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| 1 | DMM:A dynamic memory mapping model for virtual machines显示文摘Memory virtualization is an important part in the design of virtual machine monitors(VMM).In this paper,we proposed dynamic memory mapping(DMM) model,a mechanism that allows the VMM to change the mapping between a virtual machine's physical memory and the underlying hardware resource while the virtual machine is running.By utilizing DMM,the VMM can implement many novel memory management policies,such as Demand Paging,Swapping,Ballooning,Memory Sharing and Copy-On-Write,while preserving compatibility with various architectures.The modular and hierarchical property of the DMM model efficiently incorporates the high-level policies and the low-level implementations,leading to a feature-adjustable VMM design.We presented the principle of the DMM model,and explained the procedures of various memory management policies under this model.Also,we implement the DMM model in KVM,an open source VMM.Our evaluation shows that the DMM model is efficient enough to provide the benefits of dynamic memory resource management with little performance impact. | CHEN HaoGang WANG XiaoLin WANG ZhenLin ZHANG BinBin LUO YingWei LI XiaoMing | 2010 | Science China(Information Sciences)2010，53，6： | 11 |
| 2 | Exogenous abscisic acid coordinating leaf senescence and transport of assimilates into wheat grains under drought stress by regulating hormones homeostasis显示文摘Drought at the grain filling stage of wheat will cause premature leaf senescence, thus leading to considerable loss of wheat yield. Therefore, this paper aims to establish a cultivation technology for strong drought resistance, delayed senescence, and yield improvement based on the analysis of hormones homeostasis obtained by applying chemical control substances. Experiments were conducted with two genotypes of wheat. Four water irrigation treatments were applied to impose the water deficit, including well-watered control treatment(WW), mild water deficit(MiWD), moderate water deficit(MoWD), and severe water deficit(SWD). Exogenous abscisic acid(ABA) was sprayed on the plants at the anthesis stage of the wheat. As a result, exogenous ABA reduced initial senescence rate(r0), total duration of chlorophyll(Chltotal), rapid senescence phase(Chlloss), and the accumulated temperature at an inflection point(M) but improved the persistence phase(Chlper) of flag leaves under all of the four treatments. However, exogenous ABA produced inconsistent effects on photoassimilate relocation and grain weight under different treatments. It produced positive regulatory effects on grain weight under WW, MiWD, and MoWD treatments. On the one hand, spraying ABA during the persistence phase of flag leaves reduced the ratios of zeatin to gibberellin(Z/GA3), spermine to spermidine(Spm/Spd), and salicylic acid to ABA(SA/ABA),which prolonged active photosynthesis by stimulating high level of proline(Pro) and increased the activities of antioxidant enzymes, such as superoxide dismutase(SOD), peroxidase(POD), catalase(CAT), and ascorbate peroxidase(APX). Therefore, drought tolerance was enhanced, and more photosynthetic assimilates were accumulated. On the other hand, the rapid senescence phase and the transport rate of assimilates into grains were accelerated, resulting in higher grain weight, yield, and water use efficiency(WUE). However, under SWD treatment, exogenous ABA improved the ratio of SA/ABA, leading to low Pro content and low antioxidant enzyme activity of flag leaves in the rapid loss phase. Meanwhile,drought resistance declined and the transport duration of assimilates into grains was shortened, thus making photosynthetic assimilates redundant. Therefore, exogenous ABA can lead to the reduction in grain weight, yield, and WUE of wheat under SWD treatment. | Yongli Luo Wenqian Li Cui Huang Junhao Yang Min Jin Jin Chen Dangwei Pang Yonglan Chang Yong Li Zhenlin Wang | 2021 | The Crop Journal2021，9，4： | 4 |
| 3 | Dynamic memory paravirtualization transparent to guest OS显示文摘This paper introduces dynamic paravirtualization, which imitates paravirtualization and aims at reducing VM exits of full virtualization with hardware support. In dynamic paravirtualization, VMM (virtual machine monitor) dynamically monitors and replaces the hot instructions, which cause most VM exits. It is transparent to the guest OS such that the legacy OSes can benefit from this optimization. Our study focuses on reducing the overhead of memory virtualization-dynamic memory paravirtualization (DMP). We implant a new memory management mechanism in VMM such that all user-mode page faults can be handled by the guest OS directly without VM exits. We implement a prototype of dynamic memory paravirtulization based on a version of KVM using Intel VT. Our experimental results show that our technique essentially eliminates the overhead of VM exits caused by page faults. Dynamic memory paravirtualization can achieve the effectiveness of paravirtualization without changing the source code of guest OS. | WANG XiaoLin SUN YiFeng LUO YingWei WANG ZhenLin LI Yu ZHANG BinBin CHEN HaoGang LI XiaoMing | 2010 | Science China(Information Sciences)2010，53，1： | 4 |
| 4 | Effects of exogenous ABA application on post-anthesis dry matter redistribution and grain starch accumulation of winter wheat with different staygreen characteristics显示文摘The objective of this study was to investigate whether and how exogenous abscisic acid(ABA)is involved in mediating starch accumulation in the grain and redistribution of carbohydrates during grain filling of two wheat cultivars with different staygreen characteristics.At blooming stage,plants of Wennong 6(a staygreen cultivar)and Jimai 20(control)were sprayed with10 mg L-1abscisic acid(ABA)for 3 days.The application of ABA significantly(P<0.05)increased grain filling rate,starch accumulation rate and content,remobilization of dry matters to kernels,and 1000-grain weight of the two cultivars.Exogenous ABA markedly(P<0.05)increased grain yield at maturity,and Wennong 6 and Jiami 20 showed 14.14%and 4.86%higher compared yield than the control.Dry matter accumulation after anthesis of Wennong 6 was also significantly(P<0.05)influenced by exogenous ABA,whereas that of Jimai 20 was unchanged.Application of ABA increased endogenous zeatin riboside(ZR)content 7 days after anthesis(DAA),and spraying ABA significantly increased endogenous indole-3-acetic acid(IAA)and ABA contents from 7 to 21 DAA and decreased gibberellin(GA3)content at 14 DAA,but increased GA3content from 21 to 35 DAA.The results suggested that increased yield of staygreen was due to greater starch assimilation owing to a higher filling rate and longer grain-filling duration. | Dongqing Yang Yongli Luo Yingli Ni Yanping Yin Weibing Yang Dianliang Peng Zhengyong Cui Zhenlin Wang | 2014 | The Crop Journal2014，2，Z1： | 3 |
| 5 | Interactions between cytokinin and nitrogen contribute to grain mass in wheat cultivars by regulating the flag leaf senescence process显示文摘Premature senescence after anthesis reduces crop yields.Delaying leaf senescence could maintain photosynthetic activity for a longer period and lead to a higher photosynthetic rate.Recent studies have provided some insights into the interaction between cytokinin and nitrogen(N)in the regulation of plant development.In the present study,foliar application of exogenous 6-benzylaminopurine(6-BA)and lovastatin,an inhibitor of cytokinin synthesis,was combined with three N rates[0 kg ha^(-1)(low nitrogen,LN),240 kg ha^(-1)(normal nitrogen,NN),and 360 kg ha^(-1)(high nitrogen,HN)]in two wheat cultivars,Wennong 6(with a staygreen phenotype)and Jimai 20(with a non-staygreen phenotype).Flag leaf senescence was assessed using a Gompertz growth curve.Grain mass,dry matter accumulation and distribution,total N of flag leaf,and concentrations of zeatin riboside(ZR)and abscisic acid(ABA)were also used to evaluate the functional characteristics of flag leaves.Grain mass was negatively correlated with initial senescence rate(r_0)and duration of rapid chlorophyll loss(Chl_(loss)),whereas it was positively correlated with maximum senescence rate(r_(max)),average senescence rate(r_(aver)),persistence phase(Chl_(per)),total duration of flag leaf(Chl_(total))and inflection point cumulative temperature(M).Compared to Jimai 20,Wennong 6 had larger r_(aver),Chl_(per),and Chl_(total).The concentration of ZR was highest under the 6-BA×NN treatment,followed by the 6-BA×HN and 6-BA×LN treatments.However,the concentration of ABA showed the opposite trend.It was concluded that the staygreen phenotype Wennong 6 was associated with greater grain mass and altered cytokinin metabolism and could be classified as a functional staygreen type.Foliar application of 6-BA interacting with N at the NN level(240 kg ha^(-1))may be a beneficial strategy for improving grain yield of wheat by regulating endogenous hormones and the flag leaf senescence process.Increasing endogenous cytokinin promoted the transport of dry matter to grain. | Yongli Luo Yuhai Tang Xin Zhang Wenqian Li Yonglan Chang Dangwei Pang Xu Xu Yong Li Zhenlin Wang | 2018 | The Crop Journal2018，6，5： | 2 |
| 6 | Dynamic cache partitioning based on hot page migration显示文摘静态的缓存划分能减少内部申请的缓存干扰并且当他们在在一样的多核心处理器分享最后水平缓存的核心上运行时,改进一个弄脏缓存的应用程序和一个缓存敏感的应用程序的合成性能。在一个虚拟化的系统,自从不同应用程序可能在不同时间在不同虚拟机(VM ) 上运行,预先静态地划分缓存是不适用的。这份报纸建议划分使用热页察觉和页移植根据缓存敏感的应用程序的优先的知识动态地改进共同招待的虚拟机的合成表演的计划的动态缓存。,试验性的结果在大多数情况中证明我们的页移植计划的开销是低的,合成性能是在免费作文上的改进。 | Xiaolin WANG Xiang WEN Yechen LI Zhenlin WANG Yingwei LUO Xiaoming LI | 2012 | Frontiers of Computer Science2012，6，4： | 2 |
| 7 | Synthesis of CaIn2O4 Rods and Its Photocatalytic Performance Under Visible-light Irradiation显示文摘 | Jianjun Ding Song Sun Jun Bao Zhenlin Luo Chen Gao | 2009 | Catalysis Letters (-)2009，，1： | 1 |
| 8 | Updated Understanding of Climate Change Sciences显示文摘 | Qin Dahe Chen Zhenlin Luo Yong | 2007 | Adv Clim Change Res2007，3，2： | 1 |
| 9 | Applications of combinatorial approach to the investigation of optical functional materials显示文摘Recent applications of combinatorial methodology to the investigation of optical functional materials are reviewed on the basis of the authors' work. The content includes: basic concepts of combinatorial materials science, combinatorial investigations of UV/VUV excited photoluminescence, luminescent rear earth complex doped polymer and magneto-optical materials. The fundamental synthesis tech-niques and characterization methods in combinatorial methodology are also illustrated in the text. | LUO ZhenLin BAO Jun DING JianJun CHEN Lei LI XueFei JIU HongFang ZHANG QiJin CHAN TingShan LIU RuXi GAO Chen | 2009 | Chinese Science Bulletin2009，54，11： | 0 |
| 10 | Evaluating the impacts of hugepage on virtual machines显示文摘Modern applications often require a large amount of memory. Conventional 4KB pages lead to large page tables and thus exert high pressure on TLB address translations. This pressure is more prominent in a virtualized system, which adds an additional layer of address translation. Page walks due to TLB misses can result in a significant performance overhead. One effort in reducing this overhead is to use hugepage. Linux kernel has supported transparent hugepage since 2.6.38, which provides an alternate large page size. Generally,hugepage demonstrates better performance on address translations and page table modifications. This paper first analyzes the impact of hugepage on native system, and then, compares the impact of hugepage on different memory virtualization approaches: hardware-assisted paging(HAP), shadow paging, and para-virtualization.We observe that the current implementation of transparent hugepage is inefficient. It cannot exploit the full performance advantage of hugepages. Worse yet, the conservative strategy of transparent hugepage may conflict with existing OS functions, which can lead to performance degradation. So, we propose a new memory allocation strategy, alignment-based hugepage(ABH) that promotes hugepage allocations. We apply ABH to different paging modes in virtualized systems. The results show that the new allocation strategy can significantly reduce TLB misses and up to 90% page walk cycles due to TLB misses and thus improve the performance in real world applications. | Xiaolin WANG Taowei LUO Jingyuan HU Zhenlin WANG Yingwei LUO | 2017 | Science China(Information Sciences)2017，60，1： | 0 |
| 11 | Huge Page Friendly Virtualized Memory Management显示文摘With the rapid increase of memory consumption by applications running on cloud data centers,we need more efficient memory management in a virtualized environment.Exploiting huge pages becomes more critical for a virtual machine's performance when it runs large working set size programs.Programs with large working set sizes are more sensitive to memory allocation,which requires us to quickly adjust the virtual machine's memory to accommodate memory phase changes.It would be much more efficient if we could adjust virtual machines'memory at the granularity of huge pages.However,existing virtual machine memory reallocation techniques,such as ballooning,do not support huge pages.In addition,in order to drive effective memory reallocation,we need to predict the actual memory demand of a virtual machine.We find that traditional memory demand estimation methods designed for regular pages cannot be simply ported to a system adopting huge pages.How to adjust the memory of virtual machines timely and effectively according to the periodic change of memory demand is another challenge we face.This paper proposes a dynamic huge page based memory balancing system(HPMBS)for efficient memory management in a virtualized environment.We first rebuild the ballooning mechanism in order to dispatch memory in the granularity of huge pages.We then design and implement a huge page working set size estimation mechanism which can accurately estimate a virtual machine's memory demand in huge pages environments.Combining these two mechanisms,we finally use an algorithm based on dynamic programming to achieve dynamic memory balancing.Experiments show that our system saves memory and improves overall system performance with low overhead. | Sai Sha Jing-Yuan Hu Ying-Wei Luo Xiao-Lin Wang Zhenlin Wang | 2020 | Journal of Computer Science & Technology2020，35，2： | 0 |
| 12 | The H3K9me2-binding protein AGDP3 limits DNA methylation and transcriptional gene silencing in Arabidopsis显示文摘DNA methylation,a conserved epigenetic mark,is critical for tuning temporal and spatial gene expression.The Arabidopsis thaliana DNA glycosylase/lyase REPRESSOR OF SILENCING 1(ROS1)initiates active DNA demethylation and is required to prevent DNA hypermethylation at thousands of genomic loci.However,how ROS1 is recruited to specific loci is not well understood.Here,we report the discovery of Arabidopsis AGENET Domain Containing Protein 3(AGDP3)as a cellular factor that is required to prevent gene silencing and DNA hypermethylation.AGDP3 binds to H3K9me2 marks in its target DNA via its AGD12 cassette.Analysis of the crystal structure of the AGD12 cassette of AGDP3 in complex with an H3K9me2 peptide revealed that dimethylated H3 K9 and unmodified H3 K4 are specifically anchored into two different surface pockets.A histidine residue located in the methyllysine binding aromatic cage provides AGDP3 with pH-dependent H3K9me2 binding capacity.Our results uncover a molecular mechanism for the regulation of DNA demethylation by the gene silencing mark H3K9me2. | Xuelin Zhou Mengwei Wei Wenfeng Nie Yue Xi Li Peng Qijie Zheng Kai Tang Viswanathan Satheesh Yuhua Wang Jinyan Luo Xuan Du Rui Liu Zhenlin Yang Honggui La Yingli Zhong Yu Yang Jian-Kang Zhu Jiamu Du Mingguang Lei | 2022 | Journal of Integrative Plant Biology2022，64，12： | 0 |
| 13 | Investigations of structural phase transformation and THz properties across metal–insulator transition in VO_2/Al_2O_3epitaxial films显示文摘Vanadium dioxide(VO2) epitaxial thin films on(0001)-oriented Al2O3 substrates were prepared using radio frequency(RF) magnetron sputtering techniques.To study the metal-insulator-transition(MIT) mechanism and extend the applications of VO2 epitaxial films at terahertz(THz) band,temperature-dependent X-ray diffraction(XRD) and THz time domain spectroscopy of the VO2 epitaxial films were performed.Both the lattice constants and THz transmission exhibited a similar and sharp transition that was similar to that observed for the electrical resistance.Consequently,the MIT of the VO2/Al2O3 epitaxial films should be co-triggered by the structural phase transition and electronic transition.Moreover,the very large resistance change(on the order of 103) and THz response(with a transmission modulation ratio of 87%) in the VO2/Al2O3 epitaxial heterostructures are promising for electrical switch and electro-optical device applications. | Mengmeng Yang Yuanjun Yang Bin Hong Yi Zhao Xiaoguang Li Yalin Lu Zhenlin Luo Chen Gao | 2015 | Progress in Natural Science:Materials International2015，25，5： | 0 |
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