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Response to roxadustat in a patient undergoing long-term dialysis and allergic to erythropoiesis-stimulating agents:A case report
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作者 Cai Xu Deng-Gui Luo +6 位作者 Zhe-Yan Liu Dong Yang Dan-Dan Wang Yuan-Zhao Xu Jun Yang Bo Fu Ai-Rong Qi 《World Journal of Clinical Cases》 SCIE 2022年第35期13122-13128,共7页
BACKGROUND Hypoxia-inducible factor prolyl hydroxylase inhibitor is a new class of drugs for treating renal anemia.It is a second-generation hypoxia-inducible factor prolyl hydroxylase-2(PHD2)inhibitor.Roxadustat can ... BACKGROUND Hypoxia-inducible factor prolyl hydroxylase inhibitor is a new class of drugs for treating renal anemia.It is a second-generation hypoxia-inducible factor prolyl hydroxylase-2(PHD2)inhibitor.Roxadustat can effectively increase hemoglobin in patients with dialysis-dependent chronic kidney disease,with an adverse events profile comparable to that of epoetin alfa.We administered roxadustat to a maintenance hemodialysis patient who was allergic to erythropoiesis-stimulating agents(ESAs)and depended on blood transfusion for five years.After applying Roxadustat,the patient’s anemia improved significantly.CASE SUMMARY A 77-year-old Chinese man had type 2 diabetes for 16 years,underwent maintenance hemodialysis for five years,and had fatigue for five years.Laboratory tests showed severe anemia(hemoglobin concentration of 42 g/L).The patient was administered a subcutaneous injection of ESAs before dialysis.He suffered an allergic shock immediately and fainted.His blood pressure dropped to undetectable levels.He was not administered ESAs henceforth.The patient was prescribed iron supplements and received blood transfusions occasionally for five years.His hemoglobin concentration ranged from 42-68 g/L.After taking six weeks of oral roxadustat three times weekly(100 mg TIW),the patient’s hemoglobin concentration increased significantly,and his symptoms decreased.We adjusted the doses of roxadustat,and the hemoglobin concentration was maintained between 97 and 126 g/L.CONCLUSION Oral roxadustat is effective in treating anemia in maintenance hemodialysis patients who cannot be administered ESAs. 展开更多
关键词 Chronic kidney disease HEMODIALYSIS ANEMIA Roxadustat erythropoiesis-stimulating agents Allergic shock Case report
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Erythropoiesis-stimulating agents in the management of cancer patients with anemia: a meta-analysis 被引量:2
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作者 Xiaomei Li ZhiYan +5 位作者 Dexiao Kong Wen Zou Jihua Wang DianshuiSun Yuhua Jiang Chengyun Zheng 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2014年第3期268-276,共9页
Background: Erythropoiesis-stimulating agents (ESAs) are widely used in the management of anemia in cancer patients. Despite their apparent effectiveness, recent studies have suggested that ESAs could result in ser... Background: Erythropoiesis-stimulating agents (ESAs) are widely used in the management of anemia in cancer patients. Despite their apparent effectiveness, recent studies have suggested that ESAs could result in serious adverse events and even higher mortality. The aim of the current study was to evaluate the benefits and risks of ESAs in the management of cancer patients with anemia using a recta-analysis. Methods: The initial literature search covered Medline, PubMed, Embase, and the Cochrane Center Register of Controlled Trials, and identified 1,569 articles. The final meta-analysis included eight randomized controlled trials (n=2,387) in cancer patients with 〈11 g/dL hemoglobin (Hb) at the baseline and target Hb (for stopping ESA treatment) at no more than 13 g/dL. The assessment measures included Hb response, blood transfusion rate and adverse events that included venous thromboemblism (VTE), hypertension, and on-study mortality. The results are expressed as pooled odds ratio (OR). Publication bias was assessed using funnel plot analysis. Results: ESAs significantly increased the Hb concentration [OR 7.85, 95% confidence interval (CI): 5.85 to 10.53, P〈O.O01] and reduced the red blood cell (RBC) transfusion rate (OR 0.52, 95% CI: 0.42 to 0.65, P〈0.001). ESAs did not increase the accumulated adverse events (OR 0.95, P=0.82), or the on-study mortality (OR 1.09, P=0.47). Conclusions: ESAs are not associated with increased frequency of severe adverse events in anemic cancer patients when the target Hb value is no more than 13 g/dL. 展开更多
关键词 Adverse events ANEMIA CANCER erythropoiesis-stimulafing agents (ESAs)
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基于免疫Agent的电力电缆线路故障检测系统
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作者 吕超 李赫 +2 位作者 刘文杰 郑大鹏 李宁 《电子设计工程》 2024年第1期59-63,共5页
为区别故障信号、非故障信号,实现对电缆线路故障的准确检测,设计了基于免疫Agent的电力电缆线路故障检测系统。利用前端检测电路为故障分析模块、测距方式切换模块提供电量传输信号,完成系统前端检测装置的连接。按照免疫Agent检测原... 为区别故障信号、非故障信号,实现对电缆线路故障的准确检测,设计了基于免疫Agent的电力电缆线路故障检测系统。利用前端检测电路为故障分析模块、测距方式切换模块提供电量传输信号,完成系统前端检测装置的连接。按照免疫Agent检测原理提取电力电缆线路故障信号的特征,联合已获取信号对象,求解检测插值指标的具体数值。结合各级硬件设备结构,完成系统设计。实验结果表明,该系统可同时检测波频为10~20 Hz、40~50 Hz、60~70 Hz的故障信号与波频为20~30 Hz、30~40 Hz、50~60 Hz的非故障信号,可以在精准辨别故障与非故障信号的同时,实现对电力电缆线路故障的准确检测。 展开更多
关键词 免疫agent 电力电缆 线路故障 故障检测 故障特征 检测插值
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基于Agent人工智能的异构网络多重覆盖节点入侵检测系统设计
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作者 顾正祥 《计算机测量与控制》 2024年第5期17-23,30,共8页
异构网络具有结构复杂、多重覆盖面积大等特征,使得网络入侵检测较为隐蔽,威胁网络运行的安全性;为此,对基于Agent人工智能的异构网络多重覆盖节点入侵检测系统进行了研究;通过检测Agent和通信Agent装设主机Agent,以Cisco Stealthwatch... 异构网络具有结构复杂、多重覆盖面积大等特征,使得网络入侵检测较为隐蔽,威胁网络运行的安全性;为此,对基于Agent人工智能的异构网络多重覆盖节点入侵检测系统进行了研究;通过检测Agent和通信Agent装设主机Agent,以Cisco Stealthwatch流量传感器作为异构网络传感器检测攻击行为,采用STM32L151RDT664位微控制器传输批量数据,由MAX3232芯片实现系统电平转化,实现硬件系统设计;软件部分设计入侵检测标准,采用传感器设备捕获网络实时数据,通过Agent技术解析异构网络协议并提取数据运行特征,综合考虑协议解析结果及与检测标准匹配度,实现异构网络多重覆盖节点入侵检测;经实验测试表明,基于Agent人工智能的异构网络多重覆盖节点入侵检测系统入侵行为的漏检率和入侵类型误检率的平均值仅为6%和5%,能够有效提高检测精度,减小检测误差。 展开更多
关键词 agent人工智能 异构网络 多重覆盖网络 入侵检测系统
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基于Multi-Agent的无人机集群体系自主作战系统设计
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作者 张堃 华帅 +1 位作者 袁斌林 杜睿怡 《系统工程与电子技术》 EI CSCD 北大核心 2024年第4期1273-1286,共14页
针对无人集群自主作战体系设计中的关键问题,提出基于Multi-Agent的无人集群自主作战系统设计方法。建立无人集群各节点的Agent模型及其推演规则;对于仿真系统模块化和通用化的需求,设计系统互操作式接口和无人集群自主作战的交互关系;... 针对无人集群自主作战体系设计中的关键问题,提出基于Multi-Agent的无人集群自主作战系统设计方法。建立无人集群各节点的Agent模型及其推演规则;对于仿真系统模块化和通用化的需求,设计系统互操作式接口和无人集群自主作战的交互关系;开展无人集群系统仿真推演验证。仿真结果表明,所提设计方案不仅能够有效开展并完成自主作战网络生成-集群演化-效能评估的全过程动态演示验证,而且能够通过重复随机试验进一步评估无人集群的协同作战效能,最后总结了集群协同作战的策略和经验。 展开更多
关键词 MULTI-agent 无人集群 体系设计 协同作战
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基于多Agent传动关系的股市趋势预测
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作者 鲍志 姚宏亮 +2 位作者 方帅 杨静 俞奎 《计算机工程》 CAS CSCD 北大核心 2024年第3期267-276,共10页
股市趋势预测是机器学习领域中一个具有挑战性的任务。由于一些因素对于股市的影响是动态且不确定的,导致股市趋势难以预测。针对已有方法在股市预测时存在的灵敏性差、适应力弱等问题,从快变量和慢变量的传动关系出发,利用Agent技术对... 股市趋势预测是机器学习领域中一个具有挑战性的任务。由于一些因素对于股市的影响是动态且不确定的,导致股市趋势难以预测。针对已有方法在股市预测时存在的灵敏性差、适应力弱等问题,从快变量和慢变量的传动关系出发,利用Agent技术对股市中的快周期和慢周期进行联合建模,提出一种多Agent传动影响图(MATID)股市趋势预测方法。给出股市中快周期和慢周期的划分标准,并引入周期能量的概念;通过对相关趋势指标的特征融合,给出周期能量的量化计算方法;通过分析快周期和慢周期的动态作用过程,给出传动因子的表示方法;将快周期和慢周期分别对应成不同的Agent,利用多Agent影响图模型建模快周期和慢周期的传动过程;利用股市振子模型表示快Agent和慢Agent之间的传动效用,利用联合树的自动推理技术对股市趋势进行预测。在不同样本数量和不同股市趋势下进行实验,结果表明,与门控循环单元、S-LSTM和Hybrid-RNN预测方法相比,MATID方法预测精确率提升1.5%~7.0%,召回率提升5.4%~6.7%,F1值提升3.7%~6.2%,具有良好的灵敏性和适应力。 展开更多
关键词 agent传动影响图 周期传动 振子模型 效用函数 联合树
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竞争与合作视角下的多Agent强化学习研究进展
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作者 田小禾 李伟 +3 位作者 许铮 刘天星 戚骁亚 甘中学 《计算机应用与软件》 北大核心 2024年第4期1-15,共15页
随着深度学习和强化学习研究取得长足的进展,多Agent强化学习已成为解决大规模复杂序贯决策问题的通用方法。为了推动该领域的发展,从竞争与合作的视角收集并总结近期相关的研究成果。该文介绍单Agent强化学习;分别介绍多Agent强化学习... 随着深度学习和强化学习研究取得长足的进展,多Agent强化学习已成为解决大规模复杂序贯决策问题的通用方法。为了推动该领域的发展,从竞争与合作的视角收集并总结近期相关的研究成果。该文介绍单Agent强化学习;分别介绍多Agent强化学习的基本理论框架——马尔可夫博弈以及扩展式博弈,并重点阐述了其在竞争、合作和混合三种场景下经典算法及其近期研究进展;讨论多Agent强化学习面临的核心挑战——环境的不稳定性,并通过一个例子对其解决思路进行总结与展望。 展开更多
关键词 深度学习 强化学习 agent强化学习 环境的不稳定性
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基于Agent的跨境电子商务课程智能教学系统
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作者 杨宏波 吴亚霄 刘英 《信息与电脑》 2024年第1期168-170,共3页
当前,跨境电子商务课程智能教学系统功能模块多为单向形式,可控教学覆盖范围较小,导致平均成绩优化比下降,为此提出对基于Agent的跨境电子商务课程智能教学系统的设计与分析。首先,构建通信接口,并接入驱动装置,完成系统硬件的设计;其次... 当前,跨境电子商务课程智能教学系统功能模块多为单向形式,可控教学覆盖范围较小,导致平均成绩优化比下降,为此提出对基于Agent的跨境电子商务课程智能教学系统的设计与分析。首先,构建通信接口,并接入驱动装置,完成系统硬件的设计;其次,采用多目标的方式,扩大可控教学覆盖范围;最后,设计多目标Agent跨境电子商务课程教学功能模块,关联跨境电子商务教学知识库,完成系统软件设计。测试结果表明:针对选定的6个班级进行测试对比,最终得出的平均成绩优化比均可以达到20%以上,说明在Agent的辅助下,文章设计的系统应用效果更佳,具有实际的应用价值。 展开更多
关键词 agent 跨境电子商务 商务课程 智能教学 教学系统 系统设计
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Fixed-Time Cluster Optimization for Multi-Agent Systems Based on Piecewise Power-Law Design
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作者 Suna Duan Xinchun Jia Xiaobo Chi 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第5期1301-1303,共3页
Dear Editor,This letter focuses on the fixed-time(FXT)cluster optimization problem of first-order multi-agent systems(FOMASs)in an undirected network,in which the optimization objective is the sum of the objective fun... Dear Editor,This letter focuses on the fixed-time(FXT)cluster optimization problem of first-order multi-agent systems(FOMASs)in an undirected network,in which the optimization objective is the sum of the objective functions of all clusters.A novel piecewise power-law control protocol with cooperative-competition relations is proposed.Furthermore,a sufficient condition is obtained to ensure that the FOMASs achieve the cluster consensus within an FXT. 展开更多
关键词 agent CLUSTER OPTIMIZATION
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Adaptive Consensus of Uncertain Multi-Agent Systems With Unified Prescribed Performance
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作者 Kun Li Kai Zhao Yongduan Song 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第5期1310-1312,共3页
Dear Editor,An adaptive consensus control algorithm for uncertain multi-agent systems(MAS),capable of guaranteeing unified prescribed performance,is presented in this letter.Unlike many existing prescribed performance... Dear Editor,An adaptive consensus control algorithm for uncertain multi-agent systems(MAS),capable of guaranteeing unified prescribed performance,is presented in this letter.Unlike many existing prescribed performance related works,the developed control exhibits some features.Firstly,a distributed prescribed time observer is introduced so that not only each follower is able to estimate the leader’s signal within a predetermined time,but also the control design for each agent is independent with its neighbors. 展开更多
关键词 agent PRESCRIBED UNCERTAIN
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Patent-based technological developments and surfactants application of lithium-ion batteries fire-extinguishing agent
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作者 Jianqi Zhang Tao Fan +4 位作者 Shuai Yuan Chongye Chang Kuo Wang Ziwei Song Xinming Qian 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期39-63,I0002,共26页
While newer,more efficient Lithium-ion batteries(LIBs)and extinguishing agents have been developed to reduce the occurrence of thermal runaway accidents,there is still a scarcity of research focused on the application... While newer,more efficient Lithium-ion batteries(LIBs)and extinguishing agents have been developed to reduce the occurrence of thermal runaway accidents,there is still a scarcity of research focused on the application of surfactants in different LIBs extinguishing agents,particularly in terms of patented technologies.The aim of this review paper is to provide an overview of the technological progress of LIBs and LIBs extinguishing agents in terms of patents in Korea,Japan,Europe,the United States,China,etc.The initial part of this review paper is sort out LIBs technology development in different regions.In addition,to compare LIBs extinguishing agent progress and challenges of liquid,solid,combination of multiple,and microencapsulated.The subsequent section of this review focuses on an in-depth analysis dedicated to the efficiency and challenges faced by the surfactants corresponding design principles of LIBs extinguishing agents,such as nonionic and anionic surfactants.A total of 451,760 LIBs-related patent and 20 LIBs-fire-extinguishing agent-related patent were included in the analyses.The extinguishing effect,cooling performance,and anti-recombustion on different agents have been highlighted.After a comprehensive comparison of these agents,this review suggests that temperature-sensitive hydrogel extinguishing agent is ideal for the effective control of LIBs fire.The progress and challenges of surfactants have been extensively examined,focusing on key factors such as surface activity,thermal stability,foaming properties,environmental friendliness,and electrical conductivity.Moreover,it is crucial to emphasize that the selection of a suitable surfactant must align with the extinguishing strategy of the extinguishing agent for optimal firefighting effectiveness. 展开更多
关键词 LIBS Fire-extinguishing agent SURFACTANTS PATENT
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Progress in the Use of Glucocorticoids and Biological Agents in Non-Infectious Uveitis
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作者 Yuxuan Liu Xunyu Zou +1 位作者 Shizhou Cheng Zuhai Zhang 《Journal of Biosciences and Medicines》 2024年第2期138-155,共18页
One of the main immune-mediated diseases that lead to avoidable blindness is non-infectious uveitis. Glucocorticoids are the first-line therapy choice for noninfectious uveitis;however, biologics are also showing prom... One of the main immune-mediated diseases that lead to avoidable blindness is non-infectious uveitis. Glucocorticoids are the first-line therapy choice for noninfectious uveitis;however, biologics are also showing promise in the management of this condition. The description of glucocorticoid and biologic usage in non-infectious uveitis is the main topic of this paper. 展开更多
关键词 Non-Infectious Uveitis GLUCOCORTICOIDS Biological agents
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Near-Infrared Fluorescence Imaging Contrast Agents for Clinical Research: Limitations and Alternatives
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作者 Serigne Moussa Badiane Elhadji A. L. Bathily +1 位作者 Fawrou Seye Louis A.D. Diouf 《Open Journal of Biophysics》 2024年第1期73-77,共5页
Introduction: Near-infrared fluorescence imaging is a technique that will establish itself in the short term at the international level because it is recognized for its potential to improve the performance of surgical... Introduction: Near-infrared fluorescence imaging is a technique that will establish itself in the short term at the international level because it is recognized for its potential to improve the performance of surgical interventions, its moderate investment and operating costs and its portability. Although the technology is now mature, there is currently the problem of the availability of contrast agents to be injected IV. The aim of this methodology article is to propose an alternative solution to the need for contrast agents for clinical research, particularly in oncology. Methodology: They consist of coupling a fluorescent marker in the form of an NHS derivative, such as IR DYE manufactured in compliance with GMP, with therapeutic monoclonal antibodies having marketing authorization for molecular imaging. For a given antibody, the marking procedure must be the subject of a validation file on the final preparation filtered on a sterilizing membrane at 0.22 μm. Once the procedure has been validated, it would be unnecessary to repeat the tests before each clinical research examination. A check of the marking by thin-layer chromatography (TLC) and place it in a sample bank at +4˚C for 1 month of each injected formulation would be sufficient for additional tests if necessary. Conclusion: Molecular near-infrared fluorescence imaging is experiencing development, the process of which could be accelerated by greater availability of clinical contrast agents. Alternative solutions are therefore necessary to promote clinical research in this area. These methods must be shared to make it easier for researchers. 展开更多
关键词 Fluorescence Imaging Contrast agents Clinical Research
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Preparation of Tartary Buckwheat Seed Coating Agent and Its Effect on Germination
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作者 Xin Zou Jieyu Zhang +6 位作者 Ting Cheng Yangyang Guo Xiao Han Han Liu Yuxing Qin Jie Li Dabing Xiang 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第4期699-712,共14页
To mitigate the wastage of seed resources and reduce the usage of pesticides and fertilizers, seed coating agentshave gained popularity. This study employs single-factor and multi-index orthogonal experimental design ... To mitigate the wastage of seed resources and reduce the usage of pesticides and fertilizers, seed coating agentshave gained popularity. This study employs single-factor and multi-index orthogonal experimental design methodsto investigate the seed coating formula and physical properties of Tartary buckwheat. The specific effects ofeach component on Tartary buckwheat seed germination are analyzed. The findings reveal that the seed coatingagent formulated with 1.5% polyvinyl alcohol, 0.15% sodium alginate, 0.2% op-10, 0.1% polyacrylamide, 8% colorant,3% ammonium sulfate, 1% potassium dihydrogen phosphate, and 0.15% carbendazim exhibits the mosteffective coating. It demonstrates optimal physical properties and promotes seed germination efficiently. The suspensionrate of this seed coating agent reaches 91.12%, with a mere 2.13% coating shedding rate and 2.5% coatingseed rot rate. Furthermore, it achieves a germination percentage of 99.17%, which is 20.84% higher than the lowestgroup. The germination potential and index are also significantly higher than the lowest group, with anincrease of 20.84% and 26.56%, respectively. Additionally, the vitality index is 553.08, a 15.75% increase comparedto the lowest group. The application of seed coating agents helps reduce seed resource loss, increase plant numbers,and ultimately enhance agricultural yields. This finding holds practical significance in agriculturalproduction. 展开更多
关键词 Tartary buckwheat seed coating agent FORMULA GERMINATION
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Alkali Tolerance of Concrete Internal Curing Agent Based on Sodium Carboxymethyl Starch
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作者 陈梅花 刘荣进 +3 位作者 CHEN Ping JING Daiyan WAN Dandan FU Siyuan 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第1期82-90,共9页
Internal curing agents (ICA) based on super absorbent polymer have poor alkali tolerance and reduce the early strength of concrete.An alkali tolerate internal curing agent (CAA-ICA) was designed and prepared by using ... Internal curing agents (ICA) based on super absorbent polymer have poor alkali tolerance and reduce the early strength of concrete.An alkali tolerate internal curing agent (CAA-ICA) was designed and prepared by using sodium carboxymethyl starch (CMS) with high hydrophilicity,acrylic acid (AA) containing anionic carboxylic group and acrylamide (AM) containing non-ionic amide group as the main raw materials.The results show that the ratio of CAA-ICA alkali absorption solution is higher than that existing ICA,which solves the low water absorption ratio of the ICA in alkali environment.The water absorption ratio of CAA-ICA in saturated Ca(OH)_(2) solution is 95.8 g·g^(-1),and the alkali tolerance coefficient is 3.4.The application of CAA-ICA in cement-based materials can increase the internal relative humidity and miniaturize the pore structure.The compressive strength of mortar increases up to 12.95%at 28 d,which provids a solution to overcome the reduction of the early strength. 展开更多
关键词 alkali tolerance sodium carboxymethyl starch internal curing agent compressive strength
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General anesthetic agents induce neurotoxicity through oligodendrocytes in the developing brain
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作者 Wen-Xin Hang Yan-Chang Yang +7 位作者 Yu-Han Hu Fu-Quan Fang Lang Wang Xing-Hua Qian Patrick M.McQuillan Hui Xiong Jian-Hang Leng Zhi-Yong Hu 《Zoological Research》 SCIE CSCD 2024年第3期691-703,共13页
General anesthetic agents can impact brain function through interactions with neurons and their effects on glial cells.Oligodendrocytes perform essential roles in the central nervous system,including myelin sheath for... General anesthetic agents can impact brain function through interactions with neurons and their effects on glial cells.Oligodendrocytes perform essential roles in the central nervous system,including myelin sheath formation,axonal metabolism,and neuroplasticity regulation.They are particularly vulnerable to the effects of general anesthetic agents resulting in impaired proliferation,differentiation,and apoptosis.Neurologists are increasingly interested in the effects of general anesthetic agents on oligodendrocytes.These agents not only act on the surface receptors of oligodendrocytes to elicit neuroinflammation through modulation of signaling pathways,but also disrupt metabolic processes and alter the expression of genes involved in oligodendrocyte development and function.In this review,we summarize the effects of general anesthetic agents on oligodendrocytes.We anticipate that future research will continue to explore these effects and develop strategies to decrease the incidence of adverse reactions associated with the use of general anesthetic agents. 展开更多
关键词 OLIGODENDROCYTES General anesthetic agents NEUROTOXICITY Central nervous system Perioperative neurocognitive disorders
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Effect of neutral polymeric bonding agent on tensile mechanical properties and damage evolution of NEPE propellant
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作者 M.Wubuliaisan Yanqing Wu +3 位作者 Xiao Hou Kun Yang Hongzheng Duan Xinmei Yin 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期357-367,共11页
Introducing Neutral Polymeric bonding agents(NPBA) into the Nitrate Ester Plasticized Polyether(NEPE)propellant could improve the adhesion between filler/matrix interface, thereby contributing to the development of ne... Introducing Neutral Polymeric bonding agents(NPBA) into the Nitrate Ester Plasticized Polyether(NEPE)propellant could improve the adhesion between filler/matrix interface, thereby contributing to the development of new generations of the NEPE propellant with better mechanical properties. Therefore,understanding the effects of NPBA on the deformation and damage evolution of the NEPE propellant is fundamental to material design and applications. This paper studies the uniaxial tensile and stress relaxation responses of the NEPE propellant with different amounts of NPBA. The damage evolution in terms of interface debonding is further investigated using a cohesive-zone model(CZM). Experimental results show that the initial modulus and strength of the NEPE propellant increase with the increasing amount of NPBA while the elongation decreases. Meanwhile, the relaxation rate slows down and a higher long-term equilibrium modulus is reached. Experimental and numerical analyses indicate that interface debonding and crack propagation along filler-matrix interface are the dominant damage mechanism for the samples with a low amount of NPBA, while damage localization and crack advancement through the matrix are predominant for the ones with a high amount of NPBA. Finally, crosslinking density tests and simulation results also show that the effect of the bonding agent is interfacial rather than due to the overall crosslinking density change of the binder. 展开更多
关键词 Solid propellant Bonding agent Mechanical properties Damage evolution Cohesive-zone model Interface debonding
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基于组合遗传算法的电力科技创新成果多agent集成仿真
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作者 张天毅 刘茹 《信息技术》 2024年第3期158-163,169,共7页
电力科技成果普遍交叉,为了降低集成电力科技创新成果耗时与能量损耗,研究基于组合遗传算法的电力科技创新成果多agent集成仿真。将底层数据库中电力科技创新资源经多种接口调配至关联库、综合评价以及专家评价三大agent模块,通过结合... 电力科技成果普遍交叉,为了降低集成电力科技创新成果耗时与能量损耗,研究基于组合遗传算法的电力科技创新成果多agent集成仿真。将底层数据库中电力科技创新资源经多种接口调配至关联库、综合评价以及专家评价三大agent模块,通过结合遗传算法与蚁群算法优点的组合遗传算法,优化解决多agent集成任务分配问题,实现电力科技创新成果高效集成。实验表明,该算法的寻优能力高、求解速度快;可规范化、结构化地集成电力科技创新成果信息;具有耗时少、能量损耗低优势。为科技创新和成果转化提供新思路。 展开更多
关键词 组合遗传算法 电力科技 agent集成仿真 任务分配
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Preparation and performance evaluation of the slickwater using novel polymeric drag reducing agent with high temperature and shear resistance ability
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作者 Ming-Wei Zhao Zhen-Feng Ma +5 位作者 Cai-Li Dai WeiWu Yong-Quan Sun Xu-Guang Song Yun-Long Cheng Xiang-Yu Wang 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期1113-1121,共9页
Slickwater fracturing fluids are widely used in the development of unconventional oil and gas resources due to the advantages of low cost,low formation damage and high drag reduction performance.However,their performa... Slickwater fracturing fluids are widely used in the development of unconventional oil and gas resources due to the advantages of low cost,low formation damage and high drag reduction performance.However,their performance is severely affected at high temperatures.Drag reducing agent is the key to determine the drag reducing performance of slickwater.In this work,in order to further improve the temperature resistance of slickwater,a temperature-resistant polymeric drag reducing agent(PDRA)was synthesized and used as the basis for preparing the temperature-resistant slickwater.The slickwater system was prepared with the compositions of 0.2 wt%PDRA,0.05 wt%drainage aid nonylphenol polyoxyethylene ether phosphate(NPEP)and 0.5 wt%anti-expansion agent polyepichlorohydrindimethylamine(PDM).The drag reduction ability,rheology properties,temperature and shear resistance ability,and core damage property of slickwater were systematically studied and evaluated.In contrast to on-site drag reducing agent(DRA)and HPAM,the temperature-resistant slickwater demonstrates enhanced drag reduction efficacy at 90℃,exhibiting superior temperature and shear resistance ability.Notably,the drag reduction retention rate for the slickwater achieved an impressive 90.52%after a 30-min shearing period.Additionally,the core damage is only 5.53%.We expect that this study can broaden the application of slickwater in high-temperature reservoirs and provide a theoretical basis for field applications. 展开更多
关键词 Unconventional resources Polymeric drag reducing agent Slickwater High drag reduction rate Temperature resistance
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Effects of virtual agents on interaction efficiency and environmental immersion in MR environments
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作者 Yihua BAO Jie GUO +2 位作者 Dongdong WENG Yue LIU Zeyu TIAN 《虚拟现实与智能硬件(中英文)》 EI 2024年第2期169-179,共11页
Background Physical entity interactions in mixed reality(MR)environments aim to harness human capabilities in manipulating physical objects,thereby enhancing virtual environment(VEs)functionality.In MR,a common strate... Background Physical entity interactions in mixed reality(MR)environments aim to harness human capabilities in manipulating physical objects,thereby enhancing virtual environment(VEs)functionality.In MR,a common strategy is to use virtual agents as substitutes for physical entities,balancing interaction efficiency with environmental immersion.However,the impact of virtual agent size and form on interaction performance remains unclear.Methods Two experiments were conducted to explore how virtual agent size and form affect interaction performance,immersion,and preference in MR environments.The first experiment assessed five virtual agent sizes(25%,50%,75%,100%,and 125%of physical size).The second experiment tested four types of frames(no frame,consistent frame,half frame,and surrounding frame)across all agent sizes.Participants,utilizing a head mounted display,performed tasks involving moving cups,typing words,and using a mouse.They completed questionnaires assessing aspects such as the virtual environment effects,interaction effects,collision concerns,and preferences.Results Results from the first experiment revealed that agents matching physical object size produced the best overall performance.The second experiment demonstrated that consistent framing notably enhances interaction accuracy and speed but reduces immersion.To balance efficiency and immersion,frameless agents matching physical object sizes were deemed optimal.Conclusions Virtual agents matching physical entity sizes enhance user experience and interaction performance.Conversely,familiar frames from 2D interfaces detrimentally affect interaction and immersion in virtual spaces.This study provides valuable insights for the future development of MR systems. 展开更多
关键词 Mixed reality Virtual agents Interaction performance Environmental immersion Virtual environments
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