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Estimation of vegetation biophysical parameters by remote sensing using radial basis function neural network

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第6期8卷 883-895页

作者： YANG Xiao-hua HUANG Jing-feng WANG jian-wen WANG Xiu-zhen LIU Zhan-yu Institute of Agricultural Remote Sensing ＆ Information Application Zhejiang University Hangzhou 310029 China Key Laboratory of Agricultural Remote Sensing ＆ Information System Hangzhou 310029 China Communication Training Base of General Staff Headquarters Beijing 102400 China Zhejiang Meteorological Institute Hangzhou 310004 China

Hyperspectral reflectance (350~2500 nm) data were recorded at two different sites of rice in two experiment fields including two cultivars, and three levels of nitrogen (N) application. Twenty-five Vegetation Indices (VIs) were used to predict the rice agronomic parameters including Leaf Area Index (LAI, m2 green leaf/m2 soil) and Green Leaf Chlorophyll Density (GLCD, mg chlorophyll/m2 soil) by the traditional regression models and Radial Basis Function Neural Network (RBF). RBF emerged as a variant of Artificial Neural Networks (ANNs) in the late 1980’s. A large variety of training algorithms has been tested for training RBF networks. In this study, Original RBF (ORBF), Gradient Descent RBF (GDRBF), and Generalized Regression Neural Network (GRNN) were employed. Results showed that green waveband Normalized Difference Vegetation Index (NDVIgreen) and TCARI/OSAVI have the best prediction power for LAI by exponent model and ORBF respectively, and that TCARI/OSAVI has the best prediction power for GLCD by exponent model and GDRBF. The best performances of RBF are compared with the traditional models, showing that the relationship between VIs and agronomic variables are further improved when RBF is used. Compared with the best traditional models, ORBF using TCARI/OSAVI improves the prediction power for LAI by lowering the Root Mean Square Error (RMSE) for 0.1119, and GDRBF using TCARI/OSAVI improves the prediction power for GLCD by lowering the RMSE for 26.7853. It is concluded that RBF provides a useful exploratory and predictive tool when applied to the sensitive VIs.

关键词： Artificial neural network (ANN) Radial basis function (RBF) Remote sensing Rice Vegetation index (VI)

An Unusual(3,11)-Connected Network Constructed by Tri-nuclear Lanthanide Building Units and Mixed Ligands

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Chinese Journal of Structural Chemistry 2020年第1期39卷 104-109,4页

作者： JIN Cong-Cong CHEN Zi-Bin CHENG jian-wen Key Laboratory of the Ministry of Education for Advanced Catalysis Materials Institute of Physical ChemistryZhejiang Normal UniversityJinhuaZhejiang 321004China

Under hydrothermal conditions,a new lanthanide coordination polymer,[Er3(oba)4(na)]n(1,oba=4,4?-oxybis(benzoate),na=nicotinic acid)has been *** 1 shows a 3D framework by incorporating tri-nuclear[Er3(COO)6]unit and the mixed ligands of oba2-and na-.It is interesting that decarboxylation occurred in the ortho position and 2,3-pyridinedicarboxylic acid was partially transformed into na under hydrothermal *** 1 can be reduced into a(3,11)-connected net and displays weak second-harmonic generation ***,the PXRD,TGA and IR spectra were also studied.

关键词： lanthanide coordination polymer mixed ligands second-harmonic generation

Assessment of mouse BMMNC DNA damage with a two-tailed comet assay after X-ray and carbon ion total body irradiation

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Nuclear Science and Techniques 2018年第6期29卷 1-8页

作者： Fang Liu Zhuan-Zi Wang wen-jian Li Wei Wei Bing-Rong Dang Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000 China University of Chinese Academy of Sciences Beijing 100049China

The two-tailed comet assay(2T-comet assay) is a method for simultaneously evaluating DNA single-strand breaks(SSBs) and double-strand breaks(DSBs). In the present study, the endonuclease DNase I and hydrogen peroxide were used to induce DSBs and SSBs in bone marrow mononuclear cells(BMMNCs) from mice, and the damaged DNAs were assessed with a 2T-comet assay. The results demonstrated that this method can detect and discriminate between BMMNC DNA SSBs and DSBs simultaneously. Using this method, we studied DNA damage in BMMNCs from female BALB/c mice after total body irradiation with X-rays and carbon ions. The results indicated that these two types of radiation induced serious DNA damage in BMMNCs in a dose-dependent *** DNA damage induced by carbon ions was more severe than that induced by X-rays at the same dose, and a high dose of carbon ion radiation was more likely to cause death in mice. The DSBs and SSBs induced by X-rays were the highest on the 3rd day post-IR. For carbon ion radiation,DSBs were the most serious on the 3rd day, while SSBs were more obvious on the 3rd day and 13th day *** ratio of DSBs/SSBs was clearly related to the different types of radiation.

关键词： DNA 碳离子损坏彗星尾巴身体金鼠标

A new isoflavane from processed Astragalus membranaceus

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Chinese Chemical Letters 2007年第9期18卷 1092-1094页

作者： Wei Liu Jing Chen wen jian Zuo Xian Li Jin Hui Wang Shengyang Pharmaceutical University Shenyang 10016 China

A new isoflavane named astraganoside, together with five known compounds had been isolated from the processed Astragralus membranaceus. The structure of the novel compound was elucidated as (3R, 4R)-3-(2-hydroxy-3,4-dimethoxyphenyl)chroman-4,7-diol-7-O-β-d-glucopyranoside (1) based on spectroscopic methods including UV, IR, ESI-MS, 1D NMR and 2D NMR techniques.

关键词： Processed Astragalus membranaceus Isoflavane Astraganoside

Is endoscopic mucosal resection-precutting superior to conventional methods for removing sessile colorectal polyps?

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World Journal of Gastrointestinal Surgery 2023年第8期15卷 1838-1840页

作者： Qun-Ying Yang Qian Zhao jian-wen Hu Department of Gastroenterology Dongyang People's HospitalDongyang 322100Zhejiang ProvinceChina

We reviewed a study that reported a comparative analysis of the effects of endoscopic mucosal resection(EMR)precutting and conventional EMR for removing non-pedunculated,10-20 mm sized colorectal *** identified some statistical deficiencies in this *** addition,we believe that the differences between the treatments failed to achieve significance,and therefore,further analysis is required.

关键词： Comparative analysis Endoscopic mucosal resection precutting Endoscopic mucosal resection Colorectal polyps

Fluconazole and intrathecal injection of amphotericin B for treating cryptococcal meningitis

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Neural Regeneration Research 2006年第8期1卷 753-756页

作者： Shiguang wen jian Yin Shaosen Qin Meiping wen Xiaoyan Zhang Dongke Chen Department of Neurology Beijing Hospital of Ministry of Public Health Beijing 100730China Department of NeurologyBeijing Hospital of Ministry of Public Health Beijing 100730China Department of NeurologyBeijing Hospital of Ministry of Public Health Beijing 100730China Department of NeurologyBeijing Hospital of Ministry of Public Health Beijing 100730China Department of NeurologyBeijing Hospital of Ministry of Public Health Beijing 100730China Department of NeurologyBeijing Hospital of Ministry of Public Health Beijing 100730China

BACKGROUND: At present, fluconazole and intrathecal injection of amphotericin B has been widely used to treat cryptococcal meningitis. However, the application of amphotericin B can shorten course and has good effects on the treatment of cryptococcal meningitis. OBJECTIVE: To observe the effects and poor response of the intrathecal injection of amphotericin B on the treatment of cryptococcal meningitis. DESIGN: Retrospective-case analysis. SETTING: Department of Neurology, Beijing Hospital of Ministry of Public Health. PARTICIPANTS: Eight patients with cryptococcal meningitis were selected from Department of Neurology, Beijing Hospital of Ministry of Public Health from January 1995 to January 2006. Among them, there were 3 males and 5 females aged from 17 to 41 years and the course ranged from 21 days to 3 months. Patients who had symptoms of febrile and headache, positive meninges excitation, positive latex agglutination of cryptococcus of cerebrospinal fluid and positive ink smear were selected in this study. All patients provided informed consent. METHODS: Eight patients were treated with the fluconazole and intrathecal injection of amphotericin B. ① Intracranial hypertension of patients was controlled with flowing cerebrospinal fluid by repeatedly piercing waist; meanwhile, patients were taken the intrathecal injection of amphotericin B combining with flucytosine or fluconazole treatment. The dosage of amphotericin B was 1-5 mg/d at the beginning of administration, and then, the samples were added with 2 mg dexasine and 500 mL 5% glucose solution. The dosage was increased 5.0 mg per day till 50 mg per day, and the total dosage was 3.0-4.0 g. In addition, 2 mg dexasine was mixed with 4.0-5.0 mL cerebrospinal fluid, and then the solution was gradually injected into sheath for once a week. Fluconazole was dripped into vein with the volume of 400 mg per day, and then, 14 days later, fluconazole was orally taken by patients. ② Other therapies, such as decreasing intr

关键词： meningitis cerebrospinal intracranial withdrawal headache administration remarkably conscious twice dosage

Evaluation of radiosensitivity of human tumor cells after irradiation of γ-rays based on G2-chromosome aberrations

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Nuclear Science and Techniques 2006年第5期17卷 268-271页

作者： WANG Zhuan-Zi LI wen-jian YANG jian-She JIN Xiao-Dong WANG Ju-Fang GUO Chuan-Ling Institute of Modern Physics the Chinese Academy of Sciences Lanzhou 730000 China Graduate School of Chinese Academy of Sciences Beijing 100049 China

The aim of the present investigation is to determine initial G2-chromosome aberrations and to validate whether the G2-chromosome aberrations can predict the cellular clonogenic survival in human tumor cell lines. Cell lines of human ovary carcinoma cells (HO8910) and human hepatoma cells (HepG2) were irradiated with a range of doses and assessed both for initial G2-chromosome aberrations and for cell survival after γ -irradiation. The initial G2-chromosome aberrations were measured by counting the number of G2-chromatid breaks after irradiation, detected by the premature chromosome condensation technique, and the G2-assay method. Cell survival was documented by a colony formation assay. A linear-quadratic survival curve was observed in both cell lines. The dose–response results show that the numbers of G2-chromatid breaks increase with the increase in dose in the two cell lines. At higher doses (higher than 4 Gy) of irradiation, the number of G2-chromatid breaks for the G2-assay method cannot be determined because too few cells reach mitosis, and hence their detection is difficult. A good correlation is found between the clonogenic survival and the radiation-induced initial G2-chromatid breaks per cell (r = 0.9616). The present results suggest that the premature chromosome condensation technique may be useful for determining chromatid breaks in G2 cells, and the number of initial G2-chromatid breaks holds promise for predicting the radiosensitivity of tumor cells.

关键词：染色体畸变 γ射线辐射未成熟染色体浓缩放射敏感度人肿瘤细胞群体形成化验

Diamines,CS2 and Monoisocyanide-participated Polymerizations for Large-scale Synthesis of Polythioureas and Thioformamide

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Chinese Journal of Polymer Science 2023年第10期41卷 1563-1576页

作者： Jie Zhang Fan Ye Jin-Lei Huo jian-wen Peng Rong-Rong Hu Ben Zhong Tang State Key Laboratory of Luminescent Materials and Devices Guangdong Provincial Key Laboratory of Luminescence from Molecular AggregatesSouth China University of TechnologyGuangzhou510640China Shenzhen Institute of Aggregate Science and Technology School of Science and EngineeringThe Chinese University of Hong KongShenzhenGuangdong518172China AIE Institute Guangzhou510530China

Multicomponent polymerizations(MCPs)are powerful tools to synthesize functional polymers with great structural diversity,low cost and high efficiency,which usually generate single polymer ***,a robust one-pot diamines,CS_(2)and monoisocyanide-participated catalyst-free polymerization was developed at room temperature to produce polythiourea and thioformamide simultaneously in equal equivalent,which was featured with cheap monomers,simple operation and mild condition,affording various polythioureas with high Mws of up to 4.75×10^(4)g/mol in high yields of up to 98%.Polythioureas with varied chain composition and sequence-controlled structure could be synthesized in 62 g-scale from copolymerization or multicomponent tandem polymerization,enabling facile tuning of thermal property,crystallinity,mechanical property,and *** abundant irregular hydrogen bonds endowed the polythioureas excellent glassy state self-healing property at room temperature or below 0℃.This polymerization provided an efficient and economic approach to access functional polythioureas.

关键词： CS_(2) Multicomponent polymerization Sequence-controlled polythiourea Scale-up synthesis Self-healing

Landau quantization and spin polarization of cold magnetized quark matter

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Chinese Physics C 2022年第6期46卷 164-173页

作者： Zhen-Yan Lu jian-Feng Xu Xin-jian wen Guang-Xiong Peng Marco Ruggieri Hunan Provincial Key Laboratory of Intelligent Sensors and Advanced Sensor Materials School of Physics and ElectronicsHunan University of Science and TechnologyXiangtan 411201China School of Physics and Electrical Engineering Anyang Normal UniversityAnyang 455000China Departrnent of Physics and Institute of Theoretical Physics Shanxi UniversityTaiyuan 030006China School ofNuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China School ofNuclear Science and Technology Lanzhou UniversityLanzhou 730000China

The magnetic field and density behaviors of various thermodynamic quantities of strange quark matter under compact star conditions are investigated in the framework of the thermodynamically self-consistent quasiparticle *** individual species,a larger number density n_(i) leads to a larger magnetic field strength threshold that aligns all particles parallel or antiparallel to the magnetic ***,in contrast to the finite baryon density effect which reduces the spin polarization of magnetized strange quark matter,the magnetic field effect leads to an enhancement of *** also compute the sound velocity as a function of the baryon density and find the sound velocity shows an obvious oscillation with increasing *** for the oscillation,the sound velocity grows with increasing density,similar to the zero-magnetic field case,and approaches the conformal limit V_(s)^(2)=1/3 at high densities from below.

关键词： Landau levels quark matter spin polarization strong magnetic field