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New cytotoxic apigenin derivatives from Selaginella doederleinii

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Chinese Chemical Letters 2017年第5期28卷 931-934页

作者： Zhen-Xing Zou Gui-Shan Tan guo-gang zhang Xia Yu Ping-Sheng Xu Kang-Ping Xu Xiangya Hospital of Central South University Changsha 410008China Xiangya School of Pharmaceutical Sciences Central South UniversityChangsha 410013China

75%aqueous ethanol extract from the whole herbs of Selaginella doederleinii was isolated,and two new apigenin derivatives,doederflavones A（1） and B（2）,together with ten known compounds（3-12） were characterized.Their structures were assigned by extensive spectroscopic methods including 1D/2D NMR and HR-ESIMS.Compounds 1-6 bear an aryl substituent at the C-8 or C-6 positions in ring A of apigenin skeleton.Compounds 1 and 2 were evaluated for their in vitro cytotoxicity against four human cancer cell lines A549,MCF-7,SMMC-7721,and LoVo,both of which exhibited significant cytotoxicity against A549 with IC50 values of 0.82 μmol/L and 1.32 μmol/L,respectively.

关键词： Apigenin derivatives Doederflavones A and B Cytotoxicity

Environmental enrichment in combination with Bifidobacterium breve HNXY26M4 intervention amplifies neuroprotective benefits in a mouse model of Alzheimer's disease by modulating glutamine metabolism of the gut microbiome

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Food Science and Human Wellness 2024年第2期13卷 982-992页

作者： Guangsu Zhu Min guo Jianxin Zhao Hao zhang gang Wang Wei Chen State Key Laboratory of Food Science and Resources Jiangnan UniversityWuxi 214122China School of Food Science and Technology Jiangnan UniversityWuxi 214122China (Yangzhou)Institute of Food Biotechnology Jiangnan UniversityYangzhou 225004China National Engineering Center of Functional Food Jiangnan UniversityWuxi 214122China

The gut microbiota-brain axis has emerged as a novel target for Alzheimer's disease(AD),a neurodegenerative disease characterised by behavioural and cognitive impairment.However,most previous microbiome-based intervention studies have focused on single factors and yielded only modest cognitive improvements.Here,we proposed a multidomain intervention strategy that combined Bifidobacterium breve treatment with environmental enrichment(EE)training.In this study,we found that compared with EE or B.breve treatment alone,B.breve intervention combined with EE amplified its neuroprotective effects on AD mice,as reflected by improved cognition,inhibited neuroinflammation and enhanced synaptic function.Moreover,using microbiome and metabolome profiling,we found that the combination of B.breve and EE treatment restored AD-related gut microbiota dysbiosis and reversed microbial metabolite changes.Finally,by integrating behavioural and neurological data with metabolomic profiles,we revealed that the underlying mechanism may involve the modulation of microbiota-derived glutamine metabolism via gut-brain interactions.Collectively,combined B.breve intervention with EE treatment can alleviate AD-related cognitive impairment and improve brain function by regulating glutamine metabolism of the gut microbiome.Our findings provide a promising multidomain intervention strategy,with a combination of dietary microbiome-based and lifestyle-targeted interventions,to promote brain function and delay the progression of AD.

关键词： Alzheimer’s disease Bifidobacterium breve Environmental enrichment Glutamine metabolism Microbiota-gut-brain axis

Mechanical properties and thermal deformation behavior of low-cost titanium matrix composites prepared by a structure-optimized Y_(2)O_(3) crucible

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Journal of Iron and Steel Research(International) 2024年第3期31卷 738-751页

作者： Qian Dang gang Huang Ye Wang Chi zhang guo-huai Liu Zhao-dong Wang The State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819LiaoningChina School of Materials Science and Chemical Engineering Harbin University of Science and TechnologyHarbin 150004HeilongjiangChina School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870LiaoningChina

A porous yttrium oxide crucible with both thermal shock resistance and erosion resistance was developed by structural optimization.The structure-optimized yttrium oxide crucible was proved to be suitable for melting highly reactive titanium alloys.Low-cost(TiB+Y2O_(3))-reinforced titanium matrix composites were prepared by vacuum induction melting using the prepared crucible.The thermal deformation behavior and microstructure evolution of(TiB+Y2O_(3))-reinforced tita-nium matrix composites were investigated at deformation temperatures of 900-1100℃with strain rates of 0.001-1 s-1.The results showed that the prepared yttrium oxide crucible had both thermal shock and erosion resistance,the low-cost titanium matrix composites could be prepared by the developed yttrium oxide crucibles which were homogeneous in composition and highly sensitive to strain rate and deformation temperature,and the peak and theological stresses decreased with increasing deformation temperature or decreasing strain rate.In addition,the average thermal deformation activation energy of the composites was calculated to be 574.6 kJ/mol by establishing the Arrhenius constitutive equation in consideration of the strain variables,and the fitting goodness between the predicted stress value and the measured value was 97.624%.The calculated analysis of the hot processing map showed that the best stable thermal deformation zone was located in the deformation temperature range of 1000-1100℃and strain rate range of 0.001-0.01 s^(-1),where the peak dissipation coefficient wasη=71%.In this zone,the deformation of the reinforcement and matrix was harmonious,the reinforcement was less likely to fracture,dynamic recrystallization occurred more fully and the alloy exhibited near steady rheological characteristics.

关键词： Yttrium oxide crucible Titanium matrix composite Thermal deformation behavior Constitutive equation Hot processing map Microstructure evolution

Classification of knowledge graph completeness measurement techniques

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Journal of Systems Engineering and Electronics 2024年第1期35卷 154-162页

作者： zhang Ying XIAO gang Institute of Systems Engineering Academy of Military SciencesBeijing 100107China

At present,although knowledge graphs have been widely used in various fields such as recommendation systems,question and answer systems,and intelligent search,there are always quality problems such as knowledge omissions and errors.Quality assessment and control,as an important means to ensure the quality of knowledge,can make the applications based on knowledge graphs more complete and more accurate by reasonably assessing the knowledge graphs and fixing and improving the quality problems at the same time.Therefore,as an indispensable part of the knowledge graph construction process,the results of quality assessment and control determine the usefulness of the knowledge graph.Among them,the assessment and enhancement of completeness,as an important part of the assessment and control phase,determine whether the knowledge graph can fully reflect objective phenomena and reveal potential connections among entities.In this paper,we review specific techniques of completeness assessment and classify completeness assessment techniques in terms of closed world assumptions,open world assumptions,and partial completeness assumptions.The purpose of this paper is to further promote the development of knowledge graph quality control and to lay the foundation for subsequent research on the completeness assessment of knowledge graphs by reviewing and classifying completeness assessment techniques.

关键词： quality assessment completeness assessment closed world assumptions open world assumption partial completeness assumption

Nanophononic metamaterials induced proximity effect in heat flux regulation

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Frontiers of physics 2024年第2期19卷 149-156页

作者： Jian zhang Haochun zhang gang zhang School of Energy Science and Engineering Harbin Institute of TechnologyHarbin 150001China Institute of High Performance Computing Agency for ScienceTechnology and Research(A*STAR)Singapore 138632Singapore

Recent studies have shown that the construction of nanophononic metamaterials can reduce thermal conductivity without affecting electrical properties,making them promising in many fields of application,such as energy conversion and thermal management.However,although extensive studies have been carried out on thermal conductivity reduction in nanophononic metamaterials,the local heat flux characteristic is still unclear.In this work,we construct a heat flux regulator which includes a silicon nanofilm with silicon pillars.The regulator has remarkable heat flux regulation ability,and various impacts on the regulation ability are explored.Surprisingly,even in the region without nanopillars,the local heat current is still lower than that in pristine silicon nanofilms,reduced by the neighboring nanopillars through the thermal proximity effect.We combine the analysis of the phonon participation ratio with the intensity of localized phonon modes to provide a clear explanation.Our findings not only provide insights into the mechanisms of heat flux regulation by nanophononic metamaterials,but also will open up new research directions to control local heat flux for a broad range of applications,including heat management,thermoelectric energy conversion,thermal cloak,and thermal concentrator.

关键词： nanophononic metamaterials proximity effect

Rational design of ZnCdS/TpPa-1-COF heterostructure photocatalyst by strengthening the interface connection in solar hydrogen production reactions

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Nano Research 2024年第3期17卷 1027-1034页

作者： Di Yang Zhi-gang Li Xinghao zhang Zenghuan Ren Weihan Lu Haining Liu Xiaomeng guo Jijie zhang Xian-He Bu Tianjin Key Laboratory of Metal and Molecule-Based Material Chemistry School of Materials Science and EngineeringNankai UniversityTianjin 300350China College of Chemistry and Pharmaceutical Engineering Hebei University of Science and TechnologyShijiazhuang 050018China State Key Laboratory of Elemento-Organic Chemistry College of ChemistryNankai UniversityTianjin 300071China

ZnCdS quantum dots(QDs)are highly coveted in photocatalysis research for their exceptional visible-light responses and high light-absorption coefficients.However,their practical application is hindered by their tendency to aggregate,due to having high surface energies.To address this issue,herein,a heterostructure is synthesized by growing ZnCdS QDs with a size of approximately 5 nm onto the surface of a two-dimensional(2D)covalent organic framework(COF),TpPa-1-COF.This approach suppresses the aggregation of the QDs and improves their stability.The ZnCdS/TpPa-1-COF composite exhibited a peak hydrogen evolution rate of 6244.16μmol·g^(-1)·h^(-1),which was 2.89 and 4.18 times greater than that of ZnCdS and TpPa-1-COF,respectively.The zero-dimensional/two-dimensional(0D/2D)heterojunction formed by ZnCdS and TpPa-1-COF generates a strong interfacial force,which is attributed to the intimate contact between the interfaces.Tight connections accelerate charge separation,improve the utilisation of reduced electrons,and reduce the extent of agglomeration of the ZnCdS QDs,thereby resulting in high hydrogen production activity of the composites.Meanwhile,the photocatalytic mechanism is studied using Kelvin probe force microscopy and theoretical calculations.This study offers a novel approach for creating sulfide photocatalysts and is crucial for investigating the potential practical applications of the related photocatalysts.

关键词： covalent organic frameworks quantum dots photocatalysis hydrogen generation heterojunction

A high-performance lithium anode based on N-doped composite graphene

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Rare Metals 2024年第3期43卷 1030-1036页

作者： Can Jiao Hao-Bo Sun Li zhang Shang-Qian Zhao guo-Yao Pang Chun-Rong Zhao Shi-gang Lu General Research Institute for Nonferrous Metals Beijing100088China China Automotive Battery Research Institute Co.Ltd Beijing101407China

Lithium(Li)metal is the most promising electrode for next-gene ration rechargeable batteries.In order to push the commercialization of the lithium metal batteries,a kind of nitrogen(N)-doped composite graphene(NCG)adopted as the Li plating host was prepared to regulate Li metal nucleation and suppress dendrite growth.Furthermore,a new kind of sandwich-type composite lithium metal(STCL)electrode was developed to improve its application.The STCL electrode can be used as convenient as a piece of Li foil but no dendrite growth.In a symmetric battery,the STCL electrode cycled for more than 4500 h with the overpotential of less than 40 mV.And due to the creative design,the STCL promises the Li-S battery with a prolonged cycling lifespan.

关键词： Lithium metal anode Lithiophilic N-doped composite graphene Sandwich-type composite lithium metal electrode

Color-kinematics duality and dual conformal symmetry for a four-loop form factor in N=4 SYM

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Science China(Physics,Mechanics & Astronomy) 2024年第4期67卷 64-71页

作者： Guanda Lin gang Yang Siyuan zhang CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUCASHangzhou 310024China International Centre for Theoretical Physics Asia-Pacific Beijing/Hangzhou 310024China

We obtain the integrand of full-color four-loop three-point form factor of the stress-tensor supermultiplet in N=4 SYM,based on the color-kinematics(CK)duality and generalized unitarity method.Our result not only manifests all dual Jacobi relations via CK duality but also contains 133 free parameters.This suggests the constructibility of the form factor at even higher loops via CK duality.We also find that the planar form factor has a hidden dual conformal symmetry in the lightlike limit of the operator momentum,which is checked up to four loops.

关键词： S-matrix supersymmetric model perturbative calculations

Myosteatosis is associated with coronary artery calcification in patients with type 2 diabetes

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World Journal of Diabetes 2024年第3期15卷 429-439页

作者： Fu-Peng Liu Mu-Jie guo Qing Yang Yan-Ying Li Yan-gang Wang Mei zhang The Affiliated Hospital of Medical College Qingdao University Qingdao UniversityQingdao 266071Shandong ProvinceChina Department of Endocrinology The Affiliated Hospital of Jining Medical UniversityJining 272029Shandong ProvinceChina Department of Medical Imaging The Affiliated Hospital of Jining Medical UniversityJining 272029Shandong ProvinceChina Department of Clinical Nutrition The Affiliated Hospital of Jining Medical UniversityJining 272029Shandong ProvinceChina Department of Endocrinology The Affiliated Hospital of Qingdao UniversityQingdao 266003Shandong ProvinceChina

BACKGROUND Myosteatosis,rather than low muscle mass,is the primary etiologic factor of sarcopenia in patients with type 2 diabetes mellitus(T2DM).Myosteatosis may lead to a series of metabolic dysfunctions,such as insulin resistance,systematic inflammation,and oxidative stress,and all these dysfunctions are closely associated with the acceleration of T2DM and atherosclerosis.AIM To investigate the association between myosteatosis and coronary artery calcification(CAC)in patients with T2DM.METHODS Patients with T2DM,who had not experienced major cardiovascular events and had undergone both abdominal and thoracic computed tomography(CT)scans,were included.The mean skeletal muscle attenuation was assessed using abdominal CT images at the L3 level.The CAC score was determined from thoracic CT images using the Agatston scoring method.Myosteatosis was diagnosed according to Martin’s criteria.Severe CAC(SCAC)was defined when the CAC score exceeded 300.Logistic regression and decision tree analyses were performed.RESULTS A total of 652 patients with T2DM were enrolled.Among them,167(25.6%)patients had SCAC.Logistic regression analysis demonstrated that myosteatosis,age,duration of diabetes,cigarette smoking,and alcohol consumption were independent risk factors of SCAC.Myosteatosis was significantly associated with an increased risk of SCAC(OR=2.381,P=0.003).The association between myosteatosis and SCAC was significant in the younger patients(OR=2.672,95%CI:1.477-4.834,P=0.002),but not the older patients(OR=1.456,95%CI:0.863-2.455,P=0.188),and was more prominent in the population with lower risks of atherosclerosis.The decision tree analyses prioritized older age as the primary variable for SCAC.In older patients,cigarette smoking was the main contributing factor for SCAC,while in younger patients,it was myosteatosis.CONCLUSION Myosteatosis is a novel risk factor for atherosclerosis in patients with T2DM,especially in the population with younger ages and fewer traditional risk factors.

关键词： Type 2 diabetes Myosteatosis Muscle quality Coronary artery calcification Atherosclerosis Cardiovascular diseases