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Chiral multiple-resonance thermally activated delayed fluorescence materials based on chiral spiro-axis skeleton for efficient circularly polarized electroluminescence

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Science China Chemistry 2024年第7期67卷 2257-2264页

作者： Shi-Quan Song Xiao Han Zhong-Zhong Huo Ching-Fai Yip xian-fang hong Meng-Ning Ding You-Xuan Zheng State Key Laboratory of Coordination Chemistry Jiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China Key Laboratory of Mesoscopic Chemistry of Ministry of Education School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China

Chiral luminescence materials have potential applications in the field of three-dimensional displays due to their circularly polarized luminescence(CPL)***,the further development of circularly polarized organic light-emitting diodes(CP-OLEDs)needs to meet the requirements of high efficiency,high color purity,low cost,and high dissymmetry factor(gPLor gEL),chiral multiple resonance thermally activated delayed fluorescence(MR-TADF)materials are considered as candidates in these ***,based on a pair of chiral spirofluorene precursors,two pairs of high-performance chiral MR-TADF emitters((R/S)-p-Spiro-DtBuCzB and(R/S)-m-Spiro-DtBuCzB)are developed,which exhibit strong emissions peaking at 491 and 502 nm in toluene with full-width at half-maximum values of 25 and 33 nm,*** addition,small singlet–triplet energy gaps of 0.15 and 0.10 eV with high absolute photoluminescence efficiencies of 95.0%and 96.7%are observed for p-Spiro-DtBuCzB and m-Spiro-DtBuCzB molecules,*** based on p-Spiro-DtBuCzB and m-Spiro-DtBuCzB display high maximum external quantum efficiencies of 29.6%and 33.8%,*** importantly,CP-OLEDs present symmetric circularly polarized electroluminescence spectra with|gEL|factors of 3.36×10^(-4)and 7.66×10^(-4)for devices based on(R/S)-p-Spiro-DtBuCzB and(R/S)-m-Spiro-DtBuCzB enantiomers,respectively.

关键词： chiral spiro-axis skeleton-based material multiple resonance thermally activated delayed fluorescence circularly polarized electroluminescence dissymmetry factor external quantum efficiency

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狭缝引导配体13′UTR通过miR-34a-5p/SIRT1轴调节内皮细胞表型

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中国生物化学与分子生物学报 2024年第3期40卷 362-372页

作者：欧涛胡志琴高原伍华燕陈凯茵徐金东方咸宏单志新华南理工大学医学院广州510006 广州医科大学附属第五医院药学部广州510799 南方医科大学附属广东省人民医院(广东省医学科学院)医学研究部广州510080 南方医科大学附属广东省人民医院(广东省医学科学院)麻醉科广州510080 南方医科大学附属广东省人民医院(广东省医学科学院)心内科广州510080

在高等生物的进化过程中,mRNA的3′非翻译区(3′untranslated region,3′UTR)序列显著增加,提示3′UTR在生物功能调节中可能发挥重要作用。我们发现狭缝引导配体1(slit guidance ligand 1,SLIT1)3′UTR在肥厚型心肌病(HCM)患者心肌中水... 详细信息

在高等生物的进化过程中,mRNA的3′非翻译区(3′untranslated region,3′UTR)序列显著增加,提示3′UTR在生物功能调节中可能发挥重要作用。我们发现狭缝引导配体1(slit guidance ligand 1,SLIT1)3′UTR在肥厚型心肌病(HCM)患者心肌中水平降低,但其对肥厚心肌中血管功能调节的作用机制不清楚。利用腺病毒介导在主动脉内皮细胞(human aortic endothelial cells,HAECs)中过表达SLIT13′UTR,检测HAECs中一氧化氮合酶(endothelial nitric oxide synthases,eNOS)和血管内皮生长因子A(vascular endothelial growth factor,VEGFA)表达。分别采用划痕实验和基于Matrigel胶的管腔形成实验检测HAECs的迁移和成管腔能力。结果发现,过表达SLIT13′UTR会升高HAECs中p-eNOS、eNOS和VEGFA水平(P<0.01),并促进HAECs迁移和成管腔能力(P<0.01)。生物信息学预测提示,SLIT13′UTR上有多个微RNA(miRNA)的潜在结合位点,反义RNA纯化技术(RNA antisense purification,RAP)筛选和利用Ago2抗体进行RNA结合蛋白质免疫沉淀(RNA binding protein immunoprecipitation,RIP)结果显示,SLIT13′UTR与miR-34a-5p存在结合作用,而过表达SLIT13′UTR的HAECs中miR-34a-5p水平显著降低(P<0.05)。Western印迹结果证实,miR-34a-5p可逆转过表达SLIT13′UTR对去乙酰化酶SIRT1的上调作用(P<0.05)。在HAECs中转染miR-34a-5p和si-SIRT1,可一致地抑制过表达SLIT13′UTR引起的p-eNOS、eNOS和VEGFA增加(P<0.05,P<0.01),及促进HAECs迁移和成管腔的能力(P<0.01,P<0.001)。因此,SLIT13′UTR可以特异性吸附miR-34a-5p,通过miR-34a-5p/SIRT1轴发挥促进内皮细胞迁移和管腔生成的作用。

关键词：狭缝引导配体1,3′非翻译区血管内皮细胞微RNA

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Advance in reversible Zn anodes promoted by 2D materials

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Rare Metals 2024年第4期43卷 1350-1369页

作者： Shu-Yuan Lei Jin-Xiu Feng Yu-Chao Chen Dong Zheng Wen-xian Liu Wen-Hui Shi fang-fang Wu Xie-hong Cao School of Materials Science and Engineering Zhejiang University of TechnologyHangzhou310014China Center for Membrane Separation and Water Science and Technology College of Chemical EngineeringZhejiang University of TechnologyHangzhou310014China

With the growing energy demand associated with high safety and low-cost requirement,aqueous zinc-ion batteries(AZIBs)have been considered as one of the most promising next-generation ***,some key issues,such as uncontrollable dendrites growth,severe corrosion,hydrogen evolution and side reactions of Zn anodes during charge/discharge process,have hindered its pragmatic ***-dimensional(2D)materials hold advantages of unique physical and chemical properties,large surface areas and abundant active sites,which have been successfully used to overcome the above shortcomings of Zn anodes in recent *** this review,the issues and challenges of Zn anodes are ***,the state-of-the-art progress on Zn anodes modification based on 2D materials such as graphene,2D metal carbides and nitrides(MXenes),2D metal-organic frameworks(MOFs),2D covalent organic frameworks(COFs),2D transition metal compounds and other 2D materials is discussed in ***,the perspectives of employing 2D materials in highly reversible Zn anodes are summarized and discussed.

关键词： 2D materials Aqueous zinc-ion battery Zn anodes Dendrites growth

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Efficacy and safety of minimally invasive laparoscopic surgery under general anesthesia for ovarian cancer

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World Journal of Clinical Cases 2024年第9期12卷 1569-1577页

作者： xian Qin Chen Chen Yang Liu xian-hong Hua Jia-Yi Li Meng-Jie Liang fang Wu Department of Anesthesiology The First People's Hospital of Jiangxia DistrictWuhan 430200Hubei ProvinceChina Department of Obstetrics and Gynecology The First People's Hospital of Jiangxia DistrictWuhan 430200Hubei ProvinceChina

BACKGROUND Ovarian cancer is one of the most common malignant tumors in female reproductive system in the world,and the choice of its treatment is very important for the survival rate and prognosis of *** open surgery is the main treatment for ovarian cancer,but it has the disadvantages of big trauma and slow *** the continuous development of minimally invasive technology,minimally invasive laparoscopic surgery under general anesthesia has been gradually applied to the treatment of ovarian cancer because of its advantages of less trauma and quick ***,the efficacy and safety of minimally invasive laparoscopic surgery under general anesthesia in the treatment of ovarian cancer are still *** To explore the efficacy and safety of general anesthesia minimally invasive surgery in the treatment of ovarian *** The clinical data of 90 patients with early ovarian cancer in our hospital were analyzed *** to the different surgical treatment methods,patients were divided into study group and control group(45 cases in each group).The study group received minimally invasive laparoscopic surgery under general anesthesia for ovarian cancer,while the control group received traditional open surgery for ovarian *** European Organization for Research and Treatment of Cancer Quality of Life Questionnaire(EORTC QLQ-C30),clinical efficacy and safety of the two groups were *** The intraoperative blood loss,length of hospital stay,postoperative gas evacuation time,and postoperative EORTC QLQ-C30 score of the study group were significantly better than those of the control group(P<0.05).The incidence of postoperative complications in the study group was significantly lower than in the control group(P<0.05).The two groups had no significant differences in the preoperative adrenocorticotropic hormone(ACTH),androstenedione(AD),cortisol(Cor),cluster of differentiation 3 positive(CD3+),and clu

关键词： Early-stage ovarian cancer Efficacy Minimally invasive Laparoscopy Safety Surgery

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Endoscopic-ultrasound-guided biliary drainage with placement of electrocautery-enhanced lumen-apposing metal stent for palliation of malignant biliary obstruction:Updated meta-analysis

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World Journal of Gastrointestinal Surgery 2024年第3期16卷 907-920页

作者： Zu-xiang Peng fang-fang Chen Wen Tang Xu Zeng hong-Juan Du Ru-xian Pi hong-Ming Liu Xiao-Xiao Lu Department of Hepatobiliary Surgery Daping HospitalArmy Medical UniversityChongqing 400042China Department of Oncology Chongqing General HospitalChongqing UniversityChongqing 401147China Department of Gastroenterology and Hepatobiliary Surgery People’s Hospital of Fenggang CountyGuizhou 564200Guizhou ProvinceChina Hepatobiliary and Pancreatic Tumor Center Chongqing University Cancer HospitalChongqing 400030China

BACKGROUND Endoscopic ultrasound-guided biliary drainage using electrocautery-enhanced(ECE)delivery of lumen-apposing metal stent(LAMS)is gradually being re-cognized as a viable palliative technique for malignant biliary obstruction after endoscopic retrograde cholangiopancreatography(ERCP)***,most of the studies that have assessed its efficacy and safety were small and *** meta-analyses of six or fewer studies that were published 2 years ago were therefore underpowered to yield convincing *** To update the efficacy and safety of ECE-LAMS for treatment of biliary ob-struction after ERCP *** We searched PubMed,EMBASE,and Scopus databases from the inception of the ECE technique to May 13,*** outcome measure was pooled technical success rate,and secondary outcomes were pooled rates of clinical success,re-intervention,and adverse ***-analysis was performed using a random-effects model following Freeman-Tukey double-arcsine transformation in R soft-ware(version 4.1.3).RESULTS Fourteen eligible studies involving 620 participants were ultimately *** pooled rate of technical success was 96.7%,and clinical success was 91.0%.Adverse events were reported in 17.5%of *** reinter-vention rate was 7.3%.Subgroup analyses showed results were generally *** ECE-LAMS has favorable success with acceptable adverse events in relieving biliary obstruction when ERCP is *** consistency of results across most subgroups suggested that this is a generalizable approach.

关键词： Biliary obstruction Biliary drainage Electrocautery-enhanced lumen-apposing metal stents Endoscopic ultrasound Endoscopic retrograde cholangiopancreatography failure

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Basic Survey Scheduling for the Wide Field Survey Telescope(WFST)

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Research in Astronomy and Astrophysics 2024年第1期24卷 59-69页

作者： Yan-Peng Chen Ji-An Jiang Wen-Tao Luo xian-Zhong Zheng Min fang Chao Yang Yuan-Yu hong Zong-Fei Lü Purple Mountain Observatory Chinese Academy of SciencesNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China Department of Astronomy University of Science and Technology of ChinaHefei 230026China National Astronomical Observatory of Japan National Institutes of Natural Sciences2-21-1 OsawaMitakaTokyo 181-8588Japan Institute of Deep Space Sciences Deep Space Exploration LaboratoryHefei 230026China

Aiming at improving the survey efficiency of the Wide Field Survey Telescope, we have developed a basic scheduling strategy that takes into account the telescope characteristics, observing conditions, and weather conditions at the Lenghu site. The sky area is divided into rectangular regions, referred to as “tiles,” with a size of2°. 577 × 2°. 634 slightly smaller than the focal area of the mosaic CCDs. These tiles are continuously filled in annulars parallel to the equator. The brightness of the sky background, which varies with the moon phase and distance from the moon, plays a significant role in determining the accessible survey fields. Approximately 50connected tiles are grouped into one block for observation. To optimize the survey schedule, we perform simulations by taking into account the length of exposures, data readout, telescope slewing, and all relevant observing conditions. We utilize the Greedy Algorithm for scheduling optimization. Additionally, we propose a dedicated dithering pattern to cover the gaps between CCDs and the four corners of the mosaic CCD array, which are located outside of the 3° field of view. This dithering pattern helps to achieve relatively uniform exposure maps for the final survey outputs.

关键词： telescopes surveys Moon

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Left atrial enlargement and non-paroxysmal atrial fibrillation as risk factors for left atrial thrombus/spontaneous Echo contrast in patients with atrial fibrillation and low CHA2DS2-VASc score

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Journal of Geriatric Cardiology 2020年第3期17卷 155-159页

作者： Wei-Dong LIN Yu-Mei XUE fang-Zhou LIU xian-hong fang xian-Zhang ZHAN hong-Tao LIAO Gary Tse Shu-Lin WU Guangdong Cardiovascular Institute Guangdong General HospitalGuangzhouChina Department of Medicine and Therapeutics Faculty of MedicineChinese University of Hong KongHong KongChina Li Ka Shing Institute of Health Sciences Faculty of MedicineChinese University of Hong KongHong KongChina

Objective To determine the risk factors for thromboembolism in lower risk patients with non-valvular atrial fibrillation(AF)and low CHA2DS2-VASc scores,which remain *** We retrospectively analyzed the baseline clinical characteristics,routine laboratory parameters,and echocardiographic measurements of 705 patients(71.1%male;mean age:52.10±9.64 years)with low CHA2DS2-VASc score(0 or 1;1 point for female sex)out of 1346 consecutive patients with non-valvular AF who underwent transesophageal echocardiography(TEE)at Guangdong Cardiovascular Institute between January 2013 and December *** Patients with left atrial thrombus(LAT)or spontaneous echo contrast(SEC)on TEE(24/705,4%)showed a higher incidence rate of vascular disease(54.2%vs.32.9%,P=0.045)and non-paroxysmal AF(79.2%vs.29.4%,P<0.001),larger left atrial diameter(43.08±4.59 vs.36.02±5.53 mm,P<0.001),and lower left ventricular ejection fraction(58.23±8.82%vs.64.15±7.14%,P<0.001)than those *** logistic regression analysis identified left atrial diameter[odds ratio(OR)=1.171,95%confidence interval(CI):1.084–1.265,P<0.001]and non-paroxysmal AF(OR=3.766,95%CI:1.282–11.061,P=0.016)as independent risk factors for LAT/*** ROC curve analysis,a left atrial dimeter cutoff of 37.5 mm yielded 95.0%sensitivity and 62.7%specificity(AUC:0.847,P<0.0001,95%CI:0.793–0.914).Conclusion In patients with non-valvular AF with low CHA2DS2-VASc score,the presence of LAT or SEC was associated with left atrial enlargement,which had moderate predictive value,and non-paroxysmal AF.

关键词： Atrial fibrillation Left atrial diameter Left atrial spontaneous echo contrast Left atrial thrombus

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Enhanced hydrogen evolution performance by 3D ordered macroporous Ru-CoP@NC electrocatalysts

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Rare Metals 2024年第3期43卷 1095-1107页

作者： Chen-Chen Zhang Sheng Wei Li-xian Sun Yi-fang Ouyang Fen Xu Hai-Liang Chu hong-GePan Li-Xin Chen Xue-Zhang Xiao School of Material Science and Engineering Guilin University of Electronic TechnologyGuilin541004China School of Chemistry and Chemical Engineering Guangxi UniversityNanning530004China Shenzhen Institute of Advanced Technology Chinese Academy of SciencesShenzhen518055GuangdongChina Institute of Science and Technology for New Energy Xi'an Technological UniversityXi'an710021China School of Materials Science and Engineering Zhejiang UniversityHangzhou310058China

Electrocatalytic water splitting coupled with sustainable energies is identified as an environmentally friendly and renewable strategy to generate high-quality hydrogen for the fuel ***,the main challenge is to develop high performance,low cost and chemically stable electrocatalysts to decline the energy barriers and enhance the sluggish kinetics of hydrogen evolution reaction(HER).Herein,a three-dimensional hierarchically ordered macroporous Ru-CoP@NC electrocatalyst(3DOM Ru-CoP@NC)derived from ordered macro-microporous metal-organic frameworks has been prepared using the precursor@template and double-solvent *** prepared 3DOM Ru-CoP@NC catalyst exhibits an overpotential of 15 mV(j=10 mA·cm^(-2))and a reaction Tafel slope of 38 mV·dec^(-1)in alkaline electrolyte,which are superior to commercial Pt@C ***,the overpotential and reaction Tafel slope of this catalyst in acidic media are 45 mV and 50 mV·dec^(-1),*** outstanding HER activities of 3DOM Ru-CoP@NC catalysts are ascribed to the 3D highly interconnectedreticular nanospaces that can increase effective reaction active *** N dope d carbon framework improves the electronic properties and ***,the strong interaction of Ru and CoP nanoparticles also boosts the HER *** results indicate that 3DOM Ru-CoP@NC catalysts with high catalytic activities have a broad application prospect in the future.

关键词： Hydrogen evolution reaction Template method 3D ordered macroporous Ru-CoP@NC

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Predictive value of serum uric acid on left atrial spontaneous echo contrast in non-valvular atrial fibrillation patients

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Journal of Geriatric Cardiology 2015年第6期12卷 641-646页

作者： hong-Tao LIAO fang-Zhou LIU Yu-Mei XUE xian-Zhang ZHAN xian-hong fang Jun HUANG Wei WEI fang RAO Hai DENG Yang LIU Wei-Dong LIN Shu-Lin WU Department of Cardiovascular Guangdong Cardiovascular Institute Guangdong General Hospital Guangdong Academy of Medical Science GuangzhouGuangdong China Research Center of Medical Science Guangdong General Hospital Guangdong Academy of Medical Science Guangzhou Guangdong China

ObjectivesTo 调查在浆液之间的关系尿酸( SUA )和左 atrial 在纤维性颤动( AF ) *** 回顾地屏蔽了的非瓣膜的 atrial 的自发的回响对比(LA秒)在 radiofrequency 以前经历了 transesophageal echocardiography 的有 AF 的 1,476 个连... 详细信息

ObjectivesTo 调查在浆液之间的关系尿酸( SUA )和左 atrial 在纤维性颤动( AF ) *** 回顾地屏蔽了的非瓣膜的 atrial 的自发的回响对比(LA秒)在 radiofrequency 以前经历了 transesophageal echocardiography 的有 AF 的 1,476 个连续就医的病人导管脱离，在广东医院将军的左 atrial 附器闭合和电的 cardioversion 。所有病人的临床的基线特征上的数据与左 atrial 血栓从电子医药记录和病人的 *** 排除被收集， 1,354 个病人进入了现在的学习， 57 是 LA 秒。吝啬的女 SUA 水平(380.88 ±；94.35 µ； mol/L 对 323.37 ±；72.19 µ； mol/L， P <；0.001 ) 并且男 SUA 水平(416.97 ±；98.87 µ； mol/L 对 367.88 ±；68.50 µ； mol/L， P = 0.008 ) 比在控制在有 LA 秒的病人更高显著地是两个。吝啬的左 atrial 尺寸(41.32 ±；5.12 公里对 36.12 ±；5.66 公里， P <；0.001 ) 在有 LA 秒的病人是显著地更大的。在 multivariate 回归分析， SUA 水平是为 LA 秒的一个独立风险因素(或：1.008， P <；0.001 ) 。在操作典型曲线分析的接收装置，在为在女性和男性预言 LA 秒的 SUA 的曲线下面的相应区域分别地是 0.670 和 0.657。SUA 水平在有 *** 的非瓣膜的 AF 病人是显著地更高的水平是一个独立风险因素并且在南部的中国在非瓣膜的 AF 病人之中为 LA 秒有中等预兆的价值。

关键词：患者心房预测价值颤动尿酸超声心动图膜

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A disk I/O optimized system for concurrent graph processing jobs

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Frontiers of Computer Science 2024年第3期18卷 13-29页

作者： xianghao XU fang WANG hong JIANG Yongli CHENG Dan FENG Peng fang School of Computer Science and Engineering Nanjing University of Science and TechnologyNanjing 210094China Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430074China Department of Computer Science&Engineering University of Texas at ArlingtonArlingtonTX 76019USA College of Computer and Data Science Fuzhou UniversityFuzhou 350108China Zhejiang Lab Hangzhou 311121China

In order to analyze and process the large graphs with high cost efficiency,researchers have developed a number of out-of-core graph processing systems in recent years based on just one commodity *** the other hand,with the rapidly growing need of analyzing graphs in the real-world,graph processing systems have to efficiently handle massive concurrent graph processing(CGP)***,due to the inherent design for single graph processing job,existing out-of-core graph processing systems usually incur unnecessary data accesses and severe competition of I/O bandwidth when handling the CGP *** this paper,we propose GraphCP,a disk I/O optimized out-of-core graph processing system that efficiently supports the processing of CGP *** proposes a benefit-aware sharing execution model to share the I/O access and processing of graph data among the CGP jobs and adaptively schedule the graph data loading based on the states of vertices,which efficiently overcomes above challenges faced by existing out-of-core graph processing ***,GraphCP adopts a dependency-based future-vertex updating model so as to reduce disk I/Os in the future *** addition,GraphCP organizes the graph data with a Source-Sorted Sub-Block graph representation for better processing capacity and I/O access *** evaluation results show that GraphCP is 20.5×and 8.9×faster than two out-of-core graph processing systems GridGraph and GraphZ,and 3.5×and 1.7×faster than two state-of-art concurrent graph processing systems Seraph and GraphSO.

关键词： graph processing disk I/O concurrent jobs

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