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On Weak Well-posedness of the Nearest Point and Mutually Nearest Point Problems in Banach Spaces

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Acta Mathematica Sinica,English Series 2021年第8期37卷 1303-1312页

作者： Zi Hou ZHANG chun yan liu Yu ZHOU Jing ZHOU School of Mathematics Physics and Statistics Shanghai University of Engineering ScienceShanghai 201620P.R.China

Let G be a nonempty closed subset of a Banach space *** B(X)be the family of nonempty bounded closed subsets of X endowed with the Hausdorff distance and B_(G)(X)={A∈B(X):A∩G=φ},where the closure is taken in the metric space(B(X),H).For x∈X and F∈B_(G)(X),we denote the nearest point problem inf{||x-g||:g∈G}by min(x,G)and the mutually nearest point problem inf{||f-g||:f∈ F,g∈G}by min(F,G).In this paper,parallel to well-posedness of the problems min(a:,G)and mm(F,G)which are defined by De Blasi et al.,we further introduce the weak well-posedness of the problems min(x,G)and min(F,G).Under the assumption that the Banach space X has some geometric properties,we prove a series of results on weak well-posedness of min(x,G)and min(F,G).We also give two sufficient conditions such that two classes of subsets of X are almost Chebyshev sets.

关键词： The nearest point problem the mutually nearest point problem weak well-posedness relatively boundedly weakly compact set strict convexity dense Ga-subset

Synthesis, in vitro and in vivo biological evaluation of novel lappaconitine derivatives as potential anti-inflammatory agents

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Acta Pharmaceutica Sinica B 2020年第4期10卷 628-645页

作者： Lei Pang chun-yan liu Guo-Hua Gong Zhe-Shan Quan Key Laboratory of Natural Resources and Functional Molecules of the Changbai Mountain Affiliated Ministry of EducationCollege of PharmacyYanbian UniversityYanji 133002China Affiliated Hospital of Inner Mongolia University for Nationalities Tongliao 028000China

Lappaconitine(LA),a natural compound with a novel C18-diterpenoid alkaloid skeleton,displayed extensive biological *** research on LA is focused mainly on its anti-tumor and analgesic effects,and therefore we aimed to investigate its anti-inflammatory potential.A series of novel LA derivatives with various substituents on the 20-N position was designed and *** the initial screening of LA derivatives against NO production,all the target compounds,except compound E2,exhibited excellent inhibitory ability relative to that of ***,compound A4 exhibited the most potent inhibition with IC50 of 12.91 mmol/*** elementary structureeactivity relationships(SARs)of NO inhibitory activity indicated that replacement of the benzene ring with an electron donating group could improve the anti-inflammatory ***,compound A4 shows an anti-inflammatory mechanism by inhibiting NO,PGE2,and TNF-a generation via the suppression of NF-kB and MAPK signaling ***,compound A4 could exert a significant therapeutic effect on LPS-induced acute lung injury(ALI)in *** on the above research,we further investigated the preliminary pharmacokinetic property of A4 in ***,compound A4 could be a promising candidate for the development of anti-inflammatory agents in the future.

关键词： Lappaconitine Anti-inflammatory activity NF-kB MAPK Acute lung injury Pharmacokinetic study

The Aggregates in LB Films of Schiff base Aluminium (III) Complex

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Chinese Chemical Letters 2001年第3期12卷 271-272页

作者： Wei CAO Wei LIAN Yu Bai BAI chun yan liu Hui Bo SHAO Center for Intelligent Materials United Research(CIMUR) Department of ChemistryJilin UniversityChangchun 130023 Institute of Photographic Chemistry Chinese Academy of SciencesBeijing 100101 Department of Chemistry Capital Normal UniversityBeijing 100037

The surface pressure-area (pi -A) isotherm of Schiff base aluminium (III), tris (2-hydroxy-5-nitro-N-dodecyl-benzylideneaminato) aluminium (III) (denoted as Al(TAl2)(3)), on pure water subphase was investigated. The molecular area, 0.48 nm(2), is one-third of expected value that indicated the aggregation took place. The Langmuir-Blodgett (LB) films of Al(TAl2), was transferred and characterized. The AFM image confirmed the formation of aggregates.

关键词： Aluminium (III)-Schiff base complex LB films aggregate AFM image

Application of Current Hapten in the Production of Broad Specificity Antibodies Against Organophosphorus Pesticides

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Agricultural Sciences in China 2008年第11期7卷 1341-1347页

作者： liu Xian-jin yan chun-rong liu Yuan YU Xiang-yang ZHANG Cun-zheng Food Safety Research and Inspection Center Jiangsu Academy of Agricultural Sciences Nanjing 210014 P.R. China

Diethylphosphono acetic acid （DPA） was used as a current hapten to generate broad specificity polycolonal antibodies against a group of organophosphorus pesticides. Six New Zealand white rabbits were immunized with immunogens synthesized by the active ester method （AEM） or 1-ethyl-3-（3-dimethylaminopropyl）-carbodimide method （EDC）. The titers of antisera reached 25 600 by AEM and 6 400 by EDC, respectively. Polyclonal antibodies raised against DPA were screened and selected for the competitive indirect enzyme-linked immunosorbent assay （CI-ELISA）. A CI-ELISA for DPA was developed with a detection limit of 3.536 ng mL^-1and an I50 value of 0.182 μg mL^-1. The assay specificity was evaluated by obtaining competitive curves for several structurally related compounds as competitors. The antiserum showed high affinities to chlorpyrifos, diazinon, omethoate, parathion-ethyl and profenofos with I50 of 0.12, 0.15, 0.21, 0.88, 0.97 and 2.5 μg mL^-1, respectively. The results indicate that the assay could be a screening tool for quantitation and semiquantitation determination of the above former five organophosphorus pesticides.

关键词： organophosphorus pesticides broad specificity antibody enzyme-linked immunosorbent assay (ELISA)

An extremely promiscuous terpenoid synthase from the Lamiaceae plant Colquhounia coccinea var. mollis catalyzes the formation of sester-/di-/sesqui-/mono-terpenoids

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Plant Communications 2021年第5期2卷 106-119页

作者： De-Sen Li Juan Hua Shi-Hong Luo yan-chun liu Yue-Gui Chen Yi Ling Kai Guo yan liu Sheng-Hong Li State Key Laboratory of Phytochemistry and Plant Resources in West China and Yunnan Key Laboratory of Natural Medicinal Chemistry Kunming Institute of BotanyChinese Academy of SciencesKunming 650201P.R.China State Key Laboratory of Southwestern Chinese Medicine Resources and Innovative Institute of Chinese Medicine and Pharmacy Chengdu University of Traditional Chinese MedicineChengdu 611137P.R.China College of Bioscience and Biotechnology Shenyang Agricultural UniversityShengyang 110866P.R.China University of Chinese Academy of Sciences Beijing 100049P.R.China

Terpenoids are the largest class of natural products with complex structures and extensive bioactivities;their scaffolds are generated by diverse terpenoid synthases(TPSs)from a limited number of isoprenoid diphosphate *** TPSs play important roles in the evolution of terpenoid chemodiversity,but they remain largely ***,an extremely promiscuous terpenoid synthase(CcTPS1)of the TPS-b subfamily was cloned and functionally characterized from a leaf-specific transcriptome of the Lamiaceae plant Colquhounia coccinea ***1 is the first sester-/di-/sesqui-/mono-TPS identified from the plant kingdom,accepting C_(25)/C_(20)/C_(15)/C_(10) diphosphate substrates to generate a panel of sester-/di-/sesqui-/*** Escherichia coli expressing CcTPS1 produced three previously unreported terpenoids(two sesterterpenoids and a diterpenoid)with rare cyclohexanecontaining skeletons,along with four sesquiterpenoids and one *** structures were elucidated by extensive nuclear magnetic resonance *** benthamiana transiently expressing CcTPS1 also produced the diterpenoid and sesquiterpenoids,demonstrating the enzyme’s promiscuity in *** highly leaf-specific expression pattern combined with detectable terpenoid products in leaves of *** *** and *** expressing CcTPS1 suggested that CcTPS1 was mainly responsible for diterpenoid and sesquiterpenoid biosynthesis in ***1 expression and the terpenoid products could be induced by methyl jasmonate,suggesting their possible role in plant–environment ***1 was localized to the cytosol and may differ from mono-TPSs in subcellular compartmentalization and substrate *** findings will greatly aid our understanding of plant TPS evolution and terpenoid chemodiversity;they also highlight the enormous potential of transcriptome mining and heterologous expression for the exploration of unique enzym

关键词： terpenoid diversity terpenoid synthase promiscuous enzyme sester-/di-/sesqui-/mono-terpenoids Colquhounia coccinea var.mollis

Study on Quality Improvement Effect and Separate Character of Soybean Male Sterile (MS1) Recurrent Selection Population

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Agricultural Sciences in China 2007年第5期6卷 545-551页

作者： ZHAO Shuang-jin ZHANG Meng-chen JIANG chun-zhi yanG chun-yan liu Bing-qiang CUI Jue Institute of Food and Oil Crops Hebei Academy of Agricultural and Forestry Sciences~National Soybean Improvement Center ShijiazhuangSub-Center Shijiazhuang 050031 P.R.China

To solve the problem that soybean has narrow genetic base, we constructed a series of male sterile recurrent selection populations, and studied the effects of quality improvement and practical value. An LD-base population, which fits to our ecology type was constructed by 6 years＇ gene enrichment through the introduction of new genes from 23 local varieties and recurrent selection. The LD-base populations were then improved by making crosses with high protein and high oil genotypes. As a result we obtained a high protein sub-population （db） and a high oil sub-population （gy）, For the db sub-population, the protein content is 1.18% higher than the base population, 22.38% of the individuals contain 45% or more of protein, which is 10.99% higher than the base population. For the gy sub-population, oil content is 0.24% higher than the base population. Individuals with oil content of 20% or more are 11.05% higher than the base population. The quantitative characters such as flowering date, mature date, pod habit, and hilum color, etc., all showed wide range of separation, and the segregation ratio approached balance. The c.v. of branch number of ms1 recurrent population （72.8%） is higher than general cross-population （57.3%）, and the c.v. of 100 seed weight of ms1 （18.1%） is higher than general cross population （16.5%）, the coefficient of variation of plant height, pods per plant, and seeds per pod were not significantly different. It was demonstrated in this paper that the quality character of ms 1 male sterile recurrent selection population was improved by adding new genes. And the segregation of other characters widened, making the populations suitable for the objective of soybean breeding. In this paper, we also discussed the breeding method, key technology, and selection effect of soybean ms 1 population.

关键词： soybean recurrent selection population ms 1 gene quality improvement segregating characteristics

The inhibitory effects of NKX3.1 on IGF- 1R expression and its signalling pathway in human prostatic carcinoma PC3 cells

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Asian Journal of Andrology 2012年第3期14卷 493-498,I0009-I0010页

作者： Peng-Ju Zhang Xiao-yan Hu chun-yan liu Zhao-Bo Chen Na-Na Ni yang Yu Li-Na yang Zhao-Qin Huang Qing-Wei liu An-Li Jiang Institution of Biochemistry and Molecular Biology Medical School of Shandong UniversityJinan 250012China The People's Hospital of Zhangqiu City Zhangqiu 250200China Department of Radiology Shandong Provincial HospitalJinan 250021China

NKX3.1, which is a prostate-specific homeobox gene, plays an important role in prostate cancer and usually functions as a tumour suppressor gene. In this study, we investigated the inhibitory effect of NKX3,1 on insulin-like growth factor （IGF）- 1R expression and its downstream signalling pathway in PC3 cells, PC3 cells were stably transfected with NKX3.1 expression plasmid （pcDNA3.1-NKX3.1） or vector plasmid （pcDNA3.1＋）. The IGF-IR mRNA and protein expression levels were assessed in PC3-NKX3.1 transfectants by reverse transcriptase-polymerase chain reaction （RT-PCR） and Western blotting. The expression and activation of IGF-1/IGF-1R downstream signalling targets were examined by Western blotting and luciferase reporter assay. The cells were subsequently treated with relevant concentrations of IGF-1. The effect of IGF-1 on cell growth was examined by 3-（4,5）-dimethylthiahiazo（-z-yl）-3, 5-diphenytetrazoliumromide （MTT） assay and flow cytometry analysis. A significant suppression of IGF-1R mRNA and protein expression was observed after forced expression of NKX3.1 in PC3 cells. Correspondingly, the forced expression of NKX3.1 decreased IGF-l-induced phosphorylation of extracellular signal-regulated kinase 1/2 （ERK1/2） and protein kinase B （AKT） and activation of the Elk-1 transcription factor and downregulated the expression of the downstream target genes c-fos and cyclin D1. Furthermore, the forced expression of NKX3.1 inhibited IGF-l-induced cell growth. In conclusion, NKX3.1 could downregulate IGF-1R expression and could inhibit IGF-1R-mediated mitogen-activated protein kinase （MAPK）/ERK and AKT signalling pathways, which might partially leads to the inhibition of IGF-l-induced cell growth. This study provides new insights into the molecular mechanisms that NKX3,1 exerts against prostate cancer and ultimately expands the scope of alternative approaches in advanced prostate cancer therapy.

关键词： IGF-I IGF-1R NKX3.1 prostate cancer

Nickel-Catalyzed Cross-Electrophile Vinyl–Vinyl Coupling:An Approach to Structurally Versatile Dienylboronates

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CCS Chemistry 2022年第3期4卷 864-871页

作者： Guang-Li Xu chun-yan liu Xiaobo Pang Xue-Yuan liu Xing-Zhong Shu State Key Laboratory of Applied Organic Chemistry(SKLAOC) College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000

Cross C–C bond formation of two vinyl electrophiles is a long-standing challenge in synthetic ***,we report a nickel-catalyzed reductive vinyl–vinyl coupling between vinyl triflates and boron-substituted vinyl *** new protocol offers facile access to dienylboronates with high structural complexity and molecular *** reaction proceeds with a broad substrate scope under very mild *** synthetic utility of the method is highlighted by its gram-scale reaction,modification of complex molecules,and diverse transformation of the products.

关键词： nickel boron dienes cross-coupling reductive coupling

Numerical simulation of microstructure and microporosity morphology in directional solidification of aluminum-copper alloys:Effect of copper content and withdrawal rate

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China Foundry 2025年第1期22卷 33-44页

作者： Wei Yuan Hai-dong Zhao Xu Shen chun Zou Yuan liu Qing-yan Xu National Engineering Research Center of Near-Net-Shape Forming for Metallic Materials South China University of TechnologyGuangzhou 510640China Key Laboratory for Advanced Materials Processing Technology(Ministry of Education) Tsinghua UniversityBeijing 100084China

Microporosity formed in the solidification process of Al alloys is detrimental to the alloy properties.A two-dimensional cellular automaton(CA)model was developed to simulate the microstructure and microporosity formation in Al-Cu alloys,considering variations in Cu content and solidification *** results indicate that the Cu content primarily influences the growth of *** validate the model,directional solidification experiments were conducted on Al-Cu alloys with varing Cu contents and withdrawal *** experimental results of dendrites and microporosity characteristics agree well with the predictions from the developed model,thus confirming the validity of the *** alloy’s liquidus temperature,dendrite morphology,and hydrogen saturation solubility arising from different Cu contents have significant effects on microporosity *** withdrawal rate primarily affects the nucleation of hydrogen microporosity by altering cooling rates and dendritic growth rates,resulting in different microporosity characteristics.

关键词： microporosity dendrites cellular automaton Al-Cu alloys directional solidification