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Improving antioxidant activities of water-soluble lignin-carbohydrate complex isolated from wheat stalk through prolonging ball-milling pretreatment and homogeneous extraction

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Journal of Bioresources and Bioproducts 2024年第1期9卷 113-125页

作者： di Xie Zhulan Liu yunfeng Cao Sheng-I Yang chen Su Mi Li Jiangsu Co-innovation Center for Efficient Processing and Utilization of Forest Products Nanjing Forestry UniversityNanjing 210037China International Innovation Center for Forest Chemicals and Materials Nanjing Forestry UniversityNanjing 210037China Center for Renewable Carbon School of Natural ResourcesUniversity of TennesseeKnoxvilleTN 37996USA Shandong Huatai Paper Co. Ltd.Dongying 257000China School of Natural Resources University of TennesseeKnoxvilleTN 37996USA Key Lab of Biomass Energy and Material Institute of Chemical Industry of Forest ProductsChinese Academy of ForestryJiangsu ProvinceNanjing 210042China

Water-soluble lignin-carbohydrate complex(LCC)rich in polysaccharides exhibits benign in vitro antioxidant activities and distinguishes high biocompatibility from lignin-rich LCC and ***,the antioxidant activity of water-soluble LCCs remains to be improved and its structure-antioxidant relationship is still ***,structurally diversified water-soluble LCCs were isolated under different ball-milling pretreatment durations(4,6,8 h),extraction pathways(ho-mogeneous and heterogeneous),and isolation routines(water extracts and residues after water extraction).Their structures were characterized by wet chemistry,chromatography and *** activities were evaluated by ferric reducing antioxidant power and 1,1-diphenyl-2-picrylhydrazyl radicals scavenging rate(RDPPH).Results show that altering ball-milling duration and isolation procedures cause varied structures and antioxidant activities of the water-soluble ***,prolonging ball-milling duration to 8 hours and homogeneous extrac-tion can enhance their antioxidant activity through releasing more phenolic structures and pro-moting the extraction of high-molecular-weight LCCs via reducing mass-transfer resistance,*** a result,the RDPPH of water-soluble LCCs reaches up to 97.35%,which is associated with the arabinan content with statistical significance(P<0.05).This study provides new insights into the structure-antioxidation relationship of herbaceous LCC as potential antioxidants.

关键词： LCC Homogeneous extraction Ball-milling Structure-antioxidation relationship Wheat straw

Evaluation and attribution of trends in compound dry-hot events for major river basins in China

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Science China Earth Sciences 2024年第1期67卷 79-91页

作者： Shaotang XIONG Tongtiegang ZHAO chengchao GUO yu TIAN Fang YANG Wenlong chen Xiaohong chen Key Laboratory of Water Security Guarantee in Guangdong-Hong Kong-Marco Greater Bay Area of Ministry of Water Resources&Sun Yatsen University/Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Guangzhou 510275China China Institute of Water Resource and Hydropower Research Beijing 100038China Pearl River Hydraulic Research Institute Guangzhou 510611China

Concurrent compound dry and hot events(CDHEs)amplified more damange on the ecosystems and human society than individual *** climate change,compound dry and hot events become more frequent on a global *** paper proposes a mathematical method to quantitatively attribute changes of CDHEs to changes of precipitation,change in temperature and change in the dependence between precipitation and *** attribution is achieved by formulating the total differential equation of the return period of CDHEs among Meta-gaussian model.A case study of China is devised based on monthly precipitation and temperature data during the period from 1921 to 2020 for 80 major river *** is found that temperature is the main driving factor of increases in CDHEs for 49 major river basins in China,except for the upper and middle reaches of the Yangtze *** West China,precipitation changes drove the increase in CDHEs in 18 river basins(23%),particularly in parts of North Xinjiang,Qinghai and *** the other hand,dependence between precipitation and temperature dominated changes of CDHEs in 13 river basins(16%)of China with other factors,including parts of South China,East China and Northwestern ***,changes in both the mean and spread of precipitation and temperature can also contribute to changes in CDHEs.

关键词： Climate extreme Compound dry and hot extreme Precipitation Temperature Return period

Swelling of Spherical Polyelectrolyte Gels

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Chinese Journal of Polymer Science 2024年第9期42卷 1386-1392,I0009页

作者： Ming-yu Duan Jia-Dong chen Yi-Ming Liu Zhao-Feng Peng Guang chen Department of Advanced Manufacturing and Robotics College of EngineeringPeking UniversityBeijing 100871China

Polyelectrolyte(PE)gels,distinguished by their unique stimuli-responsive swelling behavior,serve as the basis of broad applications,such as artificial muscles and drug *** this work,we present a theoretical model to analyze the electrostatics and its contribution to the swelling behavior of PE gels in salt *** minimizing the free energy of PE gels,we obtain two distinct scaling regimes for the swelling ratio at equilibrium with respect to the salt *** compare our predictions for the swelling ratio with experimental measurements,which show excellent *** addition,we employ a finite element method to assess the applicability range of our theoretical model and *** anticipate that our model will also provide valuable insights into drug adsorption and release,deformation of red blood cells,4D printing and soft robotics,where the underlying mechanism of swelling remains enigmatic.

关键词： Gels Polyelectrolytes Swelling Stimuli-responsive Electrostatic interaction Cell model

Carbon nanotubes-reinforced polylactic acid/hydroxyapatite porous scaffolds for bone tissue engineering

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Frontiers of Materials Science 2024年第1期18卷 59-69页

作者： Weiwei Lan Mingbo Wang Zhenjun Lv Jun Li Fuying chen Ziwei Liang di Huang Xiaochun Wei Weiyi chen Research Center for Nano-Biomaterials&Regenerative Medicine Department of Biomedical EngineeringCollege of Biomedical EngineeringTaiyuan University of TechnologyTaiyuan 030024China Guangdong Engineering Technology Research Center of Implantable Medical Polymer Shenzhen Lando Biomaterials Co.Ltd.Shenzhen 518107China Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering Taiyuan 030060China Department of Orthopaedics The Second Hospital of Shanxi Medical UniversityTaiyuan 030001China

In the field of bone defect repair,critical requirements for favorable cytocompatibility and optimal mechanical properties have propelled research efforts towards the development of composite *** this study,carbon nanotubes/polylactic acid/hydroxyapatite(CNTs/PLA/HA)scaffolds with different contents(0.5,1,1.5 and 2 wt.%)of CNTs were prepared by the thermally induced phase separation(TIPS)*** results revealed that the composite scaffolds had uniform pores with high porosities over 68%and high through *** addition of CNTs significantly enhanced the mechanical properties of resulted PLA/HA,in which the 1.5 wt.%CNTs/PLA/HA composite scaffold demonstrated the optimum mechanical behaviors with the bending elastic modulus of(868.5±12.34)MPa,the tensile elastic modulus of(209.51±12.73)MPa,and the tensile strength of(3.26±0.61)***,L929 cells on the 1.5 wt.%CNTs/PLA/HA scaffold displayed good spreading performance and favorable ***,it is expected that the 1.5 wt.%CNTs/PLA/HA scaffold has potential applications in bone tissue engineering.

关键词： CNTs/PLA/HA scaffold TIPS method mechanical property bone tissue engineering

Vitamin A deficiency suppresses CEACAM1 to impair colonic epithelial barrier function via downregulating microbial-derived short-chain fatty acids

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Genes & diseases 2024年第2期11卷 1066-1081页

作者： Junyan Yan Lu Xiao di Feng Baolin chen Ting Yang Bei Tong Ruifang Luo yuting Wang Jie chen Children Nutrition Research Center Children's Hospital of Chongqing Medical UniversityChongqing Key Laboratory of Child Nutrition and HealthMinistry of Education Key Laboratory of Child Development and DisordersNational Clinical Research Center for Child Health and DisordersChongqing 401122China Department of Gastroenterology Children's Hospital of Chongqing Medical UniversityChongqing 401122China

Vitamin A (VA) plays an essential role in modulating both the gut microbiota and gut barrier ***-chain fatty acids (SCFAs),as metabolites of the gut microbiota,protect the physiological intestinal barrier;however,they are compromised when VA is ***,there is an urgent need to understand how and which SCFAs modulate colonic epithelial barrier integrity in VA deficiency (VAD).Herein,compared with normal VA rats (VAN),at the beginning of pregnancy,we confirmed that the colonic desmosome junction was impaired in the VAD group,and the amounts of acetate,propionate,and butyrate declined because of the decreased abundance of SCFA-producing bacteria (Romboutsia ,Collinsella ,and Allobaculum ).The differentially expressed genes correlated with the gut barrier and the histone deacetylase complex between the VAD and VAN groups were enriched by RNA *** the VAD group,the expression levels of colonic CEA cell adhesion molecule 1 (CEACAM1) were down-regulated,and the levels of histone deacetylase 1 (HDAC1) and HDAC3 were ***,the above changes in the VAD groups were rescued by VA supplementation in the early postnatal *** study indicated that in Caco-2 cells,butyrate treatment significantly repressed the enrichment of HDAC3 on the promoter of the CEACAM1 gene to induce its *** findings support that butyrate intervention can alleviate the impairment of colonic barrier function caused by VAD,and timely postnatal VA intervention may reverse the damage caused by VAD on gut barrier integrity during pregnancy.

关键词： CEACAM1 Colonic epithelial barrier HDAC3 Short-chain fatty acids Vitamin A deficiency

Interregional Value-Added Tax in the Era of E-Commerce: Tax Policy Design Based on Big Data from Online Retailing

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Journal of Social Computing 2024年第1期5卷 46-57页

作者： yu chen Luwei Xiang Hu Yang School of Public Finance and Taxation Central University of Finance and EconomicsBeijing 100008China School of Management and Economics The Chinese University of Hong KongShenzhen 518172China School of Information Central University of Finance and EconomicsBeijing 100008China

The value-added tax(VAT)in China is levied and allocated based on the origin *** the background of the increasing substitution of online retail for traditional offline retail,this mechanism will exacerbate the disparity of regional tax revenue,and intensify tax competition among local ***,reconsidering the allocation mechanism of value-added tax in China can be an important policy decision,and it is influenced by various economic and social ***,we utilize large-scale retail transaction data from an e-commerce platform to measure regional disparities in retail and consumption among different regions and then reveals present tax policy results in revenue imbalance in different ***,we establish a model based on game theory to illustrate how the origin principle leads to fierce tax competition among ***,by establishing and solving tax allocation models between local governments and the central government,this study simulates and calculates the degree of revenue imbalance under different scenarios and attempts to propose policy *** results indicate that implementing the destination principle will reduce regional tax ***,adjusting the allocation ratio between the central government and local governments based on city levels is advantageous for further reducing regional tax revenue disparities.

关键词： value-added tax e-commerce destination principle origin principle

Impact of baseline hepatitis B virus viral load on the long-term prognosis of advanced hepatocellular carcinoma treated with immunotherapy

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World Journal of Gastrointestinal Oncology 2024年第6期16卷 2504-2519页

作者： di Pan Hao-Nan Liu Zhi-yuan Yao Xiao-Xiao chen yu-Qi Li Jing-Jing Zhu Zheng-Xiang Han Xiao-Bing Qin Department of Oncology The Affiliated Hospital of Xuzhou Medical UniversityXuzhou 221000Jiangsu ProvinceChina

BACKGROUND Although the combination of lenvatinib and PD-1 inhibitors has become the standard regimen for the treatment of advanced hepatocellular carcinoma(HCC),real data on the impact of baseline hepatitis B virus(HBV)-DNA levels on the clinical efficacy of this regimen is still *** To evaluate the effectiveness of camrelizumab combined with lenvatinib in patients with HCC at varying levels of *** One hundred and twenty patients with HCC who received camrelizumab and lenvatinib treatment were categorized into two cohorts:HBV-DNA≤2000(n=66)and HBV-DNA>2000(n=54).The main outcomes measured were overall survival(OS)and progression-free survival(PFS),while additional outcomes included the rate of objective response rate(ORR),disease control rate(DCR),and any negative *** proportional hazards regression analysis revealed independent predictors of OS,leading to the creation of a nomogram incorporating these *** The median PFS was 8.32 months for the HBV-DNA≤2000 group,which was similar to the 7.80 months observed for the HBV DNA>2000 group(P=0.88).Likewise,there was no notable variation in the median OS between the two groups,with durations of 13.30 and 14.20 months respectively(P=0.14).The ORR and DCR were compared between the two groups,showing ORR of 19.70%vs 33.33%(P=0.09)and DCR of 72.73%vs 74.07%(P=0.87).The nomogram emphasized the importance of antiviral treatment as the main predictor of patient results,with portal vein tumor thrombus and Barcelona Clinic Liver Cancer staging following closely *** The clinical outcomes of patients with HBV-associated HCC treated with camrelizumab in combination with lenvatinib are not significantly affected by HBV viral load.

关键词： Hepatitis B virus Hepatocellular carcinoma Camrelizumab Lenvatinib Efficacy

Broadband and fabrication-tolerant 3-dB couplers with topological valley edge modes

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Light(Science & Applications) 2024年第8期13卷 1623-1630页

作者： Guo-Jing Tang Xiao-Dong chen Lu Sun Chao-Heng Guo Meng-yu Li Zhong-Tao Tian Hou-Hong chen Hong-Wei Wang Qi-Yao Sun Ying-di Pan Xin-Tao He Yi-Kai Su Jian-Wen Dong School of Physics&State Key Laboratory of Optoelectronic Materials and Technologies Sun Yat-sen UniversityGuangzhou 510275China State Key Laboratory of Advanced Optical Communication Systems and Networks Department of Electronic EngineeringShanghai Jiao Tong UniversityShanghai 200240China

3-dB couplers,which are commonly used in photonic integrated circuits for on-chip information processing,precision measurement,and quantum computing,face challenges in achieving robust performance due to their limited 3-dB bandwidths and sensitivity to fabrication *** address this,we introduce topological physics to nanophotonics,developing a framework for topological 3-dB *** couplers exhibit broad working wavelength range and robustness against fabrication dimensional *** leveraging valley-Hall topology and mirror symmetry,the photonic-crystal-slab couplers achieve ideal 3-dB splitting characterized by a wavelength-insensitive scattering *** analysis confirms the superiority on broad bandwidth of 48 nm and robust splitting against dimensional errors of 20 *** further propose a topological interferometer for on-chip distance measurement,which also exhibits robustness against dimensional *** extension of topological principles to the fields of interferometers,may open up new possibilities for constructing robust wavelength division multiplexing,temperature-drift-insensitive sensing,and optical coherence tomography applications.

关键词： topological splitting insensitive

Unveiling the secrets of diatom-mediated calcification:Implications for the biological pump

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Science China Earth Sciences 2024年第9期67卷 2895-2909页

作者： Yiwen PAN Yifan LI chen-Tung Arthur chen Zong-Pei JIANG Wei-Jun CAI yunwen SHEN Zesheng diNG Qixian chen Yanan di Wei FAN chenba ZHU Ying chen Ocean College Zhejiang UniversityZhoushan 316021China Hainan Institute of Zhejiang University Sanya 570203China Department of Oceanography Sun Yat-Sen UniversityGaoxiong 80424China School of Marine Science and Policy University of DelawareNewark DE 19716USA Carbon Neutral Innovation Research Center Xiamen UniversityXiamen 361005China

Siliceous diatoms are one of the most prominent actors in the oceans,and they account for approximately 40%of the primary production and particulate organic carbon export *** is believed that changes in carbon flux caused by variations in diatom distribution can lead to significant climate *** the fundamental pathways of diatom-driven carbon sequestration have long been established,there are no reports of CaCO_(3) precipitation induced by marine diatom *** manuscript introduces novel details regarding the enhancement of aragonite precipitation during photosynthesis in Skeletonema costatum in both artificial and natural *** direct measurements of cell surfaces via a pH microelectrode and zeta potential analyzer,it was determined that the diatom-mediated promotion of CaCO_(3) precipitation is achieved through the creation of specific microenvironments with concentrated[CO_(3)^(2-)]and[Ca^(2+)]and/or the dehydrating effect of adsorbed Ca^(2+).Based on this mechanism,it is highly plausible that diatom-mediated calcification could occur in the oceans,an assertion that was supported by the significant deviation of total alkalinity(TA)from the conservative TA-salinity mixing line during a Skeletonema costatum bloom in the East China Sea and other similar *** newly discovered calcification pathway establishes a link between particulate inorganic and organic carbon flux and thus helps in the reassessment of marine carbon export fluxes and CO_(2) sequestration *** discovery may have important ramifications for assessing marine carbon cycling and predicting the potential effects of future ocean acidification.

关键词： diatom bloom Skeletonema costatum Calcification Biological carbon pump Counter carbonate pump