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Price Masking Strategy of Cross-Border E-Commerce Platform Financing

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Journal of Systems Science & Complexity 2024年第2期37卷 668-691页

作者： LI Jianbin hang Zhouxin CHEN Zhiyuan xiao Shan School of Management Huazhong University of Science and TechnologyWuhan 430074China School of Economics and Management Wuhan UniversityWuhan 430072China

E-commerce platform financing is a new service pattern of supply chain finance.However,this pattern may bring some new issues when considering the problem of cash flow shortage and financing difficulties of small and medium-sized enterprises.When enterprises use this service,they worry about the leakage of preferential wholesale price when applying the full loan amount and providing the true transaction information.Based on the model consisting of a supplier,a retailer and a cross-border e-commerce platform,the authors design a price masking strategy to prevent the retailer’s preferential wholesale price information from leakage.The authors analyze the profit of the retailer and the platform before and after adopting the price masking strategy.The authors find that the price masking strategy always benefits the retailer.Besides,the optimal profit of the retailer and the platform are both affected by the loan interest rate.Moreover,there exists a range of loan interest rates that can benefit both the retailer and the platform if the price masking strategy is adopted.The research emphasizes that platform can expand the total business volume by allowing retailers to use price masking strategy.In other words,there will be more and more retailers attracted by the strategy,which benefits the long-term growth of cross-border e-commerce platform financing.

关键词： Cross-border e-commerce e-commerce platform financing price masking supply chain finance

Expression and Characterization of a Novelλ-Carrageenase Cgl150A_Wa from Wenyingzhuangia aestuarii

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Journal of Ocean University of China 2024年第1期23卷 209-215页

作者： SUN Yuhao CAO Siqi Zhang Yuying XUE Changhu xiao hang Chang Yaoguang College of Food Science and Engineering Ocean University of ChinaQingdao 266003China Marine Life Research Center Laoshan National LaboratoryQingdao 266237China Department of Food Science University of Massachusetts AmherstMA 01003United States

λ-Carrageenan is a highly sulfated polysaccharide alternating of 1,4-O-α-D-galactopyranose-2,6-sulfate(D2S,6S)and 1,3-O-β-D-galactopyranose-2-sulfate(G2S).λ-Carrageenases are desirable tools forλ-carrageenan degradation.Based on the genome mining,a novelλ-carrageenase Cgl150A_Wa was cloned from the bacterium Wenyingzhuangia aestuarii and expressed in Escherichia coli.Cgl150A_Wa was an endo-acting enzyme and exhibited its maximum activity at 30℃and pH 8.0.By employing a glycomics strategy that combined ultra-performance liquid chromatography-mass spectrometry analysis and glycoinformatics,Cgl150A_Wa was proven to degradeλ-carrageenan octaose and hexaose,and the major hydrolysis product of Cgl150A_Wa wasλ-carrageenan tetrose.In addition to the typicalλ-carrageenan motifs,the active center of Cgl150A_Wa might tolerate desulfatedλ-carrageenan motifs.Cgl150A_Wa is a potential biotechnological tool for preparingλ-carrageenan oligosaccharides and structural investigation.

关键词： carrageenan λ-carrageenase LC-MS oligosaccharide GH150

Fluoro-functionalized plant biomass adsorbent:Preparation and application in extraction of trace perfluorinated compounds from environmental water samples

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Journal of Environmental Sciences 2024年第3期137卷 703-715页

作者： Xi Tan Yan Shi Chun-Feng Ma Quan Chi Yu-hang Yang Wen-Xiang Zhang Hua-Ming xiao Xian Wang Key Laboratory of Analytical Chemistry of the State Ethnic Affairs Commission School of Chemistry and Materials ScienceSouth-Central Minzu UniversityWuhan 430074China School of Pharmaceutical Sciences South-Central Minzu UniversityWuhan 430074China Key Laboratory of Oilseeds Processing of Ministry of Agriculture Hubei Key Laboratory of Lipid Chemistry and NutritionOil Crops Research Institute of the Chinese Academy of Agricultural SciencesWuhan 430062China

Perfuorinated compounds(PFCs)are toxic and widely present in the environment,and therefore effective adsorbents are required to remove PFCs from environmental water.In the present study,a new type of fuorinated biomass materials was synthesized via an ingenious fuorosilanization reaction.These adsorbents were applied for the adsorption of 13typical PFCs,including perfuorocarboxylic acids(PFCAs)and perfuorosulfonic acids(PFSAs).By comparing their adsorption performance,Fluorinated cedar slag(FCS)was discovered to have the best absorption efficiency and enabled highly efficient enrichment of PFCs.The adsorption recovery of FCS with the investigated PFCs is greater than 90%under the optimal adsorption condition.Ascribed to the high affinity of F-F sorbent-sorbate interaction,FCS had good adsorption capacities of PFCs from aqueous solution,with the maximum adsorption capacity of 15.80 mg/g for PFOS and 10.71 mg/g for PFOA,respectively.Moreover,the adsorption time could be achieved in a short time(8 min).Using the FCS absorbent,an innovative FCS-solid phase extraction assisted with high performance liquid chromatography-electrospray-tandem mass spectrometry(FCS-SPE-HPLC-ESI-MS/MS)method was first developed to sensitively detect PFCs in the environmental water samples.The intra-day and inter-day recovery rates of the 13 compounds ranged from 90.7%-104.3%,with the RSD of 2.1%-4.7%(intra-day)and 2.5%-8.5%(inter-day),respectively.This research demonstrates the potential of the newly fuoro-functionalized plant biomass to adsorb PFCs from environmental water,with the advantages of high adsorption efficiencies,high antiinterference,easy operation and low economic cost.

关键词： Fluoro-functionalized biomass Perfuorinated compounds(PFCs) Adsorption efficiency Mass spectrometry(MS) Fluorinated cedar slag(FCS)

Improved nuclear mass formula with an additional term from the Fermi gas model

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Nuclear Science and Techniques 2024年第5期35卷 131-138页

作者： xiao-Yu Xu Li Deng Ai-Xi Chen hang Yang Amir Jalili Han-Kui Wang School of Science Zhejiang Sci-Tech UniversityHangzhou 310018China

Nuclear mass is a fundamental property of nuclear physics and a necessary input in nuclear astrophysics.Owing to the complexity of atomic nuclei and nonperturbative strong interactions,conventional physical models cannot completely describe nuclear binding energies.In this study,the mass formula was improved by considering an additional term from the Fermi gas model.All nuclear masses in the Atomic Mass Evaluation Database were reproduced with a root-mean-square deviation(RMSD)of -1.86 MeV(1.92 MeV).The new mass formula exhibits good performance in the neutron-rich nuclear region.The RMSD decreases to 0.393 MeV when the ratio of the neutron number to the proton number is≥1.6.

关键词： Nuclear mass formula Neutron-rich nuclei Fermi-gas model

On the analytic and geometric aspects of obstruction flatness

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Acta Mathematica Sinica,English Series 2024年

作者： Peter EBENFELT Ming xiao hang XU Department of Mathematics University of California at San Diego School of Mathematics (Zhuhai) Sun Yat-sen University

In this paper, we investigate analytic and geometric properties of obstruction flatness of strongly pseudoconvex CR hypersurfaces of dimension 2n-1. Our first two results concern local aspects. One asserts that any strongly pseudoconvex CR hypersurface M ? Cncan be osculated at a given point p ∈ M by an obstruction flat one up to order 2n + 4 generally and 2n + 5 if and only if p is an obstruction flat point. In the other result, we show that locally there are non-spherical but obstruction flat CR hypersurfaces with transverse symmetry for n = 2. The final main result in this paper concerns the existence of obstruction flat points on compact, strongly pseudoconvex, 3-dimensional CR hypersurfaces. It asserts that the unit sphere in a negative line bundle over a Riemann surface X always has at least one circle of obstruction flat points.

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Catalytic asymmetric dearomative azo-Diels–Alder reaction of 2-vinlyindoles

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Chinese Chemical Letters 2024年第4期35卷 357-362页

作者： Yu-hang Miao Zheng-Xu Zhang Xu-Yi Huang Yuan-Zhao Hua Shi-Kun Jia xiao xiao Min-Can Wang Li-Ping Xu Guang-Jian Mei Green Catalysis Center and College of ChemistryZhengzhou UniversityZhengzhou 450052China School of Chemistry and Chemical Engineering Shandong University of TechnologyZibo 255000China Institute of Pharmaceutical Science and Technology Zhejiang University of TechnologyHangzhou 310014China

Due to the high electrophilic nature of azo-dienophiles, azo-Diels–Alder proceeds rapidly even without the need of a catalyst and is therefore regarded as the “click reaction”. This spontaneity causes strong background reaction and poses a daunting challenge to chemists for developing the catalytic asymmetric version. Reported herein is the first catalytic asymmetric dearomative azo-Diels–Alder reaction between2-vinylindoles and triazoledione. This protocol makes use of the high energy barrier of dearomatization to avert the strong background reaction of azo-Diels–Alder reaction, allowing the implementation of the projected reaction at ambient temperature. Density functional theory calculations have been performed to gain insights into the reaction mechanism and the origins of the enantioselectivity. By using this method,a variety of tetracyclic indole derivatives have been readily prepared in good to excellent yields and with excellent diastereo-and enantio–selectivities(33 examples, up to 97% yield and >99% ee, >20:1 dr).

关键词： Catalytic asymmetric dearomatization Azo-Diels–Alder reaction 2-Vinylindoles Chiral phosphoric acid Tetracyclic indole derivatives

Analysis of the potential biological value of pyruvate dehydrogenase E1 subunitβin human cancer

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World Journal of Gastrointestinal Oncology 2024年第1期16卷 144-181页

作者： Yao Rong Song-Hua Liu Ming-Zheng Tang Zhi-hang Wu Guo-Rong Ma xiao-Feng Li Hui Cai First Clinical Medical College Gansu University of Chinese MedicineLanzhou 730000Gansu ProvinceChina General Surgery Clinical Medical Center Gansu Provincial HospitalLanzhou 730000Gansu ProvinceChina Key Laboratory of Molecular Diagnostics and Precision Medicine for Surgical Oncology in Gansu Province Gansu Provincial HospitalLanzhou 730000Gansu ProvinceChina NHC Key Laboratory of Diagnosis and Therapy of Gastrointestinal Tumor Gansu Provincial HospitalLanzhou 730000Gansu ProvinceChina

BACKGROUND The pyruvate dehydrogenase E1 subunitβ(PDHB)gene which regulates energy metabolism is located in mitochondria.However,few studies have elucidated the role and mechanism of PDHB in different cancers.AIM To comprehensive pan-cancer analysis of PDHB was performed based on bioinformatics approaches to explore its tumor diagnostic and prognostic value and tumor immune relevance in cancer.In vitro experiments were performed to examine the biological regulation of PDHB in liver cancer.METHODS Pan-cancer data related to PDHB were obtained from the Cancer Genome Atlas(TCGA)database.Analysis of the gene expression profiles of PDHB was based on TCGA and Genotype Tissue Expression Dataset databases.Cox regression analysis and Kaplan-Meier methods were used to assess the correlation between PDHB expression and survival prognosis in cancer patients.The correlation between PDHB and receiver operating characteristic diagnostic curve,clinicopathological staging,somatic mutation,tumor mutation burden(TMB),microsatellite instability(MSI),DNA methylation,and drug susceptibility in pan-cancer was also analyzed.Various algorithms were used to analyze the correlation between PDHB and immune cell infiltration and tumor chemotaxis environment,as well as the co-expression analysis of PDHB and immune checkpoint(ICP)genes.The expression and functional phenotype of PDHB in single tumor cells were studied by single-cell sequencing,and the functional enrichment analysis of PDHB-related genes was performed.The study also validated the level of mRNA or protein expression of PDHB in several cancers.Finally,in vitro experiments verified the regulatory effect of PDHB on the proliferation,migration,and invasion of liver cancer.RESULTS PDHB was significantly and differently expressed in most cancers.PDHB was significantly associated with prognosis in patients with a wide range of cancers,including kidney renal clear cell carcinoma,kidney renal papillary cell carcinoma,breast invasive carcinoma,and brain lower grade glioma.In some cancers,P

关键词： Cuprotosis Pyruvate dehydrogenase E1 subunitβ Pan-cancer Prognosis Liver cancer

Fully spin-polarized, valley-polarized and spin-valley-polarized electron beam splitters utilizing zero-line modes in a three-terminal device

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Chinese Physics B 2024年第6期33卷 596-603页

作者：吕小龙杨加恩谢航 College of Science Guangxi University of Science and TechnologyLiuzhou 545006China College of Physics Chongqing UniversityChongqing 401331China Chongqing Key Laboratory for Strongly-Coupled Physics Chongqing UniversityChongqing 401331China

Topological zero-line modes(ZLMs) with spin and valley degrees of freedom give rise to spin, valley and spinvalley transport, which support a platform for exploring quantum transport physics and potential applications in spintronic/valleytronic devices. In this work, we investigate the beam-splitting behaviors of the charge current due to the ZLMs in a three-terminal system. We show that with certain combinations of ZLMs, the incident charge current along the interface between different topological phases can be divided into different polarized currents with unit transmittance in two outgoing terminals. As a result, fully spin-polarized, valley-polarized and spin-valley-polarized electron beam splitters are generated. The mechanism of these splitters is attributed to the cooperative effects of the distribution of the ZLMs and the intervalley and intravalley scatterings that are modulated by the wave-vector mismatch and group velocity mismatch. Interestingly, half-quantized transmittance of these scatterings is found in a fully spin-valley-polarized electron beam splitter.Furthermore, the results indicate that these splitters can be applicable to graphene, silicene, germanene and stanene due to their robustness against the spin–orbit coupling. Our findings offer a new way to understand the transport mechanism and investigate the promising applications of ZLMs.

关键词： topological zero-line modes spin polarization valley polarization quantum transport

Fractional order distance regularized level set method with bias correction

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The Journal of China Universities of Posts and Telecommunications 2024年第1期31卷 64-82页

作者： Cai Xiumei He Ningning Wu Chengmao Liu xiao Liu hang School of Automation Xi'an University of Posts and TelecommunicationsXi'an 710121China School of Electronic Engineering Xi'an University of Posts and TelecommunicationsXi'an 710121China

The existing level set segmentation methods have drawbacks such as poor convergence,poor noise resistance,and long iteration times.In this paper,a fractional order distance regularized level set segmentation method with bias correction is proposed.This method firstly introduces fractional order distance regularized term to punish the deviation between the level set function(LSF)and the signed distance function.Secondly a series of covering template is constructed to calculate fractional derivative and its conjugate of image pixel.Thirdly introducing the offset correction term and fully using the local clustering property of image intensity,the local clustering criterion of image intensity is defined and integrated with the neighborhood center to obtain the global criterion of image segmentation.Finally,the fractional distance regularization,offset correction,and external energy constraints are combined,and the energy optimization segmentation method for noisy image is established by level set.Experimental results show that the proposed method can accurately segment the image,and effectively improve the efficiency and robustness of exiting state of the art level set related algorithms.

关键词： image segmentation fractional order distance regularization level set function fractional derivative bias correction