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Warmer temperature during asexual reproduction induce methylome, transcriptomic, and lasting phenotypic changes in Fragaria vesca ecotypes

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Horticulture Research 2023年第9期10卷 121-135页

作者：张宇鹏 Guangxun Fan Tuomas Toivainen Torstein Tengs Igor Yakovlev Paal Krokene Timo Hytönen carl Gunnar Fossdal Paul E.Grini EVOGENE Department of BiosciencesUniversity of Oslo0313 OsloNorway Department of Molecular Plant Biology Norwegian Institute of Bioeconomy Research1431ÅsNorway Department of Agricultural Sciences Viikki Plant Science CentreUniversity of Helsinki00014 HelsinkiFinland

Plants must adapt with increasing speed to global warming to maintain their *** rapid adaptation mechanism is epigenetic memory,which may provide organisms sufficient time to adapt to climate *** studied how the perennial Fragaria vesca adapted to warmer temperatures(28◦c vs.18◦c)over three asexual *** in flowering time,stolon number,and petiole length were induced by warmer temperature in one or more ecotypes after three asexual generations and persisted in a common garden *** methylome changes differed between the four ecotypes from Norway,Iceland,Italy,and Spain,but shared methylome responses were also *** differentially methylated regions(DMRs)occurred in the cHG context,and most cHG and cHH DMRs were hypermethylated at the warmer *** eight cHG DMR peaks,a highly similar methylation pattern could be observed between *** average,13%of the differentially methylated genes between ecotypes also showed a temperature-induced change in gene *** observed ecotype-specific methylation and expression patterns for genes related to gibberellin metabolism,flowering time,and epigenetic ***,we observed a negative correlation with gene expression when repetitive elements were found near(±2 kb)or inside *** conclusion,lasting phenotypic changes indicative of an epigenetic memory were induced by warmer temperature and were accompanied by changes in DNA methylation *** shared methylation patterns and transcriptome differences between *** accessions were observed,indicating that DNA methylation may be involved in both general and ecotype-specific phenotypic variation.

关键词： metabolism maintain adapted

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Production of the cancer-Preventive Glucoraphanin in Tobacco

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Molecular Plant 2010年第4期3卷 751-759页

作者： Michael Dalgaard Mikkelsen carl Erik Olsen Barbara Ann Halkier University of copenhagen Faculty of Life Sciences Department of Plant Biology Plant Biochemistry Laboratory VKR Research Centre for Pro-Active Plants 40 Thorvaldsensvej DK-1871 Frederiksberg C Copenhagen Denmark University of copenhagen Faculty of Life Sciences Department of Basic Sciences and Environment/Bioorganic Chemistry 40 Thorvaldsensvej DK-1871 Frederiksberg C Copenhagen Denmark

Epidemiological studies have demonstrated reduced risk of developing cancer upon consumption of diets rich in cruciferous vegetables. This chemoprevention has been largely attributed to the presence of the natural products glu- cosinolates, particularly the methionine-derived glucoraphanin from broccoli. Improved nutrition by functional foods or health-promoting dietary supplements is an attractive means for prevention of lifestyle-based diseases. Towards this goal, we have engineered the glucoraphanin pathway into tobacco. First, we engineered elongation of the side chain of methionine to produce the key intermediate dihomo-methionine. This process is catalyzed through two cycles in a chain-elongation pathway that takes place partly in the cytosol and partly in the chloroplast. Second, by coupling the five enzymes of the chain-elongation pathway to eight enzymes of the glucosinolate pathway, we show production of glucoraphanin together with other glucosinolates derived from chain-elongated isoleucine and/or leucine. The conver- sion of methionine to glucoraphanin is obtained via 14 intermediates. Demonstrating the production of the high-value glucoraphanin in a heterologous host has great potential in the food and medicinal industry as a means to generate a stable, rich source of glucoraphanin for the benefit of human health.

关键词： compartmentation secondary metabolism/natural products Agrobacterium Arabidopsis tobacco glucosinolates metabolic engineering.

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Modeling the impacts of climate variability and hurricane on carbon sequestration in a coastal forested wetland in South carolina

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Natural Science 2013年第3期5卷 375-388页

作者： Zhaohua Dai carl c. Trettin changsheng Li Ge Sun Devendra M. Amatya Harbin Li center for Forested Wetland Research USDA Forest Service Cordesville USA Earth Science Research center EOS University of New Hampshire Durham US Earth Science Research center EOS University of New Hampshire Durham USA Eastern Forest Environmental Threat Assessment center Southern Research Station USDA Forest Service Raleigh USA

The impacts of hurricane disturbance and climate variability on carbon dynamics in a coastal forested wetland in South carolina of USA were simulated using the Forest-DNDc model with a spatially explicit approach. The model was validated using the measured biomass before and after Hurricane Hugo and the biomass inventories in 2006 and 2007, showed that the Forest- DNDc model was applicable for estimating carbon dynamics with hurricane disturbance. The simulated results indicated that Hurricane Hugo in 1989 substantially influenced carbon storage immediately after the disturbance event. The simulated net ecosystem exchange (NEE) for the 58-year period (1950-2007) indicated that the hurricane reduced cO2 sequestration due primarily to the increased decomposition of a large amount of litter and woody debris, including fallen trees (over 80% of pre-hurricane trees), debris and branches, and dead roots. The inter-annual fluctuation of soil cO2 flux showed that the climate variability interfered substantially soil carbon dynamics in the forest. The results showed that there were substantial spatial and temporal differences in cO2 flux (3.2 - 4.8 Mg·c·ha–1) and wood biomass due to the differences in physical and biogeochemical characteristics in the forest.

关键词： Greenhouse Gas Forest-DNDc Biogeochemical Model Biomass climate change

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低温加氢催化剂的设计：理论与实践(英文)

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物理化学学报 2010年第4期26卷 869-876页

作者：陈经广齐随涛 HUMBERT Michael P MENNING carl A 朱月香 Department of chemical Engineering Center for Catalytic Science and Technology(CCST)University of DelawareNewarkDE 19716USA 西安交通大学化工系西安710049 北京大学化学与分子工程学院北京分子科学国家实验室分子动态与稳态结构国家重点实验室北京100871

简要总结了我们在c=c及c=O双键低温加氢双金属催化剂方面的最新研究成果.首先,我们以环己烯加氢为探针反应,证明了平行使用多种研究手段的重要性,包括单晶表面的基础研究与DFT计算,多晶表面的合成与表征,负载型催化剂的制备与性能测试等... 详细信息

简要总结了我们在c=c及c=O双键低温加氢双金属催化剂方面的最新研究成果.首先,我们以环己烯加氢为探针反应,证明了平行使用多种研究手段的重要性,包括单晶表面的基础研究与DFT计算,多晶表面的合成与表征,负载型催化剂的制备与性能测试等.其次,总结了双金属催化剂在其他加氢反应,如丙烯醛c=O双键的选择性加氢,苯的低温加氢,以及乙炔的选择性加氢等反应中的应用.最后,讨论了利用金属碳化物代替贵金属Pt以减少双金属催化剂中Pt用量的可能性.

关键词：加氢双金属催化剂金属碳化物 DFT计算

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Stochastic contrast Measures for SAR Data: A Survey

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雷达学报（中英文） 2019年第6期8卷 758-781页

作者： Alejandro c.Frery La ccAN–Laboratório de computa??o científica e Análise Numérica Universidade Federal de Alagoas

“contrast”is an generic denomination for“difference”.Measures of contrast are a powerful tool in image processing and analysis,e.g.,in denoising,edge detection,segmentation,classification,parameter estimation,change detection,and feature *** present a survey on techniques that aim at measuring the contrast between(i)samples of SAR imagery,and(ii)samples and models,with emphasis on those that employ the statistical properties of the data.

关键词： contrast Divergence Entropy Geodesic distance Statistics Synthetic Aperture Radar(SAR)

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Pressurized Liquid Extraction of Pigments from chlamydomonas *** chemical characterization by HPLc–MS/MS

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Journal of Analysis and Testing 2018年第2期2卷 149-157页

作者： Lidia Montero Mahshid Sedghi Yolanda García carlos Almeida carl Safi Nicole Engelen‑Smit Alejandro cifuentes Jose A.Mendiola Elena Ibáñez Applied Analytical chemistry University of Duisburg-EssenUniversitaetsstr.545141 EssenGermany Laboratory of Foodomics Bioactivity and Food Analysis DepartmentInstitute of Food Science Research CIAL(CSIC-UAM)Campus de CantoblancoC/Nicolás Cabrera 928049 MadridSpain Spanish Bank of Algae Instituto de Oceanografía y Cambio GlobalFundación Canaria Parque Científico‑TecnológicoUniversidad de Las Palmas de Gran CanariaMuelle de Taliarte s/n35214 Telde(Canary Islands)Spain Wageningen Food and Biobased Research Wageningen University and ResearchPO Box 176700 AA WageningenThe Netherlands

Pressurized liquid extraction using green solvents(ethanol and water)was applied to extract photosynthetic pigments from the microalgae chlamydomonas *** experimental design is employed to determine the effect of the extraction conditions on the extraction yield and the antioxidant capacity of the different extracts determined using 1,1-diphenyl-2-picryl-hydrazyl and TEAc *** the extracts show significant antioxidant activity in all ***,in this work,the carotenoid and chlorophyll composition of the chlamydomonas extracts was analyzed by HPLc–DAD–APcI–MS/MS for the first time,being the main compounds lutein and pheophythin a′.

关键词： Antioxidant capacity chlamydomonas sp. HPLc–DAD–APcI–MS/MS Pigments Pressurized liquid extraction carotenoids

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Enhanced cell-edge Performance with Transmit Power-Shaping and Multipoint, Multiflow Techniques

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ZTE communications 2011年第4期9卷 43-48页

作者： Philip Pietraski Gregg charlton carl Wang InterDigital communications LLC. King Of PrussiaPA19406 U. S. A.

In this paper, we present a technique called ＂fuzzy cells＂ that builds on the multicarrier features of Long Term Evolution-Advanced （LTE-A） and high-speed packet access （HSPA）. Multiple carriers are aggregated to create a larger system bandwidth, and these carriers are transmitted at different powers by each sector antenna. This creates a set of cell-edge locations that differ from one frequency to the next. System-level simulations are performed to estimate individual user and average throughput for a hexagonal deployment of 3-sector base stations. For moderately high loads, a fuzzy cell deployment can improve tenth percentile （cell-edge） user throughput by 100% and can improve average throughput by about 30% compared with a reuse 1 scheme. Fuzzy ceils reduce inter-cell interference in the same way as higher-order reuse schemes and allow users to access the full system bandwidth.

关键词： LTE fractional frequency reuse multicarrier flow aggregation system simulation

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海绵窦的内镜解剖以及手术入路

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中华耳鼻咽喉头颈外科杂志 2013年第11期48卷 901-907页

作者：刘剑锋曲秋懿杨大章韩军张秋航 carl H.Snyderman Juan c.Fernandez-Miranda Paul A.Gardner 中日友好医院耳鼻咽喉科北京100029 首都医科大学宣武医院颅底外科中心美国匹兹堡大学医学中心颅底外科中心

目的探讨内镜下海绵窦的解剖特点以及手术入路.方法 6例（12侧）新鲜尸头,有色硅胶灌注血管.行内镜经鼻-蝶入路和经筛-翼-蝶入路,完成蝶窦开放,蝶窦后壁切除,翼突部分切除和蝶窦外侧壁切除.充分暴露海绵窦及其周围结构.应用Stroz Imag... 详细信息

目的探讨内镜下海绵窦的解剖特点以及手术入路.方法 6例（12侧）新鲜尸头,有色硅胶灌注血管.行内镜经鼻-蝶入路和经筛-翼-蝶入路,完成蝶窦开放,蝶窦后壁切除,翼突部分切除和蝶窦外侧壁切除.充分暴露海绵窦及其周围结构.应用Stroz Image l高清系统采集图像.结果颈内动脉海绵窦段穿行海绵窦将海绵窦分为5个部分,即内侧海绵窦、外侧海绵窦、海绵窦后上腔隙、海绵窦后下腔隙和海绵窦前下腔隙.海绵窦段颈内动脉的分支包括：脑膜垂体干、Mcconnell包膜动脉和下外侧干.颅神经Ⅲ、Ⅳ走行于海绵窦外侧壁的上部；颅神经Ⅴ1自Meckel腔向眶上裂斜行；颅神经Ⅵ自海绵窦后下腔隙底部从颈内动脉后膝部的内侧绕行到外侧,穿过海绵窦窦腔,向外上前至眶上裂.内镜经鼻海绵窦手术入路分为经蝶-鞍-内侧海绵窦入路（颈内动脉内侧入路）和经筛-翼-蝶-外侧海绵窦入路（颈内动脉外侧入路）.前者可以暴露海绵窦段颈内动脉的内侧部,部分海绵窦后上、后下腔隙.后者可以暴露海绵窦前下腔隙、外侧海绵窦以及外侧壁的颅神经.结论海绵窦的解剖非常复杂,颈内动脉以及颅神经Ⅲ、Ⅳ、Ⅴ1、Ⅵ穿行其内,与周同重要静脉窦相交通.熟悉掌握内镜下海绵窦解剖以及手术入路对于内镜下处理海绵窦以及海绵窦相关的病变有重要意义.

关键词：海绵窦内窥镜检查耳鼻喉外科手术颅底蝶鞍解剖学,局部

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Numerical Study on the Influence Mechanism of Inlet Distortion on the Stall Margin in a Transonic Axial Rotor

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Journal of Thermal Science 2012年第3期21卷 209-214页

作者： Scott c.Morris Hessert Laboratory Department of Mechanical and Aerospace EngineeringUniversity of Notre Dame

A numerical study is conducted to investigate the influence of inlet flow condition on tip leakage flow (TLF) and stall margin in a transonic axial rotor.A commercial software package FLUENT,is used in the *** rotor investigated in this paper is ND_TAc rotor,which is the rotor of one-stage transonic compressor in the University of Notre *** varied inlet flow conditions are *** inlet boundary condition with hub distortion provides higher axial velocity for the incoming flow near tip region than that for the clean inflow,while the incoming main flow possesses lower axial velocity near the tip region at tip distortion inlet boundary *** the total pressure ratio curves for the three inlet flow conditions,it is found that the hub dis-torted inlet boundary condition improves the stall margin,while the tip distorted inlet boundary condition dete-riorates compressor *** axial location of interface between tip leakage flow (TLF) and incoming main flow (MF) in the tip gap and the axial momentum ratio of TLF to MF are further *** is demonstrated that the axial momentum balance is the mechanism for interface *** hub distorted inflow could de-crease the axial momentum ratio,suppress the movement of the interface between TLF and MF towards blade leading edge plane and thus enhance compressor stability.

关键词： Inlet distortion tip leakage flow stall margin axial momentum balance

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喷流对飞机尾流涡影响的试验研究

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航空学报 2010年第5期31卷 899-908页

作者：黄烁桥申功忻 Robert Konrath carl F.v. carmer Kompenhans Jurgen 北京航空航天大学航空科学与工程学院北京100191 德国宇航院气动与流动技术研究所哥廷根37073

飞机产生的尾流涡,特别是大尺度的翼尖涡,对尾随其后的飞行器是非常有害的,本文旨在探索利用飞机发动机产生的喷流加速尾流涡消亡的方法。试验采用简化的飞机模型(有尾翼),建立了包含一对翼尖涡及一对反向旋转的尾翼涡(通过以负迎角安... 详细信息

飞机产生的尾流涡,特别是大尺度的翼尖涡,对尾随其后的飞行器是非常有害的,本文旨在探索利用飞机发动机产生的喷流加速尾流涡消亡的方法。试验采用简化的飞机模型(有尾翼),建立了包含一对翼尖涡及一对反向旋转的尾翼涡(通过以负迎角安装尾翼得到)的4涡尾流系统。在无外来扰动的情况下,不同的尾翼设置下得到的尾翼涡对翼尖涡的作用效果不同,有的能导致翼尖涡提前消亡,有的则不能。考察了不同强度的喷流对不同4涡尾流系统的影响,且作为对比,对无尾翼(2涡系统)及无喷流下的各种情况也分别作了观测。试验在拖曳水槽中进行,运用体视粒子图像测速(SPIV)技术,观测了与模型拖曳方向垂直的、从机翼后缘到下游约45翼展间均布的一系列切面。结果表明:当喷流直接作用于涡时,其效果主要取决于两者之间的初始距离及相对强度;而当喷流作用于整个4涡尾流系统时,其引入的扰动对不同的系统均能起到一定程度的改善作用,这种作用的关键在于利用喷流优化对翼尖涡进行扰动的机制,而不仅仅取决于喷流的强度。

关键词：流体力学飞机尾流喷流体视粒子图像测速

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