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A step to the decentralized real-time timekeeping network
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作者 王芳敏 陈雨锋 +4 位作者 周建华 蔺玉亭 杨军 王波 王力军 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期183-191,共9页
The composite time scale(CTS) provides an accurate and stable time-frequency reference for modern science and technology. Conventional CTS always features a centralized network topology, which means that the CTS is ac... The composite time scale(CTS) provides an accurate and stable time-frequency reference for modern science and technology. Conventional CTS always features a centralized network topology, which means that the CTS is accompanied by a local master clock. This largely restricts the stability and reliability of the CTS. We simulate the restriction and analyze the influence of the master clock on the CTS. It proves that the CTS's long-term stability is also positively related to that of the master clock, until the region dominated by the frequency drift of the H-maser(averaging time longer than ~10~5s).Aiming at this restriction, a real-time clock network is utilized. Based on the network, a real-time CTS referenced by a stable remote master clock is achieved. The experiment comparing two real-time CTSs referenced by a local and a remote master clock respectively reveals that under open-loop steering, the stability of the CTS is improved by referencing to a remote and more stable master clock instead of a local and less stable master clock. In this way, with the help of the proposed scheme, the CTS can be referenced to the most stable master clock within the network in real time, no matter whether it is local or remote, making democratic polycentric timekeeping possible. 展开更多
关键词 frequency synchronization network composite time scale frequency stability democratic timekeeping
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Acupuncture for cervical dystonia associated with anxiety and depression: A case report
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作者 Ya-Ting Zhang Jin-Jing Zhang +4 位作者 Bi-Xiang Zha Yin-Qiu Fan Yuan-Bo Xu jun yang Qing-Ping Zhang 《World Journal of Clinical Cases》 SCIE 2024年第1期204-209,共6页
BACKGROUND Cervical dystonia(CD)is a type of muscle tone disorder that usually occurs in the neck muscles.Due to the intermittent or continuous involuntary contraction of the neck muscles,the head and neck are twisted... BACKGROUND Cervical dystonia(CD)is a type of muscle tone disorder that usually occurs in the neck muscles.Due to the intermittent or continuous involuntary contraction of the neck muscles,the head and neck are twisted and skewed and some postural abnormalities occur.Long-term abnormal posture or pain can cause negative emotions in patients,which can affect their quality of life.CASE SUMMARY This case report included a 37-year-old woman who was diagnosed with CD associated with anxiety and depression;the accompanying symptoms were head and neck tilt of approximately 90°to the right and mental abnormality.After two courses of acupuncture treatment,the patient’s head and neck can be maintained in a normal position,and the negative emotions can be relieved.CONCLUSION This case indicates that acupuncture can effectively improve CD and the emotional state and quality of life of patients,making it an effective alternative treatment for the condition. 展开更多
关键词 Cervical dystonia Anxiety and depression Neurological disease ACUPUNCTURE Case report
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Identification and validation of a pyroptosis-related prognostic model for colorectal cancer based on bulk and single-cell RNA sequencing data
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作者 Li-Hua Zhu jun yang +3 位作者 Yun-Fei Zhang Li Yan Wan-Rong Lin Wei-Qing Liu 《World Journal of Clinical Oncology》 2024年第2期329-355,共27页
BACKGROUND Pyroptosis impacts the development of malignant tumors,yet its role in colorectal cancer(CRC)prognosis remains uncertain.AIM To assess the prognostic significance of pyroptosis-related genes and their assoc... BACKGROUND Pyroptosis impacts the development of malignant tumors,yet its role in colorectal cancer(CRC)prognosis remains uncertain.AIM To assess the prognostic significance of pyroptosis-related genes and their association with CRC immune infiltration.METHODS Gene expression data were obtained from The Cancer Genome Atlas(TCGA)and single-cell RNA sequencing dataset GSE178341 from the Gene Expression Omnibus(GEO).Pyroptosis-related gene expression in cell clusters was analyzed,and enrichment analysis was conducted.A pyroptosis-related risk model was developed using the LASSO regression algorithm,with prediction accuracy assessed through K-M and receiver operating characteristic analyses.A nomo-gram predicting survival was created,and the correlation between the risk model and immune infiltration was analyzed using CIBERSORTx calculations.Finally,the differential expression of the 8 prognostic genes between CRC and normal samples was verified by analyzing TCGA-COADREAD data from the UCSC database.RESULTS An effective pyroptosis-related risk model was constructed using 8 genes-CHMP2B,SDHB,BST2,UBE2D2,GJA1,AIM2,PDCD6IP,and SEZ6L2(P<0.05).Seven of these genes exhibited differential expression between CRC and normal samples based on TCGA database analysis(P<0.05).Patients with higher risk scores demonstrated increased death risk and reduced overall survival(P<0.05).Significant differences in immune infiltration were observed between low-and high-risk groups,correlating with pyroptosis-related gene expression.CONCLUSION We developed a pyroptosis-related prognostic model for CRC,affirming its correlation with immune infiltration.This model may prove useful for CRC prognostic evaluation. 展开更多
关键词 Colorectal cancer PYROPTOSIS Single-cell RNA sequencing Immune infiltration Prognostic model
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Up-Regulation of the Gap Junction Intercellular Communication by Tea Polyphenol in the Human Metastatie Lung Carcinoma Cell Line 被引量:3
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作者 Xiangyong Li Qinghua Wang +6 位作者 jun yang Yanjuan Pan Qingyong Chen Xiqing Yan Daxin Wang Xijian Zhou Yuquan Wu 《Journal of Cancer Therapy》 2012年第1期64-70,共7页
Our previous study has proven that tea polyphenol has a role in lung neoplasms. The present communication was to investage the anti-proliferation effect of tea polyphenol on the PG cells, which was a high metastatic h... Our previous study has proven that tea polyphenol has a role in lung neoplasms. The present communication was to investage the anti-proliferation effect of tea polyphenol on the PG cells, which was a high metastatic human lung carcinoma cell line, by 3-(4,5)-dimethylthiahiazo(-z-y1)-3,5-diphenytetrazoliumromide (MTT) cell viability assay, and to study the change of intracellular calcium concentration, connexin43 (Cx43) expression, gap junctional intercellular communication (GJIC) and cell cycle distribution after the tea polyphenol treatment by laser scanning confocal microscopy and flow cytometry. The results showed that 1) tea polyphenol could kill the PG cells in a dose-depent manner via inhibiting the PG cell proliferation and blocking the PG cell cycle progression staying in G0/G1 phase and not transfering in S and G2/M phases to reduce the PG cell proliferation index;2) the increases of intracellular calcium concentration, GJIC and Cx43 expression were related with the tea polyphenol doses. The data suggested that tea polyphenol could inhibit the growth of PG cells, which mechanism was associated with the up-regulation of GJIC. 展开更多
关键词 Tea POLYPHENOL LUNG Neoplasms Highly METASTATIC HUMAN LUNG Carcinoma Cell Line Gap Junction INTERCELLULAR Communication
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Three-dimensional velocity structure around the focal area of the 2021 MS6.4 Yangbi earthquake 被引量:1
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作者 Yunpeng Zhang Weitao Wang +4 位作者 Wei yang Min Liu Jinbo Su Xiaobin Li jun yang 《Earthquake Science》 2021年第5期399-412,共14页
On May 21,2021,an MS6.4 earthquake occurred in Yangbi,Yunnan province,China,which exhibited typical foreshock-mainshock-aftershock characteristics.To better understand the velocity structure of the focal area and adja... On May 21,2021,an MS6.4 earthquake occurred in Yangbi,Yunnan province,China,which exhibited typical foreshock-mainshock-aftershock characteristics.To better understand the velocity structure of the focal area and adjacent fault zones,Pg/Sg travel times at 12 seismic stations for the local earthquakes with ML≥1.5 from 2009-2019 and the Yangbi sequence in May of 2021 were used to invert the three-dimensional(3D)structures for both vP and v_(P)/v_(S).The obtained structure extends deeply to 15 km for area(25°N-26.5°N,99.5°E-101°E)at a horizontal resolution of 10×10 km,and the accuracy of the v_(P) velocity was verified using airgun signals excited by the Binchuan Airgun Transmitting Seismic Station(BATSS).The resulting v_(P) and v^(P)/v_(S) images correlate with existing fault zones and the Yangbi sequence,including:(1)The shallow velocity structure at 0 km agrees with local topography,where the Binchuan basin exhibits low-v_(P) and high-v_(P)/v_(S) values.From 3-15 km,v_(P) and v_(P)/v_(S) show variations,and the boundaries are consistent with the main faults(e.g.,the Weixi-Qiaohou-Weishan,Honghe,and Chenghai faults).(2)The largest foreshock(M_(S)5.6),main-shock(MS6.4),and largest aftershock(M_(S)5.2)occurred near the boundaries where both vP and v_(P)/v_(S) have clear contrasts.(3)Small earthquakes are also concentrated in the transition zone between high-and low-vP and v_(P)/v_(S) anomalies,and are biased toward low-v_(P)/v_(S) zones.(4)Boundaries in v_(P) and v_(P)/v_(S) are observed at 20 km west of the Weixi-Qiaohou-Weishan fault,indicating that there may exist one hidden fault. 展开更多
关键词 MS6.4 Yangbi earthquake Honghe fault Weixi-Qiaohou-Weishan fault body wave tomography air-gun source.
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A real-time AI-assisted seismic monitoring system based on new nodal stations with 4G telemetry and its application in the Yangbi M_(S) 6.4 aftershock monitoring in southwest China 被引量:1
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作者 junlun Li Huajian Yao +10 位作者 Baoshan Wang yang yang Xin Hu Lishu Zhang Beng Ye jun yang Xiaobin Li Feng Liu Guoyi Chen Chang Guo Wen yang 《Earthquake Research Advances》 CSCD 2022年第2期3-10,共8页
A rapidly deployable dense seismic monitoring system which is capable of transmitting acquired data in real time and analyzing data automatically is crucial in seismic hazard mitigation after a major earthquake.Howeve... A rapidly deployable dense seismic monitoring system which is capable of transmitting acquired data in real time and analyzing data automatically is crucial in seismic hazard mitigation after a major earthquake.However,it is rather difficult for current seismic nodal stations to transmit data in real time for an extended period of time,and it usually takes a great amount of time to process the acquired data manually.To monitor earthquakes in real time flexibly,we develop a mobile integrated seismic monitoring system consisting of newly developed nodal units with 4G telemetry and a real-time AI-assisted automatic data processing workflow.The integrated system is convenient for deployment and has been successfully applied in monitoring the aftershocks of the Yangbi M_(S) 6.4 earthquake occurred on May 21,2021 in Yangbi County,Dali,Yunnan in southwest China.The acquired seismic data are transmitted almost in real time through the 4G cellular network,and then processed automat-ically for event detection,positioning,magnitude calculation and source mechanism inversion.From tens of seconds to a couple of minutes at most,the final seismic attributes can be presented remotely to the end users through the integrated system.From May 27 to June 17,the real-time system has detected and located 7905 aftershocks in the Yangbi area before the internal batteries exhausted,far more than the catalog provided by China Earthquake Networks Center using the regional permanent stations.The initial application of this inte-grated real-time monitoring system is promising,and we anticipate the advent of a new era for Real-time Intelligent Array Seismology(RIAS),for better monitoring and understanding the subsurface dynamic pro-cesses caused by Earth's internal forces as well as anthropogenic activities. 展开更多
关键词 Seismic dense array 4G data transmission Real-time earthquake monitoring Machine-learning assisted processing Real-time intelligent array seismology
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A sutureless subconjunctival M-shaped limbus incision for hard cataracts 被引量:1
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作者 Ping-Hong Lai jun yang +1 位作者 Fang Hang Tlili Zaafouri 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2016年第11期1694-1696,共3页
Dear Editor,Iam Dr.Ping-Hong Lai,from the Jiangxi Eye Center,Jiangxi Provincial People's Hospital,Nanchang,Jiangxi Province,China.I would like to present the technique of subconjunctival M-shaped limbus incision f... Dear Editor,Iam Dr.Ping-Hong Lai,from the Jiangxi Eye Center,Jiangxi Provincial People's Hospital,Nanchang,Jiangxi Province,China.I would like to present the technique of subconjunctival M-shaped limbus incision for a series of cases with hard cataracts. 展开更多
关键词 Figure A sutureless subconjunctival M-shaped limbus incision for hard cataracts
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创新驱动创业的微观触发机制:基于决断的理论模型
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作者 杨俊 金敖 叶文平 《管理学季刊》 2023年第4期70-83,166,共15页
创新驱动创业是把握并凝练创业时代特征的新兴构念。Zahra(2023)从创业研究领域发展角度进一步拓展并丰富了创新驱动创业的理论内涵和未来研究方向。本文沿着这一思路,进一步聚焦不确定性这一关键属性,聚焦创新驱动创业的微观触发机制... 创新驱动创业是把握并凝练创业时代特征的新兴构念。Zahra(2023)从创业研究领域发展角度进一步拓展并丰富了创新驱动创业的理论内涵和未来研究方向。本文沿着这一思路,进一步聚焦不确定性这一关键属性,聚焦创新驱动创业的微观触发机制开展延伸理论探讨,并结合中国情境特征提出了研究展望和建议,以期推动和丰富针对这一主题的国内相关研究进展。 展开更多
关键词 创新驱动创业 不确定性 创业决断
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An accessible seismological dataset of 2021 Yangbi M_(S)6.4 earthquake
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作者 Shuguang Wang Hui yang +12 位作者 Weilai Wang Fang Wang Zheng Liu Wei yang Weitao Wang Yunpeng Zhang Lu Li Jiupeng Hu Xiaobin Li Wenjian Cha Beng Ye Hongbo Zhu jun yang 《Earthquake Science》 2021年第5期460-464,共5页
A M_(S)6.4 earthquake occurred on 21 May 2021 in Yangbi county,Dali prefecture,Yunnan,China,at 21:48 Beijing Time(13:48 UTC).Earthquakes with an M3.0 or higher occurred before and after the main shock.Seismic data ana... A M_(S)6.4 earthquake occurred on 21 May 2021 in Yangbi county,Dali prefecture,Yunnan,China,at 21:48 Beijing Time(13:48 UTC).Earthquakes with an M3.0 or higher occurred before and after the main shock.Seismic data analysis is essential for the in-depth investigation of the 2021 Yangbi M_(S)6.4 earthquake sequence and the seismotectonics of northwestern Yunnan.Institute of Geophysics,China Earthquake Administration(CEA),has compiled a dataset of seismological observations from 157 broadband stations located within 500 km of the epicenter,and has made this dataset available to the earthquake science research community.The dataset(total file size:329 GB)consists of event waveforms with a sampling frequency of 100 sps collected from 18 to 28 May 2021,20-Hz and 100-Hz continuous waveforms collected from 12 to 31 May 2021,and seismic instrument response files.To promote data sharing,the dataset also includes the seismic event waveforms from 20 to 22 May 2021 recorded at 50 stations of the ongoing Binchuan Active Source Geophysical Observation Project,for which the data protection period has not expired.Sample waveforms of the main shock are included in the appendix of this article and can be downloaded from the Earthquake Science website.The event and continuous waveforms are available from the Earthquake Science Data Center website(www.esdc.ac.cn)on application. 展开更多
关键词 Yangbi earthquake seismological dataset geophys-ical observation data share
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Clinical Research of Zhenwu Decoction Combined with Tingli Dazao Xiefei Decoction in the Treatment of Chronic Heart Failure with Edema Syndrome due to Yang Deficiency
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作者 Ziyang WU Jing SUN jun yang 《Medicinal Plant》 CAS 2022年第2期50-54,共5页
[Objectives]The paper was to investigate the clinical effects of Zhenwu Decoction combined with Tingli Dazao Xiefei Decoction in the treatment of chronic heart failure with edema syndrome due to yang deficiency.[Metho... [Objectives]The paper was to investigate the clinical effects of Zhenwu Decoction combined with Tingli Dazao Xiefei Decoction in the treatment of chronic heart failure with edema syndrome due to yang deficiency.[Methods]Eighty patients with chronic heart failure were randomly divided into 2 groups(control group and treatment group),with 40 cases in each group.The patients in the control group were treated with conventional western medicine for 14 d,and the patients in the treatment group were treated with Zhenwu Decoction and Tingli Dazhao Xiefeng Decoction on the basis of the control group for 14 d.The curative effect of traditional Chinese medicine(TCM)syndrome score,left ventricular ejection fraction(LVEF),plasma N-terminal brain natruretic peptide precursor(NT-proBNP)and New York Heart Association(NYHA)functional class were compared between the two groups before and after treatment.Minnesota living with heart failure questionnaire in the principle of Chinese civilization and traditional medicine characteristics(C-MLHF)at admission and 1 month after discharge were compared between the two groups.[Results]After treatment,the total effective rate of TCM syndrome score in the treatment group was 82.50%,and that in the control group was 67.50%.The curative effect of TCM syndrome score in the treatment group was better than that in the control group(P<0.05).After treatment the LVEF in both groups was increased compared with that before treatment,and the NT-proBNP level was decreased compared with that before treatment(P<0.05),and those in the treatment group were better than those in the control group.The total effective rate of cardiac function in the treatment group was 87.50%,and that in the control group was 65.00%.The improvement of cardiac function in the treatment group was better than that in the control group(P<0.05).One month after discharge,C-MLHF scores in both groups were decreased compared with those before treatment,and that in the treatment group was lower than in the control group(P<0.05).[Conclusions]Zhenwu Decoction combined with Tingli Dazao Xiefei Decoction based on traditional western medicine treatment could improve the clinical efficacy,symptoms and quality of life of patients in the treatment of chronic heart failure with edema syndrome due to yang deficiency. 展开更多
关键词 Chronic heart failure Edema syndrome due to yang deficiency Zhenwu Decoction Tingli Dazao Xiefei Decoction Traditional Chinese medicine syndrome score Cardiac function Quality of life
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Effects of Angiotensin II on Expression of the Gap Junction Channel Protein Connexin 43 in Neonatal Rat Ventricular Myocytes
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作者 jun yang Wei Wu 《South China Journal of Cardiology》 CAS 2007年第4期206-211,共6页
Objectives To study the effects of angiotensin II, as a mediator of cardiac hypertrophy, on expression of connexin 43 (Cx43) in cultured neonatal rat ventricular myocytes and correlation of expression of Cx43 and card... Objectives To study the effects of angiotensin II, as a mediator of cardiac hypertrophy, on expression of connexin 43 (Cx43) in cultured neonatal rat ventricular myocytes and correlation of expression of Cx43 and cardiomyocyte hypertrophy. Methods Cardiomyocytes were isolated from newborn SD rats. Angiotensin II was added into the media to induce myocyte hypertrophy. Cultures were exposed to 10~6 mol/L angiotensin II for 72 h, Cx43 expression was characterized by RT-PCR and Immunofluorescence methods. Results Immunofluorescence analysis revealed decreased Cx43 immunoreactivity in cells treated for 72 h with angiotensin II. RT-PCR analysis demonstrated there was an obvious decrease of Cx43 mRNA level in cells exposed to angiotensin II for 72 h. The changes of expression of connexin 43 were related to its entrance into S phase of the cell cycle. Cultured neonatal rat cardiomyocytes were exposed for 72 h to increase concentrations of angiotensin II (1.0×10-9~1.0×10-6mol/L), resulting in significantly decreased Cx43 expression. Conclusions Angiotensin II leads to a concentration-dependent decrease in Cx43 protein in cultured neonatal rat ventricular myocytes by decreasing Cx43 mRNA synthesis. Signal transduction pathways activated by angiotensin II under pathophysiologic conditions of cardiac hypertrophy could initiate remodeling of gap junctions. 展开更多
关键词 心室肌细胞 血管紧张素Ⅱ 连接蛋白 间隙交接
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应用微视野计评估弱视儿童的黄斑光敏感度和固视稳定性 被引量:2
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作者 李芳 杨军 +1 位作者 吴挺飞 龙登虹 《国际眼科杂志》 CAS 北大核心 2023年第1期43-47,共5页
目的:应用微视野计评估屈光参差性弱视儿童的黄斑光敏感度及固视稳定性。方法:横断面研究。纳入2020-07/2022-01初次诊断为单眼屈光参差性弱视的儿童39例(弱视眼39眼,对侧眼39眼)和同期纳入最佳矫正视力(BCVA)正常的屈光不正患者42例,... 目的:应用微视野计评估屈光参差性弱视儿童的黄斑光敏感度及固视稳定性。方法:横断面研究。纳入2020-07/2022-01初次诊断为单眼屈光参差性弱视的儿童39例(弱视眼39眼,对侧眼39眼)和同期纳入最佳矫正视力(BCVA)正常的屈光不正患者42例,选取右眼作为正常对照组。利用微视野计(MP-3)测量弱视眼、对侧眼和正常对照组的黄斑中心凹10°范围平均光敏感度和固视稳定性[包括2°和4°范围内固视点百分比(P1,P2),68.2%、95.4%及99.6%双曲线椭圆面积(BCEA)],比较弱视眼、对侧眼和正常对照组的平均光敏感度和固视稳定性的差异。结果:弱视眼组患者黄斑区光敏感度较对侧眼组、正常对照组低(均P<0.017),对侧眼组与正常对照组患者黄斑区光敏感度比较无差异(P=0.555)。弱视眼组患者P1均小于对侧眼组和正常对照组(均P<0.017);对侧眼组与正常对照组患者P1比较无差异(P=0.887)。三组患者P2、68.2%BCEA、95.4%BCEA、99.6%BCEA比较均无差异(均P>0.05)。弱视眼组、对侧眼组和正常对照组患者BCVA均与AT、P1、P2、68.2%BCEA、95.4%BCEA、99.6%BCEA无相关性(均P>0.05)。结论:屈光参差性弱视眼的黄斑视网膜光敏感度和2°范围内的固视稳定性可能降低。 展开更多
关键词 微视野计 弱视 屈光参差 黄斑光敏感度 固视稳定性
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氮掺杂多孔碳负载Fe纳米颗粒用于高性能电催化还原CO_(2)与Zn-CO_(2)电池 被引量:1
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作者 杨文倩 薛自前 +9 位作者 杨俊 冼家慧 刘庆林 范雅楠 郑凯 廖锫钦 苏徽 刘庆华 李光琴 苏成勇 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2023年第5期185-194,共10页
电催化CO_(2)还原为CO因其技术与经济上的可行性而被认为是推进碳中和最有前景的反应之一.然而,水溶液中激烈的竞争性析氢反应阻碍生成单一高选择性产物.目前,贵金属纳米催化剂表现出较好的CO选择性,但稀缺性和高成本限制了其进一步应用... 电催化CO_(2)还原为CO因其技术与经济上的可行性而被认为是推进碳中和最有前景的反应之一.然而,水溶液中激烈的竞争性析氢反应阻碍生成单一高选择性产物.目前,贵金属纳米催化剂表现出较好的CO选择性,但稀缺性和高成本限制了其进一步应用.Fe纳米颗粒(NPs)具有电催化活性,且储量丰富成本低,被认为是一种潜在可替代贵金属的电催化剂,但Fe存在易氧化、团聚、稳定性差、吸附CO_(2)能力低等问题.因此,探索同时具有良好活性和稳定性的新型Fe NPs催化剂仍具有重要意义.金属-有机骨架(MOFs)衍生物被认为是合成锚定和激活金属纳米颗粒的良好前驱体.因此,将Fe NPs固定在MOFs衍生物中为开发稳定、高活性的Fe NPs催化剂提供了可行的机会.本文通过修饰MOFs前驱体的策略,对IRMOF-3(Zn)进行少量含铁配体单羧酸二茂铁的取代,结合一步热解碳化,制备了Fe NPs负载在海绵状氮掺杂多孔碳的复合催化剂(Fe@NPC).同时对配体为对苯二甲酸的MOF-5和配体为2-氨基-对苯二甲酸的IRMOF-3(Zn)进行热解碳化,制备了对照样品多孔碳MOF-5-D和氮掺杂多孔碳IRMOF-3-D.光电子能谱(XPS)和X射线吸收精细结构谱(XAFS)结果表明,在Fe@NPC中含有大量的Fe-Fe键以及极少量的Fe-N/C键,说明Fe主要以纳米颗粒形式存在,少量Fe-N/C分布在Fe NPs表面,在Fe NPs与氮掺杂碳基底间起到良好的连接作用.此外,Fe@NPC具有较大的比表面积(1264 m^(2)g^(-1))和高于MOF-5-D与IRMOF-3-D的CO_(2)吸附能力(93.5 cm^(3)g^(-1)),这种具有CO_(2)强吸附和丰富活性位点的多级孔结构为加速传质、加快CO_(2)转化奠定了良好的基础.在H-cell与-0.6 V_(RHE)的条件下,IRMOF-3-D的最大CO法拉第效率(FECO)为65.3%,是MOF-5-D(49.9%)的1.3倍,说明氮掺杂在一定程度上促进了CO_(2)的电还原.此外,Fe@NPC在-0.3 V_(RHE)到1.0 V_(RHE)的宽电位化学区间均表现出较好的性能,即最大的电流密度,最低的起始电位以及92.1%的最高的FECO.而且Fe@NPC在流动池中可以获得更高的FECO(96.4%),同时能够在H-cell与流动池中均保持良好的稳定性.由于*COOH高能垒,它的产生被认为是高效电化学CO_(2)-CO转换的瓶颈.进一步采用原位衰减全反射-傅里叶变换红外(ATR-IR)来实时监测中间体,并深入探究Fe@NPC作用于CO_(2)还原过程的机理,观测到中间体*COOH的逐渐形成和积累,以及同一反应时间内*COOH在Fe@NPC上的更快动力学形成过程;进一步说明Fe位点与氮掺杂多孔碳之间的协同作用显著提高了Fe@NPC的CO_(2)的捕获能力和传质能力并加速了CO生成的动力学.本文以Fe@NPC为阴极组装了Zn-CO_(2)电池,发现该电池具有良好的充电放电性能,放电过程中可提供3.0 mW cm^(-2)的峰值功率密度,同时表现出良好的稳定性(120个循环),实现CO_(2)电还原与储能的良好结合,并表现出高效的能量转换装置的良好应用潜力.综上,本文为设计用于高选择性的CO_(2)还原反应和能量转换器件的铁基催化剂提供了一种新方法. 展开更多
关键词 Fe纳米颗粒 MOFs衍生物 氮掺杂多孔碳 CO_(2)电催化 Zn-CO_(2)电池
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在N掺杂碳纳米管/纳米线耦合超结构中原位固载CoNi纳米颗粒制备莫特-肖特基催化剂并用于高效电催化氧还原反应
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作者 夏苏为 周其兴 +6 位作者 孙若栩 陈立章 张明义 庞欢 徐林 杨军 唐亚文 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2023年第11期278-289,共12页
设计开发可用于电催化氧还原反应(ORR)的高效催化剂对于推进可持续能源技术(如燃料电池和金属空气电池等)的进一步发展至关重要.然而,由于ORR涉及多电子转移过程,并且动力学迟缓,电位高,从而限制了相关技术的实际应用.到目前为止,铂族... 设计开发可用于电催化氧还原反应(ORR)的高效催化剂对于推进可持续能源技术(如燃料电池和金属空气电池等)的进一步发展至关重要.然而,由于ORR涉及多电子转移过程,并且动力学迟缓,电位高,从而限制了相关技术的实际应用.到目前为止,铂族金属被认为是ORR的基准电催化剂.然而,由于铂族金属资源稀缺、价格高、催化剂稳定性不足阻碍了其在不同能源装置中的进一步应用.因此,亟需开发出高活性、低成本、耐用的ORR电催化剂,从而推进可再生能源技术的进一步发展.双金属纳米合金因具有良好的导电性、可调整的电子态且金属间存在协同效应而被认为是一种有较大应用前景的ORR催化材料.本文采用自我牺牲模板法,将均匀的Co Ni合金纳米颗粒原位封装在N掺杂碳纳米管/纳米线耦合的分层结构中,构建了莫特-肖特基电催化剂(CoNi@N-CNT/NWs),并应用于金属空气电池.采用X射线衍射、拉曼光谱、热重、BET比表面积测试、X射线光电子能谱、扫描电子显微镜和透射电镜等方法对催化剂进行了表征.扫描电子显微镜和透射电镜结果表明,复合材料呈现一维多级结构的纳米管分支/纳米线主干的层次结构.实验结果和理论计算表明,CoNi纳米合金与N掺杂碳纳米管/纳米线的整流接触可以诱导自驱动电荷在莫特-肖特基异质结上转移,从而提高了电子转移效率并调节电荷分布.此外,碳分支/主干型分层结构作为支架的建立,增加了CoNi@N-CNT/NWs材料中活性位点的暴露,避免了材料堆积或聚集,进而提高了机械稳定性,缩短了传质扩散的路径并提高了气体传质的速率.得益于结构和电子优势,CoNi@N-CNT/NWs具有较好的ORR性能,其半波电位(E1/2)为0.86 V,在0.1 molL^(-1)KOH电解质中表现出较好的稳定性.采用CoNi@N-CNT/NWs电催化剂组装的锌空电池可以实现较高的开路电压、高峰值功率密度以及大比容量和持久的循环性能,在不同ORR相关的能源装置中展示出良好的应用前景.综上所述,金属空气电池是未来最具有潜力的能源转换器件之一,双金属纳米合金的精细设计和结构调控将为氧还原催化剂的可控制备和性能优化提供新思路. 展开更多
关键词 CoNi合金 碳纳米管 碳纳米线 氧还原反应 锌空气电池
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SbMYB3 transcription factor promotes root-specific f lavone biosynthesis in Scutellaria baicalensis 被引量:2
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作者 Yumin Fang Jie Liu +8 位作者 Minmin Zheng Sanming Zhu Tianlin Pei Mengying Cui Lijing Chang Hanwen Xiao jun yang Cathie Martin Qing Zhao 《Horticulture Research》 SCIE CSCD 2023年第2期160-169,共10页
Scutellaria baicalensis Georgi produces abundant root-specific f lavones(RSFs),which provide various benefits to human health.We have elucidated the complete biosynthetic pathways of baicalein and wogonin.However,the ... Scutellaria baicalensis Georgi produces abundant root-specific f lavones(RSFs),which provide various benefits to human health.We have elucidated the complete biosynthetic pathways of baicalein and wogonin.However,the transcriptional regulation of f lavone biosynthesis in S.baicalensis remains unclear.We show that the SbMYB3 transcription factor functions as a transcriptional activator involved in the biosynthesis of RSFs in S.baicalensis.Yeast one-hybrid and transcriptional activation assays showed that SbMYB3 binds to the promoter of flavone synthase II-2(SbFNSII-2)and enhances its transcription.In S.baicalensis hairy roots,RNAi of SbMYB3 reduced the accumulation of baicalin and wogonoside,and SbMYB3 knockout decreased the biosynthesis of baicalein,baicalin,wogonin,and wogonoside,whereas SbMYB3 overexpression enhanced the contents of baicalein,baicalin,wogonin,and wogonoside.Transcript profiling by qRT–PCR demonstrated that SbMYB3 activates SbFNSII-2 expression directly,thus leading to more abundant accumulation of RSFs.This study provides a potential target for metabolic engineering of RSFs. 展开更多
关键词 abundant von SPECIFIC
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Artificial nerve graft constructed by coculture of activated Schwann cells and human hair keratin for repair of peripheral nerve defects 被引量:1
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作者 Han-jun Qin Hang Li +5 位作者 jun-Ze Chen Kai-Rui Zhang Xing-Qi Zhao Jian-Qiang Qin Bin Yu jun yang 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第5期1118-1123,共6页
Studies have shown that human hair keratin(HHK) has no antigenicity and excellent mechanical properties. Schwann cells, as unique glial cells in the peripheral nervous system, can be induced by interleukin-1β to secr... Studies have shown that human hair keratin(HHK) has no antigenicity and excellent mechanical properties. Schwann cells, as unique glial cells in the peripheral nervous system, can be induced by interleukin-1β to secrete nerve growth factor, which promotes neural regeneration. Therefore, HHK with Schwann cells may be a more effective approach to repair nerve defects than HHK without Schwann cells. In this study, we established an artificial nerve graft by loading an HHK skeleton with activated Schwann cells. We found that the longitudinal HHK microfilament structure provided adhesion medium, space and direction for Schwann cells, and promoted Schwann cell growth and nerve fiber regeneration. In addition, interleukin-1β not only activates Schwann cells, but also strengthens their activity and increases the expression of nerve growth factors. Activated Schwann cells activate macrophages, and activated macrophages secrete interleukin-1β, which maintains the activity of Schwann cells. Thus, a beneficial cycle forms and promotes nerve repair. Furthermore, our studies have found that the newly constructed artificial nerve graft promotes the improvements in nerve conduction function and motor function in rats with sciatic nerve injury, and increases the expression of nerve injury repair factors fibroblast growth factor 2 and human transforming growth factor B receptor 2. These findings suggest that this artificial nerve graft effectively repairs peripheral nerve injury. 展开更多
关键词 artificial nerve graft bioactive human hair keratin INTERLEUKIN-1Β MACROPHAGES nerve graft nerve growth factor nerve repair peripheral nervous injury Schwann cells
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Recent advances in regulating the performance of acid oxygen reduction reaction on carbon-supported non-precious metal single atom catalysts 被引量:1
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作者 Yanqiu Wang Jiayu Hao +6 位作者 yang Liu Min Liu Kuang Sheng Yue Wang jun yang Jie Li Wenzhang Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第1期601-616,I0015,共17页
Developing high performance and low-cost catalysts for oxygen reduction reaction(ORR)in challenging acid condition is vital for proton-exchange-membrane fuel cells(PEMFCs).Carbon-supported nonprecious metal single ato... Developing high performance and low-cost catalysts for oxygen reduction reaction(ORR)in challenging acid condition is vital for proton-exchange-membrane fuel cells(PEMFCs).Carbon-supported nonprecious metal single atom catalysts(SACs)have been identified as potential catalysts in the field.Great advance has been obtained in constructing diverse active sites of SACs for improving the performance and understanding the fundamental principles of regulating acid ORR performance.However,the ORR performance of SACs is still unsatisfactory.Importantly,microenvironment adjustment of SACs offers chance to promote the performance of acid ORR.In this review,acid ORR mechanism,attenuation mechanism and performance improvement strategies of SACs are presented.The strategies for promoting ORR activity of SACs include the adjustment of center metal and its microenvironment.The relationship of ORR performance and structure is discussed with the help of advanced experimental investigations and theoretical calculations,which will offer helpful direction for designing advanced SACs for ORR. 展开更多
关键词 Oxygen reduction reaction Single atom catalysts Microenvironment of center metal Regulation of center metal atoms Electron structure Proton-exchange-membrane fuel cells
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Impact of mechanical stimulation on the life cycle of horticultural plant 被引量:1
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作者 Zhengguang Liu Tobi Fadiji +2 位作者 jun yang Zhiguo Li Fideline Tchuenbou-Magaia 《Horticultural Plant Journal》 SCIE CAS CSCD 2023年第3期381-394,共14页
Mechanical stimulation technology is critical in agricultural crop production because it is constantly regarded as a developing green technology to regulate plants to meet people's need for green and healthy agric... Mechanical stimulation technology is critical in agricultural crop production because it is constantly regarded as a developing green technology to regulate plants to meet people's need for green and healthy agricultural products. Various environmental mechanical stimulation impacts seed germination, seedling growth, flowering date, fruit quantity, and fruit quality throughout the life cycle of a horticultural plant. This study first outlines the basic characteristics of six types of common mechanical stimulation in nature:precipitation, wind, gravity,touch, sound, and vibration. The effects of various mechanical stimulation types on the seed, seedling, flowering, and fruit of horticultural plants throughout their whole life cycle are then presented, as reviewed in the recent 100 years of existing literature. Finally, potential future study directions are discussed. The main challenge in mechanical stimulation technology is to uncover its potential capabilities for regulating and controlling plant development and fruit quality in green agriculture instead of agricultural chemicals. 展开更多
关键词 Mechanical stimulation PLANT SEED SEEDLING FLOWERING FRUIT
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Where is the optimal plane to mobilize the anterior rectal wall in female patients undergoing total mesorectal excision? 被引量:1
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作者 Wei Jin jun yang +8 位作者 Xin-Yu Li Wei-Cheng Wang Wen-Jian Meng You Li Yi-Chao Liang Yi-Ming Zhou Xin-Dong yang yang-yang Li Shao-Tang Li 《World Journal of Gastroenterology》 SCIE CAS 2023年第19期2992-3002,共11页
BACKGROUND Since Heald proposed the total mesorectal excision(TME)procedure,the prognosis of patients with rectal cancer has been significantly improved.But Heald did not specifically describe the anterior surgical pl... BACKGROUND Since Heald proposed the total mesorectal excision(TME)procedure,the prognosis of patients with rectal cancer has been significantly improved.But Heald did not specifically describe the anterior surgical plane in female patients.And the surgical plane for mobilizing the anterior rectal wall during TME surgery in female patients remains controversial.AIM To investigate the anatomy of the female pelvis and identify the optimal plane for mobilizing the anterior rectal wall.METHODS We retrospectively collected surgical procedure videos and clinical data of female patients diagnosed with middle or low rectal cancer who underwent the TME procedure between January 2020 and October 2022 across six hospitals.The patients were divided into two groups based on the surgical approach used to mobilize the anterior rectal wall:The experimental group was to open the peritoneum at the lowest point of the peritonea reflection and enter the plane for mobilizing,while the control group was cut at 0.5-1 cm above the peritoneal reflection and enter another plan.Then,we compared the preoperative and postoperative information between the two groups.We also dissected and observed ten adult female pelvises to analyze the anatomic structure and compare the entry plane between the two approaches.Finally,we researched the pathological structure between the rectum and the vagina.RESULTS Finally,77 cases that met the criteria were included in our study.Our observations revealed that the experimental group underwent a smooth procedure,entering the plane amidst the mesorectal fascia and adventitia of the vagina,whereas the control group entered the plane between the vaginal adventitia and muscle layers.Compared to the control group,the experimental group showed a significant decrease in intraoperative bleeding[22.5(19.5-50)mL vs 17(5-20)mL,P=0.01],as well as a shorter duration of hospitalization[9(7-11.25)d vs 7(6-10)d,P=0.03].Through the examination of surgical videos and cadaveric studies,we discovered that Denonvilliers'fascia is absent in females.Additionally,pathological sections further revealed the absence of Denonvilliers'fascia in females,with only loose connective tissue present between the mesorectal fascia and adventitia of the vagina.CONCLUSION The plane amidst the mesorectal fascia and vaginal adventitia is the optimal surgical plane to mobilize the anterior rectal wall for female patients undergoing the TME procedure. 展开更多
关键词 Rectal cancer Procedure Female Rectal surgery specialty FASCIA LAPAROSCOPIC
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Reactive template-derived interfacial engineering of CoP/CoO heterostructured porous nanotubes towards superior electrocatalytic hydrogen evolution 被引量:1
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作者 Qixing Zhou Ruoxu Sun +7 位作者 Yiping Ren Run Tian jun yang Huan Pang Kai Huang Xinlong Tian Lin Xu Yawen Tang 《Carbon Energy》 SCIE CAS CSCD 2023年第1期194-205,共12页
The development of economical,efficient,and robust electrocatalysts toward the hydrogen evolution reaction(HER)is highly imperative for the rapid advancement of renewable H2 energy-associated technologies.Extensive ut... The development of economical,efficient,and robust electrocatalysts toward the hydrogen evolution reaction(HER)is highly imperative for the rapid advancement of renewable H2 energy-associated technologies.Extensive utilization of the heterointerface effect can endow the catalysts with remarkably boosted electrocatalytic performance due to the modified electronic state of active sites.Herein,we demonstrate deliberate crafting of CoP/CoO heterojunction porous nanotubes(abbreviated as CoP/CoO PNTs hereafter)using a self-sacrificial template-engaged strategy.Precise control over the Kirkendall diffusion process of the presynthesized cobalt–aspartic acid complex nanowires is indispensable for the formation of CoP/CoO heterostructures.The topochemical transformation strategy of the reactive templates enables uniform and maximized construction of CoP/CoO heterojunctions throughout all the porous nanotubes.The establishment of CoP/CoO heterojunctions could considerably modify the electronic configuration of the active sites and also improve the electric conductivity,which endows the resultant CoP/CoO PNTs with enhanced intrinsic activity.Simultaneously,the hollow and porous nanotube architectures allow sufficient accessibility of exterior/interior surfaces and molecular permeability,drastically promoting the reaction kinetics.Consequently,when used as HER electrocatalysts,the well-designed CoP/CoO PNTs show Pt-like activity,with an overpotential of only 61 mV at 10mA cm^(−2) and excellent stability in 1.0M KOH medium,exceeding those of the vast majority of the previously reported nonprecious candidates.Density functional theory calculations further substantiate that the construction of CoP/CoO heterojunctions enables optimization of the Gibbs free energies for water adsorption and H adsorption,resulting in boosted HER intrinsic activity.The present study may provide in-depth insights into the fundamental mechanisms of heterojunction-induced electronic regulation,which may pave the way for the rational design of advanced Earth-abundant electrocatalysts in the future. 展开更多
关键词 HETEROJUNCTION hydrogen evolution reaction porous nanotubes reactive template
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