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中国森林生物多样性监测网络:二十年群落构建机制探索的回顾与展望 被引量:23
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作者 米湘成 王绪高 +8 位作者 沈国春 刘徐兵 宋晓阳 乔秀娟 冯刚 杨洁 毛子昆 徐学红 马克平 《生物多样性》 CAS CSCD 北大核心 2022年第10期207-229,共23页
中国森林生物多样性监测网络(CForBio)目前已经沿纬度梯度从寒温带到热带布设23个大型森林动态样地,监测1,893种木本植物,代表我国木本植物种类的近1/6。CForBio的主要目标之一是研究森林群落的构建机制。本文综述了近20年来CForBio在... 中国森林生物多样性监测网络(CForBio)目前已经沿纬度梯度从寒温带到热带布设23个大型森林动态样地,监测1,893种木本植物,代表我国木本植物种类的近1/6。CForBio的主要目标之一是研究森林群落的构建机制。本文综述了近20年来CForBio在群落构建机制探索方面取得的进展,包括生物多样性时空格局、生境过滤、生物相互作用、局域扩散和区域因素以及利用新技术取得的新认知等。CForBio研究发现:(1)生境过滤和扩散限制共同决定种–面积关系及β多样性等多样性格局,但二者的相对作用在不同样地及不同尺度存在差异;(2)生境过滤对局域群落构建的作用广泛存在,但很难量化其对群落构建的重要性;(3)同种负密度制约在不同气候带样地普遍存在,负密度制约的强度主要由植物菌根类型介导,并随植物生活史类型、功能性状及环境变化而变化;(4)扩散限制在局域群落构建中发挥关键作用,而区域因素如区域地质历史、区域物种库大小等塑造不同生物地理区群落之间的生物多样性差异;(5)宏观和微观两个方面的新技术促进群落构建机制的研究。在宏观方面,遥感技术以低成本使大范围、多尺度的连续群落生物多样性监测和时空比较研究成为可能;另一方面,叶绿体基因技术和代谢组学等微观技术能促进推导群落构建的分子机制。同时,本文还总结了以往研究的不足,并展望了基于森林动态样地开展群落构建机制研究的未来发展,特别强调了:(1)关注群落构建研究中的尺度问题;(2)深入开展多维度(物种、功能和系统发育)、多营养级生物互作相关的研究;(3)拓展全球变化对群落构建影响的研究;(4)融合观测–实验–模型多种手段开展群落构建机制的研究;(5)连结“群落构建理论研究”和“森林管理实践”。总之,中国森林生物多样性监测网络的长期监测和联网研究是森林群落构建机制研究的重要基础,也是推动群落构建理论、解决森林管理难题的重要平台。 展开更多
关键词 森林生物多样性 群落构建 格局 生境过滤 生物相互作用 局域扩散
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MRTF-A通过HOTAIR调控非小细胞肺癌细胞A549的增殖及迁移 被引量:5
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作者 张琨 周渝斌 +1 位作者 冯刚 曾富春 《中国肺癌杂志》 CAS CSCD 北大核心 2019年第2期82-89,共8页
背景与目的非小细胞肺癌(non-small cell lung cancer, NSCLC)作为肺癌的一种,由于其高发病率一直备受关注。准确揭示其发病机制对于NSCLC的诊断以及治疗具有重要的指导意义。MATF-A作为转录调控因子在多种肿瘤的发生发展过程中发挥着... 背景与目的非小细胞肺癌(non-small cell lung cancer, NSCLC)作为肺癌的一种,由于其高发病率一直备受关注。准确揭示其发病机制对于NSCLC的诊断以及治疗具有重要的指导意义。MATF-A作为转录调控因子在多种肿瘤的发生发展过程中发挥着重要作用,可以调控多种肿瘤细胞的迁移过程。HOTAIR是近年研究发现的一个长链非编码RNA,在多种肿瘤中异常表达并参与多种肿瘤的增殖及迁移的进程。本研究旨在探究MRTF-A通过HOTAIR调控NSCLC的增殖及迁移进程。方法构建MRTF-A的过表达质粒及干扰质粒,检测对A549细胞增殖及迁移的影响。设计合成HOTAIR的si RNA检测对A549细胞增殖及迁移的作用。q RT-PCR检测MRTF-A对HOTAIR表达的调控作用。构建HOTAIR的启动子检测MRTF-A对HOTAIR启动子活性的影响。结果过表达MRTF-A促进A549细胞的增殖,沉默MRTF-A的表达抑制A549细胞的增殖及迁移。干扰HOTAIR的表达抑制A549细胞的增殖及迁移。MRTF-A能够影响HOTAIR的表达,同时能够调控HOTAIR启动子的活性。结论 MRTF-A通过HOTAIR调控NSCLCA549细胞的增殖及迁移进程。 展开更多
关键词 肺肿瘤 MRTF-A HOTAIR 增殖 迁移
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An ultra energy-saving mechanism based on beacon signals for 6G networks
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作者 Ailin Deng Xiaoqian Li +1 位作者 gang feng Lu Guan 《Digital Communications and Networks》 2025年第5期1330-1342,共13页
Terahertz(THz) and millimeter Wave(mmWave) have been considered as potential frequency bands for 6G cellular systems to meet the need of ultra-high data rates. However, indoor communications could be blocked in THz/mm... Terahertz(THz) and millimeter Wave(mmWave) have been considered as potential frequency bands for 6G cellular systems to meet the need of ultra-high data rates. However, indoor communications could be blocked in THz/mmW cellular systems due to the high free-space propagation loss. Deploying a large number of small base stations indoors has been considered as a promising solution for solving indoor coverage problems. However, base station dense deployment leads to a significant increase in system energy consumption. In this paper, we develop a novel ultra-efficient energy-saving mechanism with the aim of reducing energy consumption in 6G distributed indoor base station scenarios. Unlike the existing relevant protocol framework of 3GPP, which operates the cellular system based on constant system signaling messages(including cell ID, cell reselection information, etc.), the proposed mechanism eliminates the need for system messages. The intuition comes from the observation that the probability of having no users within the coverage area of an indoor base station is high, hence continuously sending system messages to guarantee the quality of service is unnecessary in indoor scenarios. Specifically, we design a dedicated beacon signal to detect whether there are users in the coverage area of the base station and switch off the main communication module when there are no active users for energy saving. The beacon frame structure is carefully designed based on the existing 3GPP specifications with minimal protocol modifications, and the protocol parameters involved are optimized. Simulation results show that the proposed mechanism can reduce the system energy from the order of tens of watts to the order of hundreds of milliwatts. Compared to traditional energy-saving schemes, the proposed mechanism achieves an average energy-saving gain of 58%, with a peak energy-saving gain of 90%. 展开更多
关键词 6G Indoor coverage Energy saving User detection Beacon signal
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Symptom Experiences and Coping Patterns in Pancreatic Cancer Patients During Chemotherapy:A Qualitative Study
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作者 Xin Tian Ping Chen +12 位作者 Wen Zhou Peiyang Mao Jian Li Cheng Lei Xiaojing Xue Changlin Li Yuxian Nie feng Gao Jie Li gang feng Xiaobo Du Qiuling Shi Jingyu Zhang 《Proceedings of Anticancer Research》 2025年第1期82-96,共15页
Objective:To explore symptom experiences and self-coping patterns during the early and late stages of chemotherapy in these patients to provide a basis for developing targeted symptom management strategies.Methods:A t... Objective:To explore symptom experiences and self-coping patterns during the early and late stages of chemotherapy in these patients to provide a basis for developing targeted symptom management strategies.Methods:A total of 27 patients with pancreatic cancer undergoing chemotherapy at two medical institutions were recruited between November 2023 and August 2024.Semi-structured interviews were conducted in person or over the phone.Data were analyzed using traditional content and thematic analyses.Results:Three themes were identified:symptom experience,self-coping patterns,and existing obstacles.During the early stages of chemotherapy,patients reported a higher frequency of unpleasant symptoms and recognized these symptoms earlier in the treatment course.Patients in the early stages primarily relied on external support to cope with symptoms,while those in the later stages adopted self-care strategies.Several challenges related to unpleasant symptoms were observed,which appeared to correlate with the self-coping patterns employed.Conclusion:Patients with pancreatic cancer undergoing chemotherapy experience a complex and diverse range of symptoms,with varying coping patterns at different stages of treatment.Symptom management during chemotherapy presents significant challenges.Healthcare providers should improve the ongoing monitoring of symptoms post-chemotherapy.By linking patients’symptom experiences and self-coping patterns at different stages of chemotherapy to their specific challenges,personalized symptom management strategies can be developed to enhance care quality. 展开更多
关键词 Pancreatic cancer CHEMOTHERAPY Symptom experience Self-coping Existing obstacles
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Exploring cellular plasticity and resistance mechanisms in lung cancer:Innovations and emerging therapies
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作者 Caiyu Jiang Shenglong Xie +3 位作者 Kegang Jia gang feng Xudong Ren Youyu Wang 《Journal of Pharmaceutical Analysis》 2025年第5期992-1015,共24页
Non-small cell lung cancer(NSCLC)accounts for the majority of lung cancer cases and remains the leading cause of cancer-related mortality worldwide.Firstly,this review explores the limitations of conventional therapie... Non-small cell lung cancer(NSCLC)accounts for the majority of lung cancer cases and remains the leading cause of cancer-related mortality worldwide.Firstly,this review explores the limitations of conventional therapies,chemotherapy,radiotherapy,and surgery,focusing on the development of drug resistance and significant toxicity that often hinder their efficacy.Thereafter,advancements in targeted therapies,such as immune checkpoint inhibitors(ICIs)and tyrosine kinase inhibitors(TKIs),are discussed,highlighting their impact on improving outcomes for patients with specific genetic mutations,including c-ros oncogene 1 receptor tyrosine kinase(ROS1),anaplastic lymphoma kinase(ALK),and epidermal growth factor receptor(EGFR).Additionally,the emergence of novel immunotherapies and phytochemicals is examined,emphasizing their potential to overcome therapeutic resistance,particularly in advanced-stage diseases.The review also delves into the role of next-generation sequencing(NGS)in enabling personalized treatment approaches and explores the clinical potential of innovative agents,such as bispecific T-cell engagers(BiTEs)and antibody-drug conjugates(ADCs).Finally,we address the socioeconomic barriers that limit the accessibility of these therapies in low-resource settings and propose future research directions aimed at improving the long-term efficacy and accessibility of these treatments. 展开更多
关键词 Lung cancer Targeted therapy Drug resistance Immune checkpoint inhibitors(ICIs) Next-generation sequencing(NGS)
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Effect of iron content and heat treatment on microstructure and mechanical properties of a recycled Al-Si-Mg aluminum alloy
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作者 Sha Lan gang feng +6 位作者 Ya-jun Wang Jin-sheng Zhang Fu-jian Gong Chun Wang Jian-hua Zhao Qing Yang Zhi-bai Wang 《China Foundry》 2025年第2期205-214,共10页
The iron content is one of the most critical parameters affecting the microstructure and mechanical properties of recycled aluminum alloy.This study aimed to compare the microstructure and tensile properties of alloys... The iron content is one of the most critical parameters affecting the microstructure and mechanical properties of recycled aluminum alloy.This study aimed to compare the microstructure and tensile properties of alloys with varying iron content to ascertain the optimal iron content for formulating a recycled Al-Si-Mg aluminum alloy.Additionally,the effects of aging temperature and aging time on the microstructure and mechanical properties of recycled aluminum alloy were investigated.With increasing aging temperature and time,both tensile strength and yield strength are improved,while elongation is decreased.Specifically,when subject to a heat treatment consisting of a solution treatment at 535℃for 5 h followed by an aging treatment at 170℃for5.5 h,the newly designed recycled aluminum alloy achieves a tensile strength of 291 MPa and a yield strength of 238 MPa.These findings hold significant implications for the further development and broader application of recycled aluminum alloys. 展开更多
关键词 recycled aluminum alloy iron content heat treatment MICROSTRUCTURE mechanical property
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黄河流域水鸟多样性季节和区域特征及保护策略 被引量:1
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作者 王春晓 张正旺 +17 位作者 夏少霞 段后浪 王稳 贾亦飞 张立勋 冯刚 杨亚桥 李桐 丁长青 王春平 原宝东 雷进宇 刘宇 石建斌 兰科其 石青青 肖晴 于秀波 《生物多样性》 CSCD 北大核心 2024年第11期209-217,共9页
作为中国候鸟迁飞通道的关键地带和生物多样性的重要区域,黄河流域的水鸟多样性对维持该流域的生态平衡至关重要。本研究基于2022-2023年的黄河流域同步调查数据和公民科学数据,分析了水鸟的种群组成及其季节性特点;并利用物种丰富度、S... 作为中国候鸟迁飞通道的关键地带和生物多样性的重要区域,黄河流域的水鸟多样性对维持该流域的生态平衡至关重要。本研究基于2022-2023年的黄河流域同步调查数据和公民科学数据,分析了水鸟的种群组成及其季节性特点;并利用物种丰富度、Shannon-Wiener多样性指数和Pielou均匀度指数,评估了水鸟多样性在不同季节和区域的特征;同时提出了黄河流域水鸟动态保护策略。结果表明:(1) 2022-2023年,黄河流域共记录到9目20科141种水鸟,其中鸻形目和雁形目水鸟占优势。(2)春季和秋季的水鸟多样性最高,黄河流域不仅是繁殖地和越冬地,还是候鸟迁飞通道中重要的停歇地;(3)下游地区的水鸟丰富度较高,而中游、上游和源区则表现出较高的多样性和均匀度;重点保护物种分布广泛,尤其在春秋季节,中游和下游呈现出明显的集中分布。我们建议在黄河流域的春季和秋季采取全域性保护措施,并根据重点物种的分布季节和区域实施动态的针对性保护。同时,将重点保护水鸟的分布区域纳入迁飞通道行动计划,进行持续性监测。 展开更多
关键词 水鸟多样性 季节和区域特征 保护策略 黄河流域
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TMSN-AA纳米复合物促进人胚胎干细胞向心肌细胞分化的潜在机制研究
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作者 任明明 韩振 +5 位作者 陈立波 李敬来 冯钢 许志锋 黄磊 欧阳春 《中国现代医学杂志》 CAS 2018年第24期13-21,共9页
目的研究优化后的TMSN-AA纳米复合物促进人胚胎干细胞(h ESCs)心肌分化的可能性,并探讨其诱导心肌分化的潜在机制。方法采用优化抗坏血酸(AA)负载的荧光TRITC介孔二氧化硅纳米粒子(TMSN-AA)作为诱导剂,诱导h ESCs细胞心肌分化。通过荧... 目的研究优化后的TMSN-AA纳米复合物促进人胚胎干细胞(h ESCs)心肌分化的可能性,并探讨其诱导心肌分化的潜在机制。方法采用优化抗坏血酸(AA)负载的荧光TRITC介孔二氧化硅纳米粒子(TMSN-AA)作为诱导剂,诱导h ESCs细胞心肌分化。通过荧光定位检测该诱导剂进入细胞情况,流式细胞仪检测其进入细胞后对细胞存活与凋亡的影响,Western blot检测TMSN-AA诱导后,心肌标记基因cTn I、FLK-1以及干性基因OCT4和SOX2的表达以及相关信号通路ERK1/2的激活情况。结果荧光定位发现TMSN-AA可以靶向进入h ESCs细胞,流式细胞仪分析结果显示,二氧化硅和荧光染料四甲基罗丹明修饰介孔二氧化硅不会影响h ESCs的存活和凋亡;且TMSN-AA诱导后,干性基因OCT4和SOX2均下调,且上调心肌标记基因c Tn I和FLK-1的表达。Western blot检测结果显示,TMSN-AA的处理可以激活ERK1/2信号通路,同时证实,该过程Akt信号通路并未参与其中。结论优化后的TMSN-AA纳米载体可以成功进入h ESCs细胞,并靶向诱导其心肌分化,而该诱导过程,至少在一定程度上是通过激活ERK1/2,而不是Akt信号通路实现的。 展开更多
关键词 人胚胎干细胞 抗坏血酸 介孔二氧化硅纳米粒子
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聚合物氮化碳负载铜克级制备一种无需额外配体即可催化二级嘧啶-2-胺的碳-氮乌尔曼偶联反应的实用催化剂 被引量:1
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作者 孙扬阳 冯刚 +2 位作者 陈超 刘永红 张旭 《有机化学》 SCIE CAS CSCD 北大核心 2021年第3期1216-1223,共8页
通过在550℃下煅烧硝酸铜与三聚氰胺前体,可实现聚合物氮化碳负载铜(Cu/PCN)材料的克级制备.X射线光电子能谱(XPS)分析表明,该材料中铜元素呈一价,可在无需额外配体的条件下催化二级嘧啶-2-胺与芳卤代烃的碳-氮乌尔曼偶联反应,以实现其... 通过在550℃下煅烧硝酸铜与三聚氰胺前体,可实现聚合物氮化碳负载铜(Cu/PCN)材料的克级制备.X射线光电子能谱(XPS)分析表明,该材料中铜元素呈一价,可在无需额外配体的条件下催化二级嘧啶-2-胺与芳卤代烃的碳-氮乌尔曼偶联反应,以实现其氮官能团的修饰.作为非均相催化剂,该材料易于回收,并可被重复使用至少五次而不失活.该材料比传统的一价铜与钯催化剂更加活泼,从而为制药工业合成含有嘧啶-2-胺结构的药物提供了一种高效而实用的催化剂. 展开更多
关键词 聚合物氮化碳 催化 碳-氮乌尔曼偶联反应 嘧啶-2-胺
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Physical Safety and Cyber Security Analysis of Multi-Agent Systems:A Survey of Recent Advances 被引量:27
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作者 Dan Zhang gang feng +1 位作者 Yang Shi Dipti Srinivasan 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2021年第2期319-333,共15页
Multi-agent systems(MASs)are typically composed of multiple smart entities with independent sensing,communication,computing,and decision-making capabilities.Nowadays,MASs have a wide range of applications in smart gri... Multi-agent systems(MASs)are typically composed of multiple smart entities with independent sensing,communication,computing,and decision-making capabilities.Nowadays,MASs have a wide range of applications in smart grids,smart manufacturing,sensor networks,and intelligent transportation systems.Control of the MASs are often coordinated through information interaction among agents,which is one of the most important factors affecting coordination and cooperation performance.However,unexpected physical faults and cyber attacks on a single agent may spread to other agents via information interaction very quickly,and thus could lead to severe degradation of the whole system performance and even destruction of MASs.This paper is concerned with the safety/security analysis and synthesis of MASs arising from physical faults and cyber attacks,and our goal is to present a comprehensive survey on recent results on fault estimation,detection,diagnosis and fault-tolerant control of MASs,and cyber attack detection and secure control of MASs subject to two typical cyber attacks.Finally,the paper concludes with some potential future research topics on the security issues of MASs. 展开更多
关键词 CONSENSUS deception attack deny-of-service(DoS)attack fault detection fault estimation fault tolerant control multiagent systems
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Multicenter Clinical Study for Evaluation of Efficacy and Safety of Transdermal Fentanyl Matrix Patch in Treatment of Moderate to Severe Cancer Pain in 474 Chinese Cancer Patients 被引量:6
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作者 Yu-lin Zhu Guo-hong Song +17 位作者 Duan-qi Liu Xi Zhang Kui-feng Liu Ai-hua Zang Ying Cheng Guo-chun Cao Jun Liang Xue-zhen Ma Xin Ding Bin Wang Wei-lian Li Zuo-wei Hu gang feng Jiang-jin Huang Xiao Zheng Shun-chang Jiao Rong Wu Jun Ren 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2011年第4期317-322,共6页
Objective: Although a new matrix formulation fentanyl has been used throughout the world for cancer pain management, few data about its efficacy and clinical outcomes associated with its use in Chinese patients have b... Objective: Although a new matrix formulation fentanyl has been used throughout the world for cancer pain management, few data about its efficacy and clinical outcomes associated with its use in Chinese patients have been obtained. This study aimed to assess the efficacy and safety of the new system in Chinese patients with moderate to severe cancer pain. Methods: A total of 474 patients with moderate to severe cancer pain were enrolled in this study and were treated with the new transdermal fentanyl matrix patch (TDF) up to 2 weeks. All the patients were asked to record pain intensity, side effects, quality of life (QOL), adherence and global satisfaction. The initial dose of fentanyl was 25 ?g/h titrated with opioid or according to National Comprehensive Cancer Network (NCCN) guidelines. Transdermal fentanyl was changed every three days. Results: After 2 weeks. The mean pain intensity of the 459 evaluated patients decreased significantly from 5.63?1.26 to 2.03?1.46 (P<0.0001). The total remission rate was 91.29%, of which moderate remission rate 53.16%, obvious remission rate 25.49% and complete remission rate 12.64%. The rate of adverse events was 33.75%, 18.78% of which were moderate and 3.80% were severe. The most frequent adverse events were constipation and nausea. No fatal events were observed. The quality of life was remarkably improved after the treatment (P<0.0001). Conclusion: The new TDF is effective and safe in treating patients with moderate to severe cancer pain, and can significantly improve the quality of life. 展开更多
关键词 Transdermal fentanyl matrix patch (TDF) Cancer pain EFFICACY Safety Quality of life
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Repair of articular cartilage defects in rabbits through tissue-engineered cartilage constructed with chitosan hydrogel and chondrocytes 被引量:6
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作者 Ming ZHAO Zhu CHEN +6 位作者 Kang LIU Yu-qing WAN Xu-dong LI Xu-wei LUO Yi-guang BAI Ze-long YANG gang feng 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2015年第11期914-923,共10页
Objective: In our previous work, we prepared a type of chitosan hydrogel with excellent biocompatibility. In this study, tissue-engineered cartilage constructed with this chitosan hydrogel and costal chondrocytes was... Objective: In our previous work, we prepared a type of chitosan hydrogel with excellent biocompatibility. In this study, tissue-engineered cartilage constructed with this chitosan hydrogel and costal chondrocytes was used to repair the articular cartilage defects. Methods: Chitosan hydrogels were prepared with a crosslinker formed by combining 1,6-diisocyanatohexane and polyethylene glycol. Chitosan hydrogel scaffold was seeded with rabbit chondrocytes that had been cultured for one week in vitro to form the preliminary tissue-engineered cartilage. This preliminary tissue-engineered cartilage was then transplanted into the defective rabbit articular cartilage. There were three treatment groups: the experimental group received preliminary tissue-engineered cartilage; the blank group received pure chitosan hydrogels; and, the control group had received no implantation. The knee joints were harvested at predetermined time. The repaired cartilage was analyzed through gross morphology, histologically and immunohistochemically. The repairs were scored according to the international cartilage repair society (ICRS) standard. Results: The gross morphology results suggested that the defects were repaired completely in the experimental group after twelve weeks. The regenerated tissue connected closely with subchondral bone and the boundary with normal tissue was fuzzy. The cartilage lacuna in the regenerated tissue was similar to normal cartilage lacuna. The results of ICRS gross and histological grading showed that there were significant differences among the three groups (P〈0.05). Conclusions: Chondrocytes implanted in the scaffold can adhere, proliferate, and secrete extracellular matrix. The novel tissue-engineered cartilage constructed in our research can completely repair the structure of damaged articular cartilage. 展开更多
关键词 Articular cartilage Chitosan hydrogel REPAIR Tissue engineering
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Engineering morphologies of yttrium oxide supported nickel catalysts for hydrogen production 被引量:5
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作者 Rong-Bin Zhang Zi-Ao Tu +7 位作者 Shuai Meng gang feng Zhang-Hui Lu Ying-Zhi Yu Tomas Ramirez Reina Fei-Yang Hu Xiao-Han Chen Run-Ping Ye 《Rare Metals》 SCIE EI CAS CSCD 2023年第1期176-188,共13页
The catalytic performance is highly related to the catalyst structure.Herein,a series of Ni nanoparticles supported on Y_(2)O_(3) with different morphologies were successfully synthesized via hydrothermal process scre... The catalytic performance is highly related to the catalyst structure.Herein,a series of Ni nanoparticles supported on Y_(2)O_(3) with different morphologies were successfully synthesized via hydrothermal process screening different pH environments.These Ni/Y_(2)O_(3)catalysts were applied to efficiently produce CO_(x)-free H2through ammonia decomposition.We identify a significant impact of Y_(2)O_(3)supports on nickel nanoclusters sizes and dispersion.The experimental results show that Ni/Y11 catalyst achieves 100% ammonia decomposition conversion under a gas hour space velocity(GHSV) of 12,000 ml·h^(-1)·gcat^(-1) and temperature of 650℃.Such a high level of activity over Ni/Y11 catalyst was attributed to a large specific surface area,appropriate alkalinity,and small Ni nanoparticles diameter with high dispersion. 展开更多
关键词 Ammonia decomposition Hydrogen production Yttrium oxide morphology Ni catalysts Hydrothermal method
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Adenovirus-mediated GDF-5 promotes the extracellular matrix expression in degenerative nucleus pulposus cells 被引量:4
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作者 Xu-wei LUO Kang LIU +4 位作者 Zhu CHEN Ming ZHAO Xiao-wei HAN Yi-guang BAI gang feng 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2016年第1期30-42,共13页
Objective: To construct a recombinant adenovirus vector-carrying human growth and differentiation factor-5 (GDF-5) gene, investigate the biological effects of adenovirus-mediated GDF-5 (Ad-GDF-5) on extracellular... Objective: To construct a recombinant adenovirus vector-carrying human growth and differentiation factor-5 (GDF-5) gene, investigate the biological effects of adenovirus-mediated GDF-5 (Ad-GDF-5) on extracellular matrix (ECM) expression in human degenerative disc nucleus pulposus (NP) cells, and explore a candidate gene therapy method for intervertebral disc degeneration (IDD). Methods: Human NP cells of a degenerative disc were isolated, cultured, and infected with Ad-GDF-5 using the AdEasy-1 adenovirus vector system. On Days 3, 7, 14, and 21, the contents of the sulfated glycosaminoglycan (sGAG), deoxyribonucleic acid (DNA) and hydroxyproline (Hyp), synthesis of proteoglycan and collagen II, gene expression of collagen II and aggrecan, and NP cell proliferation were assessed. Results: The adenovirus was an effective vehicle for gene delivery with prolonged expression of GDF-5. Biochemical analysis revealed increased sGAG and Hyp contents in human NP cells infected by Ad-GDF-5 whereas there was no conspicuous change in basal medium (BM) or Ad-green fluorescent protein (GFP) groups. Only cells in the Ad-GDF-5 group promoted the production of ECM, as demonstrated by the secretion of proteoglycan and up-regulation of collagen II and aggrecan at both protein and mRNA levels. The NP cell proliferation was significantly promoted. Conclusions: The data suggest that Ad-GDF-5 gene therapy is a potential treatment for IDD, which restores the functions of degenerative intervertebral disc through enhancing the ECM production of human NP ceils. 展开更多
关键词 Intervertebral disc DEGENERATION Growth and differentiation factor-5 (GDF-5) ADENOVIRUS Gene therapy Nucleus pulposus
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Human parvovirus B19-associated early postoperative acquired pure red cell aplasia in simultaneous pancreas-kidney transplantation:A case report 被引量:5
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作者 Hui Wang Ying-Xin Fu +5 位作者 Wen-Li Song Zhen Wang gang feng Jie Zhao Ye-Qi Nian Yu Cao 《World Journal of Clinical Cases》 SCIE 2021年第8期1968-1975,共8页
BACKGROUND Acquired pure red cell aplasia(aPRCA)related to human parvovirus B19(HPV B19)is rarely reported in simultaneous pancreas-kidney transplantation(SPKT)recipients;there has yet to be a case report of early pos... BACKGROUND Acquired pure red cell aplasia(aPRCA)related to human parvovirus B19(HPV B19)is rarely reported in simultaneous pancreas-kidney transplantation(SPKT)recipients;there has yet to be a case report of early postoperative infection.In this current study,we report the case of a Chinese patient who experienced the disease in the early postoperative period.CASE SUMMARY A 63-year-old man,with type 2 diabetes and end-stage renal disease,received a brain dead donor-derived SPKT.Immunosuppression treatment consisted of tacrolimus,prednisone,enteric-coated mycophenolate sodium(EC-MPS),and thymoglobulin combined with methylprednisolone as induction.The hemoglobin(Hb)level declined due to melena at postoperative day(POD)3,erythropoietinresistant anemia persisted,and reticulocytopenia was diagnosed at POD 20.The bone marrow aspirate showed decreased erythropoiesis and the presence of giant pronormoblasts at POD 43.Metagenomic next-generation sequencing(mNGS)of a blood sample identified HPV B19 infection at POD 66.EC-MPS was withdrawn;three cycles of intravenous immunoglobulin(IVIG)infusion therapy were administered;and tacrolimus was switched to cyclosporine.The HPV B19-associated aPRCA resolved completely and did not relapse within the 1-year follow-up period.The diminution in mNGS reads was correlated with Hb and reticulocyte count improvements.CONCLUSION HPV B19-associated aPRCA can occur at an early period after SPKT.An effective therapy regimen includes IVIG infusion and adjustment of the immunosuppressive regimen.Moreover,mNGS can be used for the diagnosis and to reflect disease progression. 展开更多
关键词 ANEMIA Human parvovirus B19 Intravenous immunoglobulin METAGENOMIC Next-generation sequencing Pancreas transplantation Case report
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Effects of reduction temperature and content of Pd loading on the performance Pd/CeO2 catalyst for CO oxidation 被引量:3
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作者 Yue Yan Huaxi Li +3 位作者 Zhanghui Lu Xuewen Wang Rongbin Zhang gang feng 《Chinese Chemical Letters》 SCIE CAS CSCD 2019年第6期1153-1156,共4页
The content of noble metal loading and the reduction process of the catalysts are important factors influence the economic indicator and catalytic performance for industrial catalysis. In the present work, Pd/CeO2NT (... The content of noble metal loading and the reduction process of the catalysts are important factors influence the economic indicator and catalytic performance for industrial catalysis. In the present work, Pd/CeO2NT (Pd supported on the CeO2 nanotubes) catalysts are prepared with the hydrothermal synthesized CeO2NT and glutathione (GSH) reduced Pd nanoparticles via impregnation. The content of Pd loading as well as the catalysts reduction temperature are optimized to the CO oxidation reduction. Our results show that the best Pd loading is 1.5%Pd/CeO2NT. The catalysts reduced at 350 ℃ for 2 h prior to catalytic reaction perform the best toward CO oxidation, which reaches completely CO conversion at 70 ℃. The XRD, Raman, H2-TPR, TEM, BET and XPS characterization reveal that the excellent catalytic performance of 350 °C 1.5%Pd/CeO2NT sample can be attributed the high Pd^0 species and oxygen vacancy in the sample, which are important factors influence the activity of the catalysts. 展开更多
关键词 CO oxidation PALLADIUM CATALYST CERIA NANOTUBES Reduction temperature PALLADIUM content
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Distributed Adaptive Output Consensus of Unknown Heterogeneous Non-Minimum Phase Multi-Agent Systems 被引量:4
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作者 Wenji Cao Lu Liu gang feng 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第4期997-1008,共12页
This article addresses the leader-following output consensus problem of heterogeneous linear multi-agent systems with unknown agent parameters under directed graphs.The dynamics of followers are allowed to be non-mini... This article addresses the leader-following output consensus problem of heterogeneous linear multi-agent systems with unknown agent parameters under directed graphs.The dynamics of followers are allowed to be non-minimum phase with unknown arbitrary individual relative degrees.This is contrary to many existing works on distributed adaptive control schemes where agent dynamics are required to be minimum phase and often of the same relative degree.A distributed adaptive pole placement control scheme is developed,which consists of a distributed observer and an adaptive pole placement control law.It is shown that under the proposed distributed adaptive control scheme,all signals in the closed-loop system are bounded and the outputs of all the followers track the output of the leader asymptotically.The effectiveness of the proposed scheme is demonstrated by one practical example and one numerical example. 展开更多
关键词 Adaptive pole placement control heterogeneous multi-agent systems leader-following output consensus non-minimum phase
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Consensus of single integrator multi-agent systems with directed topology and communication delays 被引量:4
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作者 Xiang XU Lu LIU gang feng 《Control Theory and Technology》 EI CSCD 2016年第1期21-27,共7页
In this paper, a distributed control scheme has been developed for consensus of single integrator multi-agent systems with directed fixed communication topology for arbitrarily large constant, time-varying or distribu... In this paper, a distributed control scheme has been developed for consensus of single integrator multi-agent systems with directed fixed communication topology for arbitrarily large constant, time-varying or distributed communication delays. It is proved that the closed loop control system can reach consensus with an exponential convergence rate if and only if the topology is quasi-strongly connected. Simulation results are also provided to demonstrate the effectiveness of the proposed controller. 展开更多
关键词 CONSENSUS directed fixed topology single integrator multi-agent systems communication delays
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Robust hydrogen production from HCOOH over amino-modified KIT-6-confined Pd Ir alloy nanoparticles 被引量:3
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作者 Wenfang Peng Shiwen Liu +3 位作者 Xiugang Li gang feng Jianhui Xia Zhang-Hui Lu 《Chinese Chemical Letters》 SCIE CAS CSCD 2022年第3期1403-1406,共4页
Formic acid (FA), which can be produced via CO_(2) reduction and biomass conversion, has received extensive interest as a convenient and safe hydrogen carrier due to its wide range of sources, renewable, high hydrogen... Formic acid (FA), which can be produced via CO_(2) reduction and biomass conversion, has received extensive interest as a convenient and safe hydrogen carrier due to its wide range of sources, renewable, high hydrogen content (4.4 wt%), and convenient storage/transportation. Designing highly efficient catalysts is the main challenge to realize the hydrogen production from FA. In this work, well-dispersed and electron-rich PdIr alloy nanoparticles with a size of 1.8 nm are confined in amino-modified 3D mesoporous silica KIT-6 and applied as a highly efficient catalyst for robust hydrogen production from FA at ambient temperature. Small PdIr alloy nanoparticles confined by amino-modified KIT-6 (PdIr/KIT-6-NH_(2)) lead to better catalytic activity compared to that of Pd/KIT-6-NH_(2) and PdIr confined by bare KIT-6, achieving a high turnover frequency (TOF) value of 3533 h-1 at ambient temperature (303 K), 100% H_(2) selectivity and conversion toward the dehydrogenation of FA, which is comparable to the best heterogeneous catalysts ever reported. The high catalytic activity of PdIr/KIT-6-NH_(2) can be attributed to the synergistic effect between Pd and Ir, strong interaction between PdIr and KIT-6-NH_(2), as well as the amino-groups of KIT-6-NH_(2) which can act as a proton scavenger to promote the breaking of O-H bond of formic acid. 展开更多
关键词 Formic acid Hydrogen production PALLADIUM Metal nanoparticle 3D mesoporous silica
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Effect of Zr-doping on Pd/CexZr1-xO2 catalysts for oxidative carbonylation of phenol 被引量:3
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作者 Lichao Zhou gang feng +4 位作者 Xiaojing Liu ZhimiaoWang Fang Li Wei Xue Yanji Wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2020年第10期2592-2599,共8页
Ce–Zr solid solution(CexZr1-xO2,CZO)was prepared by the citric acid sol–gel method.The CZO was then used as a support for Pd/CZO catalysts for the oxidative carbonylation of phenol to diphenyl carbonate.The Pd/CZO c... Ce–Zr solid solution(CexZr1-xO2,CZO)was prepared by the citric acid sol–gel method.The CZO was then used as a support for Pd/CZO catalysts for the oxidative carbonylation of phenol to diphenyl carbonate.The Pd/CZO catalyst showed enhanced activity and diphenyl carbonate selectivity compared with the Pd/CeO2 catalyst.The catalytic performance of Pd/CZO was influenced by the calcination temperature of the CZO support.X-ray diffraction,scanning electron microscopy,N2 adsorption–desorption measurements,X-ray photoelectron spectroscopy and H2 temperature-programmed reduction measurements were used to investigate the effects of Zr doping and calcination temperature.The catalytic performance of Pd/CZO and Pd/CeO2 for the oxidative carbonylation of phenol was affected by several factors,including the specific surface area,Ce^3+and/or oxygen vacancy content,oxygen species type and Pd(II)content of the catalyst.All these properties were influenced by Zr doping and the calcination temperature of the CZO support. 展开更多
关键词 Diphenyl carbonate Oxidative carbonylation Ce–Zr solid solution Zr doping SUPPORT
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