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Expression of structural genes related to anthocyanin biosynthesis of Vitis amurensis 被引量:1
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作者 Quan Zhao Fei He +3 位作者 Malcolm J.Reeves Qiu-Hong Pan Chang-Qing Duan Jun Wang 《Journal of Forestry Research》 SCIE CAS CSCD 2016年第3期647-657,共11页
This research was designed to assess the changes in anthocyanin content in grape skins of Vitis amurensis and to explore m RNA transcriptions of 11 structural genes(PAL,CHS3, CHI1, F3H2, F30 H, F3050 H, DFR, LDOX, UFG... This research was designed to assess the changes in anthocyanin content in grape skins of Vitis amurensis and to explore m RNA transcriptions of 11 structural genes(PAL,CHS3, CHI1, F3H2, F30 H, F3050 H, DFR, LDOX, UFGT,OMT and GST) related to anthocyanin biosynthesis during grape berry development, by the use of HPLC-MS/MS and real-time Q-PCR analysis. Accumulation of anthocyanins began at veraison, continued throughout the later berry development and reached a peak at maturity. Veraison is the time when the berries turn from green to purple. Expression of PAL, CHI1, and LDOX were up-regulated from 2 to4 weeks after flowering(WAF), down-regulated from6 WAF to veraison, whereas DFR was up-regulated at8 WAF, and then up-regulated from veraison to maturity.CHS3, F3050 H, UFGT, GST, and OMT were down-regulated from 2 WAF to veraison, and then up-regulated from veraison to maturity. The transcriptional expressions of the11 structural genes also showed positive correlations with the anthocyanin content from veraison to maturity. Positive correlations were also observed between OMT transcriptional level and the content of methoxyl-anthocyanins, and between F3050 H transcriptional level and the content of delphinidin anthocyanins. F3H2 and F30 H expression was up-regulated at 2 WAF. F3H2 expression was down-regulated from 4 WAF to veraison and then up-regulated again from veraison to maturity. F30 H expression was down-regulated at 4 WAF and then up-regulated again from 6 WAF to maturity. F30 H transcriptional level was correlated positively with the cyanidin anthocyanin concentration from veraison to maturity. These results indicate that the onset of anthocyanin synthesis during berry development coincides with a coordinated increase in the expression of a number of genes in the anthocyanin biosynthetic pathway. 展开更多
关键词 生物合成途径 结构基因 花色苷 山葡萄 高效液相色谱-质谱法 花青素含量 花色素苷 葡萄浆果
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Timing of Crop Removal Has Limited Effect on Merlot Grape and Wine Composition
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作者 Petra D. King Richard E. Smart Daniel J. McClellan 《Agricultural Sciences》 2015年第4期456-465,共10页
Cluster removal during the growing season is a widely utilized vineyard management practice aiming to balance crop load to the capacity of the vine to ripen the fruit. Research was undertaken over two growing seasons ... Cluster removal during the growing season is a widely utilized vineyard management practice aiming to balance crop load to the capacity of the vine to ripen the fruit. Research was undertaken over two growing seasons (2008-2009) in Hawke’s Bay, a cool climate region of New Zealand, to establish the influence of different times of crop removal on Merlot vine growth and fruit and wine composition. The test vineyard was high-yielding, to 23 t/ha, and vigorous. A commercial standard of apical cluster thinning to remove 20 clusters per vine from vines with ca 44 clusters in 2008 and ca 47 in 2009, was carried out on uniform vigour, 7yo grafted Merlot vines at nine times between prebloom and six weeks post veraison. The 2009 season was naturally higher yielding. Timing of crop removal had no significant effect on vine vegetative growth in terms of enhanced shoot growth as measured by cane weights at pruning, or canopy leaf density. Time of thinning also had no effect on overall grape yield, cluster weight, and berry weight. There were limited effects on fruit ripeness in one season (2009) at the veraison time of thinning only, with increased Brix and lower TA levels. Berry anthocyanin concentrations were enhanced by cluster thinning in 2008, and more so when undertaken at or soon after veraison. There was however no influence of removal timing on anthocyanin levels and total phenolics in the wines. Grape ripeness, must and wine composition tended to respond more from crop removal at veraison than the other times evaluated. Data suggest that vine response was modified by excessive leafiness and shading. 展开更多
关键词 CROP Removal TIMING MERLOT GRAPE COMPOSITION WINE
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Labour and Multi-factor Productivity Analysis and Their Impact on Operations: A Case Study of a Large Poultry Farm
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作者 Ram Roy 《Management Studies》 2015年第6期263-272,共10页
关键词 管理学 管理学理论 管理技术 管理方法
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Ambiently fostering solid electrolyte interphase for low-temperature lithium metal batteries
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作者 Jia-Yue Duan Jin-Xiu Chen +7 位作者 Fang-Fang Wang Jin-Hao Zhang Xiao-Zhong Fan Liping Wang Yingze Song Wei Xia Yusheng Zhao Long Kong 《Journal of Energy Chemistry》 SCIE EI CSCD 2023年第12期473-478,I0012,共7页
Despite being a leading candidate to meet stringent energy targets,lithium(Li) metal batteries(LMBs)face severe challenges at low temperatures such as dramatic increase in impedance,capacity loss and dendrite growth.U... Despite being a leading candidate to meet stringent energy targets,lithium(Li) metal batteries(LMBs)face severe challenges at low temperatures such as dramatic increase in impedance,capacity loss and dendrite growth.Unambiguously fingerprinting rate-limited factors of low-temperature LMBs would encourage targeted approaches to promote performances.Herein,the charge transfer impedance across solid electrolyte interphase(SEI) is identified to restrict battery operation under low temperature,and we propose a facile approach on the basis of ambiently fostering SEI(af-SEI) to facilitate charge transfer.The concept of af-SEI stems from kinetic benefits and structural merits to construct SEI at ambient temperature over low temperature developed SEI that is temporally consuming to achieve steady state and that is structurally defective to incur dendrite growth.The af-SEI allows ionically conductive and morphologically uniform layer on the anode surface,which exhibits a lower resistance and induces an even deposition of Li in the subsequent low temperature battery operation.Armed with af-SEI,the LMBs deliver the improved rate performance and prolonged cycle life when subjected to low temperature cycling.This work unveils the underlying causes that limit low temperature LMB performances,and enlightens the facile test protocols to build up favorable SEI,beyond scope of material and morphology design. 展开更多
关键词 Li matel batteries Ambiently fostering SEI Charge transfer impedance Low temperature kinetics
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Optical colorimetric LiTaO_(3)wafers for highprecision lithography on frequency control of SAW devices
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作者 MING HUI FANG YINONG XIE +9 位作者 FANGQI XUE ZHILIN WU JUN SHI SHENG YU YANG YILIN LIU ZHIHUANG LIU HSIN CHI WANG FAJUN LI QING HUO LIU JINFENG ZHU 《Photonics Research》 SCIE EI CAS CSCD 2024年第2期341-349,共9页
Surface acoustic wave(SAW)resonators based on lithium tantalate(LT,LiTaO_(3))wafers are crucial elements of mobile communication filters.The use of intrinsic LT wafers typically brings about low fabrication accuracy o... Surface acoustic wave(SAW)resonators based on lithium tantalate(LT,LiTaO_(3))wafers are crucial elements of mobile communication filters.The use of intrinsic LT wafers typically brings about low fabrication accuracy of SAW resonators due to strong UV reflection in the lithography process.This hinders their resonance frequency control seriously in industrial manufacture.LT doping and chemical reduction could be applied to decrease the UV reflection of LT wafers for high lithographic precision.However,conventional methods fail to provide a fast and nondestructive approach to identify the UV performance of standard single-side polished LT wafers for highprecision frequency control.Here,we propose a convenient on-line sensing scheme based on the colorimetry of reduced Fe-doped LT wafers and build up an automatic testing system for industrial applications.The levels of Fe doping and chemical reduction are evaluated by the lightness and color difference of LT-based wafers.The correlation between the wafer visible colorimetry and UV reflection is established to refine the lithography process and specifically manipulate the frequency performance of SAW resonators.Our study provides a powerful tool for the fabrication control of SAW resonators and will inspire more applications on sophisticated devices of mobile communication. 展开更多
关键词 LITHOGRAPHY DOPING WAFER
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MOF-mediated synthesis of novel PtFeCoNiMn high-entropy nanoalloy as bifunctional oxygen electrocatalysts for zinc-air battery
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作者 Mingkuan Xie Xin Xiao +7 位作者 Duojie Wu Cheng Zhen Chunsheng Wu Wenjuan Wang Hao Nian Fayan Li Meng Danny Gu Qiang Xu 《Nano Research》 SCIE EI CSCD 2024年第6期5288-5297,共10页
High-entropy alloy(HEA)-based materials are expected to be promising oxygen electrocatalysts due to their exceptional properties.The electronic structure regulation of HEAs plays a pivotal role in enhancing their elct... High-entropy alloy(HEA)-based materials are expected to be promising oxygen electrocatalysts due to their exceptional properties.The electronic structure regulation of HEAs plays a pivotal role in enhancing their elctrocatalytic ability.Herein,PtFeCoNiMn nanoparticles(NPs)with subtle lattice distortions are constructed on metal-organic framework-derived nitrogen-doped carbon by an ultra-rapid Joule heating process.Thanks to the modulated electronic structure and the inherent cocktail effect of HEAs,the as-synthesized PtFeCoNiMn/NC exhibits superior bifunctional electrocatalytic performance with a positive half-wave potential of 0.863 V vs.reversible hydrogen electrode(RHE)for oxygen reduction reaction and a low overpotential of 357 mV at 10 mA·cm^(-2)for oxygen evolution reaction.The assembled quasi-solid-state zinc-air battery using PtFeCoNiMn/NC as air electrode shows a high peak power density of 192.16 mW·cm^(-2),low charge−discharge voltage gap,and excellent durability over 500 cycles at 5 mA·cm^(-2).This work demonstrates an effective route for rational design of bifunctional nanostructured HEA electrocatalysts with favorable electronic structures,and opens up a fascinating directions for energy storage and conversion,and beyond. 展开更多
关键词 oxygen reduction reaction oxygen evolution reaction high-entropy nano-alloy zinc-air battery
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Discovery of Partial Differential Equations from Highly Noisy and Sparse Data with Physics-Informed Information Criterion
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作者 Hao Xu Junsheng Zeng Dongxiao Zhang 《Research》 SCIE EI CSCD 2024年第1期247-259,共13页
Data-driven discovery of partial differential equations(PDEs)has recently made tremendous progress,and many canonical PDEs have been discovered successfully for proof of concept.However,determining the most proper PDE... Data-driven discovery of partial differential equations(PDEs)has recently made tremendous progress,and many canonical PDEs have been discovered successfully for proof of concept.However,determining the most proper PDE without prior references remains challenging in terms of practical applications.In this work,a physics-informed information criterion(PIC)is proposed to measure the parsimony and precision of the discovered PDE synthetically.The proposed PIC achieves satisfactory robustness to highly noisy and sparse data on 7 canonical PDEs from different physical scenes,which confirms its ability to handle difficult situations.The PIC is also employed to discover unrevealed macroscale governing equations from microscopic simulation data in an actual physical scene.The results show that the discovered macroscale PDE is precise and parsimonious and satisfies underlying symmetries,which facilitates understanding and simulation of the physical process.The proposition of the PIC enables practical applications of PDE discovery in discovering unrevealed governing equations in broader physical scenes. 展开更多
关键词 process. CANONICAL PROOF
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The Spectral Integral Method(SIM)for the Scattering from an Arbitrary Number of Circular PEC Cylinders
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作者 Qing Huo Liu Siwei Wan Chunhui Zhu 《Electromagnetic Science》 2023年第4期32-40,共9页
We present an accurate spectral integral method(SIM)for the analyses of scattering from multiple circular perfect electric conductor(PEC)cylinders.It solves the coupled surface integral equations by using the Fourier ... We present an accurate spectral integral method(SIM)for the analyses of scattering from multiple circular perfect electric conductor(PEC)cylinders.It solves the coupled surface integral equations by using the Fourier series and addition theorem to decouple the system.The SIM has exponential convergence so that the error decreases exponentially with the sample density on the surfaces,and requires only about 2–3 points per wavelength(PPW)to reach engineering accuracy defined as higher than 99%accuracy(or with an error smaller than 1%).Numerical results demonstrate that the SIM is much more accurate and efficient than the method of moments(MoM),and thus can be potentially used as the exact radiation boundary condition in the finite element and spectral element methods. 展开更多
关键词 Method of moments Multiple cylinders SCATTERING Spectral integral method
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Coverage in Cooperative LEO Satellite Networks
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作者 Bodong Shang Xiangyu Li +1 位作者 Caiguo Li Zhuhang Li 《Journal of Communications and Information Networks》 EI CSCD 2023年第4期329-340,共12页
Low-earth orbit(LEO)satellite networks ignite global wireless connectivity.However,signal outages and co-channel interference limit the coverage in traditional LEO satellite networks where a user is served by a single... Low-earth orbit(LEO)satellite networks ignite global wireless connectivity.However,signal outages and co-channel interference limit the coverage in traditional LEO satellite networks where a user is served by a single satellite.This paper explores the possibility of satellite cooperation in the downlink transmissions.Using tools from stochastic geometry,we model and analyze the downlink coverage of a typical user with satellite cooperation under Nakagami fading channels.Moreover,we derive the joint distance distribution of cooperative LEO satellites to the typical user.Our model incorporates fading channels,cooperation among several satellites,satellites'density and altitude,and co-channel interference.Extensive Monte Carlo simulations are performed to validate analytical results.Simulation and numerical results suggest that coverage with LEO satellites cooperation considerably exceeds coverage without cooperation.Moreover,there are optimal satellite density and satellite altitude that maximize the coverage probability,which gives valuable network design insights. 展开更多
关键词 Low-earth orbit satellite cooperative communications coverage probability satellite-terrestrial networks non-terrestrial networks
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Transforming organic chemistry research paradigms:Moving from manual efforts to the intersection of automation and artificial intelligence
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作者 Chengchun Liu Yuntian Chen Fanyang Mo 《National Science Open》 2024年第2期98-127,共30页
Organic chemistry is undergoing a major paradigm shift,moving from a labor-intensive approach to a new era dominated by automation and artificial intelligence(AI).This transformative shift is being driven by technolog... Organic chemistry is undergoing a major paradigm shift,moving from a labor-intensive approach to a new era dominated by automation and artificial intelligence(AI).This transformative shift is being driven by technological advances,the ever-increasing demand for greater research efficiency and accuracy,and the burgeoning growth of interdisciplinary research.AI models,supported by computational power and algorithms,are drastically reshaping synthetic planning and introducing groundbreaking ways to tackle complex molecular synthesis.In addition,autonomous robotic systems are rapidly accelerating the pace of discovery by performing tedious tasks with unprecedented speed and precision.This article examines the multiple opportunities and challenges presented by this paradigm shift and explores its far-reaching implications.It provides valuable insights into the future trajectory of organic chemistry research,which is increasingly defined by the synergistic interaction of automation and AI. 展开更多
关键词 organic chemistry automation platform artificial intelligence algorithms
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