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Expression analysis of the R2R3-MYB gene family in upland cotton and functional study of GhMYB3D5 in regulating Verticillium wilt resistance
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作者 jie liu Zhicheng Wang +15 位作者 Bin Chen Guoning Wang Huifeng Ke Jin Zhang Mengjia Jiao Yan Wang Meixia Xie Yanbin Li Dongmei Zhang Xingyi Wang Qishen Gu Zhengwen Sun Liqiang Wu Xingfen Wang Zhiying Ma Yan Zhang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第10期3294-3310,共17页
Improving plant resistance to Verticillium wilt(VW),which causes massive losses in Gossypium hirsutum,is a global challenge.Crop plants need to efficiently allocate their limited energy resources to maintain a balance... Improving plant resistance to Verticillium wilt(VW),which causes massive losses in Gossypium hirsutum,is a global challenge.Crop plants need to efficiently allocate their limited energy resources to maintain a balance between growth and defense.However,few transcriptional regulators specifically respond to Verticillium dahliae and the underlying mechanism has not been identified in cotton.In this study,we found that the that expression of most R2R3-MYB members in cotton is significantly changed by V.dahliae infection relative to the other MYB types.One novel R2R3-MYB transcription factor(TF)that specifically responds to V.dahliae,GhMYB3D5,was identified.GhMYB3D5 was not expressed in 15 cotton tissues under normal conditions,but it was dramatically induced by V.dahliae stress.We functionally characterized its positive role and underlying mechanism in VW resistance.Upon V.dahliae infection,the up-regulated GhMYB3D5 bound to the GhADH1 promoter and activated GhADH1expression.In addition,GhMYB3D5 physically interacted with GhADH1 and further enhanced the transcriptional activation of GhADH1.Consequently,the transcriptional regulatory module GhMYB3D5-GhADH1 then promoted lignin accumulation by improving the transcriptional levels of genes related to lignin biosynthesis(GhPAL,GhC4H,Gh4CL,and GhPOD/GhLAC)in cotton,thereby enhancing cotton VW resistance.Our results demonstrated that the GhMYB3D5 promotes defense-induced lignin accumulation,which can be regarded as an effective way to orchestrate plant immunity and growth. 展开更多
关键词 COTTON Verticillium wilt resistance GhMYB3D5 GhADH1 transcriptional regulatory module
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Failure mechanisms of AlGaN/GaN HEMTs irradiated by high-energy heavy ions with and without bias 被引量:1
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作者 Pei-Pei Hu Li-Jun Xu +9 位作者 Sheng-Xia Zhang Peng-Fei Zhai Ling Lv Xiao-Yu Yan Zong-Zhen Li Yan-Rong Cao Xue-Feng Zheng Jian Zeng Yuan He jie liu 《Nuclear Science and Techniques》 2025年第1期49-58,共10页
Gallium nitride(GaN)-based devices have significant potential for space applications.However,the mechanisms of radiation damage to the device,particularly from strong ionizing radiation,remains unknown.This study inve... Gallium nitride(GaN)-based devices have significant potential for space applications.However,the mechanisms of radiation damage to the device,particularly from strong ionizing radiation,remains unknown.This study investigates the effects of radiation on p-gate AlGaN/GaN high-electron-mobility transistors(HEMTs).Under a high voltage,the HEMT leakage current increased sharply and was accompanied by a rapid increase in power density that caused"thermal burnout"of the devices.In addition,a burnout signature appeared on the surface of the burned devices,proving that a single-event burnout effect occurred.Additionally,degradation,including an increase in the on-resistance and a decrease in the breakdown voltage,was observed in devices irradiated with high-energy heavy ions and without bias.The latent tracks induced by heavy ions penetrated the heterojunction interface and extended into the GaN layer.Moreover,a new type of N_(2)bubble defect was discovered inside the tracks using Fresnel analysis.The accumulation of N_(2)bubbles in the heterojunction and buffer layers is more likely to cause leakage and failure.This study indicates that electrical stress accelerates the failure rate and that improving heat dissipation is an effective reinforcement method for GaN-based devices. 展开更多
关键词 GaN HEMTs Heavy ions Single-event burnout Latent tracks Degradation
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Interplay between creeping fat and gut microbiota: A brand-new perspective on fecal microbiota transplantation in Crohn's disease
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作者 Ying Wang jie liu 《World Journal of Gastroenterology》 SCIE CAS 2025年第2期138-143,共6页
Inflammatory bowel disease,particularly Crohn's disease(CD),has been linked to modifications in mesenteric adipose tissue(MAT)and the phenomenon known as"creeping fat"(CrF).The presence of CrF is believe... Inflammatory bowel disease,particularly Crohn's disease(CD),has been linked to modifications in mesenteric adipose tissue(MAT)and the phenomenon known as"creeping fat"(CrF).The presence of CrF is believed to serve as a predictor for early clinical recurrence following surgical intervention in patients with CD.Notably,the incorporation of the mesentery during ileocolic resection for CD has been correlated with a decrease in surgical recurrence,indicating the significant role of MAT in the pathogenesis of CD.While numerous studies have indicated that dysbiosis of the gut microbiota is a critical factor in the development of CD,the functional implications of translocated microbiota within the MAT of CD patients remain ambiguous.This manuscript commentary discusses a recent basic research conducted by Wu et al.In their study,intestinal bacteria from individuals were transplanted into CD model mice,revealing that fecal microbiota trans-plantation(FMT)from healthy donors alleviated CD symptoms,whereas FMT from CD patients exacerbated these symptoms.Importantly,FMT was found to affect intestinal permeability,barrier function,and the levels of proinflammatory factors and adipokines.Collectively,these findings suggest that targeting MAT and CrF may hold therapeutic potential for patients with CD.However,the study did not evaluate the composition of the intestinal microbiota of the donors or the subsequent alterations in the gut microbiota.Overall,the gut microbiota plays a crucial role in the histopathology of CD,and thus,targeting MAT and CrF may represent a promising avenue for treatment in this patient population. 展开更多
关键词 Crohn's disease Mesenteric adipose tissue Creeping fat Fecal microbiota transplantation Gut microbiota
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An integrative approach clarifies species delimitation and biogeographic history of Debregeasia(Urticaceae)
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作者 Amos Kipkoech Ke Li +6 位作者 Richard I.Milne Oyetola Olusegun Oyebanji Moses C.Wambulwa Xiao-Gang Fu Dennis A.Wakhungu Zeng-Yuan Wu jie liu 《Plant Diversity》 2025年第2期229-243,共15页
Integrative data from plastid and nuclear loci are increasingly utilized to resolve species boundaries and phylogenetic relationships within major angiosperm clades.Debregeasia(Urticaceae),an economically important ge... Integrative data from plastid and nuclear loci are increasingly utilized to resolve species boundaries and phylogenetic relationships within major angiosperm clades.Debregeasia(Urticaceae),an economically important genus,presents challenges in species delimitation due to its overlapping morphological traits and unstable taxonomic assignments.Here,we analyzed 14 morphological traits and generated 12 data matrices from the plastomes and nrDNA using genome skimming from the nine recognized morphospecies to clarify species boundaries and assess barcode performance in Debregeasia.We also used a universal set of 353 nuclear genes to explore reticulate evolution and biogeographic history of Debregeasia.Plastomes of Debregeasia exhibited the typical quadripartite structure with conserved gene content and marginal independent variations in the SC/IR boundary at inter-and intra-specific levels.Three Debregeasia species were non-monophyletic and could not be discerned by any barcode;however,ultra-barcodes identified the remaining six(67%),outperforming standard barcodes(56%).Our phylogenetic analyses placed Debregeasia wallichiana outside the genus and suggested six monophyletic clades in Debregeasia,although the placement between Debregeasia hekouensis and Debregeasia libera varied.There was extensive trait overlap in key morphologically diagnostic characters,with reticulation analysis showing potentially pervasive hybridization,likely influenced by speciation patterns and overlaps between species ranges.We inferred that Debregeasia crown diversification began at ca.12.82 Ma(95%HPD:11.54-14.63 Ma)in the mid-Miocene within Australia,followed by vicariance and later longdistance dispersal,mainly out of southern China.Our findings highlight the utility of genomic data with integrative lines of evidence to refine species delimitation and explore evolutionary relationships in complex plant lineages. 展开更多
关键词 Debregeasia PLASTOME PHYLOGENOMICS Reticulate evolution Species delimitation Ultra-barcodes
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Numerical simulation for large baseline interferometric imaging altimeter
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作者 jie liu Bo liu +2 位作者 Xiaonan An Haifeng Kou Bing Li 《Geodesy and Geodynamics》 2025年第1期111-126,共16页
Sea topography information holds significant importance in oceanic research and the climate change detection.Radar imaging altimetry has emerged as the leading approach for global ocean observation,employing synthetic... Sea topography information holds significant importance in oceanic research and the climate change detection.Radar imaging altimetry has emerged as the leading approach for global ocean observation,employing synthetic aperture radar(SAR)interferometry to enhance the spatial resolution of Sea topography.Nevertheless,current payload capacity and satellite hardware limitations prevent the extension of the interferometric baseline by enlarging the physical antenna size.This constraint hinders achieving centimeter-level accuracy in interferometric altimetry.To address this challenge,we conducted a numerical simulation to assess the viability of a large baseline interferometric imaging altimeter(LB-IIA).By controlling the baseline within the range of 600-1000 m through spiral orbit design in two satellites and mitigating baseline de-correlation with the carrier frequency shift(CFS)technique,we aimed to overcome the above limitations.Our findings demonstrate the efficacy of the CFS technique in compensating for baseline decoherence,elevating coherence from less than 0.1 to over 0.85.Concurrently.The height difference accuracy between neighboring sea surfaces reaches 1 cm within a 1 km resolution.This study is anticipated to serve as a foundational reference for future interferometric imaging altimeter development,catering to the demand for high-precision sea topography data in accurate global bathymetry inversion. 展开更多
关键词 Sea topography Numerical simulation Carrier frequency shift(CFS) Large baseline interferometric imaging altimeter(LB-IIA)
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Integrated analysis reveals that miR-548ab promotes the development of obesity and T2DM
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作者 Chongge Pan Yali Hou +15 位作者 Yanting Hou Ruizhen Wang Meiyu Qian Xue Bai Maodi Liang Jingzhou Wang jie liu Qianqian Wei Ziyan Pan Ting Wang Chenyu Hu Kun Xiang Chun Yang Cuizhe Wang Hua Chen Jun Zhang 《Journal of Genetics and Genomics》 2025年第2期231-244,共14页
Dysregulation of microRNA(miRNA)expression following the development of obesity is closely linked to the onset of type 2 diabetes mellitus(T2DM).Identifying differentially expressed miRNAs and their roles in regulatin... Dysregulation of microRNA(miRNA)expression following the development of obesity is closely linked to the onset of type 2 diabetes mellitus(T2DM).Identifying differentially expressed miRNAs and their roles in regulating glucose metabolism will provide a theoretical foundation for the molecular mechanisms underlying obesity-induced T2DM.Here,we perform a genome-wide association study involving 5 glycolipid metabolism traits in 1783 Kazakh and 1198 Uyghur individuals to identify miRNAs associated with fasting plasma glucose(FPG)levels.A miR-548ab mimic and inhibitor are administered to hepatocytes and adipocytes,as well as obese and diabetic mice,to determine miR-548ab-related downstream signalling pathways.The effects of miR-548ab on glucose metabolism are validated using the glucose tolerance test and insulin tolerance test.Collectively,these results indicate that miR-548ab is significantly associated with FPG levels and obesity-related T2DM in both Kazakh and Uyghur populations.The miR-548ab-GULP1/SLC25A21-GLUT4 network exerts regulatory effects on glucose metabolism,obesity,and T2DM,positioning it as a candidate risk factor,potential diagnostic marker,and therapeutic target for obesity-induced T2DM.Additionally,through evolutionary analysis,the authentic variants or haplotypes of GULP1 and SLC25A21 are categorized according to their genetic susceptibility to T2DM.The miR-548ab inhibitor shows beneficial effects in obese and diabetic mice. 展开更多
关键词 OBESITY miR-548ab GULP1 and SLC25A21 Glucose metabolism T2DM
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Early esophageal cancer with mucosal bridging in the resting room: A case report
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作者 Ying-Ling liu jie liu Ye-Tao Wang 《World Journal of Gastrointestinal Endoscopy》 2025年第1期76-81,共6页
BACKGROUND Patients diagnosed with esophageal mucosal bridges often experience symptoms such as chest pain and dysphagia,which pose considerable challenges for endo-scopic surgical interventions.CASE SUMMARY We presen... BACKGROUND Patients diagnosed with esophageal mucosal bridges often experience symptoms such as chest pain and dysphagia,which pose considerable challenges for endo-scopic surgical interventions.CASE SUMMARY We present a case involving early-stage esophageal cancer discovered in a resting room,notable for the rare manifestation of esophageal mucosal bridging.Following a comprehensive multidisciplinary discussion and the development of a treatment strategy,we proceeded with endoscopic submucosal dissection for the patient.During the procedure,we encountered operational challenges due to the presence of a diverticulum and a partial absence of the muscularis propria.To facilitate the retraction of a portion of the resected specimen,we utilized dental floss.Ultimately,we successfully excised the entire lesion.After a three-day period of fasting with a water-only diet,subsequent iodine water cholan-giography did not indicate any perforations,and the patient was advised to transition to a liquid diet.The patient was discharged five days post-operation.A follow-up endoscopy conducted three months later revealed scar-like changes in the mid-esophagus,with the patient reporting no significant discomfort.CONCLUSION In summary,although esophageal mucosal bridges are rarely documented,they should be considered in the differential diagnosis of mechanical dysphagia.Furthermore,endoscopic therapy represents a feasible approach for their mana-gement. 展开更多
关键词 Esophageal cancer Endoscopic submucosal dissection Esophageal mucosal bridging ESOPHAGUS Case report
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Rapid report of source characteristics of 2025 M_(S)6.8 Dingri,Xizang earthquake sequence
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作者 Wen Yang jie liu +6 位作者 ZhiGao Yang Ran Cui JinRui Gao YanYan Han HuaiZhong Yu LingYuan Meng XueMei Zhang 《Earth and Planetary Physics》 2025年第2期467-473,共7页
Characteristics of the main shock and aftershocks of the Dingri M_(S)6.8 earthquake in the Xizang Autonomous region were determined by the double-difference location method using phase reports from Jan. 7 to Jan. 16, ... Characteristics of the main shock and aftershocks of the Dingri M_(S)6.8 earthquake in the Xizang Autonomous region were determined by the double-difference location method using phase reports from Jan. 7 to Jan. 16, 2025. We find that the aftershocks were generally distributed in a near NS direction along the Dengmoduo fault, with a long axis of about 70 km. There is an obvious seismic gap to the north side of the main shock, which is consistent with the location of the maximum rupture point as revealed by surface survey of the rupture and inversion analysis of the rupture process. In addition, the aftershock distribution exhibits obvious north-south segmentation characteristics. These observations suggest that the seismic fault of the main shock was likely to have been the Dengmoduo fault, which is NS and slightly inclined to the west. 展开更多
关键词 Dingri M_(S)6.8 earthquake Double-difference location aftershock activity Dengmoduo fault
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由4-羟基苯乙酮制备对乙酰氨基酚的两步合成实验设计
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作者 匡永清 刘劼 +3 位作者 冯见君 杨文 蔡双莲 史玲 《大学化学》 CAS 2024年第8期331-337,共7页
设计了由4-羟基苯乙酮制备对乙酰氨基酚的两步合成实验,并应用于本科教学。先由4-羟基苯乙酮与羟胺缩合产生4-羟基苯乙酮肟,再由三聚氯氰催化4-羟基苯乙酮的Beckmann重排反应得到对乙酰氨基酚。实验应用了回流、萃取、干燥、过滤、旋转... 设计了由4-羟基苯乙酮制备对乙酰氨基酚的两步合成实验,并应用于本科教学。先由4-羟基苯乙酮与羟胺缩合产生4-羟基苯乙酮肟,再由三聚氯氰催化4-羟基苯乙酮的Beckmann重排反应得到对乙酰氨基酚。实验应用了回流、萃取、干燥、过滤、旋转蒸发、薄层色谱和柱层析等重要有机实验操作,可综合训练学生的有机合成技术。通过制备具有重要医学和经济价值的目标化合物,向学生展示了有机合成技术在实际生活中的应用,有利于提高他们学习有机化学的兴趣。Beckmann重排采用了有机小分子催化剂,有助于学生加深理解有机催化的意义和Beckmann重排反应的机理。 展开更多
关键词 对乙酰氨基酚 酮肟化 BECKMANN重排 有机催化
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文有定法:探寻政府文书的写作逻辑
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作者 刘杰 任弢 陈念平 《公共行政评论》 CSSCI 北大核心 2024年第5期143-160,199,共19页
政府文书在中国政府运行中扮演着重要角色,但“政府文书究竟是如何生产的”这一基础性问题并未得到清晰回答。论文基于文书写作者视角,对文书写作者的经验笔谈进行分析,发现在政府文书生产过程中存在共性的支配逻辑。实践中的文书写作,... 政府文书在中国政府运行中扮演着重要角色,但“政府文书究竟是如何生产的”这一基础性问题并未得到清晰回答。论文基于文书写作者视角,对文书写作者的经验笔谈进行分析,发现在政府文书生产过程中存在共性的支配逻辑。实践中的文书写作,是引领方向和价值传递的政治过程,是发现问题、反映问题、解决问题的行政过程,也是组织内外沟通交流的语言应用过程。因此,以方向引领为导向的政治逻辑、以问题解决为导向的行政逻辑和以形式塑造为导向的语言逻辑共同支配着政府文书的写作过程。 展开更多
关键词 政府文书 文书写作 写作逻辑
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布鲁顿酪氨酸激酶抑制剂介导的出血机制及临床管理
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作者 宋丽霞 康虹阳 +3 位作者 韩国将 刘洁 范凌(综述) 佟长青(审校) 《中国肿瘤临床》 CAS CSCD 北大核心 2024年第14期737-741,共5页
布鲁顿酪氨酸激酶(Bruton's tyrosine kinase,BTK)抑制剂是治疗B细胞淋巴瘤的新型靶向药物,尤其在套细胞淋巴瘤(mantle cell lymphoma,MCL)、慢性淋巴细胞白血病/小淋巴细胞淋巴瘤(chronic lymphocytic leukemia/small lymphocytic ... 布鲁顿酪氨酸激酶(Bruton's tyrosine kinase,BTK)抑制剂是治疗B细胞淋巴瘤的新型靶向药物,尤其在套细胞淋巴瘤(mantle cell lymphoma,MCL)、慢性淋巴细胞白血病/小淋巴细胞淋巴瘤(chronic lymphocytic leukemia/small lymphocytic lymphoma,CLL/SLL)、华氏巨球蛋白血症(Waldenstr?m's macroglobulinaemia,WM)的治疗中显示出良好的疗效。随着BTK抑制剂在临床上的广泛使用,出血的不良反应逐渐显现。出血事件是由于BTK抑制剂的脱靶效应引起,在使用过程中通过多条信号通路来影响血小板功能,导致出血的发生。出血一旦发生将影响患者的治疗,严重会危机生命,应该加强出血的临床管理,本文就BTK抑制剂引起出血的作用机制及临床管理进行综述。 展开更多
关键词 BTK抑制剂 出血 不良事件 临床管理
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Argatroban promotes recovery of spinal cord injury by inhibiting the PAR1/JAK2/STAT3 signaling pathway 被引量:3
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作者 Chenxi Zhao Tiangang Zhou +9 位作者 Ming Li jie liu Xiaoqing Zhao Yilin Pang Xinjie liu Jiawei Zhang Lei Ma Wenxiang Li Xue Yao Shiqing Feng 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第2期434-439,共6页
Argatroban is a synthetic thrombin inhibitor approved by U.S.Food and Drug Administration for the treatment of thrombosis.However,whether it plays a role in the repair of spinal cord injury is unknown.In this study,we... Argatroban is a synthetic thrombin inhibitor approved by U.S.Food and Drug Administration for the treatment of thrombosis.However,whether it plays a role in the repair of spinal cord injury is unknown.In this study,we established a rat model of T10 moderate spinal cord injury using an NYU Impactor ModerⅢand performed intraperitoneal injection of argatroban for 3 consecutive days.Our results showed that argatroban effectively promoted neurological function recovery after spinal cord injury and decreased thrombin expression and activity in the local injured spinal cord.RNA sequencing transcriptomic analysis revealed that the differentially expressed genes in the argatroban-treated group were enriched in the JAK2/STAT3 pathway,which is involved in astrogliosis and glial scar formation.Western blotting and immunofluorescence results showed that argatroban downregulated the expression of the thrombin receptor PAR1 in the injured spinal cord and the JAK2/STAT3 signal pathway.Argatroban also inhibited the activation and proliferation of astrocytes and reduced glial scar formation in the spinal cord.Taken together,these findings suggest that argatroban may inhibit astrogliosis by inhibiting the thrombin-mediated PAR1/JAK2/STAT3 signal pathway,thereby promoting the recovery of neurological function after spinal cord injury. 展开更多
关键词 ARGATROBAN ASTROGLIOSIS JAK/STAT signaling pathway protease-activated receptor-1 spinal cord injury THROMBIN vimentin
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Rapid report of source parameters of 2023 M6.2 Jishishan,Gansu earthquake sequence 被引量:3
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作者 ZhiGao Yang jie liu +2 位作者 YingYing Zhang Wen Yang XueMei Zhang 《Earth and Planetary Physics》 EI CAS CSCD 2024年第2期436-443,共8页
The M6.2 earthquake in Jishishan,Gansu Province,on December 18,2023,caused extraordinary earthquake disasters.It was located in the northern part of the north−south seismic zone,which is a key area for earthquake moni... The M6.2 earthquake in Jishishan,Gansu Province,on December 18,2023,caused extraordinary earthquake disasters.It was located in the northern part of the north−south seismic zone,which is a key area for earthquake monitoring in China.The newly built dense strong motion stations in this area provide unprecedented conditions for high-precision earthquake relocation,especially the earthquake focal depth.This paper uses the newly built strong motion and traditional broadband seismic networks to relocate the source locations of the M3.0 and above aftershocks and to invert their focal mechanisms.The horizontal error of earthquake location is estimated to be 0.5−1 km,and the vertical error is 1−2 km.The focal depth range of aftershocks is 9.6−14.6 km,distributed in a 12-km-long strip with SSE direction.Aftershocks in the south are more concentrated horizontally and vertically,while aftershocks in the north are more scattered.The focal mechanisms of the main shock and aftershocks are relatively consistent,and the P-axis orientation is consistent with the regional strain direction.There is a seismic blank area of M3.0 and above,about 3−5 km between the main shock and aftershocks.It is suggested that the energy released by the main shock rupture is concentrated in this area.Based on the earthquake location and focal mechanism of the main shock,it is inferred that the Northern Lajishan fault zone is the seismogenic structure of the main shock,and the main shock did not occur on the main fault,but on a secondary fault.The initial rupture depth and centroid depth of the main shock were 12.8 and 14.0 km,respectively.The source rupture depth may not be the main reason for the severe earthquake disaster. 展开更多
关键词 Jishishan earthquake earthquake relocation focal mechanism strong motion data
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Elastic-viscoplastic behaviors of polymer-blend geocell sheets:Numerical and experimental investigations 被引量:1
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作者 Yang Zhao Jianbin Chen +7 位作者 Zheng Lu jie liu Abdollah Tabaroei Chuxuan Tang Yong Wang Lipeng Wu Bo Wang Hailin Yao 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第10期4261-4271,共11页
Polymer-blend geocell sheets(PBGS)have been developed as substitute materials for manufacturing geocells.Various attempts have been made to test and predict the behaviors of commonly used geogrids,geotextiles,geomembr... Polymer-blend geocell sheets(PBGS)have been developed as substitute materials for manufacturing geocells.Various attempts have been made to test and predict the behaviors of commonly used geogrids,geotextiles,geomembranes,and geocells.However,the elastic-viscoplastic behaviors of novel-developed geocell sheets are still poorly understood.Therefore,this paper investigates the elastic-viscoplastic behaviors of PBGS to gain a comprehensive understanding of their mechanical properties.Furthermore,the tensile load-strain history under various loading conditions is simulated by numerical calculation for widespread utilization.To achieve this goal,monotonic loading tests,short-term creep and stress relaxation tests,and multi-load-path tests(also known as arbitrary loading history tests)are performed using a universal testing machine.The results are simulated using the nonlinear three-component(NLTC)model,which consists of three nonlinear components,i.e.a hypo-elastic component,a nonlinear inviscid component,and a nonlinear viscid component.The experimental and numerical results demonstrate that PBGS exhibit significant elastic-viscoplastic behavior that can be accurately predicted by the NLTC model.Moreover,the tensile strain rates significantly influence the tensile load,with higher strain rates resulting in increased tensile loads and more linear load-strain curves.Also,parametric analysis of the rheological characteristics reveals that the initial tensile strain rates have negligible impact on the results.The rate-sensitivity coefficient of PBGS is approximately 0.163,which falls within the typical range observed in most geosynthetics. 展开更多
关键词 Polymer-blend geocell sheets Geosynthetics Elastic-viscoplastic behavior Numerical simulations Tensile load-strain response
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Subsurface multi-physical characterization of mountain excavation and city construction in loess plateau with a fiber-optic sensing system 被引量:1
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作者 jie liu Bin Shi +3 位作者 Kai Gu Meng-Ya Sun Jun-Cheng Yao He-Ming Han 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第8期2935-2946,共12页
Mountain excavation and city construction(MECC)projects being launched in the Loess Plateau in China involve the creation of large-scale artificial land.Understanding the subsurface evolution characteristics of the ar... Mountain excavation and city construction(MECC)projects being launched in the Loess Plateau in China involve the creation of large-scale artificial land.Understanding the subsurface evolution characteristics of the artificial land is essential,yet challenging.Here,we use an improved fiber-optic monitoring system for its subsurface multi-physical characterization.The system enables us to gather spatiotemporal distribution of various parameters,including strata deformation,temperature,and moisture.Yan’an New District was selected as a case study to conduct refined in-situ monitoring through a 77 m-deep borehole and a 30 m-long trench.Findings reveal that the ground settlement involves both the deformation of the filling loess and the underlying intact loess.Notably,the filling loess exhibits a stronger creep capability compared to underlying intact loess.The deformation along the profile is unevenly distributed,with a positive correlation with soil moisture.Water accumulation has been observed at the interface between the filling loess and the underlying intact loess,leading to a significant deformation.Moreover,the temperature and moisture in the filling loess have reached a new equilibrium state,with their depths influenced by atmospheric conditions measuring at 31 m and 26 m,respectively.The refined investigation allows us to identify critical layers that matter the sustainable development of newly created urban areas,and provide improved insights into the evolution mechanisms of land creation. 展开更多
关键词 Mountain excavation and city construction Fiber-optic monitoring Multi-physical characterization Compacted loess
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Coherent optical frequency transfer via 972-km fiber link 被引量:1
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作者 邓雪 张翔 +8 位作者 臧琦 焦东东 王丹 刘杰 高静 许冠军 董瑞芳 刘涛 张首刚 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期277-282,共6页
We demonstrate coherent optical frequency dissemination over a distance of 972 km by cascading two spans where the phase noise is passively compensated for.Instead of employing a phase discriminator and a phase lockin... We demonstrate coherent optical frequency dissemination over a distance of 972 km by cascading two spans where the phase noise is passively compensated for.Instead of employing a phase discriminator and a phase locking loop in the conventional active phase control scheme,the passive phase noise cancellation is realized by feeding double-trip beat-note frequency to the driver of the acoustic optical modulator at the local site.This passive scheme exhibits fine robustness and reliability,making it suitable for long-distance and noisy fiber links.An optical regeneration station is used in the link for signal amplification and cascaded transmission.The phase noise cancellation and transfer instability of the 972-km link is investigated,and transfer instability of 1.1×10^(-19)at 10^(4)s is achieved.This work provides a promising method for realizing optical frequency distribution over thousands of kilometers by using fiber links. 展开更多
关键词 optical frequency transfer fiber link phase noise cancellation
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团结就是力量,独立才能发光——关于AIE和ACQ效应的科普实验
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作者 贾艳媛 荣融 +3 位作者 刘洁 郭晶 姜国玉 郭硕 《大学化学》 CAS 2024年第9期349-358,共10页
发光材料在生活中具有诸多的应用,但目前面向公众的有关发光材料尤其是ACQ和AIE分子的发光现象及其光学性能研究的普及实验仍有欠缺。本实验是以科普为目的,分别针对各个年龄段的受众设计了特色性普及实验;同时,本实验也是一个多场景适... 发光材料在生活中具有诸多的应用,但目前面向公众的有关发光材料尤其是ACQ和AIE分子的发光现象及其光学性能研究的普及实验仍有欠缺。本实验是以科普为目的,分别针对各个年龄段的受众设计了特色性普及实验;同时,本实验也是一个多场景适用性科普实验,分别于线上线下多渠道进行展示。实验步骤简单易行,色彩丰富,发光效果明显。既便于操作,又能极大地让公众了解生活中的发光分子,更重要的是本实验可以有效引导青少年发现、提出并解决科学问题,更有利于实现对青少年一定程度上的研究性思维与方法的培养,具有一定创新性。 展开更多
关键词 发光材料 ACQ效应 AIE效应 荧光 梯度科普
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CD155、TIGIT在胃肠神经内分泌肿瘤中的表达及与临床病理特征的关系
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作者 谢伟 余松 +7 位作者 侯能易 严力 曹钦兴 旦真甲 袁兴梅 陆河江 刘杰 庞明辉 《世界华人消化杂志》 CAS 2024年第2期123-133,共11页
背景胃肠神经内分泌肿瘤(gastrointestinal neuroendocrine neoplasms,GI-NENs)临床表现多样,部分具有高侵袭性及转移性,预后差.收集我院诊治的GI-NENs患者的临床病理资料,免疫组化检测CD155、T细胞免疫球蛋白和ITIM结构域蛋白(T cell i... 背景胃肠神经内分泌肿瘤(gastrointestinal neuroendocrine neoplasms,GI-NENs)临床表现多样,部分具有高侵袭性及转移性,预后差.收集我院诊治的GI-NENs患者的临床病理资料,免疫组化检测CD155、T细胞免疫球蛋白和ITIM结构域蛋白(T cell immunoreceptor with Ig and ITIM domains,TIGIT)的表达量,探讨其与临床病理和预后的关系,为患者的治疗提供一个新的方向.目的探讨CD155、TIGIT在GI-NENs中的表达量与临床病理特征的关系.方法收集2016-11/2020-08经我院诊治的168例GI-NENs患者的临床病理资料.免疫组化检测CD155、TIGIT的表达量,探讨其与临床病理和预后的关系.结果CD155和TIGIT在病理分级高的GI-NENs组织中,表达量也较高,差异有统计学意义(P<0.05);CD155表达量与年龄、肿瘤位置、肿瘤最大直径、病理分级、T分期、淋巴结转移、远处转移、TNM分期、Ki-67指数有关(P<0.05);TIGIT表达量与肿瘤最大直径、病理分级、T分期、淋巴结转移、TNM分期、Ki-67指数有关(P<0.05);CD155和TIGIT表达量高的患者预后较表达量低者差,差异有统计学意义(P<0.05).结论CD155和TIGIT表达量在不同分级、分期的GI-NENs患者存在差异,可能参与了GI-NENs的发生及进展的调控过程,高表达可能提示预后不佳. 展开更多
关键词 胃肠神经内分泌肿瘤 CD155 TIGIT 预后
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基于精准气象条件下供暖热负荷调控研究进展
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作者 刘洁 柳伊 邹大伟 《气候变化研究快报》 2024年第6期1682-1687,共6页
节能是推进碳达峰、碳中和、促进高质量发展的重要支撑,供热节能是全球面临的重要难题,实现及时准确的热负荷预测是实现供热系统节能的基础。在影响热网负荷发生变化的众多因素当中,室外温度、太阳辐射、风速和相对湿度等气象因素的影... 节能是推进碳达峰、碳中和、促进高质量发展的重要支撑,供热节能是全球面临的重要难题,实现及时准确的热负荷预测是实现供热系统节能的基础。在影响热网负荷发生变化的众多因素当中,室外温度、太阳辐射、风速和相对湿度等气象因素的影响最为显著。文章阐述了近年来我国精细化气象预报技术的发展历程,回顾了气象要素与供暖热负荷相关性研究进展。我国多元化、网格化、精细化的气象预报发展,为按需供热及供热精细化调控提供了有利条件。同时随着研究手段的进步,回归分析和机器学习等基于数据支撑下的负荷预测方法被广泛应用,且在负荷预测中表现出了较高的精度,为多气象参数的负荷预测奠定了良好的基础。研究分析认为随着我国综合气象观测系统、多源实况融合分析技术和多尺度数值模式的快速发展,能够建立基于综合气象参数的气候补偿调控模型,有利于提高按需供热精细化调控水平。 展开更多
关键词 供热节能 气象预报 热负荷预测
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Ti6Al4V细长梁结构件加工变形理论分析
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作者 刘通 刘杰 +2 位作者 刘启蒙 蒋俊香 崔博 《新疆钢铁》 2024年第4期59-61,共3页
文章针对Ti6Al4V细长梁零件的加工变形问题,采用欧拉-伯努利梁理论分析了典型支撑方式对细长梁的整体静刚度以及加工变形的影响,为Ti6Al4V细长梁结构类零件的装夹方案设计及加工工艺提供了理论指导和技术支撑。
关键词 细长梁结构件 TI6AL4V 加工变形
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