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The relationship among amyloid-βdeposition,sphingomyelin level,and the expression and function of P-glycoprotein in Alzheimer’s disease pathological process 被引量:1
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作者 Zi-Kang Xing Li-Sha Du +6 位作者 Xin Fang Heng Liang Sheng-Nan Zhang lei shi Chun-Xiang Kuang Tian-Xiong Han Qing Yang 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第6期1300-1307,共8页
In Alzheimer’s disease,the transporter P-glycoprotein is responsible for the clearance of amyloid-βin the brain.Amyloid-βcorrelates with the sphingomyelin metabolism,and sphingomyelin participates in the regulation... In Alzheimer’s disease,the transporter P-glycoprotein is responsible for the clearance of amyloid-βin the brain.Amyloid-βcorrelates with the sphingomyelin metabolism,and sphingomyelin participates in the regulation of P-glycoprotein.The amyloid cascade hypothesis describes amyloid-βas the central cause of Alzheimer’s disease neuropathology.Better understanding of the change of P-glycoprotein and sphingomyelin along with amyloid-βand their potential association in the pathological process of Alzheimer’s disease is critical.Herein,we found that the expression of P-glycoprotein in APP/PS1 mice tended to increase with age and was significantly higher at 9 and 12 months of age than that in wild-type mice at comparable age.The functionality of P-glycoprotein of APP/PS1 mice did not change with age but was significantly lower than that of wild-type mice at 12 months of age.Decreased sphingomyelin levels,increased ceramide levels,and the increased expression and activity of neutral sphingomyelinase 1 were observed in APP/PS1 mice at 9 and 12 months of age compared with the levels in wild-type mice.Similar results were observed in the Alzheimer’s disease mouse model induced by intracerebroventricular injection of amyloid-β1-42 and human cerebral microvascular endothelial cells treated with amyloid-β1-42.In human cerebral microvascular endothelial cells,neutral sphingomyelinase 1 inhibitor interfered with the changes of sphingomyelin metabolism and P-glycoprotein expression and functionality caused by amyloid-β1-42 treatment.Neutral sphingomyelinase 1 regulated the expression and functionality of P-glycoprotein and the levels of sphingomyelin and ceramide.Together,these findings indicate that neutral sphingomyelinase 1 regulates the expression and function of P-glycoprotein via the sphingomyelin/ceramide pathway.These studies may serve as new pursuits for the development of anti-Alzheimer’s disease drugs. 展开更多
关键词 Alzheimer’s disease amyloid-β APP/PS1 mice CERAMIDE ezrin-radixin-moesin human cerebral microvascular endothelial cells neutral sphingomyelinase 1 P-GLYCOPROTEIN sphingomyelin synthase SPHINGOMYELIN
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超声振动对2195铝锂合金搅拌摩擦焊接头显微组织与力学性能的影响
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作者 戴翔 石磊 +2 位作者 田春燕 武传松 高嵩 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第1期80-93,共14页
采用新型超声振动强化搅拌摩擦焊对第三代2195-T6铝锂合金进行焊接,研究超声振动对接头显微组织与力学性能的影响。研究表明,超声振动强化搅拌摩擦焊能够增强塑性材料流动,进而抑制焊接缺陷,提高无缺陷接头的临界焊接速度。在保证接头... 采用新型超声振动强化搅拌摩擦焊对第三代2195-T6铝锂合金进行焊接,研究超声振动对接头显微组织与力学性能的影响。研究表明,超声振动强化搅拌摩擦焊能够增强塑性材料流动,进而抑制焊接缺陷,提高无缺陷接头的临界焊接速度。在保证接头抗拉强度达到母材75%的条件下,超声振动强化搅拌摩擦焊的焊接速度和效率均高于常规搅拌摩擦焊。施加超声振动能够大幅提升较高焊接速度条件下的接头力学性能。超声振动强化搅拌摩擦焊接头的极限抗拉强度为449.5 MPa,达到母材的83.1%。超声振动强化搅拌摩擦焊接能够在保证接头质量的前提下提升临界焊接速度和焊接效率。 展开更多
关键词 2195-T6铝锂合金 搅拌摩擦焊 超声振动强化搅拌摩擦焊 焊接速度 晶粒结构 接头性能
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Rosemary extract improves egg quality by altering gut barrier function,intestinal microbiota and oviductal gene expressions in late-phase laying hens
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作者 Lianhua Zhang Junwei Ge +7 位作者 Fei Gao Min Yang Hui Li Fei Xia Hongtong Bai Xiangshu Piao Zhiying Sun lei shi 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第1期295-312,共18页
Background Rosemary extract(RE)has been reported to exert antioxidant property.However,the application of RE in late-phase laying hens on egg quality,intestinal barrier and microbiota,and oviductal function has not be... Background Rosemary extract(RE)has been reported to exert antioxidant property.However,the application of RE in late-phase laying hens on egg quality,intestinal barrier and microbiota,and oviductal function has not been systematically studied.This study was investigated to detect the potential effects of RE on performance,egg quality,serum parameters,intestinal heath,cecal microbiota and metabolism,and oviductal gene expressions in late-phase laying hens.A total of 21065-week-old“Jing Tint 6”laying hens were randomly allocated into five treatments with six replicates and seven birds per replicate and fed basal diet(CON)or basal diet supplemented with chlortetracycline at 50 mg/kg(CTC)or RE at 50 mg/kg(RE50),100 mg/kg(RE100),and 200 mg/kg(RE200).Results Our results showed that RE200 improved(P<0.05)Haugh unit and n-6/n-3 of egg yolk,serum superoxide dismutase(SOD)compared with CON.No significant differences were observed for Haugh unit and n-6/n-3 of egg yolk among CTC,RE50,RE100 and RE200 groups.Compared with CTC and RE50 groups,RE200 increased serum SOD activity on d 28 and 56.Compared with CON,RE supplementation decreased(P<0.05)total cholesterol(TC)level.CTC,RE100 and RE200 decreased(P<0.05)serum interleukin-6(IL-6)content compared with CON.CTC and RE200 increased jejunal m RNA expression of ZO-1 and Occludin compared with CON.The biomarkers of cecal microbiota and metabolite induced by RE 200,including Firmicutes,Eisenbergiella,Paraprevotella,Papillibacter,and butyrate,were closely associated with Haugh unit,n-6/n-3,SOD,IL-6,and TC.PICRUSt2 analysis indicated that RE altered carbohydrate and amino acid metabolism of cecal microbiota and increased butyrate synthesizing enzymes,including 3-oxoacid Co A-transferase and butyrate-acetoacetate Co A-transferase.Moreover,transcriptomic analysis revealed that RE200 improved gene expressions and functional pathways related to immunity and albumen formation in the oviductal magnum.Conclusions Dietary supplementation with 200 mg/kg RE could increase egg quality of late-phase laying hens via modulating intestinal barrier,cecal microbiota and metabolism,and oviductal function.Overall,RE could be used as a promising feed additive to improve egg quality of laying hens at late stage of production. 展开更多
关键词 Intestinal health Laying hens MICROBIOTA Oviductal function PHYTOCHEMICALS Production
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Genome-wide and candidate gene association studies identify BnPAP17 as conferring the utilization of organic phosphorus in oilseed rape
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作者 Ping Xu Hao Li +6 位作者 Haiyuan Li Ge Zhao Shengjie Dai Xiaoyu Cui Zhenning Liu lei shi Xiaohua Wang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第4期1134-1149,共16页
Phosphorus(P)is essential for living plants,and P deficiency is one of the key factors limiting the yield in rapeseed production worldwide.As the most important organ for plants,root morphology traits(RMTs)play a key ... Phosphorus(P)is essential for living plants,and P deficiency is one of the key factors limiting the yield in rapeseed production worldwide.As the most important organ for plants,root morphology traits(RMTs)play a key role in P absorption.To investigate the genetic variability of RMT under low P availability,we dissected the genetic structure of RMTs by genome-wide association studies(GWAS),linkage mapping and candidate gene association studies(CGAS).A total of 52 suggestive loci were associated with RMTs under P stress conditions in 405 oilseed rape accessions.The purple acid phosphatase gene BnPAP17 was found to control the lateral root number(LRN)and root dry weight(RDW)under low P stress.The expression of BnPAP17 was increased in shoot tissue in P-efficient cultivars compared to root tissue and P-inefficient cultivars in response to low P stress.Moreover,the haplotype of BnPAP17^(Hap3)was detected for the selective breeding of P efficiency in oilseed rape.Over-expression of the BnPAP17^(Hap3)could promote the shoot and root growth with enhanced tolerance to low P stress and organic phosphorus(Po)utilization in oilseed rape.Collectively,these findings increase our understanding of the mechanisms underlying BnPAP17-mediated low P stress tolerance in oilseed rape. 展开更多
关键词 genome-wide association studies(GWAS) root morphology traits(RMTs) organic phosphorus(Po) oilseed rape BnPAP17
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Chord length sampling correction analysis for dispersion fuel in Monte Carlo simulation
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作者 Zhao-Yu Liang Ding She +1 位作者 Yu-Tong Wen lei shi 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第4期57-64,共8页
Dispersion fuels,knowned for their excellent safety performance,are widely used in advanced reactors,such as hightemperature gas-cooled reactors.Compared with deterministic methods,the Monte Carlo method has more adva... Dispersion fuels,knowned for their excellent safety performance,are widely used in advanced reactors,such as hightemperature gas-cooled reactors.Compared with deterministic methods,the Monte Carlo method has more advantages in the geometric modeling of stochastic media.The explicit modeling method has high computational accuracy and high computational cost.The chord length sampling(CLS)method can improve computational efficiency by sampling the chord length during neutron transport using the matrix chord length?s probability density function.This study shows that the excluded-volume effect in realistic stochastic media can introduce certain deviations into the CLS.A chord length correction approach is proposed to obtain the chord length correction factor by developing the Particle code based on equivalent transmission probability.Through numerical analysis against reference solutions from explicit modeling in the RMC code,it was demonstrated that CLS with the proposed correction method provides good accuracy for addressing the excludedvolume effect in realistic infinite stochastic media. 展开更多
关键词 Stochastic media Monte Carlo Chord length sampling Excluded-volume effect Chord length correction
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The influence of yttrium and manganese additions on the degradation and biocompatibility of magnesium-zinc-based alloys:In vitro and in vivo studies
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作者 lei shi Yang Yan +3 位作者 Chun-sheng Shao Kun Yu Bo Zhang Liang-jian Chen 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第2期608-624,共17页
The repair and regeneration of bone defects are highly challenging orthopedic problems.Recently,Mg-based implants have gained popularity due to their unique biodegradation and elastic modulus similar to that of human ... The repair and regeneration of bone defects are highly challenging orthopedic problems.Recently,Mg-based implants have gained popularity due to their unique biodegradation and elastic modulus similar to that of human bone.The aim of our study is to develop a magnesium alloy with a controllable degradation that can closely match bone tissue to help injuries heal in vivo and avoid cytotoxicity caused by a sudden increase in ion concentration.In this study,we prepared and modified Mg-3Zn,Mg-3Zn-1Y,and Mg-2Zn-1Mn by hot extrusion,and used Mg-2.5Y-2.5Nd was as a control.We then investigated the effect of additions of Y and Mn on alloys'properties.Our results show that Mn and Y can improve not only compression strength but also corrosion resistance.The alloy Mg-2Zn-1Mn demonstrated good cytocompatibility in vitro,and for this reason we selected it for implantation in vivo.The degraded Mg-2Zn-1Mn implanted a bone defect area did not cause obvious rejection and inflammatory reaction,and the degradation products left no signs of damage to the heart,liver,kidney,or brain.Furthermore,we find that Mg-2Zn-1Mn can promote an osteoinductive response in vivo and the formation of bone regeneration. 展开更多
关键词 Magnesium alloy BIODEGRADATION BIOCOMPATIBILITY Bone regeneration Bone defect repair
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OsMYB84,a transcriptional regulator of OsCOPT2 and OsHMA5,modulates copper uptake and transport and yield production in rice
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作者 Jingli Ding Chenchen Ji +6 位作者 Lu Yu Chuang Wang Guangda Ding Sheliang Wang lei shi Fangsen Xu Hongmei Cai 《The Crop Journal》 SCIE CSCD 2024年第2期456-469,共14页
Transcription factors regulating crop uptake and translocation of the micronutrient Cu have not been identified.We isolated a novel R2R3-MYB transcription factor,OsMYB84,and showed that it was a positive regulator inv... Transcription factors regulating crop uptake and translocation of the micronutrient Cu have not been identified.We isolated a novel R2R3-MYB transcription factor,OsMYB84,and showed that it was a positive regulator involved in uptake and transport of Cu via activation of OsCOPT2 and OsHMA expression.OsMYB84 was highly expressed in roots and anthers and induced by Cu.Overexpression of OsMYB84 promoted uptake and root-to-shoot translocation of Cu in rice,facilitated Cu distribution into grain and increased grain yield.In contrast,mutation of OsMYB84 reduced Cu concentration in xylem sap.OsMYB84 bound to the promoter region of OsCOPT2 and OsHMA5 and upregulated their expression.OsCOPT2 mutants showed reduced uptake of Cu and OsHMA5 overexpression lines showed increased root-to-shoot translocation of Cu. 展开更多
关键词 OsMYB84 OsCOPT2 OsHMA5 COPPER RICE
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Role of oncogenic long noncoding RNA KCNQ1OT1 in colon cancer
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作者 GANG LIU lei shi +4 位作者 BIN WANG ZEHUI WU HAIYUAN ZHAO TIANYU ZHAO LIANGHUI shi 《Oncology Research》 SCIE 2024年第3期585-596,共12页
The role of lncRNA KCNQ1 opposite strand/antisense transcript 1(KCNQ1OT1)in colon cancer involves various tumorigenic processes and has been studed widely.However,the mechanism by which it promotes colon cancer remain... The role of lncRNA KCNQ1 opposite strand/antisense transcript 1(KCNQ1OT1)in colon cancer involves various tumorigenic processes and has been studed widely.However,the mechanism by which it promotes colon cancer remains unclear.Retrovirnl vector pSEB61 was retroftted in established HCT116 siKCN and SW480-siKCN cells to silence KCNQ1 OT1.Cellular proliferation was measured using CCK8 assay,and flow cytometry(FCM)detected cell cydle changes.RNA sequencing(RNA Seq)analysis showed differentially expressed genes(DEGs).Gene ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrichment analyses were carried out to analyze enriched functions and signaling pathways.RT-qPCR,immunofluorescence,and western blotting were carried out to validate downstream gene expressions.The effects of tumorigenesis were evaluated in BALB/c nude mice by tumor xenografts.Our data revealed that the silencing of KONQ1OT1 in HCT116 and SW480 cells slowed cell growth and decreased the number of cells in the G2/M phase.RNA-Seq analysis showed the data of DEGs enriched in various GO and KEGG pathways such as DNA replication and cell cyde.RT qPCR,immunofluorescence,and western blotting confirmed downstream CCNE2 and PCNA gene expressions.HCT116 siKCN cells signifcantly suppressed tumorigenesis in BALB/c nude mice.Our study suggests that lncRNA KCNQ1OT1 may provide a promising therapeutic strategy for colon cancer. 展开更多
关键词 lncRNA KCNQ1OT1 Colon cancer HCT116 cells TUMORIGENESIS
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Sm-like 5 knockdown inhibits proliferation and promotes apoptosis of colon cancer cells by upregulating p53,CDKN1A and TNFRSF10B
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作者 Cai-Jing Mo Xiao-Yuan Deng +3 位作者 Ru-Lan Ma Kun Zhu lei shi Kang Li 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第6期2716-2726,共11页
BACKGROUND The role of Sm-like 5(LSM5)in colon cancer has not been determined.In this study,we investigated the role of LSM5 in progression of colon cancer and the potential underlying mechanism involved.AIM To determ... BACKGROUND The role of Sm-like 5(LSM5)in colon cancer has not been determined.In this study,we investigated the role of LSM5 in progression of colon cancer and the potential underlying mechanism involved.AIM To determine the role of LSM5 in the progression of colon cancer and the potential underlying mechanism involved.METHODS The Gene Expression Profiling Interactive Analysis database and the Human Protein Atlas website were used for LSM5 expression analysis and prognosis analysis.Real-time quantitative polymerase chain reaction and Western blotting were utilized to detect the expression of mRNAs and proteins.A lentivirus targeting LSM5 was constructed and transfected into colon cancer cells to silence LSM5 expression.Proliferation and apoptosis assays were also conducted to evaluate the growth of the colon cancer cells.Human GeneChip assay and bioinformatics analysis were performed to identify the potential underlying mechanism of LSM5 in colon cancer.RESULTS LSM5 was highly expressed in tumor tissue and colon cancer cells.A high expression level of LSM5 was related to poor prognosis in patients with colon cancer.Knockdown of LSM5 suppressed proliferation and promoted apoptosis in colon cancer cells.Silencing of LSM5 also facilitates the expression of p53,cyclin-dependent kinase inhibitor 1A(CDKN1A)and tumor necrosis factor receptor superfamily 10B(TNFRSF10B).The inhibitory effect of LSM5 knockdown on the growth of colon cancer cells was associated with the upregulation of p53,CDKN1A and TNFRSF10B.CONCLUSION LSM5 knockdown inhibited the proliferation and facilitated the apoptosis of colon cancer cells by upregulating p53,CDKN1A and TNFRSF10B. 展开更多
关键词 Sm-like 5 Colon cancer PROLIFERATION Apoptosis KNOCKDOWN
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Polycytosine RNA-binding protein 1 regulates osteoblast function via a ferroptosis pathway in type 2 diabetic osteoporosis
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作者 Hong-Dong Ma lei shi +2 位作者 Hai-Tian Li Xin-Dong Wang Mao-Wei Yang 《World Journal of Diabetes》 SCIE 2024年第5期977-987,共11页
BACKGROUND Recently,type 2 diabetic osteoporosis(T2DOP)has become a research hotspot for the complications of diabetes,but the specific mechanism of its occurrence and development remains unknown.Ferroptosis caused by... BACKGROUND Recently,type 2 diabetic osteoporosis(T2DOP)has become a research hotspot for the complications of diabetes,but the specific mechanism of its occurrence and development remains unknown.Ferroptosis caused by iron overload is con-sidered an important cause of T2DOP.Polycytosine RNA-binding protein 1(PCBP1),an iron ion chaperone,is considered a protector of ferroptosis.AIM To investigate the existence of ferroptosis and specific role of PCBP1 in the development of type 2 diabetes.METHODS A cell counting kit-8 assay was used to detect changes in osteoblast viability under high glucose(HG)and/or ferroptosis inhibitors at different concentrations and times.Transmission electron microscopy was used to examine the morpho-logical changes in the mitochondria of osteoblasts under HG,and western blotting was used to detect the expression levels of PCBP1,ferritin,and the ferroptosis-related protein glutathione peroxidase 4(GPX4).A lentivirus silenced and overex-pressed PCBP1.Western blotting was used to detect the expression levels of the osteoblast functional proteins osteoprotegerin(OPG)and osteocalcin(OCN),whereas flow cytometry was used to detect changes in reactive oxygen species(ROS)levels in each group.RESULTS Under HG,the viability of osteoblasts was considerably decreased,the number of mitochondria undergoing atrophy was considerably increased,PCBP1 and ferritin expression levels were increased,and GPX4 expression was decreased.Western blotting results demonstrated that infection with lentivirus overexpressing PCBP1,increased the expression levels of ferritin,GPX4,OPG,and OCN,compared with the HG group.Flow cytometry results showed a reduction in ROS,and an opposite result was obtained after silencing PCBP1.CONCLUSION PCBP1 may protect osteoblasts and reduce the harm caused by ferroptosis by promoting ferritin expression under a HG environment.Moreover,PCBP1 may be a potential therapeutic target for T2DOP. 展开更多
关键词 Polycytosine RNA-binding protein 1 Ferroptosis Reactive oxygen species FERRITIN OSTEOBLAST Type 2 diabetic osteoporosis
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Development and validation of a nomogram for predicting in-hospital mortality of intensive care unit patients with liver cirrhosis
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作者 Xiao-Wei Tang Wen-Sen Ren +6 位作者 Shu Huang Kang Zou Huan Xu Xiao-Min shi Wei Zhang lei shi Mu-Han Lü 《World Journal of Hepatology》 2024年第4期625-639,共15页
BACKGROUND Liver cirrhosis patients admitted to intensive care unit(ICU)have a high mortality rate.AIM To establish and validate a nomogram for predicting in-hospital mortality of ICU patients with liver cirrhosis.MET... BACKGROUND Liver cirrhosis patients admitted to intensive care unit(ICU)have a high mortality rate.AIM To establish and validate a nomogram for predicting in-hospital mortality of ICU patients with liver cirrhosis.METHODS We extracted demographic,etiological,vital sign,laboratory test,comorbidity,complication,treatment,and severity score data of liver cirrhosis patients from the Medical Information Mart for Intensive Care IV(MIMIC-IV)and electronic ICU(eICU)collaborative research database(eICU-CRD).Predictor selection and model building were based on the MIMIC-IV dataset.The variables selected through least absolute shrinkage and selection operator analysis were further screened through multivariate regression analysis to obtain final predictors.The final predictors were included in the multivariate logistic regression model,which was used to construct a nomogram.Finally,we conducted external validation using the eICU-CRD.The area under the receiver operating characteristic curve(AUC),decision curve,and calibration curve were used to assess the efficacy of the models.RESULTS Risk factors,including the mean respiratory rate,mean systolic blood pressure,mean heart rate,white blood cells,international normalized ratio,total bilirubin,age,invasive ventilation,vasopressor use,maximum stage of acute kidney injury,and sequential organ failure assessment score,were included in the multivariate logistic regression.The model achieved AUCs of 0.864 and 0.808 in the MIMIC-IV and eICU-CRD databases,respectively.The calibration curve also confirmed the predictive ability of the model,while the decision curve confirmed its clinical value.CONCLUSION The nomogram has high accuracy in predicting in-hospital mortality.Improving the included predictors may help improve the prognosis of patients. 展开更多
关键词 Liver cirrhosis Intensive care unit NOMOGRAM Predicting model MORTALITY
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扭曲型酰胺——结构与功能
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作者 史雷 詹梓烨 余志友 《大学化学》 CAS 2024年第1期111-118,共8页
酰胺作为具有独特物理化学性质和生物活性的含氮化合物,其在医药、材料等领域已展现出了广泛的应用前景。与传统酰胺相比,扭曲型酰胺由于其分子内的p–π共轭被不同程度地破坏,致使酰胺平面结构发生不同程度的扭曲,进而呈现出独特的反... 酰胺作为具有独特物理化学性质和生物活性的含氮化合物,其在医药、材料等领域已展现出了广泛的应用前景。与传统酰胺相比,扭曲型酰胺由于其分子内的p–π共轭被不同程度地破坏,致使酰胺平面结构发生不同程度的扭曲,进而呈现出独特的反应活性。扭曲角τ和角锥化参数χN是衡量扭曲型酰胺扭曲程度的两个重要指标,τ描述了N―C(O)键的扭曲程度,χN则描述了氮原子的角锥化程度。τ=40°,χN=40°更是其在反应性上区别平面酰胺的关键阈值。本文着重介绍了当τ>40°,χN>40°时环状扭曲型酰胺和无环扭曲型酰胺的特殊结构与反应性能。 展开更多
关键词 扭曲型酰胺 扭曲角 角锥化参数
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Modeling of the height–diameter relationship using an allometric equation model:a case study of stands of Phyllostachys edulis 被引量:1
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作者 Xuan Gao Zhandong Li +5 位作者 Hongmei Yu Zehui Jiang Chen Wang Yu Zhang Lianghua Qi lei shi 《Journal of Forestry Research》 SCIE CAS CSCD 2016年第2期339-347,共9页
Understanding the relationship between tree height (H) and diameter at breast height (D) is vital to forest design, monitoring and biomass estimation. We developed an allometric equation model and tested its appli... Understanding the relationship between tree height (H) and diameter at breast height (D) is vital to forest design, monitoring and biomass estimation. We developed an allometric equation model and tested its applicability for unevenly aged stands of moso bamboo forest at a regional scale. Field data were collected for 21 plots. Based on these data, we identified two strong power relationships: a corre- lation between the mean bamboo height (Hm) and the upper mean H (Hu), and a correlation between the mean D (Din) and the upper mean D (Du). Simulation results derived from the aUometric equation model were in good agreement with observed culms derived from the field data for the 21 stands, with a root-mean-square error and relative root-mean-square error of 1.40 m and 13.41%, respectively. These results demonstrate that the allometric equation model had a strong predictive power in the unevenly aged stands at a regional scale. In addition, the estimated average height-diameter (H-D) model for South Anhui Province was used to predict H for the same type of bamboo in Hunan Province based on the measured D, and the results were highly similar. The allometric equation model has multiple uses at the regional scale, including the evaluation of the variation in the H- D relationship among regions. The model describes the average H-D relationship without considering the effects caused by variation in site conditions, tree density and other factors. 展开更多
关键词 Allometric equation Bamboo Height-diameter relationship MODEL Phyllostachys edulis POACEAE STRATIFICATION
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Preliminary Exploration of the Clinical Features and Immunological Correlation between TIGIT and Esophageal Squamous Cell Carcinoma
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作者 lei shi Zhongling Luo +2 位作者 Huanhuan Tian Yinghui Hao Wenping Zhang 《Journal of Biosciences and Medicines》 2023年第4期350-362,共13页
Objective: To analyze the relationship between TIGIT and clinical features of Esophageal Squamous Cell Carcinoma, we use transcriptomic data from the TCGA database, and to investigate the relationship between TIGIT an... Objective: To analyze the relationship between TIGIT and clinical features of Esophageal Squamous Cell Carcinoma, we use transcriptomic data from the TCGA database, and to investigate the relationship between TIGIT and the immune microenvironment of Esophageal Squamous Cell Carcinoma, to provide a basis for improving the treatment strategy and prognosis of patients with Esophageal Squamous Cell Carcinoma. Methods: RNA sequencing data and clinical data corresponding to cancer tissues were obtained from the TCGA database for Esophageal carcinoma, Esophageal Squamous Cell Carcinoma tissues, and paraneoplastic tissues;then we analyzed the differences in TIGIT expression in Esophageal carcinoma, Esophageal Squamous Cell Carcinoma, and normal esophageal tissues;then we analyzed the relationship between TIGIT expression levels and overall survival in Esophageal Squamous Cell Carcinoma;finally, we explored the relationship between TIGIT expression levels and overall survival in Esophageal Squamous Cell Carcinoma. We investigated the relationship between TIGIT and the tumor immune microenvironment of Esophageal Squamous Cell Carcinoma by tumor immune infiltration and functional enrichment analysis. Results: Our study revealed that TIGIT was highly expressed in Esophageal Squamous Cell Carcinoma, and patients with high TIGIT expression had worse overall survival. We also found a close relationship between TIGIT expression levels and the immune microenvironment of Esophageal Squamous Cell Carcinoma, with high TIGIT expression positively correlated with multiple immune cells. Conclusion: Our study demonstrates that TIGIT is associated with Esophageal Squamous Cell Carcinoma malignancy and is closely linked to the immune microenvironment. Furthermore, high expression of TIGIT often predicts poorer clinical features. 展开更多
关键词 Esophageal Squamous Cell Carcinoma TIGIT DATABASE Immunogene Tumour Immune Microenvironment
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Evaluation of injuries caused by coronavirus disease 2019 using multi-nuclei magnetic resonance imaging 被引量:1
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作者 Qian Zhou Qiuchen Rao +5 位作者 Haidong Li Ming Zhang Xiuchao Zhao lei shi Chaohui Ye Xin Zhou 《Magnetic Resonance Letters》 2021年第1期2-10,共9页
The ongoing pandemic of coronavirus disease 2019(COVID-19)has been a great burden for the healthcare system in many countries because of its high transmissibility,severity,and fatality.Chest radiography and computed t... The ongoing pandemic of coronavirus disease 2019(COVID-19)has been a great burden for the healthcare system in many countries because of its high transmissibility,severity,and fatality.Chest radiography and computed tomography(CT)play a vital role in the diagnosis,detection of complications,and prognostication of COVID-19.Additionally,magnetic resonance imaging(MRI),especially multi-nuclei MRI,is another important imaging technique for disease diagnosis because of its good soft tissue contrast and the ability to conduct structural and functional imaging,which has also been used to evaluate COVID-19-related organ injuries in previous studies.Herein,we briefly reviewed the recent research on multi-nuclei MRI for evaluating injuries caused by COVID-19 and the clinical 1 H MRI techniques and their applications for assessing injuries in lungs,brain,and heart.Moreover,the emerging hyperpolarized 129Xe gas MRI and its applications in the evaluation of pulmonary structures and functional abnormalities caused by COVID-19 were also reviewed. 展开更多
关键词 COVID-19 Multi-nuclei MRI Hyperpolarized 129Xe LUNG Brain Heart
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乡村短视频的空间建构与生产动力
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作者 石磊 秦洋洋 《新媒体与社会》 2023年第3期279-288,397,共11页
近年来乡村短视频兴起,成为乡土中国的新名片。本文以2021年11月1日至2022年11月30日为时间线,选取了国内10名代表性乡村短视频创作者的692条乡村短视频进行研究。这些短视频建构了4种乡村空间,即劳动生产空间、日常生活空间、社会交往... 近年来乡村短视频兴起,成为乡土中国的新名片。本文以2021年11月1日至2022年11月30日为时间线,选取了国内10名代表性乡村短视频创作者的692条乡村短视频进行研究。这些短视频建构了4种乡村空间,即劳动生产空间、日常生活空间、社会交往空间、文化空间。乡村空间生产具有政策、技术、资本和受众4种动力,它们共同推动乡村空间的建构,将乡村空间“可见”的“可能”变成现实。乡村短视频实现了乡村空间的价值重构与关系再生产,为乡村振兴提供了新的实现路径与媒体力量。 展开更多
关键词 乡村短视频 空间建构 生成动力 乡村振兴
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Constraining the crustal structure under the central and western Tian Shan based on teleseismic receiver functions and gravity anomalies 被引量:2
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作者 Yonghua Li Hanhan Tang lei shi 《Earthquake Science》 2023年第1期1-14,共14页
The Tian Shan is a vast range that spans several countries in Asia.Understanding its evolutionary history may provide valuable insights into intracontinental orogenic dynamics.In this study,we explored the crustal cha... The Tian Shan is a vast range that spans several countries in Asia.Understanding its evolutionary history may provide valuable insights into intracontinental orogenic dynamics.In this study,we explored the crustal characteristics of the Tian Shan and their relationships to the tectonic evolution of the region.A new H-stacking method that combines the P receiver function and gravity anomalies was used to estimate the thickness and ratio of P-to S-wave velocities(Vp/Vs)for 91 broadband seismic stations in the central and western Tian Shan.Our results revealed significant lateral variations in crustal thickness and Vp/Vs.A—45-km-thick crust and an intermediate-high Vp/Vs(-1.74-1.84)were found in the Kazakh Shield and Tarim Basin,which we interpreted to indicate a mafic crystalline basement and lower crust.The central Tian Shan varied greatly in crustal thickness(40-64 km)and Vp/Vs ratio(1.65-2.00).which may be due to crustal shortening,mafic underplating,and crustal melting.In contrast,we observed a relatively thin crust(42-50 km)with an intermediate Vp/Vs ratio(-1.78)in the western Tian Shan.The differences in the crustal structures between the western and central Tian Shan imply that the Talas-Fergana Fault may be trans-lithospheric. 展开更多
关键词 Tian Shan crustal thickness crustal composition receiver function gravity anomaly
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Two-dimensional nanomaterials confined single atoms: New opportunities for environmental remediation 被引量:1
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作者 Yu Yin lei shi +4 位作者 Shu Zhang Xiaoguang Duan Jinqiang Zhang Hongqi Sun Shaobin Wang 《Nano Materials Science》 EI CAS CSCD 2023年第1期15-38,共24页
Two-dimensional(2D)supports confined single-atom catalysts(2D SACs)with unique geometric and electronic structures have been attractive candidates in different catalytic applications,such as energy conversion and stor... Two-dimensional(2D)supports confined single-atom catalysts(2D SACs)with unique geometric and electronic structures have been attractive candidates in different catalytic applications,such as energy conversion and storage,value-added chemical synthesis and environmental remediation.However,their environmental appli-cations lack of a comprehensive summary and in-depth discussion.In this review,recent progresses in synthesis routes and advanced characterization techniques for 2D SACs are introduced,and a comprehensive discussion on their applications in environmental remediation is presented.Generally,2D SACs can be effective in catalytic elimination of aqueous and gaseous pollutants via radical or non-radical routes and transformation of toxic pollutants into less poisonous species or highly value-added products,opening a new horizon for the contami-nant treatment.In addition,in-depth reaction mechanisms and potential pathways are systematically discussed,and the relationship between the structure-performance is highlighted.Finally,several critical challenges within this field are presented,and possible directions for further explorations of 2D SACs in environmental remediation are suggested.Although the research of 2D SACs in the environmental application is still in its infancy,this review will provide a timely summary on the emerging field,and would stimulate tremendous interest for designing more attractive 2D SACs and promoting their wide applications. 展开更多
关键词 Single-atom catalysis Two-dimensional material Advanced oxidation process Degradation Transformation Industrial wastewater
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Effect of rare earth on morphology and dispersion of TiB2 phase in Al-Ti-B alloy refiner 被引量:1
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作者 Zhi-qiang Chen Wen-xin Hu +1 位作者 lei shi Wei Wang 《China Foundry》 SCIE CAS CSCD 2023年第2期115-124,共10页
To investigate the effect of rare earth on size and distribution of TiB2 phase in aluminum alloy refiner,Al-5Ti-1B-RE master alloy was fabricated,and its microstructure and phase constitutions were investigated by the... To investigate the effect of rare earth on size and distribution of TiB2 phase in aluminum alloy refiner,Al-5Ti-1B-RE master alloy was fabricated,and its microstructure and phase constitutions were investigated by the combination of first principles calculations and experimental investigation.The calculated results reveal that Ce has the most effective modification ability due to the most positive adsorption energy and the largest charge transfer value compared with other rare earth elements.Results of experimental investigation indicate that the addition of rare earth in the Al-5Ti-1B alloys can greatly refine the particle size of TiB2,improve the distribution of particles and lead to better refinement effect than that of the Al-5Ti-1B alloys without rare earth.Moreover,Ce has the best optimization effect,which agrees well with the calculated results. 展开更多
关键词 Al-Ti-B refiner rare earth TIB2 distribution
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零相频下离子导体的焦耳加热及其电解反应抑制
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作者 石磊 韩宗益 +4 位作者 冯逸轩 张长庚 张祺 朱贺 朱世平 《Engineering》 SCIE EI CAS CSCD 2023年第6期138-143,M0006,共7页
众所周知,当电流通过导体时,会产生热。虽然我们日常生活和工业中的各种应用都是利用电子导体的加热,但很少有人注意到离子导体在加热方面的潜力。这是因为“不可避免的”电化学反应,这可能导致不必要的导体电解,电极腐蚀和表面污垢。... 众所周知,当电流通过导体时,会产生热。虽然我们日常生活和工业中的各种应用都是利用电子导体的加热,但很少有人注意到离子导体在加热方面的潜力。这是因为“不可避免的”电化学反应,这可能导致不必要的导体电解,电极腐蚀和表面污垢。本文报道了离子导体在没有电化学反应的情况下的焦耳加热。采用零相频率的电来抑制高压下离子导体的电解。用各种离子导体,液体和固体,展示了高效的能量转换,而不需要电化学反应。这种加热方法简单、直接、快速、清洁、均匀,在众多工业和家庭应用中具有巨大的潜力。 展开更多
关键词 电化学反应 离子导体 电子导体 焦耳加热 能量转换 电解反应 加热方法 电极腐蚀
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