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ZIF-8有机框架衍生的D-ZnO@Fe_(x)O_(y)S型异质结用于光辅助铀还原
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作者 谢禹志 汪鹏 +7 位作者 董欢欢 王瑞祥 张福城 于杭鑫 赵乙丁 张永翔 竹文坤 陈涛 《核化学与放射化学》 CAS CSCD 北大核心 2024年第4期345-357,I0002,共14页
光催化辅助铀提取作为一种新型的铀提取技术,有望克服传统工艺中多种金属离子与U(Ⅵ)的竞争配位以及富集容量有限的难题。在这项研究中,以ZIF-8为前驱体,通过浸渍和高温热解制备了S型ZIF-8衍生氧化锌@铁氧化物(D-ZnO@Fe_(x)O_(y))异质结... 光催化辅助铀提取作为一种新型的铀提取技术,有望克服传统工艺中多种金属离子与U(Ⅵ)的竞争配位以及富集容量有限的难题。在这项研究中,以ZIF-8为前驱体,通过浸渍和高温热解制备了S型ZIF-8衍生氧化锌@铁氧化物(D-ZnO@Fe_(x)O_(y))异质结,用于光辅助还原铀矿废水中的U(Ⅵ)。相比于铁氧化物(Fe_(x)O_(y))和ZIF-8衍生ZnO(D-ZnO),S型异质结D-ZnO@Fe_(x)O_(y)在竞争离子存在下,表现出优异的光辅助铀还原能力(>95%)。通过能带计算证实了在异质结界面形成内置电场,能够有效增强电子定向迁移,并为促进铀的光辅助还原提供了强大的驱动力。机理研究表明,羟基自由基和超氧自由基是参与光催化还原U(Ⅵ)的主要物质。本研究为探索具有高效光电子分离功能的光催化剂还原U(Ⅵ)提供了一条有价值的途径。 展开更多
关键词 S型异质结 光催化 ZIF-8 铀还原
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MnO_(2)-ZIF-8-SiO_(2)多孔纳米纤维的制备及甲醛催化性能研究
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作者 翟梅青 蒋何鹏 +2 位作者 冯林 张如全 胡敏 《纺织工程学报》 2024年第2期19-27,共9页
为解决较低甲醛浓度下纳米催化材料效率低的问题,设计了集甲醛吸附降解催化于一体的功能型复合纳米纤维材料,以提高对甲醛的催化效率。通过水热原位生长法在SiO_(2)纳米纤维上生长ZIF-8纳米颗粒,并采用原位合成法合成水钠锰矿型MnO_(2)... 为解决较低甲醛浓度下纳米催化材料效率低的问题,设计了集甲醛吸附降解催化于一体的功能型复合纳米纤维材料,以提高对甲醛的催化效率。通过水热原位生长法在SiO_(2)纳米纤维上生长ZIF-8纳米颗粒,并采用原位合成法合成水钠锰矿型MnO_(2)制备出MnO_(2)-ZIF-8-SiO_(2)多孔纳米纤维材料。研究ZIF-8纳米颗粒与水钠锰矿型MnO_(2)协同催化降解甲醛性能,结果表明:ZIF-8-SiO_(2)在生长8 h时,纤维上的ZIF-8呈现立方体结构且分布均匀为较佳生长时间;此外在浴比为1:1000时,通过动力学分析MnO_(2)-ZIF-8-SiO_(2)多孔纳米纤维材料动力学常数k达1.72×10^(-1)h^(-1),并且甲醛降解率可达72.2%,说明纤维材料负载ZIF-8后的MnO_(2)-ZIF-8-SiO_(2)多孔纳米纤维材料对甲醛的降解性能较好。 展开更多
关键词 静电纺丝 水钠锰矿型Mno_(2) ZIF-8纳米颗粒 纳米纤维材料 甲醛降解
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射频等离子体改性制备S_(2)O_(2)-8/SnO_(2)-Al_(2)O_(3)固体超强酸催化剂的研究
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作者 张旭东 李秀兰 +2 位作者 朱长辉 田保河 朱文超 《现代化工》 CAS CSCD 北大核心 2024年第7期139-144,共6页
采用低温陈化法制备S_(2)O_(2)-8/SnO_(2)-Al_(2)O_(3)固体超强酸催化剂,利用射频等离子体技术对其进行改性后催化L-酪氨酸与甲醇的酯化反应。利用Hammett指示剂法、XRD、HRTEM、BET、FT-IR、Py-IR和NH_(3)-TPD等对改性前后的催化剂进... 采用低温陈化法制备S_(2)O_(2)-8/SnO_(2)-Al_(2)O_(3)固体超强酸催化剂,利用射频等离子体技术对其进行改性后催化L-酪氨酸与甲醇的酯化反应。利用Hammett指示剂法、XRD、HRTEM、BET、FT-IR、Py-IR和NH_(3)-TPD等对改性前后的催化剂进行表征。结果表明,经射频等离子体改性后的催化剂颗粒分散性更好、粒径更小(4.32 nm)、比表面积更大(104.4 m^(2)/g)、总酸量更高(142.9μmol/g)。在温度为180℃、压力为1 MPa的条件下,射频等离子体改性后的催化剂催化L-酪氨酸甲酯化反应6 h后L-酪氨酸甲酯产率可达92%。 展开更多
关键词 固体超强酸 S_(2)O_(2)-8/Sno_(2)-Al_(2)O_(3) 射频等离子体 酯化反应
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qGW11a/OsCAT8,encoding an amino acid permease,negatively regulates grain size and weight in rice
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作者 Peng Gao Feifan Chen +16 位作者 Haitang Liu Shijun Fan Jierui Zeng Xue Diao Yang Liu Wencheng Song Shifu Wang Jing Li Xiaobo Zhu Bin Tu Weilan Chen Ting Li Yuping Wang Bingtian Ma Shigui Li Hua Yuan Peng Qin 《The Crop Journal》 SCIE CSCD 2024年第4期1150-1158,共9页
Grain size is a key factor influencing grain weight in rice.In this study,a chromosome segment substitution line(CSSL9-17)was identified,that exhibits a significant reduction in both grain size and weight compared to ... Grain size is a key factor influencing grain weight in rice.In this study,a chromosome segment substitution line(CSSL9-17)was identified,that exhibits a significant reduction in both grain size and weight compared to its donor parent 93-11.Further investigation identified two quantitative trait loci(QTL)on chromosome 11,designated qGW11a and qGW11b,which contribute to 1000-grain weight with an additive effect.LOC_Os11g05690,encoding the amino acid permease OsCAT8,is the target gene of qGW11a.Overexpression of OsCAT8 resulted in decreased grain weight,while OsCAT8 knockout mutants exhibited increased grain weight.The 287-bp located within the OsCAT8 promoter region of 93-11 negatively regulates its activity,which is subsequently correlated with an increase in grain size and weight.These results suggest that OsCAT8 functions as a negative regulator of grain size and grain weight in rice. 展开更多
关键词 RICE Grain size Grain weight QTL OsCAT8
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Predicting the Prognosis and Immunotherapeutic Response of Triple-Negative Breast Cancer by Constructing a Prognostic Model Based on CD8+T Cell-Related Immune Genes
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作者 Nani Li Xiaoting Qiu +3 位作者 Jingsong Xue Limu Yi Mulan Chen Zhijian Huang 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第6期581-593,共13页
Objective Triple-negative breast cancer(TNBC)poses a significant challenge for treatment efficacy.CD8+T cells,which are pivotal immune cells,can be effectively analyzed for differential gene expression across diverse ... Objective Triple-negative breast cancer(TNBC)poses a significant challenge for treatment efficacy.CD8+T cells,which are pivotal immune cells,can be effectively analyzed for differential gene expression across diverse cell populations owing to rapid advancements in sequencing technology.By leveraging these genes,our objective was to develop a prognostic model that accurately predicts the prognosis of patients with TNBC and their responsiveness to immunotherapy.Methods Sample information and clinical data of TNBC were sourced from The Cancer Genome Atlas and METABRIC databases.In the initial stage,we identified 67 differentially expressed genes associated with immune response in CD8+T cells.Subsequently,we narrowed our focus to three key genes,namely CXCL13,GBP2,and GZMB,which were used to construct a prognostic model.The accuracy of the model was assessed using the validation set data and receiver operating characteristic(ROC)curves.Furthermore,we employed various methods,including Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway,immune infiltration,and correlation analyses with CD274(PD-L1)to explore the model's predictive efficacy in immunotherapeutic responses.Additionally,we investigated the potential underlying biological pathways that contribute to divergent treatment responses.Results We successfully developed a model capable of predicting the prognosis of patients with TNBC.The areas under the curve(AUC)values for the 1-,3-,and 5-year survival predictions were 0.618,0.652,and 0.826,respectively.Employing this risk model,we stratified the samples into high-and low-risk groups.Through KEGG enrichment analysis,we observed that the high-risk group predominantly exhibited enrichment in metabolism-related pathways such as drug and chlorophyll metabolism,whereas the low-risk group demonstrated significant enrichment in cytokine pathways.Furthermore,immune landscape analysis revealed noteworthy variations between(PD-L1)expression and risk scores,indicating that our model effectively predicted the response of patients to immune-based treatments.Conclusion Our study demonstrates the potential of CXCL13,GBP2,and GZMB as prognostic indicators of clinical outcomes and immunotherapy responses in patients with TNBC.These findings provide valuable insights and novel avenues for developing immunotherapeutic approaches targeting TNBC. 展开更多
关键词 Breast Cancer IMMUnoTHERAPY PROGnoSIS CD8+T cells PD-L1
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Identification of prognostic molecular subtypes and model based on CD8+ T cells for lung adenocarcinoma
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作者 HONGMIN CAO YING XUE +3 位作者 FEI WANG GUANGYAO LI YULAN ZHEN JINGWEN GUO 《BIOCELL》 SCIE 2024年第3期473-490,共18页
Background:Cytotoxic T lymphocytes(CD8+T)cells function critically in mediating anti-tumor immune response in cancer patients.Characterizing the specific functions of CD8+T cells in lung adenocarcinoma(LUAD)could help ... Background:Cytotoxic T lymphocytes(CD8+T)cells function critically in mediating anti-tumor immune response in cancer patients.Characterizing the specific functions of CD8+T cells in lung adenocarcinoma(LUAD)could help better understand local anti-tumor immune responses and estimate the effect of immunotherapy.Methods:Gens related to CD8+T cells were identified by cluster analysis based on the single-cell sequencing data of three LUAD tissues and their paired normal tissues.Weighted gene co-expression network analysis(WGCNA),consensus clustering,differential expression analysis,least absolute shrinkage and selection operator(LASSO)and Cox regression analysis were conducted to classify molecular subtypes for LUAD and to develop a risk model using prognostic genes related to CD8+T cells.Expression of the genes in the prognostic model,their effects on tumor cell invasion,and interactions with CD8+T cells were verified by cell experiments.Results:This study defined two LUAD clusters(CD8+0 and CD8+1)based on CD8+T cells,with cluster CD8+0 being significantly associated with the prognosis of LUAD.Three heterogeneous subtypes(clusters 1,2,and 3)differing in prognosis,genome mutation events,and immune status were categorized using 42 prognostic genes.A prognostic model created based on 11 significant genes(including CD200R1,CLEC17A,ZC3H12D,GNG7,SNX30,CDCP1,NEIL3,IGF2BP1,RHOV,ABCC2,and KRT81)was able to independently estimate the death risk for patients in different LUAD cohorts.Moreover,the model also showed general applicability in external validation cohorts.Low-risk patients could benefit more from taking immunotherapy and were significantly related to the resistance to anticancer drugs.The results from cell experiments demonstrated that the expression of CD200R1,CLEC17A,ZC3H12D,GNG7,and SNX30 was significantly downregulated,while that of CDCP1,NEIL3,IGF2BP1,RHOV,ABCC2 and KRT81 was upregulated in LUAD cells.Inhibition of CD200R1 greatly increased the invasiveness of the LUAD cells,but inhibiting CDCP1 expression weakened the invasion ability of LUAD cells.Conclusion:This study defined two prognostic CD8+T cell clusters and classified three heterogeneous molecular subtypes for LUAD.A prognostic model predictive of the potential effects of immunotherapy on LUAD patients was developed. 展开更多
关键词 CD8+T cell Lung adenocarcinoma Molecular subtype Prognostic model IMMUnoTHERAPY
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An 8-Node Plane Hybrid Element for StructuralMechanics Problems Based on the Hellinger-Reissner Variational Principle
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作者 Haonan Li WeiWang +1 位作者 Quan Shen Linquan Yao 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第2期1277-1299,共23页
The finite element method (FEM) plays a valuable role in computer modeling and is beneficial to the mechanicaldesign of various structural parts. However, the elements produced by conventional FEM are easily inaccurat... The finite element method (FEM) plays a valuable role in computer modeling and is beneficial to the mechanicaldesign of various structural parts. However, the elements produced by conventional FEM are easily inaccurate andunstable when applied. Therefore, developing new elements within the framework of the generalized variationalprinciple is of great significance. In this paper, an 8-node plane hybrid finite element with 15 parameters (PHQ8-15β) is developed for structural mechanics problems based on the Hellinger-Reissner variational principle.According to the design principle of Pian, 15 unknown parameters are adopted in the selection of stress modes toavoid the zero energy modes.Meanwhile, the stress functions within each element satisfy both the equilibrium andthe compatibility relations of plane stress problems. Subsequently, numerical examples are presented to illustrate theeffectiveness and robustness of the proposed finite element. Numerical results show that various common lockingbehaviors of plane elements can be overcome. The PH-Q8-15β element has excellent performance in all benchmarkproblems, especially for structures with varying cross sections. Furthermore, in bending problems, the reasonablemesh shape of the new element for curved edge structures is analyzed in detail, which can be a useful means toimprove numerical accuracy. 展开更多
关键词 8-node plane hybrid element Hellinger-Reissner variational principle locking behaviors structural mechanics problems
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High patatin like phospholipase domain containing 8 expression as a biomarker for poor prognosis of colorectal cancer
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作者 Peng-Yang Zhou De-Xiang Zhu +4 位作者 Yi-Jiao Chen Qing-Yang Feng Yi-Hao Mao Ao-Bo Zhuang Jian-Min Xu 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第3期787-797,共11页
BACKGROUND Patatin like phospholipase domain containing 8(PNPLA8)has been shown to play a significant role in various cancer entities.Previous studies have focused on its roles as an antioxidant and in lipid peroxidat... BACKGROUND Patatin like phospholipase domain containing 8(PNPLA8)has been shown to play a significant role in various cancer entities.Previous studies have focused on its roles as an antioxidant and in lipid peroxidation.However,the role of PNPLA8 in colorectal cancer(CRC)progression is unclear.AIM To explore the prognostic effects of PNPLA8 expression in CRC.METHODS A retrospective cohort containing 751 consecutive CRC patients was enrolled.PNPLA8 expression in tumor samples was evaluated by immunohistochemistry staining and semi-quantitated with immunoreactive scores.CRC patients were divided into high and low PNPLA8 expression groups based on the cut-off va-lues,which were calculated by X-tile software.The prognostic value of PNPLA8 was identified using univariate and multivariate Cox regression analysis.The over-all survival(OS)rates of CRC patients in the study cohort were compared with Kaplan-Meier analysis and Log-rank test.RESULTS PNPLA8 expression was significantly associated with distant metastases in our cohort(P=0.048).CRC patients with high PNPLA8 expression indicated poor OS(median OS=35.3,P=0.005).CRC patients with a higher PNPLA8 expression at either stage I and II or stage III and IV had statistically significant shorter OS.For patients with left-sided colon and rectal cancer,the survival curves of two PN-PLA8-expression groups showed statistically significant differences.Multivariate analysis also confirmed that high PNPLA8 expression was an independent prog-nostic factor for overall survival(hazard ratio HR=1.328,95%CI:1.016-1.734,P=0.038). 展开更多
关键词 BIOMARKER Colorectal cancer Expression level Overall survival Patatin like phospholipase domain containing 8 Prognosis
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Recombinant adeno-associated virus 8-mediated inhibition of microRNA let-7a ameliorates sclerosing cholangitis in a clinically relevant mouse model
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作者 Hui Hua Qian-Qian Zhao +9 位作者 Miriam Nkesichi Kalagbor Guo-Zhi Yu Man Liu Zheng-Rui Bian Bei-Bei Zhang Qian Yu Yin-Hai Xu Ren-Xian Tang Kui-Yang Zheng Chao Yan 《World Journal of Gastroenterology》 SCIE CAS 2024年第5期471-484,共14页
BACKGROUND Primary sclerosing cholangitis(PSC)is characterized by chronic inflammation and it predisposes to cholangiocarcinoma due to lack of effective treatment options.Recombinant adeno-associated virus(rAAV)provid... BACKGROUND Primary sclerosing cholangitis(PSC)is characterized by chronic inflammation and it predisposes to cholangiocarcinoma due to lack of effective treatment options.Recombinant adeno-associated virus(rAAV)provides a promising platform for gene therapy on such kinds of diseases.A microRNA(miRNA)let-7a has been reported to be associated with the progress of PSC but the potential therapeutic implication of inhibition of let-7a on PSC has not been evaluated.AIM To investigate the therapeutic effects of inhibition of a miRNA let-7a transferred by recombinant adeno-associated virus 8(rAAV8)on a xenobiotic-induced mouse model of sclerosing cholangitis.METHODS A xenobiotic-induced mouse model of sclerosing cholangitis was induced by 0.1% 3,5-Diethoxycarbonyl-1,4-Dihydrocollidine(DDC)feeding for 2 wk or 6 wk.A single dose of rAAV8-mediated anti-let-7a-5p sponges or scramble control was injected in vivo into mice onset of DDC feeding.Upon sacrifice,the liver and the serum were collected from each mouse.The hepatobiliary injuries,hepatic inflammation and fibrosis were evaluated.The targets of let-7a-5p and downstream molecule NF-κB were detected using Western blot.RESULTS rAAV8-mediated anti-let-7a-5p sponges can depress the expression of let-7a-5p in mice after DDC feeding for 2 wk or 6 wk.The reduced expression of let-7a-5p can alleviate hepato-biliary injuries indicated by serum markers,and prevent the proliferation of cholangiocytes and biliary fibrosis.Furthermore,inhibition of let-7a mediated by rAAV8 can increase the expression of potential target molecules such as suppressor of cytokine signaling 1 and Dectin1,which consequently inhibit of NF-κB-mediated hepatic inflammation.CONCLUSION Our study demonstrates that a rAAV8 vector designed for liver-specific inhibition of let-7a-5p can potently ameliorate symptoms in a xenobiotic-induced mouse model of sclerosing cholangitis,which provides a possible clinical translation of PSC of human. 展开更多
关键词 Primary sclerosing cholangitis Recombinant adeno-associated virus 8 Let-7a-5p Therapeutic effects INFLAMMATION
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A Novel Foreign Object Detection Method in Transmission Lines Based on Improved YOLOv8n
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作者 Yakui Liu Xing Jiang +4 位作者 Ruikang Xu Yihao Cui Chenhui Yu Jingqi Yang Jishuai Zhou 《Computers, Materials & Continua》 SCIE EI 2024年第4期1263-1279,共17页
The rapid pace of urban development has resulted in the widespread presence of construction equipment andincreasingly complex conditions in transmission corridors. These conditions pose a serious threat to the safeope... The rapid pace of urban development has resulted in the widespread presence of construction equipment andincreasingly complex conditions in transmission corridors. These conditions pose a serious threat to the safeoperation of the power grid.Machine vision technology, particularly object recognition technology, has beenwidelyemployed to identify foreign objects in transmission line images. Despite its wide application, the technique faceslimitations due to the complex environmental background and other auxiliary factors. To address these challenges,this study introduces an improved YOLOv8n. The traditional stepwise convolution and pooling layers are replacedwith a spatial-depth convolution (SPD-Conv) module, aiming to improve the algorithm’s efficacy in recognizinglow-resolution and small-size objects. The algorithm’s feature extraction network is improved by using a LargeSelective Kernel (LSK) attention mechanism, which enhances the ability to extract relevant features. Additionally,the SIoU Loss function is used instead of the Complete Intersection over Union (CIoU) Loss to facilitate fasterconvergence of the algorithm. Through experimental verification, the improved YOLOv8n model achieves adetection accuracy of 88.8% on the test set. The recognition accuracy of cranes is improved by 2.9%, which isa significant enhancement compared to the unimproved algorithm. This improvement effectively enhances theaccuracy of recognizing foreign objects on transmission lines and proves the effectiveness of the new algorithm. 展开更多
关键词 YOLOv8n data enhancement attention mechanism SPD-Conv Smoothed Intersection over Union(SIoU)Loss
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Double enzyme mimetic activities of multifunctional Ag nanoparticle-decorated Co_(3)V_(2)O_(8)hollow hexagonal prismatic pencils for application in colorimetric sensors and disinfection
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作者 Ying Gao Peng Ju +4 位作者 Yu Zhang Yuxin Zhang Xiaofan Zhai Jizhou Duan Baorong Hou 《Nano Materials Science》 EI CAS CSCD 2024年第2期244-255,共12页
Since the catalytic activity of most nanozymes is still far lower than the corresponding natural enzymes,there is urgent need to discover novel highly efficient enzyme-like materials.In this work,Co_(3)V_(2)O_(8)with ... Since the catalytic activity of most nanozymes is still far lower than the corresponding natural enzymes,there is urgent need to discover novel highly efficient enzyme-like materials.In this work,Co_(3)V_(2)O_(8)with hollow hexagonal prismatic pencil structures were prepared as novel artificial enzyme mimics.They were then decorated by photo-depositing Ag nanoparticles(Ag NPs)on the surface to further improve its catalytic activities.The Ag NPs decorated Co_(3)V_(2)O_(8)(ACVPs)showed both excellent oxidase-and peroxidase-like catalytic activities.They can oxidize the colorless 3,3’,5,5’-tetramethylbenzidine rapidly to induce a blue change.The enhanced enzyme mimetic activities can be attributed to the surface plasma resonance(SPR)effect of Ag NPs as well as the synergistic catalytic effect between Ag NPs and Co_(3)V_(2)O_(8),accelerating electron transfer and promoting the catalytic process.ACVPs were applied in constructing a colorimetric sensor,validating the occurrence of the Fenton reaction,and disinfection,presenting favorable catalytic performance.The enzyme-like catalytic mechanism was studied,indicating the chief role of⋅O_(2)-radicals in the catalytic process.This work not only discovers a novel functional material with double enzyme mimetic activity but also provides a new insight into exploiting artificial enzyme mimics with highly efficient catalytic ability. 展开更多
关键词 Co_(3)V_(2)O_(8) Ag NPs Enzyme mimetic Colorimetric sensor DISINFECTION
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Inhibitory Effect of Flavonoid Glycosides from Chlorophytum comosum on Nasopharyngeal Carcinoma 5-8F Cells and Its Mechanism
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作者 Chenliang CHU Xinchen WANG +2 位作者 Kuan LU Liang QIN Lu JIN 《Medicinal Plant》 2024年第1期66-70,共5页
[Objectives]To study the inhibitory activity of two flavonoid glycosides isolated from Chlorophytum comosum Laxum R.Br on human nasopharyngeal carcinoma(NPC)cell line 5-8F in vitro and its mechanism.[Methods]The flavo... [Objectives]To study the inhibitory activity of two flavonoid glycosides isolated from Chlorophytum comosum Laxum R.Br on human nasopharyngeal carcinoma(NPC)cell line 5-8F in vitro and its mechanism.[Methods]The flavonoid glycosides were isolated and purified from the ethanol alcoholic extract of the roots of Liliaceae plant Chlorophytum comosum by silica gel column chromatography,macroporous resin column chromatography,Sephadex LH-20,and reverse column chromatography(ODS).The inhibitory activity of flavonoid glycosides on human nasopharyngeal carcinoma cells was analyzed by CCK-8 method,and the potential mechanism was preliminarily analyzed by molecular docking.[Results]Two flavonoid glycosides were identified as isovitexin 2″-0-rhamnoside and 7-2″-di-O-β-glucopyranosylisovitexin.Two flavonoid glycosides showed promising inhibitory effect on human nasopharyngeal carcinoma cell line 5-8F,with IC_(50) values of 24.8 and 27.5μmol/L,respectively.Molecular docking results showed that the potential targets of two flavonoid glycosides include CyclinD1,Bcl-2β-Catenin,ILK,TGF-β,in addition,two glycosides showed higher predicted binding affinity towards CyclinD1,which verifies the cytotoxicity of the two compounds on human nasopharyngeal carcinoma cell line 5-8F in vitro.[Conclusions]Two flavonoid glycosides are the active molecules in Chlorophytum comosum that can inhibit the proliferation of human nasopharyngeal carcinoma cells,and have the potential to be used in the research and development of anti nasopharyngeal carcinoma drugs. 展开更多
关键词 Chlorophytum comosum Laxum R.Br. Flavonoid glycosides 5-8F cells Antitumor mechanism
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聚乙烯醇/ZIF-8复合膜的制备及吸附性能 被引量:1
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作者 杨亮 孔韩韩 +6 位作者 李韦霖 孟存飞 王琴 张天芸 王雪梅 李文全 吕庄元 《印染》 CAS 北大核心 2024年第2期72-78,共7页
通过溶液流延法制备了聚乙烯醇/ZIF-8复合膜,采用SEM、FT-IR、XRD、TGA、BET等对聚乙烯醇/ZIF-8复合膜进行表征,并探究了复合膜的水稳定性、机械性能,以及对刚果红(CR)的吸附性能。结果表明:聚乙烯醇与ZIF-8材料复合后能改善聚乙烯醇的... 通过溶液流延法制备了聚乙烯醇/ZIF-8复合膜,采用SEM、FT-IR、XRD、TGA、BET等对聚乙烯醇/ZIF-8复合膜进行表征,并探究了复合膜的水稳定性、机械性能,以及对刚果红(CR)的吸附性能。结果表明:聚乙烯醇与ZIF-8材料复合后能改善聚乙烯醇的热稳定性,增加膜表面粗糙度;吸附过程以化学吸附为主,通过内部扩散控制吸附速率,符合准二级吸附动力学模型和Langmuir吸附曲线;ZIF-8质量分数为10%时制备的聚乙烯醇/ZIF-8复合膜,在温度20℃、刚果红溶液质量浓度95 mg/L时,对刚果红的最大吸附量达159.63 mg/g,使用4次后仍能保持93%的吸附效率。 展开更多
关键词 聚乙烯醇 ZIF-8 复合膜 吸附
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miR-567通过调控CDK8在NSCLC增殖、迁移和细胞周期中的作用及其临床相关性研究 被引量:1
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作者 李海洋 赵振山 +4 位作者 李静 戎瑶 郑爱民 郝孟辉 田发明 《国际检验医学杂志》 CAS 2024年第3期335-340,346,共7页
目的探讨微小RNA(miR)-567通过调控周期蛋白依赖性激酶8(CDK8)在非小细胞肺癌(NSCLC)增殖、迁移和细胞周期中的作用及其临床相关性研究。方法收集40例NSCLC患者的肿瘤组织和临近癌旁组织,采用实时荧光定量PCR(qRT-PCR)检测miR-567和CDK... 目的探讨微小RNA(miR)-567通过调控周期蛋白依赖性激酶8(CDK8)在非小细胞肺癌(NSCLC)增殖、迁移和细胞周期中的作用及其临床相关性研究。方法收集40例NSCLC患者的肿瘤组织和临近癌旁组织,采用实时荧光定量PCR(qRT-PCR)检测miR-567和CDK8的表达。将miR-NC mimic、miR-567 mimic、oe-NC和oe-CDK8转染至A549和H1975细胞中,使用qRT-PCR检测miR-567和CDK8的表达,CCK-8法检测细胞增殖水平,Transwell法检测细胞迁移水平,流式细胞术检测细胞周期变化。通过荧光素酶报告基因实验检测miR-567与CDK8的靶向性。结果在NSCLC患者的肿瘤组织中,miR-567表达降低,而CDK8表达升高,二者呈负相关(P<0.05)。在A549和H1975细胞中,miR-567 mimic组相较于miR-NC mimic组,miR-567表达升高,CDK8表达降低,细胞增殖和迁移水平降低,细胞G1期比例升高,S期比例降低;miR-567 mimic组在正常型CDK8中,荧光强度低于miR-NC mimic组;miR-567 mimic+oe-CDK8组相较于miR-567 mimic+oe-NC组,CDK8表达升高,细胞增殖和迁移水平升高,细胞G1期比例降低,S期比例升高。结论miR-567通过靶向抑制CDK8表达,控制肿瘤细胞在S期阻滞,从而抑制NSCLC的增殖和迁移能力。 展开更多
关键词 非小细胞肺癌 细胞周期 细胞周期蛋白依赖性激酶8 微小RNA-567
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基于改进YOLOv8的无人机航拍图像目标检测算法 被引量:5
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作者 程换新 乔庆元 +1 位作者 骆晓玲 于沙家 《无线电工程》 2024年第4期871-881,共11页
针对现存无人机航拍图像目标检测算法检测精度较低、模型较为复杂的问题,提出一种改进YOLOv8的目标检测算法。在骨干网络引入多尺度注意力EMA,捕捉细节信息,以提高模型的特征提取能力;改进C2f模块,减小模型的计算量。提出了轻量级的Bi-Y... 针对现存无人机航拍图像目标检测算法检测精度较低、模型较为复杂的问题,提出一种改进YOLOv8的目标检测算法。在骨干网络引入多尺度注意力EMA,捕捉细节信息,以提高模型的特征提取能力;改进C2f模块,减小模型的计算量。提出了轻量级的Bi-YOLOv8特征金字塔网络结构改进YOLOv8的颈部,增强了模型多尺度特征融合能力,改善网络对小目标的检测精度。使用WIoU Loss优化原网络损失函数,引入一种动态非单调聚焦机制,提高模型的泛化能力。在无人机航拍数据集VisDrone2019上的实验表明,提出算法的mAP50为40.7%,较YOLOv8s提升了1.5%,参数量降低了42%,同时相比于其他先进的目标检测算法在精度和速度上均有提升,证明了改进算法的有效性和先进性。 展开更多
关键词 航拍图像 小目标检测 YOLOv8 Bi-YOLOv8 轻量化
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基于改进YOLOv8的嵌入式道路裂缝检测算法 被引量:1
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作者 耿焕同 刘振宇 +2 位作者 蒋骏 范子辰 李嘉兴 《计算机应用》 CSCD 北大核心 2024年第5期1613-1618,共6页
在边缘端设备部署YOLOv8L模型进行道路裂缝检测可以实现较高的精度,但难以保证实时检测。针对此问题,提出一种可部署到边缘计算设备Jetson AGX Xavier上的基于改进YOLOv8模型的目标检测算法。首先,利用部分卷积设计Faster Block结构以替... 在边缘端设备部署YOLOv8L模型进行道路裂缝检测可以实现较高的精度,但难以保证实时检测。针对此问题,提出一种可部署到边缘计算设备Jetson AGX Xavier上的基于改进YOLOv8模型的目标检测算法。首先,利用部分卷积设计Faster Block结构以替换YOLOv8 C2f模块中的Bottleneck结构,并将改进后的C2f模块记为C2f-Faster;其次,在YOLOv8主干网络中的每个C2f-Faster模块之后接一个SE(Squeeze-and-Excitation)通道注意力层,进一步提高检测的精度。在开源道路损害数据集RDD20(Road Damage Detection 20)上的实验结果表明:所提方法的平均F1得分为0.573,每秒检测帧数(FPS)为47,模型大小为55.5MB,相较于GRDDC2020(GlobalRoadDamageDetection Challenge 2020)的SOTA(State-Of-The-Art)模型,F1得分提高了0.8个百分点,FPS提高了291.7%,模型大小减小了41.8%,实现了在边缘设备上对道路裂缝实时且准确的检测。 展开更多
关键词 YOLOv8 目标检测 轻量化 注意力机制 道路裂缝
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IRF8靶向铁死亡在急性肺损伤中的作用及机制研究 被引量:1
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作者 王佳 李忻炎 +3 位作者 李琳钰 张晓晶 杨娟 折志刚 《医学新知》 CAS 2024年第4期363-371,共9页
目的探讨干扰素调节因子8(interferon regulatory factor 8,IRF8)在急性肺损伤(acute lung injury,ALI)中的作用及其机制。方法采用实时荧光定量逆转录聚合酶链反应(RT-qPCR)和蛋白免疫印迹(WB)检测体内外ALI模型中IRF8 mRNA和蛋白的表... 目的探讨干扰素调节因子8(interferon regulatory factor 8,IRF8)在急性肺损伤(acute lung injury,ALI)中的作用及其机制。方法采用实时荧光定量逆转录聚合酶链反应(RT-qPCR)和蛋白免疫印迹(WB)检测体内外ALI模型中IRF8 mRNA和蛋白的表达。体外构建稳定过表达和敲低IRF8的A549细胞系,采用RT-qPCR检测炎症相关基因mRNA的表达;WB检测凋亡相关基因的表达。分别选取12只同窝阴性对照小鼠和12只Irf8敲除品系小鼠,构建ALI模型,收集造模后的小鼠肺组织并称重;收集并检测肺泡灌洗液中总细胞数以及总蛋白含量。采用苏木精-伊红染色及免疫荧光分析肺组织炎症浸润情况;利用RT-qPCR检测Irf8敲除小鼠肺组织炎症相关基因mRNA的表达;TUNEL染色分析肺组织凋亡情况;采用WB分别在体内外ALI模型中检测铁死亡相关信号分子的蛋白表达。结果IRF8在体内体外ALI中表达上调;体外敲低IRF8加剧细胞内炎症以及细胞凋亡,反之,过表达IRF8可在体外ALI模型中发挥保护作用;敲除Irf8加重小鼠肺损伤;进一步机制探索发现IRF8通过调控铁死亡相关信号分子表达从而减轻肺损伤。结论IRF8通过靶向铁死亡在肺损伤中发挥保护作用,为肺损伤的治疗提供潜在靶点。 展开更多
关键词 IRF8 急性肺损伤 铁死亡 炎症 凋亡
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葵花-8卫星AOD资料在CMA-MESO/CUACE
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作者 田伟红 庄照荣 +1 位作者 韩威 沈学顺 《高原气象》 CSCD 北大核心 2024年第5期1259-1270,共12页
CMA-MESO/CUACE CW化学天气耦合模式是自主研发的大气化学耦合模式,目前CMA-MESO/CUACE CW3DVar同化系统实现了地面气溶胶观测可吸入颗粒物PM_(2.5)和PM10的同化,为增强耦合同化系统非常规观测的同化能力,文中在CMA-MESO大气化学天气耦... CMA-MESO/CUACE CW化学天气耦合模式是自主研发的大气化学耦合模式,目前CMA-MESO/CUACE CW3DVar同化系统实现了地面气溶胶观测可吸入颗粒物PM_(2.5)和PM10的同化,为增强耦合同化系统非常规观测的同化能力,文中在CMA-MESO大气化学天气耦合三维变分同化框架基础上,利用查表法获得气溶胶消光系数,然后建立气溶胶光学厚度(AerosolOpticalDepth,AOD)和气溶胶组分之间关系的观测算子、切线性观测算子和伴随观测算子,实现AOD观测资料的同化应用。针对2016年12月18-20日华北、黄淮地区一次污染天气过程进行同化预报试验,试验结果表明同化葵花-8卫星(Hi‐mawari-8)气溶胶光学厚度观测后,PM_(2.5)分析的重污染区范围有所扩大,山西东南部分析与实况分布更为接近,但是山东大部地区PM_(2.5)分析偏强,与观测相比PM_(2.5)质量浓度存在高估。同时同化Himawari-8 AOD观测和地面气溶胶站点观测的PM_(2.5)分析最优,分析与观测距平相关系数最高,平均偏差、均方根误差及标准差最小。重污染区的PM_(2.5)预报检验结果表明,同化Himawari-8AOD观测对大于350µg·m^(-3)量级PM_(2.5)预报正贡献可以持续到48 h,但整体来说,同时同化Himawari-8AOD观测和地面气溶胶站点观测对各个量级的PM_(2.5)质量浓度预报质量最优。 展开更多
关键词 气溶胶光学厚度观测(AOD) CMA-MESO三维变分 CUACE 葵花-8(Himawari-8)
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ZIF-8@TiO_(2)复合材料的制备及光催化性能
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作者 涂盛辉 钟荣福 +3 位作者 张超 刘桉如 吴文彬 杜军 《材料导报》 EI CAS CSCD 北大核心 2024年第16期29-34,共6页
本研究采用水热法制备了一种新型的高效光催化微米复合材料ZIF-8@TiO_(2),并比较了ZIF-8、TiO_(2)纳米球和ZIF-8@TiO_(2)光催化降解罗丹明B的能力。通过扫描电子显微镜(SEM)、X射线衍射(XRD)仪、X射线光电子能谱(XPS)仪、紫外-可见漫反... 本研究采用水热法制备了一种新型的高效光催化微米复合材料ZIF-8@TiO_(2),并比较了ZIF-8、TiO_(2)纳米球和ZIF-8@TiO_(2)光催化降解罗丹明B的能力。通过扫描电子显微镜(SEM)、X射线衍射(XRD)仪、X射线光电子能谱(XPS)仪、紫外-可见漫反射光谱(DRS)仪、傅里叶变换红外光谱(FTIR)仪和比表面积测量(BET)仪对合成的材料进行了表征。结果表明,TiO_(2)纳米球在ZIF-8表面均匀生长,ZIF-8和TiO_(2)通过化学键连接在一起。ZIF-8和TiO_(2)的协同作用大大增强了复合光催化剂的催化能力。其中ZIF-8@TiO_(2)复合材料的ZIF-8为电荷分离器中光生电子转移提供了一种新的方式,以降低电荷复合率。由于该混合物结合了ZIF-8和TiO_(2)的优点,ZIF-8@TiO_(2)显示出优异的光催化降解罗丹明B的能力。同时讨论了复合光催化剂可能的光催化机理。 展开更多
关键词 水热法 ZIF-8@TiO_(2) 光催化 罗丹明B
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ZIF-8改性自具微孔聚合物膜的制备及其对CO_(2)的分离性能
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作者 赵红永 赵晨阳 +1 位作者 丁晓莉 张永刚 《天津工业大学学报》 CAS 北大核心 2024年第4期1-6,共6页
为了提高自具微孔聚合物(PIMs)膜对CO_(2)的分离效果,对PIM-1膜进行功能化改性。首先,将PIM-1膜通过水解、置换等作用引入Zn2+离子,再将改性后的PIM-1膜浸泡在2-甲基咪唑的甲醇溶液中,于室温下在膜表面生长类沸石咪唑酯框架-8(ZIF-8)选... 为了提高自具微孔聚合物(PIMs)膜对CO_(2)的分离效果,对PIM-1膜进行功能化改性。首先,将PIM-1膜通过水解、置换等作用引入Zn2+离子,再将改性后的PIM-1膜浸泡在2-甲基咪唑的甲醇溶液中,于室温下在膜表面生长类沸石咪唑酯框架-8(ZIF-8)选择层,经过硅橡胶填补后得到无缺陷ZIF-8改性PIM-1膜(pZIF-8@PIM-1),并对其性能和结构进行测试和表征。结果表明:在离子改性后的PIM-1膜表面成功生长了厚度约0.8μm的ZIF-8选择层,晶体尺寸大小均匀,粒径直径在200 nm左右;与PIM-1纯膜相比,由于多价金属离子交联及ZIF-8选择层的存在,pZIF-8@PIM-1的CO_(2)扩散系数明显下降,CO_(2)/N_(2)扩散选择性有所上升,由0.89提升到1.01;ZIF-8中含氮有机杂环与CO_(2)之间的Lewis酸碱作用及2-甲基咪唑环上静电势对CO_(2)的亲和作用,使得pZIF-8@PIM-1的CO_(2)溶解度系数上升,且CO_(2)/N_(2)溶解选择性也得到提升,由18.56提升到20.31;改性后的PIM-1膜CO_(2)/N_(2)扩散选择性及CO_(2)/N_(2)溶解度选择性的双重提升共同促进了CO_(2)/N_(2)分离系数的提升,由原膜的16.57增加到20.43,具有良好的CO_(2)分离性能。 展开更多
关键词 气体分离膜 自具微孔聚合物 类沸石咪唑酯框架-8(ZIF-8) CO_(2)分离
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