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Blood glucose-lowering activity of protocatechuic acid is mediated by inhibiting a-glucosidase

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Food Science and Human Wellness 2024年第3期13卷 1212-1219页

作者： Huafang Ding Shouhe Huang chui Yiu Chook Erika Kwek Chi yan.Kaying Ma Jianhui Liu Hanyue Zhu Zhenyu Chen Food&Nutritional Sciences Programme School of Life SciencesThe Chinese University of Hong KongHong Kong 999077China

α-Glucosidase inhibitors are effective in controlling postprandial hyperglycemia,which play crucial roles in the management of type 2 *** acid(PCA)is one of phenolic acids existing not only in various plant foods but also as a major microbial metabolite of dietary anthocyan.ns in the large *** present study investigated the inhibitory mechanism of PCA on a-glucosidase in vitro and examined its effect on postprandial blood glucose levels in *** from in vitro experiments demonstrated that PCA was a mix-type inhibitor of *** by hydrogen bonds and van der Waals interactions,PCA reversibly bound withα-glucosidase to form a stable a-glucosidase-PCA complex in a spontaneous *** computational simulation found that PCA could insert into the active cavity of a-glucosidase and establish hydrogen bonds with catalytic amino acid *** binding aroused the steric hindrance for substrates to enter active sites and caused the structural changes of interacted catalytic amino acid *** also exhibited postprandial hypoglycemic capacity in diabetic *** study may provide the theoretical basis for the application of PCA as an active ingredient of functional foods in dietary management of diabetes.

关键词： Protocatechuic acid α-Glucosidase Postprandial hyperglycemia Inhibition mechanism

Nickel-catalyzed carbonylative four-component 1,4-dicarbofunctionalization of 1,3-enynes

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Science China Chemistry 2024年第6期67卷 2029-2038页

作者： yan.Zhao Qi-Chao Shan Hong Xin pin.Gao Xu yan. Xin-Hua Duan Li-Na Guo Department of Chemistry School of ChemistryXi’an Key Laboratory of Sustainable Energy Material Chemistry and Engineering Research Center of Energy StorageMaterials and DevicesMinistry of EducationXi’an Jiaotong UniversityXi’an710049China School of Electrical Engineering Xi’an Jiaotong UniversityXi’an710049China

An efficient Ni-catalyzed four-component 1,4-carbocarbonylation of 1,3-enynes with activated alkyl halides and arylboronic acids under atmospheric pressure of CO is *** tuning the electronic and steric effects of alkyl radicals,both electronrich and electron-deficient 1,3-enynes were compatible with this *** protocol features mild conditions,broad substrate scope,excellent functional group compatibility and facile gram-scale synthesis,providing a practical approach to the quaternary carbon center-containing allenyl *** study revealed that the acyl-NiIIspecies plays an important role in both the coupling and the alkyl radical generation processes.

关键词： Ni catalysis four-component 1 4-carbocarbonylation 1 3-enynes

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Intermittent fasting boosts antitumor immunity by restricting CD11b^(+)Ly6C^(low)Ly6G^(low) cell viability through glucose metabolism in murine breast tumor model

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Food Science and Human Wellness 2024年第4期13卷 2327-2345页

作者： Chenghao Fu Zhehao Liang Zemiao Niu Ning Chen Yuemin Li Zhenhua Liang yan.ei Huo Hao Xi Rong Wang Yonghuan yan.Xiaoruo Gan Mengtian Wang Yun Huang yan.Zhang Mingming Gao pin.Lü Postdoctoral Station for Basic Medicine Cardiovascular Medical Science CenterDepartment of Cell BiologyKey Laboratory of Neural and Vascular Biology of Ministry of EducationHebei Medical UniversityShijiazhuang 050017China Hebei Key Laboratory of Forensic Medicine College of Forensic MedicineHebei Medical UniversityShijiazhuang 050017China Hebei Food Safety Key Laboratory Hebei Food Inspection and Research InstituteShijiazhuang 050091China Laboratory of Lipid Metabolism Department of Biochemistry and Molecular BiologyKey Laboratory of Medical Biotechnology of Hebei ProvinceShijiazhuang 050017China

Intermittent fasting can benefit breast cancer patients undergoing chemotherapy or ***,it is still uncertain how to select immunotherapy drugs to combine with intermittent *** we observed that two cycles of fasting treatment significantly inhibited breast tumor growth and lung tissue metastasis,as well as prolonged overall survival in mice bearing 4T1 and 4T07 breast *** this process,both the immunosuppressive monocytic-(M-)and granulocytic-(G-)myeloid-derived suppressor cell(MDSC)decreased,accompanied by an increase in interleukin(IL)7R^(+)and granzyme B^(+)T cells in the tumor ***,we observed that Ly6G^(low)G-MDSC sharply decreased after fasting treatment,and the cell surface markers and protein mass spectrometry data showed potential therapeutic *** investigation revealed that glucose metabolism restriction suppressed the splenic granulocytemonocyte progenitor and the generation of colony-stimulating factors and IL-6,which both contributed to the accumulation of *** the other hand,glucose metabolism restriction can directly induce the apoptosis of Ly6G^(low)G-MDSC,but not Ly6G^(high)*** summary,these results suggest that glucose metabolism restriction induced by fasting treatment attenuates the immune-suppressive milieu and enhances the activation of CD3^(+)T cells,providing potential solutions for enhancing immune-based cancer interventions.

关键词： Intermittent fasting Ly6G^(low)myeloid-derived suppressor cell apoptosis Extramedullary hematopoiesis Colony stimulating factor Glucose metabolism restriction

General anesthetic agents induce neurotoxicity through astrocytes

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Neural Regeneration Research 2024年第6期19卷 1299-1307页

作者： yan.hang yan. Tiantian Liu Jun Li Dandan yan.Yuhan Hu pin.Wu Fuquan Fang Patrick M.McQuillan Wenxin Hang Jianhang Leng Zhiyong Hu Department of Anesthesiology The First Affiliated Hospital Zhejiang University School of Medicine Department of Anesthesiology Ningbo Women and Children's Hospital 3. Department of Anesthesiology Shulan (Hangzhou) Hospital Affiliated to Zhejiang Shuren University Shulan International Medical College 4. Cell Biology Department Yale University 5. Department of Anesthesiology Penn State Hershey Medical Centre Penn State College of Medicine 6. Department of Central Laboratory Affiliated Hangzhou First People's Hospital Zhejiang University School of Medicine

Neuroscientists have recognized the importance of astrocytes in regulating neurological function and their influence on the release of glial transmitters. Few studies, however, have focused on the effects of general anesthetic agents on neuroglia or astrocytes. Astrocytes can also be an important target of general anesthetic agents as they exert not only sedative, analgesic, and amnesic effects but also mediate general anesthetic-induced neurotoxicity and postoperative cognitive dysfunction. Here, we analyzed recent advances in understanding the mechanism of general anesthetic agents on astrocytes, and found that exposure to general anesthetic agents will destroy the morphology and proliferation of astrocytes, in addition to acting on the receptors on their surface, which not only affect Ca2+signaling, inhibit the release of brain-derived neurotrophic factor and lactate from astrocytes, but are even involved in the regulation of the pro-and anti-inflammatory processes of astrocytes. These would obviously affect the communication between astrocytes as well as between astrocytes and neighboring neurons, other neuroglia, and vascular cells. In this review, we summarize how general anesthetic agents act on neurons via astrocytes, and explore potential mechanisms of action of general anesthetic agents on the nervous system. We hope that this review will provide a new direction for mitigating the neurotoxicity of general anesthetic agents.

关键词： astrocytes brain-derived neurotrophic factor general anesthetic agents neuron neurotoxicity N-methyl-D-aspartate receptor perioperative neurocognition Toll-like receptor γ-aminobutyric acid receptor

Staging liver fibrosis with various diffusion-weighted magnetic resonance imaging models

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World Journal of Gastroenterology 2024年第9期30卷 1164-1176页

作者： yan.Li Jiang Juan Li Peng-Fei Zhang Feng-Xian Fan Jie Zou pin.yan. Peng-Fei Wang Shao-Yu Wang Jing Zhang Department of Magnetic Resonance Imaging The Second Hospital&Clinical Medical SchoolLanzhou UniversityLanzhou 730030Gansu ProvinceChina Second Clinical School Lanzhou UniversityLanzhou 730030Gansu ProvinceChina Gansu Province Clinical Research Center for Functional and Molecular Imaging The Second Hospital&Clinical Medical SchoolLanzhou UniversityLanzhou 730030Gansu ProvinceChina Department of Hepatology The Second Hospital&Clinical Medical SchoolLanzhou UniversityLanzhou 730030Gansu ProvinceChina MR Scientific Marketing Siemens HealthineersXi’an 710065Shaanxi ProvinceChina

BACKGROUND Diffusion-weighted imaging(DWI)has been developed to stage liver ***,its diagnostic performance is inconsistent among ***,it is worth studying the diagnostic value of various diffusion models for liver fibrosis in one *** To evaluate the clinical potential of six diffusion-weighted models in liver fibrosis staging and compare their diagnostic *** This prospective study enrolled 59 patients suspected of liver disease and scheduled for liver biopsy and 17 healthy *** participants underwent multi-b value *** main DWI-derived parameters included Mono-apparent diffusion coefficient(ADC)from mono-exponential DWI,intravoxel incoherent motion model-derived true diffusion coefficient(IVIM-D),diffusion kurtosis imaging-derived apparent diffusivity(DKI-MD),stretched exponential model-derived distributed diffusion coefficient(SEM-DDC),fractional order calculus(FROC)model-derived diffusion coefficient(FROC-D)and FROC model-derived microstructural quantity(FROC-μ),and continuous-time random-walk(CTRW)model-derived anomalous diffusion coefficient(CTRW-D)and CTRW model-derived temporal diffusion heterogeneity index(CTRW-α).The correlations between DWI-derived parameters and fibrosis stages and the parameters’diagnostic efficacy in detecting significant fibrosis(SF)were assessed and *** CTRW-D(r=-0.356),CTRW-α(r=-0.297),DKI-MD(r=-0.297),FROC-D(r=-0.350),FROC-μ(r=-0.321),IVIM-D(r=-0.251),Mono-ADC(r=-0.362),and SEM-DDC(r=-0.263)were significantly correlated with fibrosis *** areas under the ROC curves(AUCs)of the combined index of the six models for distinguishing SF(0.697-0.747)were higher than each of the parameters alone(0.524-0.719).The DWI models’ability to detect SF was *** combined index of CTRW model parameters had the highest AUC(0.747).CONCLUSION The DWI models were similarly valuable in distinguishing SF in patients with liver *** combined index of CTRW paramet

关键词： Liver fibrosis Magnetic resonance imaging Diffusion-weighted magnetic resonance Liver biopsy Significant fibrosis

Large eddy simulation study of 3D wind field in a complex mountainous area under different boundary conditions

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第7期25卷 541-556页

作者： yan.LI Lei yan.Xuhui HE School of Civil Engineering Central South UniversityChangsha410075China National Engineering Research Center for High-speed Railway Construction Changsha410075China Hunan Provincial Key Laboratory for Disaster Prevention and Mitigation of Rail Transit Engineering Structures Changsha410075China

Large eddy simulations generally are used to predict 3D wind field characteristics in complex mountainous *** simulation boundary conditions,such as the height and length of the computational domain or the characteristics of inflow turbulence,can significantly impact the quality of *** this study,we examined these boundary conditions within the context of the mountainous terrain around a long-span cable-stayed bridge using a wind tunnel *** sizes of computational domains and turbulent incoming wind velocities were used in large eddy *** results show that when the height of the computational domain is five times greater than the height of the terrain model,there is minimal influence from the top wall on the wind field characteristics in this complex mountainous *** the length of the wake region of the computational domain has negligible effects on the wind *** in the inlet boundary reduces the length of the wake region on a leeward hill with a low slope,but has less impact on the mean wind velocity of steep hills.

关键词： Large eddy simulation(LES) Spectral representation method Recycling method High mountainous canyon Wind characteristics Atmospheric boundary layer Computational domain

Towards Data-Driving Multi-View Evaluation Framework for Scratch

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Tsinghua Science and Technology 2024年第2期29卷 517-528页

作者： Xiaolin Chai yan.Sun yan.Gao Department of Computer Science Beijing University of Posts and TelecommunicationBeijing 100876China Intellectual Property Institute Shandong Polytechnic CollegeJining 272067China

As one of the most popular visual programming languages,Scratch has a lot of evaluation around *** evaluation can help programmers understand their projects *** the same time,it can also provide a reference for them to browse other projects in the online *** of the existing evaluations on Scratch are carried from three perspectives:Computational Thinking(CT)ability,visual presentation aesthetics,and code *** them,the assessment of CT and code quality is mainly carried out from the program script,while the evaluation of visual aesthetics is analyzed from the perspective of image sequences generated by project *** single-view evaluation focuses on the performance of a program in a certain aspect and is *** this paper,we propose a multi-view evaluation framework to integrate various evaluations using different *** quantitatively analyze the assessment of different views driven by *** with overall evaluations that represent human opin.ons,we analyze their differences and *** experiments,we determine the weights of different integration policies,the proposed multi-view evaluation method can generate evaluation results similar to human opin.ons.

关键词： Scratch Computational Thinking(CT) visual aesthetic static analysis integration policy machine learning

Forward to the Special Topic on“Solving Differential Equations with Deep Learning”

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Journal of Systems Science & Complexity 2024年第2期37卷 389-390页

作者： yan.Zhenya Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China

The concept of artificial intelligence(AI)was first presented at the Dartmouth SummerResearch Project on AI hosted by McCarthy and Minsky in *** that,the developmentof AI has experienced ups and downs due to some limited conditions including intelligentcomputing techniques,computer and hardware and software^([1,2]).In particular,with the rapidof deep artificial neural networks,machine learning(ML)and deep learning(DL)techniques^([3,4])have been applied in many fields of science and engineering,including machine translation,image recognition,genomics,scientific computing and atmospheric science,etc^([5]).

关键词： has artificial hardware

Electromagnetic characteristic analysis and design of a linear motor used for ultra-high-speed EMS maglev train

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Science China(Technological Sciences) 2024年第6期67卷 1957-1973页

作者： GAO Han SHI TingNa GAO XinMai LEI yan.iao yan.Dong GUO Liyan.yan.yan College of Electrical Engineering Zhejiang UniversityHangzhou310027China Zhejiang University Advanced Electrical Equipment Innovation Center Hangzhou311107China State Key Laboratory of High-speed Maglev Transportation Technology Qingdao266100China CRRC Qingdao Sifang Co.Ltd. Qingdao266111China

The operating speed of the commercial electromagnetic suspension(EMS)maglev train has been over 430 km/h,making it the fastest means of land *** the increasing demands of people traveling,it is necessary to further improve the operating speed of maglev *** to examine whether the existing EMS system can meet the requirements of ultra-highspeed operation(more than 600 km/h),the electromagnetic characteristics of an EMS linear motor under the operating speed of 600–1000 km/h fed by a square-wave voltage supply is investigated in this ***,an electromagnetic field model of the EMS system under the square-wave voltage supply is established to investigate its electromagnetic performance,e.g.,the characteristics of phase current,the magnetic flux density,and the electromagnetic ***,the relationship between the harmonic components of the air-gap magnetic flux density and electromagnetic force is investigated using the two-dimensional fast Fourier transform(2D-FFT)to reveal the mechanism of electromagnetic force ***,to address the issues of excessive armature current density and significant electromagnetic force ripple,the linear motor is re-designed by enlarging the stator slot area and reshapin. the mover's main magnetic ***,the Taguchi method is used to further improve the electromagnetic characteristics of the linear electric ***,the effectiveness of the proposed optimal design is validated by the finite-element analysis(FEA)based co-simulation.

关键词： ultra-high-speed maglev transportation electromagnetic suspension(EMS) linear motor electromagnetic force ripple suppression