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Science China(Life Sciences) 2020年第1期63卷 148-151页

作者： Qingfeng Liang Leying Wang xuyang liu Beijing Institute of Ophthalmology Beijing Tongren Eye CenterBeijing Tongren HospitalCapital Medical UniversityBeijing Key Laboratory of Ophthalmology and Visual SciencesBeijing 100005China Xiamen Eye Center Xiamen UniversityXiamen 361011China Department of Ophthalmology Shenzhen Ophthalmology HospitalShenzhen 518040China

Glaucoma is the second leading cause of blindness after cataract ***,among irreversible blinding eye diseases,glaucoma is the primary cause(Liang et al.,2011).To date,most studies have indicated that glaucoma is not only an ocular disease,but also an optic nerve *** particular,primary open-angle glaucoma(POAG)is characterized by insidious onset,painless visual impairment,and complicated pathological mechanism,and patients with such condition require long-term ***,the underlying cause of POAG remains unclear,and there are several theories about its exact *** mechanisms have presented underlying optic nerve damage,which include the mechanical theory,vascular theory,and the in・volvement of other factors.

关键词： glaucoma al. cataract

Multi-Clock Snapshot Isolation Concurrency Control for NVM Database

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Tsinghua Science and Technology 2022年第6期27卷 925-938页

作者： xuyang liu Kang Chen Mengxing liu Shiyu Cai Yongwei Wu Weimin Zheng Department of Computer Science and Technology Tsinghua UniversityBeijing 100084China

Multi-Clock Snapshot Isolation(MCSI)is a concurrency control mechanism that implements snapshot isolation on a single-layer Non-Volatile Memory(NVM)*** stores a single copy of data by using multi-version storage to ensure durability and runtime *** multi-clock transaction timestamp assignment,MCSI can efficiently generate snapshots with vector clocks and use per-thread transaction status arrays to identify uncommitted versions in *** evaluation,we compared MCSI with the PostgreSQL-style concurrency control used in the single-layer NVM database *** maximum transaction throughput of MCSI is 101%–195%higher than that of N2DB for the YCSB workloads,and 25%–49%higher for the TPC-C ***,the transaction latency of MCSI remains relatively stable as the thread count *** 18 worker threads,the average transaction latency of MCSI is 65%–84%lower than that of N2DB for the YCSB workloads and 16%–43%lower for the TPC-C workloads.

关键词： Non-Volatile Memory(NVM) snapshot isolation Multi-Version Concurrency Control(MVCC) vector clock

Homogeneous precipitation of α-phase Co-Ni hydroxides hexagonal platelets

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Particuology 2012年第1期10卷 24-28页

作者： Juanjuan liu xuyang Wang Xiayin Yao Jun wang Zhaoping liu Ningbo Institute of Material Technology ＆ Engineering Chinese Academy of Sciences Ningbo 315201 China

This paper describes the synthesis of （x-phase Co-Ni hydroxides hexagonal platelets through homo- geneous precipitation, using hexamethylenetetramine （HMT） or urea as a hydrolytic agent. In the CoC12-NiC12-HMT system, pure β-phase can be synthesized at the concentrations of both metal ions higher than 20 raM, while in the CoCl2-NiCl2-urea system, the formation of pure α-phase is independent of the concentrations of the metal ions. When using HMT, monodisperse hexagonal platelets of α-phase Co-Ni hydroxides can be produced in the presence of polyvinylpyrrolidone （PVP）. Cyclic voltammogram curve of the hexagonal platelets prepared with HMT demonstrates electrochemical performance superior to that of urea.

关键词： Homogeneous precipitation α-PhaseHydrolysisHexagonal plateletsCyclic voltammogram

Garbage Collection and Data Recovery for N2DB

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Tsinghua Science and Technology 2022年第3期27卷 630-641页

作者： Shiyu Cai Kang Chen Mengxing liu xuyang liu Yongwei Wu Weimin Zheng Department of Computer Science and Technology Tsinghua UniversityBejing 100084China

Non-Volatile Memory(NVM) offers byte-addressability and persistency. Because NVM can be plugged into memory and provide low latency, it offers a new opportunity to build new database systems with a single-layer storage design. A single-layer NVM-Native DataBase(N2 DB) provides zero copy and log freedom. Hence, all data are stored in NVM and there is no extra data duplication and logging during execution. N2 DB avoids complex data synchronization and logging overhead in the two-layer storage design of disk-oriented databases and in-memory databases. Garbage Collection(GC) is critical in such an NVM-based database because memory leaks on NVM are durable. Moreover, data recovery is equally essential to guarantee atomicity, consistency, isolation, and durability properties. Without logging, it is a great challenge for N2 DB to restore data to a consistent state after crashes and recoveries. This paper presents the GC and data recovery mechanisms for N2 DB. Evaluations show that the overall performance of N2 DB is up to 3:6 higher than that of InnoDB. Enabling GC reduces performance by up to 10%,but saves storage space by up to 67%. Moreover, our data recovery requires only 0:2% of the time and half of the storage space of InnoDB.

关键词： Non-Volatile Memory(NVM) Garbage Collection(GC) data recovery

Theoretical expressions for soil particle detachment rate due to saltation bombardment in wind erosion

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Research in Cold and Arid Regions 2020年第4期12卷 234-241页

作者： xuyang liu WenXiao Ning ZhenTing Wang Key Laboratory of Desert and Desertification Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhouGansu 730000China University of Chinese Academy of Sciences Beijing 100049China

Saltation bombardment is a dominate dust emission mechanism in wind *** loose surfaces,splash entrainment has been well understood ***,the mass loss predictions of cohesive soils are generally empirical in most wind erosion *** this study,the soil particle detachment of a bare,smooth,dry,and uncrusted soil surface caused by saltation bombardment is modeled by means of classical *** is shown that detachment rate can be analytically expressed in terms of the kinetic energy or mass flux of saltating grains and several common mechanical parameters of soils,including Poisson's ratio,Young's modulus,cohesion and friction *** novel expressions can describe dust emission rate from cohesive surfaces and are helpful to quantify the anti-erodibility of *** is proposed that the mechanical properties of soils should be appropriately included in physically-based wind erosion models.

关键词： wind erosion saltation bombardment cohesive soil anti-erodibility

GOLDEN 2-LIKE transcription factors regulate chlorophyll biosynthesis and flavonoid accumulation in response to UV-B in tea plants

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Horticultural Plant Journal 2023年第5期9卷 1055-1066页

作者： xuyang liu Xin Cheng Jingjie Cao Wenfeng Zhu Xiaochun Wan Linlin liu State Key Laboratory of Tea Plant Biology and Utilization Key Laboratory of Tea Biology and Tea Processing of Ministry of AgricultureAnhui Provincial Laboratory of Tea Plant Biology and UtilizationAnhui Agricultural UniversityHefeiAnhui 230036China

Flavonoids are critical secondary metabolites that determine the health benefits and flavor of tea,while chlorophylls are important contributors to the appearance of ***,transcription factors(TFs)that can integrate both chlorophyll biosynthesis and flavonoid accumulation in response to specific light signals are rarely *** this study,we report that the GOLDEN 2-LIKE TF pair,CsGLK1 and CsGLK2,orchestrate UV-B-induced responses in the chlorophyll biosynthesis and flavonoid accumulation of tea *** absence of solar UV-B reduced the transcriptional expression of CsGLKs in the tea leaves and was highly correlated with a decrease in flavonoid levels(especially flavonol glycosides)and the expression of genes and TFs involved in chlorophyll biosynthesis and flavonoid *** vivo and in vitro molecular analyses showed that CsGLKs could be regulated by the UV-B signal mediator CsHY5,and could directly bind to the promoters of gene and TF involved in light-harvesting(CsLhcb),chlorophyll biosynthesis(CsCHLH,CsHEMA1,and CsPORA),and flavonoid accumulation(CsMYB12,CsFLSa,CsDFRa,and CsLARa),eventually leading to UV-B-induced responses in the chlorophylls and flavonoids of tea ***,UV-B exposure increased the levels of total flavonoids,CsGLK1 protein,and expression of CsGLKs and target genes in the tea *** results indicate that CsGLKs may modulate tea leaf characteristics by regulating chlorophyll biosynthesis and flavonoid accumulation in response to solar *** the first report on UV-B-induced changes in flavonoid and chlorophyll regulation mediated by CsGLKs,this study improves our understanding of the environmental regulations regarding tea quality and sheds new light on UV-B-induced flavonoid responses in higher plants.

关键词： Camellia sinensis GLK Flavonoid Chlorophyll UV-B

A survey of geothermal power generation combined with renewable energy for low carbon emissions

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Clean Energy 2024年第3期8卷 138-146页

作者： xuyang liu Dongsheng Cai Chiagoziem CUkwuoma Qi Huang Olusola Bamisile College of Nuclear Technology and Automation Engineering Chengdu University of TechnologyChengduSichuan P.R.China Electrical Engineering Department Southwest University of Science and TechnologyMaiyangSichuan P.R.China

At present,industrial development is heavily dependent on traditional fossil energy,which has had an increasingly serious impact on the *** and renewable energy has received extensive attention and its proportion in daily life has gradually *** a clean and renewable energy source that is not affected by changes in weather and seasons,geothermal energy has developed rapidly in recent years and has received increasing *** to reports,the total installed capacity of geothermal power generation in the world in 2020 was 15950 MW-an increase of~27%over *** the end of 2019,the total installed capacity for global geothermal direct use was 107727 MW-an increase of 52.0%compared with 2015;the total annual energy use was 1020887 TJ(283580 GWh)-an increase of 72.3%over *** the investigation of geothermal power generation technology in recent years,the characteristics and shortcomings of various power generation methods are *** the same time,this review analyzes the characteristics of geothermal energy and other renewable-energy(solar energy,water energy)coupling power generation,and analyzes the principles and characteristics of geothermal energy and various new-energy coupling power generation *** investigation and analysis,this review provides a complete understanding of various geothermal power generation technologies and provides insights into the future development direction.

关键词： geothermal power generation solar energy water energy combined power generation

Newly Discovered Fluvial-Lacustrine Sediments in the Western Yangtze Block and their Geological Significance for the Emeishan Large Igneous Province

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Acta Geologica Sinica(English Edition) 2017年第2期91卷 741-742页

作者： MABI Awei ZHANG Mingchun YANG Zhengxi LI Yanlong WEN Dengkui liu xuyang School of Earth Sciences Chengdu University of TechnologyChengdu 610059SichuanChina Meigu Bureau of Land and Resources Meigu 616450SichuanChina Panxi Team Sichuan Bureau of Geology and Mineral ResourcesXichang 615000SichuanChina Department of Geological Sciences The University of Texas at E1 PasoEI Paso 79968TexasUSA

Objective The Emeishan large igneous province （ELIP） in SW China is the only one large igneous province in China recognized by international geologists. Previous studies of ELIP over past two decades indicate that the ELIP age, duration, scale and generation mechanism are still controversial. Among those scientific topics, some scholars suggest that ELIP is an example of up-doming prior to LIP formation, which was evidenced by：（1） The thickness of the Yangxin Formation （P^v） limestone unit, which lies directly beneath ELIP, reduces from the center of erosional area to the outer edge. （2） Paleo-karst surfaces are present. （3） The clastic rocks of alluvial fan deposits, from the eroded materials in the maximum uplifted area, developed surrounding the inner zone. However, other scholars urge that those so-called ＂alluvial fan＂ deposits are ＂hydromagmatic deposits＂, erupted or emplaced at or near sea level, and conclude that there was no pre-emptive uplift in ELIP. In order to constrain the above-mentioned scientific issue, we conducted detailed field geological investigations and systematically measured geological sections to provide new evidence by using sedimentary data.

关键词： Newly Discovered Fluvial-Lacustrine Sediments in the Western Yangtze Block and their Geological Significance for the Emeishan Large Igneous Province

Two Types of Granites in the Western Yangtze Block and Their Implications for Regional Tectonic Evolution： Constraints from Geochemistry and Isotopic Data

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Acta Geologica Sinica(English Edition) 2018年第1期92卷 89-105页

作者： MABI Awei YANG Zhengxi ZHANG Mingchun WEN Dengkui LI Yanlong liu xuyang School of Earth Sciences Chengdu University of Technology Chengdu 610059 Sichuan China Panxi Team Sichuan Bureau of Geology and Mineral Resources Xiehang 615000 Sichuan China Department of Geological Sciences The University of Texas at E1 Paso E1 Paso 79968 Texas USA

In the western Yangtze Block, widespread Mesoproterozoic to Neoproterozoic rocks are the key to understanding the Precambrian tectonic-magmatic evolution of the region. However, their petrogenesis and tectonic setting are still controversial. In this paper, zircon U-Pb ages, Sm-Nd isotopic and whole-rock geochemical data are reported from selected fresh samples in the southern Dechang county, southwestern China, in order to constrain their emplacement age and magma source, as well as their petrogenesis and tectonic setting. They are mainly composed of biotite monzogranite, monzonitic granite, biotite granodiorites, and quartz diorite. Two ages of 1055 ± 43 Ma and 837.6 ± 3.8 Ma were obtained through zircon U-Pb dating by LA-ICP-MS and LA-MC-ICP-MS, respectively. According to their major element compositions, the Grenville-age granites are peraluminous calc-alkaline series calcic S-type granite. In contrast, the mid-Neoproterozoic granites are metaluminous calc-aikaline series alkalic I-type granite. Furthermore, the S-type granites are enriched in LREEs relative to HREEs with （La/Yb）N ratios of 3.85-18.56 and underwent major fractionation with strongly negative Eu anomalies （Eu/Eu＊ = 0.38-0.66）. In the MORB-normalized trace element variation diagram, all the samples are enriched in Ce and large ion lithophile elements such as Rb, Th, and K, and depleted in high field strength elements such as Nb, and Ti, with negative Sr and Ti anomalies. The I-type granites are enriched in LREEs with slight negative Eu anomalies （Eu/Eu＊= 0.83-0.93）. They are characterized by the enrichment of highly incompatible elements （such as K, Rb, Ba, Th） and LREEs, relative to MORB. Neodymium isotopic data show that the S-type granites display 143Nd/144Nd values of 0.51241-0.51256, and have eNa （t = 1055 Ma） values of （-3.29） to （-3.81）. Calculated tDM ages yield values from 1.87 to 1.91 Ga with the tDM.2stg ages of 1.86 to 1.9 Ga. The I-type granites have 143Nd/144Nd ratios between 0.51192

关键词： 1-type granite S-type granite geochemistry petrogenesis tectonic setting Western YangtzeBlock

Shading effects revisited:Comparisons of spring and autumn shading treatments reveal a seasonal-dependent regulation on amino acids in tea leaves

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Beverage Plant Research 2023年第1期3卷 42-50页

作者： Wenfeng Zhu xuyang liu Xin Cheng Yingying Li Linlin liu State Key Laboratory of Tea Plant Biology and Utilization Anhui Agricultural UniversityWest 130 Changjiang RoadHefei 230036AnhuiChina

Shading is an effective way to improve tea quality by modulating the accumulation of the flavor-related secondary metabolites of tea ***,shading effects on amino acids have been conflicting for years as both shading-induced increases and decreases have been *** study aims to investigate the effects of shading levels on catechins and amino acids,in particular,a comparison was made in April and August to better understand the involvement of seasonal environmental *** reduced major catechins(catechin,gallocatechin,epicatechin,epigallocatechin,epicatechin gallate,and epigallocatechin gallate)in both *** shading(80%−90%)increased total and individual amino acids(threonine,glutamic acid,and alanine)in April but decreased those in *** both seasons,ᴏ-Phosphoethanolamine increased under heavy shading,butα-aminoadipic acid,ornithine and glutamine showed *** showed no shading response in April but decreased under heavy shading in *** results indicate that shading-induced reduction of leaf catechins is mainly determined by shading level,but the shading effects on amino acids are *** our first report focuses on the synergistic effects of seasons,this study improves our understanding of shading regulation on secondary metabolites of tea leaves and guides shading treatments to improve tea quality.

关键词： parameters. synergistic seasonal