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ON NECESSITY OF PLACING AN AERATOR IN THE BOTTOM DISCHARGE TUNNEL AT THE LONGTAN HYDROPOWER STATION

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Journal of Hydrodynamics 2006年第6期18卷 698-701页

作者： WU Jian-hua WU wei-wei RUAN shi-ping College of Water Conservancy and Hydropower Engineering Hohai University Nanjing 210098 China

The air entrainment for avoiding cavitation damage has been widely used in long free flow tunnels. It is crucial to determine whether an aerator is needed for shorter tunnels. In this article, the bottom discharge tunnel at the Longtan Hydropower Station was involved, for which the free flow tunnel section was only 50.00 m long. The cavitation in the tunnel with and without the aerator was investigated using the physical models of the scale 1/30, through the measurements of cavitation noise. The experimental results show that it is necessary to place the aerator at the inlet of the free flow section for higher reservoir level to protect this tunnel from cavitation damage.

关键词： aerator bottom discharge tunnel cavitation damage cavitation noise Longtan Hydropower Station

Hydrogen Peroxide in Plants:a Versatile Molecule of the Reactive Oxygen Species Network

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Journal of Integrative Plant Biology 2008年第1期50卷 2-18页

作者： Li-Juan Quan Bo Zhang wei-wei shi Hong-Yu Li MOE Key Laboratory of Arid and Grassland Ecology School of Life Sciences Lanzhou University Lanzhou 730000 China

Plants often face the challenge of severe environmental conditions, which include various biotic and abiotic stresses that exert adverse effects on plant growth and development. During evolution, plants have evolved complex regulatory mechanisms to adapt to various environmental stressors. One of the consequences of stress is an increase in the cellular concentration of reactive oxygen species （ROS）, which are subsequently converted to hydrogen peroxide （H2O2）. Even under normal conditions, higher plants produce ROS during metabolic processes. Excess concentrations of ROS result in oxidative damage to or the apoptotic death of cells. Development of an antioxidant defense system in plants protects them against oxidative stress damage. These ROS and, more particularly, H2O2, play versatile roles in normal plant physiological processes and in resistance to stresses. Recently, H2O2 has been regarded as a signaling molecule and regulator of the expression of some genes in cells. This review describes various aspects of H2O2 function, generation and scavenging, gene regulation and cross-links with other physiological molecules during plant growth, development and resistance responses.

关键词： antioxidant system gene regulation hydrogen peroxide (H2O2) reactive oxygen species (ROS) signaling molecule.

Overexpression of a Foreign Bt Gene in Cotton Affects the Low-Molecular-weight Components in Root Exudates

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Pedosphere 2007年第3期17卷 324-330页

作者： YAN wei-Dong shi wei-Ming LI Bao-Hai ZHANG Min State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing210008 （China）

Most research in the past using genetically modified crops (GM crops) has focused on the ecological safety of foreign gene (i.e., the gene flow), gene products (for example, Bt (Bacillus thuringiensis) protein), and the safety of transgenic food for humans. In this study, changes in both the species and amounts of low-molecular-weight components in cotton (Gossypium hirsutum L.) root exudates after foreign Bt gene overexpression were investigated under different nutritional conditions. Transgenic cotton containing Bt (Bt-cotton), supplemented with all the mineral nutrients, secreted more organic acids than the wild-type cotton (WT). When nitrogen was removed from the full-nutrient solution, the amount of organic acids secretion of Bt-cotton was lesser than that of WT. The roots of the transgenic cotton secreted lesser amounts of amino acids and soluble sugars than the WT roots in the full-nutrient solution. Deficiencies of P and K caused a large increase in the total amino acid and soluble sugar secretions of both Bt-cotton and WT, with larger increases observed in Bt-cotton. Because transferring the foreign Bt gene into cotton can result in alterations in the components of the root exudates, with the effect varying depending on the nutritional status, the cultivation of genetically modified crops, such as Bt-cotton, in soil environments should be more carefully assessed, and the possible effects as a result of the alterations in the root exudate components should be considered.

关键词： gene overexpression low-molecular-weight components nutritional status root exudates transgenic cotton

Age-dependent expression of forkhead box O proteins in the duodenum of rats

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2011年第9期12卷 730-735页

作者： Pan HUANG Zhen-qi ZHOU Rui-hua HUANG Bo ZHOU Quan-wei wei Fang-xiong shi College of Animal Science and Technology Nanjing Agricultural UniversityNanjing 210095China

The O subfamily of forkhead box(FoxO) proteins is the downstream effector of the insulin-like growth factor-1/phosphoinositide 3-kinase/protein kinase B(IGF-1/PI3K/PKB) signal *** objective of the present study was to examine the expressions of three members of FoxO proteins,FoxO1,FoxO3a,and FoxO4 in the duodenum of Sprague-Dawley rats at different *** result demonstrated that the expression of FoxO4 in rat duodenum showed an age-dependent *** Day 21,there were no detectable localization and expression of FoxO4 in the duodenum,while,at Months 2 and 6,localization and expression of FoxO4 were *** addition,FoxO4 staining was primarily concentrated in the cell nuclei of the lamina propria around the intestinal gland of the duodenum in 2-month-old rats,but was not detectable in the same area in 6-month-old *** results showed also that although FoxO3a existed in the cytoplasm of the lamina propria at a low level at the 2-and 6-month marks,it was still not detectable at Day ***,FoxO1 was not detectable in all parts and *** together,our findings suggested that the cell-specific and age-dependent expressional patterns of FoxO4 and FoxO3a proteins in the duodenum play some roles in the development and growth performance of the rat duodenum.

关键词： O subfamily of forkhead box(FoxO) Age-dependence Duodenum Rat

HYDRAULIC CHARACTERISTICS OF PARTIAL OPENING OF THE WORKING GATE FOR A DISCHARGE TUNNEL

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Journal of Hydrodynamics 2007年第4期19卷 488-493页

作者： WU Jian-hua FENG Shu-rong WU wei-wei RUAN shi-ping College of Water Conservancy and Hydropower Engineering Hohai University Nanjing 210098 China China Hydro Mid-South Design and Research Institute Changsha 410014 China

The partial opening of the working gate for a discharge tunnel is used more and more widely in the various conditions, such as releasing discharge to meet the needs of the various stages under construction, or of the operations at low reservoir levels. In this article the hydraulic characteristics were investigated of the partial opening of the working gate based on the physical model experiments of the discharge tunnel for the Longtan Hydropower Project, including the discharge coefficient, the surface profile of the free flow section, the bottom pressure distribution of the tunnel with an aerator, the cavity length just from the ramp, and the wall pressure of the curve section of the outlet. Some new issues were discussed and the properties were presented of the partial opening of the gate.

关键词： partial opening hydraulic characteristics working gate discharge tunnel

Comparative Analysis of Gene Expression in Two Muskmelon Cultivars(Cucumis melo L.) Under Salt Stress

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Journal of Integrative Agriculture 2014年第10期13卷 2132-2140页

作者： wei shi-wei ZHANG Fu-rong ZHANG Yi-dong WANG Li-min CHEN Jia-bei HUANG Dan-feng Department of Plant Science School of Agriculture and BiologyShanghai Jiao Tong University/Key Laboratory of Urban Agriculture (South)Ministry of Agriculture

Salinity is one of the most important abiotic stresses that adversely affects crop growth and productivity. A subtractive suppression hybridization （SSH） library were constructed from the roots of salt-sensitive Yulu cultivar melon seedlings under salt stress; 557 high-quality expressed sequence tags （ESTs） were randomly sequenced, with an average size of 428 bp, which assembled into 68 contigs and 315 singletons. Compared with our previous SSH library generated from the salt-tolerant Bingxuecui cultivar, the proportion of transcripts involved in metabolism, protein fate, cellular communication/signal transduction mechanisms, and cell rescue/defense were 4, 1.46, 0.94, and 0.4% higher, respectively, in the salt-tolerant cultivar than the in salt-sensitive cultivar. Quantitative real-time PCR analysis of eleven transcripts revealed temporal variations in their expression in the two cultivars under salt stress. One NAC gene （JZ477011） was heterologously expressed in yeast for functional characterization, and enhanced the sensitivity of yeast cells to high-salinity to salt stress and inhibited their growth. Information regards to their functions would aid in the understanding of response mechanisms to saline stress and in the development of molecular markers for selecting salt-tolerant melon cultivars.

关键词： comparative analysis functional characterization gene expression salt stress SSH melon cultivars

Super-resolution filtered ghost imaging with compressed sensing

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Chinese Physics B 2020年第12期29卷 119-124页

作者： Shao-Ying Meng wei-wei shi Jie Ji Jun-Jie Tao Qian Fu Xi-Hao Chen Ling-An Wu Key Laboratory of Optoelectronic Devices and Detection Technology School of PhysicsLiaoning UniversityShenyang 110036China Institute of Physics Chinese Academy of SciencesBeijing 100190China

A filtered ghost imaging(GI)protocol is proposed that enables the Rayleigh diffraction limit to be exceeded in an intensity correlation system;a super-resolution reconstructed image is achieved by low-pass filtering of the measured *** a lensless GI experiment performed with spatial bandpass filtering,the spatial resolution can exceed the Rayleigh diffraction bound by more than a factor of *** resolution depends on the bandwidth of the filter,and the relationship between the two is investigated and *** combination with compressed sensing programming,not only high resolution can be maintained but also image quality can be improved,while a much lower sampling number is sufficient.

关键词： ghost imaging bandpass filtering compressed sensing super resolution

Chimeric protein probes for C5a receptors through fusion of the anaphylatoxin C5a core region with a small-molecule antagonist

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Science China Chemistry 2019年第10期62卷 1371-1378页

作者： Chao Zuo wei-wei shi Xiao-Xu Chen Marie Glatz Bernd Riedl Ingo Flamme Elisabeth Pook Jiawei Wang Ge-Min Fang Donald Bierer Lei Liu Tsinghua-Peking Center for Life Sciences Ministry of Education Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical BiologyCenter for Synthetic and Systems BiologyDepartment of ChemistryTsinghua UniversityBeijing 100084China School of Life Science Institutes of Physical Science and Information TechnologyAnhui UniversityHefei 230601China Bayer AG Department of Medicinal ChemistryAprather Weg 18A42096 WuppertalGermany Bayer AG Cardiovascular Research42096 WuppertalGermany Bayer AG Lead Discovery42096 WuppertalGermany

Blockade of the interaction of anaphylatoxin C5a with its receptor C5aR1 has been actively studied as a potential treatment for many inflammatory diseases;but current C5a antagonists exhibit inadequate potency and poor species cross-reactivity, and novel biochemical tools are needed to investigate whether the core region of C5a contains important interaction epitopes that can explain these limitations. Herein, we report the development of chimeric protein C5a probes containing both the complete core region of rat or human C5a, and the small-molecule antagonist PMX53-1. These probes were chemically synthesized through hydrazide-based native chemical ligation of a linear peptide hydrazide with the requisite cyclopeptidic antagonist, both of which were made by solid-phase synthesis. Quasi-racemic X-ray crystallography established that attachment of PMX53-1 did not affect the structure of the core region of C5a. Subsequent C5aR1 activity assays demonstrated the probes can provide valuable insights into the development of C5a antagonists;for example, they exhibited significantly better binding affinity and much improved species cross-reactivity than PMX53-1, supporting the notion that the effect of some epitopes outside the C-terminus of C5a should be taken into consideration when designing better C5a antagonists. Surprisingly, the core region of C5a was found to partially agonize C5aR1, suggesting the presence of more than one agonistic interaction in the binding of C5a to C5aR1. This study exemplifies the value of chemical protein synthesis in developing novel receptor probes for drug discovery research.

关键词： anaphylatoxin C5a PMX53 quasi-racemic X-ray crystallography native chemical ligation

Iterative filtered ghost imaging

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Chinese Physics B 2022年第2期31卷 681-686页

作者： Shao-Ying Meng Mei-Yi Chen Jie Ji wei-wei shi Qiang Fu Qian-Qian Bao Xi-Hao Chen Ling-An Wu Key Laboratory of Optoelectronic Devices and Detection Technology School of PhysicsLiaoning UniversityShenyang 110036China Institute of Physics Chinese Academy of SciencesBeijing 100190China

It is generally believed that,in ghost imaging,there has to be a compromise between resolution and *** we propose and demonstrate an iterative filtered ghost imaging scheme whereby a super-resolution image of a grayscale object is achieved,while at the same time the signal-to-noise ratio(SNR)and visibility are greatly improved,without adding *** dependence of the SNR,visibility,and resolution on the number of iterations is also investigated and ***,with the use of compressed sensing the sampling number can be reduced to less than 1%of the Nyquist limit,while maintaining image quality with a resolution that can exceed the Rayleigh diffraction bound by more than a factor of 10.

关键词： ghost imaging bandpass filtering compressed sensing iteration