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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:14
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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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Preference and Willingness of Consumers to Pay for Value-added Poultry Products in Niger Delta Region of Nigeria
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作者 Ofuoku A U Akusu M O 《Journal of Northeast Agricultural University(English Edition)》 CAS 2016年第4期82-92,共11页
There has been a steady growth in demand for convenience and ready-cooked food has influenced the interest of poultry processors in developing value-added chicken products that meet consumers' demand/choice. A conjoi... There has been a steady growth in demand for convenience and ready-cooked food has influenced the interest of poultry processors in developing value-added chicken products that meet consumers' demand/choice. A conjoint analysis was done in this study on the survey of 975 chicken consumers in the Niger Delta Region of Nigeria, between March and September, 2014 to valuate consumers, preferences and willingness to pay (WTP) for various chicken attributed parts, production method, processing method, storage method, the presence of flavor and cooking method. The estimates of consumers, WTP premium prices for various mixtures of value-added characteristics were ascertained. The consumers preferred chicken products refrigerated, from chicken produced under free-range management, chicken breast, chicken product that was addictive and flavor free, which could be oven-heated or pan heated. One half of the entire respondents were willing to pay about 25% more for value-added chicken product over the price for conventional products. On the whole, a premium for value-added chicken products was more likely to be paid for by young consumers, consumers who patronized farmers' markets and preferred free-range or organic chicken products. WTP by consumers was negatively affected by price of products. The poultry industry could utilize combined knowledge of consumers' WTP for value-added chicken product price as a guide of develop innovative value-added chicken products. 展开更多
关键词 consumer preference willingness to pay chicken attributes conjoint analysis
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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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Drinking pattern and its relation to hemoglobin concentration in local brew consumers from the Kathmandu Region 被引量:1
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作者 Arun Kumar 《海南医学院学报》 CAS 2009年第2期119-121,共3页
The study was conducted to determine the hemoglobin concentration in alcohol consumers(home made brew-Chang) and compare it with non-alcoholics healthy subjects.Hemoglobin(Hb) concentration was determined in 2053 alco... The study was conducted to determine the hemoglobin concentration in alcohol consumers(home made brew-Chang) and compare it with non-alcoholics healthy subjects.Hemoglobin(Hb) concentration was determined in 2053 alcoholic consumers(males: 1056;females: 997) and was compared with 1 027(males: 623;females: 404) healthy non-alcoholic control subjects.The Hb concentration in alcoholic male and female were 13.42 ± 2.14 g/dL and 12.19 ± 1.55 g/dL compared with control showing 14.43 ± 1.07 g/dL and 12.73 ± 1.41 g/dL in males and females respectively.The differences in Hb concentration between alcoholic and non-alcoholic consumers were highly significant in both genders with a P value of 0.000 674 in males and 0.004 732 in females.Alcohol Use Disorders Identification test(AUDIT) scores was advocated to alcoholic consumers to test the severity of drunkenness and disorders related to it.A total of 887 males and 663 females crossed the cut-off limits of ≥8 AUDIT scores showing the addiction towards drinking habits of local brew. 展开更多
关键词 血红蛋白浓度 酒精 酿酒工艺 生产技术
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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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On the Influence of Internet Word of Mouth (IWOM) on Consumers' Purchase Orientation
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作者 Wang Qing 《学术界》 CSSCI 北大核心 2013年第5期261-265,共5页
The development of the Internet is making IWOM focus of different marketing strategies because of its role in consumer's purchase orientation. Therefore,to guide consumers to rational consumption,some optimizing m... The development of the Internet is making IWOM focus of different marketing strategies because of its role in consumer's purchase orientation. Therefore,to guide consumers to rational consumption,some optimizing measures can be taken to improve its utilization efficiency on their purchase decision. This paper plans to explore,through modular modeling method,the main factors that could determine the influence of IWOM on consumers' purchase orientation. It is divided into three key parts. The first part studies the status of IWOM through a mathematical modeling. Part Two probes the solutions. The third part tries to verify with an empirical case the effect of the model in improving the advantage of the positive feedback relationship between the IWOM and its utilization efficiency. 展开更多
关键词 消费者 取向 反馈网络 市场策略 理性消费 建模方法 数学建模 验证模型
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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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知识图谱驱动智能学习的内生逻辑 被引量:7
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作者 吴杨 吕钰琪 +2 位作者 杜钧 牛红伟 郝佳 《中国电化教育》 北大核心 2025年第2期122-130,共9页
知识图谱愈加成为教育数字化基础设施的重要组成部分,相关应用逐渐增多,但知识图谱作用于教与学的应用逻辑与应用场景仍有待挖掘。基于当前的智能学习面临着碎片化严重、联通性不足、知识库缺失的问题,该研究以经典学习理论为基础,以学... 知识图谱愈加成为教育数字化基础设施的重要组成部分,相关应用逐渐增多,但知识图谱作用于教与学的应用逻辑与应用场景仍有待挖掘。基于当前的智能学习面临着碎片化严重、联通性不足、知识库缺失的问题,该研究以经典学习理论为基础,以学习者处理学习任务时的认知活动为状态,从认知心理的角度探究知识图谱驱动下的智能学习机制,为解决三个主要问题提出针对性的解决方案。第一,针对知识碎片化的问题,知识图谱通过将知识串联成网络,促进学习中的认知加工,减少碎片化学习;第二,针对知识点冗余的问题,知识图谱通过合并相同知识点、增加跨学科知识的联系,提高了学习中的智能联结,激发学习者主动探索,并主动形成知识构建活动;第三,针对知识库缺失的问题,知识图谱平台通过集成知识点、学习资源库与学生的学习行为,使学习的个性化推荐有据可依。基于学习者运用知识图谱学习的理论机制,未来知识图谱的教育教学创新方向将聚焦于个性化、自适应、探索性、反馈性的学习平台搭建,为推进教育教学的智能化变革提供理论支撑。 展开更多
关键词 知识图谱 智能学习 认知机制 学习理论
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算法价格歧视违法性认定的挑战与应对 被引量:6
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作者 曾迪 《中国流通经济》 北大核心 2025年第2期115-126,共12页
算法技术在数据收集、分析和应用等方面的优势能够帮助经营者快速实现价格歧视,提高经营效率。但算法价格歧视行为却对市场其他主体带来损害性影响,包括破坏社会对网络市场的公平感知、扭曲市场竞争秩序、侵害消费者知情权等传统权利和... 算法技术在数据收集、分析和应用等方面的优势能够帮助经营者快速实现价格歧视,提高经营效率。但算法价格歧视行为却对市场其他主体带来损害性影响,包括破坏社会对网络市场的公平感知、扭曲市场竞争秩序、侵害消费者知情权等传统权利和个人信息权等新型权益。为避免上述系列损害性后果持续扩散,亟须对司法实践如何开展算法价格歧视违法性认定做出回应。然而,基于我国当前相关法条分布零散且适用性不强、违法性认定规则的合理性和可行性存疑、抗辩理由适用不明等现实困境,司法实务部门在处理算法价格歧视案件时仍面临严峻挑战。原有的经营者滥用市场支配地位认定路径和违规处理个人信息认定路径不能满足现实司法实践所需,有必要从立法和司法层面对算法价格歧视违法性认定的第三条路径予以拓展与优化。在立法完善过程中,《电子商务法》作为我国电商领域的综合性法律,尤其适合作为规制算法价格歧视的法律依据,建议该法新增“不正当价格行为”违法认定类型,明确将保护消费者知情权和选择权不受侵犯设为底线,确立过错推定原则以平衡当事人之间的证明责任。在算法价格歧视违法性认定的司法实践中,坚持行为主体聚焦、侵害客体明晰、主观违背注意义务、客观造成消费者利益受损的“四要件”认定方法。在此基础上,《电子商务法》通过与《反垄断法》《个人信息保护法》等多部法律之间的协同配合,进一步夯实算法价格歧视违法性认定的法律基础,才能共同助力司法实践顺利推进。 展开更多
关键词 算法时代 算法价格歧视 消费者权益 违法性认定
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老年高血压患者血压水平与认知功能异常的相关性分析:一项全国多中心横断面研究 被引量:1
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作者 贾瑶 邝文娟 +4 位作者 殷鹏 周脉耕 季福绥 王志会 于雪 《中国心血管杂志》 北大核心 2025年第4期359-367,共9页
目的探讨老年高血压患者血压水平与认知功能异常的相关性。方法横断面研究。采用多阶段分层整群随机抽样方法,从全国6个地区选取26164名老年人,最终纳入23271名,平均年龄(70.5±10.9)岁,男性10352名,占比44.5%。通过问卷调查、体格... 目的探讨老年高血压患者血压水平与认知功能异常的相关性。方法横断面研究。采用多阶段分层整群随机抽样方法,从全国6个地区选取26164名老年人,最终纳入23271名,平均年龄(70.5±10.9)岁,男性10352名,占比44.5%。通过问卷调查、体格检查和血液生化指标检测采集数据。采用8项痴呆筛查问卷(AD8)、简易精神状态检查(MMSE)问卷和神经科医师问诊三阶段评估方式进行认知障碍筛查及痴呆诊断。比较高血压组和非高血压组一般情况及认知功能障碍和痴呆患病率差异。比较遵医嘱用药的高血压患者在不同血压水平下认知功能障碍和痴呆患病率差异。采用多因素logisitic回归分析不同血压水平与认知功能异常的相关性。比较高血压组与非高血压组MMSE各维度评分的差异。比较高血压组不同认知功能水平下血压控制率和用药依从性的差异。结果两组年龄、体质指数和三酰甘油水平及男性、文盲、吸烟、饮酒、运动不足、失眠、冠心病史、脑卒中史和糖尿病史等患者比例比较,差异均有统计学意义(均为P<0.05)。高血压组AD8评分≥2、MMSE评分异常及痴呆的比例均高于非高血压组(均为P<0.05)。血压范围为120~139/80~89 mmHg时认知功能障碍的患病率最低,血压范围在90~119/80~89 mmHg时痴呆的患病率最低。在60~69岁人群中,血压是痴呆的独立影响因素(OR=1.697,P<0.001)。多因素logisitic回归分析结果显示,收缩压<90 mmHg和160~179 mmHg均与AD8评分≥2和MMSE评分异常存在关联,收缩压≥180 mmHg与MMSE评分异常和痴呆存在关联,舒张压<60 mmHg与AD8评分≥2和MMSE评分异常存在关联,舒张压100~109 mmHg与MMSE评分异常及痴呆存在关联,舒张压≥110 mmHg与AD8评分≥2和MMSE评分异常存在关联(均为P<0.05)。在总体和60~69岁人群中,高血压组MMSE条目中部分维度评分及MMSE总分均低于非高血压组(均为P<0.05)。高血压组中血压控制欠佳者在MMSE条目中所有维度评分及总分均低于血压控制良好者(均为P<0.001)。与MMSE评分正常者和非痴呆患者相比,MMSE评分异常者和痴呆患者中的血压控制欠佳比例均升高(均为P<0.05);与AD8评分<2及MMSE评分正常者相比,AD8评分≥2和MMSE评分异常的遵医嘱用药患者比例均降低(均为P<0.05)。随着MMSE评分增加,高血压患者血压控制欠佳患者比例逐渐降低(P<0.001)。结论与非高血压人群相比,高血压患者的认知功能障碍相关危险因素更多,认知功能更差。血压水平与认知功能障碍和痴呆具有相关性。高血压合并认知功能异常者较认知功能正常的高血压患者治疗依从性更差且血压控制率更低。维持血压在120~139/80~89 mmHg范围内可能更有利于保护老年高血压患者的认知功能。 展开更多
关键词 血压 老年人 认知功能障碍 痴呆 相关性
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