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Hepatitis B transmission by cell and tissue allografts:How safe is safe enough?

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World Journal of Gastroenterology 2014年第23期20卷 7434-7441页

作者： Pilar Solves Vicente Mirabet Manuel Alvarez Blood bank Hospital Universitari I Politècnic La FeBulevar Sur46026 ValenciaSpain

More than 2 million human tissue transplants(bone,tendon,cartilage,skin,cornea,amniotic membrane,stem cells,heart valve,blood vessel,etc.),are performed worldwide every *** and tissues are shared between countries which have different regulations and laboratory equipment and represent a risk of hepatitis B virus(HBV)transmission that has become a global safety *** the risk of transfusiontransmitted HBV infection from blood donations has been estimated,the rate of HBV transmission from donors to recipients of allografts is unknown and varies between different *** are various important ways of reducing the transmission risk,but donor screening and donor testing are still the main factors for preventing HBV *** detection is included in the routine screening tests for cell and tissue *** standard test for preventing transplant-transmitted hepatitis B is the hepatitis B surface *** implementation of methods involving nucleic acid amplification and the new generation of reactives to detect viral antibodies or antigens with an immunoassay,has increased the sensitivity and the specificity of the screening *** objective of our research was to review the literature and critically analyse the different steps for avoiding HBV transmission in cell and tissue donors,focusing on the screening tests performed.

关键词： Hepatitis B virus Tissue bank Tissue transplantation

Financing Constraints and the Mode of Outward Foreign Direct Investment:Cross-Border Mergers and Acquisitions or Greenfield Investment

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China Finance and Economic Review 2020年第4期9卷 46-66页

作者： Guanhong Jiang Jing Zeng Department of International Economics and Business Xiamen University Shanghai bank Master candidate

In this paper,two investment modes,greenfield investment and cross-border mergers and acquisitions,are introduced on the basis of Manova(2008),and it is found that enterprises with less financing constraints tend to choose cross-border mergers and ***,this paper takes Chinese industrial enterprises that conducted cross-border mergers and acquisitions and greenfield investment in 2003−2010 as examples to test the above *** result shows that enterprises with lower financing constraints are more likely to choose cross-border mergers and acquisitions,while those with stronger constraints choose greenfield *** specifi cally,a 1%reduction in financing constraints raises the probability of choosing cross-border mergers and acquisitions by 2.51%.The authors also find that the influence of financing constraints varies under different investment *** business service and production-related investment,enterprises with lower financing constraints tend to choose cross-border mergers and acquisitions;while for R&D investment,financing constraints have no impact on the choice of investment mode.

关键词： financing constraints outward foreign direct investment cross-border mergers and acquisitions greenfield investment

A Credit Card Fraud Detection Model Based on Multi-Feature Fusion and Generative Adversarial Network

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Computers, Materials & Continua 2023年第9期76卷 2707-2726页

作者： Yalong Xie Aiping Li Biyin Hu Liqun Gao Hongkui Tu College of Computer National University of Defense TechnologyChangsha410003China Credit Card Department Bank of ChangshaChangsha410016China

Credit Card Fraud Detection(CCFD)is an essential technology for banking institutions to control fraud risks and safeguard their *** imbalance and insufficient representation of feature data relating to credit card transactions are two prevalent issues in the current study field of CCFD,which significantly impact classification models’*** address these issues,this research proposes a novel CCFD model based on Multifeature Fusion and Generative Adversarial Networks(MFGAN).The MFGAN model consists of two modules:a multi-feature fusion module for integrating static and dynamic behavior data of cardholders into a unified highdimensional feature space,and a balance module based on the generative adversarial network to decrease the class imbalance *** effectiveness of theMFGAN model is validated on two actual credit card *** impacts of different class balance ratios on the performance of the four resamplingmodels are analyzed,and the contribution of the two different modules to the performance of the MFGAN model is investigated via ablation *** results demonstrate that the proposed model does better than state-of-the-art models in terms of recall,F1,and Area Under the Curve(AUC)metrics,which means that the MFGAN model can help banks find more fraudulent transactions and reduce fraud losses.

关键词： Credit card fraud detection imbalanced classification feature fusion generative adversarial networks anti-fraud systems

Price Discovery Function of Index Futures in China: Evidence from Daily Closing Prices

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Economic and Political Studies 2013年第2期1卷 40-54页

作者： SHIQING XIE JIAJUN HUANG Department of Finance School of Economics Peking University bank of China Macao Branch

Price discovery is one of the main functions of stock index *** the daily closing prices of the CSI 300 index and its index futures from April 2010 to April 2012,this paper applies a vector error correction model(VECM)and an impulse response function to conduct an empirical analysis on the price discovery function of index futures in *** paper has the following four findings:(1)a solid cointegration relationship between the CSI 300 index and its index futures exists in the long run;(2)when prices deviate from the longterm equilibrium,the stock index reverses weakly,while the reversal of index futures is much stronger;(3)the daily lead-lag relationship between the prices of the CSI 300 index and its index futures contracts is not significant in the short run;()shocks from the spot market have a lasting impact upon the futures market,but not vice versa,due to the limited short-term adjustment ability of the spot market.

关键词： price discovery CSI 300 index futures vector error correction model impulse response functions

Constructing Damage Indices Based on Publicly Available Spatial Data:Exemplified by Earthquakes and Volcanic Eruptions in Indonesia

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International Journal of Disaster Risk Science 2021年第3期12卷 410-427页

作者： Emmanuel Skoufias Eric Strobl Thomas Tveit Poverty and Equity Global Practice World BankWashingtonDC 20433USA Department of Economics University of Bern3012 BernSwitzerland

This article demonstrates the construction of earthquake and volcano damage indices using publicly available remote sensing sources and data on the physical characteristics of *** earthquakes we use peak ground motion maps in conjunction with building type fragility curves to construct a local damage *** volcanoes we employ volcanic ash data as a proxy for local *** indices are then spatially aggregated by taking local economic exposure into account by assessing nightlight intensity derived from satellite *** demonstrate the use of these indices with a case study of Indonesia,a country frequently exposed to earthquakes and volcanic *** results show that the indices capture the areas with the highest damage,and we provide overviews of the modeled aggregated damage for all provinces and districts in Indonesia for the time period 2004 to *** indices were constructed using a combination of software programs—ArcGIS/Python,Matlab,and *** also outline what potential freeware alternatives ***,for each index we highlight the assumptions and limitations that a potential practitioner needs to be aware of.

关键词： Damage indices Indonesia Natural hazard modeling Remote sensing data

The role of phosphorus in the metabolism of arsenate by a freshwater green alga, Chlorella vulgaris

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Journal of Environmental Sciences 2016年第11期28卷 169-178页

作者： Josh Baker Dirk Wallschlager Trent University Environmental and Life Sciences Graduate Program 1600 West Bank Dr Peterborough ON K9L 0G2 Canada School of the Environment Department of Chemistry and Water Quality Centre Trent University 1600 West Bank Dr Peterborough ONK9L 0G2 Canada

A freshwater microalga, Chlorella vulgaris, was grown in the presence of varying phosphate concentrations（〈 10–500 μg/L P） and environmentally realistic concentrations of arsenate（As（Ⅴ））（5–50 μg/L As）. Arsenic speciation in the culture medium and total cellular arsenic were measured using AEC-ICP-MS and ICP-DRC-MS, respectively, to determine arsenic biotransformation and uptake in the various phosphorus scenarios. At high phosphate concentration in the culture medium, 〉 100 μg/L P, the uptake and biotransformation of As（Ⅴ） was minimal and dimethylarsonate（DMAs（Ⅴ）） was the dominant metabolite excreted by C. vulgaris, albeit at relatively low concentrations. At common environmental P concentrations, 0–50 μg/L P, the uptake and biotransformation of As（Ⅴ） increased. At these higher As-uptake levels, arsenite（As（Ⅲ）） was the predominant metabolite excreted from the cell. The concentrations of As（Ⅲ） in these low P conditions were much higher than the concentrations of methylated arsenicals observed at the various P concentrations studied. The switchover threshold between the（small） methylation and（large） reduction of As（Ⅴ） occurred around a cellular As concentration of 1 fg/cell. The observed nearly quantitative conversion of As（Ⅴ） to As（Ⅲ） under low phosphate conditions indicates the importance of As（Ⅴ） bio-reduction at common freshwater P concentrations. These findings on the influence of phosphorus on arsenic uptake, accumulation and excretion are discussed in relation to previously published research. The impact that the two scenarios of As（Ⅴ） metabolism, As（Ⅲ） excretion at high As（Ⅴ）-uptake and methylarsenical excretion at low As（Ⅴ）-uptake, have on freshwater arsenic speciation is discussed.

关键词： Arsenic Speciation Phosphorus Freshwater algae Toxicity Biotransformation

Assessment of achievements of the Lima Climate Change Conference and perspectives on the future

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Advances in Climate Change Research 2014年第4期5卷 219-223页

作者： L Xue-Du National Climate Center China Meteorological Administration Asian Development bank

The Lima call for climate action adopted at the Lima Climate Conference on Climate Change specifies that the principles of the United Nations Framework Convention on Climate Change,including the principle of common but differentiated responsibilities,shall apply to the new climate agreement to be adopted at the Paris Conference on Climate Change in *** on other heavily debated items,including the intended nationally determined contributions,were also made at the Lima *** significant achievements in Lima and the positive momentum have laid a solid foundation for the adoption of a new climate agreement in the Paris Climate *** measures are proposed for China to meet great challenges in addressing climate change beyond 2020,including early formulation and issuance of a climate change law,establishment of a greenhouse gas emission trading scheme,promotion of advanced climate technology investments,and further international engagement for climate change.

关键词： Lima Climate Change Conference Ad Hoc Working Group on the Durban Platform for Enhanced Action Greenhouse gas mitigation Climate changenegotiation Carbon market Common but differentiated responsibilities

Rational and Periodic Solutions for a (2+1)-Dimensional Breaking Soliton Equation Associated with ZS-AKNS Hierarchy

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Communications in Theoretical Physics 2010年第3期53卷 430-434页

作者：郝宏海张大军张建兵姚玉芹 Department of Plan and Finance Hebei BranchChina Construction Bank Department of Mathematics Shanghai University Department of Mathematics Tsinghua University

The double Wronskian solutions whose entries satisfy matrix equation for a （2＋1）-dimensional breaking soliton equation （（2＋ 1）DBSE） associated with the ZS-AKNS hierarchy are derived through the Wronskian technique. Rational and periodic solutions for （2＋1）DBSE are obtained by taking special eases in general double Wronskian solutions.

关键词： (2+1)DBSE double Wronskian rational solution periodic solution

Financial Risks and Monetary Policy

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China Economic Transition 2019年第1期2卷 1-16页

作者： LIAN Ping of bank of Communications

Risks brought by the rapid shrinkage of social financing scale In recent years,Chinese central government has proposed“deleveraging.”Undoubtedly,increases in the scale of social financing should be contained;however... 详细信息

关键词： Financial shrink brought