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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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微种植体支抗用于骨性错牙合畸形患者的疗效及对血清MMP-8、MMP-9、NO、IGF-1水平的影响
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作者 赵欢欢 孙洋 曹素敏 《临床和实验医学杂志》 2024年第20期2211-2215,共5页
目的观察微种植体支抗用于骨性错牙合畸形患者的疗效及对血清基质金属蛋白酶8(MMP-8)、基质金属蛋白酶9(MMP-9)、一氧化氮(NO)、胰岛素样生长因子-1(IGF-1)水平的影响。方法前瞻性选取2022年2月至2023年12月在沧州市中心医院进行诊治的... 目的观察微种植体支抗用于骨性错牙合畸形患者的疗效及对血清基质金属蛋白酶8(MMP-8)、基质金属蛋白酶9(MMP-9)、一氧化氮(NO)、胰岛素样生长因子-1(IGF-1)水平的影响。方法前瞻性选取2022年2月至2023年12月在沧州市中心医院进行诊治的骨性错牙合畸形患者84例作为研究对象,按照随机数字表法将其分为观察组(n=42)和对照组(n=42)。观察组采用微种植体支抗治疗,对照组采用口外弓支抗治疗,统计两组治疗前和治疗6个月后的口腔结构、上下颌骨角度[上齿槽座角(SNA)、下齿槽座角(SNB)、上齿槽座点及鼻根点与下齿槽座点形成角(ANB)]、血清MMP-8、MMP-9、NO、IGF-1水平,记录两组美学满意度及并发症发生情况。结果在口腔结构方面,观察组磨牙移位为(3.21±0.84)mm,显著低于对照组[(5.32±1.11)mm],上中切牙凸距差、中切牙倾角差分别为(4.24±1.66)mm、(26.42±4.38)°,均显著高于对照组[(2.45±1.21)mm、(12.44±3.05)°],差异均有统计学意义(P<0.05)。治疗6个月后,观察组SNA、ANB分别为(72.01±2.19)°、(4.68±0.78)°,显著低于对照组[(76.49±2.21)°、(5.37±0.82)°],SNB为(78.65±2.36)°,显著高于对照组[(76.07±2.44)°],差异均有统计学意义(P<0.05)。治疗6个月后,观察组血清MMP-8、MMP-9、NO、IGF-1水平分别为(94.16±10.84)μmol/L、(74.49±9.87)pg/mL、(55.72±8.03)μmol/L、(643.85±26.32)ng/mL,显著低于对照组[(112.51±11.02)μmol/L、(86.52±10.01)pg/mL、(67.96±8.41)μmol/L、(703.36±26.96)ng/mL],差异均有统计学意义(P<0.05)。在美学满意度方面,观察组总满意度为92.86%,明显高于对照组(76.19%),差异有统计学意义(P<0.05)。在并发症方面,观察组总发生率为9.52%,明显低于对照组(30.95%),差异有统计学意义(P<0.05)。结论微种植体支抗治疗骨性错牙合畸形疗效较好,可以有效改善患者口腔结构和上下颌骨角度,调节血清MMP-8、MMP-9、NO、IGF-1水平,且美学满意度高,并发症少,值得临床推广应用。 展开更多
关键词 骨性错牙合畸形 微种植体支抗 口外弓支抗 基质金属蛋白酶8 基质金属蛋白酶9 一氧化氮 胰岛素样生长因子-1
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Sn掺杂ZIF-8衍生ZnO纳米材料的制备及其NO_(2)传感性能
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作者 第五华婷 葛万银 +4 位作者 赵虎 黎茜 杨茂浩 尚世帆 罗梓力 《陕西科技大学学报》 北大核心 2024年第5期126-133,共8页
具有高灵敏度、低检测限的半导体气体传感器不仅在环境监测中具有重要意义,而且在痕量气体检测中也具有潜在的应用.在本研究中,我们采用溶液法及固相烧结等方法相结合成功地合成Sn掺杂ZIF-8衍生的ZnO纳米材料,使用X射线衍射仪(XRD)、扫... 具有高灵敏度、低检测限的半导体气体传感器不仅在环境监测中具有重要意义,而且在痕量气体检测中也具有潜在的应用.在本研究中,我们采用溶液法及固相烧结等方法相结合成功地合成Sn掺杂ZIF-8衍生的ZnO纳米材料,使用X射线衍射仪(XRD)、扫描电子显微镜(SEM)及傅里叶变化红外光谱分析仪(FT-IR)表征了材料的物相、形貌结构及官能团.本研究制备的ZnO:Sn传感器在180℃下对200 ppm的NO_(2)具有超高的响应(2495)、快速的响应/恢复时间(52/9 s)和低的检测限(0.5 ppb)等出色的气敏性能.ZnO:Sn传感器优异的气敏性能主要归因于ZIF-8衍生的ZnO所具有的多孔结构、大的比表面积及Sn掺杂引起的电子敏化作用.Sn掺杂能显著提高ZnO对NO_(2)的气敏性能,有望应用于低浓度NO_(2)高灵敏性的检测与传感. 展开更多
关键词 ZIF-8 气体传感 no_(2)检测 多孔结构
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8-Hydroxy-2'-Deoxyguanosine (8-OH-2dG) as a Biomarker of Oxidative Stress (OS) in the Acute Exacerbation of Spontaneous Preterm Birth (SPTB)
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作者 Salma Abdi Mahmoud 《Open Journal of Obstetrics and Gynecology》 2024年第10期1548-1555,共8页
Spontaneous preterm birth (SPTB) is characterized by the delivery of a baby before 37 completed weeks of gestation, and this condition is associated with significant health challenges for the newborn. Emerging evidenc... Spontaneous preterm birth (SPTB) is characterized by the delivery of a baby before 37 completed weeks of gestation, and this condition is associated with significant health challenges for the newborn. Emerging evidence highlights the importance of biomarkers for understanding the mechanisms underlying SPTB. One such biomarker, 8-OH-2dG, plays a critical role in evaluating oxidative stress and its impact on pregnancy outcomes. It has been demonstrated that 8-OH-2dG is a product of oxidative DNA damage and is widely recognized as a key indicator of cellular oxidative stress. Elevated reactive oxygen species in SPTB result in higher levels of the DNA degradation product 8-OH-2dG in amniotic fluid, causing damage to maternal and fetal tissues that could lead to premature rupture of fetal membranes. Therefore, evaluating the role of 8-OH-2dG in SPTB is of great interest. This review provides an overview of the current knowledge on 8-OH-2dG as a biomarker for SPTB and aims to elucidate its mechanism in this condition. 展开更多
关键词 Preterm Birth 8-Hydroxy-2'-Deoxyguanosine Oxidative Stress DNA Damage
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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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Unknown Environment Measurement Mapping by Unmanned Aerial Vehicle Using Kalman Filter-Based Low-Cost Estimated Parallel 8-Beam LIDAR
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作者 Mohamed Rabik Mohamed Ismail Muthuramalingam Thangaraj +2 位作者 Khaja Moiduddin Zeyad Almutairi Mustufa Haider Abidi 《Computers, Materials & Continua》 SCIE EI 2024年第9期4263-4279,共17页
The measurement and mapping of objects in the outer environment have traditionally been conducted using ground-based monitoring systems,as well as satellites.More recently,unmanned aerial vehicles have also been emplo... The measurement and mapping of objects in the outer environment have traditionally been conducted using ground-based monitoring systems,as well as satellites.More recently,unmanned aerial vehicles have also been employed for this purpose.The accurate detection and mapping of a target such as buildings,trees,and terrains are of utmost importance in various applications of unmanned aerial vehicles(UAVs),including search and rescue operations,object transportation,object detection,inspection tasks,and mapping activities.However,the rapid measurement and mapping of the object are not currently achievable due to factors such as the object’s size,the intricate nature of the sites,and the complexity of mapping algorithms.The present system introduces a costeffective solution for measurement and mapping by utilizing a small unmanned aerial vehicle(UAV)equipped with an 8-beam Light Detection and Ranging(LiDAR)system.This approach offers advantages over traditional methods that rely on expensive cameras and complex algorithm-based approaches.The reflective properties of laser beams have also been investigated.The system provides prompt results in comparison to traditional camerabased surveillance,with minimal latency and the need for complex algorithms.The Kalman estimation method demonstrates improved performance in the presence of noise.The measurement and mapping of external objects have been successfully conducted at varying distances,utilizing different resolutions. 展开更多
关键词 8 beam LiDAR UAV MEASUREMENT MAPPING Kalman filter
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Complex shell Fe-ZnO derived from ZIF-8 as high-quality acetone MEMS sensor
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作者 Bing Shen Tongwei Yuan +2 位作者 Wenshuang Zhang Yang Chen Jiaqiang Xu 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第11期577-581,共5页
Zeolitic imidazolate frameworks(ZIFs)are a series of materials composited by metal ions and organic ligands with high specific surface area,which might be great precursors to produce metal oxides by calcination for ga... Zeolitic imidazolate frameworks(ZIFs)are a series of materials composited by metal ions and organic ligands with high specific surface area,which might be great precursors to produce metal oxides by calcination for gas sensor application.However,Zn-ZIF(ZIF-8)is hard to transform as ZnO in air and keeping the unique framework simultaneously.In this work,Fe^(2+)was introduced into the metal node to replace a part of Zn^(2+)ions,and it could be oxidized as Fe^(3+)in the calcination to facilitate the oxidation process of the 2-methylimdazole ligands to give Fe-ZnO complex shell with high specific surface area(108 m~2/g)and abundant oxygen vacancies(48%).The micro electro mechanical systems(MEMS)sensor based on the6%-Fe-ZnO complex shell performed outstanding gas sensing properties to the low-concentration acetone vapor,including high response(ΔR/R_g=11.2 to 5 ppm acetone),superior selectivity(S_(acetone)/S_(ethanol)=5.6)and fast response speed(τ_(res)=2.6 s).This work not only provided the research of an exceptional acetone MEMS sensor,but also induced a strategy to produce metal oxide derived from ZIFs with complex structures for the universal synthesis methodology. 展开更多
关键词 ZIF-8 Zno Ion oxidation MEMS sensor Acetone sensor
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Phenotypic Image Recognition of Asparagus Stem Blight Based on Improved YOLOv8
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作者 Shunshun Ji Jiajun Sun Chao Zhang 《Computers, Materials & Continua》 SCIE EI 2024年第9期4017-4029,共13页
Asparagus stem blight,also known as“asparagus cancer”,is a serious plant disease with a regional distribution.The widespread occurrence of the disease has had a negative impact on the yield and quality of asparagus ... Asparagus stem blight,also known as“asparagus cancer”,is a serious plant disease with a regional distribution.The widespread occurrence of the disease has had a negative impact on the yield and quality of asparagus and has become one of the main problems threatening asparagus production.To improve the ability to accurately identify and localize phenotypic lesions of stem blight in asparagus and to enhance the accuracy of the test,a YOLOv8-CBAM detection algorithm for asparagus stem blight based on YOLOv8 was proposed.The algorithm aims to achieve rapid detection of phenotypic images of asparagus stem blight and to provide effective assistance in the control of asparagus stem blight.To enhance the model’s capacity to capture subtle lesion features,the Convolutional Block AttentionModule(CBAM)is added after C2f in the head.Simultaneously,the original CIoU loss function in YOLOv8 was replaced with the Focal-EIoU loss function,ensuring that the updated loss function emphasizes higher-quality bounding boxes.The YOLOv8-CBAM algorithm can effectively detect asparagus stem blight phenotypic images with a mean average precision(mAP)of 95.51%,which is 0.22%,14.99%,1.77%,and 5.71%higher than the YOLOv5,YOLOv7,YOLOv8,and Mask R-CNN models,respectively.This greatly enhances the efficiency of asparagus growers in identifying asparagus stem blight,aids in improving the prevention and control of asparagus stem blight,and is crucial for the application of computer vision in agriculture. 展开更多
关键词 YOLOv8 asparagus stem blight image recognition PEST
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Amino acid deletions at positions 893 and 894 of cytotoxinassociated gene A protein affect Helicobacter pylori gastric epithelial cell interactions
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作者 Zhi-Jing Xue Ya-Nan Gong +6 位作者 Li-Hua He Lu Sun Yuan-Hai You Dong-Jie Fan Mao-Jun Zhang Xiao-Mei Yan Jian-Zhong Zhang 《World Journal of Gastroenterology》 SCIE CAS 2024年第41期4449-4460,共12页
BACKGROUND Helicobacter pylori(H.pylori)persistently colonizes the human gastric mucosa in more than 50%of the global population,leading to various gastroduodenal diseases ranging from chronic gastritis to gastric car... BACKGROUND Helicobacter pylori(H.pylori)persistently colonizes the human gastric mucosa in more than 50%of the global population,leading to various gastroduodenal diseases ranging from chronic gastritis to gastric carcinoma.Cytotoxin-associated gene A(CagA)protein,an important oncoprotein,has highly polymorphic Glu-Pro-Ile-Tyr-Ala segments at the carboxyl terminus,which play crucial roles in pathogenesis.Our previous study revealed a significant association between amino acid deletions at positions 893 and 894 and gastric cancer.AIM To investigate the impact of amino acid deletions at positions 893 and 894 on CagA function.METHODS We selected a representative HZT strain from a gastric cancer patient with amino acid deletions at positions 893 and 894.The cagA gene was amplified and mutated into cagA-NT and cagA-NE(sequence characteristics of strains from nongastric cancer patients),cloned and inserted into pAdtrack-CMV,and then transfected into AGS cells.The expression of cagA and its mutants was examined using realtime polymerase chain reaction and Western blotting,cell elongation via cell counting,F-actin cytoskeleton visualization using fluorescence staining,and interleukin-8(IL-8)secretion via enzyme-linked immunosorbent assay.RESULTS The results revealed that pAdtrack/cagA induced a more pronounced hummingbird phenotype than pAdtrack/cagA-NT and pAdtrack/cagA-NE(40.88±3.10 vs 32.50±3.17,P<0.001 and 40.88±3.10 vs 32.17±3.00,P<0.001)at 12 hours after transfection.At 24 hours,pAdtrack/cagA-NE induced significantly fewer hummingbird phenotypes than pAdtrack/cagA and pAdtrack/cagA-NT(46.02±2.12 vs 53.90±2.10,P<0.001 and 46.02±2.12 vs 51.15±3.74,P<0.001).The total amount of F-actin caused by pAdtrack/cagA was significantly lower than that caused by pAdtrack/cagA-NT and pAdtrack/cagA-NE(27.54±17.37 vs 41.51±11.90,P<0.001 and 27.54±17.37 vs 41.39±14.22,P<0.001)at 12 hours after transfection.Additionally,pAdtrack/cagA induced higher IL-8 secretion than pAdtrack/cagA-NT and pAdtrack/cagA-NE at different times after transfection.CONCLUSION Amino acid deletions at positions 893 and 894 enhance CagA pathogenicity,which is crucial for revealing the pathogenic mechanism of CagA and identifying biomarkers of highly pathogenic H.pylori. 展开更多
关键词 Cytotoxin-associated gene A Glu-Pro-Ile-Tyr-Ala Hummingbird phenotype INTERLEUKIN-8 Helicobacter pylori
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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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Tumor-derived DEFB1 induces immune tolerance by inhibiting maturation of dendritic cell and impairing CD8+T cell function in esophageal squamous cell carcinoma
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作者 Jingjing Duan Haotian Wang +10 位作者 Minglu Liu Yin Chen Ning Li Jieqiong Liu Lingxiong Wang Lin Li Yaru Liu Pengfei Dong Xiuxuan Wang Zhongyi Fan Shunchang Jiao 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2024年第4期351-367,共17页
Objective:CD8+T cells are the key effector cells in the anti-tumor immune response.The mechanism underlying the infiltration of CD8+T cells in esophageal squamous cell carcinoma(ESCC)has not been clearly elucidated.Me... Objective:CD8+T cells are the key effector cells in the anti-tumor immune response.The mechanism underlying the infiltration of CD8+T cells in esophageal squamous cell carcinoma(ESCC)has not been clearly elucidated.Methods:Fresh ESCC tissues were collected and grouped according to the infiltration density of CD8+T cells.After the transcriptome sequencing on these samples and the combined analyses with The Cancer Genome Atlas(TCGA)ESCC data,a secreted protein DEFB1 was selected to explore its potential role in the infiltration of CD8+T cells.Bioinformatics analyses,histological verification and in vitro experiments were then performed.Results:DEFB1 was highly expressed in ESCC,and the high expression of DEFB1 was an independent risk factor for overall survival.Since the up-regulation or down-regulation of DEFB1 did not affect the proliferation,migration and apoptosis of ESCC cells,we speculated that the oncogenic effect of DEFB1 was achieved by regulating microenvironmental characteristics.Bioinformatics analyses suggested that DEFB1 might play a major role in the inflammatory response and anti-tumor immune response,and correlate to the infiltration of immature dendritic cell(imDC)in ESCC.Histological analyses further confirmed that there were less CD8+T cells infiltrated,less CD83+mature DC(mDC)infiltrated and more CD1a+imDC infiltrated in those ESCC samples with high expression of DEFB1.After the treatment with recombinant DEFB1 protein,the maturation of DC was hindered significantly,followed by the impairment of the killing effects of T cells in both 2D and 3D culture in vitro.Conclusions:Tumor-derived DEFB1 can inhibit the maturation of DC and weaken the function of CD8+T cells,accounting for the immune tolerance in ESCC.The role of DEFB1 in ESCC deserves further exploration. 展开更多
关键词 CD8+T cells DEFB1 dendritic cells esophageal squamous cell carcinoma tumor immune microenvironment
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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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