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Farmers using insurance and cooperatives to manage agricultural risks: A case study of the swine industry in China

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Journal of Integrative Agriculture 2019年第12期18卷 2910-2918页

作者： zhang yan-yuan JU Guang-wei ZHAN Jin-tao College of Economics and Management Nanjing Forestry UniversityNanjing 210037P.R.China Chinese Academy of Agricultural Sciences Beijing 100081P.R.China College of Economics and Management Nanjing Agricultural UniversityNanjing 210095P.R.China

Purchasing agricultural insurance and joining agricultural cooperatives are two prevalent instruments used by farmers in China for dealing with agricultural risks. Data from 443 swine farmers in Jiangsu and Henan provinces of China were collected. Factors affecting the farmers’ decision to purchase agricultural insurance and join agricultural cooperatives were assessed. The possibility of simultaneous use of both instruments and the potential correlation between these two decisions was considered as well. Results showed that the farmers’ decision to use agricultural insurance and cooperatives was positively correlated, indicating that farmers who purchased agricultural insurance which mainly used to mitigate production risks were more likely to join agricultural cooperatives which more used to share market risks, and vice versa. Farmers’ knowledge of swine insurance and trust in the local government positively impacted the purchase of agricultural insurance, while education, years involved in swine production and scale of swine production positively impacted farmers joining agricultural cooperatives.

关键词： agricultural insurance agricultural cooperatives simultaneous decisions Bivariate Probit China

Quantum Effect in a Diode Included Nonlinear Inductance-Capacitance Mesoscopic Circuit

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Communications in Theoretical Physics 2009年第9期52卷 534-538页

作者： yan Zhan-yuan zhang Xiao-Hong MA Jin-Ying School of Mathematics and Applied Physics North China Electric Power University Baoding 071003 China

The mesoscopic nonlinear inductance-capacitance circuit is a typical anharmonie oscillator, due to diodes included in the circuit. In this paper, using the advanced quantum theory of mesoseopie circuits, which based on the fundamental fact that the electric charge takes discrete value, the diode included mesoscopic circuit is firstly studied. Schrodinger equation of the system is a four-order difference equation in p rep asentation. Using the extended perturbative method, the detail energy spectrum and wave functions axe obtained and verified, as an application of the results, the current quantum fluctuation in the ground state is calculated. Diode is a basis component in a circuit, its quantization would popularize the quantum theory of mesoscopie circuits. The methods to solve the high order difference equation are helpful to the application of mesoscopic quantum theory.

关键词： mesoscopic circuit quantum effects

Quantum Effect in Mesoscopic Open Electron Resonator

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Communications in Theoretical Physics 2008年第8期50卷 521-524页

作者： yan Zhan-yuan zhang Xiao-Hong HAN Ying-Hui School of Mathematics and Applied Physics North China Electric Power University Baoding 071003 China

The open electron resonator is a mesoscopic device that has attracted considerable attention due to its remarkable behavior： conductance oscillations. In this paper, using an improved quantum theory to mesoscopic circuits developed recently by Li and Chen, the mesoscopic electron resonator is quantized based on the fundamental fact that the electric charge takes discrete value. With presentation transformation and unitary transformation, the SchrSdinger equation becomes an standard Mathieu equation. Then, the detailed energy spectrum and wave functions in the system axe obtained, which will be helpful to the observation of other characters of electron resonator. The average of currents and square of the current are calculated, the results show the existence of the current fluctuation, which causes the noise in the circuits, the influence of inductance to the noise is discussed. With the results achieved, the stability characters of mesoscopic electron resonator are studied firstly, these works would be benefit to the design and control of integrate circuit.

关键词： mesoscopic circuit Mathieu equation quantum effect

Synthesis and Characterization of Dual Acidic Ionic Liquids

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Chinese Chemical Letters 2005年第12期16卷 1563-1565页

作者： Xiao Hua WANG Guo Hong TAO Zi yan zhang yuan KOU State Key Laboratory for Structural Chemistry of Unstable and Stable Species College of Chemistry and Molecular Engineering Peking University Beijing 100871

Novel ionic liquids with dual acidity, of which the cation contains Brφnsted acidity and anions contain Lewis acidity were synthesized. These ionic liquids obtained were identified by NMR, FF-IR, SDT and FAB-MS. Thei... 详细信息

关键词： Ionic liquids functional dual acidity synthesis characterization

New furo[3,2-h]isochroman from the mangrove endophytic fungus Aspergillus sp. 085242

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Chinese Journal of Natural Medicines 2020年第11期18卷 855-859页

作者： GUO Hui-Xian HUANG Cui-Ying yan zhang-yuan CHEN Tao HONG Kui LONG Yu-Hua School of Chemistry Guangzhou Key Laboratory of Analytical Chemistry for BiomedicineSouh China Normal UniversiyGuangzhou 510006China Key Laboratory of Combinatorial Biosynthesis and Drug Discovery(Wuhan University) Ministry of Educationand Wuhan University School of Pharmaceutical SciencesWuhan430071China

Four new compounds, asperisocoumarin G(1), asperisocoumarin H(2),(±)-asperisocoumarin I [(±)-3], along with the known pergillin(4) and penicisochroman L(5) were isolated from a mangrove endophytic fungus Aspergillus sp. 085242 by further chemical investigation. The structures of the new compounds, including their absolute configurations, were established by analysis of HR-ESI-MS and NMR spectroscopic data, and ECD calculation. Asperisocoumarins G-I(1-3) were new isocoumarins belonging to the class of furo[3, 2-h]isocoumarins which are rarely found in natural sources. All of the isolated compounds were evaluated for theirα-glucosidase inhibitory effects, and compounds 1 and 4 showed moderate α-glucosidase inhibitory activity, respectively. In an antimicrobial test, the racemate of 3 showed antibacterial activity against Salmonella.

关键词： Aspergillus Furo[3 2-h]isocoumarins α-Glucosidase inhibitory activity Antimicrobial activity

Management of head and neck hemangiomas in China

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Chinese Medical Journal 2008年第11期121卷 1037-1042页

作者： ZHENG Jia-wei ZHOU Guo-yu WANG yan-an zhang Zhi-yuan Department of Oral and Maxillofacial Surgery College of Stomatology Ninth People's Hospital School of MedicineShanghai Jiao Tong University Shanghai 200011 China

Hemangioma is a common benign vascular tumor,with an incidence of 2%-3% in the neonate and 10%in baby after 1 year.^1 The incidence of hemangiomas is approximately 22%-30% of preterm infants with birthweight less than 1000 g. The development of hemangioma is therefore supposed to be related to various intra- and extra-uterine factors.

关键词： hemangioma head and neck treatment

Primary Studies on Burnup Estimation of Irradiated Uranium by Dtermining 236U/238U in Contaminated Environmental Samples JIANG Xiao-yan,zhang Ji-long,ZOU Wei,Chang Zhi-yuan

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Primary Studies on Burnup Estimation of Irradiated Uranium b...

Annexin A2 promotes choroidal neovascularization by increasing vascular endothelial growth factor expression in a rat model of argon laser coagulation-induced choroidal neovascularization

作者： JIANG Xiao-yan zhang Ji-long ZOU Wei Chang Zhi-yuan

U/U of the environmental sample can indicate the existence of uranium irradiation,and even can be uesd to estimate the burnup of nuclear spent fuel.A study on the burnup estimation of irradiated uranium which was mixed with natural uranium was carried out by measuring the U/U and U/U in the samples by using MC-ICP-MS. According to the equation(1) and(2),a programme for calculating the burnup of the irradiated

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Chinese Medical Journal 2010年第6期123卷 713-721页

作者： ZHAO Shi-hong PAN Dong-yan zhang yuan WU Jin-hui LIU Xin XU Yu Department of Ophthalmology Changhai HospitalSecond Military Medical UniversityShanghai 200433China

Background Choroidal neovascularization （CNV） is a common cause of visual loss in the elderly patients with age-related macular degeneration and represents the growth of subretinal new vessels in the macular region. This study aimed to investigate the relationship between annexin A2 （ANXA2） and vascular endothelial growth factor （VEGF） in *** In a rat model of argon laser coagulation-induced CNV, the mRNA expressions of the annexins and VEGF protein expression in the retina were detected using fluorescent real-time polymerase chain reaction （PCR） and immunohistochemistry, respectively. The interactions between ANXA2 and VEGF in both a retinal pigment epithelial cell line RPE-J and the rat model of CNV were examined by means of RNA interference, real-time PCR, Western blotting, enzyme-linked immunosorbent assay （ELISA） and histopathological examinations. Results Fundus fluorescein angiography （FFA） showed that argon laser coagulation of the retina induced stable CNV models in the rats. Two to three weeks after the coagulation, ANXA2. and VEGF expressions in the coagulated area in the retina and choroid increased to the peak level, while the other annexin members （ANXA4, ANXA5, ANXA7 and ANXA11） showed no obvious changes. In RPE-J cells and the CNV model, RNA interference of ANXA2 gene significantly lowered the VEGF protein and mRNA expressions, and application of an adenoviral vector containing ANXA2 gene markedly increased VEGF expressions in the rat model of CNV, but produced no significant effects on the expressions of the kinase insert domain-containing receptor （KDR） or the fms-like tyrosine kinase （Fit-l）. The expression of KDR inhibited the increment in ANXA2 expression, but VEGF and Rt-1 did not directly affect ANXA2 expression. Conclusion Besides the role as a plasminogen and the receptor of tissue plasminogen activator, ANXA2, which is under regulation of KDR via a negative feedback mechanism, also participates in neovascularization by regulating VE

关键词： annexin A2 vascular endothelial growth factor choroid neovascularization

Data Storage Framework on Flash Memory using Object-based Storage Model

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Data Storage Framework on Flash Memory using Object-based St...