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Does Green Food Certification promote agri-food export quality?Evidence from China

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Journal of Integrative Agriculture 2024年第3期23卷 1061-1074页

作者： ping Wei Hongman liu Chaokai Xu Shibin Wen College of Economics and Management China Agricultural UniversityBeijing 100083China School of Public Affairs Zhejiang UniversityHangzhou 310058China

The construction of a food certification system plays a vital role in upgrading export quality, which previous studies have largely overlooked. We match China's industry-level data of Green Food Certification with its HS6-digit export data of agri-food products to quantify the impact of Green Food Certification on export quality. We identify the significant and positive effect of Green Food Certification on export quality. The 2SLS estimation based on instrumental variables and a range of robustness checks confirm the validity and robustness of the benchmark conclusions. Further analysis discloses that Green Food Certification improves export quality by raising agricultural production efficiency and brand premiums. Heterogeneity analysis shows that the effect of Green Food Certification varies across regions, notably improving the quality of agri-food products exported to developed regions and regions with high levels of import supervision. Furthermore, among various product types, Green Food Certification significantly improves the export quality of primary products and products vulnerable to non-tariff measures. The above findings could guide the future development of agri-food quality certification systems, potentially leading to a transformation and promotion of the agri-food trade.

关键词： Green Food Certification agri-food products green transformation export quality food labeling

Jurassic integrative stratigraphy,biotas,and paleogeographical evolution of the Qinghai-Tibetan Plateau and its surrounding areas

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Science China Earth Sciences 2024年第4期67卷 1195-1228页

作者： Jianguo LI xin RAO Lin MU Xiaohui CUI xin LI Hui LUO Peixue liu Center for Excellence in Life and Paleoenvironment Nanjing Institute of Geology and PalaeontologyChinese Academy of SciencesNanjing 210008China Nanjing College University of Chinese Academy of SciencesNanjing 211135China

The Qinghai-Tibetan Plateau experienced a unique geological evolution during the Jurassic,driven by the termination of the Palaeotethys and the reduction of the *** Indian Plate separated from the northern margin of Gondwana and drifted northward from the Southern *** that the timing of strata serves as the basis for reconstructing geological history,the present work aimed to develop a new multiple stratigraphic and chronologic framework for the Jurassic strata of the Qinghai-Tibetan Plateau region via a synthesis of the material on lithostratigraphy,palaeontology,iso-radiometric dating,magnetostratigraphy,and other techniques with an emphasis on recent progress and *** new framework included the Jurassic System from the four major subdivisions of the plateau:the Baryan Har,Qiangtang,Lhasa-Gandise,and Southern Xizang(Himalaya).Ultimately,a more complete,refined biostratigraphic sequence was proposed,comprising the most common fossils in the plateau and those that are stratigraphically significant for the Jurassic stratigraphy,including ammonites,bivalves,brachiopods,foraminifera,radiolarians,and dinoflagellate cysts for the marine strata,and pollen and spores,and charophytes for the terrestrial *** biostratigraphic framework was correlated with the Jurassic international standard zonation of the Geological Time Scale 2020 via standard or representative species or genera of *** on this framework,we constructed a lateral correlation of the Jurassic strata between different basins of the *** palaeontologic correlation in the present work shows that the Lhasa-Gandise Block had a closer relationship with the Qiangtang Block than with the Southern Xizang Himalaya during the Jurassic ***,the Lhasa-Gandise Block and Qiangtang Block shared similar marine fauna features of the north marginal East *** contrasts the opinion suggesting that the Yarlung Zangbo Tethys was a small back-arc basin.A c

关键词： Biostratigraphy Chronostratigraphy Correlation Yarlung Zangbo suture Bangong Co-Nujiang suture Tethys

Reproductive biology of Hemitripterus villosus in the Bohai Strait,China

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Journal of Oceanology and Limnology 2024年第3期42卷 881-892页

作者： ping SUN Song QIN Zhengyi liu Longchuan ZHUANG Key Laboratory of Coastal Biology and Biological Resource Utilization Yantai Institute of Coastal Zone ResearchChinese Academy of SciencesYantai 264003China University of Chinese Academy of Sciences Beijing 100049China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China

To understand the reproductive biology of Hemitripterus villosus in the Bohai Strait,and fill the key knowledge gap in verifying reproductive seasonality and documenting gonadotropin dependent reproductive cycle of this species,a year-round detail study was conducted for the first *** total,263 individuals were randomly sampled off the coasts of the Bohai *** show that and the overall female-to-male ratio(1.35:1)did not differ significantly from the 1:1 sex *** length and weight relationship for females and males were regressed,depicting an isometric growth for both *** reproductive phases of the complete gonadotropin dependent reproductive cycle in both sexes were *** monthly variations in the gonadosomatic and hepatosomatic indexes for both sexes further indicated that this species spawns a single batch of eggs per year and the peak spawning period is from October to *** average diameter of eggs ranged from 2.10 to 3.57 *** length at first sexual maturity was 224.87 mm for females and 241.26 mm for *** positive relationships between absolute fecundity and fish size,and also gonadal weight were *** from the Bohai Strait exhibited smaller body size,smaller egg diameter,lower gonadosomatic index,lower absolute fecundity,and higher population extinction risk than the other populations’studied *** findings contribute to understanding the status of this isolated westernmost population,and we emphasize that more efficient protection measures for the species and control measures are urgently required to improve the coastal environment in the Bohai Strait.

关键词： Hemitripterus villosus Bohai Strait fecundity length at first maturity reproductive seasonality

Accurate simulations of pure-viscoacoustic wave propagation in tilted transversely isotropic media

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Petroleum Science 2024年第2期21卷 866-884页

作者： Qiang Mao Jian-ping Huang xin-Ru Mu Ji-Dong Yang Yu-Jian Zhang Geosciences Department China University of Petroleum(East China)Qingdao266580ShandongChina Pilot National Laboratory for Marine Science and Technology(Qingdao) Qingdao266207ShandongChina

Forward modeling of seismic wave propagation is crucial for the realization of reverse time migration(RTM) and full waveform inversion(FWI) in attenuating transversely isotropic media. To describe the attenuation and anisotropy properties of subsurface media, the pure-viscoacoustic anisotropic wave equations are established for wavefield simulations, because they can provide clear and stable wavefields. However, due to the use of several approximations in deriving the wave equation and the introduction of a fractional Laplacian approximation in solving the derived equation, the wavefields simulated by the previous pure-viscoacoustic tilted transversely isotropic(TTI) wave equations has low accuracy. To accurately simulate wavefields in media with velocity anisotropy and attenuation anisotropy, we first derive a new pure-viscoacoustic TTI wave equation from the exact complex-valued dispersion formula in viscoelastic vertical transversely isotropic(VTI) media. Then, we present the hybrid finite-difference and low-rank decomposition(HFDLRD) method to accurately solve our proposed pure-viscoacoustic TTI wave equation. Theoretical analysis and numerical examples suggest that our pure-viscoacoustic TTI wave equation has higher accuracy than previous pure-viscoacoustic TTI wave equations in describing q P-wave kinematic and attenuation characteristics. Additionally, the numerical experiment in a simple two-layer model shows that the HFDLRD technique outperforms the hybrid finite-difference and pseudo-spectral(HFDPS) method in terms of accuracy of wavefield modeling.

关键词： Pure-viscoacoustic TTI wave equation Attenuation anisotropy Seismic modeling Low-rank decomposition method

Encouraging Solution to the Problem of Synthesizing Protein α-Thioester

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Chinese Journal of Chemistry 2024年第10期42卷 1114-1120页

作者： xinliang liu Zijun Gao Jie Zhao Farong Ye ping Huang ping Wang Center for Chemical Glycobiology Shanghai Key Laboratory for Molecular Engineering of Chiral DrugsFrontiers Science Center for Transformative MoleculesSchool of Chemistry and Chemical EngineeringZhangjiang Institute for Advanced StudyShanghai JiaoTongUniversityShanghai 200240China Shenzhen Research Institute of Shanghai Jiao Tong University ShenzhenGuangdong 518057China

Expressed protein ligation(EPL)provides a powerful tool to access large-size proteins with precise *** methods for constructing the critical protein thioester for EPL have predominantly relied on the recombinant intein fusion expressed in Escherichia coli(***).Despite its powerful applications,the expression of thioester derived from eukaryotic protein in *** inherently suffers from its limited solubility,the inactivity of intein,premature hydrolysis and low *** overcome these obstacles,we present herein the facile one-flask synthesis of inaccessible proteinα-thioester via a SUMO-protein-intein(SPI)sandwich *** utility of SUMO enhances the protein fusion yield and solubility,prevents premature hydrolysis and simplifies the purification *** inaccessible protein thioester with internal Cys residues can be readily produced and is compatible with the EPL-desulfurization protocol used to prepare complex proteins,which is otherwise difficult to obtain using traditional *** utility has been highlighted through the synthesis of human granulocyte colony-stimulating factor(G-CSF).

关键词： Desulfurization Glycoproteins Glycopeptides Protein expression Peptide thioester

Stable hydrogen-bonded organic frameworks and their photo-and electro-responses

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Nano Research 2024年第8期17卷 7675-7699页

作者： Ying Hou xin-Song Huang Sheng-Hao Gong Chen liu Yangyang liu Tian-Fu liu State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China University of Chinese Academy of Sciences Beijing 100049China Department of Chemistry and Biochemistry California State UniversityLos AngelesCalifornia 90032USA College of Chemistry and Materials Science Fujian Normal UniversityFuzhou 350007China

Hydrogen-bonded organic frameworks(HOFs)are a recent class of porous materials that have garnered considerable research interest owing to their distinctive *** can be constructed through judicious selection of H-bonding motifs,which are further enforced by other weak intermolecular interactions such asπ–πstacking,van der Waals forces,and framework *** advantage of these interactions,we can expand the functional field of HOFs by introducing active ***,researchers have made substantial advancements in using HOFs for chemical sensing,catalysis,proton conduction,biological applications,and *** low bonding energy of H-bonds allows for precise control over the concentration of ligands in solvents,forming diverse HOF *** varied structures offer significant advantages for producing HOFs with photo-responsive and electro-responsive ***,the presence of H-bonds in HOFs results in their inherent lower stability compared to metal-organic frameworks(MOFs)and covalent-organic frameworks(COFs)formed via coordination and covalent bonds,*** a result,the pursuit of stable and innovative HOF materials with novel functional sites remains an ongoing *** review provides an overview of recent research progress in the development of new strategies for stable HOF synthesis and applications of HOFs with stimuli-responsive *** first classified all synthetic methods reported to date and discussed the stable HOFs synthesized,as well as their unique properties and *** addition,we summarized the applications of HOFs utilizing their synergistic responses to external stimuli,including photo,electrical,pressure,and chemical *** systematically reviewed stable HOF synthesis and applications,which may lead to a deeper understanding of the structure–activity relationship for these materials and guide future HOF design.

关键词： stable hydrogen-bonded organic frameworks(HOFs) photo-response electro-response photoelectric synergistic response

Chronic administration of triclosan leads to liver fibrosis through hepcidin-ferroportin axis-mediated iron overload

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Journal of Environmental Sciences 2024年第3期137卷 144-154页

作者： Jing liu Lecong Zhang Fang Xu ping Zhang Yang Song College of Eco-Environmental Engineering Guizhou Minzu UniversityGuiyang 550025China The Institute of Karst Wetland Ecology Guizhou Minzu UniversityGuiyang 550025China State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China

Triclosan(TCS)has been manufactured as an antibacterial compound for half a ***,it is widely used in various personal care products;however,its potential adverse effects raise a lot of ***,we create a long-term oral administration mouse model and identify the corresponding hepatotoxicity of *** discover that daily intragastric administration of 10 mg/kg TCS to mice for 12 weeks results in severe hepatic *** study displays that hepatic iron increased 18%,23%and 29%upon oral TCS treatment for4,8 and 12 weeks,*** by hepatic iron variation,splenic and duodenal iron are increased,which indicates systemic iron *** only excessive iron accumulated in the liver,abnormal hepatic malondialdehyde,prostaglandin synthase 2 and glutathione peroxidase 4 are pointed to *** study uncovers that hepcidin expression increases 7%,10%,4%in serum and 2.4-,4.8-,and 2.3-fold on transcriptional levels upon TCS exposure for 4,8 and 12 weeks,*** together,the mice in the TCS-treated group show disordered systemic iron homeostasis via the upregulated hepatic hepcidin-ferroportin ***,both hepatic iron overload(systemic level)and hepatocyte ferroptosis(cellular level)are accused of TCS-induced liver ***■,an iron scavenger,significantly ameliorates TCS-induced liver *** summary,this study confirms the impact of TCS on liver fibrosis;a critical signal pathway is also *** significance of the current study is to prompt us to reevaluate the“pros and cons”of TCS applications.

关键词： Triclosan Iron metabolism Hepcidin Hepatotoxicity Liver fibrosis

3D robust anisotropic diffusion filtering algorithm for sparse view neutron computed tomography 3D image reconstruction

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Nuclear Science and Techniques 2024年第3期35卷 13-29页

作者： Yang liu Teng-Fei Zhu Zhi Luo Xiao-ping Ouyang School of Nuclear Science and Engineering North China Electric Power UniversityBeijing 102206China State Key Laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang 330013China State Key Laboratory of Intense Pulsed Radiation Simulation and Effect Xi’an 710024China

The most critical part of a neutron computed tomography(NCT) system is the image processing algorithm,which directly affects the quality and speed of the reconstructed *** types of noise in the system can degrade the quality of the reconstructed ***,to improve the quality of the reconstructed images of NCT systems,efficient image processing algorithms must be *** anisotropic diffusion filtering(ADF) algorithm can not only effectively suppress the noise in the projection data,but also preserve the image edge structure information by reducing the diffusion at the image ***,we propose the application of the ADF algorithm for NCT image *** compare the performance of different algorithms in NCT systems,we reconstructed images using the ordered subset simultaneous algebraic reconstruction technique(OS-SART) algorithm with different regular terms as image processing *** the iterative reconstruction,we selected two image processing algorithms,the Total Variation and split Bregman solved total variation algorithms,for comparison with the performance of the ADF ***,the filtered back-projection algorithm was used for comparison with an iterative *** reconstructing the projection data of the numerical and clock models,we compared and analyzed the effects of each algorithm applied in the NCT *** on the reconstruction results,OS-SART-ADF outperformed the other algorithms in terms of denoising,preserving the edge structure,and suppressing *** example,when the 3D Shepp–Logan was reconstructed at 25 views,the root mean square error of OS-SART-ADF was the smallest among the four iterative algorithms,at only *** universal quality index,mean structural similarity,and correlation coefficient of the reconstructed image were the largest among all algorithms,with values of 0.9877,0.9878,and 0.9887,respectively.

关键词： NCT OS-SART Sparse-view Anisotropic diffusion filtering

Fine-grained grid computing model for Wi-Fi indoor localization in complex environments

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Journal of Electronic Science and Technology 2024年第1期22卷 42-52页

作者： Yan Liang Song Chen xin Dong Tu liu School of Computer Engineering Chengdu Technological UniversityChengdu611730China HAN Networks Corporation Limited Beijing100094China

The fingerprinting-based approach using the wireless local area network(WLAN)is widely used for indoor ***,the construction of the fingerprint database is quite *** when the position of the access point(AP)or wall changes,updating the fingerprint database in real-time is *** appropriate indoor localization approach,which has a low implementation cost,excellent real-time performance,and high localization accuracy and fully considers complex indoor environment factors,is preferred in location-based services(LBSs)*** this paper,we proposed a fine-grained grid computing(FGGC)model to achieve decimeter-level localization *** points(RPs)are generated in the grid by the FGGC ***,the received signal strength(RSS)values at each RP are calculated with the attenuation factors,such as the frequency band,three-dimensional propagation distance,and walls in complex *** a result,the fingerprint database can be established automatically without manual measurement,and the efficiency and cost that the FGGC model takes for the fingerprint database are superior to previous *** proposed indoor localization approach,which estimates the position step by step from the approximate grid location to the fine-grained location,can achieve higher real-time performance and localization accuracy *** mean error of the proposed model is 0.36 m,far lower than that of previous ***,the proposed model is feasible to improve the efficiency and accuracy of Wi-Fi indoor *** also shows high-accuracy performance with a fast running speed even under a large-size *** results indicate that the proposed method can also be suitable for precise marketing,indoor navigation,and emergency rescue.

关键词： Fine-grained grid computing (FGGC) Indoor localization Path loss Random forest Reference points(RPs)