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Neural Tucker Factorization
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作者 Peng Tang Xin Luo 《IEEE/CAA Journal of Automatica Sinica》 2025年第2期475-477,共3页
Dear Editor,This letter presents a novel latent factorization model for high dimensional and incomplete (HDI) tensor, namely the neural Tucker factorization (Neu Tuc F), which is a generic neural network-based latent-... Dear Editor,This letter presents a novel latent factorization model for high dimensional and incomplete (HDI) tensor, namely the neural Tucker factorization (Neu Tuc F), which is a generic neural network-based latent-factorization-of-tensors model under the Tucker decomposition framework. 展开更多
关键词 neu tuc f neural tucker factorization latent factorization model high dimensional tensor tucker decomposition framework neural network incomplete tensor latent factorization
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Changes in factor profiles deriving from photochemical losses of volatile organic compounds:Insight from daytime and nighttime positive matrix factorization ana
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作者 Baoshuang Liu Tao Yang +9 位作者 Sicong Kang Fuquan Wang Haixu Zhang Man Xu Wei Wang Jinrui Bai Shaojie Song Qili Dai Yinchang Feng Philip K.Hopke 《Journal of Environmental Sciences》 2025年第5期627-639,共13页
Substantial effects of photochemical reaction losses of volatile organic compounds(VOCs)on factor profiles can be investigated by comparing the differences between daytime and nighttime dispersion-normalized VOC data ... Substantial effects of photochemical reaction losses of volatile organic compounds(VOCs)on factor profiles can be investigated by comparing the differences between daytime and nighttime dispersion-normalized VOC data resolved profiles.Hourly speciated VOC data measured in Shijiazhuang,China from May to September 2021 were used to conduct study.The mean VOC concentration in the daytime and at nighttime were 32.8 and 36.0 ppbv,respectively.Alkanes and aromatics concentrations in the daytime(12.9 and 3.08 ppbv)were lower than nighttime(15.5 and 3.63 ppbv),whereas that of alkenes showed the opposite tendency.The concentration differences between daytime and nighttime for alkynes and halogenated hydrocarbonswere uniformly small.The reactivities of the dominant species in factor profiles for gasoline emissions,natural gas and diesel vehicles,and liquefied petroleum gas were relatively low and their profiles were less affected by photochemical losses.Photochemical losses produced a substantial impact on the profiles of solvent use,petrochemical industry emissions,combustion sources,and biogenic emissions where the dominant species in these factor profiles had high reactivities.Although the profile of biogenic emissions was substantially affected by photochemical loss of isoprene,the low emissions at nighttime also had an important impact on its profile.Chemical losses of highly active VOC species substantially reduced their concentrations in apportioned factor profiles.This study results were consistent with the analytical results obtained through initial concentration estimation,suggesting that the initial concentration estimation could be the most effective currently availablemethod for the source analyses of active VOCs although with uncertainty. 展开更多
关键词 Volatile organic compounds Dispersion normalization Photochemical loss Factor profile Positive matrix factorization
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Research on Library Data Governance for Data Factorization
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作者 Yan Jiang 《Journal of Electronic Research and Application》 2025年第6期159-166,共8页
Data factors are becoming the core driving force in the intelligent transformation of libraries.Based on a systematic review of the progress in data governance practices in libraries both domestically and internationa... Data factors are becoming the core driving force in the intelligent transformation of libraries.Based on a systematic review of the progress in data governance practices in libraries both domestically and internationally,this study delves into the mechanism by which data governance promotes data factorization and proposes implementation paths for data governance oriented toward data factorization.The aim is to facilitate the intelligent transformation and high-quality development of libraries. 展开更多
关键词 Data factorization LIBRARIES Data governance Mechanism of action Practical paths
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Source apportionment of PM_(2.5) using dispersion normalized positive matrix factorization(DN-PMF)in Beijing and Baoding,China
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作者 Ilhan Ryoo Taeyeon Kim +6 位作者 Jiwon Ryu Yeonseung Cheong Kwang-joo Moon Kwon-ho Jeon Philip K.Hopke Seung-Muk Yi Jieun Park 《Journal of Environmental Sciences》 2025年第9期395-408,共14页
Fine particulatematter(PM_(2.5))samples were collected in two neighboring cities,Beijing and Baoding,China.High-concentration events of PM_(2.5) in which the average mass concentration exceeded 75μg/m^(3) were freque... Fine particulatematter(PM_(2.5))samples were collected in two neighboring cities,Beijing and Baoding,China.High-concentration events of PM_(2.5) in which the average mass concentration exceeded 75μg/m^(3) were frequently observed during the heating season.Dispersion Normalized Positive Matrix Factorization was applied for the source apportionment of PM_(2.5) as minimize the dilution effects of meteorology and better reflect the source strengths in these two cities.Secondary nitrate had the highest contribution for Beijing(37.3%),and residential heating/biomass burning was the largest for Baoding(27.1%).Secondary nitrate,mobile,biomass burning,district heating,oil combustion,aged sea salt sources showed significant differences between the heating and non-heating seasons in Beijing for same period(2019.01.10–2019.08.22)(Mann-Whitney Rank Sum Test P<0.05).In case of Baoding,soil,residential heating/biomass burning,incinerator,coal combustion,oil combustion sources showed significant differences.The results of Pearson correlation analysis for the common sources between the two cities showed that long-range transported sources and some sources with seasonal patterns such as oil combustion and soil had high correlation coefficients.Conditional Bivariate Probability Function(CBPF)was used to identify the inflow directions for the sources,and joint-PSCF(Potential Source Contribution Function)was performed to determine the common potential source areas for sources affecting both cities.These models facilitated a more precise verification of city-specific influences on PM_(2.5) sources.The results of this study will aid in prioritizing air pollution mitigation strategies during the heating season and strengthening air quality management to reduce the impact of downwind neighboring cities. 展开更多
关键词 Source apportionment Dispersion normalized positive matrix factorization Adjacent cities Inter-city impact Source location Heating season Air quality management
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Nonlinear Control for Unstable Networked Plants in the Presence of Actuator and Sensor Limitations Using Robust Right Coprime Factorization
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作者 Yuanhong Xu Mingcong Deng 《IEEE/CAA Journal of Automatica Sinica》 2025年第3期516-527,共12页
In this paper,a nonlinear control approach for an unstable networked plant in the presence of actuator and sensor limitations using robust right coprime factorization is proposed.The actuator is limited by upper and l... In this paper,a nonlinear control approach for an unstable networked plant in the presence of actuator and sensor limitations using robust right coprime factorization is proposed.The actuator is limited by upper and lower constraints and the sensor in the feedback loop is subjected to network-induced unknown time-varying delay and noise.With this nonlinear control method,we first employ right coprime factorization based on isomorphism and operator theory to factorize the plant,so that bounded input bounded output(BIBO)stability can be guaranteed.Next,continuous-time generalized predictive control(CGPC)is utilized for the unstable operator of the right coprime factorized plant to guarantee inner stability and enables the closed-loop dynamics of the system with predictive characteristics.Meanwhile,a second-Do F(degrees of freedom)switched controller that satisfies a perturbed Bezout identity and a robustness condition is designed.By using the CGPC controller that possesses predictive behavior and the second-Do F switched stabilizer,the overall stability of the plant subjected to actuator limitations is guaranteed.To address sensor limitations that exist in networked plants in the form of delay and noise which often cause system performance degradation,we implement an identity operator definition in the feedback loop to compensate for these adverse effects.Further,a pre-operator is designed to ensure that the plant output tracks the reference input.Finally,the effectiveness of the proposed design scheme is demonstrated by simulations. 展开更多
关键词 Actuator and sensor limitations identity operator definition network-induced limitations robust right coprime factorization unstable plant
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Predicting CircRNA-Disease Associations via Non-Negative Matrix Factorization Fused with Multiple Similarity Networks
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作者 LU Pengli LI Shiying 《Journal of Shanghai Jiaotong university(Science)》 2025年第4期709-719,共11页
CircRNAs,widely found throughout the human bodies,play a crucial role in regulating various biological processes and are closely linked to complex human diseases.Investigating potential associations between circRNAs a... CircRNAs,widely found throughout the human bodies,play a crucial role in regulating various biological processes and are closely linked to complex human diseases.Investigating potential associations between circRNAs and diseases can enhance our understanding of diseases and provide new strategies and tools for early diagnosis,treatment,and disease prevention.However,existing models have limitations in accurately capturing similarities,handling the sparse and noise attributes of association networks,and fully leveraging bioinformatical aspects from multiple viewpoints.To address these issues,this study introduces a new non-negative matrix factorization-based framework called NMFMSN.First,we incorporate circRNA sequence data and disease semantic information to compute circRNA and disease similarity,respectively.Given the sparse known associations between circRNAs and diseases,we reconstruct the network to complete more associations by imputing missing links based on neighboring circRNA and disease interactions.Finally,we integrate these two similarity networks into a non-negative matrix factorization framework to identify potential circRNA-disease associations.Upon conducting 5-fold cross-validation and leave-one-out cross-validation,the AUC values for NMFMSN reach 0.9712 and 0.9768,respectively,outperforming the currently most advanced models.Case studies on lung cancer and hepatocellular carcinoma show that NMFMSN is a good way to predict new associations between circRNAs and diseases. 展开更多
关键词 circRNA-disease associations circRNA sequence data disease semantic information non-negative matrix factorization
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Latent-Factorization-of-Tensors-Incorporated Battery Cycle Life Prediction
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作者 Minzhi Chen Li Tao +1 位作者 Jungang Lou Xin Luo 《IEEE/CAA Journal of Automatica Sinica》 2025年第3期633-635,共3页
Dear Editor,This letter presents a latent-factorization-of-tensors(LFT)-incorporated battery cycle life prediction framework.Data-driven prognosis and health management(PHM)for battery pack(BP)can boost the safety and... Dear Editor,This letter presents a latent-factorization-of-tensors(LFT)-incorporated battery cycle life prediction framework.Data-driven prognosis and health management(PHM)for battery pack(BP)can boost the safety and sustainability of a battery management system(BMS),which relies heavily on the quality of the measured BP data like the voltage(V),current(I),and temperature(T). 展开更多
关键词 health management battery pack bp can latent factorization tensors battery cycle life prediction health management phm battery cycle battery pack battery management system bms which
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心内科住院患者并发院内感染的危险因素调查
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作者 陈恒 赵登峰 +1 位作者 李杰 苏珊珊 《中国病原生物学杂志》 北大核心 2026年第1期82-85,共4页
目的分析心内科住院患者并发院内感染的危险因素,探讨炎性因子水平在感染发生中的作用。方法选取2023年1月至2024年12月本院心内科住院的152例合并院内感染患者作为研究对象,并纳入90例未感染患者作为对照组。采集感染患者标本进行病原... 目的分析心内科住院患者并发院内感染的危险因素,探讨炎性因子水平在感染发生中的作用。方法选取2023年1月至2024年12月本院心内科住院的152例合并院内感染患者作为研究对象,并纳入90例未感染患者作为对照组。采集感染患者标本进行病原体分离鉴定,检测血清白细胞介素-6(IL-6)和肿瘤坏死因子-α(TNF-α)水平。通过单因素χ2检验和多因素Logistic回归分析感染危险因素。结果152例院内感染患者中,医院获得性肺炎(43.42%)和导管相关血流感染(28.95%)为主要感染类型,共检出病原菌163株,以革兰阴性菌为主(57.67%),其中肺炎克雷伯菌(28.83%)最常见。感染组IL-6和TNF-α水平分别为(113.55±10.29)pg/mL和(88.41±8.38)pg/mL,显著高于非感染组(P<0.05),合并糖尿病患者水平显著高于非糖尿病患者(P<0.05)。单因素分析显示,年龄≥65岁、合并糖尿病、慢性肾病、COPD、侵入性操作≥2项、抗菌药物使用≥10 d及PPI使用与感染相关(P<0.05);多因素Logistic回归表明,年龄≥65岁(OR=19.652)、合并糖尿病(OR=11.926)、COPD(OR=6.399)、侵入性操作≥2项(OR=14.035)、抗菌药物使用≥10 d(OR=13.956)为独立危险因素(P<0.05)。结论心内科住院患者院内感染以革兰阴性菌为主,高龄、糖尿病、COPD、侵入性操作及长期抗菌药物使用是重要危险因素,监测炎性因子水平或可辅助感染评估,临床需针对高危因素制定防控策略。 展开更多
关键词 心内科 院内感染 危险因素 病原谱 炎性因子
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Sparseness-controlled non-negative tensor factorization and its application in machinery fault diagnosis 被引量:1
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作者 彭森 许飞云 +1 位作者 贾民平 胡建中 《Journal of Southeast University(English Edition)》 EI CAS 2009年第3期346-350,共5页
Aiming at the problems of bispectral analysis when applied to machinery fault diagnosis, a machinery fault feature extraction method based on sparseness-controlled non-negative tensor factorization (SNTF) is propose... Aiming at the problems of bispectral analysis when applied to machinery fault diagnosis, a machinery fault feature extraction method based on sparseness-controlled non-negative tensor factorization (SNTF) is proposed. First, a non-negative tensor factorization(NTF) algorithm is improved by imposing sparseness constraints on it. Secondly, the bispectral images of mechanical signals are obtained and stacked to form a third-order tensor. Thirdly, the improved algorithm is used to extract features, which are represented by a series of basis images from this tensor. Finally, coefficients indicating these basis images' weights in constituting original bispectral images are calculated for fault classification. Experiments on fault diagnosis of gearboxes show that the extracted features can not only reveal some nonlinear characteristics of the system, but also have intuitive meanings with regard to fault characteristic frequencies. These features provide great convenience for the interpretation of the relationships between machinery faults and corresponding bispectra. 展开更多
关键词 non-negative tensor factorization SPARSENESS feature extraction bispectrum gearbox
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Local hierarchical non-negative tensor factorization and its application in machinery fault diagnosis 被引量:1
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作者 王飞 许飞云 王海军 《Journal of Southeast University(English Edition)》 EI CAS 2011年第4期394-399,共6页
Aiming at the slow convergence and low accuracy problems of the traditional non-negative tensor factorization, a local hierarchical non-negative tensor factorization method is proposed by applying the local objective ... Aiming at the slow convergence and low accuracy problems of the traditional non-negative tensor factorization, a local hierarchical non-negative tensor factorization method is proposed by applying the local objective function theory to non- negative tensor factorization and combining the three semi-non- negative matrix factorization(NMF) model. The effectiveness of the method is verified by the facial feature extraction experiment. Through the decomposition of a series of an air compressor's vibration signals composed in the form of a bispectrum by this new method, the basis images representing the fault features and corresponding weight matrices are obtained. Then the relationships between characteristics and faults are analyzed and the fault types are classified by importing the weight matrices into the BP neural network. Experimental results show that the accuracy of fault diagnosis is improved by this new method compared with other feature extraction methods. 展开更多
关键词 non-negative tensor factorization BISPECTRUM feature extraction air compressor BP neural network
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光暴露对心力衰竭模型大鼠神经递质释放的影响及其分子机制
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作者 阮琳 李佳 +5 位作者 施丽南 朱红 吴东宁 郑迪 李雨鹏 赵妍 《中国组织工程研究》 北大核心 2026年第18期4649-4662,共14页
背景:心力衰竭发生发展与神经内分泌系统的异常激活密切相关。研究表明光暴露能够降低大鼠大脑中的多巴胺水平,进一步增强下丘脑室旁核内多巴胺能神经元的活动,从而促进促肾上腺皮质激素释放因子的释放。现并无直接证据证实光暴露会诱... 背景:心力衰竭发生发展与神经内分泌系统的异常激活密切相关。研究表明光暴露能够降低大鼠大脑中的多巴胺水平,进一步增强下丘脑室旁核内多巴胺能神经元的活动,从而促进促肾上腺皮质激素释放因子的释放。现并无直接证据证实光暴露会诱发心力衰竭。目的:探究光暴露对心力衰竭模型大鼠神经递质释放的影响及其分子机制,并进行细胞学验证。方法:①动物实验:将行心力衰竭造模的SD大鼠分为模型组、光暴露模型组、光暴露治疗组,将假手术大鼠分为光暴露对照组和空白组,每组各6只。8周实验结束后,使用ELISA检测光暴露对心衰大鼠血清神经递质、激素水平的影响,苏木精-伊红染色观察心脏病理变化;Western Blot检测核因子E2相关因子2/血红素氧化酶1/磷酸酰胺腺嘌呤二核苷酸醌氧化还原酶1信号通路的调节作用。②细胞实验:将小鼠心肌细胞(HL-1细胞)分为空白组、5-羟色胺高剂量对照组(5-羟色胺500 mg/mL)、脂多糖低剂量组(脂多糖1μg/mL)、脂多糖+5-羟色胺高剂量组(5-羟色胺500 mg/mL+脂多糖1μg/mL)、ML385组(脂多糖1μg/mL+5-羟色胺500 mg/mL+核因子E2相关因子2抑制剂ML385为2.5μg/mL)、白藜芦醇组(脂多糖1μg/mL+5-羟色胺500 mg/mL+核因子E2相关因子2激动剂白藜芦醇30μg/mL),干预36 h,考察各干预条件对于细胞增殖的影响,利用Western Blot方法,验证5-羟色胺对HL-1细胞核因子E2相关因子2/血红素氧化酶1/磷酸酰胺腺嘌呤二核苷酸醌氧化还原酶1信号轴的影响。结果与结论:①光暴露能提升心力衰竭模型大鼠血清中的去甲肾上腺素和5-羟色胺水平,加剧心脏损伤;光暴露模型组及模型组心肌组织病理均呈现了明显的损伤,细胞出现了肿胀、核皱缩、空泡等现象;光暴露治疗组大鼠心肌细胞的损伤得到了明显的缓解;光暴露对照组的血管紧张素转换酶2蛋白表达低于空白组(P<0.05)而高于模型组(P<0.05),而Mas、c-fos及血红素氧化酶1表达与空白组相比虽有所下调,但差异无显著性意义(P>0.05)。在光暴露模型组中,血管紧张素转换酶2、Mas、核因子E2相关因子2及血红素氧化酶1蛋白表达均较空白组显著下调(P<0.05)。与光暴露模型组相比,光暴露治疗组中核因子E2相关因子2/血红素氧化酶1/磷酸酰胺腺嘌呤二核苷酸醌氧化还原酶1信号通路相关蛋白表达均明显上调(P<0.05)。②细胞实验显示5-羟色胺增加了脂多糖所致的心肌细胞损伤,且该损伤效应与核因子E2相关因子2/血红素氧化酶1/磷酸酰胺腺嘌呤二核苷酸醌氧化还原酶1信号通路的抑制相关。结论:过度的光暴露可能通过调节神经递质组成,介导核因子E2相关因子2/血红素氧化酶1/磷酸酰胺腺嘌呤二核苷酸醌氧化还原酶1信号通路,加速心力衰竭的进程。 展开更多
关键词 光暴露 心力衰竭 神经递质 5-羟色胺 心肌细胞损伤 核因子E2相关因子2
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K_(1,p)~k-FACTORIZATION OF COMPLETE BIPARTITE GRAPHS 被引量:3
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作者 Du BeiliangDept.ofMath.,SuzhouUniv.,Suzhou215006.E-mail:dubl@pub.sz.jsinfo.ne 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2001年第2期107-110,共4页
In this paper, it is shown that a sufficient condition for the existence of a K 1,p k factorization of K m,n , whenever p is a prime number and k is a positive integer, is (1) m≤p kn,(2... In this paper, it is shown that a sufficient condition for the existence of a K 1,p k factorization of K m,n , whenever p is a prime number and k is a positive integer, is (1) m≤p kn,(2) n≤p km,(3)p kn-m≡p km-n ≡0(mod( p 2k -1 )) and (4) (p kn-m)(p km-n) ≡0(mod( p k -1)p k×(p 2k -1)(m+n)) . 展开更多
关键词 Bipartite graph FACTOR factorization.
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Microglia overexpressing brain-derived neurotrophic factor promote vascular repair and functional recovery in mice after spinal cord injury 被引量:2
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作者 Fanzhuo Zeng Yuxin Li +6 位作者 Xiaoyu Li Xinyang Gu Yue Cao Shuai Cheng He Tian Rongcheng Mei Xifan Mei 《Neural Regeneration Research》 2026年第1期365-376,共12页
Spinal cord injury represents a severe form of central nervous system trauma for which effective treatments remain limited.Microglia is the resident immune cells of the central nervous system,play a critical role in s... Spinal cord injury represents a severe form of central nervous system trauma for which effective treatments remain limited.Microglia is the resident immune cells of the central nervous system,play a critical role in spinal cord injury.Previous studies have shown that microglia can promote neuronal survival by phagocytosing dead cells and debris and by releasing neuroprotective and anti-inflammatory factors.However,excessive activation of microglia can lead to persistent inflammation and contribute to the formation of glial scars,which hinder axonal regeneration.Despite this,the precise role and mechanisms of microglia during the acute phase of spinal cord injury remain controversial and poorly understood.To elucidate the role of microglia in spinal cord injury,we employed the colony-stimulating factor 1 receptor inhibitor PLX5622 to deplete microglia.We observed that sustained depletion of microglia resulted in an expansion of the lesion area,downregulation of brain-derived neurotrophic factor,and impaired functional recovery after spinal cord injury.Next,we generated a transgenic mouse line with conditional overexpression of brain-derived neurotrophic factor specifically in microglia.We found that brain-derived neurotrophic factor overexpression in microglia increased angiogenesis and blood flow following spinal cord injury and facilitated the recovery of hindlimb motor function.Additionally,brain-derived neurotrophic factor overexpression in microglia reduced inflammation and neuronal apoptosis during the acute phase of spinal cord injury.Furthermore,through using specific transgenic mouse lines,TMEM119,and the colony-stimulating factor 1 receptor inhibitor PLX73086,we demonstrated that the neuroprotective effects were predominantly due to brain-derived neurotrophic factor overexpression in microglia rather than macrophages.In conclusion,our findings suggest the critical role of microglia in the formation of protective glial scars.Depleting microglia is detrimental to recovery of spinal cord injury,whereas targeting brain-derived neurotrophic factor overexpression in microglia represents a promising and novel therapeutic strategy to enhance motor function recovery in patients with spinal cord injury. 展开更多
关键词 ANGIOGENESIS apoptosis brain-derived neurotrophic factor colony stimulating factor 1 receptor inflammation MICROGLIA motor function spinal cord injury vascular endothelial growth factor
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动脉粥样硬化患者口腔菌群特征及炎症因子水平的关联分析
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作者 林瑜 董桐俊 +2 位作者 辛立栋 王凤云 赵明 《中国病原生物学杂志》 北大核心 2026年第1期6-12,共7页
目的探讨动脉粥样硬化(AS)患者口腔菌群多样性与炎症因子水平的特征及关联。方法纳入AS患者50例与健康对照50例,采集唾液和血样进行16S rRNA测序、IL-6、IL-1β、TNF-α、CRP检测;比较两组菌群结构与炎症指标差异,并进行Spearman相关和... 目的探讨动脉粥样硬化(AS)患者口腔菌群多样性与炎症因子水平的特征及关联。方法纳入AS患者50例与健康对照50例,采集唾液和血样进行16S rRNA测序、IL-6、IL-1β、TNF-α、CRP检测;比较两组菌群结构与炎症指标差异,并进行Spearman相关和多因素回归分析。结果AS组IL-6、IL-1β、TNF-α、CRP水平均显著高于对照组(IL-6:8.24±2.15 vs 6.15±1.76,P<0.01;CRP:7.42±2.41 vs 3.98±1.57,P<0.01);口腔菌群Shannon指数低于对照组(4.38±0.55 vs 4.61±0.52,P=0.040);Fusobacterium与CRP、IL-6正相关(r=0.41、0.36,均P<0.05)。多因素回归提示Fusobacterium丰度及IL-6、CRP水平均为AS潜在危险因素。结论AS患者口腔菌群多样性下降伴随炎症显著增高,二者或通过免疫和代谢途径相互作用,为AS的风险评估与干预策略提供新的思路。 展开更多
关键词 动脉粥样硬化 口腔菌群 炎症因子 16S rRNA测序
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考虑协偏度的基金业绩评价研究
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作者 王鹏 陈琪 梁鑫垚 《证券市场导报》 北大核心 2026年第1期56-69,共14页
协偏度度量一项资产对市场尾部风险的贡献,是一种重要的系统性风险,亦是资产定价中的重要变量之一。在基金管理中,基金经理可通过投资负协偏度资产来承担协偏度风险,进而获取协偏度风险溢价。为此,在评价基金业绩时有必要将协偏度风险... 协偏度度量一项资产对市场尾部风险的贡献,是一种重要的系统性风险,亦是资产定价中的重要变量之一。在基金管理中,基金经理可通过投资负协偏度资产来承担协偏度风险,进而获取协偏度风险溢价。为此,在评价基金业绩时有必要将协偏度风险溢价从基金Alpha收益中区分出来,以免误判基金经理获得超额收益的能力。本文构建能捕捉未来协偏度风险的前瞻协偏度因子,将其引入传统多因子模型,并基于2004—2023年我国开放式权益型基金样本,检验协偏度对基金业绩的影响。结果表明:(1)前瞻协偏度因子对基金收益具有显著的解释力,以Fama-French五因子模型为例,协偏度因子对基金收益的解释力仅次于市场因子和价值因子。(2)价值型基金规避了协偏度风险,在考虑协偏度因素后获得业绩奖励,基金业绩明显改善;中小盘基金承担了更多协偏度风险,在考虑协偏度因素后获得业绩惩罚,基金业绩显著下降。(3)基金的协偏度策略具有持续性,前期承担较大协偏度风险的基金,在后期仍然会承担较高的协偏度风险。(4)协偏度风险较高的基金往往更年轻、管理费率更高、持有的资产更缺乏流动性、机构投资者的持有比例更低。本文拓展了基金业绩评价的相关研究,为基金公司构建更科学的评价体系、投资者做出合理投资决策提供了参考。 展开更多
关键词 协偏度 权益型基金 基金业绩 因子模型
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敲低Linc00052表达对成骨细胞增殖、迁移和凋亡的影响
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作者 齐鲁 王俊杰 +1 位作者 邓钦高 王星 《中国组织工程研究》 北大核心 2026年第12期2949-2956,共8页
背景:Linc00052与多种疾病的发生和发展密切相关,包括癌症和炎症性疾病。研究发现,Linc00052靶向miR-145发挥人关节软骨细胞损伤的保护作用。目的:观察敲低Linc00052对成骨细胞增殖、迁移和凋亡的影响方法:(1)收集30例人根尖周炎骨组织... 背景:Linc00052与多种疾病的发生和发展密切相关,包括癌症和炎症性疾病。研究发现,Linc00052靶向miR-145发挥人关节软骨细胞损伤的保护作用。目的:观察敲低Linc00052对成骨细胞增殖、迁移和凋亡的影响方法:(1)收集30例人根尖周炎骨组织与30例人健康根尖周骨组织,RT-qPCR检测Linc00052、miR-145表达。(2)将第3代CP-H111成骨细胞分2组培养:实验组转染慢病毒敲低Linc00052表达,对照组转染空载慢病毒阴性对照,转染72 h后,RT-qPCR检测Linc00052、miR-145表达,Western blot检测肿瘤坏死因子α与转化生长因子β/SMAD2/SMAD3信号通路蛋白表达,CCK-8实验检测细胞增殖,划痕实验、Transwell小室实验检测细胞迁移,流式细胞术检测细胞凋亡。结果与结论:(1)根尖周炎根尖周骨组织中Linc00052表达高于健康根尖周骨组织(P<0.05),miR-145表达低于健康根尖周骨组织(P<0.05);(2)实验组细胞内Linc00052表达、细胞凋亡与肿瘤坏死因子α蛋白表达低于对照组(P<0.05),miR-145表达与转化生长因子β1、p-SMAD2、p-SMAD3蛋白表达高于对照组,细胞迁移能力强于对照组;(3)结果表明,敲低Linc00052可通过负调控miR-145表达降低肿瘤坏死因子α蛋白表达、激活转化生长因子β/SMAD2/SMAD3信号通路,促进成骨细胞的增殖、迁移并抑制细胞凋亡。 展开更多
关键词 Linc00052 成骨细胞 肿瘤坏死因子Α 转化生长因子β/SMAD2/SMAD3信号通路 根尖周炎骨缺损
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Changes in border-associated macrophages after stroke: Single-cell sequencing analysis 被引量:1
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作者 Ning Yu Yang Zhao +3 位作者 Peng Wang Fuqiang Zhang Cuili Wen Shilei Wang 《Neural Regeneration Research》 2026年第1期346-356,共11页
Border-associated macrophages are located at the interface between the brain and the periphery, including the perivascular spaces, choroid plexus, and meninges. Until recently, the functions of border-associated macro... Border-associated macrophages are located at the interface between the brain and the periphery, including the perivascular spaces, choroid plexus, and meninges. Until recently, the functions of border-associated macrophages have been poorly understood and largely overlooked. However, a recent study reported that border-associated macrophages participate in stroke-induced inflammation, although many details and the underlying mechanisms remain unclear. In this study, we performed a comprehensive single-cell analysis of mouse border-associated macrophages using sequencing data obtained from the Gene Expression Omnibus(GEO) database(GSE174574 and GSE225948). Differentially expressed genes were identified, and enrichment analysis was performed to identify the transcription profile of border-associated macrophages. CellChat analysis was conducted to determine the cell communication network of border-associated macrophages. Transcription factors were predicted using the ‘pySCENIC' tool. We found that, in response to hypoxia, borderassociated macrophages underwent dynamic transcriptional changes and participated in the regulation of inflammatory-related pathways. Notably, the tumor necrosis factor pathway was activated by border-associated macrophages following ischemic stroke. The pySCENIC analysis indicated that the activity of signal transducer and activator of transcription 3(Stat3) was obviously upregulated in stroke, suggesting that Stat3 inhibition may be a promising strategy for treating border-associated macrophages-induced neuroinflammation. Finally, we constructed an animal model to investigate the effects of border-associated macrophages depletion following a stroke. Treatment with liposomes containing clodronate significantly reduced infarct volume in the animals and improved neurological scores compared with untreated animals. Taken together, our results demonstrate comprehensive changes in border-associated macrophages following a stroke, providing a theoretical basis for targeting border-associated macrophages-induced neuroinflammation in stroke treatment. 展开更多
关键词 border-associated macrophages CLODRONATE hypoxia ISCHEMIA-REPERFUSION ischemic stroke liposomes neuroinflammation single-cell sequencing analysis STAT3 tumor necrosis factor
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老年乳腺癌患者预后影响因素的研究进展
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作者 苏明 赵淑樱 +1 位作者 王晓玲 杨晓蓉 《公共卫生与预防医学》 2026年第1期146-149,共4页
乳腺癌是发生在乳房腺上皮组织的恶性肿瘤,是一种严重影响妇女身心健康的最常见的肿瘤之一。随着人口老龄化的加剧,近年来老年乳腺癌的发病率逐年增加。老年乳腺癌患者常合并多种基础疾病,其预后通常与癌症分期、癌症分型、治疗情况、... 乳腺癌是发生在乳房腺上皮组织的恶性肿瘤,是一种严重影响妇女身心健康的最常见的肿瘤之一。随着人口老龄化的加剧,近年来老年乳腺癌的发病率逐年增加。老年乳腺癌患者常合并多种基础疾病,其预后通常与癌症分期、癌症分型、治疗情况、健康状况等多种因素有关,患者间生存率可能存在较大差异。由于老年乳腺癌患者相较中青年患者具有独特的临床和病理特点,既往综述多集中于探讨老年乳腺癌患者治疗方式的研究进展。基于此,此文根据既往学者研究成果从临床病理特征、治疗方式选择、影响预后的独立因素等方面对老年乳腺癌患者预后影响因素的研究进展进行综述,以期未来为临床选择老年乳腺癌患者的诊疗方案提供参考依据。 展开更多
关键词 老年乳腺癌 预后 影响因素
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基于miR-106b-5p/BTG3轴探讨胃衡汤对甲基硝基亚硝基胍诱导胃癌前病变小鼠的效应机制
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作者 姜正艳 陈璇 +4 位作者 郑亮 李镇 王渊 陆贤燕 《陕西中医》 2026年第1期3-9,共7页
目的:探讨胃衡汤对甲基硝基亚硝基胍(MNNG)诱导的胃癌前病变(PLGC)小鼠的治疗作用及对miR-106b-5p/BTG3轴的调控机制。方法:采用MNNG联合饥饱失常法建立PLGC小鼠模型。将60只小鼠随机分为空白组、模型组、胃衡汤低、中、高剂量组及胃复... 目的:探讨胃衡汤对甲基硝基亚硝基胍(MNNG)诱导的胃癌前病变(PLGC)小鼠的治疗作用及对miR-106b-5p/BTG3轴的调控机制。方法:采用MNNG联合饥饱失常法建立PLGC小鼠模型。将60只小鼠随机分为空白组、模型组、胃衡汤低、中、高剂量组及胃复春组,每组各10只。通过HE染色观察胃黏膜病理变化;ELISA法检测肿瘤坏死因子-α(TNF-α)、白细胞介素-6(IL-6)、白细胞介素-1β(IL-1β)、白细胞介素-10(IL-10)、转化生长因子-β(TGF-β)表达水平;Western blot检测BTG3、Ki67、Bax及Caspase蛋白表达;扫描电镜观察超微结构;RT-qPCR检测miR-106b-5p表达,并验证其与BTG3的靶向关系。结果:胃衡汤可显著改善PLGC小鼠胃黏膜萎缩、肠化生及炎症浸润等病理表现。与模型组相比,胃衡汤可显著降低促炎因子TNF-α、IL-6、IL-1β的表达水平,并升高抗炎因子IL-10水平;显著抑制miR-106b-5p表达,上调其靶基因BTG3蛋白表达,同时降低增殖标志物Ki67表达,促进凋亡蛋白Bax及Caspase-3、Caspase-9的表达,且呈剂量依赖性,高剂量效果最显著。结论:胃衡汤可能通过下调miR-106b-5p/BTG3,解除其对靶基因BTG3的抑制,从而激活BTG3介导的信号通路,抑制炎症反应、促进细胞凋亡并抑制异常增殖,达到改善PLGC的作用。 展开更多
关键词 胃癌前病变 胃衡汤 肿瘤坏死因子-Α 白细胞介素-6 转化生长因子-Β
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顺北—顺南地区深层碳酸盐岩走滑断裂结构特征及其形成的主控因素分析
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作者 吴孔友 杨言军 +2 位作者 刘寅 洪梅 汪必峰 《浙江大学学报(理学版)》 北大核心 2026年第1期97-108,共12页
塔里木盆地顺北—顺南地区的深层碳酸盐岩走滑断裂发育对下古生界碳酸盐岩具有明显的控藏作用。由于碳酸盐岩岩性脆且致密,走滑断裂水平错动作用必然导致其形成独特的结构特征。针对顺北—顺南地区的深层碳酸盐岩走滑断裂体系,基于现有... 塔里木盆地顺北—顺南地区的深层碳酸盐岩走滑断裂发育对下古生界碳酸盐岩具有明显的控藏作用。由于碳酸盐岩岩性脆且致密,走滑断裂水平错动作用必然导致其形成独特的结构特征。针对顺北—顺南地区的深层碳酸盐岩走滑断裂体系,基于现有研究成果,通过野外相似露头踏勘,结合地震、岩心等资料,利用高精度三维地震数据体走滑断裂精细刻画、地震属性体走滑断裂体系识别、物理模拟实验、应力场数值模拟等技术方法,分析了走滑断裂的结构特征,并对其形成的主控因素进行了归纳总结。研究发现,顺北—顺南地区深层走滑断裂的空间结构主要表现为“平面沿走向分段、剖面分层变形”的特征,在平面上主断裂可划分为张扭段、压扭段、直立段,三者交替出现,在剖面上以中下奥陶统顶界面(T74)为界,将断裂分为深层和浅层系统,深、浅层断裂纵向叠置,分层特征明显。将内部结构划分为“滑动破碎带—诱导裂缝带”二元结构,二者差异明显,特征相异。多期构造活动、应力分布、断裂活动强度、地层岩性和后期的胶结充填作用均可影响断裂带的二元结构。 展开更多
关键词 塔里木盆地 碳酸盐岩 走滑断裂 结构特征 控制因素
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