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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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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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Health risk assessment of trace metal(loid)s in agricultural soils based on Monte Carlo simulation coupled with positive matrix factorization model in Chongqing, southwest China 被引量:4
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作者 MA Jie CHU Lijuan +3 位作者 SUN Jing WANG Shenglan GE Miao DENG Li 《Journal of Mountain Science》 SCIE CSCD 2024年第1期100-112,共13页
This study aimed to investigate the pollution characteristics, source apportionment, and health risks associated with trace metal(loid)s(TMs) in the major agricultural producing areas in Chongqing, China. We analyzed ... This study aimed to investigate the pollution characteristics, source apportionment, and health risks associated with trace metal(loid)s(TMs) in the major agricultural producing areas in Chongqing, China. We analyzed the source apportionment and assessed the health risk of TMs in agricultural soils by using positive matrix factorization(PMF) model and health risk assessment(HRA) model based on Monte Carlo simulation. Meanwhile, we combined PMF and HRA models to explore the health risks of TMs in agricultural soils by different pollution sources to determine the priority control factors. Results showed that the average contents of cadmium(Cd), arsenic (As), lead(Pb), chromium(Cr), copper(Cu), nickel(Ni), and zinc(Zn) in the soil were found to be 0.26, 5.93, 27.14, 61.32, 23.81, 32.45, and 78.65 mg/kg, respectively. Spatial analysis and source apportionment analysis revealed that urban and industrial sources, agricultural sources, and natural sources accounted for 33.0%, 27.7%, and 39.3% of TM accumulation in the soil, respectively. In the HRA model based on Monte Carlo simulation, noncarcinogenic risks were deemed negligible(hazard index <1), the carcinogenic risks were at acceptable level(10^(-6)<total carcinogenic risk ≤ 10^(-4)), with higher risks observed for children compared to adults. The relationship between TMs, their sources, and health risks indicated that urban and industrial sources were primarily associated with As, contributing to 75.1% of carcinogenic risks and 55.7% of non-carcinogenic risks, making them the primary control factors. Meanwhile, agricultural sources were primarily linked to Cd and Pb, contributing to 13.1% of carcinogenic risks and 21.8% of non-carcinogenic risks, designating them as secondary control factors. 展开更多
关键词 Monte Carlo simulation Health risk assessment Trace metal(loid)s Positive matrix factorization Agricultural soils
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NFA:A neural factorization autoencoder based online telephony fraud detection
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作者 Abdul Wahid Mounira Msahli +1 位作者 Albert Bifet Gerard Memmi 《Digital Communications and Networks》 SCIE CSCD 2024年第1期158-167,共10页
The proliferation of internet communication channels has increased telecom fraud,causing billions of euros in losses for customers and the industry each year.Fraudsters constantly find new ways to engage in illegal ac... The proliferation of internet communication channels has increased telecom fraud,causing billions of euros in losses for customers and the industry each year.Fraudsters constantly find new ways to engage in illegal activity on the network.To reduce these losses,a new fraud detection approach is required.Telecom fraud detection involves identifying a small number of fraudulent calls from a vast amount of call traffic.Developing an effective strategy to combat fraud has become challenging.Although much effort has been made to detect fraud,most existing methods are designed for batch processing,not real-time detection.To solve this problem,we propose an online fraud detection model using a Neural Factorization Autoencoder(NFA),which analyzes customer calling patterns to detect fraudulent calls.The model employs Neural Factorization Machines(NFM)and an Autoencoder(AE)to model calling patterns and a memory module to adapt to changing customer behaviour.We evaluate our approach on a large dataset of real-world call detail records and compare it with several state-of-the-art methods.Our results show that our approach outperforms the baselines,with an AUC of 91.06%,a TPR of 91.89%,an FPR of 14.76%,and an F1-score of 95.45%.These results demonstrate the effectiveness of our approach in detecting fraud in real-time and suggest that it can be a valuable tool for preventing fraud in telecommunications networks. 展开更多
关键词 Telecom industry Streaming anomaly detection Fraud analysis factorization machine Real-time system Security
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Efficient Clustering Network Based on Matrix Factorization
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作者 Jieren Cheng Jimei Li +2 位作者 Faqiang Zeng Zhicong Tao and Yue Yang 《Computers, Materials & Continua》 SCIE EI 2024年第7期281-298,共18页
Contrastive learning is a significant research direction in the field of deep learning.However,existing data augmentation methods often lead to issues such as semantic drift in generated views while the complexity of ... Contrastive learning is a significant research direction in the field of deep learning.However,existing data augmentation methods often lead to issues such as semantic drift in generated views while the complexity of model pre-training limits further improvement in the performance of existing methods.To address these challenges,we propose the Efficient Clustering Network based on Matrix Factorization(ECN-MF).Specifically,we design a batched low-rank Singular Value Decomposition(SVD)algorithm for data augmentation to eliminate redundant information and uncover major patterns of variation and key information in the data.Additionally,we design a Mutual Information-Enhanced Clustering Module(MI-ECM)to accelerate the training process by leveraging a simple architecture to bring samples from the same cluster closer while pushing samples from other clusters apart.Extensive experiments on six datasets demonstrate that ECN-MF exhibits more effective performance compared to state-of-the-art algorithms. 展开更多
关键词 Contrastive learning CLUSTERING matrix factorization
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Symmetric Nonnegative Matrix Factorization for Vertex Centrality in Complex Networks
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作者 LU Pengli CHEN Wei +1 位作者 GUO Yuhong CHEN Yahong 《Journal of Shanghai Jiaotong university(Science)》 2024年第6期1037-1049,共13页
One of the most important problems in complex networks is to identify the influential vertices for understanding and controlling of information diffusion and disease spreading.Most of the current centrality algorithms... One of the most important problems in complex networks is to identify the influential vertices for understanding and controlling of information diffusion and disease spreading.Most of the current centrality algorithms focus on single feature or manually extract the attributes,which occasionally results in the failure to fully capture the vertex’s importance.A new vertex centrality approach based on symmetric nonnegative matrix factorization(SNMF),called VCSNMF,is proposed in this paper.For highlight the characteristics of a network,the adjacency matrix and the degree matrix are fused to represent original data of the network via a weighted linear combination.First,SNMF automatically extracts the latent characteristics of vertices by factorizing the established original data matrix.Then we prove that each vertex’s composite feature which is constructed with one-dimensional factor matrix can be approximated as the term of eigenvector associated with the spectral radius of the network,otherwise obtained by the factor matrix on the hyperspace.Finally,VCSNMF integrates the composite feature and the topological structure to evaluate the performance of vertices.To verify the effectiveness of the VCSNMF criterion,eight existing centrality approaches are used as comparison measures to rank influential vertices in ten real-world networks.The experimental results assert the superiority of the method. 展开更多
关键词 complex networks CENTRALITY symmetric nonnegative matrix factorization(SNMF)
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戊糖片球菌CQFP202437对抗生素诱导小鼠运动机能失调的调节作用机制
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作者 李科 易若琨 《食品工业科技》 北大核心 2025年第10期383-390,共8页
本研究旨在探究戊糖片球菌CQFP202437对抗生素诱导小鼠运动失调的保护作用,探讨益生菌的作用效果和机理。使用无菌处理后的混合抗生素溶液腹腔注射构建小鼠运动失调模型,造模结束后测定各组小鼠跑步和游泳等运动参数的变化以及小鼠血清... 本研究旨在探究戊糖片球菌CQFP202437对抗生素诱导小鼠运动失调的保护作用,探讨益生菌的作用效果和机理。使用无菌处理后的混合抗生素溶液腹腔注射构建小鼠运动失调模型,造模结束后测定各组小鼠跑步和游泳等运动参数的变化以及小鼠血清和脑组织中丙二醛(Malondialdehyde,MDA),超氧化物歧化酶(Superoxide Dismutase,SOD)、还原型谷胱甘肽(Reduced Glutathione,GSH),小鼠白细胞介素(Interleukin-6,IL-6、Interleukin-10,IL-10)和肿瘤坏死因子(Tumor Necrosis Factor-α,TNF-α);小鼠盲肠肠道屏障基因Occludin-1、ZO-1和Claudin-1的mRNA相对表达量;小鼠脑组织中CREB、ERK1/2和BDNF基因的mRNA相对表达量。结果显示,与模型组相比,戊糖片球菌CQFP202437显著提升了小鼠游泳和跑步的时间(P<0.01),显著(P<0.05)降低小鼠大脑中炎症因子IL-6、TNF-α的水平,增加小鼠大脑中SOD的表达,减少小鼠大脑和血清中MDA的累积。并且戊糖片球菌CQFP202437能提升小鼠大脑组织中BDNF代谢通路相关基因BDNF、ERK1/2、CREB的表达,增强BDNF的作用,还能上调盲肠组织中Occludin-1基因表达。结果表明,戊糖片球菌CQFP202437对抗生素诱导小鼠运动机能失调有调节作用,为提升运动机能益生菌制剂的研制和开发提供理论依据。 展开更多
关键词 戊糖片球菌 跑台运动 负重游泳 脑源性神经因子(Brain Derived Neurophic Factor BDNF)
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不同激活剂对富血小板血浆生长因子的影响 被引量:4
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作者 刘建香 冯星星 +3 位作者 王淑霞 周蓉 吕孟兴 屈柯暄 《中国组织工程研究》 CAS 北大核心 2025年第10期2067-2073,共7页
背景:生长因子是富血小板血浆在临床治疗中发挥作用的关键效应分子,不同激活剂激活富血小板血浆后生长因子浓度存在差异,是影响临床疗效的重要因素。目的:分析不同激活剂对富血小板血浆中生长因子质量浓度的影响。方法:招募12名健康志愿... 背景:生长因子是富血小板血浆在临床治疗中发挥作用的关键效应分子,不同激活剂激活富血小板血浆后生长因子浓度存在差异,是影响临床疗效的重要因素。目的:分析不同激活剂对富血小板血浆中生长因子质量浓度的影响。方法:招募12名健康志愿者,采集EDTA-K2抗凝静脉血,应用二次离心法制备富血小板血浆。比较静脉血与富血小板血浆中生长因子的质量浓度差异。将富血小板血浆分别与4种激活剂(生理盐水、凝血酶、葡萄糖酸钙、葡萄糖酸钙+凝血酶)按照体积比10∶1混匀,置于37℃恒温水浴箱孵育30 min,离心后提取上清液,检测生长因子质量浓度;利用血琼脂平板检测上清液中的细菌生长情况;采用Pearson相关分析不同激活剂与富血小板血浆中生长因子质量浓度的相关性,血小板计数值与富血小板血浆中生长因子质量浓度的相关性。结果与结论:(1)富血小板血浆中血小板衍生生长因子BB、血小板衍生生长因子AB、血管内皮生长因子、表皮生长因子的质量浓度分别是静脉血中对应生长因子质量浓度的8.7,22.2,2.3,2.8倍(P <0.05);(2)与生理盐水组比较,凝血酶组、葡萄糖酸钙组、葡萄糖酸钙+凝血酶组中血小板衍生生长因子BB、血小板衍生生长因子AB、血管内皮生长因子、表皮生长因子质量浓度升高(P <0.05);凝血酶组、葡萄糖酸钙组血小板衍生生长因子BB质量浓度高于葡萄糖酸钙+凝血酶组(P <0.05),凝血酶组血小板衍生生长因子AB质量浓度高于葡萄糖酸钙组、葡萄糖酸钙+凝血酶组(P <0.05),凝血酶组表皮生长因子质量浓度低于葡萄糖酸钙组、葡萄糖酸钙+凝血酶组(P <0.05);(3)血琼脂平板实验结果显示4组上清液中均无细菌生长;(4)Pearson相关分析显示,富血小板血浆中血小板衍生生长因子BB质量浓度与凝血酶存在正向强相关性(r=0.683,P <0.05),血管内皮生长因子质量浓度与凝血酶、葡萄糖酸钙、葡萄糖酸钙+凝血酶激混合剂存在正向强相关性(r=0.730,0.789,0.686,P <0.05);富血小板中血小板计数值与4种生长因子质量浓度均无相关性(P> 0.05);(5)结果提示,不同激活剂对富血小板血浆中生长因子浓度产生不同影响,建议临床根据不同生长因子质量浓度和治疗需求选择不同激活剂,以提高临床疗效。 展开更多
关键词 富血小板血浆 凝血酶 葡萄糖酸钙 血小板衍生生长因子BB 血小板衍生生长因子AB 血管内皮生长因子 表皮生长因子
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妊娠晚期缺铁性贫血的危险因素和列线图预测模型 被引量:3
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作者 杨林 王亦雄 +1 位作者 潘辉 徐扬 《中山大学学报(医学科学版)》 北大核心 2025年第1期116-122,共7页
【目的】对孕妇妊娠期缺铁性贫血(IDA)的相关因素进行分析,根据其独立的危险因素,构建预测妊娠晚期缺铁性贫血的列线图预测模型,以期获得IDA的有效干预方案。【方法】将2022年7月—2023年12月在扬州市妇幼保健院定期产检的孕妇为调查对... 【目的】对孕妇妊娠期缺铁性贫血(IDA)的相关因素进行分析,根据其独立的危险因素,构建预测妊娠晚期缺铁性贫血的列线图预测模型,以期获得IDA的有效干预方案。【方法】将2022年7月—2023年12月在扬州市妇幼保健院定期产检的孕妇为调查对象,采取统一调查问卷结合监测血常规的方法跟踪孕妇直至分娩,入组500例,最终完成482例。根据孕晚期有无IDA分为IDA组与非IDA组。对可能影响缺铁性贫血的危险因素进行单因素分析及多因素logistic回归分析,并采用R软件建立预测发生的列线图模型。【结果】482例妊娠晚期女性发生IDA有96例,发生率为19.92%;单因素分析显示,经济独立情况、孕前体质指数、孕次及孕期有无正规补铁与妊娠晚期IDA的发生有关,差异均有统计学意义(P<0.05)。多因素Logistic回归分析显示,经济独立(P=0.031,OR=0.583)、孕期正规补铁(P<0.001,OR=5.337)是IDA的保护因素;孕前低体质指数(P=0.021,OR=2.375),孕次≥3次(P=0.015,OR=2.253)是IDA的危险因素。ROC曲线显示,列线图模型预测IDA发生的曲线下面积为0.84,最佳截断值为-1.481,预测灵敏度为81.2%,特异度分别为75.1%。【结论】妊娠晚期IDA发病率较高;孕前低体质指数、孕次大于3次是妊娠晚期IDA的危险因素;经济独立、正规补铁是妊娠晚期IDA的保护因素。可利用上述因素构建预测模型、采取预防性措施研究降低妊娠晚期IDA发病率的可行性方案。 展开更多
关键词 妊娠晚期 缺铁性贫血 危险因素 保护因素 列线图 预测模型
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数字经济与农业全要素生产率:技术进步和要素流动的视角 被引量:9
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作者 龚勤林 乔涛 冷玉婷 《华中农业大学学报(社会科学版)》 北大核心 2025年第2期15-27,共13页
在持续提高农业创新力、竞争力和全要素生产率的背景下,利用2011−2019年中国273个地级市面板数据,实证检验了数字经济对农业全要素生产率的影响。研究结论如下:第一,数字经济发展能够显著提升农业全要素生产率;第二,技术进步和要素流动... 在持续提高农业创新力、竞争力和全要素生产率的背景下,利用2011−2019年中国273个地级市面板数据,实证检验了数字经济对农业全要素生产率的影响。研究结论如下:第一,数字经济发展能够显著提升农业全要素生产率;第二,技术进步和要素流动是数字经济影响农业全要素生产率的作用机制,具体包括农业技术进步、农业劳动力转移、农用耕地流转与农业资本深化;第三,数字经济作用存在异质性,其对我国西部地区农业全要素生产率提升作用不显著,且由于粮食主产区的萎缩与限制政策,数字经济带来的农业劳动力转移与农业资本深化效应会受到抑制。基于此,文章认为政府应当推动农业基础设施数字化、助力降低数字技术使用门槛、以数字赋能农业科技创新与应用、健全农地流转管理体制,强化粮食主产区农业支持政策等。 展开更多
关键词 数字经济 技术进步 要素流动 农业全要素生产率
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某大型三甲医院门诊患者满意度调查及影响因素分析 被引量:7
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作者 房洪军 王浩 +3 位作者 李晶 杨宏艳 关思楠 李航 《中国医院管理》 北大核心 2025年第2期40-45,共6页
目的 分析某大型三甲公立医院多院区门诊患者就医体验满意度。方法 2024年1—3月,基于问卷星平台向北京大学第一医院门诊当日就诊患者推送门诊就诊满意度调查问卷,分析门诊患者对医疗服务的满意率和满意度评分,并采用logistic回归分析... 目的 分析某大型三甲公立医院多院区门诊患者就医体验满意度。方法 2024年1—3月,基于问卷星平台向北京大学第一医院门诊当日就诊患者推送门诊就诊满意度调查问卷,分析门诊患者对医疗服务的满意率和满意度评分,并采用logistic回归分析探索门诊患者就诊满意度的影响因素。结果 64.0%认为非常满意,26.1%认为比较满意;候诊时长和就诊时长发挥重要影响作用;医生的疾病诊断、治疗和预后、健康宣教和随诊安排可能会影响门诊患者就诊体验;门诊缴费、门诊环境、门诊患者感知抱怨及不满的及时解决都影响门诊患者就诊满意度。结论 门诊患者整体满意度较高,多院区门诊医疗服务患者满意度保持一致。医院应在保证门诊医疗质量的前提下,积极进行个体化健康教育,优化就医流程,延伸门诊服务,进一步提升门诊患者就医获得感。 展开更多
关键词 三甲医院 门诊患者 满意度 影响因素
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基于Nrf2/GPX4通路调控铁死亡探讨黄连解毒汤对动脉粥样硬化小鼠的影响 被引量:8
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作者 龚兆会 高黎 +6 位作者 翟惠奇 余锦紫 褚庆民 罗川晋 卿立金 吴伟 李荣 《中国实验方剂学杂志》 北大核心 2025年第3期22-28,共7页
目的:研究黄连解毒汤通过改善铁死亡治疗动脉粥样硬化(AS)小鼠的作用机制。方法:取SPF级C57BL/6J小鼠10只为正常组,另取载脂蛋白E敲除(ApoE^(-/-))小鼠50只随机分为5组,分别为模型组、黄连解毒汤低、中、高剂量组和阿托伐他汀组(ATV组)... 目的:研究黄连解毒汤通过改善铁死亡治疗动脉粥样硬化(AS)小鼠的作用机制。方法:取SPF级C57BL/6J小鼠10只为正常组,另取载脂蛋白E敲除(ApoE^(-/-))小鼠50只随机分为5组,分别为模型组、黄连解毒汤低、中、高剂量组和阿托伐他汀组(ATV组)。ApoE^(-/-)小鼠采用高脂饲料喂食8周构建AS模型,并在第9周开始分别予生理盐水,黄连解毒汤低、中、高剂量(3.9、7.8、15.6 g·kg^(-1)·d^(-1))和阿托伐他汀钙片(0.01 g·kg^(-1)·d^(-1))灌胃,共给药8周。采用大体油红O染色和马松(Masson)染色观察小鼠主动脉斑块的形成情况,自动生化分析仪测定血脂四项总胆固醇(TC)、低密度脂蛋白胆固醇(LDL-C)、甘油三酯(TG)、高密度脂蛋白胆固醇(HDL-C)水平,透射电镜观察主动脉线粒体结构,酶联免疫吸附测定法(ELISA)检测血清中超氧化物歧化酶(SOD)水平,微板法检测血清中还原型谷胱甘肽(GSH)含量,TBA法检测血清中丙二醛(MDA)含量,蛋白免疫印迹法检测小鼠主动脉核因子E_(2)相关因子2(Nrf2)/谷胱甘肽过氧化物酶4(GPX4)信号通路蛋白表达。结果:与正常组比较,模型组主动脉管腔斑块沉积,血清TC、LDL-C、TG、HDL-C、MDA含量显著升高(P<0.01),血清SOD、GSH和主动脉Nrf2、溶质载体家族7成员11(SLC7A11)、GPX4的表达水平均显著降低(P<0.01),主动脉线粒体碎裂、空泡化、体积萎缩,线粒体内嵴减少或者呈现松散、紊乱的形态。与模型组比较,黄连解毒汤低、中、高剂量组和ATV组主动脉管腔斑块沉积明显减少,小鼠血清TC、LDL-C、TG和MDA含量明显降低(P<0.05,P<0.01),血清SOD、GSH水平和主动脉Nrf2、SLC7A11、GPX4的表达水平升高(P<0.05,P<0.01),主动脉线粒体空泡化症状减轻,嵴数量增多且排序整齐。结论:黄连解毒汤能减轻AS小鼠主动脉管腔斑块沉积,降低血脂和MDA表达,升高SOD和GSH表达,改善铁死亡病理改变,其作用机制与Nrf2/GPX4信号通路有关。 展开更多
关键词 黄连解毒汤 动脉粥样硬化 铁死亡 核因子E_(2)相关因子2(Nrf2)/谷胱甘肽过氧化物酶4(GPX4)信号通路
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ATF3通过NF-κB信号通路调控动脉粥样硬化斑块内的炎症反应 被引量:1
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作者 夏冰 彭进 +6 位作者 丁九阳 王杰 唐国伟 刘国杰 王沄 万昌武 乐翠云 《南方医科大学学报》 北大核心 2025年第6期1131-1142,共12页
目的 探讨转录激活因子3(ATF3)在动脉粥样硬化斑块内的表达及其调控炎症反应参与动脉粥样硬化(AS)进程的机制。方法 收集尸检案例中的人冠状动脉标本,免疫荧光和Western blotting检测ATF3蛋白表达及分布;高脂饮食12周后的载脂蛋白E基因... 目的 探讨转录激活因子3(ATF3)在动脉粥样硬化斑块内的表达及其调控炎症反应参与动脉粥样硬化(AS)进程的机制。方法 收集尸检案例中的人冠状动脉标本,免疫荧光和Western blotting检测ATF3蛋白表达及分布;高脂饮食12周后的载脂蛋白E基因敲除(ApoE-/-)小鼠尾静脉注射9型腺相关病毒(AAV9)敲低ATF3的表达,继续高脂喂养5周构建ATF3基因敲除的动脉粥样硬化ApoE-/-小鼠模型。麻醉处死后观察主动脉斑块结构改变,检测斑块内ATF3、炎症相关因子及NF-κB信号通路蛋白表达改变,并在体外构建ATF3的过表达质粒及siRNA干预THP-1诱导的泡沫细胞模型验证ATF3与NF-κB信号通路间关系。结果 在人冠状动脉粥样硬化斑块内,ATF3的表达增高(P<0.05),且与CD68呈部分共表达;在ATF3基因敲除后,小鼠的主动脉斑块体积增大(P<0.05),斑块内炎症相关因子(CD45、CD68、IL-1β、TNF-α)表达增强(P<0.05),NF-κB信号通路相关蛋白(PIKKα/β、P-NF-κB p65)表达增高(P<0.05),VCAM1、MMP9及MMP2表达增强(P<0.05);在离体THP-1细胞实验中验证了沉默ATF3后NF-κB信号通路进一步激活,而过表达ATF3后NF-κB信号受到抑制。结论 动脉粥样硬化诱导ATF3的表达,ATF3的缺乏会促进AS的发生,增强斑块内炎症反应,其机制可能是通过进一步激活NF-κB信号通路导致,ATF3可能是AS潜在的治疗靶点。 展开更多
关键词 动脉粥样硬化 转录激活因子3 炎症反应 NF-ΚB 冠心病猝死
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乡村教师数字素养提升的影响因素与实施策略研究——基于结构方程与模糊集定性比较分析 被引量:7
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作者 吴军其 刘萌 +2 位作者 吴飞燕 龚蕾 徐慧 《中国电化教育》 北大核心 2025年第1期109-116,125,共9页
乡村教师的数字素养水平是影响乡村教育数字化转型效果的关键因素。已有的研究大多基于外部环境探究影响乡村教师数字素养提升的因素,较少从教师主体视角进行剖析。研究从乡村教师个人动机视角出发,基于UTAUT模型和自我决定理论构建乡... 乡村教师的数字素养水平是影响乡村教育数字化转型效果的关键因素。已有的研究大多基于外部环境探究影响乡村教师数字素养提升的因素,较少从教师主体视角进行剖析。研究从乡村教师个人动机视角出发,基于UTAUT模型和自我决定理论构建乡村教师数字素养提升的影响因素模型,采用结构方程模型(SEM)和模糊集定性比较分析(fsQCA)相结合的方法探究乡村教师数字素养提升的影响因素。SEM分析发现,乡村教师的绩效期望、努力期望、社会影响、内在动机正向显著影响数字素养提升意向,提升意向和便利条件正向显著影响数字素养,性别、教龄、学历对模型的部分路径具有调节作用;进一步通过fsQCA分析可知,绩效期望是影响乡村教师数字素养提升的必要条件,乡村教师数字素养提升的影响因素共有5种不同的组态。基于研究结果,提出从激发内生动力、满足绩效期望和差异化群体需求、提升便利条件感知等方面促进乡村教师数字素养提升。研究结论将为乡村教师数字素养提升和乡村教师专业发展提供思路和启发。 展开更多
关键词 乡村教师 数字素养 影响因素 结构方程 fsQCA
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逆向效应:政府引导基金异地投资与中小企业高质量发展 被引量:3
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作者 张倩倩 韩洁 张晓玫 《南开管理评论》 北大核心 2025年第8期148-158,共11页
政府引导基金由国有资本与社会资本共同出资设立,兼顾政策目标与经济利益的统一。然而,社会资本的逐利性可能驱使政府引导基金异地投资,偏离国有资本旨在支持本地企业发展的政策初衷。基于此,本文从“本地政策目标”与“经济利益”契合... 政府引导基金由国有资本与社会资本共同出资设立,兼顾政策目标与经济利益的统一。然而,社会资本的逐利性可能驱使政府引导基金异地投资,偏离国有资本旨在支持本地企业发展的政策初衷。基于此,本文从“本地政策目标”与“经济利益”契合的视角,使用新三板2010~2021年挂牌企业数据,分析政府引导基金异地投资所产生的经济后果是否偏离促进本地企业发展的政策目标。研究发现,政府引导基金异地投资提高了本地企业全要素生产率,实现了经济利益与政策目标共赢。机制分析表明,政府引导基金异地投资通过逆向技术溢出和引导产业集聚来促进企业发展,且该作用的发挥取决于政策扶持力度。进一步研究发现,欠发达地区政府引导基金的异地投资行为更能实现经济利益与政策目标共赢。此外,投资地理毗邻区域对本地企业发展的作用更明显,揭示了资本要素流动的距离衰退效应。本文创新性地从异地投资行为考察政府引导基金的实施效果,为理解政府引导基金异地投资的决策提供了理论证据。 展开更多
关键词 政府引导基金 异地投资 资本要素流动 全要素生产率 高质量发展
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全基因组选择技术在玉米育种中的应用 被引量:1
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作者 曹士亮 张学才 +6 位作者 张建国 扈光辉 于滔 曹靖生 杨耿斌 李文跃 马雪娜 《玉米科学》 北大核心 2025年第6期1-9,共9页
全基因组选择(Genomic selection或Genome-wide selection,GS)是指利用覆盖各染色体范围的分子标记对作物的表型进行的预测和选择。随着分子标记技术、数理统计的发展和计算机运算能力的提升,全基因组选择逐渐从理论走向实践,在作物种... 全基因组选择(Genomic selection或Genome-wide selection,GS)是指利用覆盖各染色体范围的分子标记对作物的表型进行的预测和选择。随着分子标记技术、数理统计的发展和计算机运算能力的提升,全基因组选择逐渐从理论走向实践,在作物种质资源创新和品种选育中发挥着越来越重要的作用,通过与常规育种的有效结合带来了育种方式的新飞跃。全基因组选择能够降低育种成本和加速育种进程,实现作物育种由鉴定育种向预测育种的转变。本文主要介绍全基因组选择技术产生的背景、应用流程和影响全基因组选择预测精度的因素,回顾和展望该技术在玉米种质创新和杂交组合预测上应用的现状与前景,提出当前开展玉米全基因组选择工作面临的问题和建议。 展开更多
关键词 玉米 全基因组选择 影响因素 展望
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