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Investigating the Role of Antimalarial Treatment and Mosquito Nets in Malaria Transmission and Control through Mathematical Modeling
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作者 Azhar Iqbal Kashif Butt Tariq Ismaeel +4 位作者 Sara Khan Muhammad Imran Waheed Ahmad Ismail Abdulrashid Muhammad Sajid Riaz 《Computer Modeling in Engineering & Sciences》 2025年第9期3463-3492,共30页
Malaria is a significant global health challenge.This devastating disease continues to affect millions,especially in tropical regions.It is caused by Plasmodium parasites transmitted by female Anopheles mosquitoes.Thi... Malaria is a significant global health challenge.This devastating disease continues to affect millions,especially in tropical regions.It is caused by Plasmodium parasites transmitted by female Anopheles mosquitoes.This study introduces a nonlinear mathematical model for examining the transmission dynamics of malaria,incorporating both human and mosquito populations.We aim to identify the key factors driving the endemic spread of malaria,determine feasible solutions,and provide insights that lead to the development of effective prevention and management strategies.We derive the basic reproductive number employing the next-generation matrix approach and identify the disease-free and endemic equilibrium points.Stability analyses indicate that the disease-free equilibrium is locally and globally stable when the reproductive number is below one,whereas an endemic equilibrium persists when this threshold is exceeded.Sensitivity analysis identifies the most influential mosquito-related parameters,particularly the bite rate and mosquito mortality,in controlling the spread of malaria.Furthermore,we extend our model to include a treatment compartment and three disease-preventive control variables such as antimalaria drug treatments,use of larvicides,and the use of insecticide-treated mosquito nets for optimal control analysis.The results show that optimal use of mosquito nets,use of larvicides for mosquito population control,and treatment can lower the basic reproduction number and control malaria transmission with minimal intervention costs.The analysis of disease control strategies and findings offers valuable information for policymakers in designing cost-effective strategies to combat malaria. 展开更多
关键词 MALARIA mathematical modeling optimal control mosquito nets anti-malaria drugs stability and sensitivity analysis
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Social Safety Nets and Their Effectiveness in Poverty Alleviation:Evidence from Banadir Region,Somalia
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作者 Elmi Hassan Samatar 《Journal of Environmental & Earth Sciences》 2025年第3期77-87,共11页
The paper primarily focuses on social safety nets and their effectiveness in poverty alleviation.Social Safety Net(SSN)programs pertain to social service initiatives aimed at providing temporary assistance to individu... The paper primarily focuses on social safety nets and their effectiveness in poverty alleviation.Social Safety Net(SSN)programs pertain to social service initiatives aimed at providing temporary assistance to individuals or groups facing vulnerabilities or unexpected hardships,such as those with lower incomes.Poverty poses a significant obstacle to the progress of social development,and its impacts are worsened by various factors including insecurity,frequent flooding,and droughts in Somalia.A total of 342 households in the Banadir region of Somalia were interviewed for the social safety nets(SSN)study.Data collection in the study was facilitated through the utilization of Kobo Toolbox,while the data analysis was conducted using EViews v.12.The results obtained from the ADP and PP tests indicated that all variables exhibited stationarity at the level.The Impact Assessment(IA)reveals a positive correlation with Household Income and Poverty Indices(HIPI),suggesting a risk of dependency without a strategic exit strategy,potentially leading to a 26%increase in poverty levels.A well-executed Program Implementation and Design(PID)can result in a 33%increase in income and poverty indices.Recipients perceive the Social Safety Net(PSSN)as reducing poverty and increasing income by 11%.Therefore,the study recommends integrating beneficiaries into the urban economy through sustainable livelihood options.Finally,the Somali government should prioritize the implementation of sustainable livelihood programs to mitigate dependency and alleviate poverty among SSN beneficiaries. 展开更多
关键词 Social Safety nets(SSNs) Poverty Alleviation Household Income Agriculture Income Generation Activities(IGAs) Sustainable Livelihoods Banadir Region SOMALIA
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Modeling and performance analysis of GNSS-based train positioning system with colored petri nets
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作者 Shuting Chen Daohua Wu +1 位作者 Jiang Liu Siqi Wang 《High-Speed Railway》 2025年第3期175-184,共10页
Global Navigation Satellite System(GNSS)-based continuous and accurate train positioning is one of the key technologies for advanced train operations such as train virtual coupling.However,GNSS-based train positioning... Global Navigation Satellite System(GNSS)-based continuous and accurate train positioning is one of the key technologies for advanced train operations such as train virtual coupling.However,GNSS-based train positioning faces significant challenges in real-world scenarios due to environmental complexities and signal interferences.Considering this issue,this paper presents an approach for modeling and performance analysis of GNSS-based train positioning systems using Colored Petri Nets(CPNs).By systematically modeling the GNSS signal reception and processing process,the performance of the positioning system under various environment scenarios is evaluated.The system model integrates three types of interference signals(i.e.,Amplitude Modulation(AM)signals,Frequency Modulation(FM)signals,and pulse signals)while incorporating environmental factors such as terrain obstructions and tunnel shielding.Additionally,the Extended Kalman Filter(EKF)algorithm is employed to process GNSS observation data,providing accurate train position estimations.The simulation results demonstrate that signal interferences and complex environmental conditions significantly affect the GNSS-based positioning accuracy.This study offers a comprehensive framework for evaluating the performance of GNSS-based train positioning systems in different scenarios,highlighting critical factors that influence positioning accuracy and stability. 展开更多
关键词 GNSS-based train positioning Positioning performance Environment scenario GNSS signal interference Colored petri nets
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狼疮性肾炎患者血清NETs、TWEAK、外周血CD4^(+)T/CD8^(+)T比例与疾病活动度及肾脏预后的关系 被引量:3
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作者 钟凤梅 易娟 +2 位作者 郭昕 王菲 夏成云 《现代生物医学进展》 CAS 2024年第1期194-200,共7页
目的:探讨狼疮性肾炎(LN)患者血清中性粒细胞胞外诱捕网(NETs)、肿瘤坏死因子样凋亡微弱诱导剂(TWEAK)、外周血分化簇(CD)4^(+)T/CD8^(+)T比例与疾病活动度及肾脏预后的关系。方法:选取2021年8月~2022年8月川北医学院附属医院肾内科收治... 目的:探讨狼疮性肾炎(LN)患者血清中性粒细胞胞外诱捕网(NETs)、肿瘤坏死因子样凋亡微弱诱导剂(TWEAK)、外周血分化簇(CD)4^(+)T/CD8^(+)T比例与疾病活动度及肾脏预后的关系。方法:选取2021年8月~2022年8月川北医学院附属医院肾内科收治的LN患者137例(LN组),根据系统性红斑狼疮疾病活动指数(SLEDAI)-2000评分分为轻度活动组(52例)、中度活动组(45例)、重度活动组(40例)。随访1年,根据肾脏相关终点事件发生情况分为预后不良组(43例)和预后良好组(94例),另选取同期76名体检健康志愿者(对照组)。采用酶联免疫吸附法检测血清NETs、TWEAK水平,流式细胞术检测外周血CD4^(+)T/CD8^(+)T比例。Spearman相关性分析LN患者血清NETs、TWEAK和外周血CD4^(+)T/CD8^(+)T与SLEDAI-2000评分的相关性,多因素Logistic回归分析LN患者预后不良的因素,受试者工作特征曲线分析血清NETs、TWEAK和外周血CD4^(+)T/CD8^(+)T对LN患者预后不良的预测价值。结果:与对照组比较,LN组血清NETs、TWEAK水平升高,外周血CD4^(+)T/CD8^(+)T降低(P<0.05)。轻度活动组、中度活动组、重度活动组血清NETs、TWEAK依次升高,外周血CD4^(+)T/CD8^(+)T依次降低(P<0.05)。LN患者SLEDAI-2000评分与血清NETs、TWEAK呈正相关,与外周血CD4^(+)T/CD8^(+)T呈负相关(P<0.05)。慢性肾脏病分期4期、SLEDAI-2000评分升高、NETs升高、TWEAK升高为LN患者预后不良的独立危险因素,估算肾小球滤过率升高、CD4^(+)T/CD8^(+)T升高为独立保护因素(P<0.05)。血清NETs、TWEAK和外周血CD4^(+)T/CD8^(+)T联合预测LN患者预后不良的曲线下面积为0.943,大于血清NETs、TWEAK和外周血CD4^(+)T/CD8^(+)T单独预测的0.790、0.788、0.799(P<0.05)。结论:LN患者血清NETs、TWEAK水平升高,外周血CD4^(+)T/CD8^(+)T降低,与疾病活动度及肾脏预后不良密切相关,血清NETs、TWEAK联合外周血CD4^(+)T/CD8^(+)T预测LN患者肾脏预后的价值较高。 展开更多
关键词 狼疮性肾炎 nets TWEAK CD4+T/CD8+T 疾病活动度 肾脏预后
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Medical ozone alleviates acute lung injury by enhancing phagocytosis targeting NETs via AMPK/SR-A1 axis 被引量:3
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作者 Chenxiao Yan Yong Zhang +10 位作者 Lai Jin Xiaojie Liu Xuexian Zhu Qifeng Li Yu Wang Liang Hu Xueming He Hongguang Bao Xia Zhu Qian Wang Wen-Tao Liu 《Journal of Biomedical Research》 CAS CSCD 2024年第6期569-584,共16页
Acute lung injury(ALI)linked to sepsis has a high mortality rate,with limited treatment options available.In recent studies,medical ozone has shown the potential to alleviate inflammation and infection.Here,we aimed t... Acute lung injury(ALI)linked to sepsis has a high mortality rate,with limited treatment options available.In recent studies,medical ozone has shown the potential to alleviate inflammation and infection.Here,we aimed to evaluate therapeutic potential of medical ozone in a mouse model of the sepsis-induced ALI by measuring behavioral assessments,lung function,and blood flow.Protein levels were quantified by Western blotting.In vitro,we performed experiments on bone marrow-derived macrophages(BMDMs)to investigate the effect of adenosine monophosphate(AMP)-activated protein kinase(AMPK)inhibitors and agonists on their phagocytic activity.The results showed that medical ozone significantly improved the survival rate,ameliorated lung injury,and enhanced lung function and limb microcirculation in mice with ALI.Notably,medical ozone inhibited the formation of neutrophil extracellular traps(NETs),a crucial factor in the ALI development.Additionally,medical ozone counteracted the elevated levels of tissue factor,matrix metalloproteinase-9,and interleukin-1β.In the ALI mice,the effects of ozone were abolished,and BMDMs showed an impaired capacity to engulf NETs following the Sr-a1 knockout.Under normal physiological conditions,the administration of an AMPK antagonist showed similar effects on the Sr-a1 knockout,significantly inhibiting the phagocytosis of NETs by BMDMs.In contrast,AMPK agonists enhanced this phagocytic process.In conclusion,medical ozone may alleviate the sepsis-induced lung injury through the AMPK/SR-A1 pathway,thereby enhancing the phagocytosis of NETs by macrophages. 展开更多
关键词 SR-A1 nets ALI PHAGOCYTOSIS ozone therapy
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NETs介导类风湿性关节炎并发动脉粥样硬化及中药干预研究进展 被引量:1
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作者 李月兴 陈波洋 +3 位作者 陈帅 赵玲婕 晏一平 陈云志 《中药药理与临床》 CAS CSCD 北大核心 2024年第6期123-128,共6页
流行病学数据表明,心血管并发症困扰着近半数类风湿性关节炎(Rheumatoid arthritis,RA)患者,是RA患者的主要死亡原因。这可能与RA同动脉粥样硬化具有相似的病理特征,致使该病患者动脉粥样硬化发生率增加有关。中性粒细胞胞外诱捕网作为... 流行病学数据表明,心血管并发症困扰着近半数类风湿性关节炎(Rheumatoid arthritis,RA)患者,是RA患者的主要死亡原因。这可能与RA同动脉粥样硬化具有相似的病理特征,致使该病患者动脉粥样硬化发生率增加有关。中性粒细胞胞外诱捕网作为一把双刃剑,一方面能捕获病原体限制疾病发展,一方面也可成为致病因素加重病情,其介导的炎症反应是RA、动脉粥样硬化、血栓等疾病的共同特点。研究表明,中医药可通过多种途径对动脉粥样硬化产生积极作用,相关中药通过调控中性粒细胞胞外诱捕网治疗RA也收效甚佳。对此,笔者提出猜想,中医药或可通过干预中性粒细胞胞外诱捕网改善RA并发动脉粥样硬化。 展开更多
关键词 nets 动脉粥样硬化 类风湿性关节炎 中医药
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基于Deep Belief Nets的中文名实体关系抽取 被引量:73
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作者 陈宇 郑德权 赵铁军 《软件学报》 EI CSCD 北大核心 2012年第10期2572-2585,共14页
关系抽取是信息抽取的一项子任务,用以识别文本中实体之间的语义关系.提出一种利用DBN(deepbelief nets)模型进行基于特征的实体关系抽取方法,该模型是由多层无监督的RBM(restricted Boltzmann machine)网络和一层有监督的BP(back-propa... 关系抽取是信息抽取的一项子任务,用以识别文本中实体之间的语义关系.提出一种利用DBN(deepbelief nets)模型进行基于特征的实体关系抽取方法,该模型是由多层无监督的RBM(restricted Boltzmann machine)网络和一层有监督的BP(back-propagation)网络组成的神经网络分类器.RBM网络以确保特征向量映射达到最优,最后一层BP网络分类RBM网络的输出特征向量,从而训练实体关系分类器.在ACE04语料上进行的相关测试,一方面证明了字特征比词特征更适用于中文关系抽取任务;另一方面设计了3组不同的实验,分别使用正确的实体类别信息、通过实体类型分类器得到实体类型信息和不使用实体类型信息,用以比较实体类型信息对关系抽取效果的影响.实验结果表明,DBN非常适用于基于高维空间特征的信息抽取任务,获得的效果比SVM和反向传播网络更好. 展开更多
关键词 DBN(deep BELIEF nets) 神经网络 关系抽取 深层网络 字特征
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基于不完备信息系统规则提取和Petri Nets的电力变压器故障诊断 被引量:11
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作者 荣雅君 赵杰 +2 位作者 王健 吴闻婧 葛葆华 《电力系统保护与控制》 EI CSCD 北大核心 2009年第18期1-4,10,共5页
鉴于电力变压器故障信息具有不完备性及复杂性,将不完备信息系统规则的提取与Petri Nets(PNs)有机结合在一起进行变压器故障诊断。利用不完备信息规则提取对信息表进行知识的简化与故障特征的压缩,获得最小诊断规则,并利用此规则建造PN... 鉴于电力变压器故障信息具有不完备性及复杂性,将不完备信息系统规则的提取与Petri Nets(PNs)有机结合在一起进行变压器故障诊断。利用不完备信息规则提取对信息表进行知识的简化与故障特征的压缩,获得最小诊断规则,并利用此规则建造PNs的模型。同时利用PNs实现并行推理,对变压器进行快速分析。故障实例分析表明,文中所提出的智能方法具有准确性,有效性。 展开更多
关键词 PETRI nets 电力变压器 故障诊断 规则提取 不完备信息系统
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Intrusion detection model based on deep belief nets 被引量:6
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作者 高妮 高岭 +2 位作者 贺毅岳 高全力 任杰 《Journal of Southeast University(English Edition)》 EI CAS 2015年第3期339-346,共8页
This paper focuses on the intrusion classification of huge amounts of data in a network intrusion detection system. An intrusion detection model based on deep belief nets (DBN) is proposed to conduct intrusion detec... This paper focuses on the intrusion classification of huge amounts of data in a network intrusion detection system. An intrusion detection model based on deep belief nets (DBN) is proposed to conduct intrusion detection,and the principles regarding DBN are discussed.The DBN is composed of a multiple unsupervised restricted Boltzmann machine (RBM) and a supervised back propagation (BP)network.First,the DBN in the proposed model is pre-trained in a fast and greedy way,and each RBM is trained by the contrastive divergence algorithm.Secondly,the whole network is fine-tuned by the supervised BP algorithm,which is employed for classifying the low-dimensional features of the intrusion data generated by the last RBM layer simultaneously.The experimental results on the KDD CUP 1999 dataset demonstrate that the DBN using the RBM network with three or more layers outperforms the self-organizing maps (SOM)and neural network (NN)in intrusion classification.Therefore,the DBN is an efficient approach for intrusion detection in high-dimensional space. 展开更多
关键词 intrusion detection deep belief nets restricted Boltzmann machine deep learning
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狼疮定联合地塞米松对SLE患者外周血中性粒细胞NETs生成的影响 被引量:4
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作者 汪梅姣 谢志军 +2 位作者 黄琳 温成平 李海昌 《中华中医药杂志》 CAS CSCD 北大核心 2021年第12期7314-7318,共5页
目的:预测狼疮定对中性粒细胞的作用靶点;研究狼疮定及狼疮定联合地塞米松(DXM)对佛波酯(PMA)诱导的系统性红斑狼疮(SLE)患者外周血中性粒细胞(PMN)中性粒细胞胞外诱捕网(NETs)生成的影响。方法:运用网络药理学对狼疮定进行靶点及功能预... 目的:预测狼疮定对中性粒细胞的作用靶点;研究狼疮定及狼疮定联合地塞米松(DXM)对佛波酯(PMA)诱导的系统性红斑狼疮(SLE)患者外周血中性粒细胞(PMN)中性粒细胞胞外诱捕网(NETs)生成的影响。方法:运用网络药理学对狼疮定进行靶点及功能预测;分离PMN并使用流式细胞术检测PMN纯度,激光共聚焦显微镜观察NETs生成情况,ELISA法检测血浆和细胞培养上清液中髓过氧化物酶(MPO)、中性粒细胞弹性蛋白酶(NE)和抗菌肽(LL37)含量。结果:网络药理学功能预测显示,狼疮定与中性粒细胞迁移、趋化功能显著相关。SLE患者血浆中MPO、NE、LL37含量均显著高于健康人(P<0.01)。LCD+DXM组PMN细胞核伸展,组蛋白H3解凝聚,MPO增多,NETs未形成或生成较少。与PMA组比较,LCD+DXM组培养上清液中LL37含量显著减少(P<0.01)。结论:狼疮定可调控中性粒细胞迁移、趋化功能,狼疮定联合地塞米松体外可减少NETs生成,从而抑制SLE发病。 展开更多
关键词 系统性红斑狼疮 中性粒细胞 nets 狼疮定 地塞米松
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NETs在自身免疫性疾病发病机制中的作用研究进展 被引量:4
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作者 肖芳 郑成云 +1 位作者 蒋卫东 陈丽 《中国免疫学杂志》 CAS CSCD 北大核心 2017年第5期781-783,787,共4页
中性粒细胞作为人体固有免疫系统的哨兵,在血液的非特异性细胞免疫系统中起着十分重要的作用,它们由骨髓分化发育成熟后,进入血液或组织,当微生物病原体特别是化脓性细菌入侵、炎症发生时,在多种炎症和细胞因子的介导下,它们便会被迅速... 中性粒细胞作为人体固有免疫系统的哨兵,在血液的非特异性细胞免疫系统中起着十分重要的作用,它们由骨髓分化发育成熟后,进入血液或组织,当微生物病原体特别是化脓性细菌入侵、炎症发生时,在多种炎症和细胞因子的介导下,它们便会被迅速招募并趋化至炎症部位,通过分泌细胞因子、脱颗粒和吞噬作用等杀灭并清除病原体。 展开更多
关键词 自身免疫性疾病 发病机制 nets 细胞免疫系统 微生物病原体 分泌细胞因子 中性粒细胞 化脓性细菌
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Resource Allocation Using Timed Petri Nets and Heuristic Search 被引量:3
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作者 张志明 王越 +2 位作者 陶然 阎飞 周思永 《Journal of Beijing Institute of Technology》 EI CAS 2000年第2期148-154,共7页
Traditional models for project management have not adequately incorporated a number of factors that are important for resource allocation. This paper proposed a unified timed Petri net model in which scheduling and pl... Traditional models for project management have not adequately incorporated a number of factors that are important for resource allocation. This paper proposed a unified timed Petri net model in which scheduling and planning were collectively carried out to take full advantages of the flexibility of the FMS. Through the lens of system theory, two types of resources were distinguished: major role and auxiliary role, and the major role was used to construct the FMS' Petri net. The method simplified the Petri net's construction and gave a clear flow chart for scheduling. Hence, the auxiliary resource allocation could be easily carried out according to the schedule, which was proposed by heuristic search algorithm. At last, the efficacy of the Petri net model for online scheduling in a resource constrained environment was discussed. 展开更多
关键词 heuristic search Petri nets resource allocation
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外周血cf-DNA/NETs水平与重症肺炎并发ARDS患者病情严重程度及预后的相关性 被引量:12
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作者 董照刚 郑喜胜 +2 位作者 赵聪源 魏超 周小超 《热带医学杂志》 CAS 2020年第11期1433-1437,共5页
目的探讨外周血游离DNA/中性粒细胞胞外诱捕网陷阱(cf-DNA/NETs)水平与重症肺炎并发急性呼吸窘迫综合征(ARDS)患者病情严重程度及预后的相关性。方法选取南阳市中心医院2016年8月-2018年4月收治重症肺炎并发ARDS组患者82例,同期重症肺... 目的探讨外周血游离DNA/中性粒细胞胞外诱捕网陷阱(cf-DNA/NETs)水平与重症肺炎并发急性呼吸窘迫综合征(ARDS)患者病情严重程度及预后的相关性。方法选取南阳市中心医院2016年8月-2018年4月收治重症肺炎并发ARDS组患者82例,同期重症肺炎组患者67例,及本院健康体检者82人为对照组,比较治疗前、入住本院ICU治疗24、48 h重症肺炎并发ARDS组患者、同期重症肺炎组患者及对照组的cf-DNA/NET水平、白细胞介素-6(IL-6)水平、白细胞计数(WBC)、急性生理学及慢性健康(APACHEⅡ)评分。用荧光染色法检测外周血中cf-DNA/NETs水平。分析cf-DNA/NETs水平、APACHEⅡ评分与预后的关系。结果治疗前,与对照组相比,重症肺炎组、重症肺炎并发ARDS组患者外周血cf-DNA/NETs水平、IL-6水平、WBC计数及APACHEⅡ评分升高,差异有统计学意义(P<0.05)。治疗后24、48 h,两组患者外周血cf-DNA/NETs水平、IL-6水平、WBC计数及APACHEⅡ评分组间和组内差异有统计学意义(P<0.05)。治疗48 h后,与存活组相比,死亡组重症肺炎并发ARDS患者血清cfDNA/NETs、IL-6水平、WBC计数、APACHEⅡ评分显著较高,差异有统计学意义(P<0.05)。重症肺炎并发ARDS患者外周血cf-DNA/NETs水平与IL-6、WBC计数、APACHEⅡ评分呈正相关(P<0.05)。Logistic分析显示,cf-DNA/NETs是重症肺炎并发ARDS患者不良预后危险因素(P<0.05)。结论外周血cf-DNA/NETs可能参与重症肺炎并发ARDS病情发展,cf-DNA/NETs高水平是重症肺炎并发ARDS患者不良预后危险因素。 展开更多
关键词 重症肺炎 急性呼吸窘迫综合征 nets cf-DNA
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基于粗糙集理论和Petri Nets的变压器故障诊断 被引量:2
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作者 荣雅君 赵杰 +1 位作者 王健 吴闻靖 《变压器》 北大核心 2008年第12期56-59,共4页
介绍了一种基于粗糙集理论和Petri Nets相结合的变压器故障诊断方法,并通过故障实例证实了该方法的准确性和高效性。
关键词 变压器 粗糙集 PETRI nets 故障诊断
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Structural Complexity Analysis of Information Systems Based on Petri Nets 被引量:3
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作者 王景光 甘仞初 《Journal of Beijing Institute of Technology》 EI CAS 1999年第4期416-423,共8页
Aim To present a quantitative method for structural complexity analysis and evaluation of information systems. Methods Based on Petri net modeling and analysis techniques and with the aid of mathematical tools in ge... Aim To present a quantitative method for structural complexity analysis and evaluation of information systems. Methods Based on Petri net modeling and analysis techniques and with the aid of mathematical tools in general net theory(GNT), a quantitative method for structure description and analysis of information systems was introduced. Results The structural complexity index and two related factors, i.e. element complexity factor and connection complexity factor were defined, and the relations between them and the parameters of the Petri net based model of the system were derived. Application example was presented. Conclusion The proposed method provides a theoretical basis for quantitative analysis and evaluation of the structural complexity and can be applied in the general planning and design processes of the information systems. 展开更多
关键词 information system Petri nets structural complexity element complexity factor connection complexity factor
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新发现的中性粒细胞杀菌途径NETs 被引量:2
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作者 谢东北 郝选明 《中国免疫学杂志》 CAS CSCD 北大核心 2008年第7期669-670,F0003,共3页
关键词 中性粒细胞 杀菌机制 nets NADPH氧化酶 吞噬小体 快速反应部队 感染部位 超氧阴离子
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基于Time Petri Nets的UML时序图分析 被引量:1
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作者 徐景辉 刘文海 张根度 《计算机工程》 EI CAS CSCD 北大核心 2005年第19期105-107,共3页
引入一种称为Clock的变迁,用来改进TPNs,讨论了如何将时序图转换为基于Clock变迁的TPNs,使这种TPNs能正确反映时序图的流程和时间约束。最后,利用普通Petri网的可达性分析技术对时序图模型进行了分析和验证。
关键词 UML时序图 TIME PETRI nets 可达性分析
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从新版NETS·T看教师教育技术能力建设的新发展 被引量:9
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作者 王奕标 《电化教育研究》 CSSCI 北大核心 2009年第10期115-120,共6页
2008年6月30日美国国际教育技术协会公布了新版的《美国教师国家教育技术标准》。以新版《美国教师教育技术标准》实施为契机,教育技术研究和教育技术能力建设将会迎来新的发展。本文阐述了新版标准的内容结构及其创新之处,并对教育技... 2008年6月30日美国国际教育技术协会公布了新版的《美国教师国家教育技术标准》。以新版《美国教师教育技术标准》实施为契机,教育技术研究和教育技术能力建设将会迎来新的发展。本文阐述了新版标准的内容结构及其创新之处,并对教育技术研究和教师教育技术能力建设的新发展进行探讨。 展开更多
关键词 nets·T 创新学习 教育技术能力 建设
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基于Petri Nets和遗传算法结合的配变变压器故障的恢复研究 被引量:2
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作者 孙雅明 宋轶博 《继电器》 CSCD 北大核心 2004年第15期14-18,58,共6页
在基于PetriNets(PN)模型的配电变电站的在线故障恢复研究中,重点研究了变压器的PN恢复处理模型与优化策略模块的结合:PN模型依据配变运行模式、非故障变压器容量对转移负载和过载的承受力来考虑恢复策略的求解操作;在甩负荷操作时,则... 在基于PetriNets(PN)模型的配电变电站的在线故障恢复研究中,重点研究了变压器的PN恢复处理模型与优化策略模块的结合:PN模型依据配变运行模式、非故障变压器容量对转移负载和过载的承受力来考虑恢复策略的求解操作;在甩负荷操作时,则按供电可靠性的原则对负荷重要性排序,按尽量少的操作次数、按流过母联功率最小作约束,构造有序优化约束目标的全局优化GA算法来完成。该文的变压器故障恢复方法,不仅保证了PN模型数学求解的快速优势,而且可克服单一PN模型恢复中优化处理和刻画动态特性的局限性。仿真结果表明研究方法是可行、有效的,具有较高的实用价值。 展开更多
关键词 配变变压器 故障恢复 遗传算法 PETRI nets 电力系统 供电可靠性
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