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Topological Structure of Non-wandering Set of a Graph Map

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Acta Mathematica Sinica,English Series 2005年第4期21卷 873-880页

作者： Rong bao gu Tai Xiang SUN Ting Ting ZHENG School of Finance Nanjing University of Finance and Economics Nanjing 210046 P. R. China Department of Mathematics Guangxi University Nanning 530004 P. R. China Department of Mathematics University of Science and Technology of China Department of Mathematics Anhui University Hefei 230039 P. R. China

Let G be a graph （i.e., a finite one-dimensional polyhedron） and f ： G → G be a continuous map. In this paper, we show that every isolated recurrent point of f is an isolated non-wandering point; every accumulation point of the set of non-wandering points of f with infinite orbit is a two-order accumulation point of the set of recurrent points of f; the derived set of an ω-limit set of f is equal to the derived set of an the set of recurrent points of f; and the two-order derived set of non-wandering set of f is equal to the two-order derived set of the set of recurrent points of f.

关键词： Graph map Recurrent point ω-limit point Non-wandering set Derived set

Insight into the green route to dimethyl succinate by direct esterification of bio-based disodium succinate using CO_(2)and CH_(3)OH

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Chinese Journal of Chemical Engineering 2023年第12期64卷 188-195页

作者： Yu-Gao Wang Xiao-Chen Han bao gu Hua-Shuai Wu Jun Shen School of Chemical Engineering and Technology Taiyuan University of TechnologyTaiyuan 030024China

The fermentation for succinic acid production outperforms other methods by low energy consumption and environmental benignity,with the resulting products mainly as disodium succinate(DSA).By directly esterifying DSA using CO_(2) and CH3OH,it is expected to avoid the use of inorganic *** high-resolution mass spectrometry analysis and theoretical calculation,this study establishes that the reaction consists of three steps,i.e.,first forming 3-carboxypropanoate,then monomethyl succinate(MMS),and finally dimethyl succinate(DMS).A detailed kinetic analysis is further performed,the results demonstrate that the transformation of DSA to MMS is regarded to be a second-order reaction for reactant DSA,while the transformation of MMS to DMS is a first-order reaction for reactant *** activation energy for the generation of MMS from DSA is 37.15 kJ·mol^(-1),and that for the generation of DMS from MMS is 85.80 kJ·mol^(-1),indicating the latter one is the rate-determining step.

关键词： Succinate Carbon dioxide Direct esterification Reaction mechanism Reaction kinetics Kinetic modeling

Metastasis to scrotal skin as the initial manifestation in a patient with rectal adenocarcinoma, a rare case report and literature review

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Asian Journal of Andrology 2016年第3期18卷 492-493页

作者： Gang Wu bao-Jun gu Kent L Nastiuk Jun gu Deng-Long Wu Department of Urology Tongji Hospital Tongji University School of MedicineShanghai China Department of Urology Shanghai 6th People's Hospital ShanghaiJiao Tong University Shanghai China Department of Pathology and Laboratory Medicine University of Rochester Rochester New York USA Department of Pathology Tongji Hospital Tongji University School of Medicine Shanghai China.

Dear Editor, We present here a rare case of rectal adenocarcinoma metastasized to scrotum skin that was detected in a 36-year-old man. In addition, we have reviewed the Chinese and English literature for reports of i... 详细信息

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Influence of Simulated Outside-Reactor Irradiation on Anticorrosion Property of Austenitic Stainless Steel

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Journal of Iron and Steel Research International 2006年第2期13卷 45-48页

作者： gu bao-shan JI Xiao-chun ZHANG Qi-fu LIU Jian-hua School of Materials Science and Engineering Beijing University of Aeronautics and Astronautics Beijing 100083 China New Metallurgy Group Co Ltd Central Iron and Steel Research Institute Beijing 100081 China

The influence of γ-ray irradiation on the properties of inside-reactor stainless steel structures was studied by simulating the working condition of pressurized water reactor （PWR） first circuit and the outside-reactor y-ray irradiation. The result shows that the simulated outside-reactor irradiation （irradiation dose 4. 4 ）〈 104 Gy） has no influence on anticorrosion properties of solutionized SUS304 austenitic stainless steel, including intergranular corrosion （IC） and stress corrosion cracking （SCC）. Anticorrosion properties （IC, SCC） of sensitized SUS304 austenitic stainless steel are reduced by simulated outside-reactor irradiation. The longer the sensitized time is, the more obvious the influence is.

关键词： simulated irradiation IC SCC stainless steel antieorrosion

Ethylene Evolution Changes in Tilted Fraxinus mandshurica Rupr. var. japonica *** in Relation to Tension Wood Formation

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Journal of Integrative Plant Biology 2009年第7期51卷 707-713页

作者： Sha Jiang Ke Xu Na Zhao Shu-Xin Zheng Yan-Ping Ren Yu-bao Gao Song gu College of Life Sciences Nankai University Tianjin 300071 China

The effects of ethylene on tension wood formation were studied in 3-year-old Fraxinus mandshurica Rupr. var. japonica Maxim. seedlings in two separate experiments. In experiment 1, ethylene evolution of buds and stems was measured using gas chromatography after 0, 2, 4, 7, 14, and 21 d of treatment; in experiment 2, both aminoethoxyvinylglycine （AVG） and AgNO3 were applied to the horizontally-placed stems, and the cell numbers on sites of applications were measured after 40 d. Ethylene evolution from buds was found to be much greater in tilted seedlings than in upright ones. The cell numbers of wood fibers in shoots and 1-year-old stems were reduced in treatments with 12.5×10^-7μmol/L AVG, 12.5×10^-8μmol/L AVG, and 11.8×10^-8μmol/Lmol/L AgNO3; whereas the horizontal and vertical diameters were reduced by treatment of 12.5×10^-7μmol/L AVG. Ethylene evolutions of shoots and 1-year-old stems were inhibited greatly in comparison with the control by applying 12.5×10^-7μmol/L AVG. The formation of a gelatinous layer of wood fibers was affected by neither AVG nor AgNO3 application. These results suggest that ethylene regulates the quantity of wood production, but does not affect G-layer formation in F. mandshurica Rupr. *** Maxim. seedlings.

关键词： ethylene evolution Fraxinus mandshurica inhibitors tension wood formation

Different responses of two Mosla species to potassium limitation in relation to acid rain deposition

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2009年第8期10卷 563-571页

作者： Meng WANG bao-jing gu Ying GE Zhen LIU De-an JIANG Scott X. CHANG Jie CHANG College of Life Sciences Zhejiang University Hangzhou 310058 China Department of Renewable Resources University of Alberta Edmonton Alberta T6G 2E3 Canada

The increasingly serious problem of acid rain is leading to increased potassium （K） loss from soils, and in our field investigation, we found that even congenerically relative Mosla species show different tolerance to K-deficiency. A hydroponic study was conducted on the growth of two Mosla species and their morphological, physiological and stoichiometric traits in response to limited （0.35 mmol K/L）, normal （3.25 mmol K/L） and excessive （6.50 mmol K/L） K concentrations. Mosla hangchowensis is an endangered plant, whereas Mosla dianthera a widespread weed. In the case of M. hangchowensis, in comparison with normal K concentration, K-limitation induced a significant reduction in net photosynthetic rate （Pn）, soluble protein content, and superoxide dismutase （SOD） actix, ity, but an increase in malondialdehyde （MDA） concentration. However, leaf mass ratio （LMR） and root mass ratio （RMR） were changed little by K-limitation. In contrast, for M. dianthera, K-limitation had little effect on Pn, soluble protein content, SOD activity, and MDA concentration, but increased LMR and RMR. Critical values of N （nitrogen）：K and K：P （phosphorus） ratios in the shoots indicated that limitation in acquiring K occurred under K-limited conditions for M. hangchowensis but not for M. dianthera. We found that low K content in natural habitats was a restrictive factor in the growth and distribution of M.. hangchowensis, and soil K-deficiency caused by acid rain worsened the situation of M. hangchowensis, while M. dianthera could well acclimate to the increasing K-deficiency. We suggest that controlling the acid rain and applying K fertilizers may be an effective way to rescue the endangered M. hangchowensis.

关键词： Ecophysiological response Endangered species Morphological plasticity Mosla species Weed

Helicobacter pylori and portal hypertensive gastropathy

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Hepatobiliary & Pancreatic Diseases International 2018年第6期17卷 578-580页

作者： Ji-Ke Hu Xue-Mei Li bao-Hong gu Fan Zhang Yu-Min Li Hao Chen The Second Clinical Medical College of Lanzhou University Lanzhou 730000China The Key Laboratory of the Digestive System Tumors of Gansu Province Second Hospital of Lanzhou UniversityLanzhou 730000China The Department of Tumor Surgery Second Hospital of Lanzhou UniversityLanzhou 730000China

To the Editor:H. pylori lives in the gastric epithelial cells, sometimes in gastric *** of H. pylori can be influenced by the status of the gastric mucosa is still unknown. Portal hypertensive gastropathy (PHG) is a blood drainage obstructive disease. In this pathologic environment, gastric mucosa may be further impaired when patients are infected with H. pylori. The role of H. pylori in the pathogenesis of PHG and

关键词： PHG In Helicobacter pylori and portal hypertensive gastropathy

Construction of an efficient genomic editing system with CRISPR/Cas9 in the vector mosquito Aedes albopictus

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Insect Science 2019年第6期26卷 1045-1054页

作者： Tong Liu Wen-Qiang Yang Yu-gu Xie Pei-Wen Liu Li-Hua Xie Feng Lin Chen-Ying Li Jin-bao gu Kun Wu gui-Yun Yan Xiao-guang Chen Department of Pathogen Biology Guangdong Provincial Key Laboratory of Tropical Disease Research School of Public Health Southern Medical University Guangzhou China

Aedes (Stegomyia) albopictus, also known as the Asian tiger mosquito, is a mosquito which originated in Asia. In recent years, it has become increasingly rampant throughout the world. This mosquito can transmit several arboviruses, including dengue, Zika and chikungunya viruses, and is considered a public health threat. Despite the urgent need of genome engineering to analyze specific gene functions, progress in genetical manipulation of Ae. albopictus has been slow due to a lack of efficient methods and genetic markers. In the present study, we established targeted disruptions in two genes, kynurenine hydroxylase (kh) and dopachrome conversion enzyme (yellow), to analyze the feasibility of generating visible phenotypes with genome editing by the clustered regularly interspaced short palindromic repeats (CRISPR)/ CRISPR-associated protein 9 (Cas9) system in Ae. albopictus. Following Cas9 single guide RNA ribonucleoprotein injection into the posterior end of pre-blastoderm embryos, 30%-50% of fertile survivors produced alleles that failed to complement existing kh and yellow mutations. Complete eye and body pigmentation defects were readily observed in GI pupae and adults, indicating successful generation of highly heritable mutations. We conclude that the CRISPR/Cas9-mediated gene editing system can be used mAe. albopictus and that it can be adopted as an efficient tool for genome-scale analysis and biological study.

关键词： Aedes albopictus CRISPR/Cas9 dopachrome conversion enzyme (yellow) gene editing kynurenine hydroxylase (kh)

Identifying species-specific subsequences in bacteria transcription terminators-A machine learning approach

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Journal of Biomedical Science and Engineering 2009年第3期2卷 184-189页

作者： bao-Hua gu Yi Sun School of Computing Science Simon Fraser University 8888 University Drive Burnaby BC Canada.

Transcription Terminators (TTs) play an impor-tant role in bacterial RNA transcription. Some bacteria are known to have Species-Specific Subsequences (SSS) in their TTs, which are be-lieved containing useful clues to bacterial evolu-tion. The SSS can be identified using biological methods which, however, tend to be costly and time-consuming due to the vast number of sub-sequences to experiment on. In this paper, we study the problem from a computational per-spective and propose a computing method to identify the SSS. Given DNA sequences of a tar-get species, some of which are known to contain a TT while others not, our method uses machine learning techniques and is done in three steps. First, we find all frequent subsequences from the given sequences, and show that this can be effi-ciently done using generalized suffix trees. Sec-ond, we use these subsequences as features to characterize the original DNA sequences and train a classification model using Support Vector Machines (SVM), one of the currently most effec-tive machine learning techniques. Using the pa-rameters of the resulting SVM model, we define a measure called subsequence specificity to rank the frequent subsequences, and output the one with the highest rank as the SSS. Our experi-ments show that the SSS found by the proposed method are very close to those determined by biological experiments. This suggests that our method, though purely computational, can help efficiently locate the SSS by effectively narrowing down the search space.

关键词： bacteria transcription