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Impact of message fatigue and individual behavioral responses on epidemiological spread in temporal simplicial networks 被引量:1
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作者 Xiao-Nan Fan Xuemei You 《Chinese Physics B》 2025年第3期32-43,共12页
Health information spreads rapidly,which can effectively control epidemics.However,the swift dissemination of information also has potential negative impacts,which increasingly attracts attention.Message fatigue refer... Health information spreads rapidly,which can effectively control epidemics.However,the swift dissemination of information also has potential negative impacts,which increasingly attracts attention.Message fatigue refers to the psychological response characterized by feelings of boredom and anxiety that occur after receiving an excessive amount of similar information.This phenomenon can alter individual behaviors related to epidemic prevention.Additionally,recent studies indicate that pairwise interactions alone are insufficient to describe complex social transmission processes,and higher-order structures representing group interactions are crucial.To address this,we develop a novel epidemic model that investigates the interactions between information,behavioral responses,and epidemics.Our model incorporates the impact of message fatigue on the entire transmission system.The information layer is modeled using a static simplicial network to capture group interactions,while the disease layer uses a time-varying network based on activity-driven model with attractiveness to represent the self-protection behaviors of susceptible individuals and self-isolation behaviors of infected individuals.We theoretically describe the co-evolution equations using the microscopic Markov chain approach(MMCA)and get the epidemic threshold.Experimental results show that while the negative impact of message fatigue on epidemic transmission is limited,it significantly weakens the group interactions depicted by higher-order structures.Individual behavioral responses strongly inhibit the epidemic.Our simulations using the Monte Carlo(MC)method demonstrate that greater intensity in these responses leads to clustering of susceptible individuals in the disease layer.Finally,we apply the proposed model to real networks to verify its reliability.In summary,our research results enhance the understanding of the information-epidemic coupling dynamics,and we expect to provide valuable guidance for managing future emerging epidemics. 展开更多
关键词 Monte Carlo simulation microscopic Markov chain approach message fatigue information-epidemic coupled spreading simplicial complex
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Endoscopic and laparoscopic treatment of ileocecal laterally spreading tumor with concomitant appendiceal adenoma:A case report and review of literature
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作者 Ying-Hui Huang Li Ma +6 位作者 Bin Cao Yue-Juan Zhang Qun Gao Zhen-Ming Zhu Xiao-Lu Qiao Lei Wang Bao-Guo He 《World Journal of Gastrointestinal Surgery》 2025年第9期448-454,共7页
BACKGROUND Ileocecal laterally spreading tumors(LSTs)complicated by appendiceal tubular adenoma are rare and challenging to diagnose because of the absence of typical symptoms and specific diagnostic signs.Traditional... BACKGROUND Ileocecal laterally spreading tumors(LSTs)complicated by appendiceal tubular adenoma are rare and challenging to diagnose because of the absence of typical symptoms and specific diagnostic signs.Traditionally,the primary treatment has been laparoscopic appendectomy(LA).CASE SUMMARY A 63-year-old female presented with changes in bowel habits.Colonoscopy revealed an ileocecal LST.The patient underwent endoscopic submucosal dissection.Postoperative follow-up colonoscopy revealed mucosal elevation at the appendiceal orifice,with pathology confirming tubular adenoma.Abdominal computed tomography indicated a suspicious appendiceal tumor,leading to LA with partial cecectomy.The postoperative recovery was uneventful.At the 1-year follow-up,colonoscopy revealed no evidence of tumor recurrence.CONCLUSION Ileocecal LSTs with appendiceal tubular adenomas are traditionally treated with LA.endoscopic submucosal dissection can also yield favorable outcomes. 展开更多
关键词 Appendiceal tubular adenoma Ileocecal laterally spreading tumor Appendiceal laterally spreading tumor Endoscopic submucosal dissection Laparoscopic appendectomy Case report
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Modeling the spread risk of dengue vector Aedes albopictus caused by environmental factors in Shanghai China
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作者 Jiamin Wang Yanfeng Gong +7 位作者 Junhui Huang Ning Xu Yu Zhou Liyun Zhu Liang Shi Yue Chen Qingwu Jiang Yibiao Zhou 《Asian Pacific Journal of Tropical Medicine》 2025年第6期261-268,共8页
Objective:To predict the distribution of dengue vector Aedes(Ae.)albopictus and identify high-risk areas for dengue fever transmission.Methods:Data on Ae.albopictus occurrences were collected from electronic databases... Objective:To predict the distribution of dengue vector Aedes(Ae.)albopictus and identify high-risk areas for dengue fever transmission.Methods:Data on Ae.albopictus occurrences were collected from electronic databases.Ensemble models were developed to assess the impacts of climate,vegetation,and human activity on Ae.albopictus.The optimal ensemble model was then used to identify the distribution of suitable areas for Ae.albopictus.Results:After removing duplicate sites and retaining only one location per 100 m×100 m grid,189 Ae.albopictus breeding sites were identified.The optimal ensemble model revealed that Ae.albopictus exhibited higher breeding suitability in Shanghai under specific conditions:a normalized difference vegetation index of 0.1 to 0.6,maximum precipitation in the warmest month ranging from 400 mm to 470 mm,maximum temperature in the warmest month between 30.0℃and 31.0℃,and proximity to waterways within 0.5 km.The most suitable habitats for Ae.albopictus were primarily concentrated in Shanghai’s central urban areas and scattered across the inner suburban districts.Conclusions:The high-risk areas of Ae.albopictus are widely distributed throughout the central urban area and scattered across the inner suburban district of Shanghai,creating conditions conducive to the outbreak of dengue fever.It is essential to enhance targeted control measures for Ae.albopictus in the identified risk areas. 展开更多
关键词 DENGUE spread risk Prediction METROPOLITAN Aedes albopictus
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Influence of negative information dissemination and vaccination behavioral decision-making on epidemic spreading in a three-layer network
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作者 Liang'an Huo Leyao Yin 《Chinese Physics B》 2025年第6期667-681,共15页
Information plays a crucial role in guiding behavioral decisions during public health emergencies. Individuals communicate to acquire relevant knowledge about an epidemic, which influences their decisions to adopt pro... Information plays a crucial role in guiding behavioral decisions during public health emergencies. Individuals communicate to acquire relevant knowledge about an epidemic, which influences their decisions to adopt protective measures.However, whether to disseminate specific information is also a behavioral decision. In light of this understanding, we develop a coupled information–vaccination–epidemic model to depict these co-evolutionary dynamics in a three-layer network. Negative information dissemination and vaccination are treated as separate decision-making processes. We then examine the combined effects of herd and risk motives on information dissemination and vaccination decisions through the lens of game theory. The microscopic Markov chain approach(MMCA) is used to describe the dynamic process and to derive the epidemic threshold. Simulation results indicate that increasing the cost of negative information dissemination and providing timely clarification can effectively control the epidemic. Furthermore, a phenomenon of diminishing marginal utility is observed as the cost of dissemination increases, suggesting that authorities do not need to overinvest in suppressing negative information. Conversely, reducing the cost of vaccination and increasing vaccine efficacy emerge as more effective strategies for outbreak control. In addition, we find that the scale of the epidemic is greater when the herd motive dominates behavioral decision-making. In conclusion, this study provides a new perspective for understanding the complexity of epidemic spreading by starting with the construction of different behavioral decisions. 展开更多
关键词 negative information VACCINATION epidemic spreading behavioral decision-making three-layer network
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SPREADING SPEED FOR A TIME-SPACE PERIODIC EPIDEMIC MODEL IN DISCRETE MEDIA
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作者 Haiqin ZHAO 《Acta Mathematica Scientia》 2025年第3期1005-1018,共14页
This paper is devoted to investigating the spreading speed of a time-space periodic epidemic model with vital dynamics and standard incidence in discrete media. We establish the existence of the leftward and rightward... This paper is devoted to investigating the spreading speed of a time-space periodic epidemic model with vital dynamics and standard incidence in discrete media. We establish the existence of the leftward and rightward spreading speeds for the infective individuals, which can be used to estimate how fast the disease spreads. To overcome the difficulty arising from the lack of comparison principle for such time-space periodic nonmonotone systems, our proof is mainly based on constructing a series of scalar time-space periodic equations, establishing the spreading speeds for such auxiliary equations and using comparison methods. It may be the first work to study the spreading speed for time-space periodic non-monotone systems. 展开更多
关键词 spreading speed epidemic models time-space periodic habitats
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A stacking-based model for the spread of Botryosphaeria laricina
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作者 Hongwei Zhou Shibo Zhang +3 位作者 Meng Xie Xiaodong Li Yifan Chen Wenhao Dai 《Journal of Forestry Research》 2025年第1期427-443,共17页
Botryosphaeria laricina(larch shoot blight)was first identified in 1973 in Jilin Province,China.The disease spread rapidly and caused considerable damage because its pathogenesis was unknown at the time and there were... Botryosphaeria laricina(larch shoot blight)was first identified in 1973 in Jilin Province,China.The disease spread rapidly and caused considerable damage because its pathogenesis was unknown at the time and there were no effective controls or quarantine methods.At present,it shows a spreading trend,but most research can only conduct physiological analyses within a relatively short period,combining individual influencing factors.Nevertheless,methods such as neural network models,ensemble learning algorithms,and Markov models are used in pest and disease prediction and forecasting.However,there may be fitting issues or inherent limitations associated with these methods.This study obtained B.laricina data at the county level from 2003 to 2021.The dataset was augmented using the SMOTE algorithm,and then algorithms such as XGBoost were used to select the significant features from a combined set of 12 features.A new stacking fusion model has been proposed to predict the status of B.laricina.The model is based on random forest,gradient boosted decision tree,CatBoost and logistic regression algorithms.The accuracy,recall,specificity,precision,F_(1) value and AUC of the model reached 90.9%,91.6%,90.4%,88.8%,90.2%and 96.2%.The results provide evidence of the strong performance and stability of the model.B.laricina is mainly found in the northeast and this study indicates that it is spreading northwest.Reasonable means should be used promptly to prevent further damage and spread. 展开更多
关键词 Botryosphaeria laricina Data augmentation Feature selection STACKING Status of spread
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Explosive information spreading in higher-order networks:Effect of social reinforcement
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作者 Yu Zhou Yingpeng Liu +4 位作者 Liang Yuan Youhao Zhuo Kesheng Xu Jiao Wu Muhua Zheng 《Chinese Physics B》 2025年第3期196-202,共7页
Information spreading has been investigated for many years,but the mechanism of why the information explosively catches on overnight is still under debate.This explosive spreading phenomenon was usually considered dri... Information spreading has been investigated for many years,but the mechanism of why the information explosively catches on overnight is still under debate.This explosive spreading phenomenon was usually considered driven separately by social reinforcement or higher-order interactions.However,due to the limitations of empirical data and theoretical analysis,how the higher-order network structure affects the explosive information spreading under the role of social reinforcement has not been fully explored.In this work,we propose an information-spreading model by considering the social reinforcement in real and synthetic higher-order networks,describable as hypergraphs.Depending on the average group size(hyperedge cardinality)and node membership(hyperdegree),we observe two different spreading behaviors:(i)The spreading progress is not sensitive to social reinforcement,resulting in the information localized in a small part of nodes;(ii)a strong social reinforcement will promote the large-scale spread of information and induce an explosive transition.Moreover,a large average group size and membership would be beneficial to the appearance of the explosive transition.Further,we display that the heterogeneity of the node membership and group size distributions benefit the information spreading.Finally,we extend the group-based approximate master equations to verify the simulation results.Our findings may help us to comprehend the rapidly information-spreading phenomenon in modern society. 展开更多
关键词 explosive information spreading social reinforcement higher-order interactions complex network
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Trending and emerging prospects of physics-based and ML-based wildfire spread models:a comprehensive review
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作者 Harikesh Singh Li‑Minn Ang +4 位作者 Tom Lewis Dipak Paudyal Mauricio Acuna Prashant Kumar Srivastava Sanjeev Kumar Srivastava 《Journal of Forestry Research》 2025年第1期27-59,共33页
The significant threat of wildfires to forest ecology and biodiversity,particularly in tropical and subtropical regions,underscores the necessity for advanced predictive models amidst shifting climate patterns.There i... The significant threat of wildfires to forest ecology and biodiversity,particularly in tropical and subtropical regions,underscores the necessity for advanced predictive models amidst shifting climate patterns.There is a need to evaluate and enhance wildfire prediction methods,focusing on their application during extended periods of intense heat and drought.This study reviews various wildfire modelling approaches,including traditional physical,semi-empirical,numerical,and emerging machine learning(ML)-based models.We critically assess these models’capabilities in predicting fire susceptibility and post-ignition spread,highlighting their strengths and limitations.Our findings indicate that while traditional models provide foundational insights,they often fall short in dynamically estimating parameters and predicting ignition events.Cellular automata models,despite their potential,face challenges in data integration and computational demands.Conversely,ML models demonstrate superior efficiency and accuracy by leveraging diverse datasets,though they encounter interpretability issues.This review recommends hybrid modelling approaches that integrate multiple methods to harness their combined strengths.By incorporating data assimilation techniques with dynamic forecasting models,the predictive capabilities of ML-based predictions can be significantly enhanced.This review underscores the necessity for continued refinement of these models to ensure their reliability in real-world applications,ultimately contributing to more effective wildfire mitigation and management strategies.Future research should focus on improving hybrid models and exploring new data integration methods to advance predictive capabilities. 展开更多
关键词 Wildfire spread Fire prediction models Cellular automata model WRF-Fire/SFire FIRETEC CAWFE WFDS
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Activation of peroxymonosulfate by sustainable biomass-based carbon nanotubes for controlling the spread of plant viruses in water environments
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作者 Jian Tang Yujie Wang +2 位作者 JunMa Yujie Chen Ming Chen 《Journal of Environmental Sciences》 2025年第3期99-112,共14页
With the increasing demand for water in hydroponic systems and agricultural irrigation,viral diseases have seriously affected the yield and quality of crops.By removing plant viruses in water environments,virus transm... With the increasing demand for water in hydroponic systems and agricultural irrigation,viral diseases have seriously affected the yield and quality of crops.By removing plant viruses in water environments,virus transmission can be prevented and agricultural production and ecosystems can be protected.But so far,there have been few reports on the removal of plant viruses in water environments.Herein,in this study,easily recyclable biomass-based carbon nanotubes catalysts were synthesized with varying metal activities to activate peroxymonosulfate(PMS).Among them,the magnetic 0.125Fe@NCNTs-1/PMS system showed the best overall removal performance against pepper mild mottle virus,with a 5.9 log_(10)removal within 1 min.Notably,the key reactive species in the 0.125Fe@NCNTs-1/PMS system is^(1)O_(2),which can maintain good removal effect in real water matrices(river water and tap water).Through RNA fragment analyses and label free analysis,it was found that this system could effectively cleave virus particles,destroy viral proteins and expose their genome.The capsid protein of pepper mild mottle virus was effectively decomposed where serine may be the main attacking sites by^(1)O_(2).Long viral RNA fragments(3349 and 1642 nt)were cut into smaller fragments(∼160 nt)and caused their degradation.In summary,this study contributes to controlling the spread of plant viruses in real water environment,which will potentially help protect agricultural production and food safety,and improve the health and sustainability of ecosystems. 展开更多
关键词 Pepper mild mottle virus Removal Plant virus spread Biomass-based carbon nanotubes Water environments
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Endoscopic resection of colorectal laterally spreading tumors:Clinicopathologic characteristics and risk factors for treatment outcomes
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作者 Li-Hua Guo Ke-Feng Hu +3 位作者 Min Miao Yong Ding Xin-Jun Zhang Guo-Liang Ye 《World Journal of Gastrointestinal Endoscopy》 2025年第6期85-98,共14页
BACKGROUND Colorectal laterally spreading tumors(LSTs)are best treated with endoscopic submucosal dissection or endoscopic mucosal resection.AIM To analyze the clinicopathological and endoscopic profiles of colorectal... BACKGROUND Colorectal laterally spreading tumors(LSTs)are best treated with endoscopic submucosal dissection or endoscopic mucosal resection.AIM To analyze the clinicopathological and endoscopic profiles of colorectal LSTs,determine predictive factors for high-grade dysplasia(HGD)/carcinoma(CA),submucosal invasion,and complications.METHODS We retrospectively assessed the endoscopic and histological characteristics of 375 colorectal LSTs at our hospital between January 2016 and December 2023.We performed univariate and multivariate analysis to identify risk factors associated with HGD/CA,submucosal invasion and complications.RESULTS The numbers of granular(LST-G)and non-granular LST(LST-NG)were 260 and 115,respectively.The rates of low-grade dysplasia and HGD/CA were 60.3%and 39.7%,respectively.Multivariate analysis indicated that a tumor size≥30 mm[odds ratio(OR)=1.934,P=0.032],LST granular nodular mixed type(OR=2.100,P=0.005),and LST non-granular pseudo depressed type(NG-PD)(OR=3.016,P=0.015)were independent risk factors significantly associated with higher odds of HGD/CA.NG-PD(OR=6.506,P=0.001),tumor size(20-29 mm)(OR=2.631,P=0.036)and tumor size≥30 mm(OR=3.449,P=0.016)were associated with increased odds of submucosal invasion.Tumor size≥30 mm(OR=4.888,P=0.003)was a particularly important predictor of complications.A nomogram model demonstrated a satisfactory fit,with an area under the receiver operating characteristic curve of 0.716(95%confidence interval:0.653-0.780),indicating strong predictive performance.CONCLUSION The novel nomogram incorporating tumor size,location,and morphology predicted HGD/CA during endoscopic resection for LSTs.NG-PD lesions larger than 20 mm were more likely to invade the submucosa.Tumor size≥30 mm was an important predictor of complications. 展开更多
关键词 Colorectal neoplasms Laterally spreading tumor Endoscopic morphology Endoscopic submucosal dissection Endoscopic mucosal resection Submucosal invasion
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变温摊青处理对龙井茶风味品质的影响
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作者 崔宏春 余继忠 +3 位作者 师大亮 张建勇 汪峰 张再清 《浙江农业科学》 2026年第1期148-155,共8页
摊青是龙井茶加工的第一道关键工序,是龙井茶风味品质形成的基石。本文采用“传统室温”摊青工艺(CK)、“室温+冷藏+室温”变温摊青工艺(V1)、“室温+冷藏+冷冻+室温”变温摊青工艺(V2)、“室温+冷冻+室温”变温摊青工艺(V3)等4种摊青... 摊青是龙井茶加工的第一道关键工序,是龙井茶风味品质形成的基石。本文采用“传统室温”摊青工艺(CK)、“室温+冷藏+室温”变温摊青工艺(V1)、“室温+冷藏+冷冻+室温”变温摊青工艺(V2)、“室温+冷冻+室温”变温摊青工艺(V3)等4种摊青方式加工龙井茶,通过感官品质和风味化学物质含量的比较分析,以及感官评价得分与风味化学物质含量的相关性,探究变温摊青处理对龙井茶风味品质的影响。结果表明,变温摊青工艺V1、V2、V3加工的龙井茶感官评分高于CK,外形扁平度和匀度、汤色明亮度、香气持久度、滋味醇爽度等品质更优,变温摊青工艺V3加工的龙井茶感官品质最好。变温摊青工艺V1、V2、V3的茶多酚含量、水浸出物含量、儿茶素含量显著(p<0.05)高于CK,变温摊青工艺V3的上述指标显著高于变温摊青工艺V1、V2,与感官评价变化趋势一致。变温摊青工艺V2、V3的游离氨基酸含量显著高于CK和V1。变温摊青工艺V1、V2、V3的咖啡碱含量显著高于CK,变温摊青工艺V1、V2、V3的咖啡碱含量之间无显著差异。与CK相比,变温摊青工艺V1、V2、V3的表没食子儿茶素没食子酸酯(EGCG)、表没食子儿茶素(EGC)、没食子儿茶素没食子酸酯(GCG)等组分含量较高,表儿茶素没食子酸酯(ECG)、儿茶素没食子酸酯(CG)等组分含量较低。与CK和V1相比,变温摊青工艺V2、V3的表儿茶素(EC)、儿茶素(C)、没食子儿茶素(GC)等组分含量较高。GC、EGCG、C、EC、游离氨基酸、茶多酚、水浸出物是龙井茶主要的风味品质贡献物质。冷冻对于摊青后龙井茶风味品质的影响大于冷藏。变温摊青工艺,显著改善了龙井茶风味品质,可为龙井茶品质形成和调控研究提供技术支撑和理论依据。 展开更多
关键词 龙井茶 摊青 加工工艺 风味 品质 化学成分
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社会信用体系建设与债券信用利差——基于创建社会信用体系建设示范城市政策的准自然实验
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作者 张鹏 胡蝶 《现代金融研究》 北大核心 2026年第2期45-57,共13页
本文以2012-2019年中国A股上市公司在银行间与交易所市场发行的一般企业债、公司债和中期票据为样本,基于交错双重差分模型,评估创建社会信用体系建设示范城市的政策效应。结果表明:(1)该政策显著降低了政策实施地区的债券信用利差;(2)... 本文以2012-2019年中国A股上市公司在银行间与交易所市场发行的一般企业债、公司债和中期票据为样本,基于交错双重差分模型,评估创建社会信用体系建设示范城市的政策效应。结果表明:(1)该政策显著降低了政策实施地区的债券信用利差;(2)该效应主要通过提升信息透明度、改善融资能力和降低违约风险实现;(3)该效应在治理水平较低的企业、民营企业、剩余期限较长的债券及银行竞争激烈的地区中更显著;(4)该政策降低了试点地区债券一级市场发行利差并扩大了债券发行规模。 展开更多
关键词 社会信用体系建设 债券信用利差 风险定价 准自然实验
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质子超高剂量率效应在展宽布拉格峰处的验证研究
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作者 汪越 王巧娟 +3 位作者 刘建成 李灵 黄志豪 隋丽 《原子能科学技术》 北大核心 2026年第2期425-434,共10页
超高剂量率(FLASH)的辐照在临床实践上被认为具备正常组织保护效应,为更好地结合质子布拉格峰展宽与超高剂量率辐照两种优势技术,研究质子FLASH效应在展宽布拉格峰处是否有效,本研究利用中国原子能科学研究院的100 MeV质子对人正常肝细... 超高剂量率(FLASH)的辐照在临床实践上被认为具备正常组织保护效应,为更好地结合质子布拉格峰展宽与超高剂量率辐照两种优势技术,研究质子FLASH效应在展宽布拉格峰处是否有效,本研究利用中国原子能科学研究院的100 MeV质子对人正常肝细胞WRL68与人肝癌细胞Hep G2进行不同剂量率下的布拉格峰展宽辐照,并在不同的时间点后分别以CCK8法检测细胞增殖,以流式细胞术检测细胞周期阻滞与凋亡率,并用荧光法检测细胞中的活性氧(ROS)含量。结果表明,在展宽布拉格峰处同等辐照剂量下,质子FLASH照射大幅提高了正常肝细胞的增殖活力,降低了细胞凋亡率;对于肝癌细胞,质子FLASH照射降低了细胞增殖活力,细胞凋亡率显著升高;在周期阻滞模式方面,常规剂量率辐照更易引起严重的G2/M期阻滞,而FLASH辐照在早期表现为S期阻滞,其后随时间向G2/M期阻滞转移,肝癌细胞相较于正常细胞转移更迟;在FLASH照射下,两细胞中的ROS含量均表现为随时间振荡的变化趋势,而常规剂量率下则呈现随时间下降的趋势。以上结果表明,FLASH的正常组织保护效应在质子展宽布拉格峰区依然有效,同时维持了癌细胞杀伤效能,其作用机制可能与ROS含量的振荡变化相关,相关的信号通路可能包括p53等。研究在细胞层次证实了质子FLASH技术在展宽布拉格峰辐照模式下仍极具临床应用潜力。 展开更多
关键词 质子辐射 展宽布拉格峰 超高剂量率 细胞周期 活性氧含量
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南海中央海盆后扩张期岩浆活动
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作者 马浩明 邱燕 黄文凯 《海洋地质前沿》 北大核心 2026年第2期14-27,共14页
南海中央海盆海底扩张活动结束之后,出现了频繁的岩浆活动。由于海盆被海水覆盖,针对活跃的岩浆活动开展实测调查非常困难。本文利用二维地震剖面资料,结合拖网样品资料及有关钻探资料的研究成果,在建立岩浆活动与沉积作用关系模型的基... 南海中央海盆海底扩张活动结束之后,出现了频繁的岩浆活动。由于海盆被海水覆盖,针对活跃的岩浆活动开展实测调查非常困难。本文利用二维地震剖面资料,结合拖网样品资料及有关钻探资料的研究成果,在建立岩浆活动与沉积作用关系模型的基础上,通过解释地震剖面反射特征和地震相特征,较全面地分析了南海中央海盆扩张期后岩浆活动的特征与期次。结果表明,南海中央海盆的岩浆活动具有脉动期,形成大量的海底山和岩浆底辟,即以多期次间隙性喷发和浅层侵入为特征。南海中央海盆后扩张期的岩浆活动主要有4个期次,其中11.6、7.5、5.3 Ma 3个期次的分析结果与岩石样品的测年结果吻合,而且进一步确定1.6 Ma左右的岩浆活动时间较长,一直延续至近代,分布范围广;2.6~1.6 Ma期间曾被认为是南海中央海盆岩浆活动静默期,本研究首次发现岩浆活动的踪迹;这一时期既有一次性活动形成的岩浆底辟和海底火山,也有通过多次火山活动而形成的规模较大的岩浆底辟和海底火山。 展开更多
关键词 岩浆活动 后扩张期 活动期次 海底山和岩浆底辟 中央海盆 南海
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基于多功能表面的液滴撞击研究进展
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作者 刘瑞 陈璞 +2 位作者 牛喻樱 张卫 赵玉刚 《空气动力学学报》 北大核心 2026年第2期1-21,共21页
液滴撞击现象广泛存在,对其开展研究对防冰除冰、农药喷洒、喷墨打印等领域意义重大。随着高速摄像技术和表面制备技术的进步,各类多功能表面不断被开发利用,推动了对液滴撞击动力学特征与能量变化的深入研究。本文围绕液滴撞击过程中... 液滴撞击现象广泛存在,对其开展研究对防冰除冰、农药喷洒、喷墨打印等领域意义重大。随着高速摄像技术和表面制备技术的进步,各类多功能表面不断被开发利用,推动了对液滴撞击动力学特征与能量变化的深入研究。本文围绕液滴撞击过程中的基本参数展开,通过介绍最大铺展因子、接触时间及相关无因次数,深入探讨了液滴在单功能表面和多功能表面上的撞击现象及动力学特征,进一步说明因多功能表面这类特殊表面的各向异性特征,使得液滴撞击时会呈现出定向位移、自裂、自旋转等特殊运动现象。从表面特性出发,介绍了化学改性多功能表面、微观物理结构调控多功能表面、宏观特殊形状多功能表面及外场耦合多功能表面,详细描述了液滴撞击这些表面时的特异现象及其动力学行为,并提供了理论模型和应用实例,旨在通过深入探索液滴撞击的动力学特征,为多功能表面的优化设计及多领域应用提供理论支持与技术指导。 展开更多
关键词 液滴撞击 多功能表面 最大铺展因子 接触时间 动力学行为
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基于元胞自动机模型的松材线虫病小班尺度预测
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作者 周宏威 李永正 +5 位作者 郭文辉 陈怡帆 胡浩昌 张思岩 崔迪 陈雨茉 《林业科学》 北大核心 2026年第1期133-143,共11页
【目的】为探究影响松材线虫病传播扩散的主要影响因素,结合自然气候、人类活动以及地理空间特征多源数据,围绕松材线虫病“传入-定殖-扩散”的生态入侵过程,构建适用于更小空间尺度数据的传播预测模型,实现对松材线虫病高风险发生地区... 【目的】为探究影响松材线虫病传播扩散的主要影响因素,结合自然气候、人类活动以及地理空间特征多源数据,围绕松材线虫病“传入-定殖-扩散”的生态入侵过程,构建适用于更小空间尺度数据的传播预测模型,实现对松材线虫病高风险发生地区的精准预测和早期预警。【方法】基于国家林业和草原局公布的江苏省松材线虫病小班本底发生数据,结合松材线虫病的生态特性和地理空间分布规律,选取包含自然气候、人类活动因素以及空间特征等25项影响因子数据,采用主成分分析方法进行数据预处理,通过Spearman相关性分析方法和Apriori数据挖掘算法,探究各影响因子与松材线虫病发生之间的相互作用关系。结合贝叶斯估计方法对影响因子数据进行特征增强,建立灰狼优化算法-元胞自动机模型模拟松材线虫病的传播扩散过程,同时与其他5种主流机器学习模型预测结果进行横向对比验证,通过计算其精确率、召回率和AUC等评价指标对模型性能进行验证。【结果】构建的灰狼优化算法-元胞自动机模型在松材线虫病新发小班预测中表现出优异的性能,模型召回率达到78.5%,显著优于其他5种主流机器学习模型;同时,其AUC值达到89.0%,表明模型在识别新发疫情点位的同时,兼顾较高的整体预测准确性与判别能力。本研究进一步证实地理空间特征在松材线虫病传播预测中的重要性,并验证元胞自动机模型在处理复杂时空数据和更精细尺度空间数据预测方面的高度适用性。【结论】木材运输是驱动松材线虫病传播扩散的关键因素,而温度与降水的差异也在显著程度上影响其发生风险。作为一种融合空间异质性与时间动态特征的建模方法,元胞自动机模型在处理复杂生态数据与入侵物种风险评估方面展现出较高的适用性与灵活性,可为松材线虫病的精准防控与高效管理提供有力的技术支撑。 展开更多
关键词 松材线虫病 传播预测模型 大数据 数据挖掘 元胞自动机
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内镜黏膜下剥离术在≥10 cm直肠侧向发育型肿瘤治疗中的应用效果——3例病例报告
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作者 徐艳玲 周鸿捷 饶敏 《广西医学》 2026年第2期192-196,共5页
目的探讨内镜黏膜下剥离术(ESD)治疗≥10 cm直肠侧向发育型肿瘤(LST)的临床效果及安全性。方法回顾性分析3例≥10 cm直肠LST患者的临床表现及ESD治疗过程。结果3例患者的直肠LST均通过ESD达到整块切除效果,术中及术后无明显出血及穿孔发... 目的探讨内镜黏膜下剥离术(ESD)治疗≥10 cm直肠侧向发育型肿瘤(LST)的临床效果及安全性。方法回顾性分析3例≥10 cm直肠LST患者的临床表现及ESD治疗过程。结果3例患者的直肠LST均通过ESD达到整块切除效果,术中及术后无明显出血及穿孔发生,术后病理提示切缘为阴性。1例患者术后1个月出现直肠狭窄,经过球囊扩张治疗后恢复良好。结论ESD治疗≥10 cm的直肠LST可以达到完全切除效果,安全性良好。 展开更多
关键词 直肠肿瘤 侧向发育型肿瘤 内镜黏膜下剥离术 病例报告
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面肌痉挛患者显微血管减压术中侧方扩散反应与术后近远期疗效的关系
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作者 王凯 尚明 《中国实用神经疾病杂志》 2026年第1期14-19,共6页
目的探究面肌痉挛患者显微血管减压术(MVD)中侧方扩散反应(LSR)与术后近远期疗效的关系。方法回顾性分析2020-02—2024-02徐州市中心医院收治的110例面肌痉挛患者的临床资料,将颧支和下颌缘支LSR均消失或两支中任一支消失纳入LSR消失组(... 目的探究面肌痉挛患者显微血管减压术(MVD)中侧方扩散反应(LSR)与术后近远期疗效的关系。方法回顾性分析2020-02—2024-02徐州市中心医院收治的110例面肌痉挛患者的临床资料,将颧支和下颌缘支LSR均消失或两支中任一支消失纳入LSR消失组(n=97),颧支和下颌缘支LSR均未消失纳入LSR未消失组(n=13)。分析LSR消失组颧支与下颌缘支LSR消失情况,分析LSR是否消失、消失时机与术后近期(1周内)、远期(1周~1 a)疗效的关系,绘制受试者工作特征(ROC)曲线评价LSR是否消失、消失时机对术后面肌痉挛近期、远期疗效的预测效能。结果术后近期、远期疗效比较,LSR消失组优于LSR未消失组,差异均有统计学意义(P<0.05)。不同术中LSR消失时机患者术后面肌痉挛近期、远期疗效比较有统计学差异(P<0.05)。ROC曲线分析显示,LSR是否消失评估术后面肌痉挛近期、远期疗效的AUC分别为0.621、0.702,敏感度分别为90.82%、90.38%,特异度分别为33.33%、50.00%;LSR消失时机评估术后面肌痉挛近期、远期疗效的AUC分别为0.631、0.691,敏感度分别为63.73%、63.21%,特异度分别为62.50%、75.00%。结论面肌痉挛患者术中LSR是否消失及消失时机对MVD术后近远期疗效具有一定的预测价值,临床应结合患者的临床症状及其他辅助检查综合判断,以改善患者长期预后。 展开更多
关键词 面肌痉挛 显微血管减压术 侧方扩散反应 预后 预测效能
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权力寻租:粤海关陋规名目及其危害
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作者 王宏斌 《河北师范大学学报(哲学社会科学版)》 2026年第1期21-38,共18页
“陋规”,乃是明清时期一种缺乏明确规定的,却又是实际运行的,得到官场默认的、普遍存在的、收受费用之潜规则。粤海关作为清代对外贸易的窗口,是一个比较特殊的部门。粤海关陋规名目前后有25种之多,几乎遍及收税、查验的每一个环节。... “陋规”,乃是明清时期一种缺乏明确规定的,却又是实际运行的,得到官场默认的、普遍存在的、收受费用之潜规则。粤海关作为清代对外贸易的窗口,是一个比较特殊的部门。粤海关陋规名目前后有25种之多,几乎遍及收税、查验的每一个环节。追根溯源,陋规的孽生和传染,既是官吏薪水制度、政府财政制度存在较大漏洞导致的,更是人治社会和缺乏内外监督造成的。粤海关陋规既具有一定遗传性,又具有巨大社会危害性和传染性。1840年之前的中国毒品泛滥,既是英属印度政府千方百计扶持对华鸦片走私贸易的结果,又与粤海关陋规盛行存在一定的因果联系。 展开更多
关键词 粤海关 陋规名目 权力寻租 传染性 鸦片战争
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森林离散燃料火蔓延研究前沿与展望
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作者 谭芷然 雷佼 《工程热物理学报》 北大核心 2026年第1期301-316,共16页
森林可燃物是典型的离散细颗粒燃料,燃料间的空气间隙显著影响火蔓延行为。本文根据森林可燃物特征定义了离散燃料,回顾了前人的研究工作,重点关注燃料间距、燃料床宽度、燃料长度、体积密度、填充比、风速和坡度角等因素对离散燃料火... 森林可燃物是典型的离散细颗粒燃料,燃料间的空气间隙显著影响火蔓延行为。本文根据森林可燃物特征定义了离散燃料,回顾了前人的研究工作,重点关注燃料间距、燃料床宽度、燃料长度、体积密度、填充比、风速和坡度角等因素对离散燃料火蔓延行为的影响规律,总结了已有的离散燃料火蔓延临界判据,以及水平无风、倾斜无风和水平有风条件下离散燃料火蔓延的传热机制和预测模型,并提出未来可以进一步研究的方向。 展开更多
关键词 森林火灾 离散燃料 火蔓延 传热机制 预测模型
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