawater tank. The flow-through system consisted of tubular PBRs made of transparent linear low-density polyethylene, a gas exchange and harvesting column (GEHC), two pumps, and an instrumentation and control (I&C) system. The PBRs contained regularly spaced swirl vanes to create helical flow and mixing for the circulating culture. About 5% of the culture volume was continuously diverted through the GEHC to manage dissolved oxygen concentrations, provide supplemental CO2, harvest microalgae from a settling chamber, and add fresh wastewater to replenish nutrients. The I&C system controlled CO2 inj.ction and recorded dissolved oxygen levels, totalized CO2 flow, temperature, circulation rates, photosynthetic active radiation (PAR), and the photosynthetic efficiency as determined by fast repetition rate fluorometry. In two experimental trials, totaling 23 days in April and May 2012, microalgae productivity averaged 14.1 ± 1.3 grams of dry biomass per square meter of PBR surface area per day (n = 16), supplemental CO2 was converted to biomass with >50% efficiency, and >90% of the ammonia-nitrogen was recovered from secondary effluent. If OMEGA can be optimized for energy efficiency and scaled up economically, it has the potential to contribute significantly to biofuels production and wastewater treatment.

关键词： Biofuels Wastewater Treatment Microalgae Photobioreactor CO2 Mass Transfer Fast Repetition Rate Fluorometry Instrumentation and Control

人HCN4通道的滞后现象:影响窦房结起搏的潜在决定因素(英文)

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生理学报 2010年第1期62卷 1-13页

作者：萧永福 Natalie Chandler Halina Dobrzynski Eric S.richardson Erica M.TenBroek j.shua j.Wilhelm Vinod Sharma Anthony Varghese Mark R.Boyett Paul A.Iaizzo Daniel C.Sigg 美敦力公司心脏节律疾病管理部曼彻斯特大学医学院明尼苏达州大学外科学系明尼苏达州大学整合生物学与生理学系美敦力公司科学技术部威斯康辛大学雷河分校计算机系

超极化活化环核苷酸门控(hyperpolarization-activated cyclic-nucleotide-gated,HCN)通道参与调制心脏跳动的节律和速率。与HCN1和HCN2有所不同,慢通道HCN4可能不存在电压依赖的滞后现象。本研究采用单细胞膜片钳方法,在稳定转染hHCN4... 详细信息

超极化活化环核苷酸门控(hyperpolarization-activated cyclic-nucleotide-gated,HCN)通道参与调制心脏跳动的节律和速率。与HCN1和HCN2有所不同,慢通道HCN4可能不存在电压依赖的滞后现象。本研究采用单细胞膜片钳方法,在稳定转染hHCN4的HEK293细胞上进行电生理记录,观察hHCN4通道是否存在滞后现象,以及cAMP对其的调制作用;同时采用实时定量RT-PCR方法检测窦房结和心房组织中HCNs的表达。电压钳实验结果显示hHCN4电流(Ih)激活随着保持电位超极化的变化而向去极化方向移动。三角电位变化钳(triangular ramp)和动作电位钳的结果也显示了hHCN4的滞后现象。cAMP增加Ih电流幅度,且使电流激活向去极化方向移动,从而改变内源性hHCN4滞后行为。RT-PCR结果显示,人窦房结组织主要表达HCN4,占75%,HCN1占21%,HCN2占3%,HCN3占0.7%。以上结果提示,人窦房结组织主要表达HCN4亚型,hHCN4的Ih存在电压依赖性的滞后现象,且受cAMP调制。由此推断,hHCN4通道的滞后现象可能在窦房结起搏活动中起到了关键作用。

关键词： HCN4通道滞后窦房结 cAMP

The Orosirian(1800–2050 Ma)plate tectonic episode:Key for reconstructing the Proterozoic tectonic record

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Geoscience Frontiers 2023年第3期14卷 1-9页

作者： Robert j.Stern Geosciences Dept. U Texas at DallasRichardsonTX 75083-0688United States

Eight lines of evidence indicate that the Orosirian Period in mid-Paleoproterozoic time was characterized by plate tectonics:ophiolites,low T/P metamorphism including eclogites,passive margin formation,tall mountains,paleomagnetic constraints,ore deposits,abundant S-type granites,and seismic images of paleo-subduction *** plate tectonic episode occurred about 1 billion years earlier than the present plate tectonic episode began in Neoproterozoic *** two plate tectonic episodes bracket the‘Boring Billion’,which may have been a protracted single lid tectonic episode that began when the supercontinent Nuna or Columbia *** of multiple lines of evidence for Orosirian plate tectonics demonstrates that Earth’s tectonic style can be reconstructed with some confidence back to at least Early Paleoproterozoic time,and thus the absence of compelling evidence for Mesoproterozoic plate tectonics is not obvious due to poor preservation.A tectono-magmatic lull2.3 Ga suggests an earlier episode of single lid *** for two episodes of plate tectonics and two episodes of single lid tectonics indicates that Earth switched between single lid and plate tectonics multiple times during the last 2.4 Ga.

关键词： Plate tectonics Single lid tectonics Urey ratio Paleoproterozoic

对一个大单轴磁各向异性镍(Ⅱ)配合物中的磁跃迁的直接观察

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无机化学学报 2020年第6期36卷 1149-1156页

作者： Chelsea N.Widener Alexandria N.Bone Mykhaylo Ozerov Rachael richardson 路正光 Komalavalli Thirunavukkuarasu Dmitry Smirnov 陈学太薛子陵田纳西大学化学系诺克斯维尔市37996美国国家高磁场实验室佛罗里达州立大学塔拉哈西市32310美国佛罗里达农工大学物理系塔拉哈西市32307美国南京大学化学化工学院配位化学国家重点实验室南京210023

最近Ruamps和同事发现三角双锥构型的Ni(Ⅱ)配合物[Ni(Me6tren)Cl]ClO4(1,Me6tren=tris(2-(dimethylamino)ethyl)amine)具有大的单轴磁各向异性(j. Am. Chem. Soc., 2013,135:3017-3026)。他们利用HF-EPR研究获得横向零场分裂(ZFS)参数E=1.56(5)cm-1但未能确定轴向零场分裂参数D。在本工作中,我们利用0~17.5 T和5 K的变磁场远红外光谱(FIRMS)来检测自旋基态S=1中的MS=±1和MS=0态之间的磁跃迁。在FIRMS中直接观察到Zeeman分裂态之间的跃迁,得出轴向ZFS参数D=-110.7(3) cm-1。我们对1的晶体结构进行了Hirshfeld表面分析,揭示了1分子中的阳离子与阴离子之间以及分子之间的相互作用。

关键词：镍配合物零场分裂磁跃迁单轴磁各向异性远红外光谱