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GOLDEN 2-LIKE transcription factors regulate chlorophyll biosynthesis and flavonoid accumulation in response to UV-B in tea plants 被引量:2
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作者 xuyang liu Xin Cheng +3 位作者 Jingjie Cao Wenfeng Zhu Xiaochun Wan Linlin liu 《Horticultural Plant Journal》 SCIE CAS CSCD 2023年第5期1055-1066,共12页
Flavonoids are critical secondary metabolites that determine the health benefits and flavor of tea,while chlorophylls are important contributors to the appearance of tea.However,transcription factors(TFs)that can inte... Flavonoids are critical secondary metabolites that determine the health benefits and flavor of tea,while chlorophylls are important contributors to the appearance of tea.However,transcription factors(TFs)that can integrate both chlorophyll biosynthesis and flavonoid accumulation in response to specific light signals are rarely identified.In 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 leaves.The 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 accumulation.In 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 leaves.Furthermore,UV-B exposure increased the levels of total flavonoids,CsGLK1 protein,and expression of CsGLKs and target genes in the tea leaves.These results indicate that CsGLKs may modulate tea leaf characteristics by regulating chlorophyll biosynthesis and flavonoid accumulation in response to solar UV-B.As 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. 展开更多
关键词 Camellia sinensis GLK Flavonoid CHLOROPHYLL UV-B
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The classification of plants by laser-induced breakdown spectroscopy based on two chemometric methods 被引量:2
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作者 冯中琦 张大成 +3 位作者 王博文 丁捷 刘旭阳 朱江峰 《Plasma Science and Technology》 SCIE EI CAS CSCD 2020年第7期92-97,共6页
The applications of laser-induced breakdown spectroscopy(LIBS) on classifying complex natural organics are relatively limited and their accuracy still requires improvement.In this work,to study the methods on classifi... The applications of laser-induced breakdown spectroscopy(LIBS) on classifying complex natural organics are relatively limited and their accuracy still requires improvement.In this work,to study the methods on classification of complex organics,three kinds of fresh leaves were measured by LIBS.100 spectra from 100 samples of each kind of leaves were measured and then they were divided into a training set and a test set in a ratio of 7:3.Two algorithms of chemometric methods including the partial least squares discriminant analysis(PLS-DA) and principal component analysis Mahalanobis distance(PCA-MD) were used to identify these leaves.By using 23 lines from 16 elements or molecules as input data,these two methods can both classify these three kinds of leaves successfully.The classification accuracies of training sets are both up to 100% by PCA-MD and PLS-DA.The classification accuracies of the test set are 93.3% by PCA-MD and 97.8% by PLS-DA.It means that PLS-DA is better than PCA-MD in classifying plant leaves.Because the components in PLS-DA process are more suitable for classification than those in PCA-MD process.We think that this work can provide a reference for plant traceability using LIBS. 展开更多
关键词 laser-induced breakdown spectroscopy principal component analysis Mahalanobis distance partial least squares discriminant analysis classification of complex organics
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Theoretical expressions for soil particle detachment rate due to saltation bombardment in wind erosion 被引量:1
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作者 xuyang liu WenXiao Ning ZhenTing Wang 《Research in Cold and Arid Regions》 CSCD 2020年第4期234-241,共8页
Saltation bombardment is a dominate dust emission mechanism in wind erosion.For loose surfaces,splash entrainment has been well understood theoretically.However,the mass loss predictions of cohesive soils are generall... Saltation bombardment is a dominate dust emission mechanism in wind erosion.For loose surfaces,splash entrainment has been well understood theoretically.However,the mass loss predictions of cohesive soils are generally empirical in most wind erosion models.In 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 mechanics.It 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 angle.The novel expressions can describe dust emission rate from cohesive surfaces and are helpful to quantify the anti-erodibility of soil.It is proposed that the mechanical properties of soils should be appropriately included in physically-based wind erosion models. 展开更多
关键词 wind erosion saltation bombardment cohesive soil anti-erodibility
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The effects of circadian rhythm on catechin accumulation in tea leaves 被引量:2
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作者 Xiaohui Wang Wenfeng Zhu +5 位作者 Xin Cheng Zhiqiang Lu xuyang liu Xiaochun Wan Chuankui Song Linlin liu 《Beverage Plant Research》 2021年第1期60-68,共9页
As the major bitter-and astringent-tasting components in tea leaves,catechins play an essential role in determining flavor characteristics and health benefits of tea products.This study analyzed the circadian rhythm e... As the major bitter-and astringent-tasting components in tea leaves,catechins play an essential role in determining flavor characteristics and health benefits of tea products.This study analyzed the circadian rhythm effects on the accumulation pattern of catechins in tender leaves of three tea cultivars,'Huangkui'(HK),'Longjing43'(LJ43)and'Fuding Dabaicha'(FD).There were two major factors involved in the catechin regulation in tea plants:genetic background of the cultivar-specific regulation,and temporal effects of the circadian rhythm.Etiolated leaves of'HK'contained lower levels of catechins than'LJ43'and'FD'.The composition of EGCG in total catechins was significantly higher in'LJ43'leaves(65%)when compared with that in'HK'and'FD'(45%).The accumulation of individual catechins increased during the daytime but decreased overnight,especially over the time period of 22:00−02:00.The correlation analysis between catechins and environmental factors indicated catechin accumulation in tea leaves potentially resulted from a combined regulation of light and temperature.These findings provide new insights into our understanding of circadian rhythm regulation on flavor-important secondary metabolites in tea leaves. 展开更多
关键词 LEAVES CIRCADIAN CATECHIN
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Carbamylation of Human Lens γ-crystaUins:Relevance to Cataract Formation
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作者 xuyang liu Shaozhen Li 《眼科学报》 1993年第3期136-142,157,共8页
Cigarette smoking is a main source of cyanide in human body,which can be taken as a risk factor of cataract formation.In this study,combined gas chromatography and mass spectrum(GC/MS)was used todetermine the amino ac... Cigarette smoking is a main source of cyanide in human body,which can be taken as a risk factor of cataract formation.In this study,combined gas chromatography and mass spectrum(GC/MS)was used todetermine the amino acid hydantoin after the incubation of soluble humanlensγ-crystallins with cyanate.The carbamylated amino acids obtained bythis procedure are alanine and hlycine,which are N-terminal amino acids ofγ-crystallin,and leucine.The aggregate,which can be observed incarbamylatedγ_1-crystallin on SDS-PAGE,may be related to the formation of disulfide and non-disulfide covalent bonds,and it seems that Y₂and Yy-crystallins can not be aggregated to any great extend.The results in this study indicate that the GC/MS is an effective method for analyzing the carbamylation of lens proteins;y-crystallin may play a very important role in the formation of cataract associated with accumulation of cyanate in human body,such as heavy smoking. 展开更多
关键词 CARBAMYLATION HYDANTOIN GC/MS Iens crystallin smokjng CATARACT
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Expression of Med 19 Protein in Tongue Cancer and Its Significance
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作者 xuyang liu Lingling LI Shengzhi WANG 《Medicinal Plant》 2017年第2期54-56,共3页
[Objectives] To study the expression of Med 19 protein in tongue cancer and its significance. [Methods] Immunohistochemical method was used to detect the expression of Med 19 protein in tongue cancer tissue and paraca... [Objectives] To study the expression of Med 19 protein in tongue cancer and its significance. [Methods] Immunohistochemical method was used to detect the expression of Med 19 protein in tongue cancer tissue and paracancerous tissue. [Results]The expression of Med19 protein in tongue cancer tissue was higher than paracancerous tissue and normal tissue. The expression of Med 19 protein was related to the tumor lymph node metastasis. However,there was no significant difference in sex,age,Tumor Node Metastasis( TNM),and differentiation degree. [Conclusions] Med 19 protein participates in incidence and development of tongue cancer and may become diagnostic indicator and therapeutic target for tongue cancer. 展开更多
关键词 MED 19 PROTEIN TONGUE CANCER IMMUNOHISTOCHEMISTRY
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近视合并原发性闭角型青光眼的眼前节参数特征 被引量:3
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作者 张瑶 史吟雯 +6 位作者 潘晓华 赵丽君 樊宁 邱敬华 毛禹凯 刘旭阳 唐莉 《中华眼视光学与视觉科学杂志》 CAS CSCD 2023年第2期111-116,共6页
目的:分析近视合并原发性闭角型青光眼(PACG)的眼前节参数特征及近视与PACG的关系。方法:多中心横断面研究。连续纳入2019年1月至2021年8月厦门大学附属眼科中心、四川大学华西医院眼科、深圳市眼科医院、大连市第三人民医院眼科、郑州... 目的:分析近视合并原发性闭角型青光眼(PACG)的眼前节参数特征及近视与PACG的关系。方法:多中心横断面研究。连续纳入2019年1月至2021年8月厦门大学附属眼科中心、四川大学华西医院眼科、深圳市眼科医院、大连市第三人民医院眼科、郑州市第二人民医院眼科等5个眼科中心明确诊断的近视合并PACG患者210例(263眼)。根据等效球镜度(SE)将受检眼分为低度近视组(SE-3.00~-1.00 D)、中度近视组(SE-6.00~-3.00 D)、高度近视组(SE≤-6.00 D)。根据眼轴长度(AL)将受检眼分为AL≤24 mm组和AL>24 mm组。所有患眼均接受常规眼科检查,采用主观验光仪进行屈光度检查,采用IOLMaster 700测定中央前房深度(ACD)、晶状体厚度(LT)、AL,根据公式计算SE、玻璃体腔长度(VL)、相对晶状体位置(RLP)。不同近视程度组间眼前节参数比较采用单因素方差分析,不同AL组间眼前节参数比较采用独立样本t检验。结果:低度近视组176眼,中度近视组60眼,高度近视组27眼,3组受检眼AL总体比较差异有统计学意义(F=27.95,P<0.001),其中高度近视组AL长于低度近视组和中度近视组,差异均有统计学意义(均P<0.001);3组间LT总体比较差异有统计学意义(F=5.81,P=0.003),其中高度近视组LT短于低度近视组和中度近视组(P=0.002、0.001);3组间RLP总体比较差异有统计学意义(F=13.69,P<0.001),其中高度近视组RLP比低度近视组和中度近视组更靠前(P<0.001)。AL>24 mm组受检眼ACD比AL≤24 mm组深(t=-2.60,P=0.010),但AL>24 mm组受检眼RLP比AL≤24 mm组更靠前(t=6.74,P<0.001)。结论:高度近视合并PACG的AL较长,LT较短,但RLP更靠前。相对拥挤的前房结构可能是此类近视患者发生房角关闭的原因之一。 展开更多
关键词 近视 原发性闭角型青光眼 眼前节参数
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氟化高浓电解液实现无水氟化铜正极的可逆循环
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作者 戴一铭 刘旭阳 +5 位作者 伍旺炎 黄瑛 王腾锐 宋振友 张任远 罗巍 《Science China Materials》 SCIE EI CAS CSCD 2023年第8期3039-3045,共7页
无水氟化铜(CuF_(2))有望成为下一代锂电池正极材料,其高比容量(528 mA h g^(−1))和高工作电压(3.55 V vs.Li/Li^(+))使得其能量密度高达1874 W h kg^(−1).然而,由于充电时铜的溶解,CuF_(2)正极容易失活,这限制了其发展.本研究采用氟化... 无水氟化铜(CuF_(2))有望成为下一代锂电池正极材料,其高比容量(528 mA h g^(−1))和高工作电压(3.55 V vs.Li/Li^(+))使得其能量密度高达1874 W h kg^(−1).然而,由于充电时铜的溶解,CuF_(2)正极容易失活,这限制了其发展.本研究采用氟化高浓电解液抑制铜的溶解,从而实现了CuF_(2)正极的可逆循环.采用氟化高浓电解液后,CuF_(2)正极的容量在30次循环后仍保有228 mA h g^(−1),是使用传统碳酸酯类电解液的电池容量的近三倍.综上,本研究提出了一种电解质工程策略,可以实现CuF_(2)正极的可逆充放电. 展开更多
关键词 锂电池正极材料 电池容量 可逆循环 电解液 高比容量 能量密度 工作电压 碳酸酯
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可解释深度学习在光谱和医学影像分析中的应用 被引量:1
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作者 刘煦阳 段潮舒 +1 位作者 蔡文生 邵学广 《化学进展》 SCIE CAS CSCD 北大核心 2022年第12期2561-2572,共12页
深度学习是一种基于神经网络的建模方法,通过不同功能感知层的构建获得优化模型,提取大量数据的内在规律,实现端到端的建模。数据规模的增长和计算能力的提高促进了深度学习在光谱及医学影像分析中的应用,但深度学习模型可解释性的不足... 深度学习是一种基于神经网络的建模方法,通过不同功能感知层的构建获得优化模型,提取大量数据的内在规律,实现端到端的建模。数据规模的增长和计算能力的提高促进了深度学习在光谱及医学影像分析中的应用,但深度学习模型可解释性的不足是阻碍其应用的关键因素。为克服深度学习可解释性的不足,研究者提出并发展了可解释性方法。根据解释原理的不同,可解释性方法划分为可视化方法、模型蒸馏及可解释模型,其中可视化方法及模型蒸馏属于外部解释算法,在不改变模型结构的前提下解释模型,而可解释模型旨在使模型结构可解释。本文从算法角度介绍了深度学习及三类可解释性方法的原理,综述了近三年深度学习及可解释性方法在光谱及医学影像分析中的应用。多数研究聚焦于可解释性方法的建立,通过外部算法揭示模型的预测机制并解释模型,但构建可解释模型方面的研究相对较少。此外,采用大量标记数据训练模型是目前的主流研究方式,但给数据的采集带来了巨大的负担。基于小规模数据的训练策略、增强模型可解释性的方法及可解释模型的构建仍是未来的发展趋势。 展开更多
关键词 深度学习 可解释性方法 神经网络 医学影像分析 光谱分析
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A writable lithium metal ink 被引量:4
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作者 Wangyan Wu Jian Duan +7 位作者 Jiayun Wen Yuwei Chen xuyang liu Liqiang Huang Zhengfeng Wang Shengyuan Deng Yunhui Huang Wei Luo 《Science China Chemistry》 SCIE EI CAS CSCD 2020年第10期1483-1489,共7页
The recent revival of Li metal anodes(LMA)leads to a renewed interest in LMA as the ultimate choice for rechargeable lithium batteries towards high energy density.However,multiple challenges stand in the way of using ... The recent revival of Li metal anodes(LMA)leads to a renewed interest in LMA as the ultimate choice for rechargeable lithium batteries towards high energy density.However,multiple challenges stand in the way of using LMA,of which high reactivity,dendrite growth,the difficulty of fabricating Li thin foils,and the flammability of organic liquid electrolytes are typical.Here,a writable Li metal ink(LMI)prepared by introducing biomass-derived carbon particles into molten Li is presented.Due to the significantly decreased surface tension,LMI is able to directly write on copper foils or other substrates that ultrathin Li foils with a remarkably small thickness(<10μm)can be achieved.The versatility of LMI is further demonstrated in addressing the interface issue between LMA and garnet-type solid-state electrolytes,where directly writing LMI on the garnet offers a perfect contact and enables an extremely low interfacial resistance of 6Ωcm^2,in sharp contrast to 939Ωcm^2 between the pure Li and the garnet.Due to the successful partnership with non-flammable solid-state electrolytes,ink-based technology may have a chance to bring us very close to the use of solid-state lithium metal batteries(SSLMBs)with high safety and high energy density. 展开更多
关键词 lithium metal ink surface tension solid-state batteries INTERFACE controllable thickness
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一种基于合成肽段涂层的单细胞蛋白质组学快速检测方法 被引量:2
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作者 李思奇 苏恺婵 +11 位作者 庄镇堃 秦晴 高磊 邓亚美 刘旭阳 侯桂雪 王龙涛 郝丕良 杨焕明 刘斯奇 朱鸿明 任艳 《Science Bulletin》 SCIE EI CSCD 2022年第6期581-584,M0003,共5页
单细胞层面的蛋白质组学研究极具挑战.本文报道了一种简单、快速的单细胞蛋白质组学方法(Mad-CASP),创新地设计了一套质谱兼容的合成肽段:(1)样品制备过程中,合成肽段的包被可以有效地减少样品损失;(2)质谱数据采集时,合成肽段的信号被... 单细胞层面的蛋白质组学研究极具挑战.本文报道了一种简单、快速的单细胞蛋白质组学方法(Mad-CASP),创新地设计了一套质谱兼容的合成肽段:(1)样品制备过程中,合成肽段的包被可以有效地减少样品损失;(2)质谱数据采集时,合成肽段的信号被摒除,对样品信号无影响;(3)全流程无需特殊设备,可在3~4小时内完成96孔样品的高通量制备.结合图谱库和新的质谱数据采集模式,Mad-CASP技术可从单个HeLa细胞中鉴定出124093个蛋白质.随后利用Mad-CASP技术分析了来自健康人和冠状动脉慢性完全闭塞(CTO)患者的240个外周血CD34^(+)单细胞.基于单细胞蛋白图谱,本研究首次揭示外周血CD34^(+)细胞的功能亚型,证实其在CTO进展中的“双刃剑”作用,提示靶向乙醛脱氢酶2在CTO治疗中的潜在作用.综上,本研究利用Mad-CASP技术首次解析了循环CD34^(+)细胞的单细胞蛋白质图谱,提示Mad-CASP技术在稀缺临床样本的单细胞蛋白质组学检测方面极具潜力. 展开更多
关键词 乙醛脱氢酶2 单细胞蛋白质 蛋白质组学 潜在作用 质谱数据 数据采集模式 HELA细胞 快速检测方法
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The proline synthesis enzyme P5CS forms cytoophidia in Drosophila 被引量:2
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作者 Bo Zhang Omür Y.Tastan +6 位作者 Xian Zhou Chen-Jun Guo xuyang liu Aaron Thind Huan-Huan Hu Suwen Zhao Ji-Long liu 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2020年第3期131-143,共13页
Compartmentation of enzymes via filamentation has arisen as a mechanism for the regulation of metabolism.In 2010,three groups independently reported that CTP synthase(CTPS)can assemble into a filamentous structure ter... Compartmentation of enzymes via filamentation has arisen as a mechanism for the regulation of metabolism.In 2010,three groups independently reported that CTP synthase(CTPS)can assemble into a filamentous structure termed the cytoophidium.In searching for CTPS-interacting proteins,here we perform a yeast two-hybrid screening of Drosophila proteins and identify a putative CTPS-interacting protein,△~1-pyrroline-5-carboxylate synthase(P5CS).Using the Drosophila follicle cell as the in vivo model,we confirm that P5CS forms cytoophidia,which are associated with CTPS cytoophidia.Overexpression of P5CS increases the length of CTPS cytoophidia.Conversely,filamentation of CTPS affects the morphology of P5CS cytoophid ia.Finally,in vitro analyses confirm the filament-fo rming property of P5CS.Our work links CTPS with P5CS,two enzymes involved in the rate-limiting steps in pyrimidine and proline biosynthesis,respectively. 展开更多
关键词 CTPS Cytoophidium DROSOPHILA GLUTAMATE P5CS PROLINE
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Mechanism study of trans-lamina cribrosa pressure difference correlated to optic neuropathy in individuals with glaucoma 被引量:3
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作者 Qingfeng Liang Leying Wang xuyang liu 《Science China(Life Sciences)》 SCIE CAS CSCD 2020年第1期148-151,共4页
Glaucoma is the second leading cause of blindness after cataract worldwide.However,among irreversible blinding eye diseases,glaucoma is the primary cause(Liang et al.,2011).To date,most studies have indicated that gla... Glaucoma is the second leading cause of blindness after cataract worldwide.However,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 disease.In 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 follow-up.However,the underlying cause of POAG remains unclear,and there are several theories about its exact etiology.Some mechanisms have presented underlying optic nerve damage,which include the mechanical theory,vascular theory,and the in・volvement of other factors. 展开更多
关键词 GLAUCOMA al. CATARACT
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Deciphering the Role of Fluoroethylene Carbonate towards Highly Reversible Sodium Metal Anodes 被引量:1
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作者 Xueying Zheng Suting Weng +10 位作者 Wei Luo Bo Chen Xiao Zhang Zhenyi Gu Haotian Wang Xiaolu Ye xuyang liu Liqiang Huang Xinglong Wu Xuefeng Wang Yunhui Huang 《Research》 EI CAS CSCD 2022年第2期259-269,共11页
Sodium metal anodes(SMAs)sufer from extremely low reversibility(<20%)in carbonate based clectrolytes-this piece of knowledge gained from previous studics has ruled out the application of carbonate solvents for sodi... Sodium metal anodes(SMAs)sufer from extremely low reversibility(<20%)in carbonate based clectrolytes-this piece of knowledge gained from previous studics has ruled out the application of carbonate solvents for sodium metal batteries.Here,we overturn this conclusion by incorporating fluoroethylene carbonate(FEC)as cosolvent that renders a Na plating/stripping fficiency of>95%with conventional NaPF。salt at a regular concentration(1.0M).The peculiar role of FEC is firstly.unraveled via its involvement into the solvation structure,where a threshold FEC concentration with a coordination number>1.2 is needed in guaranteeing high Na reversibility over the long-term.Specifially,by incorporating an average number of 1.2 FEC molecules into the primary Na*solvation sheath,lowest unoccupied molecular orbital(LUMO)levels of such Nat-FEC solvates undergo further decrease,with spin electrons residing either on the O=C 0(O)moiety of FEC or sharing between Na*and its C=:O bond,which ensures a prior FEC decomposition in passivating the Na surface against other carbonate molecules.Further,by adopting cryogenic tranmission electron microscopy(cryo-TEM),we found that the Na filaments grow into substantially larger diameter from-400nm to>1 pum with addition of FEC upon the threshold value.A.highly crstalline and much thiner(-40 nm)slid-electrolyte interphase(SED)is consequently observed to uniformly wrap the Na surface,in contrast to the severely corroded Na as retrieved from the blank electrolyte.The potence of FEC is further demonstrated in a series of"corrosive solvents"such as ethy!l acetate(EA)。trimethyl phosphate(TMP),and actonitrile(AN)enabling highly reversible SMAs in the otherwise unusable solvent systems. 展开更多
关键词 ELECTROLYTE otherwise HIGHLY
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Multi-Clock Snapshot Isolation Concurrency Control for NVM Database
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作者 xuyang liu Kang Chen +3 位作者 Mengxing liu Shiyu Cai Yongwei Wu Weimin Zheng 《Tsinghua Science and Technology》 SCIE EI CAS CSCD 2022年第6期925-938,共14页
Multi-Clock Snapshot Isolation(MCSI)is a concurrency control mechanism that implements snapshot isolation on a single-layer Non-Volatile Memory(NVM)database.It stores a single copy of data by using multi-version stora... Multi-Clock Snapshot Isolation(MCSI)is a concurrency control mechanism that implements snapshot isolation on a single-layer Non-Volatile Memory(NVM)database.It stores a single copy of data by using multi-version storage to ensure durability and runtime access.With 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 NVM.For evaluation,we compared MCSI with the PostgreSQL-style concurrency control used in the single-layer NVM database N2DB.The 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 workloads.Moreover,the transaction latency of MCSI remains relatively stable as the thread count increases.With 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. 展开更多
关键词 Non-Volatile Memory(NVM) snapshot isolation Multi-Version Concurrency Control(MVCC) vector clock
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双眼鼻侧视网膜病变所致双颞侧视野缺损四例
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作者 阳铭 曹娟辉 +4 位作者 胡玉章 李丹丽 张晓光 樊宁 刘旭阳 《中华眼视光学与视觉科学杂志》 CAS CSCD 2020年第7期540-545,共6页
病例1患者,女,18岁,因"右眼视力下降数月"于2015年5月24日来院就诊。患者自觉右眼颞侧视物遮挡,不伴其余眼部及全身不适,否认夜盲史。无外伤史、眼病和全身病史,否认家族中类似情况者。眼部检查:右眼裸眼视力(UCVA).0.16,矫... 病例1患者,女,18岁,因"右眼视力下降数月"于2015年5月24日来院就诊。患者自觉右眼颞侧视物遮挡,不伴其余眼部及全身不适,否认夜盲史。无外伤史、眼病和全身病史,否认家族中类似情况者。眼部检查:右眼裸眼视力(UCVA).0.16,矫正无提高;左眼UCVA 1.0。 展开更多
关键词 视网膜病变 右眼视力 眼部检查 裸眼视力 夜盲 VA
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Garbage Collection and Data Recovery for N2DB
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作者 Shiyu Cai Kang Chen +3 位作者 Mengxing liu xuyang liu Yongwei Wu Weimin Zheng 《Tsinghua Science and Technology》 SCIE EI CAS CSCD 2022年第3期630-641,共12页
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 storag... 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. 展开更多
关键词 Non-Volatile Memory(NVM) Garbage Collection(GC) data recovery
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Efficiency measurement for mixed two-stage nonhomogeneous network processes with shared extra intermediate resources
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作者 Qingxian AN xuyang liu Shijie DING 《Frontiers of Engineering Management》 2020年第2期259-274,共16页
Unreasonable allocation of shared resources reduces the system efficiency and is a considerable operational risk.Sub-processes with insufficient portion of shared resources could not help accomplish complicated tasks,... Unreasonable allocation of shared resources reduces the system efficiency and is a considerable operational risk.Sub-processes with insufficient portion of shared resources could not help accomplish complicated tasks,and overstaffing and idle resources will occur in the sub-processes assigned with redundant shared resources.This unfair portion distribution may cause internal contradictions among sub-processes and even lead to the collapsing of the entire system.This study proposes a data-driven,mixed two-stage network data envelopment analysis model.This method aims to reasonably define the allocation portion of shared extra intermediate resources among several nonhomogeneous subsystems and measure the overall system performance.A data set of 58 international hotels is used to test the features of the proposed model. 展开更多
关键词 shared resource allocation mixed two-stage system data envelopment analysis efficiency
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