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A Radar Countermeasure Modeling Method Incorporating Cognitive Bias
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作者 Wang Rui Li Xiangyang +2 位作者 Wang Dong Ma Hongguang Zhang Zhili 《系统仿真学报》 北大核心 2025年第4期1090-1101,共12页
Cognitive bias,stemming from electronic measurement error and variability in human perception,exists in cognitive electronic warfare and affects the outcomes of conflicts.In this paper,the dynamic game approach is emp... Cognitive bias,stemming from electronic measurement error and variability in human perception,exists in cognitive electronic warfare and affects the outcomes of conflicts.In this paper,the dynamic game approach is employed to develop a model for cognitive bias induced by incomplete information and measurement errors in cognitive radar countermeasures.The payoffs for both parties are calculated using the radar's anti-jamming strategy matrix A and the jammer's jamming strategy matrix B.With perfect Bayesian equilibrium,a dynamic radar countermeasure model is established,and the impact of cognitive bias is analyzed.Drawing inspiration from the cognitive bias analysis method used in stock market trading,a cognitive bias model for cognitive radar countermeasures is introduced,and its correctness is mathematically proved.A gaming scenario involving the AN/SPY-1 radar and a smart jammer is set up to analyze the influence of cognitive bias on game outcomes.Simulation results validate the effectiveness of the proposed method. 展开更多
关键词 cognitive electronic warfare cognitive bias radar countermeasure dynamic game perfect Bayesian equilibrium
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Blind recognition of k/n rate convolutional encoders from noisy observation 被引量:13
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作者 Li Huang Wengu Chen +1 位作者 Enhong Chen Hong Chen 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第2期235-243,共9页
Blind recognition of convolutional codes is not only essential for cognitive radio, but also for non-cooperative context. This paper is dedicated to the blind identification of rate k/n convolutional encoders in a noi... Blind recognition of convolutional codes is not only essential for cognitive radio, but also for non-cooperative context. This paper is dedicated to the blind identification of rate k/n convolutional encoders in a noisy context based on Walsh-Hadamard transformation and block matrix (WHT-BM). The proposed algorithm constructs a system of noisy linear equations and utilizes all its coefficients to recover parity check matrix. It is able to make use of fault-tolerant feature of WHT, thus providing more accurate results and achieving better error performance in high raw bit error rate (BER) regions. Moreover, it is more computationally efficient with the use of the block matrix (BM) method. © 2017 Beijing Institute of Aerospace Information. 展开更多
关键词 cognitive radio CONVOLUTION Convolutional codes Error correction Hadamard matrices Hadamard transforms Linear transformations Mathematical transformations Matrix algebra Signal encoding
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基于Social Cognition粒子群算法多用户检测
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作者 许耀华 胡艳军 《无线电通信技术》 2006年第6期30-32,38,共4页
最优多用户检测方法具有最优性能,但复杂度高,利用优化算法求解可以降低实现复杂度。粒子群算法是一种简单有效的新型群智能优化算法,研究了一种Socialcognition模型简化粒子群算法,并应用于大用户量CDMA多用户检测问题,主要考虑降低算... 最优多用户检测方法具有最优性能,但复杂度高,利用优化算法求解可以降低实现复杂度。粒子群算法是一种简单有效的新型群智能优化算法,研究了一种Socialcognition模型简化粒子群算法,并应用于大用户量CDMA多用户检测问题,主要考虑降低算法复杂度,提高算法的实现效率。分析及仿真表明该方法在系统用户数量较大时具有较好性能。 展开更多
关键词 码分多址 多用户检测 离散粒子群优化算法 社会认知理论
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Automatic radar antenna scan type recognition based on limited penetrable visibility graph 被引量:2
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作者 LIU Songtao LEI Zhenshuo +1 位作者 GE Yang WEN Zhenming 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2021年第2期437-446,共10页
To address the problem of the weak anti-noise and macro-trend extraction abilities of the current methods for identifying radar antenna scan type,a recognition method for radar antenna scan types based on limited pene... To address the problem of the weak anti-noise and macro-trend extraction abilities of the current methods for identifying radar antenna scan type,a recognition method for radar antenna scan types based on limited penetrable visibility graph(LPVG)is proposed.Firstly,seven types of radar antenna scans are analyzed,which include the circular scan,sector scan,helical scan,raster scan,conical scan,electromechanical hybrid scan and two-dimensional electronic scan.Then,the time series of the pulse amplitude in the radar reconnaissance receiver is converted into an LPVG network,and the feature parameters are extracted.Finally,the recognition result is obtained by using a support vector machine(SVM)classifier.The experimental results show that the recognition accuracy and noise resistance of this new method are improved,where the average recognition accuracy for radar antenna type is at least 90%when the signalto-noise ratio(SNR)is 5 dB and above. 展开更多
关键词 antenna scan type limited penetrable visibility graph(LPVG) support vector machine(SVM) cognitive electronic warfare
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Targeting phosphodiesterases for cognition enhancement:a translational approach
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作者 Jos PRICKAERTS 《中国药理学与毒理学杂志》 CAS CSCD 北大核心 2017年第5期453-454,共2页
Cyclic adenosine monophosphate(cA MP) and/or cyclic guanosine monophosphate(cG MP)have been suggested to play specific roles in processes of memory. These cyclic nucleotides are hydrolyzed by specific enzymes,ie phosp... Cyclic adenosine monophosphate(cA MP) and/or cyclic guanosine monophosphate(cG MP)have been suggested to play specific roles in processes of memory. These cyclic nucleotides are hydrolyzed by specific enzymes,ie phosphodiesterases(PDEs). Thus,selective PDE inhibitors preventing the breakdown of cAMP and/or cGMP could improve memory. Studies with different timing of treatment with specific PDE inhibitors indicated that distinct underlying signaling pathways for early and late consolidation processes exist corresponding to specific time-windows for memory consolidation into longterm memory. There is evidence that the underlying mechanisms of PDE inhibition on the observed behavioral effects are independent of possible cerebrovascular effects. Most likely the underlying mechanisms are a cGMP/PKG pathway for early consolidation processes and a cAMP/PKA pathway for late consolidation processes. In addition,the early-phase cG MP/PKG signaling actually requires late-phase cAMP/PKA-signaling in long-term memory formation. Recently,the effects of specific PDE inhibitors are explored on other cognitive domains including acquisition processes/short-term memory and information processing. It will be shown that elevation of central cG MP levels or cA MP levels after treatment with a specific PDE inhibitor both improve acquisition processes/short-term memory. In vitro studying the effects of PDE inhibitors on long-term potentiation,the physiological substrate of memory,supportthe in vivo data and further show that AMPA receptor trafficking very likely mediates the memory enhancing effects. In a translational approach we initially also investigated the effects of cG MP elevation via PDE5 inhibition with vardenafil or sildenafil on cognition in humans. However,in contrast to studies with rodents and monkeys,PDE5 inhibition had no effect in humans on cognition including memory processes. It is clear that the transition of a drug from preclinical to clinical creates translational hurdles. Nevertheless,based on the expression patterns of its isoforms in the brain,PDE4,which is cAMP specific,appears more interesting for CNS targeting than PDE5. Indeed we found that a low dose of the PDE inhibitor roflumilast clearly improved cognition in humans. Interestingly,this pro-cognitive effect was not associated with emetic side effects(nausea,vomiting),which are commonly associated with PDE4 inhibition. Based on our data we suggest that the future for disease-specific PDE4 enzyme inhibition lies in the development of PDE4 isoform-specific inhibitors without emetic effects. Within the context as described above,the latest results of specific PDE inhibitors on cognitive processes will be presented and its implications will be discussed for finding and testing new cognition enhancers. 展开更多
关键词 PHOSPHODIESTERASES cognition MEMORY
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Research progresses of resting-state functional MRI in mild cognitive impairment and Alzheimer's disease 被引量:3
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作者 DUAN Huanqin LI Linqin QIU Lihua 《中国医学影像技术》 CSCD 北大核心 2024年第8期1254-1257,共4页
Alzheimer's disease(AD)is a prevalent neurodegenerative disease characterized by cognitive decline in the early stage.Mild cognitive impairment(MCI)is considered as an intermediate stage between normal aging and A... Alzheimer's disease(AD)is a prevalent neurodegenerative disease characterized by cognitive decline in the early stage.Mild cognitive impairment(MCI)is considered as an intermediate stage between normal aging and AD.In recent years,studies related to resting-state functional MRI(rs-fMRI)indicated that the occurrence and development process of MCI and AD might be closely linked to spontaneous brain activity and alterations in functional connectivity among brain regions,and rs-fMRI could provide important reference for specific diagnosis and early treatment of MCI and AD.The research progresses of rs-fMRI for MCI and AD were reviewed in this article. 展开更多
关键词 Alzheimer disease cognition disorders magnetic resonance imaging
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Role of PDE4D splice variants in the mediation of antidepressant and cognition-enhancing actions and its mechanisms
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作者 JIN Zeng-liang WANG Zhen-zhen +2 位作者 XU Yuan-yuan YANG Wei-xing LI Yun-feng 《中国药理学与毒理学杂志》 CAS CSCD 北大核心 2017年第5期457-458,共2页
OBJECTIVE Phosphodiesterase 4(PDE4),specific for cyclicAMP(cAMP)-hydrolyzing,has four isoforms(PDE4A-D) with at least 25 splice variants. PDE4 inhibitors produce definite antidepressant-like and cognitive-enhancing ef... OBJECTIVE Phosphodiesterase 4(PDE4),specific for cyclicAMP(cAMP)-hydrolyzing,has four isoforms(PDE4A-D) with at least 25 splice variants. PDE4 inhibitors produce definite antidepressant-like and cognitive-enhancing effects. However,none of PDE4 inhibitors has yet been approved for clinical utility so far due to the concomitant side effects. The present research is to explore the splice variants of PDE4 D responsible for antidepressant-like and cognitive-enhancing effects of PDE4 inhibitors but not side effects. METHODS Long-form PDE4 Ds were silenced by the bilateral microinfusion of lentiviral vector containing mi RNAs(4Dmi R) into the prefrontal cortex(PFC),PDE4D4 or D5 was overexpressed by the bilateral microinfusion of lentiviral vector containing full c DNA into hippocampus. Antidepressant-like behaviors were measured by tail-suspension test(TST),forced swimming test(FST)and chronic unpredictable stress model. Cognitive behaviors were measured by the novel object recognition test(NOR) and Morris water maze test(MWM) in both normal mice and the mice with chronic unpredictable stress-induced memory deficits. The emetic potential was evaluated by the assessment of the anaesthetic reversal effect,a surrogate of the emesis test in non-vomiting species. The expressions of PDE4 isoforms/splice variants and cAMP level were examined by Western-blot and ELISA analysis. The dendritic complexity and spine density were assessed by Golgi staining. RESULTS(1)High and specific expression of EGFP(green,indicator of 4Dmi R expression) in PFC was observed under fluorescence microscopy.(2) 4Dmi R significantly down-regulated PDE4D4/5 splice variants,but not PDE4 A,PDE4 B or PDE4D1/2/3.(3) 4Dmi R treatments significantly increased cAMP signaling and dendritic complexity in PFC.(4) Rolipram and/or 4Dmi R treatments significantly decreased immobility in TST and FST.(5) Rolipram and/or 4Dmi R treatments reversed the depressive-like behaviors in chronically stressed mice,including the reduced sucrose preference,prolonged latency to novelty-suppressed feeding and increased immobility in FST.(6) Rolipram and/or 4Dmi R treatments significantly increased the recognition index in NOR task and both the entries and durations in MWM task.(7) Rolipram and/or 4Dmi R treatments reversed the memory deficits in chronically stressed mice,including the reduced the recognition index in NOR task and the decreased durations in MWM task.(8) Rolipram and/or 4DmiR treatments reversed the decreased cA MP signaling,dendritic complexity and spine density.(9) Rolipram or plus 4Dmi R treatment significantly decreased the duration of anaesthesia in the alpha2 adrenergic receptor-mediated anesthesia,but not 4Dmi R treatment alone.(10)Hippocampal overexpression of PDE4D5,but not PDE4D4,produced depressive-like and cognitive defect behaviors,which were reversed by rolipram.The measurements including cAMP signaling,dendritic complexity and in vivo hippocampal LTP,showed the same changes. CONCLUSION Long-form PDE4 Ds,especially the PDE4D5,are the major isoforms responsible for antidepressant-like and cognitive-enhancing effects with little side effects. The critical roles of long-form PDE4 Ds are mediated by their regulation of cAMP signaling pathway and neuroplasticity. 展开更多
关键词 phosphodiesterase 4D RNA interference overexpressions ANTIDEPRESSANT cognitive prefrontal cortex HIPPOCAMPUS
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Natural Scene Classification Inspired by Visual Perception and Cognition Mechanisms
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作者 ZHANG Rui 《重庆理工大学学报(自然科学)》 CAS 2011年第7期24-43,共20页
The process of human natural scene categorization consists of two correlated stages: visual perception and visual cognition of natural scenes.Inspired by this fact,we propose a biologically plausible approach for natu... The process of human natural scene categorization consists of two correlated stages: visual perception and visual cognition of natural scenes.Inspired by this fact,we propose a biologically plausible approach for natural scene image classification.This approach consists of one visual perception model and two visual cognition models.The visual perception model,composed of two steps,is used to extract discriminative features from natural scene images.In the first step,we mimic the oriented and bandpass properties of human primary visual cortex by a special complex wavelets transform,which can decompose a natural scene image into a series of 2D spatial structure signals.In the second step,a hybrid statistical feature extraction method is used to generate gist features from those 2D spatial structure signals.Then we design a cognitive feedback model to realize adaptive optimization for the visual perception model.At last,we build a multiple semantics based cognition model to imitate human cognitive mode in rapid natural scene categorization.Experiments on natural scene datasets show that the proposed method achieves high efficiency and accuracy for natural scene classification. 展开更多
关键词 natural scene classification visual perception model visual cognition model
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Cognitive interference decision method for air defense missile fuze based on reinforcement learning 被引量:1
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作者 Dingkun Huang Xiaopeng Yan +2 位作者 Jian Dai Xinwei Wang Yangtian Liu 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期393-404,共12页
To solve the problem of the low interference success rate of air defense missile radio fuzes due to the unified interference form of the traditional fuze interference system,an interference decision method based Q-lea... To solve the problem of the low interference success rate of air defense missile radio fuzes due to the unified interference form of the traditional fuze interference system,an interference decision method based Q-learning algorithm is proposed.First,dividing the distance between the missile and the target into multiple states to increase the quantity of state spaces.Second,a multidimensional motion space is utilized,and the search range of which changes with the distance of the projectile,to select parameters and minimize the amount of ineffective interference parameters.The interference effect is determined by detecting whether the fuze signal disappears.Finally,a weighted reward function is used to determine the reward value based on the range state,output power,and parameter quantity information of the interference form.The effectiveness of the proposed method in selecting the range of motion space parameters and designing the discrimination degree of the reward function has been verified through offline experiments involving full-range missile rendezvous.The optimal interference form for each distance state has been obtained.Compared with the single-interference decision method,the proposed decision method can effectively improve the success rate of interference. 展开更多
关键词 cognitive radio Interference decision Radio fuze Reinforcement learning Interference strategy optimization
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Effect and mechanism of LW-AFC on chronic unpredictable mild stress-induced mood and cognition impairment of mice 被引量:1
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作者 Ming-hao ZHU Wen-xia ZHOU Ning JIANG 《中国药理学与毒理学杂志》 CAS CSCD 北大核心 2018年第4期344-345,共2页
OBJECTIVE To explore the effect and mechanisms of LW-AFC,a new formula derived fromLiuwei Dihuang decoction,on chronic unpredictable mild stress(CUMS)-induced mood and cogni.tion impairment in mice.METHODS C57 BL/6 J ... OBJECTIVE To explore the effect and mechanisms of LW-AFC,a new formula derived fromLiuwei Dihuang decoction,on chronic unpredictable mild stress(CUMS)-induced mood and cogni.tion impairment in mice.METHODS C57 BL/6 J mice were randomly placed into seven groups(n=10):normal control group,CUMS group,Fluoxetine(10 mg·kg^(-1),once per day) group,Liuwei Dihuang decoction group(LW,10 g·kg^(-1),once per day),and LW-AFC(0.8 g·kg^(-1),1.6 g·kg^(-1),3.2 g·kg^(-1),once per day) group.The stressed group was given CUMS for 4 weeks to set up a chronic multiple-stressed model.LW and LW-AFC was oral administered a week prior to CUMS and until the end of the study(a total of 35 d),while fluoxetine was administrated orally for 4 weeks.The anxiety behavior was analyzed using the open field test(OFT) and elevated plus maze test(EPM).The depression behavior was ana.lyzed using the sucrose preference test(SPT) and forced swimming test(FST).Spatial cognition was evaluated using Morris water maze(MWM) test and working memory was evaluated using new object recognition test(NORT).RESULTS CUMS for 28 d increased depressive-and anxiety-like behaviors.LW-AFC(1.6 g·kg^(-1)) significantly increased the numbers of entries into the open arm and time in the open arm of CUMS mice(P<0.05).LW-AFC(3.2 g·kg^(-1)) increased sucrose consumption and de.creased the immobility time of FST(P<0.01) of CUMS mice.The MWM test showed that spatial learning andmemory in CUMS mice were remarkably affected relative to controls,whereas LW-AFC(3.2 g·kg^(-1)) im.proves cognitive functions(P<0.05).CONCLUSION The mood and theability of learning and memory of thestressed group can be affected after exposure to CUS.Oral administration of LW-AFC significant.ly improved CUMS-induced impairments of mood and cognition in mice. 展开更多
关键词 六味地黄汤 中医 治疗方法 临床分析
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Maresin 1 alleviates neuroinflammation and cognitive decline in a mouse model of cecal ligation and puncture
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作者 LI Longyan XING Manyu +1 位作者 WANG Lu ZHAO Yixia 《中南大学学报(医学版)》 CAS CSCD 北大核心 2024年第6期890-902,共13页
Objective:Inflammation in the central nervous system plays a crucial role in the occurrence and development of sepsis-associated encephalopathy.This study aims to explore the effects of maresin 1(MaR1),an anti-inflamm... Objective:Inflammation in the central nervous system plays a crucial role in the occurrence and development of sepsis-associated encephalopathy.This study aims to explore the effects of maresin 1(MaR1),an anti-inflammatory and pro-resolving lipid mediator,on sepsis-induced neuroinflammation and cognitive impairment.Methods:Mice were randomly assigned to 4 groups:A sham group(sham operation+vehicle),a cecal ligation and puncture(CLP)group(CLP operation+vehicle),a MaR1-LD group(CLP operation+1 ng MaR1),and a MaR1-HD group(CLP operation+10 ng MaR1).MaR1 or vehicle was intraperitoneally administered starting 1 h before CLP operation,then every other day for 7 days.Survival rates were monitored,and serum inflammatory cytokines[tumor necrosis factor alpha(TNF-α),interleukin(IL)-1β,and IL-6]were measured 24 h after operation using enzyme-linked immunosorbent assay(ELISA).Cognitive function was assessed 7 days after operation using the Morris water maze(MWM)test and novel object recognition(NOR)task.The mRNA expression of TNF-α,IL-1β,IL-6,inducible nitric oxide synthase(iNOS),IL-4,IL-10,and arginase 1(Arg1)in cortical and hippocampal tissues was determined by real-time reverse transcription PCR(RT-PCR).Western blotting was used to determine the protein expression of iNOS,Arg1,signal transducer and activator of transcription 6(STAT6),peroxisome proliferator-activated receptor gamma(PPARγ),and phosphorylated STAT6(p-STAT6)in hippocampal tissue.Microglia activation was visualized via immunofluorescence.Mice were also treated with the PPARγantagonist GW9662 to confirm the involvement of this pathway in MaR1’s effects.Results:CLP increased serum levels of TNF-α,IL-1β,and IL-6,and reduced body weight and survival rates(all P<0.05).Both 1 ng and 10 ng doses of MaR1 significantly reduced serum TNF-α,IL-1β,and IL-6 levels,improved body weight,and increased survival rates(all P<0.05).No significant difference in efficacy was observed between the 2 doses(all P>0.05).MWM test and NOR task indicated that CLP impaired spatial learning,which MaR1 mitigated.However,GW9662 partially reversed MaR1’s protective effects.Real-time RTPCR results demonstrated that,compared to the sham group,mRNA expression of TNF-α,IL-1β,and iNOS significantly increased in hippocampal tissues following CLP(all P<0.05),while IL-4,IL-10,and Arg1 showed a slight decrease,though the differences were not statistically significant(all P>0.05).Compared to the CLP group,both 1 ng and 10 ng MaR1 decreased TNF-α,IL-1β,and iNOS mRNA expression in hippocampal tissues and increased IL-4,IL-10,and Arg1 mRNA expression(all P<0.05).Immunofluorescence results indicated a significant increase in Iba1-positive microglia in the hippocampus after CLP compared to the sham group(P<0.05).Administration of 1 ng and 10 ng MaR1 reduced the percentage area of Iba1-positive cells in the hippocampus compared to the CLP group(both P<0.05).Western blotting results showed that,compared to the CLP group,both 1 ng and 10 ng MaR1 down-regulated the iNOS expression,while up-regulated the expression of Arg1,PPARγ,and p-STAT6(all P<0.05).However,the inclusion of GW9662 counteracted the MaR1-induced upregulation of Arg1 and PPARγcompared to the MaR1-LD group(all P<0.05).Conclusion:MaR1 inhibits the classical activation of hippocampal microglia,promotes alternative activation,reduces sepsis-induced neuroinflammation,and improves cognitive decline. 展开更多
关键词 SEPSIS cognitive decline maresin 1 MICROGLIA NEUROINFLAMMATION
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Hippocampal HMGB1/TLR4 Pathway Mediates Cognitive Dysfunction in Chronic Stress Mice
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作者 HU Wen KUANG Xin +4 位作者 FENG Xin-Xiang ZHONG Wen-Long JIN Xin JIANG Jia-Mei ZOU Wei 《生物化学与生物物理进展》 SCIE CAS CSCD 北大核心 2024年第12期3266-3278,共13页
Objective Chronic stress can induce cognitive dysfunction,but the underlying mechanisms remain unknown.Studies have confirmed that the high mobility group box 1/Toll-like receptor 4(HMGB1/TLR4)pathway is closely assoc... Objective Chronic stress can induce cognitive dysfunction,but the underlying mechanisms remain unknown.Studies have confirmed that the high mobility group box 1/Toll-like receptor 4(HMGB1/TLR4)pathway is closely associated with cognitive impairment.Therefore,this research aimed to explore whether the HMGB1/TLR4 pathway involves in chronic stress-induced cognitive dysfunction.Methods The chronic unpredictable mild stress(CUMS)mouse model was established by randomly giving different types of stress every day for four consecutive weeks.Cognitive function was detected by novel object recognition test,Y-maze test,and Morris water maze test.The protein expressions of HMGB1,TLR4,B-cell lymphoma 2(BCL2),and BCL2 associated X(BAX)were determined by Western blot.The damage of neurons in the hippocampal CA1 region was observed by hematoxylin-eosin(HE)staining.Results The protein expressions of HMGB1 and TLR4 were significantly increased in the hippocampus of chronic stress mice.Furthermore,inhibition of the HMGB1/TLR4 pathway induced by ethyl pyruvate(EP,a specific inhibitor of HMGB1)and TAK242(a selective inhibitor of TLR4)treatment attenuated cognitive impairment in chronic stress mice,according to the novel object recognition test,Y-maze test,and Morris water maze test.In addition,administration of EP and TAK242 also mitigated the increase of apoptosis in the hippocampus of chronic stress mice.Conclusion These results indicate that the hippocampal HMGB1/TLR4 pathway contributes to chronic stress-induced apoptosis and cognitive dysfunction. 展开更多
关键词 chronic stress cognitive dysfunction HMGB1/TLR4 pathway APOPTOSIS HIPPOCAMPUS
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Holistic Cognition and Meanings of Restricted Combinations
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作者 Wang Ping 《学术界》 CSSCI 北大核心 2012年第10期267-272,共6页
A restricted combination is a kind of language phenomena.It is important in language.It is relatively-stationary phrase.Though it is conposed of more than one word,its meaning isn't only literal meaning expressed ... A restricted combination is a kind of language phenomena.It is important in language.It is relatively-stationary phrase.Though it is conposed of more than one word,its meaning isn't only literal meaning expressed by the words,but holistic.The whole isn't equal to the part.In the process of understanding restricted combinations,holistic congnition can play an important role. 展开更多
关键词 英文摘要 优秀文摘 中国 历史文化
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西藏自治区认知障碍疾病知晓度调查及影响因素分析 被引量:1
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作者 郝渝 王俊山 +7 位作者 卓玛 索朗曲珍 季士勇 胡亚雄 丁志杰 次旦卓嘎 袁晶 赵玉华 《协和医学杂志》 北大核心 2025年第2期472-478,共7页
目的调查西藏自治区居民对认知障碍疾病的知晓度及其影响因素,从而为针对性开展防治工作提供依据。方法2024年4—12月对西藏自治区年龄≥18岁的常住居民(在西藏自治区居住180 d及以上)开展问卷调查(线上问卷调查为主,辅以医务人员在社... 目的调查西藏自治区居民对认知障碍疾病的知晓度及其影响因素,从而为针对性开展防治工作提供依据。方法2024年4—12月对西藏自治区年龄≥18岁的常住居民(在西藏自治区居住180 d及以上)开展问卷调查(线上问卷调查为主,辅以医务人员在社区义诊时发放问卷二维码)。收集被调查者人口学信息及关于认知障碍疾病知晓度的相关资料,并采用有序Logistic回归模型分析总体人群/按职业分层后认知障碍疾病知晓度的影响因素。结果共收集问卷327份,剔除14份(被调查者未达西藏自治区居住时间13份,自我报告曾被诊断为认知障碍1份),最终纳入313份有效问卷。被调查者平均年龄(42.0±11.9)岁;男性108人(34.5%),女性205人(65.5%);主要来自拉萨市(78.6%,246/313);医务工作者179人(57.2%),非医务工作者134人(42.8%)。在认知障碍疾病知晓度方面,“不知晓”“部分知晓”“知晓良好”者分别占比7.3%(23/313)、75.7%(237/313)、16.9%(53/313)。有序Logistic回归模型显示,受教育程度为高中及以下(OR=2.82,95%CI:1.18~6.75,P=0.020)、非医务工作者(OR=4.03,95%CI:2.00~8.14,P<0.001)、未接触过认知障碍患者(OR=2.95,95%CI:1.64~5.32,P<0.001)与较低的疾病知晓度相关。按职业分层进行亚组分析显示,受教育程度为高中及以下(OR=3.00,95%CI:1.10~8.15,P=0.031)、未接触过认知障碍患者(OR=3.13,95%CI:1.14~8.60,P=0.027)与非医务工作者较低的疾病知晓度相关;未接触过认知障碍患者(OR=3.40,95%CI:1.61~7.20,P=0.001)与医务工作者较低的疾病知晓度相关。结论西藏自治区居民对认知障碍疾病的知晓度有待提升,文化水平、职业、既往是否接触过认知障碍患者可影响居民的疾病知晓度。提升整体教育水平,通过展示生动案例的临床表现有助于提高公众对认知障碍疾病的知晓度,是健康教育及科普宣传的重点。 展开更多
关键词 认知障碍 阿尔茨海默病 知晓度 西藏
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基于C-A-C的生成式AI用户间歇性中辍行为研究 被引量:2
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作者 周涛 张春雷 邓胜利 《现代情报》 北大核心 2025年第3期40-50,64,共12页
[目的/意义]用户的间歇性中辍作为一种消极行为,将影响生成式AI的用户保持及获取持续竞争优势。因此,有必要研究用户间歇性中辍的形成机理,发现显著的影响因素。[方法/过程]基于认知—情感—意愿(Cognition-Affect-Conation,C-A-C),从... [目的/意义]用户的间歇性中辍作为一种消极行为,将影响生成式AI的用户保持及获取持续竞争优势。因此,有必要研究用户间歇性中辍的形成机理,发现显著的影响因素。[方法/过程]基于认知—情感—意愿(Cognition-Affect-Conation,C-A-C),从“使能”与“抑制”双重视角研究了生成式AI用户间歇性中辍行为。使能因素包括隐私担忧、信息幻觉、认知失调;抑制因素包括智能化、拟人化、个性化、情感承诺。采用结构方程模型(Structural Equation Modeling,SEM)和模糊集定性比较分析(fuzzy-set Qualitative Comparative Analysis,fsQCA)进行数据分析。[结果/结论]隐私担忧和信息幻觉影响认知失调,进而导致间歇性中辍行为。智能化、拟人化、个性化影响情感承诺,进而对间歇性中辍产生抑制作用。研究结果显示,生成式AI一方面需要缓解用户的隐私担忧,减少信息幻觉,从而降低用户认知失调;另一方面,需要通过提高系统的智能化、拟人化、个性化等功能水平,增进用户情感承诺,从而抑制其间歇性中辍行为。 展开更多
关键词 生成式AI 间歇性中辍 C-A-C 认知失调 情感承诺
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基于认知负荷理论的计算机组成原理实验教学设计与应用 被引量:1
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作者 杨磊 司国东 +3 位作者 王春桃 黄沛杰 肖克辉 杜治国 《实验室研究与探索》 北大核心 2025年第1期177-181,共5页
计算机组成原理实验教学能提高学生系统设计及应用创新能力,但因其实验原理抽象、知识点多,实验平台复杂等特点也让学生在实验过程中产生较高的认知负荷。为解决高认知负荷对实验教学造成的负面影响,基于认知负荷理论对实验进行教学设计... 计算机组成原理实验教学能提高学生系统设计及应用创新能力,但因其实验原理抽象、知识点多,实验平台复杂等特点也让学生在实验过程中产生较高的认知负荷。为解决高认知负荷对实验教学造成的负面影响,基于认知负荷理论对实验进行教学设计,分析学生学习需要因材施教控制学生内部认知负荷,优化实验教材设计及呈现方式降低学生外部认知负荷,激发学生学习兴趣以提高学生相关认知负荷,提升实验教学效果。教学实践表明,新型教学设计有效降低学生实验过程中的认知负荷总量,计算机系统设计及创新能力得到较高的提升。此方法也可为其他实验课程教学改革提供参考。 展开更多
关键词 计算机组成原理 认知负荷理论 实验教学 成效研究
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动作如何影响元认知?——基于认知模型和神经机制的探讨 被引量:1
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作者 程晓荣 仇式明 +1 位作者 定险峰 范炤 《心理科学进展》 北大核心 2025年第3期425-438,共14页
动作与元认知是认知加工的重要环节。元认知体现个体对认知过程的表征、监控与调控;动作则是输出内部认知加工,尤其是决策信息的重要手段。研究表明,动作的各个方面(如反应速度、反应强度、反应顺序、反应冲突及反应观察等)均影响元认... 动作与元认知是认知加工的重要环节。元认知体现个体对认知过程的表征、监控与调控;动作则是输出内部认知加工,尤其是决策信息的重要手段。研究表明,动作的各个方面(如反应速度、反应强度、反应顺序、反应冲突及反应观察等)均影响元认知。从认知模型角度,元认知的决策后模型较好地适用于解释动作影响元认知的相关实验证据。该类模型认为用于元认知评估的信息(元认知证据)与用于知觉判断的信息(知觉证据)不同但相关,并分别侧重于层级加工、贝叶斯计算、信心增效等方面。从神经机制角度,动作与知觉信息可能通过以额叶皮层为核心的脑网络整合,依托β振荡和α抑制等电生理机制,在注意调控下形成元认知。未来研究可以进一步探讨动作改变元认知的边界条件、信心反映的真实含义,以及特殊人群的元认知表现等。 展开更多
关键词 动作 元认知 知觉判断 信心评估 认知神经机制
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大语言模型应用中的司法偏误与认知干预 被引量:1
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作者 李学尧 《政治与法律》 北大核心 2025年第5期65-76,共12页
近期的实验研究和司法实践都表明,单纯依赖简单的人机协作,难以有效遏制法官在自我确认偏误与大语言模型“强化输出”之间的共振效应。为避免大语言模型在司法实践中沦为单向度的技术支配,在挖掘传统法学方法论中关于多元价值论证的基础... 近期的实验研究和司法实践都表明,单纯依赖简单的人机协作,难以有效遏制法官在自我确认偏误与大语言模型“强化输出”之间的共振效应。为避免大语言模型在司法实践中沦为单向度的技术支配,在挖掘传统法学方法论中关于多元价值论证的基础上,可结合认知科学的防偏误机制,提出“认知协同司法决策模型(六步法)”。该模型通过在确立争点、规范检索、事实认定、裁判形成、价值审查与最终公开说理的全流程中引入对立论证、逆向思维、强制反驳清单等操作环节,帮助法官保持深度审查与反思能力,抵消大语言模型单一输出的强化效应。案例模拟表明,这一模型在提升信息搜索效率的同时,能够强化裁判对社会多元价值的考量,确保法官主体地位与裁判公正性。 展开更多
关键词 大语言模型 机器权威 法学方法论 认知科学 认知协同决策
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基于空时分形的网络流量认知模型
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作者 汤萍萍 张晖 +1 位作者 董育宁 董国青 《通信学报》 北大核心 2025年第5期258-271,共14页
为解决传统分形特征在网络流量认知精度和速度上难以兼具的问题,以分形理论为基础提出网络流量空时分离思想并创建空时分形特征,以此设计一种新型的流量认知模型——空时分形模型(SFM)。空时分形观测空间序列和时间序列,然后基于勒让德... 为解决传统分形特征在网络流量认知精度和速度上难以兼具的问题,以分形理论为基础提出网络流量空时分离思想并创建空时分形特征,以此设计一种新型的流量认知模型——空时分形模型(SFM)。空时分形观测空间序列和时间序列,然后基于勒让德变换建立向量再折射到对偶空间形成特征。空时分形的物理含义在于从不同空间和时间尺度上获得数据突发特征,而传统分形是空时分形在空间和时间维度上的特征融合,空时分形相比传统分形刻画出更多细节特征,以此进行流量认知更为精准。此外,空时分形相比传统分形更易计算,使SFM在增强认知精度的同时提升认知速度。实验数据显示,SFM的认知性能优于其他方法。 展开更多
关键词 网络流量 认知精度 认知速度 分形理论
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血液科医生对高级执业护师角色的认知与期望:一项质性研究 被引量:1
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作者 刘玲玉 闫婷婷 +4 位作者 李晓宾 郭锦丽 郭建利 魏巍 李明子 《护理研究》 北大核心 2025年第8期1352-1356,共5页
目的:探讨血液科医生对高级执业护师角色的认知与期望,为血液科高级执业护师岗位设置和执业内容设计提供参考。方法:采用目的抽样法,基于最大差异原则,于2023年1月—2月选取山西省4所三级甲等医院的13名血液科医生进行半结构式深度访谈... 目的:探讨血液科医生对高级执业护师角色的认知与期望,为血液科高级执业护师岗位设置和执业内容设计提供参考。方法:采用目的抽样法,基于最大差异原则,于2023年1月—2月选取山西省4所三级甲等医院的13名血液科医生进行半结构式深度访谈,运用Colaizzi 7步分析法进行意义构建、主题聚类、反馈核实。结果:共提炼出5个主题:复杂临床护理问题的解决者、护士执业范畴内的自主决策者、促进医护患密切合作的协调者、深耕血液护理专业的教育者、引领血液护理专业发展的研究者。结论:血液科医生认为临床实践需要高级执业护师角色,对高级执业护师的角色有较为明确的期望。 展开更多
关键词 血液科 高级执业护师 高级实践护士 角色 认知 期望 质性研究
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