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Nitrogen-containing linkage-bonds in covalent organic frameworks:Synthesis and applications
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作者 liying Ou Zhenluan Xue +5 位作者 bo li Zhiwei Jin Jiaochan Zhong lixia Yang Penghui Shao Shenglian Luo 《Chinese Chemical Letters》 2025年第6期119-129,共11页
Covalent organic frameworks(COFs)are crystalline porous polymeric materials composed of organic monomers connected by strong covalent bonds and offer high stability,good crystallinity,a large specific surface area,and... Covalent organic frameworks(COFs)are crystalline porous polymeric materials composed of organic monomers connected by strong covalent bonds and offer high stability,good crystallinity,a large specific surface area,and controllable structures.COFs are widely used in the fields of adsorption and separation,catalysis,photovoltaics,and drug-delivery.The structural regulation and performance optimization of COFs can be realized through the modification of ligands and the selection of linkage methods.In which,the types of linkage are closely related to the stability and performance of COFs.In this review,nitrogencontaining linkage-bonds(NCLBs)in COFs are divided into N-containing double bonds,N-containing conjugated rings and N-containing unconjugated rings.The association between structure and performance of COFs is elaborated and the synthesis methods of COFs are systematically summarized.Moreover,the structural design,theoretical prediction and machinable application of COFs are prospected. 展开更多
关键词 Covalent organic frameworks Nitrogen-containing linkage-bonds Structure and properties Synthesis strategy and application Porous materials
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Ep,gallocatechin-3-gallate ameliorates erectile function in aged rats via regulation of PRMT1/ DDAH/ADMA/NOS metabolism pathway 被引量:9
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作者 Dong Chen Ke-Qin Zhang +3 位作者 bo li Ding-Qi Sun Hui Zhang Qiang Fu 《Asian Journal of Andrology》 SCIE CAS CSCD 2017年第3期291-297,共7页
Aging-related ED is predominantly attributed to neurovascular dysfunction mediated by NO suppression and increased oxidative stress in penis. The alterations of protein arginine methyltransferases 1 (PRMT1)/dimethyl... Aging-related ED is predominantly attributed to neurovascular dysfunction mediated by NO suppression and increased oxidative stress in penis. The alterations of protein arginine methyltransferases 1 (PRMT1)/dimethylarginine dimethylaminohydrolase (DDAH)/ asymmetrical dimethylarginine (ADMA)/NO synthase (NOS) pathway regulate NO production in the vascular endothelium. Epigallocatechin-3-gallate (EGCG) is one of the most abundant and antioxidative ingredients isolated from green tea. In the present study, 40 Sprague-Dawley rats were randomly distributed into four groups: one young rat group and three aged rat groups treated with daily gavage feedings of EGCG at doses of O, 10 mg kg-1, and 100 mg kg-1 for 12 weeks, respectively. Erectile function was assessed by electrical stimulation of the cavernous nerves with intracavernous pressure (ICP) measurement. After euthanasia, penile tissue was investigated using Western blot and ELISA to assess the PRMTI/DDAH/ADMA/NOS metabolism pathway. Superoxide dismutase (SOD) and malondialdehyde (MDA) levels were detected by colorimetry. We also evaluated smooth muscle contents. The ratio of maximal ICP and mean systemic arterial pressure (MAP) was markedly higher in EGCG-treated aged rats than in untreated aged rats. We found that DDAH 1 and DDAH2 were expressed in cavernosal tissue, and they were downregulated in corpora of aged rats. The administration of EGCG upregulated the expression and activity of DDAH. In contrast, EGCG treatment downregulated the expression of PRMT1 and ADMA content. Moreover, EGCG-treated rats showed an improvement in smooth muscle expression, the ratio of smooth muscle cell/collagen fibril, SOD activity, and MDA levels when compared with untreated aged rats. 展开更多
关键词 asymmetrical dimethylarginine dimethylarginine dimethylaminohydrolase epigallocatechin-3-gallate erectile dysfunction oxidative stress protein arginine methyltransferases 1
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A New Flexible Multibody Dynamics Analysis Methodology of Deployable Structures with Scissor-Like Elements 被引量:6
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作者 Qi’an Peng Sanmin Wang +1 位作者 Changjian Zhi bo li 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2019年第5期107-116,共10页
There are vast constraint equations in conventional dynamics analysis of deployable structures,which lead to differential-algebraic equations(DAEs)solved hard.To reduce the difficulty of solving and the amount of equa... There are vast constraint equations in conventional dynamics analysis of deployable structures,which lead to differential-algebraic equations(DAEs)solved hard.To reduce the difficulty of solving and the amount of equations,a new flexible multibody dynamics analysis methodology of deployable structures with scissor-like elements(SLEs)is presented.Firstly,a precise model of a flexible bar of SLE is established by the higher order shear deformable beam element based on the absolute nodal coordinate formulation(ANCF),and the master/slave freedom method is used to obtain the dynamics equations of SLEs without constraint equations.Secondly,according to features of deployable structures,the specification matrix method(SMM)is proposed to eliminate the constraint equations among SLEs in the frame of ANCF.With this method,the inner and the boundary nodal coordinates of element characteristic matrices can be separated simply and efficiently,especially on condition that there are vast nodal coordinates.So the element characteristic matrices can be added end to end circularly.Thus,the dynamic model of deployable structure reduces dimension and can be assembled without any constraint equation.Next,a new iteration procedure for the generalized-a algorithm is presented to solve the ordinary differential equations(ODEs)of deployable structure.Finally,the proposed methodology is used to analyze the flexible multi-body dynamics of a planar linear array deployable structure based on three scissor-like elements.The simulation results show that flexibility has a significant influence on the deployment motion of the deployable structure.The proposed methodology indeed reduce the difficulty of solving and the amount of equations by eliminating redundant degrees of freedom and the constraint equations in scissor-like elements and among scissor-like elements. 展开更多
关键词 Flexible MULTIBODY dynamics Scissor-like elements ABSOLUTE NODAL COORDINATE FORMULATION Specification matrix method Ordinary differential EQUATIONS
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Genome-wide association analysis identified molecular markers associated with important tea flavor-related metabolites 被引量:17
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作者 Kaixing Fang Zhiqiang Xia +7 位作者 Hongjian li Xiaohui Jiang Dandan Qin Qiushuang Wang Qing Wang Chendong Pan bo li Hualing Wu 《Horticulture Research》 SCIE 2021年第1期714-730,共17页
The characteristic secondary metabolites in tea(theanine,caffeine,and catechins)are important factors contributing to unique tea flavors.However,there has been relatively little research on molecular markers related t... The characteristic secondary metabolites in tea(theanine,caffeine,and catechins)are important factors contributing to unique tea flavors.However,there has been relatively little research on molecular markers related to these metabolites.Thus,we conducted a genome-wide association analysis of the levels of these tea flavor-related metabolites in three seasons.The theanine,caffeine,and catechin levels in Population 1 comprising 191 tea plant germplasms were examined,which revealed that their heritability exceeded 0.5 in the analyzed seasons,with the following rank order(highest to lowest heritabilities):(+)-catechin>(−)-gallocatechin gallate>caffeine=(−)-epicatechin>(−)-epigallocatechin-3-gallate>theanine>(−)-epigallocatechin>(−)-epicatechin-3-gallate>catechin gallate>(+)-gallocatechin.The SNPs detected by amplified-fragment SNP and methylation sequencing divided Population 1 into three groups and seven subgroups.An association analysis yielded 307 SNP markers related to theanine,caffeine,and catechins that were common to all three seasons.Some of the markers were pleiotropic.The functional annotation of 180 key genes at the SNP loci revealed that FLS,UGT,MYB,and WD40 domain-containing proteins,as well as ATP-binding cassette transporters,may be important for catechin synthesis.KEGG and GO analyses indicated that these genes are associated with metabolic pathways and secondary metabolite biosynthesis.Moreover,in Population 2(98 tea plant germplasm resources),30 candidate SNPs were verified,including 17 SNPs that were significantly or extremely significantly associated with specific metabolite levels.These results will provide a foundation for future research on important flavor-related metabolites and may help accelerate the breeding of new tea varieties. 展开更多
关键词 analysis BREEDING Population
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The origin of the extraordinary stability of mercury catalysts on the carbon support: the synergy effects between oxygen groups and defects revealed from a combined experimental and DFT study 被引量:7
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作者 Jian li Jiangtao Fan +6 位作者 Sajjad Ali Guojun Lan Haodong Tang Wenfeng Han Huazhang liu bo li Ying li 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第2期141-146,共6页
Thermal stability of HgCl2 has a pivotal importance for the hydrochlorination reaction as the loss of mercuric compounds is toxic and detrimental to environment.Here we report a low-mercury catalyst which has durabili... Thermal stability of HgCl2 has a pivotal importance for the hydrochlorination reaction as the loss of mercuric compounds is toxic and detrimental to environment.Here we report a low-mercury catalyst which has durability over 10000 h for acetylene hydrochlorination under the industrial condition.The stability of the catalyst is carefully analyzed from a combined experimental and density functional theory study.The analysis shows that the extraordinary stability of mercury catalyst is resulted from the synergy effects between surface oxygen groups and defective edge sites.The binding energy of HgCl2 is increased to be higher than 130 kJ/mol when adsorption is at the edge site with a nearby oxygen group.Therefore,the present study revealed that the thermal stability problem of mercury-based catalyst can be solved by simply adjusting the surface chemistry of activated carbon.Furthermore,the reported catalyst has already been successfully applied in the commercialized production of vinyl chloride. 展开更多
关键词 Mercury catalysts Thermal stability DEFECTS Oxygen groups Acetylene hydrochlorination
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Safety of hepatitis B virus core antibody-positive grafts in liver transplantation: A single-center experience in China 被引量:6
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作者 Ming Lei Lu-Nan Yan +7 位作者 Jia-Yin Yang Tian-Fu Wen bo li Wen-Tao Wang Hong Wu Ming-Qing Xu Zhe-Yu Chen Yong-Gang Wei 《World Journal of Gastroenterology》 SCIE CAS 2018年第48期5525-5536,共12页
BACKGROUND Given the shortage of suitable liver grafts for liver transplantation, proper use of hepatitis B core antibody-positive livers might be a possible way to enlarge the donor pool and to save patients with end... BACKGROUND Given the shortage of suitable liver grafts for liver transplantation, proper use of hepatitis B core antibody-positive livers might be a possible way to enlarge the donor pool and to save patients with end-stage liver diseases. However, the safety of hepatitis B virus core antibody positive(HBcAb+) donors has been controversial. Initial studies were mainly conducted overseas with relatively small numbers of HBcAb+ liver recipients, and there are few relevant reports in the population of China's Mainland. We hypothesized that the safety of HBcAb+ liver grafts is not suboptimal.AIM To evaluate the safety of using hepatitis B virus(HBV) core antibody-positive donors for liver transplantation in Chinese patients.METHODS We conducted a retrospective study enrolling 1071 patients who underwent liver transplantation consecutively from 2005 to 2016 at West China Hospital Liver Transplantation Center. Given the imbalance in several baseline variables, propensity score matching was used, and the outcomes of all recipients were reviewed in this study.RESULTS In the whole population, 230 patients received HBcAb+ and 841 patients received HBcAb negative(HBcAb-) liver grafts. The 1-, 3-and 5-year survival rates in patients and grafts between the two groups were similar(patient survival: 85.8% vs 87.2%, 77.4% vs 81.1%, 72.4% vs 76.7%, log-rank test, P = 0.16; graft survival: 83.2% vs 83.6%, 73.8% vs 75.9%, 70.8% vs 74.4%, log-rank test, P = 0.19). After propensity score matching, 210 pairs of patients were generated. The corresponding 1-, 3-and 5-year patient and graft survival rates showed no significant differences. Further studies illustrated that the post-transplant major complication rates and liver function recovery after surgery were also similar. In addition, multivariate regression analysis in the original cohort and propensity score-matched Cox analysis demonstrated that receiving HBcA b+ liver grafts was not a significant risk factor for long-term survival. These findings were consistent in both HBV surface antigen-positive(HBsAg+) and HBsA g negative(HBsAg-) patients.Newly diagnosed HBV infection had a relatively higher incidence in HBsAg-patients with HBcAb+ liver grafts(13.23%), in which HBV naive recipients suffered most(31.82%), although this difference did not affect patient and graft survival(P = 0.50 and P = 0.49, respectively). Recipients with a high HBV surface antibody(anti-HBs) titer(more than 100 IU/L) before transplantation and antiviral prophylaxis with nucleos(t)ide antiviral agents post-operation, such as nucleos(t)ide antiviral agents, had lower de novo HBV infection risks. CONCLUSION HBcA b+ liver grafts do not affect the long-term outcome of the recipients. Combined with proper postoperative antiviral prophylaxis, utilization of HBcAb+ grafts is rational and feasible. 展开更多
关键词 Liver TRANSPLANTATION Long-term OUTCOME HEPATITIS B core ANTIBODY HEPATITIS B virus infection
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Treatment of the acute thromboembolic event during endovascular embolization of intracranial aneurysm 被引量:14
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作者 Bing Zhou Yang He +5 位作者 Jun Cheng XiaoDong Lu MingZhao Zhang bo li RongQing Qin ZhongMing Gao 《Journal of Interventional Medicine》 2020年第4期208-212,共5页
Objective:The study aimed to discuss the treatment of acute thromboembolic event(TE)during endovascular embolization of intracranial aneurysms.Methods:Between April 2013 and April 2019,158 patients with 167 intracrani... Objective:The study aimed to discuss the treatment of acute thromboembolic event(TE)during endovascular embolization of intracranial aneurysms.Methods:Between April 2013 and April 2019,158 patients with 167 intracranial aneurysms were treated with endovascular embolization in our hospital,in which 9 cases of acute TEs occurred during the embolization procedures.The clinical data,radiological findings and treatments of the 9 patients were reviewed and analyzed.Results:The TEs occurred at the aneurysmal neck in 3 patients,at distal part of the parent artery in 3,in the stent in 2,and at the proximal part of the parent artery in 1.Intra-arterial(IA)infusion of tirofiban were performed in 6 patients,mechanical thromboectomy(MT)with a stent in 2 patients,and combined use of the two methods in 1 patients.According to the modified Thrombolysis In Cerebral Infarction(mTICI)score,7 patients had recanalization of 2b/3a,1 patients had recanalization of 1,and 1 patients had recanalization of 0.At discharge,the mRS score was 0 in 3 patients,1 in 3 patients,and 2,3,4 in 1 patient each.6 months after the endovascular treatment,the mRS score was 0 in 5 patients,1 in 2 patients,and 3 in 1 patient.Conclusions:IA tirofiban and MT are effective remedies for the acute TE during endovascular embolization of intracranial aneurysm,reasonable selection of which may improve the prognosis of patients. 展开更多
关键词 ANEURYSM EMBOLIZATION Mechanical thromboectomy MT Thromboembolic event TE Intra-arterial IA
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Influence of the Substrate Orientation on the Isothermal Solidification during TLP Bonding Single Crystal Superalloys 被引量:4
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作者 Naicheng Sheng bo li +3 位作者 Jide liu Tao Jin Xiaofeng Sun Zhuangqi Hu 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2014年第3期213-216,共4页
Angle deviations between the two substrates during transient liquid phase (TLP) bonding single crystal superalloys cannot be avoided. In the present work, specimens have been prepared to investigate the influences o... Angle deviations between the two substrates during transient liquid phase (TLP) bonding single crystal superalloys cannot be avoided. In the present work, specimens have been prepared to investigate the influences of the various substrate orientations. It is found that the width of the non-isothermal solidification zone (NSZ) is linear with the square root of the isothermal solidification time. This suggests that the isothermal solidification process is B-diffusion controlled in different substrate orientation deviations. And also the width of the NSZ increases with increasing angle deviation, indicating that the isothermal solidification time needed in the TLP bonding increases with increasing orientation deviation between the two substrates. 展开更多
关键词 Transient liquid phase (TLP) bonding Single crystal superalloys Orientation deviation Bonding time
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Mechanism underlying carbon tetrachloride-inhibited protein synthesis in liver 被引量:4
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作者 Xiao-Wen li Rong Zhu +5 位作者 bo li Mei Zhou Qing-Jian Sheng Ye-Peng Yang Nan-Yin Han Zai-Quan li 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第31期3950-3956,共7页
AIM: To study the mechanism underlying carbon tetrachloride (CCl4)-induced alterations of protein synthesis in liver. METHODS: Male Sprague-Dawley rats were given CCl4 (1 mL/100 g body weight) and 3H-leucine incorpora... AIM: To study the mechanism underlying carbon tetrachloride (CCl4)-induced alterations of protein synthesis in liver. METHODS: Male Sprague-Dawley rats were given CCl4 (1 mL/100 g body weight) and 3H-leucine incorporation. Malondialdehyde (MDA) level in the liver, in vitro response of hepatocyte nuclei nucleotide triphosphatase (NTPase) to free radicals, and nuclear export of total mRNA with 3'-poly A+ were measured respectively. Survival response of HepG2 cells to CCl4 treatment was assessed by methyl thiazolyl tetrazolium. Km and Vmax values of nuclear envelope NTPase activity in liver of rats treated with CCl4 were assayed by a double-reciprocal plot. RESULTS: The protein synthesis was inhibited while the MDA level was signif icantly increased in liver of rats treated with CCl4. In addition, CCl4 decreased the NTPase binding capacity of nuclear envelope (Km value) in cultured HepG2 cells. Moreover, in vitro ferrous radicals from Fenton's system suppressed the NTPase activity of liver nuclear envelope in a dose-dependent manner. Down-regulation of the nuclear envelope NTPase activity indicated a lower energy provision for nucleocytoplasmic transport of mRNA molecules, an evidence in CCl4-treated HepG2 cells correspondingly supported by the nuclear sequestration of poly (A)+ mRNA molecules in morphological hybridization research. CONCLUSION: Inhibition of mRNA transport, suggestive of decreased NTPase activity of the nuclear envelope, may be involved in carbon tetrachloride-inhibited protein synthesis in liver. 展开更多
关键词 Carbon tetrachloride Nuclear envelope nucleotide triphosphatase Nucleocytoplasmic transport inhibition Hydroxyl radical
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Cost-effectiveness analysis of transcatheter arterial chemoembolization with or without sorafenib for the treatment of unresectable hepatocellular carcinoma 被引量:4
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作者 Rong-Ce Zhao Jing Zhou +4 位作者 Yong-Gang Wei Fei liu Ke-Fei Chen Qiu li bo li 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2017年第5期493-498,共6页
BACKGROUND: Transcatheter arterial chemoembolization(TACE) and TACE in combination with sorafenib(TACEsorafenib) have shown a significant survival benefit for the treatment of unresectable hepatocellular carcinoma(HCC... BACKGROUND: Transcatheter arterial chemoembolization(TACE) and TACE in combination with sorafenib(TACEsorafenib) have shown a significant survival benefit for the treatment of unresectable hepatocellular carcinoma(HCC). Adopting either as a first-line therapy carries major cost and resource implications. The objective of this study was to estimate the relative cost-effectiveness of TACE against TACE-sorafenib for unresectable HCC using a decision analytic model.METHODS: A Markov cohort model was developed to compare TACE and TACE-sorafenib. Transition probabilities and utilities were obtained from systematic literature reviews, and costs were obtained from West China Hospital, Sichuan University, China. Survival benefits were reported in quality-adjusted life-years(QALYs). The incremental cost-effectiveness ratio(ICER) was calculated. Sensitive analysis was performed by varying potentially modifiable parameters of the model.RESULTS: The base-case analysis showed that TACE cost $26 951 and yielded survival of 0.71 QALYs, and TACE-sorafenib cost $44 542 and yielded survival of 1.02 QALYs in the entire treatment. The ICER of TACE-sorafenib versus TACE was $56 745 per QALY gained, which was above threshold for cost-effectiveness in China. Sensitivity analysis revealed that the major driver of ICER was the cost post TACE-sorafenib therapy with stable state.CONCLUSION: TACE is a more cost-effective strategy than TACE-sorafenib for the treatment of unresectable HCC. 展开更多
关键词 hepatocellular carcinoma transcatheter arterial chemoembolization TACE in combination with sorafenib COST-EFFECTIVENESS
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Hierarchical Self-assembly of Well-Defined Louver-Like P-Doped Carbon Nitride Nanowire Arrays with Highly Effcient Hydrogen Evolution 被引量:3
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作者 bo li Yuan Si +6 位作者 Qian Fang Ying Shi Wei‑Qing Huang Wangyu Hu Anlian Pan Xiaoxing Fan Gui‑Fang Huang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2020年第4期76-91,共16页
Self-assembled nanostructure arrays integrating the advantages of the intrinsic characters of nanostructure as well as the array stability are appealing in advanced materials.However,the precise bottom-up synthesis of... Self-assembled nanostructure arrays integrating the advantages of the intrinsic characters of nanostructure as well as the array stability are appealing in advanced materials.However,the precise bottom-up synthesis of nanostructure arrays without templates or substrates is quite challenging because of the general occurrence of homogeneous nucleation and the difficult manipulation of noncovalent interactions.Herein,we first report the precisely manipulated synthesis of well-defined louver-like P-doped carbon nitride nanowire arrays(L-PCN)via a supramolecular self-assembly method by regulating the noncovalent interactions through hydrogen bond.With this strategy,CN nanowires align in the outer frame with the separation and spatial location achieving ultrastability and outstanding photoelectricity properties.Significantly,this self-assembly L-PCN exhibits a superior visible light-driven hydrogen evolution activity of 1872.9μmol h^−1 g^−1,rendering a^25.6-fold enhancement compared to bulk CN,and high photostability.Moreover,an apparent quantum efficiency of 6.93%is achieved for hydrogen evolution at 420±15 nm.The experimental results and first-principles calculations demonstrate that the remarkable enhancement of photocatalytic activity of L-PCN can be attributed to the synergetic effect of structural topology and dopant.These findings suggest that we are able to design particular hierarchical nanostructures with desirable performance using hydrogen-bond engineering. 展开更多
关键词 SELF-ASSEMBLY Carbon nitride P-doped Nanowire arrays Hydrogen evolution
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A cloud optical and microphysical property product for the advanced geosynchronous radiation imager onboard China's Fengyun-4 satellites: The first version 被引量:2
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作者 Chao liu Yuxing Song +5 位作者 Ganning Zhou Shiwen Teng bo li Na Xu Feng Lu Peng Zhang 《Atmospheric and Oceanic Science Letters》 CSCD 2023年第3期52-57,共6页
风云四号作为中国新一代静止气象卫星,提供了高时空分辨率的监测产品。本文介绍风云四号搭载的先进地球同步轨道辐射成像仪AGRI的云光学和微物理特性产品.该产品包含了基于双光谱通道反演的云光学厚度和云粒子有效半径产品,以及基于机... 风云四号作为中国新一代静止气象卫星,提供了高时空分辨率的监测产品。本文介绍风云四号搭载的先进地球同步轨道辐射成像仪AGRI的云光学和微物理特性产品.该产品包含了基于双光谱通道反演的云光学厚度和云粒子有效半径产品,以及基于机器学习的云识别和云相态产品。与时空匹配的主动卫星观测结果对比显示,该产品的云识别和云相态的准确率分别在95%和85%;该产品提供的云光学厚度和云有效粒径与经典的MODIS产品的相关系数达到0.76和0.63.团队将持续优化和更新该云光学和微物理特性定量产品,服务风云四号卫星定量应用。 展开更多
关键词 风云四号 先进地球同步轨道辐射成像仪 云相态 云光学厚度 云有效粒子半径
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Transient liquid-phase bonding of superalloy K465 using a Ni-Cr-Fe-B-Si amorphous interlayer alloy 被引量:2
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作者 Ji-De liu bo li +3 位作者 Yuan Sun Tao Jin Xiao-Feng Sun Zhuang-Qi Hu 《Rare Metals》 SCIE EI CAS CSCD 2020年第4期408-412,共5页
A kind of Ni-Cr-Fe-B-Si system amorphous alloy was used as interlayer in transient liquid-phase bonding(TLP bonding)of polycrystalline superalloy K465.The bonding behavior,microstructure feature and the tensile proper... A kind of Ni-Cr-Fe-B-Si system amorphous alloy was used as interlayer in transient liquid-phase bonding(TLP bonding)of polycrystalline superalloy K465.The bonding behavior,microstructure feature and the tensile properties of the joints were investigated.There are B-rich phase and Si-rich phase formed in the center of the seam after bonding at 1210℃for 30 min.The isothermal solidification is complete after bonding at 1210℃for 4 h.The relationship of the average width of the remnant eutectic zone and bonding time at 1210℃is nonlinear.The tensile strength of the bonded joint at room temperature and 900℃is comparable to that of K465 alloy. 展开更多
关键词 Interlayer alloy Transient liquid-phase bonding SUPERALLOY K465 Alloy
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Expression of p53, p21^(CIP1/WAF1) and eIF4E in the adjacent tissues of oral squamous cell carcinoma:establishing the molecular boundary and a cancer progression model 被引量:1
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作者 Yi li bo li +4 位作者 bo Xu bo Han Hui Xia Qian-Ming Chen Long-Jiang li 《International Journal of Oral Science》 SCIE CAS CSCD 2015年第3期161-168,共8页
The present study evaluated the expression of key molecules and the status of DNA in both oral squamous cell carcinoma(OSCC) and adjacent tissues to establish a molecular surgical boundary and provide a cancer progr... The present study evaluated the expression of key molecules and the status of DNA in both oral squamous cell carcinoma(OSCC) and adjacent tissues to establish a molecular surgical boundary and provide a cancer progression model. Biopsy samples from 50 OSCC patients were divided into T(cancer), P1(0–0.5 cm), P2(0.5–1 cm), P3(1–1.5 cm) and P4(1.5–2 cm) groups based on the distances from the visible boundary of the primary focus. Twenty samples of normal mucosa were used as controls. We used immunohistochemical staining and flow cytometry to evaluate p53, p21CIP1/WAF1, e IF4 E and Ki-67 expression and to determine DNA status, respectively. Sub-mucosal invasion was present in the P1 and P2 groups as determined by haematoxylin and eosin staining.Mutant p53 expression decreased gradually from cancerous to normal mucosae, whereas p21CIP1/WAF1 expression displayed an opposite trend. e IF4 E expression decreased from cancerous to normal mucosae. Ki-67 expression, the heteroploidy ratio, S-phase fraction and proliferative index decreased gradually with the distance from the tumour centre. Based on these results, we suggest that the resection boundary in OSCC surgery should be beyond 2 cm from the tumour. Additionally, the adjacent tissues of the primary focus could be used as a model for assessing cancer progression. 展开更多
关键词 e IF4E molecular boundary oral squamous cell carcinoma P21 P53
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A novel method of suppressing machining vibration in robotic milling using magneto-rheological foam damper 被引量:1
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作者 bo li Chenxin SU +3 位作者 Wei ZHAO Shengli SONG Wei TIAN Wenhe liAO 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2024年第12期522-543,共22页
Owing to their remarkable flexibility and favorable cost-effectiveness,industrial robots have found extensive applications to cutting of materials across sophisticated manufacturing fields.However,the structurally low... Owing to their remarkable flexibility and favorable cost-effectiveness,industrial robots have found extensive applications to cutting of materials across sophisticated manufacturing fields.However,the structurally low rigidity of these robots renders the tool tip prone to substantial oscillations during machining processes,significantly impacting product fabrication quality.The objective of this study is to present a novel methodology employing magnetorheological dampers for mitigating vibrations during robotic milling operations.Specifically,a new type of ring nested Magneto-Rheological Foam Damper(MRFD)working in the squeeze mode is developed.Firstly,the MRFD’s structure is designed considering the vibrational characteristics of robotic milling.Subsequently,a damping force model of the MRFD is derived.The feasibility of the MRFD’s structural design is validated by the finite element analyses,which is instrumental in comprehending the influence of structural parameters on the electromagnetic characteristics of the MRFD.Next,a prototype of the MRFD is fabricated selecting appropriate parameters.Finally,a series of excitation and milling experiments are conducted on a KUKA KR500 robot.The outcomes demonstrate a substantial reduction(37%-69%)in radial vibration amplitude at the tool tip during robotic milling,highlighting the effectiveness of the developed MRFD.This research endeavor has introduced a pioneering avenue and framework for vibration control in robotic milling,offering a novel paradigm for enhancing the precision of robotic machining. 展开更多
关键词 Industrial robots Machining vibration Magneto-rheological dampers Robotic milling Vibration suppression
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Efficacy and Safety of Lianhua Qingke Tablets in the Treatment of Long Coronavirus Disease (COVID) Cough: A Randomized, Double-Blind, Placebo-Controlled, Multicenter Clinical Study 被引量:1
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作者 Xiaolong Xu Jie Ying +12 位作者 Taiping Tian Tengwen liu Chunhua Chi Zhizhong Gong Jingpeng Gao Meiping Qian Wei Tan Ran Cao Shuixian Lv Zhougui ling Shuo Wang bo li Qingquan liu 《Engineering》 SCIE EI CAS CSCD 2024年第9期61-69,共9页
Lianhua Qingke tablets,a patented traditional Chinese medicine that has validated clinical efficacy for treating cough caused by severe acute respiratory syndrome coronavirus 2 infection,lack rigorous evidence-based r... Lianhua Qingke tablets,a patented traditional Chinese medicine that has validated clinical efficacy for treating cough caused by severe acute respiratory syndrome coronavirus 2 infection,lack rigorous evidence-based research evaluating their effect on long coronavirus disease(COVID)cough.A randomized,double-blind,placebo-controlled,multicenter clinical study was conducted among patients with long COVID cough from 19 hospitals and 23 community health centers in China.Patients were randomized 1:1 to receive either Lianhua Qingke tablets or placebo orally for 14 days(four tablets,1.84 g,three times a day).The primary endpoint indicator was the disappearance of cough,with the remission of cough also considered.Among 482 randomized patients,480(full analysis set 480;per-protocol set 470;safety set 480)were included in the primary analysis.According to the full analysis,the time until cough disappearance was significantly shorter in the trial group than in the control group,with a significant increase in the 14-day cough disappearance rate.Accordingly,the time to cough remission was significantly shorter in the trial group than in the control group.The change in the total symptom score was significantly greater in the trial group than in the control group on days 7 and 14,consistent with the results indicated by the visual analog scale(VAS)and cough evaluation test(CET)scores.No serious adverse events were recorded during the study.Lianhua Qingke tablets significantly improved the clinical symptoms of patients with long COVID cough. 展开更多
关键词 Long coronavirus disease(COVID)cough Traditional Chinese medicine Clinical trial Efficacy Safety
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Transcriptome and metabolome analysis reveal that oral secretions from Helicoverpa armigera and Spodoptera litura influence wound-induced host response in cotton 被引量:1
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作者 Huan Si Hongling liu +9 位作者 Yiwen Sun Zhongping Xu Sijia liang bo li Xiao Ding Jianying li Qiongqiong Wang lin Sun Xianlong Zhang Shuangxia Jin 《The Crop Journal》 SCIE CSCD 2020年第6期929-942,共14页
Cotton(Gossypium hirsutum)is an important fiber crop worldwide.Insect attack causes cotton yield and quality losses.However,little is known about the mechanism of cotton response to insect attack.We simulated insect f... Cotton(Gossypium hirsutum)is an important fiber crop worldwide.Insect attack causes cotton yield and quality losses.However,little is known about the mechanism of cotton response to insect attack.We simulated insect feeding by applying insect oral secretions(OS)to wounds,and combined transcriptome and metabolome analysis to investigate how OS from two major pest species(Helicoverpa armigera and Spodoptera litura)affect cotton defense responses.We found that respectively 12,668 and 13,379 genes were differentially expressed in comparison with wounding alone.On addition of OS,the jasmonic acid signaling pathway was rapidly and strongly induced,whereas genes involved in salicylic acid biosynthesis were downregulated.On constructing a coexpression gene network,we identified a hub gene encoding a leucine-rich repeat receptor kinase that may play an important role in early signal recognition and transduction.OS from the two insect species altered the abundance of flavonoid-related compounds in different patterns.Gossypol remained in lower concentration after OS application than after wounding alone,suggesting a suppressive effect of OS on cotton defense response.This study illustrated transcriptional and metabolic changes of cotton in responding to OS from two chewing insect species,identified potential key response genes,and revealed evidence for OS inhibition of wounding-induced cotton defense response. 展开更多
关键词 Oral secretions Helicoverpa armigera Spodoptera litura COTTON Host plant defense
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Knockdown of PGC1α suppresses dysplastic oral keratinocytes proliferation through reprogramming energy metabolism 被引量:1
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作者 Yunkun liu Nengwen Huang +6 位作者 Xianghe Qiao Zhiyu Gu Yongzhi Wu Jinjin li Chengzhou Wu bo li Longjiang li 《International Journal of Oral Science》 SCIE CAS CSCD 2023年第3期502-512,共11页
Oral potentially malignant disorders(OPMDs)are precursors of oral squamous cell carcinoma(OSCC).Deregulated cellular energy metabolism is a critical hallmark of cancer cells.Peroxisome proliferator-activated receptor-... Oral potentially malignant disorders(OPMDs)are precursors of oral squamous cell carcinoma(OSCC).Deregulated cellular energy metabolism is a critical hallmark of cancer cells.Peroxisome proliferator-activated receptor-gamma coactivator-1 alpha(PGC1α)plays vital role in mitochondrial energy metabolism.However,the molecular mechanism of PGC1αon OPMDs progression is less unclear.Therefore,we investigated the effects of knockdown PGC1αon human dysplastic oral keratinocytes(DOKs)comprehensively,including cell proliferation,cell cycle,apoptosis,xenograft tumor,mitochondrial DNA(mtDNA),mitochondrial electron transport chain complexes(ETC),reactive oxygen species(ROS),oxygen consumption rate(OCR),extracellular acidification rate(ECAR),and glucose uptake.We found that knockdown PGC1αsignificantly inhibited the proliferation of DOKs in vitro and tumor growth in vivo,induced S-phase arrest,and suppressed PI3K/Akt signaling pathway without affecting cell apoptosis.Mechanistically,downregulated of PGC1αdecreased mtDNA,ETC,and OCR,while enhancing ROS,glucose uptake,ECAR,and glycolysis by regulating lactate dehydrogenase A(LDHA).Moreover,SR18292(an inhibitor of PGC1α)induced oxidative phosphorylation dysfunction of DOKs and declined DOK xenograft tumor progression.Thus,our work suggests that PGC1αplays a crucial role in cell proliferation by reprograming energy metabolism and interfering with energy metabolism,acting as a potential therapeutic target for OPMDs. 展开更多
关键词 metabolism energy OCR
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A simultaneous occurrence of pulmonary embolism and cerebral infarction following Micra^(TM)leadless pacemaker implantation 被引量:1
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作者 Song-Hua li Shao-Hua DONG +5 位作者 Tong KAN Sun YUE bo li Yang LU Pan li Zhi-Fu GUO 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2023年第10期756-759,共4页
Since the successful implantation of the first cardiac pacemaker(PM)in 1958,PM has been widely used in clinical practice.With the advancement of interventional technology,PMs have become smaller and more effective.Des... Since the successful implantation of the first cardiac pacemaker(PM)in 1958,PM has been widely used in clinical practice.With the advancement of interventional technology,PMs have become smaller and more effective.Despite continuous improvements,traditional PMs remain associated with a proportional risk of immediate-and short-term complications(9%–12%),[1]which are mainly related to electrodes or pockets.Short-term complications include pneumothorax,cardiac tamponade. 展开更多
关键词 CARDIAC IMPLANTATION CEREBRAL
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