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Photosynthetic properties of the mid-vein and leaf lamina of field-grown, high-yield hybrid rice during senescence

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Journal of Integrative Agriculture 2022年第7期21卷 1913-1926页

作者： GAO Zhi-ping XU Min-li ZHANG hai-zi Lü chuan-gen CHEN guo-xiang College of Life Sciences Nanjing Normal UniversityNanjing 210023P.R.China Institute of Food and Crops Jiangsu Academy of Agricultural SciencesNanjing 210014P.R.China

Previous studies with rice(Oryza sativa L.) have shown that the different components of the photosynthetic apparatus are not uniformly synthesized or degraded during senescence. However, while most of those studies have focused on the leaf lamina, few have addressed senescence-associated chloroplast function or leaf physiology. Here, we investigated the photosynthetic properties of the mid-vein and leaf lamina in a high-yield hybrid rice cultivar(Liangyoupei 9, LYP9) during the senescence stage. Assimilation and transpiration decreased more slowly in the mid-vein than in the lamina during senescence, suggesting more sustained photosynthesis in the mid-vein, as well as stronger heat dissipation. Two-dimensional gel electrophoresis suggested that photosynthesis and energy metabolism were less affected by senescence in the mid-vein than in the leaf lamina. During late senescence, the excess energy dissipation in the midvein through the xanthophyll cycle had a higher active photosynthetic capacity than in the leaf lamina, and we inferred that the mid-vein and leaf lamina of LYP9 rice differed in terms of their maturation. Taken together, these results provide new insights into the underlying mechanisms of senescence of the rice mid-vein and associated physiology.

关键词： mid-vein rice photosynthetic properties senescence

A distributed Grid-Xinanjiang model with integration of subgrid variability of soil storage capacity

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Water Science and Engineering 2016年第2期9卷 97-105页

作者： Wei-jian guo chuan-hai Wang Teng-fei Ma Xian-min Zeng hai Yang PowerChina Huadong Engineering Corporation Limited Hangzhou 311122 China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University Nanjing 210098 China College of Hydrology and Water Resources Hohai University Nanjing 210098 China

Realistic hydrological response is sensitive to the spatial variability of landscape properties. For a grid-based distributed rainfall-runoff model with a hypothesis of a uniform grid, the high-frequency information within a grid cell will be gradually lost as the resolution of the digital elevation model(DEM) grows coarser. Therefore, the performance of a hydrological model is usually scale-dependent. This study used the GridXinanjiang(GXAJ) model as an example to investigate the effects of subgrid variability on hydrological response at different scales. With the aim of producing a more reasonable hydrological response and spatial description of the landscape properties, a new distributed rainfall-runoff model integrating the subgrid variability(the GXAJSV model) was developed. In this model, the topographic index is used as an auxiliary variable correlated with the soil storage capacity. The incomplete beta distribution is suggested for simulating the probability distribution of the soil storage capacity within the raster grid. The Yaogu Basin in China was selected for model calibration and validation at different spatial scales.Results demonstrated that the proposed model can effectively eliminate the scale dependence of the GXAJ model and produce a more reasonable hydrological response.

关键词： Scale effect Subgrid variability Soil storage capacity Incomplete beta distribution GXAJSV model

Recent progress in synthesis of composite powders and their applications in low-carbon refractories

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Journal of Iron and Steel Research(International) 2022年第7期29卷 1041-1051页

作者： Ji-yuan Luo Xin-ming Ren Xiao-chuan Chong Dong-hai Ding Bei-yue Ma guo-qing Xiao Jing-kun Yu College of Materials Science and Engineering Xi’an University of Architecture and TechnologyXi’an 710055ShaanxiChina School of Metallurgy Northeastern UniversityShenyang 110819LiaoningChina

The development of low-carbon refractories is of great significance,but it is limited by the deteriorated properties that resulted from the decreased graphite content.Incorporating composite powders has proved to be effective in improving the properties of low-carbon refractories.The recent progress in the synthesis of composite powders including modified graphite,nanocarbon-containing composite powders,oxide/non-oxide and non-oxide composite powders and their applications in low-carbon refractories were reviewed,and the future development of composite powder technology was prospected.

关键词： Composite powder Modified graphite Nanocarbon-containing composite powder Oxide/non-oxide Non-oxide Low-carbon refractory

Large margin classification for combatingdisguise attacks on spam filters

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Journal of Zhejiang University-Science C(Computers and Electronics) 2012年第3期13卷 187-195页

作者： Xi-chuan ZHOU hai-bin SHEN Zhi-yong HUANG guo-jun LI College of Communications Engineering Chongqing UniversityChongqing40044China Institute of VLSI Design Zhejiang UniversityHangzhou 310027China Chongqing Communication Institute Chongqing 400032China

This paper addresses the challenge of large margin classification for spam filtering in the presence of an adversary who disguises the spam mails to avoid being detected. In practice, the adversary may strategically add good words indicative of a legitimate message or remove bad words indicative of spam. We assume that the adversary could afiord to modify a spam message only to a certain extent, without damaging its utility for the spammer. Under this assumption, we present a large margin approach for classification of spam messages that may be disguised. The proposed classifier is formulated as a second-order cone programming optimization. We performed a group of experiments using the TREC 2006 Spam Corpus. Results showed that the performance of the standard support vector machine (SVM) degrades rapidly when more words are injected or removed by the adversary, while the proposed approach is more stable under the disguise attack.

关键词：大边缘垃圾过滤秒顺序锥编程(SOCP ) 对手的分类

Free and Hidden Fumonisins in Hordei Fructus Germinatus and Their Transfer to the Decoction

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World Journal of Traditional Chinese Medicine 2020年第1期6卷 106-111页

作者： Ling Hu hai-Qiang Zhu Mei-Lin Ni Jian Yang chuan-Zhi Kang Lan-Ping guo Ningbo Academy of Inspection and Quarantine China Academy of Chinese Medical SciencesBeijingChina Ningbo National Resource Center for Chinese Materia MedicaChina Academy of Chinese Medical SciencesBeijingChina

Objective:This study aimed to determine the free and hidden fumonisins in Hordei Fructus Germinatus samples and to investigate the transfer rates of these mycotoxins from Hordei Fructus Germinatus to its decoction.Materials and Methods:The contamination levels of free and hidden fumonisins in a total of 60 Hordei Fructus Germinatus samples were analyzed using high-performance liquid chromatography coupled to tandem mass spectrometry(LC-MS/MS).The decoction procedure was simulated with a highly contaminated Hordei Fructus Germinatus sample,and fumonisins in the resulting decoction preparation were determined by LC-MS/MS.Results:Among all the samples,8.3%were contaminated with free fumonisins(FB1 and/or FB2)and 13.3%were contaminated with total fumonisins(free+hidden,measured as hydrolyzed fumonisins,i.e.,HFB1 and/or HFB2).The concentrations of FB1 and HFB1 reached up to 83 and 95μg/kg,respectively,whereas FB2 and HFB2 were detected only in traces.The transfer rates of free and total fumonisins from Hordei Fructus Germinatus to the decoction were 71.8%and 83.3%for FB1 and FB2,respectively.In comparison,much lower transfer rates were found for total fumonisins,i.e.,38.2%and 24.7%for HFB1 and HFB2,respectively.Conclusion:The incidence and contamination levels of free and hidden fumonisins in Hordei Fructus Germinatus samples were generally low.Regarding decoction preparation,the transfer rates of free fumonisins into the decoction were high,whereas a large part of hidden fumonisins were retained in Hordei Fructus Germinatus rather than migrating into water.

关键词： Decoction fumonisins hidden fumonisins Hordei Fructus Germinatus liquid chromatography coupled to tandem mass spectrometry transfer rate

Family history of esophageal cancer modifies the association of serum lipids and malignant esophageal lesions:a nested case-control study from the"Endoscopic Screening for Esophageal Cancer in China"trial

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Chinese Medical Journal 2021年第9期134卷 1079-1086页

作者： Min-Min Wang Chuan-Hai Guo Feng-Lei Li Rui-Ping Xu Zhen Liu Ya-Qi Pan Fang-Fang Liu Ying Liu Hong Cai Meng-Fei Liu Zhong-Hu He Yang Ke Key Laboratory of Carcinogenesis and Translational Research(Ministry of Education/Beijing) Laboratory of GeneticsPeking University Cancer Hospital and InstituteBeijing 100142China Hua County People's Hospital AnyangHenan 456400China Anyang Cancer Hospital AnyangHenan 455000China

Background:The association of lipids and cancer has varied greatly among different cancer types,lipid components and study populations.This study is aimed to investigate the association of serum lipids and the risk of malignant lesions in esophageal squamous epithelium.Methods:In the"Endoscopic Screening for Esophageal Cancer in China"(ESECC)trial,serum samples were collected and tested for total cholesterol(TC),triglycerides,low-density lipoprotein cholesterol(LDL-C),and high-density lipoprotein cholesterol at the time of subject enrollment.Cases were defined as malignant esophageal lesions identified by baseline endoscopic examination or by follow-up to May 31,2018.Controls were randomly selected using incidence density sampling in the same cohort.Conditional logistic models were applied to identify the association of serum lipids and the risk of malignant esophageal lesions.Effect modification was evaluated by testing interaction terms of the factor under assessment and these serum lipid indicators.Results:No consistent association between serum lipid levels and esophageal malignant lesions were found in a pooled analysis of 211 cases and 2101 controls.For individuals with a family history of esophageal cancer(EC),high TC,and LDL-C were associated with a significantly increased risk of having malignant lesions(odds ratio[OR]Highvs.Low TC=2.22,95%confidence interval[CI]:1.14-4.35;ORHighvs.Low LDL-C=1.93,95%CI:1.01-3.65).However,a negative association was observed in participants without an EC family history(ORHighvs.Low TC=0.69,95%CI:0.48-0.98,Pinteraction=0.002;ORHighvs.Low LDL-C=0.50,95%CI:0.34-0.76,Pinteraction<0.001).Conclusions:In this study,we found that the association of serum lipids and malignant esophageal lesions might be modified by EC family history.The stratified analysis would be crucial for population-based studies investigating the association of serum lipids and cancer.The mechanism by which a family history of EC modifies this association warrants further investigation.

关键词： Effect modification Esophageal squamous cell carcinoma Family history Genetic susceptibility Lipids and lipoprotein

Self-assembled semiconductor quantum dots decorating the facets of GaAs nanowire for single-photon emission

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National Science Review 2017年第2期4卷 196-209页

作者： Ying Yu guo-Wei Zha Xiang-Jun Shang Shuang Yang Ban-Quan Sun hai-Qiao Ni Zhi-chuan Niu State Key laboratory for Superlattice and Microstructures Institute of SemiconductorsChinese Academy of Sciences State Key Laboratory of Optoelectronic Materials and Technologies School of electronics and information technologySun Yat-sen University College of Materials Science and Opto-Electronic Technology University of Chinese Academy of Sciences Synergetic Innovation Center of Quantum Information& Quantum Physics University of Science and Technology of China

In this chapter, we discuss the epitaxial growth of self-assembled quantum dots(QDs) in GaAs nanowires(NWs) and the characteristics of their single-photon emissions. We demonstrate Ga droplet-induced gold-free vapor-liquid-solid growth of hexagonal GaAs/Al GaAs core–shell NWs, branched GaAs NWs and tailored nanostructured morphologies on the NW facets. Particularly, we show two new types of QD-in-NW systems: one is a single InAs QD formed at the corner of a branched GaAs NW, and the other is a single GaAs QD formed on the NW facet. Sharp excitonic emission spectral lines are observed with vanishing two-photon emission probability. Furthermore, a single GaAs QD is achieved at the site of a single Al GaAs quantum ring(QR) on the NW facet. In addition, these NW-based single QDs are in-situ probed and integrated with single-mode optical ibers to achieve all-iber-output single-photon sources for potential application in quantum integrated networks.

关键词： self-assembled nanowires quantum dots single photon emitters molecular beam epitaxy

AtFH8 Is Involved in Root Development under Effect of Low-Dose Latrunculin B in Dividing Cells

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Molecular Plant 2011年第2期4卷 264-278页

作者： Xiu-Hua Xue Chun-Qing guo Fei Du Quan-Long Lu chuan-Mao Zhang hai-Yun Ren Key Laboratory of Cell Proliferation and Regulation Biology of Ministry of Education College of Life Sciencer Beijing Normal Universityl Beijing 100875China The Key Laboratory of Cell Proliferation and Differentiation of Ministry of Education and the State Key Laboratory of Bio-Membrane and Membrane Bio-Engineering College of Life Science Peking University Beijing 100871 China

Formins have been paid much attention for their potent nucleating activity. However, the connection between the in vivo functions of AtFHs （Arabidopsis thaliana formin homologs） and their effects on actin organization is poorly understood, in this study, we characterized the bundling activity of AtFH8 in vitro and in vivo. Biochemical analysis showed that AtFH8（FH1FH2） could form dimers and bundle preformed actin filaments or induce stellar structures during actin polymerization. Expression of truncated forms of AtFH8 and immunolocalization analysis showed that AtFH8 localized primarily to nuclear envelope in interphase and to the new cell wall after cytokinesis, depending primarily on its N-terminal transmembrane domain. GUS histochemical staining showed AtFH8 was predominantly expressed in Arabidopsis root meristem, vasculature, and outgrowth points of lateral roots. The primary root growth and lateral root initiation of atfh8 could be decreased by latrunculin B （LatB）. Analysis of the number of dividing cells in Arabidopsis root tips showed that much fewer dividing cells in Lat B-treated atfh8 plants than wild-type plants, which indicates that AtFH8 was involved in cell division. Actin cytoskeleton in root meristem of atfh8-1 was more sensitive to LatB treatment than that of wild-type. Altogether, our results indicate that AtFH8 is an actin filament nucleator and bundler that functions in cell division and root development.

关键词： Actin binding protein formin cell division root meristem lateral root initiation actin nucleator and bundler.

A TIME DOMAIN INVESTIGATION ON THE HYDRODYNAMIC RESONANCE PHENOMENA OF 3-D MULTIPLE FLOATING STRUCTURES

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Journal of Hydrodynamics 2008年第5期20卷 611-616页

作者： ZHU hai-rong ZHU Ren-chuan MIAO guo-ping The State Key Laboratory of Ocean Engineering School of Naval Architecture Ocean and Civil Engineering Shanghai Jiao Tong University Shanghai 200030 China

A 3-D time domain method is developed to investigate the gap influence on the wave threes for 3-D multiple floating structures. Special hydrodynamic resonance due to small gaps between multiple floating structures on wave forces is examined. Strong and complicate hydrodynamic interactions between the floating bodies are observed and the numerical computations have proved the existence of the sharp peak force response on each floating body at some special resonant wave numbers. By comparison with the results from the frequency domain technique, the results obtained from the time domain method reveal the similar resonant phenomena and hydrodynamic interaction. The resonant wave numbers are also proved around kL-nπ （n = 1,2 ……∞） with a corresponding frequency shift. The strong hydrodynamic interaction feature is practically significant for the design of module structures and the links （connection） in whole the floating body system.

关键词： time domain resonance hydrodynamic interaction multiple floating bodies gap influence