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Enhanced detection of freeze‒thaw induced landslides in Zhidoi county(Tibetan Plateau,China)with Google Earth Engine and image fusion

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Advances in Climate Change Research 2024年第3期15卷 476-489页

作者： Jia-Hui YANG Yan-Chen gao Lang JIA Wen-Juan WANG qing-Bai WU Francis ZVOMUYA Miles DYCK hai-Long HE College of Natural Resources and Environment Northwest A&F UniversityYangling 712100China State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Department of Soil Science University of Manitob1Winnipeg MB R3T 2N2Canada Department of Renewable Resources University of Albert1Edmonton AB T6G 2H1Canad

Freeze‒thaw induced landslides(FTILs)in grasslands on the Tibetan Plateau are a geological disaster leading to soil *** landslides reduce biodiversity and intensify landscape fragmentation,which in turn are strengthen by the persistent climate change and increased anthropogenic ***,conventional techniques for mapping FTILs on a regional scale are impractical due to their labor-intensive,costly,and time-consuming *** study focuses on improving FTILs detection by implementing image fusion-based Google Earth Engine(GEE)and a random forest *** of multiple data sources,including texture features,index features,spectral features,slope,and vertical‒vertical polarization data,allow automatic detection of the spatial distribution characteristics of FTILs in Zhidoi county,which is located within the qinghai‒Tibet Engineering Corridor(QTEC).We employed statistical techniques to elucidate the mechanisms influencing FTILs *** enhanced method identifies two schemes that achieve high accuracy using a smaller training sample(scheme A:94.1%;scheme D:94.5%)compared to other methods(scheme B:50.0%;scheme C:95.8%).This methodology is effective in generating accurate results using only~10%of the training sample size necessitated by other *** spatial distribution patterns of FTILs generated for 2021 are similar to those obtained using various other training sample sources,with a primary concentration observed along the central region traversed by the *** results highlight the slope as the most crucial feature in the fusion images,accounting for 93%of FTILs occurring on gentle slopes ranging from 0°to 14°.This study provides a theoretical framework and technological reference for the identification,monitoring,prevention and control of FTILs in *** developments hold the potential to benefit the management of grassland ecosystem,reduce economic losses,and promote grassland sustainability.

关键词： Permafrost degradation Random forest Thaw slump Spatial distribution Tibetan Plateau

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Dual template-induced construction of three-dimensional porous SiO2/NC/Co-CNTs heterostructure with highly dispersed active sites for efficient oxygen evolution reaction

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Tungsten 2024年第3期6卷 585-595页

作者： hai-Qi Zhang Xiao-Jun Zeng qing-qing Zhang Zu-Liang Zhang Chu-Long Jin Rong-hai Yu School of Materials Science and Engineering Jingdezhen Ceramic University School of Materials Science and Engineering Beihang University

The development and exploration of efficient and economical electrocatalysts for oxygen evolution reaction（OER） represents the main bottleneck to unlocking a sustainable energy scenario based on elec trocataly tic water *** scale integration of three-dimensional（3D） porous heterostructure with highly dispersed active sites and good structural stability is ***,a dual template route is developed to construct the 3D porous SiO2/nitrogen-doped carbon（NC）/Co-carbon nano tubes（CNTs） hetero ***,the hard template（SiO2nano spheres） contributes to 3D porous structure,increases the specific surface area,and promotes the contact area of the *** the same time,the soft template（basic zinc carbonate） can control the growth of 1D CNTs and facilitate the exposure of the active ***,3D porous SiO2/NC/Co-CNTs hetero structure inherits highly dispersed Co nanoparticles coated by *** conductive channels and abundant N hetero atoms doping are reasonably constructed by a dual template ***,SiO2/NC/Co-CNTs catalyst provides an extraordinary activity for the OER in alkaline media,with a low overpotential of 298 mV at a current density of 10 mA·***,SiO2/NC/Co-CNTs hetero structure enables excellent long-term durability with a 10 mV decay in overpotential after 3000 cyclic voltammetry cycles,and 97% remain in current density over 20 *** is believed that this dual template strategy can provide a new and simple way to construct a highly dispersed active site in electrocatalysts.

关键词： Dual template High dispersion Porous heterostructure Conductive channels Oxygen evolution reaction

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A Study on the Impact of Chemical Structure on the Evolution of Aggregate Structure in Fiber-shaped High Density Polyethylene Vitrimer

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Chinese Journal of Polymer Science 2024年第10期42卷 1557-1565,I0013页

作者： Bing Wang Yuan-Chu gao hai Wang Hui Niu State Key Laboratory of Fine Chemicals School of Chemical EngineeringDalian University of TechnologyDalian116024China

Vitrimers have emerged as a prominent research area in the field of polymer *** of the studies have focused on synthesizing polymers with versatile dynamic crosslinking structures,while the impact of chemical structure on aggregate structure of vitrimers,particularly during polymer processing,remains insufficiently *** present study employed commercial maleic anhydride-grafted-high density polyethylene(M-g-HDPE)as the matrix and hexanediol as the crosslinker to facilely obtain fiber-shaped HDPE vitrimers through a reaction extrusion and post-drawing *** chemical structure characterization,morphology observation,thermal and mechanical properties investigation,as well as aggregate structure analysis,this work revealed the influence of dynamic bonds on the formation of aggregate structures during fiber-shaped vitrimers processing.A small amount of dynamic bonds in HDPE restricts the motion of PE chain during melt-extruding and post-drawing,resulting in a lower orientation of the PE ***,lamellar growth and fibril formation during post-drawing at high temperature are enhanced to some extent due to the competition between dynamic bond and chain *** uneven morphology of fibershaped HDPE vitrimers can be attributed to the stronger elastic effect brought by dynamic bonding,which plays a more dominant role in determining the mechanical properties of fiber-shaped vitrimers compared to aggregate *** Vitrimers have emerged as a prominent research area in the field of polymer *** of the studies have focused on synthesizing polymers with versatile dynamic crosslinking structures,while the impact of chemical structure on aggregate structure of vitrimers,particularly during polymer processing,remains insufficiently *** present study employed commercial maleic anhydride-grafted-high density polyethylene(M-g-HDPE)as the matrix and hexanediol as the crosslinker to facilely obtain fiber-shap

关键词： High density polyethylene vitrimer Fiber-shaped Aggregate structures Transesterification reaction

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Effects of phlorizin on vascular complications in diabetes db/db mice

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Chinese Medical Journal 2012年第20期125卷 3692-3696页

作者： SHEN Lin YOU Bei-an gao hai-qing LI Bao-ying YU Fei PEI Fei Department of Geriatrics Qilu Hospital of Shandong UniversityJinanShandong 250012China

Background Diabetic macrovascular complications are important causes of cardiovascular and cerebrovascular diseases and also one of the major causes of morbidity and mortality in patients with type 2 diabetes mellitus （T2DM）. Phlorizin has been reported to be effective in reducing the blood glucose level in diabetic mellitus, while little is known about its effects on vascular complications. This study aimed to observe the effects of phlorizin on the aorta of diabetes db/db mice and explore its mechanism. Methods Diabetic db/db mice （n=16） and age-matched db/m mice （n=8） were divided into three groups： normal control group （CC group, db/m mice, n=8）, untreated diabetic group （DM group, db/db mice, n=8） and diabetic group treated by phlorizin （DMT group, db/db mice, n=8）. Phlorizin （20 mg/kg body weight） was given in normal saline solution intragastrically for 10 weeks. Animals were weighed weekly. At the 10th weekend, all mice were fasted overnight and then sacrificed. Fasting blood was collected, and the aortas were dissected. The blood samples were analyzed for fasting blood glucose （FBG）, serum advanced glycation end products （AGEs）, malondialdehyde （MDA） and superoxide dismutase （SOD） activity, the aortic ultrastructure was studied. Results The weight and serum concentration of FBG, AGEs, and MDA in the DM group were higher than that in the CC group （P 〈0.01 ）, and they were significantly lower in the DMT group （P 〈0.05）. Serum SOD activity was lower than that in the CC group （P 〈0.01）, and it is significantly higher in the DMT group （P 〈0.05）. The severity of aorta damage in the DMT group was less than that in the DM group. Conclusions Phlorizin protected the db/db mice from diabetic macrovascular complications, attributed to the decreasing of blood glucose and AGEs level, and its antioxidant potential. This study may provide a new natural medicine for treating diabetic macrovascular complications.

关键词： diabetes mellitus, type 2," phlorizin macrovascular complications db/db mice," oxidative stress

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Molecular mechanism of a coastal cyanobacterium Synechococcus *** 7002 adapting to changing phosphate concentrations

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Marine Life Science & Technology 2024年第3期6卷 562-575页

作者： Qiao-Wei Sun Yu gao Jordan Wang Fei-xue Fu Cheng-Wen Yong Shuang-qing Li hai-Long Huang Wei-Zhong Chen Xin-Wei Wang hai-Bo Jiang School of Marine Sciences Ningbo UniversityNingbo 315211China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519080China School of Life Sciences Central China Normal UniversityWuhan 430079China Department of Biological Sciences University of Southern CaliforniaLos AngelesCA 90089USA

Phosphorus concentration on the surface of seawater varies greatly with different environments,especially in *** molecular mechanism by which cyanobacteria adapt to fluctuating phosphorus bioavailability is still *** this study,transcriptomes and gene knockouts were used to investigate the adaptive molecular mechanism of a model coastal cyanobacterium Synechococcus *** 7002 during periods of phosphorus starvation and phosphorus recovery(adding sufficient phosphorus after phosphorus starvation).The findings indicated that phosphorus deficiency affected the photosynthesis,ribosome synthesis,and bacterial motility pathways,which recommenced after phosphorus was *** more,most of the metabolic pathways of cyanobacteria were enhanced after phosphorus recovery compared to the control which was kept in continuous phosphorus replete *** on transcriptome,54 genes potentially related to phosphorusdeficiency adaptation were selected and knocked out individually or in *** was found that five mutants showed weak growth phenotype under phosphorus deficiency,indicating the importance of the genes(A0076,A0549-50,A1094,A1320,A1895)in the adaptation of phosphorus *** mutants were found to grow better than the wild type under phosphorus deficiency,suggesting that the products of these genes(A0079,A0340,A2284–86)might influence the adaptation to phosphorus *** analysis revealed that cyanobacteria exposed to highly fluctuating phosphorus concentrations have more sophisticated phosphorus acquisition *** results elucidated that Synechococcus *** 7002 have variable phosphorus response mechanisms to adapt to fluctuating phosphorus concentration,providing a novel perspective of how cyanobacteria may respond to the complex and dynamic environments.

关键词： Synechococcus sp PCC 7002 Phosphorus fluctuation Cyanobacteria ・Gene knockout Molecular mechanism

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Room-temperature phonon-coupled single-photon emission in hexagonal boron nitride

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Science China(Physics,Mechanics & Astronomy) 2024年第5期67卷 109-114页

作者： Jia-Min Lai qing-hai Tan Feilong Song Haonan Chang Yanpei Lv Xue-Lu Liu Jinghua Teng Weibo gao Ping-Heng Tan Jun Zhang State Key Laboratory of Superlattices and Microstructures Institute of SemiconductorsChinese Academy of SciencesBeijing100083China Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education&Research Institute of Materials Science Shanxi Normal UniversityTaiyuan 030000China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Division of Physics and Applied Physics School of Physical and Mathematical SciencesNanyang Technological UniversitySingapore 637371Singapore Institute of Materials Research and Engineering(IMRE) Agency for ScienceTechnology and Research(A*STAR)Singapore 138634Singapore

Photon-lattice(phonon)coupling is fundamental to light-matter interaction,particularly when it reaches the quantum limit of the phonon-coupled single-photon emission,which holds great potential for quantum manipulation and quantum information ***,we report single defect state-phonon coupling in hexagonal boron nitride(h BN)at room *** ultrabroad spectrum of single-photon emissions can be achieved by selecting the excitation *** photoluminescence excitation spectroscopy,we observe single-phonon-assisted resonance-enhanced single-photon emission,along with multiple phonon replicas that herald the creation of phonon Fock *** also develop a transition model to gain insight into the physical process behind the single defect state-phonon *** work sets the stage for manipulating electron-phonon coupling state with single quantum-level precision at room temperature.

关键词： temperature phonon hexagonal

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New First-line Immunotherapy-based Therapies for Unresectable Hepatocellular Carcinoma: A Living Network Meta-analysis

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Journal of Clinical and Translational Hepatology 2024年第1期12卷 15-24页

作者： Jian-Jian Chen Zhi-Cheng Jin Biao Luo Yu-qing Wang Rui Li hai-Dong Zhu gao-Jun Teng Center of Interventional Radiology&Vascular Surgery Department of RadiologyZhongda HospitalMedical SchoolSoutheast UniversityNanjingJiangsuChina

Background and Aims:Several first-line immune checkpoint inhibitor(ICI)-based combination therapies have been identified for unresectable hepatocellular carcinoma(uHCC).This network meta-analysis(NMA)aimed to provide the most updated evidence about the preferred first-line ICI-based regimens for ***:A comprehensive literature search was performed in various databases from database inception to May *** phase 3 trials evaluating first-line single-agent ICIs,molecular-target agents(MTAs),or their combinations in uHCC were *** main endpoints were overall survival(OS)and progression-free survival(PFS).Pooled effect estimates were calculated using a random effects model within the frequentist *** analyses based on etiology were also ***:Twelve trials at low risk of bias with 8,275 patients comparing 13 treatments were *** with atezolizumab plus bevacizumab was comparable to sintilimab plus IBI305[hazard ratio(HR):1.16;95%confidence interval(CI):0.80–1.68]and camrelizumab plus apatinib(HR:1.06;95%CI:0.75–1.51).The combination therapies,apart from atezolizumab plus cabozantinib in OS and durvalumab plus tremelimumab in PFS,had higher P-score than single-agent MTAs or *** survival benefits were associated with a high risk of adverse events leading to treatment *** proportion of patients with hepatitis B virus-related HCC receiving ICIs combinations might positively correlate with survival advantages(R2=0.8039,p=0.0155).Conclusion:This NMA demonstrated that atezolizumab plus bevacizumab remains the stand of care and confers comparable survival benefits to sintilimab plus IBI305 and camrelizumab plus apatinib in first-line therapy for *** optimal treatment algorithms should consider efficacy,safety,and etiology.

关键词： Hepatocellular carcinoma Systemic therapy Immunotherapy Molecular targeted therapy Tyrosine protein kinase inhibitors Overall survival

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Comparison of the veracity of real-time perfusion, harmonic angio, and ultraharmonic myocardial contrast imaging modes in evaluation of acute myocardial infarction area

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Chinese Medical Journal 2006年第3期119卷 179-184页

作者： XING Yan-qiu ZHANG Yun LI Da-qing LIU Xiang-qun LI Xiu-qin ZHAO Chang-qin CHEN Mei gao hai-qing Cardiology Unit of Senior Care Department Qilu HospitalShandong University Ji＇nan 250012 China

Background Innovative advancements in ultrasound instrumentation present a number of imaging modalities for myocardial contrast echocardiography （MCE） in ischemic syndromes. How well they compare to each other in diagnostic accuracy in the detection of acute myocardial infarction is unclear. The purpose of this study was to assess the relative accuracy of 3 different imaging modes of MCE, low mechanical index （MI） real-time perfusion imaging （RTPI）, triggered harmonic angio mode （HA）, and ultraharmonic imaging mode （UH） in the detection of acute experimental myocardial infarction within the time frame suitable for potential reperfusion. Methods MCE was performed in 10 open-chest dogs using RTPI, triggered HA and triggered UH modes at baseline and one hour after occlusion of left anterior descending coronary artery. Presence or absence of peffusion defects, and the perfusion defect size when present, were analyzed and compared with the infarct size delineated by triphenyltetrazolium chloride （TTC） staining. Results The infarct area was （15.8-2.4）% by TTC staining; Peffusion defect area by MCE was similar to anatomic infarct area in all the three MCE approaches：（16.1-2.7）% by RTPI mode, （15.5-2.9）% by HA mode, and （15.5-3.0）% by UH mode. The sensitivity, specificity and overall diagnostic accuracy in the detection of myocardial infarction were 100%, 88%, and 94% for RTPI mode, 88%, 100%, and 94 % for HA mode, and 100%, 75%, and 88% for UH mode. Conclusion All modes of MCE, RTPI, triggered HA mode and triggered UH mode have excellent diagnostic accuracy in the immediate hour of acute coronary occlusion within the optimal time frame suitable for reperfusion therapy.

关键词： myocardial contrast echocardiography myocardial infarction ultraharmonic imaging harmonic angio imaging real-time perfusion imaging

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Cubic S/N co-doped TiO_(2) with rich oxygen vacancies from Ti-MOFs for efficient elimination of formaldehyde

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Chinese Chemical Letters 2024年第2期35卷 512-515页

作者： qing gao Lei Sun Zhihua Wang Jiguang Deng State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China Beijing Key Laboratory for Green Catalysis and Separation Key Laboratory of Beijing on Regional Air Pollution ControlKey Laboratory of Advanced Functional MaterialsEducation Ministry of ChinaDepartment of Chemical EngineeringBeijing University of TechnologyBeijing 100124China

The cubic S/N co-doped TiO_(2)(TNSx,x is the calcination temperature)photocatalysts with rich oxygen vacancies were obtained by high temperature calcination of sulfur powder and titanium-based MOFs NH_(2)-MIL-125 for the photocatalytic removal of gaseous formaldehyde(a volatile organic compound).Among the obtained catalysts,the presence of oxygen vacancies restricted photogenerated electron and holes recombination.98.00%removal of gaseous formaldehyde in 150 min could be achieved over TNS600 by xenon *** removal efficiency for formaldehyde was well retained for five cycle *** results from PL,TRPL and EIS revealed that TNS600 had the best separation efficiency of photogenerated electrons and holes,and the enhanced charge separation led to a significant increase in photocatalytic *** photocatalytic oxidation mechanism indicated that the ^(•)OH and ^(•)O_(2)−radicals were mainly involved in the efficient elimination of gaseous formaldehyde and were able to mineralize formaldehyde to H_(2)O and CO_(2).

关键词： Metal-organic frameworks Photocatalysis Formaldehyde removal S/N co-doped TiO_(2) Oxygen vacancies

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Natural Anti-oxidants——Trace Elements

Natural Anti-oxidants——Trace Elements

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首届泰山微量元素高级论坛

作者： gao hai-qing Qi-lu Hospital of Shandong University

＜正＞Contents Introduction Oxidative Stress and Diseases Trace Elements and Oxidative Stress Trace Elements Supplement Introduction Oxidative Stress

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