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New halimane and clerodane diterpenoids from Croton cnidophyllus

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Natural Products and Bioprospecting 2023年第1期13卷 537-545页

作者： Xun wei Jia-Luo hua.g hua-hua.gao Fang-Yu Yuan gui-hua Tang sheng Yin School of Pharmaceutical Sciences Sun Yat-Sen UniversityGuangzhou 510006People’s Republic of China

Three new halimane furanoditerpenoids(1-3)and three new clerodane furanoditerpenoids(4-6),along with seven known terpenoids including four pimarane diterpenoids(7-10)and three norisoprenoids(11-13)were isolated from the 95%EtOH extracts of the plants of Croton *** 2D structures including absolute configuration of new furanoditerpenoids(1-6)were elucidated by analysis of their HRMS and NMR data as well as comparison of experi-mental and calculated ECD *** revealed that two compounds(8 and 9)possessed certain inhibitory effects against NO production stimulated by LPS,with IC_(50) values of 19.00±1.76 and 21.61±1.11μM,respectively.

关键词： Euphorbiaceae Croton cnidophyllus Furanoditerpenoids Anti-inflammatory activity

Embolic Effects of Bletilla striata Microspheres in Renal Artery and Transplanted VX2 Liver Tumor Model in Rabbits

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Chinese Journal of Integrative Medicine 2019年第6期25卷 431-438页

作者： LUO Shi-hua SONg Song-lin ZHENg Chuan-sheng LI wei-yong WANg Yong XIA Xiang-wen FENg gan-sheng Department of Radiology Union Hospital Tongji Medical College Huazh ong University of Science and Tech no logy Wuhan (430022) China Department of Pharmacy Union Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan (430022) China

Objective: To evaluate the characteristics of Bletilla striata microspheres(BSMs) and its effects as an embolic agent in a rabbit model. Methods: BSMs were prepared with an emulsi?cation-cool condensation-chemical cross-linking method. The characteristics of BSMs in vitro were observed. Embolization experiments were performed in renal artery of rabbit and in a rabbit liver VX2 carcinoma model. Seventy-two New Zealand rabbits were divided into 2 groups, and the right renal artery was embolized with BSMs(200 μm in diameter) in the experimental group and with polyvinyl alcohol(PVA) of the same size in the control group. The pathological findings were examined with hematoxylin-eosin and Masson stainings. Liver and renal functions were tested before and after ***2 tumor was transplanted in 15 New Zealand rabbits, which were randomly divided into 3 groups(n=5). group A were treated with saline, group B with a mixture of doxorubicin and lipiodol, and group C with hepatic arterial infusion of BSMs(200 μm in diameter). Tumor growth rate was evaluated by magnetic resonance imaging ***-related factors(bax, bcl-2) and tumor vascular endothelial cell growth factor(VEgF) were evaluated through immunohistochemical staining. Results: The characteristics of BSMs in vitro were in full compliance with the requirements for use in interventional procedures. In the renal artery embolization experiment, after BSMs intervention, it was more dif?cult to form collateral circulation than that with PVAs, and the kidney manifested atrophy and calci?cation. There were no signi?cant difference of liver and renal functions in rabbits between groups. In the liver VX2 carcinoma embolization experiment, compared with group A, the growth rate of VX2 liver tumor and Bcl-2 levels was reduced, while apoptosis index, Bax, and VEgF were increased in group B(Pgni?cant difference between groups B and C(P>0.05). Conclusions: The characteristics of BSMs in vitro a

关键词： Bletilla striata Chinese medicine microsphere characteristic embolization

A COUPLINg MODEL OF WATER FLOWS AND gAS FLOWS IN EXHAUSTED gAS BUBBLE ON MISSILE LAUNCHED UNDERWATER

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Journal of Hydrodynamics 2007年第4期19卷 403-411页

作者： CHENg Yong-sheng LIU hua Department of Engineering Mechanics Shanghai Jiaotong University Shanghai 200030 China

The gas and water flows during an underwater missile launch are numerically studied. For the gas flow, the explicit difference scheme of Non-oscillation and Non-free-parameter Dissipation (NND) is utilized to solve the Euler equations for compressible fluids in the body-fitted coordinates. For the water flow, the Hess-Smith method is employed to solve the Laplace equation for the velocity potential of irrotational water flows based on the potential theory and the boundary element method. The hybrid Eulerian-Lagrangian formulation for the free boundary conditions is used to compute the changes of the free surface of the exhausted gas bubble in time stepping. On the free surface of the exhausted gas bubble, the matched conditions of both the normal velocities and pressures are satisfied. From the numerical simulation, it is found that the exhausted gas bubble grows more rapidly in the axial direction than in the radial direction and the bubble will shrink at its "neck" finally. Numerical results of the movement of the shock wave and the distribution of the Mach number and the gas pressure within the bubble were presented, which reveals that at some time, the gas flow in the Laval nozzle is subsonic and the gas pressure in the nozzle is very high. Influences of various initial missile velocities and chamber total pressures and water depths on both the time interval when the gas flow in the nozzle is subsonic and the peak of the gas pressure at the nozzle end were discussed. It was suggested that a reasonable adjustment of the chamber total pressure can improve the performance of the engine during the underwater launch of missiles.

关键词： exhausted gas bubble Laval nozzle missile launched underwater shock wave gas jet

Parameter identification and global sensitivity analysis of Xin'anjiang model using meta-modeling approach

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Water Science and Engineering 2013年第1期6卷 1-17页

作者： Xiao-meng SONg Fan-zhe KONg Che-sheng ZHAN Ji-wei HAN Xin-hua ZHANg Hydrology and Water Resources Department Nanjing Hydraulic Research Institute School of Resource and Earth Science China University of Mining and Technology Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University

Parameter identification, model calibration, and uncertainty quantification are important steps in the model-building process, and are necessary for obtaining credible results and valuable information. Sensitivity analysis of hydrological model is a key step in model uncertainty quantification, which can identify the dominant parameters, reduce the model calibration uncertainty, and enhance the model optimization efficiency. There are, however, some shortcomings in classical approaches, including the long duration of time and high computation cost required to quantitatively assess the sensitivity of a multiple-parameter hydrological model. For this reason, a two-step statistical evaluation framework using global techniques is presented. It is based on （1） a screening method （Morris） for qualitative ranking of parameters, and （2） a variance-based method integrated with a meta-model for quantitative sensitivity analysis, i.e., the Sobol method integrated with the response surface model （RSMSobol）. First, the Morris screening method was used to qualitatively identify the parameters＇ sensitivity, and then ten parameters were selected to quantify the sensitivity indices. Subsequently, the RSMSobol method was used to quantify the sensitivity, i.e., the first-order and total sensitivity indices based on the response surface model （RSM） were calculated. The RSMSobol method can not only quantify the sensitivity, but also reduce the computational cost, with good accuracy compared to the classical approaches. This approach will be effective and reliable in the global sensitivity analysis of a complex large-scale distributed hydrological model.

关键词： Xin'anjiang model," global sensitivity analysis parameter identification meta-modeling approach," response surface model

Determination of the genetic diversity of vegetable soybean [glycine max(L.) Merr.] using EST-SSR markers

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2013年第4期14卷 279-288页

作者： gu-wen ZHANg sheng-chun XU wei-hua MAO Qi-zan HU Ya-ming gONg Institute of Vegetable Research Zhejiang Academy of Agricultural Sciences Center of Analysis and Measurement Zhejiang University

The development of expressed sequence tag-derived simple sequence repeats(EST-SSRs) provided a useful tool for investigating plant genetic *** the present study,22 polymorphic EST-SSRs from grain soybean were identified and used to assess the genetic diversity in 48 vegetable soybean *** the 22 EST-SSR loci,tri-nucleotides were the most abundant repeats,accounting for 50.00% of the total *** was the most common motif among tri-nucleotide repeats,with a frequency of 18.18%.Polymorphic analysis identified a total of 71 alleles,with an average of 3.23 per *** polymorphism information content(PIC) values ranged from 0.144 to 0.630,with a mean of *** heterozygosity(H o) values varied from 0.0196 to 1.0000,with an average of 0.6092,while the expected heterozygosity(H e) values ranged from 0.1502 to 0.6840,with a mean value of *** coordinate analysis and phylogenetic tree analysis indicated that the accessions could be assigned to different groups based to a large extent on their geographic distribution,and most accessions from China were clustered into the same *** results suggest that Chinese vegetable soybean accessions have a narrow genetic *** results of this study indicate that EST-SSRs from grain soybean have high transferability to vegetable soybean,and that these new markers would be helpful in taxonomy,molecular breeding,and comparative mapping studies of vegetable soybean in the future.

关键词： Expressed sequence tag(EST) Simple sequence repeat(SSR) genetic diversity Microsatellites Vegetable soybean

Quantitative Determination of Cr in Ink by Laser-induced Breakdown Spectroscopy（LIBS） Using ZnO as Adsorbent

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Chemical Research in Chinese Universities 2015年第6期31卷 909-913页

作者： wei Jiao ZHANg Tianlong DONg Juan sheng Liwen TANg Hongsheng YANg Xiaofeng LI hua Institute of Analytical Northwest University Xi 'an 710069 P. R. China College of Chemistry & Materials Science Northwest University Xi 'an 710069 P. R. China College of Chemistry and Chemical Engineering Xi 'an Shiyou University Xi 'an 710065 P. R. China

Laser-induced breakdown speetroscopy（LIBS） technique was applied to detecting chromium in ink with ZnO as adsorbent, and the LIBS spectra were preproeessed by wavelet denoising. The laser energy and delay time were optimized depending on the signal-to-noise ratio（SNR） and intensity of three analysis atomic lines（Cr 425.43 nm, Cr 427.48 nm and Cr 428.97 nm）. Compared with other analysis lines, atomic line of Cr 427.48 nm was selected as the analysis line for the quantitative analysis of Cr in ink as the calibration curve of it showed a better linear rela- tionship （correlation coefficient R^2=0.9778）, and the relative error of Cr in the measured ink was 52.96%. Since the single spectral line used for calibration curve method is often influenced by matrix effect and other factors, partial least squares regression（PLS） as multivariate calibration method has been applied to predicting the concentration of Cr in ink, and the relative error of Cr in the measured ink was 10.48%. The result obtained from the PLS method was better than that from the calibration curve when comparing the relative error, demonstrating that, based on adsorbent, LIBS combined with PLS provides an effective, practical and convenient technique for the determination of trace element in aqueous solution.

关键词： Laser-induced breakdown spectroscopy Zinc oxide Partial least square Chromium Ink

Putrescine Plays a Positive Role in Salt-Tolerance Mechanisms by Reducing Oxidative Damage in Roots of Vegetable Soybean

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Journal of Integrative Agriculture 2014年第2期13卷 349-357页

作者： ZHANg gu-wen XU sheng-chun HU Qi-zan MAO wei-hua.gONg Ya-ming Institute of Vegetable Zhejiang Academy of Agricultural Sciences Center of Analysis and Measurement Zhejiang University

Polyamines play important roles in plant tolerance to environmental stress. With the aim of investigating the possible involvement of putrescine （Put） in salt-tolerance mechanisms in vegetable soybean roots, exogenous Put （10 mmol L＂） and its biosynthetic inhibitor D-arginine （D-Arg）（0.5 mmol L-1） were added to nutrient solution when vegetable soybean （glycine max L. cv. Huning 95-1） seedlings were exposed to 100 mmol L^-11 sodium chloride （NaCl）. The results showed that Put ameliorated but D-Arg aggravated the detrimental effects of NaCl on plant growth and biomass production. Under NaCl stress, levels of free, soluble conjugated and insoluble bound types of Put in roots of vegetable soybean were reduced, whereas those of free, soluble conjugated, and insoluble bound types of spermidine （Spd） and spermine （Spm） were increased. Exogenous Put eliminated the decrease in Put but promoted the increase of Spd and Spm. However, these changes could be reversed by D-Arg. Under NaCl stress, activities of arginine decarboxylase （ADC）, S-adenosylmethionine decarboxylase （SAMDC）, diamine oxidase （DAO）, and polyamine oxidase （PAO） were induced, with exogenous Put promoting and D-Arg reversing these changes. Furthermore, NaCl stress decreased activities of antioxidant enzymes. Exogenous Put alleviated but D-Arg exaggerated these effects of NaCl stress, resulting in the same changes in membrane damage and reactive oxygen species （ROS） production. These results indicated that Put plays a positive role in vegetable soybean roots by activating antioxidant enzymes and thereby attenuating oxidative damage.

关键词： NaCl stress oxidative damage putrescine salt-tolerance vegetable soybean

Soil Organic Carbon Transformation and Related Properties in Urban Soil Under Impervious Surfaces

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Pedosphere 2014年第1期24卷 56-64页

作者： wei Zong-Qiang WU Shao-hua ZHOU sheng-Lu LI Jing-Tao ZHAO Qi-guo School of geographic and Oceanographic Science Nanjing University Institute of Soil Science Chinese Academy of Sciences

Installation of impervious surface in urban area prevents the exchange of material and energy between soil and other environmental counterparts,thereby resulting in negative effects on soil function and urban *** samples were collected at 0-20cm depth in Nanjing City,China,in which seven sites were selected for urban open soils,and fourteen sites with similar parent material were selected for the impervious-covered soils,to examine the effect of impervious surface on soil properties and microbial activities,and to determine the most important soil properties associated with soil organic carbon(SOC)transformation in the urban soils covered by impervious *** organic carbon and water-soluble organic carbon(WSOC)concentrations,potential carbon(C)and nitrogen(N)mineralization rates,basal respiration,and physicochemical properties with respect to C transformation were *** of impervious surface severely affected soil physicochemical properties and microbial activities,e.g.,it significantly decreased total N contents,potential C mineralization and basal respiration rate(Pganic carbon in the sealed soils at 0-20 cm was 2.35 kg m^(-2),which was significantly lower than the value of 4.52 kg m^(-2)in the open soils(Pg SOC transformation in the impervious-covered soil,and it was highly correlated with total N content and potential C mineralization *** findings demonstrate that installation of impervious surface in urban area,which will result in decreases of SOC and total N concentrations and soil microbial activities,has certain negative consequences for soil fertility and long-term storage of SOC.

关键词： carbon mineralization microbial activity soil fertility soil sealing water-soluble organic carbon

Existence of the Eigenvalues for the Cone Degenerate p-Laplacian

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Chinese Annals of Mathematics,Series B 2021年第2期42卷 217-236页

作者： hua CHEN Yawei wei School of Mathematics and Statistics Wuhan UniversityWuhan 430072China School of Mathematical Sciences and LPMC Nankai UniversityTianjin 300071China

The present paper is concerned with the eigenvalue problem for cone degenerate p-Laplacian. First the authors introduce the corresponding weighted Sobolev spaces with important inequalities and embedding properties. Then by adapting LusternikSchnirelman theory, they prove the existence of infinity many eigenvalues and eigenfunctions. Finally, the asymptotic behavior of the eigenvalues is given.

关键词： Quasi-linear Degenerate operator Variational methods