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Science China Mathematics 2007年第3期50卷 305-312页

作者： Zhi-jian QIU department of economic Mathematics, Southwestern University of Finance and economics, Chengdu 610074, China department of economic Mathematics Southwestern University of Finance and Economics Chengdu China

For a compact subset K in the complex plane, let Rat(K) denote the set of the rational functions with poles off K. Given a finite positive measure with support contained in K, let R2(K,v) denote the closure of Rat(K) in L2(v) and let Sv denote the operator of multiplication by the independent variable z on R2(K, v), that is, Svf = zf for every f∈R2(K, v). SupposeΩis a bounded open subset in the complex plane whose complement has finitely many components and suppose Rat(Ω) is dense in the Hardy space H2(Ω). Letσdenote a harmonic measure forΩ. In this work, we characterize all subnormal operators quasi-similar to Sσ, the operators of the multiplication by z on R2(Ω,σ). We show that for a given v supported onΩ, Sv is quasi-similar to Sσif and only if v/■Ω■σ and log(dv/dσ)∈L1(σ). Our result extends a well-known result of Clary on the unit disk.

关键词： subnormal operator quasi-similarity harmonic measure Hardy space 47B20 30H05 30E10 46E15

Potential of the neonicotinoid imidacloprid and the oxadiazine indoxacarb for controlling five coleopteran pests of stored grain

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Insect Science 2012年第1期19卷 96-101页

作者： Gregory J. Daglish Manoj K. Nayak Agri-Science Queensland Department of Employment Economic Development and Innovation Brisbane Queensland Australia

The potential for using imidacloprid （a neonicotinoid） and indoxacarb （an oxadiazine） as grain protectants was investigated in bioassays against resistant strains of five stored grain beetles. The species investigated were Rhyzopertha dominica （E）（the lesser grain borer）, Sitophilus oryzae （L.）（the rice weevil）, Tribolium castaneum （Herbst）（the rust-red flour beetle）, Oryzaephilus surinamensis （L.）（the saw tooth flour beetle）, and Cryptolestesferrugineus （Stephens）（the fiat grain beetle）. Each of these species has developed resistance to one or more protectants, including organophosphorus insecticides, synthetic pyrethroids and the juvenile hormone analogue methoprene. Mortality and re- production after a 2-week exposure of adults to treated wheat depended on species, dose and insecticide. Imidacloprid had no effect on S. oryzae at any dose, but none of the other species produced any live progeny at 10 mg/kg. Indoxacarb had no effect on T. castaneum at any dose, but none of the other species produced any live progeny at 5 mg/kg. The results show that although both imidacloprid and indoxacarb can control at least four of the five key pests tested at doses comparable to those used for organophosphorus protectants, more potent neonicotinoid or oxadiazine insecticides would be needed than either of these to provide broad spectrum protection of stored grain .

关键词： beetles imidacloprid indoxacarb stored grain

Water quality evaluation of Haihe River with fuzzy similarity measure methods

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Journal of Environmental Sciences 2013年第10期25卷 2041-2046页

作者： Xiaojing Wang Zhihong Zou Hui Zou School of economic and Management Beihang University department of Applied Mathematics College of ScienceChina Agricultural University

Fuzzy similarity measures, which are used to judge the closeness of two fuzzy sets, are presented to evaluate the water quality of the Haihe River. Based on the membership functions and coefficient of variation as the weights, four fuzzy similarity measures （including Lattice similarity measure, Hamming similarity measure, Euclidean similarity measure and the max-min similarity measure） are used to classify the 299 samples into the proper water quality standard ranks. The results are compared with the traditional distance discriminant methods. The calculation of two traditional distance discriminant methods （both Euclidean distance and absolute value distance） is also based on the use of coefficients of variation as the weights. Without the Lattice similarity measure, for this method loses some information, the correct assignment of samples classified into the same water quality ranks is 75.92% with the other three similarity measures and two distance discriminant methods. This result shows the reliability of the five methods. Only considering the three similarity measures, there were only 1.01% of the samples that did not classify to the same ranks, while the corresponding ratio of the two distance discriminant methods was 5.69%. The results of leave-one-out cross validation show that more than 88% of the samples are classified to the proper ranks, which demonstrates that the similarity measures are suitable to evaluate the water quality of the Haihe River.

关键词： similarity measure distance discriminant coefficient of variation membership function

Some Ways to Increase the Security of the Online Interaction Flow between Public Institutions and Citizens or Companies

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Some Ways to Increase the Security of the Online Interaction...

An Improved Graphic Representation for Structured Program Design

2011 International Conference on Applied Social Science(ICASS 2011)

作者： Candidate Daniela Litan Candidate Anca Apostu economic Informatics department Academy of Economic Studies

There can be no discussion related to the performance of an information system, unless there is a discussion about the method its security is provided. Generally speaking, the security of information system is a "delicate" and very controversial issue, but when we cope with the security of e-government type information systems, the matter must be given extra attention. The situation is special, particularly because if there is no proper security provided to e-government type information systems, confidential information may become public and/or used by unauthorized persons, thus endangering the safety of citizens/companies, throwing discredit on the state and on the trust associated with the idea of public or governmental authority. In this paper, we will proceed to the analysis, presentation and comparison of the current most important technologies concerning the possibility of providing the security on an e-government information system（here, we refer to digital certificates and infrastructures with public keys） and, also the methods that can provide security and validation, for example, of the documents part of the interaction flow between a public institution and citizens/companies（here we refer to the digital signature）.

关键词： e-government information systems digital certificate Public Key Infrastructure(PKI) digital signature

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Journal of Computer Science & Technology 1991年第2期6卷 205-208页

作者：周启海 department of economic Information Management Southwestern University of Finance and EconomicsChengdu 610074

In this paper,an improved graphic representation for Structured Program Design——N-S-Z (Nassi-Shneiderman-Zhou Diagram)is *** not only preserves the advantages of the conventional graphic and non-graphic representati... 详细信息

关键词： An Improved Graphic Representation for Structured Program Design

Evaluation of acute and subacute toxicity of whole-plant aqueous extract of Vernonia mespilifolia Less. in Wistar rats

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Journal of Integrative Medicine 2018年第5期16卷 335-341页

作者： Jeremiah Oshiomame Unuofin Gloria Aderonke Otunola Anthony Jide Afolayan Medicinal Plants and economic Development Research Centre Department of BotanyUniversity of Fort Hare

Objective： This study investigated the acute and subacute toxicity of whole-plant aqueous extract of Vernonia mespilifolia Less. （AEVM） in rats for evaluating its safety profile. Methods： AEVM for the acute （2000 and 5000 mg/kg） and subacute （200, 400 and 600 mg/kg） toxicity studies was administered orally to rats according the guidelines 425 and 407 of Organization for economic Cooperation and Development, respectively. Food and water intake as well as body and organ weight of animals were recorded. Signs of toxicity were assessed, and hematological, biochemical and histopathological analyses were performed. Results： In the acute toxicity study, a single dose of the aqueous extract at 2000 or 5000 mg/kg caused no mortality in the animals, suggesting that the median lethal dose is greater than 5000 mg/kg. In the subacute toxicity study, administration of the extract for 28 d, at all doses, caused no significant changes in the body weights or organ weights of rats in the treated groups when compared with the control group. In addition, hematological and biochemical parameters also revealed no toxic effects of the extract on rats. Histological sections of the heart, liver and kidney from test animals showed no signs of degen- eration. Conclusion： These results showed that AEVM at dosage levels up to 600 mg/kg is nontoxic and could also offer protection on some body tissues. AEVM could, therefore, be considered safe.

关键词： Vemonia mespilifolia Less Biochemical parameters Acute toxicity Hematological parameters Subacute toxicity

Mineralogy and Geochemistry of the Pliocene Iron-Rich Laterite in the Vatera Area,Lesvos Island, Greece and Its Genesis

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Chinese Journal Of Geochemistry 2002年第3期21卷 193-205页

作者： A.E. KELEPERTSIS (department of Geology, Section of economic Geology and Geochemistry, University of Athens, Greece) department of Geology Section of Economic Geology and Geochemistry University of Athens Greece

A nickel laterite deposit occurs in the Vatera area of Lesvos Island, Greece, and is transgressively developed on serpentinized basic rock (norite). The overlying sedimentary rocks include marls and marly limestones with sandstone intercalations and belong to the Pliocene sediments. The following lateritic zones are defined from the bottom to top layers: a) bedrock (norite); b) serpentinized zone; c) goethitic zone. The bedrock consists of the following primary minerals: basic plagioclase, orthopyroxenes and clinopyroxenes. The serpentinized zone includes clinochrysotile, lizardite, antigorite clinoenstatite, calcite and dolomite while in the goethic zone there are goethite, quartz, pyrite, chromite, dolomite. Al\-2O\-3, Fe\-2O\-3, CaO, Na\-2O, K\-2O, Ba, Sr, Ni, C and S are enriched in the goethitic zone. Nickel enrichment is related to the formation of nickeliferons minerals substituting for Mg or/and Fe in the goethite and pyrite. Enrichment of Ni in the matrix may be due to the presence of amorphous Ni\|silicates (pimelite). There is a significant change (decrease) in the concentration of Ni from the top to bottom parts of the laterite formation, indicating that there was no tendency to migrate downwards (immature laterite). A second support of the immaturity of the Vatera laterite is the incomplete oxidation of ferrous iron to form ferric iron hydroxides.\; Under tropical/subtropical conditions, which dominated from the end of Miocene to the Pliocene the norite rocks of the Vatera area altered in response to reaction with acid solutions enriched in CO\-2. Due to hydrolysis and oxidation of pyroxenes, Mg\+\{2+\}, H\-4SiO\-4 and Ni\+\{2+\}were removed in the continental acid solutions.

关键词：矿物学地球化学红土成因希腊

Fiscal Residuum and Localization of Foreign Direct Investments among Chinese Provinces

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Frontiers of economics in China-Selected Publications from Chinese Universities 2013年第4期8卷 552-570页

作者： Giuseppe Lucio Gaeta Elina De Simone Salvatore Ercolano department of Humanities and Social Sciences University of Naples L'Orientale 80134 Naples Italy department of economic studies University of Naples Parthenope 80132 Naples Italy

This paper examines the impact of fiscal residuum--the excess of expenditure benefits over tax burdens--on the location choice of foreign direct investments among China＇s provinces. Using data provided by the National Bureau of Statistics of China we propose two fiscal residuum indexes for China＇s provinces over the period 1998-2004. According to Buchanan＇s original definition of fiscal residuum a first index is given by the difference between government expenditure and revenue. A second index measures enterprises＇ net fiscal benefit and is calculated as the difference between public expenditure that affect business activities and taxes paid by enterprises. We found that the first index does not significantly affect the FDI localization choice while the second one positively affects it. When looking at different subsets of provinces we found that for eastern provinces the first index has a positive and significant effect. These results confirm the role of the net fiscal benefit as a determinant of FDI inflows at the provincial level.

关键词： China foreign direct investments fiscal residuum

Irreversible electroporation for metastatic pancreatic carcinoma with liver metastasis:What does the evidence say

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World Journal of Clinical Cases 2025年第3期13卷 30-34页

作者： Ranit Seal Akash Bararia Bitan Kumar Chattopadhyay Nilabja Sikdar department of General Surgery IPGME&R and SSKM HospitalKolkata 700020West BengalIndia Human Genetics Unit Indian Statistical InstituteKolkata 700108West BengalIndia Estaurine and Coastal studies Foundation Howrah 711101India

Irreversible electroporation is a promising non-thermal ablation method that has been shown to increase overall survival in locally advanced pancreatic cancer in some ***,higher quality studies with proper controls and randomization are required to establish its superiority when added with neoadjuvant chemotherapy over the current management of choice,which is chemotherapy *** studies are required before establishment of any survival benefit in metastatic pancreatic carcinoma,and such evidence is lacking at present.

关键词： Irreversible electroporation Locally advanced pancreatic carcinoma Metastatic pancreatic carcinoma Advanced pancreatic carcinoma Chemotherapy