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Induced neural stem cells regulate microglial activation through Akt-mediated upregulation of CXCR4 and Crry in a mouse model of closed head injury

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Neural Regeneration Research 2025年第5期20卷 1416-1430页

作者： Mou Gao Qin Dong Dan Zou zhijun Yang Lili Guo Ruxiang xu Department of Neurosurgery Sichuan Academy of Medical Sciences and Sichuan Provincial People’s HospitalSchool of MedicineUniversity of Electronic Science and Technology of ChinaChengduSichuan ProvinceChina Department of Neurosurgery Chinese PLA General HospitalBeijingChina Department of Neurology Fu Xing HospitalCapital Medical UniversityBeijingChina

Microglial activation that occurs rapidly after closed head injury may play important and complex roles in neuroinflammation-associated neuronal damage and *** previously reported that induced neural stem cells can modulate the behavior of activated microglia via CXCL12/CXCR4 signaling,influencing their activation such that they can promote neurological ***,the mechanism of CXCR4 upregulation in induced neural stem cells remains *** this study,we found that nuclear factor-κB activation induced by closed head injury mouse serum in microglia promoted CXCL12 and tumor necrosis factor-αexpression but suppressed insulin-like growth factor-1 ***,recombinant complement receptor 2-conjugated Crry(CR2-Crry)reduced the effects of closed head injury mouse serum-induced nuclear factor-κB activation in microglia and the levels of activated microglia,CXCL12,and tumor necrosis factor-α.Additionally,we observed that,in response to stimulation(including stimulation by CXCL12 secreted by activated microglia),CXCR4 and Crry levels can be upregulated in induced neural stem cells via the interplay among CXCL12/CXCR4,Crry,and Akt signaling to modulate microglial *** agreement with these in vitro experimental results,we found that Akt activation enhanced the immunoregulatory effects of induced neural stem cell grafts on microglial activation,leading to the promotion of neurological recovery via insulin-like growth factor-1 secretion and the neuroprotective effects of induced neural stem cell grafts through CXCR4 and Crry upregulation in the injured cortices of closed head injury ***,these beneficial effects of Akt activation in induced neural stem cells were positively correlated with the therapeutic effects of induced neural stem cells on neuronal injury,cerebral edema,and neurological disorders post–closed head *** conclusion,our findings reveal that Akt activation may enhance the immunoregulatory effects of induced neura

关键词： Akt signaling cerebral edema closed head injury Crry CXCR4 induced neural stem cell microglia neuroinflammation

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PDA桩基检测技术的应用与评价

石油工程建设 1995年第2期21卷 9-14页

作者：徐至钧中外合资济南恒泉房地产开发有限公司山东省济南市250014

桩基工程动力检测是我国目前应用较广的一种桩基非破损动力检验方法。动测法（又称锤击贯入试桩法）试桩费用一般仅为静载试桩费用的1／2～1／3，而且试验和分析法简单易行，试验结果直观可靠。本文在介绍PDA桩基检测技术的检测设备、... 详细信息

桩基工程动力检测是我国目前应用较广的一种桩基非破损动力检验方法。动测法（又称锤击贯入试桩法）试桩费用一般仅为静载试桩费用的1／2～1／3，而且试验和分析法简单易行，试验结果直观可靠。本文在介绍PDA桩基检测技术的检测设备、测试方法和两种分析方法的基础上，结合工程实例和数据对该技术予以评价。

关键词：桩基础检测试桩基础高应变动力

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无粘结预应力混凝土的应用与前景

石油工程建设 1996年第5期22卷 9-15页

作者：徐志钧中外合资北京恒富房地产开发公司北京市丰台区100071

本文综述“八五”重点科技推广项目“无粘结预应力混凝土技术”的应用范例和推广前景，针对其“后张法”施工的工艺特点，结合JGJ／T92－93《无粘结预应力混凝土结构技术规程》，介绍构件的预应力计算、锚具配置、构造特点和混凝土浇筑... 详细信息

本文综述“八五”重点科技推广项目“无粘结预应力混凝土技术”的应用范例和推广前景，针对其“后张法”施工的工艺特点，结合JGJ／T92－93《无粘结预应力混凝土结构技术规程》，介绍构件的预应力计算、锚具配置、构造特点和混凝土浇筑的施工工艺，并对预应力筋的材料选用、处理和铺放以及现场浇筑施工、张拉设备的配备提供了可资借鉴的经验。

关键词：钢筋混凝土预应力受力分析钢丝

基于六轴多旋翼飞行器的赤眼蜂投放系统设计与试验

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农业机械学报 2016年第1期47卷 1-7页

作者：徐东甫白越宫勋续志军中国科学院长春光学精密机械与物理研究所长春130033 中国科学院大学北京100039

为更好地进行农作物病虫害防治,结合农业无人机和生物防治,设计了一种基于Hex-Rotor飞行器的赤眼蜂投放系统,实现赤眼蜂自主投放功能。首先,使用共轴双桨和旋翼系统的倾斜配置,对6轴多旋翼飞行器结构进行了改进,提高了系统的冗余性和可... 详细信息

为更好地进行农作物病虫害防治,结合农业无人机和生物防治,设计了一种基于Hex-Rotor飞行器的赤眼蜂投放系统,实现赤眼蜂自主投放功能。首先,使用共轴双桨和旋翼系统的倾斜配置,对6轴多旋翼飞行器结构进行了改进,提高了系统的冗余性和可靠性,整个系统满载9 kg,以10 m/s的速度可飞行超过20 min;然后,利用带有扩张状态观测器和快速微分器的反步控制算法,使系统在投放干扰和外部风扰共同作用下,能够很好地完成轨迹跟踪飞行任务。最后,设计了专用的赤眼蜂投放装置,配合GPS和Google earth地图,实现赤眼蜂自主投放功能。在实际试验中,投放系统投放速度超过9 700 m2/min,飞行投放覆盖率100%,赤眼蜂孵化率75.81%。试验证明,该系统可以稳定可靠地完成赤眼蜂的投放工作,投放效率和经济效益方面表现良好,可以实现无人机自主生物防治。

关键词：生物防治无人飞行器赤眼蜂自主投放系统

An Intelligent Framework for Resilience Recovery of FANETs with Spatio-Temporal Aggregation and Multi-Head Attention Mechanism

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Computers, Materials & Continua 2024年第5期79卷 2375-2398页

作者： zhijun Guo Yun Sun YingWang Chaoqi Fu Jilong Zhong Air Traffic Control and Navigation College Air Force Engineering UniversityXi’an710000China Institute of Systems Engineering Academy of Military ScienceBeijing100101China Equipment Management and UAV Engineering College Air Force Engineering UniversityXi’an710038China Defense Innovation Institute Academy of Military ScienceBeijing100071China

Due to the time-varying topology and possible disturbances in a conflict environment,it is still challenging to maintain the mission performance of flying Ad hoc networks(FANET),which limits the application of Unmanned Aerial Vehicle(UAV)swarms in harsh *** paper proposes an intelligent framework to quickly recover the cooperative coveragemission by aggregating the historical spatio-temporal network with the attention *** mission resilience metric is introduced in conjunction with connectivity and coverage status information to simplify the optimization model.A spatio-temporal node pooling method is proposed to ensure all node location features can be updated after destruction by capturing the temporal network *** with the corresponding Laplacian matrix as the hyperparameter,a recovery algorithm based on the multi-head attention graph network is designed to achieve rapid *** results showed that the proposed framework can facilitate rapid recovery of the connectivity and coverage more effectively compared to the existing *** results demonstrate that the average connectivity and coverage results is improved by 17.92%and 16.96%,respectively compared with the state-of-the-art ***,by the ablation study,the contributions of each different improvement are *** proposed model can be used to support resilient network design for real-time mission execution.

关键词： Resilience cooperative mission FANET spatio-temporal node pooling multi-head attention graph network

Anti-Spoofing:Integrated Information Authentication of BeiDou-ⅡCivil Navigation Message

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China Communications 2024年第9期21卷 242-261页

作者： Wu zhijun Liang Cheng Zhang Yun Liu Rusen Yue Meng School of Safety Science and Engineering Civil Aviation University of ChinaTianjin 300300China School of Electronic Information and Automation Civil Aviation University of ChinaTianjin 300300China Dalian Air Traffic Management Station of Civil Aviation of China Dalian 116000China

The BeiDou-Ⅱcivil navigation message(BDⅡ-CNAV)is transmitted in an open environment and no information integrity protection measures are ***,the BDⅡ-CNAV faces the threat of spoofing attacks,which can lead to wrong location reports and time *** order to deal with this threat,we proposed a scheme of anti-spoofing for BDⅡ-CNAV based on integrated information *** scheme generates two type authentication information,one is authentication code information(ACI),which is applied to confirm the authenticity and reliability of satellite time information,and the other is signature information,which is used to authenticate the integrity of satellite location information and other *** authentication information is designed to embed into the reserved bits in BDⅡ-CNAV without changing the frame *** order to avoid authentication failure caused by public key error or key error,the key or public key prompt information(KPKPI)are designed to remind the receiver to update both keys in *** results indicate that the scheme can successfully detect spoofing attacks,and the authentication delay is less than 1%of the transmission delay,which meets the requirements of BDⅡ-CNAV information authentication.

关键词： anti-spoofing authentication BeiDou-II civil navigation message(BDII-CNAV) signature spoofing attack

BDSec:Security Authentication Protocol for BeiDou-Ⅱ Civil Navigation Message

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China Communications 2024年第6期21卷 206-218页

作者： Wu zhijun Zhang Yuan Yang Yiming Wang Peng Yue Meng School of Safety Science and Engineering Civil Aviation University of ChinaTianjin 300300China School of Electronic Information and Automation Civil Aviation University of ChinaTianjin 300300China

Due to the lack of authentication mechanism in BeiDou navigation satellite system(BDS),BD-Ⅱ civil navigation message(BDⅡ-CNAV) are vulnerable to spoofing attack and replay *** solve this problem,we present a security authentication protocol,called as BDSec,which is designed by using China’s cryptography Shangyong Mima(SM) series algorithms,such as SM2/4/9 and Zu Chongzhi(ZUC)*** BDSec protocol,both of BDⅡ-CNAV and signature information are encrypted using the SM4 algorithm(Symmetric encryption mechanism).The encrypted result is used as the subject authentication *** protocol applies SM9 algorithm(Identity-based cryptography mechanism) to protect the integrity of the BDⅡ-CNAV,adopts the SM2 algorithm(Public key cryptosystem) to guarantee the confidentiality of the important session information,and uses the ZUC algorithm(Encryption and integrity algorithm) to verify the integrity of the message authentication serial number and initial information and the information in authentication initialization sub-protocol *** results of the SVO logic reasoning and performance analysis show that BDSec protocol meets security requirements for the dual user identity authentication in BDS and can realize the security authentication of BDⅡ-CNAV.

关键词： BDII civil navigation messages(BDIICNAV) BeiDou navigation satellite system(BDS) identity-based cryptography mechanism navigation message authentication protocol(BDSec)

Optimal Design and Experimental Study of Tightly Coupled SCR Mixers for Diesel Engines

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Energy Engineering 2024年第10期121卷 2893-2906页

作者： Jianhua Zhang Wen Sun zhijun Li State Key Laboratory of Engines Tianjin UnivesityTianjin300072China Weichai Power Emission Solutions Technology Co. Ltd.Weifang261061China School of Energy and Power Engineering Shandong UniversityJinan250061China

Two types of tightly coupled Selective Catalytic Reduction(SCR)mixers were designed in this study,namely Mixer 1 integrated with an SCR catalyst and Mixer 2 arranged *** Fluid Dynamics(CFD)software was utilized to model the gas flow,spraying,and pyrolysis reaction of the aqueous urea solution in the tightly coupled SCR *** parameters of gas flow velocity uniformity and ammonia distribution uniformity were simulated and calculated for both Mixer 1 and Mixer 2 in the tightly coupled SCR system to compare their advantages and *** simulation results indicated that Mixer 1 exhibited a gas velocity uniformity of 0.972 and an ammonia distribution uniformity of 0.817,whereas Mixer 2 demonstrated a gas velocity uniformity of 0.988 and an ammonia distribution uniformity of *** 2 performed better in the simulation ***,a 3D-printed prototype of Mixer 2 was manufactured and installed on an engine test bench to investigate ammonia distribution uniformity and NOX conversion *** experimental investigations yielded the following findings:1)The ammonia distribution uniformity of Mixer 2 was measured as 0.976,which closely aligned with the simulation result of 0.964,with a deviation of 1.2%from the model calculations;2)As exhaust temperature increased,the ammonia distribution uniformity gradually improved,while an increase in exhaust flow rate resulted in a decrease in ammonia distribution uniformity;3)When utilizing Mixer 2,the NOX conversion efficiency reached 84.7%at an exhaust temperature of 200°C and 97.4%at 250°*** the exhaust temperature range of 300°C to 450°C,the NOX conversion efficiency remained above 98%.This study proposed two innovative mixer structures,conducted simulation analysis,and performed performance *** research outcomes indicated that the separately arranged Mixer 2 exhibited superior *** tightly coupled SCR systemequippedwith Mixer 2 achieved excellent levels

关键词： Tightly coupled SCR mixer ammonia distribution uniformity

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塔基础突发沉降的事故处理

石油工程建设 1995年第1期21卷 44-47页

作者：徐至钧中外合资济南恒泉房地产开发有限公司山东省济南市250014

某炼油厂高塔地基浸水后，造成大面积湿陷而引起基础突发沉降事故，本文报道经实测分析及时采取的处理措施和控制沉降的处理效果。

关键词：分馏塔汽提塔基础沉降地基炼油厂