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Five-year conditional relative survival up to 10 years post-diagnosis among adolescent and young adult breast cancer patients by age,stage,and receptor subtype 被引量:1
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作者 Noëlle J.M.C.Vrancken Peeters Daniël J.van der Meer +5 位作者 Marleen Kok Marissa C.van Maaren Marie-Jeanne T.F.D.Vrancken Peeters Sabine Siesling Winette T.A.van der Graaf Olga Husson 《Journal of the National Cancer Center》 2025年第3期297-305,共9页
Background Conditional relative survival(CRS),the probability of survival given that an individual has already survived a certain period post-diagnosis,is a more clinically relevant measure for long-term survival than... Background Conditional relative survival(CRS),the probability of survival given that an individual has already survived a certain period post-diagnosis,is a more clinically relevant measure for long-term survival than standard relative survival(RS).This study aims to evaluate the 5-year CRS among adolescent and young adult(AYA)breast cancer patients by age,tumor stage,and receptor subtype to guide disclosure periods for insurance.Methods Data of all females aged 18–39 years and diagnosed with invasive breast cancer between 2003 and 2021(n=13,075)were obtained from The Netherlands Cancer Registry(NCR).The five-year CRS was calculated annually up to 10 years post-diagnosis using a hybrid analysis approach.Results For the total AYA breast cancer study population the 5-year CRS exceeded 90%from diagnosis and increased beyond 95%7 years post-diagnosis.Patients aged 18–24 reached 95%9 years post-diagnosis,those aged 25–29 after 5 years,and those aged 30–34 and 35–39 after 8 years.For stage I,the 5-year CRS reached 95%from diagnosis,for stage II after 6 years,while the 5-year CRS for stages III and IV did not reach the 95%threshold during the 10-year follow-up.Triple-negative tumors exceeded 95%after 4 years,human epidermal growth factor receptor 2(HER2)positive tumors after 6 years,while hormone receptor(HR)positive tumors did not reach 95%.Conclusion Excess mortality among AYA breast cancer patients tends to be little(CRS 90%–95%)from diagnosis and becomes minimal(CRS>95%)over time compared to the general population.These results can enhance expectation management and inform policymakers,suggesting a shorter disclosure period. 展开更多
关键词 Adolescents and young adults(AYAS) Breast cancer conditional relative survival(CRS) Excess mortality Relative survival(RS) SURVIVORSHIP
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Probabilistic Site Investigation Optimization of Gassy Soils Based on Conditional Random Field and Monte Carlo Simulation
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作者 Shaolin Ding 《World Journal of Engineering and Technology》 2025年第1期1-11,共11页
Gassy soils are distributed in relatively shallow layers the Quaternary deposit in Hangzhou Bay area. The shallow gassy soils significantly affect the construction of underground projects. Proper characterization of s... Gassy soils are distributed in relatively shallow layers the Quaternary deposit in Hangzhou Bay area. The shallow gassy soils significantly affect the construction of underground projects. Proper characterization of spatial distribution of shallow gassy soils is indispensable prior to construction of underground projects in the area. Due to the costly conditions required in the site investigation for gassy soils, only a limited number of gas pressure data can be obtained in engineering practice, which leads to the uncertainty in characterizing spatial distribution of gassy soils. Determining the number of boreholes for investigating gassy soils and their corresponding locations is pivotal to reducing construction risk induced by gassy soils. However, this primarily relies on the engineering experience in the current site investigation practice. This study develops a probabilistic site investigation optimization method for planning investigation schemes (including the number and locations of boreholes) of gassy soils based on the conditional random field and Monte Carlo simulation. The proposed method aims to provide an optimal investigation scheme before the site investigation based on prior knowledge. Finally, the proposed approach is illustrated using a case study. 展开更多
关键词 Gassy Soils Site Investigation UNCERTAINTY conditional Random Field Monte Carlo Simulation
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A FORMULA OF CONDITIONAL ENTROPY FOR METRICS INDUCED BY PROBABILITY BI-SEQUENCES
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作者 M.RAHIMI N.BIDABADI 《Acta Mathematica Scientia》 2025年第4期1619-1639,共21页
We study the conditional entropy of topological dynamical systems using a family of metrics induced by probability bi-sequences.We present a Brin-Katok formula by replacing the mean metric by a family of metrics induc... We study the conditional entropy of topological dynamical systems using a family of metrics induced by probability bi-sequences.We present a Brin-Katok formula by replacing the mean metric by a family of metrics induced by a probability bi-sequence.We also establish the Katok’s entropy formula for conditional entropy for ergodic measures in the case of the new family of metrics. 展开更多
关键词 ENTROPY conditional entropy probability bi-sequence
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Cross‑sectional anomalies and conditional asset pricing models based on investor sentiment: evidence from the Chinese stock market
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作者 Zhong‑Qiang Zhou Jiajia Wu +1 位作者 Ping Huang Xiong Xiong 《Financial Innovation》 2025年第1期2984-3007,共24页
This study examines a comprehensive set of 30 cross-sectional anomalies in the Chinese A-share market to investigate whether incorporating investor sentiment as conditioning information enhances the explanatory power ... This study examines a comprehensive set of 30 cross-sectional anomalies in the Chinese A-share market to investigate whether incorporating investor sentiment as conditioning information enhances the explanatory power of asset pricing models.Utilizing a long–short portfolio strategy and Fama–MacBeth cross-sectional regression,we find that trading-based anomalies outnumber accounting-based anomalies in the Chinese market.Our results demonstrate that conditional models significantly outperform their unconditional counterparts.Notably,investor sentiment is crucial for capturing the size anomaly when excluding observations from the COVID-19 pandemic period.Additionally,it substantially improves the ability of conditional Fama–French three-factor models to capture individual anomalies and enhances the return–prediction accuracy of conditional CAPMs.We suggest further investigating high-frequency investor sentiment-based conditional models to anticipate stock price fluctuations during extraordinary public health events. 展开更多
关键词 Cross-sectional anomalies conditional asset pricing Investor sentiment
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Weighted Attribute Based Conditional Proxy Re-Encryption in the Cloud
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作者 Xixi Yan Jing Zhang Pengyu Cheng 《Computers, Materials & Continua》 2025年第4期1399-1414,共16页
Conditional proxy re-encryption(CPRE)is an effective cryptographic primitive language that enhances the access control mechanism and makes the delegation of decryption permissions more granular,but most of the attribu... Conditional proxy re-encryption(CPRE)is an effective cryptographic primitive language that enhances the access control mechanism and makes the delegation of decryption permissions more granular,but most of the attribute-based conditional proxy re-encryption(AB-CPRE)schemes proposed so far do not take into account the importance of user attributes.A weighted attribute-based conditional proxy re-encryption(WAB-CPRE)scheme is thus designed to provide more precise decryption rights delegation.By introducing the concept of weight attributes,the quantity of system attributes managed by the server is reduced greatly.At the same time,a weighted tree structure is constructed to simplify the expression of access structure effectively.With conditional proxy re-encryption,large amounts of data and complex computations are outsourced to cloud servers,so the data owner(DO)can revoke the user’s decryption rights directly with minimal costs.The scheme proposed achieves security against chosen plaintext attacks(CPA).Experimental simulation results demonstrated that the decryption time is within 6–9 ms,and it has a significant reduction in communication and computation cost on the user side with better functionality compared to other related schemes,which enables users to access cloud data on devices with limited resources. 展开更多
关键词 Cloud service conditional proxy re-encryption user revocation weighted attribute
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FedCLCC:A personalized federated learning algorithm for edge cloud collaboration based on contrastive learning and conditional computing
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作者 Kangning Yin Xinhui Ji +1 位作者 Yan Wang Zhiguo Wang 《Defence Technology(防务技术)》 2025年第1期80-93,共14页
Federated learning(FL)is a distributed machine learning paradigm for edge cloud computing.FL can facilitate data-driven decision-making in tactical scenarios,effectively addressing both data volume and infrastructure ... Federated learning(FL)is a distributed machine learning paradigm for edge cloud computing.FL can facilitate data-driven decision-making in tactical scenarios,effectively addressing both data volume and infrastructure challenges in edge environments.However,the diversity of clients in edge cloud computing presents significant challenges for FL.Personalized federated learning(pFL)received considerable attention in recent years.One example of pFL involves exploiting the global and local information in the local model.Current pFL algorithms experience limitations such as slow convergence speed,catastrophic forgetting,and poor performance in complex tasks,which still have significant shortcomings compared to the centralized learning.To achieve high pFL performance,we propose FedCLCC:Federated Contrastive Learning and Conditional Computing.The core of FedCLCC is the use of contrastive learning and conditional computing.Contrastive learning determines the feature representation similarity to adjust the local model.Conditional computing separates the global and local information and feeds it to their corresponding heads for global and local handling.Our comprehensive experiments demonstrate that FedCLCC outperforms other state-of-the-art FL algorithms. 展开更多
关键词 Federated learning Statistical heterogeneity Personalized model conditional computing Contrastive learning
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Conditional relative survival:an essential tool for risk stratification of(breast)cancer patients
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作者 Luigino Dal Maso Annalisa Trama +1 位作者 Fabiola Giudici Stefano Guzzinati 《Journal of the National Cancer Center》 2025年第6期551-552,共2页
To the editor,The article by Vrancken Peeters and colleagues,1 showing updated five-year conditional relative survival(5-year CRS)for young breast cancer patients by relevant prognostic factors and longer follow-up th... To the editor,The article by Vrancken Peeters and colleagues,1 showing updated five-year conditional relative survival(5-year CRS)for young breast cancer patients by relevant prognostic factors and longer follow-up than previous European studies,2,3 has filled an important gap in knowledge for the most common cancer among young women. 展开更多
关键词 risk stratification breast cancer prognostic factors conditional relative survival young women
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Neural correlates of conditional reasoning dysfunction in major depression:An event-related potential study with the Wason selection task
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作者 Jia-Xv Li Mei-Chen Lu +7 位作者 Luo-An Wu Wei Li Yu Li Xin-Ping Li Xiao-Hong Liu Xue-Zheng Gao Zhen-He Zhou Hong-Liang Zhou 《World Journal of Psychiatry》 2025年第12期107-119,共13页
BACKGROUND Patients with major depression(MD)exhibit conditional reasoning dysfunction;however,no studies on the event-related potential(ERP)characteristics of conditional reasoning in MD have been reported.AIM To inv... BACKGROUND Patients with major depression(MD)exhibit conditional reasoning dysfunction;however,no studies on the event-related potential(ERP)characteristics of conditional reasoning in MD have been reported.AIM To investigate the ERP characteristics of conditional reasoning in MD patients and explore the neural mechanism of cognitive processing.METHODS Thirty-four patients with MD and 34 healthy controls(HCs)completed ERP measurements while performing the Wason selection task(WST).The clusterbased permutation test in FieldTrip was used to compare the differences in the mean amplitudes between the patients with MD and HCs on the ERP components under different experimental conditions.Behavioral data[accuracy(ACC)and reaction times(RTs)],the ERP P100 and late positive potentials(LPPs)were analyzed.RESULTS Although the mean ACC was greater and the mean of RTs was shorter in HCs than in MD patients,the differences were not statistically significant.However,across both groups,the ACC in the precautionary WST was greater than that in the other tasks,and the RTs in the abstract task were greater than those in the other tasks.Importantly,compared with that of HCs,the P100 of the left centroparietal sites was significantly increased,and the early LPP was attenuated at parietal sites and increased at left frontocentral sites;the medium LPP and late LPP were increased at the left frontocentral sites.CONCLUSION Patients with MD have conditional reasoning dysfunction and exhibit abnormal ERP characteristics evoked by the WST,which suggests neural correlates of abnormalities in conditional reasoning function in MD patients. 展开更多
关键词 Major depression Event-related potential Wason selection task conditional reasoning Neural mechanism
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An Extension of Conditional Nonlinear Optimal Perturbation in the Time Dimension and Its Applications in Targeted Observations
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作者 Ziqing ZU Mu MU +1 位作者 Jiangjiang XIA Qiang WANG 《Advances in Atmospheric Sciences》 2025年第9期1783-1797,共15页
The Conditional Nonlinear Optimal Perturbation(CNOP)method works essentially for conventional numerical models;however,it is not fully applicable to the commonly used deep-learning forecasting models(DLMs),which typic... The Conditional Nonlinear Optimal Perturbation(CNOP)method works essentially for conventional numerical models;however,it is not fully applicable to the commonly used deep-learning forecasting models(DLMs),which typically input multiple time slices without deterministic dependencies.In this study,the CNOP for DLMs(CNOP-DL)is proposed as an extension of the CNOP in the time dimension.This method is useful for targeted observations as it indicates not only where but also when to deploy additional observations.The CNOP-DL is calculated for a forecast case of sea surface temperature in the South China Sea with a DLM.The CNOP-DL identifies a sensitive area northwest of Palawan Island at the last input time.Sensitivity experiments demonstrate that the sensitive area identified by the CNOP-DL is effective not only for the CNOP-DL itself,but also for random perturbations.Therefore,this approach holds potential for guiding practical field campaigns.Notably,forecast errors are more sensitive to time than to location in the sensitive area.It highlights the crucial role of identifying the time of the sensitive area in targeted observations,corroborating the usefulness of extending the CNOP in the time dimension. 展开更多
关键词 deep-learning forecasting model conditional nonlinear optimal perturbation targeted observation sensitive area
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Optimal Receiver Operating Characteristic Curve of Classical Conditional Power under Normal Models
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作者 ZHANG Ying-Ying 《应用概率统计》 北大核心 2025年第2期277-304,共28页
A Receiver Operating Characteristic(ROC)analysis of a power is important and useful in clinical trials.A Classical Conditional Power(CCP)is a probability of a classical rejection region given values of true treatment ... A Receiver Operating Characteristic(ROC)analysis of a power is important and useful in clinical trials.A Classical Conditional Power(CCP)is a probability of a classical rejection region given values of true treatment effect and interim result.For hypotheses and reversed hypotheses under normal models,we obtain analytical expressions of the ROC curves of the CCP,find optimal ROC curves of the CCP,investigate the superiority of the ROC curves of the CCP,calculate critical values of the False Positive Rate(FPR),True Positive Rate(TPR),and cutoff of the optimal CCP,and give go/no go decisions at the interim of the optimal CCP.In addition,extensive numerical experiments are carried out to exemplify our theoretical results.Finally,a real data example is performed to illustrate the go/no go decisions of the optimal CCP. 展开更多
关键词 area under the curve(AUC) classical conditional power(CCP) go/no go decisions historical and interim data receiver operating characteristic(ROC)curve
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The evolving distribution of humidity conditional on temperature and implications for compound heat extremes across China in a warming world
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作者 Caixia Liang Jiacan Yuan 《Atmospheric and Oceanic Science Letters》 2025年第6期9-14,共6页
The likelihood of extreme heat occurrence is continuously increasing with global warming.Under high temperatures,humidity may exacerbate the heat impact on humanity.As atmospheric humidity depends on moisture availabi... The likelihood of extreme heat occurrence is continuously increasing with global warming.Under high temperatures,humidity may exacerbate the heat impact on humanity.As atmospheric humidity depends on moisture availability and is constrained by air temperature,it is important to project the changes in the distribution of atmospheric humidity conditional on air temperature as the climate continuously warms.Here,a non-crossing quantile smoothing spline is employed to build quantile regression models emulating conditional distributions of dew point(a measure of humidity)on local temperature evolving with escalating global mean surface temperature.By applying these models to 297 weather stations in seven regions in China,the study analyzes historical trends of humid-heat and dry-hot days,and projects their changes under global warming of 2.0℃ and 4.5℃.In response to global warming,rising trends of humid-heat extremes,while weakening trends of dry-hot extremes,are observed at most stations in Northeast China.Additionally,results indicate an increasing trend in dry-hot extremes at numerous stations across central China,but a rise in humid-heat extremes over Northwest China and coastal regions.These trends found in the current climate state are projected to intensify under 2.0℃ and 4.5℃ warming,possibly influenced by the heterogeneous variations in precipitation,soil moisture,and water vapor fluxes.Requiring much lower computational resources than coupled climate models,these quantile regression models can further project compound humidity and temperature extremes in response to different levels of global warming,potentially informing the risk management of compound humid-heat extremes on a local scale. 展开更多
关键词 Global warming conditional distribution of dew point on temperature Non-crossing quantile smoothing spline model Compound heat extremes
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Wavelet Transform-Based Bayesian Inference Learning with Conditional Variational Autoencoder for Mitigating Injection Attack in 6G Edge Network
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作者 Binu Sudhakaran Pillai Raghavendra Kulkarni +1 位作者 Venkata Satya Suresh kumar Kondeti Surendran Rajendran 《Computer Modeling in Engineering & Sciences》 2025年第10期1141-1166,共26页
Future 6G communications will open up opportunities for innovative applications,including Cyber-Physical Systems,edge computing,supporting Industry 5.0,and digital agriculture.While automation is creating efficiencies... Future 6G communications will open up opportunities for innovative applications,including Cyber-Physical Systems,edge computing,supporting Industry 5.0,and digital agriculture.While automation is creating efficiencies,it can also create new cyber threats,such as vulnerabilities in trust and malicious node injection.Denialof-Service(DoS)attacks can stop many forms of operations by overwhelming networks and systems with data noise.Current anomaly detection methods require extensive software changes and only detect static threats.Data collection is important for being accurate,but it is often a slow,tedious,and sometimes inefficient process.This paper proposes a new wavelet transformassisted Bayesian deep learning based probabilistic(WT-BDLP)approach tomitigate malicious data injection attacks in 6G edge networks.The proposed approach combines outlier detection based on a Bayesian learning conditional variational autoencoder(Bay-LCVariAE)and traffic pattern analysis based on continuous wavelet transform(CWT).The Bay-LCVariAE framework allows for probabilistic modelling of generative features to facilitate capturing how features of interest change over time,spatially,and for recognition of anomalies.Similarly,CWT allows emphasizing the multi-resolution spectral analysis and permits temporally relevant frequency pattern recognition.Experimental testing showed that the flexibility of the Bayesian probabilistic framework offers a vast improvement in anomaly detection accuracy over existing methods,with a maximum accuracy of 98.21%recognizing anomalies. 展开更多
关键词 Bayesian inference learning automaton convolutional wavelet transform conditional variational autoencoder malicious data injection attack edge environment 6G communication
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定量评估气象条件对滇池蓝藻水华发生的影响及预测
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作者 徐虹 戴丛蕊 +2 位作者 何雨芩 程晋昕 王玉尤婷 《水生态学杂志》 北大核心 2026年第2期89-96,共8页
对滇池蓝藻水华发生的可能性进行预测,为预防和开展藻华防治、保护水环境提供科学依据。基于2001―2021年逐日MODIS数据和随机森林算法,分别构建复苏期(3―6月)和高发期(7―12月)滇池蓝藻水华发生气象概率预测模型,并采用特征变量重要... 对滇池蓝藻水华发生的可能性进行预测,为预防和开展藻华防治、保护水环境提供科学依据。基于2001―2021年逐日MODIS数据和随机森林算法,分别构建复苏期(3―6月)和高发期(7―12月)滇池蓝藻水华发生气象概率预测模型,并采用特征变量重要性和偏依赖图定量评估了水华发生与气象因子之间的关系。结果表明:(1)近21年滇池蓝藻水华发生年累计频次和规模的均值分别为26.9次和7.30%,水华发生有明显的季节性特征。(2)影响水华发生的关键气象因子在复苏期为气温和风速,气温对水华发生的影响大于风速;高发期则为气温、风速、日照和降水,其中风速的影响最大,其次是气温,日照和降水的影响最小。(3)总体上,气温和降水会加剧蓝藻水华的发生,风速和日照则有抑制作用;气温、光照和降水对水华发生的影响具有一定的累积效应。(4)各因子对蓝藻水华的影响存在一定的适宜区间,超出或低于相应的区间可能会不利于水华的发生;当气温>18℃和风速<2.5 m/s时,发生水华的概率相对较高。(5)模型在复苏期的准确率、召回率、综合评价得分和受试者工作曲线下的面积值分别为80.1%、62.3%、63.4%和87.6%,而高发期为83.1%、85.2%、88.8%和86.0%。 展开更多
关键词 蓝藻水华 气象条件 出现概率 随机森林 滇池
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基于深度学习的双相不锈钢应力-应变场预测模型
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作者 邓彩艳 丁汉星 +2 位作者 马艳文 刘永 龚宝明 《天津大学学报(自然科学与工程技术版)》 北大核心 2026年第1期25-30,共6页
通过人工智能技术深度解析金属材料多尺度构效关系,构建基于深度学习的成分-工艺-性能高通量逆向设计范式,在材料研发的过程中具有重要作用.本研究提出了一种基于条件生成对抗网络(CGAN)的端到端深度学习模型,用于研究双相不锈钢微观组... 通过人工智能技术深度解析金属材料多尺度构效关系,构建基于深度学习的成分-工艺-性能高通量逆向设计范式,在材料研发的过程中具有重要作用.本研究提出了一种基于条件生成对抗网络(CGAN)的端到端深度学习模型,用于研究双相不锈钢微观组织与力学性能之间的关系.该模型结合了博弈论思想,通过整合双相不锈钢微观组织图像及仪器化压痕试验获取的相组织力学性能数据,实现了微观组织-性能关系的直接预测.模型数据库通过基于微观组织的有限元模拟方法构建,确保了训练数据的高保真性.结果表明,该模型能够直接从双相不锈钢的微观组织预测应力-应变场,其预测结果与有限元模拟和实验数据高度吻合. 展开更多
关键词 双相不锈钢 纳米压痕 条件生成对抗网络 微观组织 应力-应变场
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脐带间充质干细胞条件培养基对小型猪创伤性颅脑损伤组织修复的影响 被引量:1
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作者 崔连旭 李昊旻 +4 位作者 许峻荣 谭宝东 陆大鸿 彭四维 王进辉 《中国组织工程研究》 北大核心 2026年第7期1730-1735,共6页
背景:颅脑损伤是一种高发病率、高致残率及高致死率的常见创伤性疾病,目前缺乏有效的治疗方法,脐带间充质干细胞通过旁分泌途径为颅脑损伤治疗提供了新的研究方向。目的:探讨脐带间充质干细胞条件培养基对外力打击所致小型猪颅脑损伤的... 背景:颅脑损伤是一种高发病率、高致残率及高致死率的常见创伤性疾病,目前缺乏有效的治疗方法,脐带间充质干细胞通过旁分泌途径为颅脑损伤治疗提供了新的研究方向。目的:探讨脐带间充质干细胞条件培养基对外力打击所致小型猪颅脑损伤的治疗作用。方法:选取12头健康小型猪,随机分为模型组和实验组,每组6只,通过外力打击建立猪颅脑损伤模型,实验组造模后以微量注射泵将脐带间充质干细胞条件培养基注入脑损伤处周围4个点进行治疗。术后第1-14天,评价小型猪空间记忆能力;术后第5天,核磁共振扫描评价小型猪脑组织损伤、水肿情况;术后第14天,剖检小型猪脑组织损伤部位,进行苏木精-伊红染色,胶质纤维酸性蛋白、Iba1免疫组化染色和TUNEL染色,评价小型猪脑组织的损伤和修复情况。结果与结论:①实验组小型猪空间记忆能力评分与模型组相比无统计学差异(P>0.05);②术后第5天,两组小型猪脑部均出现明显的脑组织水肿信号,与模型组比较,实验组小型猪脑组织水肿范围缩小;③术后第14天,模型组小型猪损伤部位脑组织可见水肿、淤血、坏死,苏木精-伊红染色可见脑组织坏死,实验组小型猪损伤部位脑组织水肿较模型组减轻;④两组小型猪损伤部位脑组织均可见胶质纤维酸性蛋白和Iba1阳性表达,实验组胶质纤维酸性蛋白和Iba1阳性表达量均低于模型组;⑤TUNEL染色显示两组小型猪损伤部位脑组织均有细胞凋亡阳性表达,实验组凋亡细胞表达量低于模型组。结果表明,脐带间充质干细胞条件培养基通过减少脑组织水肿、降低脑组织炎症、减轻细胞凋亡,对小型猪颅脑损伤发挥治疗作用。 展开更多
关键词 脐带间充质干细胞 条件培养基 分泌组 颅脑损伤 神经修复 神经炎症 小型猪 工程化干细胞
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Semantic role labeling based on conditional random fields 被引量:9
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作者 于江德 樊孝忠 +1 位作者 庞文博 余正涛 《Journal of Southeast University(English Edition)》 EI CAS 2007年第3期361-364,共4页
Due to the fact that semantic role labeling (SRL) is very necessary for deep natural language processing, a method based on conditional random fields (CRFs) is proposed for the SRL task. This method takes shallow ... Due to the fact that semantic role labeling (SRL) is very necessary for deep natural language processing, a method based on conditional random fields (CRFs) is proposed for the SRL task. This method takes shallow syntactic parsing as the foundation, phrases or named entities as the labeled units, and the CRFs model is trained to label the predicates' semantic roles in a sentence. The key of the method is parameter estimation and feature selection for the CRFs model. The L-BFGS algorithm was employed for parameter estimation, and three category features: features based on sentence constituents, features based on predicate, and predicate-constituent features as a set of features for the model were selected. Evaluation on the datasets of CoNLL-2005 SRL shared task shows that the method can obtain better performance than the maximum entropy model, and can achieve 80. 43 % precision and 63. 55 % recall for semantic role labeling. 展开更多
关键词 semantic role labeling conditional random fields parameter estimation feature selection
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北京市西城区气象因素与猩红热发病关系的时间分层病例交叉研究
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作者 秦迪 马春娜 +2 位作者 魏孝侃 管秀刚 初艳慧 《公共卫生与预防医学》 2026年第1期83-87,共5页
目的探讨北京市西城区气象因素对猩红热发病的影响,为制定有针对性的防控措施提供科学依据。方法收集北京市西城区2010—2019年猩红热逐日发病数据和同期气象数据,以年份、月份、星期几作为时间分层变量,在控制长期趋势、季节性及其他... 目的探讨北京市西城区气象因素对猩红热发病的影响,为制定有针对性的防控措施提供科学依据。方法收集北京市西城区2010—2019年猩红热逐日发病数据和同期气象数据,以年份、月份、星期几作为时间分层变量,在控制长期趋势、季节性及其他混杂因素基础上,采用时间分层病例交叉设计的条件logistic回归模型分析西城区不同气象因素对猩红热病例数的影响。结果2010—2019年,西城区累计报告猩红热病例3195例,年均发病率为24.17/10万,整体呈波动下降趋势,期间出现3次发病高峰,以2011年发病率最高,无重症及死亡病例。猩红热发病呈现明显的季节性双峰分布的特征,主要集中在每年4~6月、11月至次年1月。条件logistic回归结果显示:平均相对湿度、平均温度与猩红热病例之间呈正相关(β=0.0203,β=0.0613,P<0.001),平均水汽压与猩红热病例之间呈负相关(β=-0.1468,P<0.001)。平均相对湿度和平均温度的增加是猩红热发病的危险因素(OR=1.0205,95%CI:1.0150~1.0261;OR=1.0632,95%CI:1.0379~1.0891),平均相对湿度每增加1.00%,猩红热病例数将增加2.05%(1.50%~2.61%);平均气温每增加1℃,猩红热病例数将增加6.32%(3.79%~8.91%)。平均水汽压的增加对猩红热发病具有一定程度的保护作用(OR=0.8635,95%CI:0.8392~0.8885),平均水汽压每增加1hpa,猩红热病例数将减少13.65%(11.15%~16.08%)。结论平均相对湿度、平均气温和平均水汽压是影响北京市西城区猩红热发病的主要气象因素,可将其作为猩红热防控和监测预警的指标。 展开更多
关键词 猩红热 气象因素 时间分层病例交叉研究 条件LOGISTIC回归
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牙髓干细胞及衍生产物在牙髓再生中的应用与进展
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作者 徐海超 罗丽花 潘乙怀 《中国组织工程研究》 北大核心 2026年第1期153-162,共10页
背景:牙髓干细胞是一类源自牙髓组织的牙源性间充质干细胞,具有良好的自我更新和多向分化潜力。近年来,牙髓干细胞及其衍生产物包括细胞外囊泡、条件培养液以及脱细胞基质等,在牙髓组织损伤修复再生中的应用研究取得了显著进展,显示出... 背景:牙髓干细胞是一类源自牙髓组织的牙源性间充质干细胞,具有良好的自我更新和多向分化潜力。近年来,牙髓干细胞及其衍生产物包括细胞外囊泡、条件培养液以及脱细胞基质等,在牙髓组织损伤修复再生中的应用研究取得了显著进展,显示出广阔的临床应用前景。目的:系统综述牙髓干细胞及其衍生产物在牙髓组织工程中的研究成果和应用进展。方法:检索PubMed数据库、中国生物医学文献数据库、中国知网,以“牙髓干细胞,细胞外囊泡,外泌体,凋亡小体,条件培养液,脱细胞基质,再生”为中文检索词,以“dental pulp stem cells,extracellular vesicles,exosomes,apoptotic bodies,conditioned medium,decellularized matrix,regeneration”为英文检索词进行检索,检索时限为2005年1月至2023年6月。根据文题和摘要对初检文献进行筛选,排除重复文献和与主题不相关的文献,最终纳入103篇与牙髓再生高度相关的文献进行综述分析。结果与结论:牙髓干细胞及其衍生产物富含多种生物活性因子,能够有效促进成牙本质、成血管和成神经分化,在牙髓-牙本质复合体的形成过程中展现出巨大的应用潜力。然而,牙髓干细胞及其衍生产物在临床应用转化中仍面临挑战,未来的研究应着重于优化制备流程、明确作用机制和完善安全性评价,为推动临床牙髓损伤修复提供新的治疗策略。 展开更多
关键词 牙髓干细胞 细胞外囊泡 条件培养液 脱细胞基质 牙髓再生 组织工程 工程化干细胞
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唐山市空气污染与气象条件耦合性研究
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作者 王猛 代立芹 +2 位作者 许莹 王艺泽 刘丹 《环境科学与管理》 2026年第1期126-131,共6页
唐山市作为中国重要的工业城市,空气污染问题备受关注。文章基于2015年至2023年的空气污染物(PM_(2.5)、PM_(10)、SO_(2)、NO_(2)、O_(3)等)和气象条件(温度、湿度、风速、气压等)数据,采用相关性分析、多元回归模型、扩散条件公式计算... 唐山市作为中国重要的工业城市,空气污染问题备受关注。文章基于2015年至2023年的空气污染物(PM_(2.5)、PM_(10)、SO_(2)、NO_(2)、O_(3)等)和气象条件(温度、湿度、风速、气压等)数据,采用相关性分析、多元回归模型、扩散条件公式计算、温湿度联合影响分析和典型案例研究等方法,系统探讨了气象条件与污染物浓度的耦合关系。研究表明,静稳天气、高湿度条件和低风速是污染物浓度累积的主要气象驱动因素,而温湿度对PM_(2.5)的联合影响显著且具有非线性特征。研究结合数据分析与模型构建,为优化空气质量管理提供理论支撑,具有重要参考价值。 展开更多
关键词 空气污染 气象条件 静稳天气 温湿度联合作用 多元回归
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TONE MODELING BASED ON HIDDEN CONDITIONAL RANDOM FIELDS AND DISCRIMINATIVE MODEL WEIGHT TRAINING 被引量:1
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作者 黄浩 朱杰 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2008年第1期43-50,共8页
The use of hidden conditional random fields (HCRFs) for tone modeling is explored. The tone recognition performance is improved using HCRFs by taking advantage of intra-syllable dynamic, inter-syllable dynamic and d... The use of hidden conditional random fields (HCRFs) for tone modeling is explored. The tone recognition performance is improved using HCRFs by taking advantage of intra-syllable dynamic, inter-syllable dynamic and duration features. When the tone model is integrated into continuous speech recognition, the discriminative model weight training (DMWT) is proposed. Acoustic and tone scores are scaled by model weights discriminatively trained by the minimum phone error (MPE) criterion. Two schemes of weight training are evaluated and a smoothing technique is used to make training robust to overtraining problem. Experiments show that the accuracies of tone recognition and large vocabulary continuous speech recognition (LVCSR) can be improved by the HCRFs based tone model. Compared with the global weight scheme, continuous speech recognition can be improved by the discriminative trained weight combinations. 展开更多
关键词 speech recognition MODELS hidden conditional random fields minimum phone error
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