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A New Text Location Approach Based Wavelet

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计算机科学 2002年第Z1期29卷 105-106,114页

作者： Weihua li Zhen fang Shuozhong wang 上海交通大学通信与信息工程学院上海200072 上海交通大学通信与信息工程学院上海200072 上海交通大学通信与信息工程学院上海200072

With the advancement of content-based retrieval technology, the importance of semantics for text information contained in images attracts many researchers. An algorithm which will automatically locate the textual regions in the input image will facilitate the retrieving task, and the optical character recognizer can then be applied to only those regions of the image which contain text. In this paper a new text location method based wavelet is described, which can be used to locate textual regions from complex image and video frame. Experimental results show that the textual regions in image can be located effectively and quickly.

关键词： Text location, 2-D wavelet, Morphological operation

Synergy and Redundancy in a Signaling Cascade with Different Feedback Mechanisms

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Communications in Theoretical Physics 2018年第10期70卷 485-495页

作者： li-fang wang Ying Xu Jun Ma Ya Jia Department of Physics and Institute of Biophysics Central China Normal University Wuhan 430079 China Department of Physics Lanzhou University of Technology Lanzhou 730050 China NAAM-Research Group Department of Mathematics Faculty of Science King Abdulaziz University P. O. Box 80203 Jeddah 21589 Saudi Arabia

Feedback plays an important role in various biological signal transmission systems. In this paper, a signaling cascade system(including three layers: input(S), intermediate(V), output(X) components) is employed to study the fluctuations and net synergy in information transmission, in which the V component is regulated by itself or the X component, and each feedback on V is either positive or negative. The Fano factor, the net synergy, and the signalto-noise ratio(SNR) of signaling cascade with the four possible feedback types are theoretically derived by using linear noise approximation of the master equation, and the ability of information transmission through the signaling cascade is characterized by using the partial information decomposition of information theory. It is found that the signaling cascade exhibits different responses to the four feedback mechanisms, which depend on the relationships between degradation rates of components. Our results not only clarify the dependence of the Fano factor, net synergy, and SNR on the feedback regulations with the varying of degradation rates of components, but also imply that living cells could utilize different feedback mechanisms to adapt to the external fluctuating environments.

关键词： stochastic theory biological signaling transmission cascade feedback

Transgene directionally integrated into C-genome of Brassica napus

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Chinese Science Bulletin 2006年第13期51卷 1578-1585页

作者： li Jun fang Xiaoping wang Zhuan LUO lixia HU Qiong Key Laboratory of Oil Crops Genetic Improvement of the Ministry of Agriculture Institute of Oil Crops Research Chinese Academy of Agricultural Sciences Wuhan 430062 China

Integration of a transgene into a C-genome chromosome plays an important role in reducing ecological risk of transgenic Brassica napus To obtain C-genome transgenic B. napus, herbi- cide-resistant bar gene was firstly transferred into B. oleracea var. alboglabra mediated by Agrobacterium tumefaciens strain LBA4404. Then using the trans- genic B. oleracea as paternal plants and 8 non- transgenic varieties of B. rapa as maternal plants, C- genome transgenic B. napus with bar gene was arti- ficially resynthesized by means of ovary culture and chromosome doubling. Among 67 lines of the resyn- thesized B. napus, 31 were positive, and 36 were negative according to PCR test for bar gene. At least 2 plants from each line were kept for PPT spray con- firmation. The result was in consistence with the PCR test. Genomic Southern blotting of three randomly chosen lines also showed that bar gene had been integrated into the genome of resynthesized B. napus lines.

关键词： C-染色体组 Bar基因定向转基因芸苔再合成

Kinetic Monte Carlo code development and application on the formation of hydrogen-vacancy clusters in tungsten

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Science China(Physics,Mechanics & Astronomy) 2019年第1期62卷 83-89页

作者： Chao Meng JianNan Hao Ke Xu li-fang wang Xiaolin Shu Shuo Jin Guang-Hong Lu Department of Physics Beihang University Beijing Key Laboratory of Advanced Nuclear Materials & Physics Beihang University

We have developed an object kinetic Monte Carlo(OKMC)code and simulated hydrogen-vacancy clustering behavior and dependence on temperature and hydrogen-vacancy ratio in *** each of the temperatures we simulated from 300 K to1000 K,H_nV clusters with smaller n form before those with larger *** elevating temperature leads to a decrease in hydrogen vacancies:H_(10)V and H_9V clusters dominate at 300 K and 600 K,whereas H_5V,H_6V,and H_7V clusters dominate when the temperature reaches 1000 ***,only H_nV clusters with smaller n formed when a lower hydrogen-vacancy ratio was used due to insufficient availability of hydrogen atoms to occupy *** results suggest hydrogen emission occurs very rarely at lower temperatures,while higher temperatures facilitate the dissociation of hydrogen from H_nV clusters.

关键词： tungsten hydrogen vacancy KMC

Optimal Operation with Dynamic Partitioning Strategy for Centralized Shared Energy Storage Station with Integration of Large-scale Renewable Energy

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Journal of Modern Power Systems and Clean Energy 2024年第2期12卷 359-370页

作者： Jianlin li Zhijin fang Qian wang Mengyuan Zhang Yaxin li Weijun Zhang Beijing Future Technology Innovation Centre for Electrochemical Energy Storage System Integration North China University of Technology Beijing China State Grid Fujian Electric Power Research Institute Fuzhou China

As renewable energy continues to be integrated into the grid,energy storage has become a vital technique supporting power system *** effectively promote the efficiency and economics of energy storage,centralized shared energy storage(SES)station with multiple energy storage batteries is developed to enable energy trading among a group of *** this paper,we propose the optimal operation with dynamic partitioning strategy for the centralized SES station,considering the day-ahead demands of large-scale renewable energy power *** implement a multi-entity cooperative optimization operation model based on Nash bargaining *** model is decomposed into two subproblems:the operation profit maximization problem with energy trading and the leasing payment bargaining *** distributed alternating direction multiplier method(ADMM)is employed to address the subproblems *** reveal that the optimal operation with a dynamic partitioning strategy improves the tracking of planned output of renewable energy entities,enhances the actual utilization rate of energy storage,and increases the profits of each participating *** results confirm the practicality and effectiveness of the strategy.

关键词： Shared energy storage(SES) dynamic partitioning strategy optimal operation Nash bargaining theory actual utilization rate of energy storage

Causal Analysis Between Rice Growth and Cadmium Accumulation and Transfer under Arbuscular Mycorrhizal Inoculation

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Rice science 2024年第2期31卷 226-236页

作者： ZHAO Ting wang li YANG Jixian MA fang State Key Laboratory of Urban Water Resource and Environment School of EnvironmentHarbin Institute of TechnologyHarbin 150090China

Cadmium(Cd)contamination in rice has been a serious threat to human *** investigate the effects of arbuscular mycorrhizal fungi(AMF)on the Cd translocation in rice,a controlled pot experiment was *** results indicated that AMF significantly increased rice biomass,with an increase of up to 40.0%,particularly in root biomass by up to 68.4%.Notably,the number of prominent rice individuals also increased,and their plasticity was enhanced following AMF *** led to an increase in the net photosynthetic rate and antioxidant enzyme activity of *** the AMF treatment group,the Cd concentration in the rice roots was significantly higher(19.1%‒68.0%)compared with that in the control ***,the Cd concentration in the rice seeds was lower in the AMF treatment group,indicating that AMF facilitated the sequestration of Cd in rice roots and reduced Cd accumulation in the *** coefficients varied across different treatments,suggesting that AMF inoculation reduced the direct impact of soil Cd concentration on the total Cd accumulation in *** translocation of Cd was consistently associated with simultaneous growth dilution and compensatory accumulation as a result of mycorrhizal *** study quantitatively analyzed this process through path analysis and clarified the causal relationship between rice growth and Cd transfer under the influence of AMF.

关键词： cadmium transfer dilution effect heavy metal immobilization mycorrhizal effect path analysis phenotypic plasticity

A Dietary Source of High Level of Fluoroquinolone Tolerance in mcr-Carrying Gram-Negative Bacteria

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Research 2024年第3期2023卷 105-121页

作者： Tianqi Xu Dan fang Fulei li Zhiqiang wang Yuan liu Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses College of Veterinary MedicineYangzhou UniversityYangzhou 225009China. Joint International Research Laboratory of Agriculture and Agri-Product Safety the Ministry of Education of ChinaYangzhou UniversityYangzhou 225009China. Institute of Comparative Medicine Yangzhou UniversityYangzhou 225009China.

The emergence of antibiotic tolerance,characterized by the prolonged survival of bacteria following antibiotic exposure,in natural bacterial populations,especially in pathogens carrying antibiotic resistance genes,has been an increasing threat to public ***,the major causes contributing to the formation of antibiotic tolerance and underlying molecular mechanisms are yet poorly ***,we show that potassium sorbate(PS),a widely used food additive,triggers a high level of fluoroquinolone tolerance in bacteria carrying mobile colistin resistance gene *** studies demonstrate that PS treatment results in the accumulation of intracellular fumarate,which activates bacterial two-component system and decreases the expression level of outer membrane protein OmpF,thereby reducing the uptake of *** addition,the supplementation of PS inhibits aerobic respiration,reduces reactive oxygen species production and alleviates DNA damage caused by bactericidal ***,we demonstrate that succinate,an intermediate product of the tricarboxylic acid cycle,overcomes PS-mediated ciprofloxacin *** multiple animal models,ciprofloxacin treatment displays failure outcomes in PS preadministrated animals,including comparable survival and bacterial loads with the vehicle *** together,our works offer novel mechanistic insights into the development of antibiotic tolerance and uncover potential risks associated with PS use.

关键词： overcome thereby additive

SO_(2)-Insertion induced enantioselective oxysulfonylation to access β-chiral sulfones with quaternary carbon stereocenters

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Science China Chemistry 2024年第3期67卷 908-913页

作者： Jun Zhang Xuefeng wang Peiqi wang Jiayuan fang Shaoyu li Jie Wu School of Pharmaceutical and Chemical Engineering&Institute for Advanced Studies Taizhou UniversityShanghai 200438China Department of Chemistry Fudan UniversityShanghai 200438China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiang 453007China

β-Chiral sulfones are structural motifs widely found in natural products and bioactive molecules, while also serving as important intermediates for the synthesis of valuable chiral scaffolds. In contrast to the rapid growth of sulfur dioxide insertion chemistry over the last decade, enantioselective catalytic variants for accessing β-chiral sulfones, especially those bearing a quaternary carbon stereocenter, remain rare. Herein, we report an enantioselective copper/bisoxazoline catalyzed oxysulfonylation of alkenes to yield isoxazolinyl-containing β-chiral sulfones bearing quaternary carbon stereocenters with moderate to excellent yields and up to 96:4 er. The advantage and irreplaceability of this sulfur dioxide insertion catalytic system have been demonstrated by achieving transformations clearly unavailable with the previously reported sulfonyl chloride system. Additionally,the recoverability of the new-developed bisoxazoline ligand L9 and its reusability without any erosion of the catalytic activity and enantioselectivity further demonstrate the usefulness of the protocol.

关键词： β-chiral sulfones sulfur dioxide insertion oxysulfonylation copper catalysis enantioselectivity

Conditioning treatments mitigate the levels of fecal pollution indicators in soil during land-application of sewage sludge

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Science China Technological Sciences 2024年第10期67卷 3091-3102页

作者： wang YuHang li Hua fang WenHao wang Ru wang XinXin ZHENG GuanYu ZHOU liXiang Department of Environmental Engineering College of Resources and Environmental SciencesNanjing Agricultural University College of Materials and Chemical Engineering Pingxiang University Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization

Sewage sludge is a major source of fecal pathogens in the environment, and its application to land can result in a significant release of these pathogens into the soil. While conditioning treatments are crucial for improving the dewatering process of sludge, their impact on the presence and behavior of fecal pathogens in soil remains unclear. This study aims to assess four extraction methods for recovering fecal pollution indicators from soil amended with unconditioned and conditioned sludge. The indicators include Escherichia coli(EC), human-specific HF183 Bacteroides(HF183), human adenovirus(HAdV), human BK polyomavirus(BKPyV), human JC polyomavirus(JCPyV), and cross-assembly phage(crAssphage). This study also examines how soil moisture content affects the decay of these fecal pollution indicators in soil amended with raw sludge and investigates the influence of conditioning treatments with cationic polyacrylamide(PAM), Fenton's reagents, Fe[Ⅲ]/CaO on their persistence in soil. The results indicated that the direct extraction method was the most effective and unbiased for recovering fecal pollution indicators from sludge-amended soil compared with the three elution-concentration methods. All fecal pollution indicators, except HAdV, remained stable under dry soil conditions, while high soil moisture content(48.39%-53.14%) slowed the decay rates of these indicators. During the application of sludge to soil, effective control of fecal pollution indicators was observed, with JCPyVand HAdV becoming undetectable within a short period. The log reduction values of HF183, BKPyV, and crAssphage ranged from 0.1 to 2.8 logs after 30 d of cultivation. The application of conditioned sludge, especially Fenton's reagent-conditioned sludge, resulted in a reduction in human fecal contamination in the receiving soil. Therefore, implementing appropriate conditioning methods, such as using Fenton's reagent, can effectively mitigate the health risks associated with fecal pathogens.

关键词： fecal pollution indicators sewage sludge conditioning treatment land application soil

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