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Spatial-Temporal Dynamics of Dongzhaigang Mangrove Forests on Hainan Island,China:Evidence from Landsat Observations(1988–2019)
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作者 Bing Tu Kang Peng +4 位作者 Xianjun Xie Lu Yan Yamin Deng Yiqun Gan Qinghua Li 《Journal of Earth Science》 2026年第1期289-302,共14页
The goal of this study was to determine the spatiotemporal characteristics of mangrove distribution and fragmentation patterns from 1988 through 2019 in Dongzhaigang.Land cover datasets were generated for Dongzhaigang... The goal of this study was to determine the spatiotemporal characteristics of mangrove distribution and fragmentation patterns from 1988 through 2019 in Dongzhaigang.Land cover datasets were generated for Dongzhaigang for multiple years via a decision tree method based on a classification and regression tree(CART)algorithm using Landsat time series images.Spatiotemporal transform and fragmentation patterns of mangrove distribution were separately assessed with a transfer matrix of land cover types and a landscape pattern index.The classification method combined with multi-band images showed good accuracy,with overall accuracy higher than 90%.Mangrove areas in 1988,1999,2009,and 2019 were 2050,1875,1818,and 1750 ha,respectively,with decreases mainly due to conversion to aquaculture ponds and farmland.A mangrove growth index(MGI)was proposed,reflecting the water-mangrove relationship,showing positive mangrove growth from 1988–2009 and negative growth from 2009–2019.Study results indicated anthropogenic factors play a leading role in the extent and scale of mangrove effects over the past 30 years.According to the analysis results,corresponding management and protection measures are proposed to provide reference for the sustainable development of Dongzhaigang Mangrove Wetland ecosystem. 展开更多
关键词 mangrove forests spatial-temporal data Hainan Island decision trees Landsat image
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A novel deviation measurement for scheduled intelligent transportation system via comparative spatial-temporal path networks
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作者 Daozhong Feng Jiajian Lai +1 位作者 Wenxuan Wei Bin Hao 《Digital Communications and Networks》 2026年第1期101-118,共18页
Transit managers can use Intelligent Transportation System technologies to access large amounts of data to monitor network status.However,the presentation of the data lacks structural information.Existing single-netwo... Transit managers can use Intelligent Transportation System technologies to access large amounts of data to monitor network status.However,the presentation of the data lacks structural information.Existing single-network description technologies are ineffective in representing the temporal and spatial characteristics simultaneously.Therefore,there is a need for complementary methods to address these deficiencies.To address these limitations,this paper proposes an approach that combines Network Snapshots and Temporal Paths for the scheduled system.A dual information network is constructed to assess the degree of operational deviation considering the planning tasks.To validate the effectiveness,discussions are conducted through a modified cosine similarity calculation on theoretical analysis,delay level description,and the ability to identify abnormal dates.Compared to some state-of-the-art methods,the proposed method achieves an average Spearman delay correlation of 0.847 and a relative distance of 3.477.Furthermore,case analyses are invested in regions of China's Mainland,Europe,and the United States,investigating both the overall and sub-regional network fluctuations.To represent the impact of network fluctuations in sub-regions,a response loss value was developed.The times that are prone to fluctuations are also discussed through the classification of time series data.The research can offer a novel approach to system monitoring,providing a research direction that utilizes individual data combined to represent macroscopic states.Our code will be released at https://github.com/daozhong/STPN.git. 展开更多
关键词 Intelligent transportation system Air traffic network Deviation measurement spatial-temporal path networks Operational monitoring
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Hybrid Bayesian-Machine Learning Framework for Multi-Profile Atmospheric Retrieval from Hyperspectral Infrared Observations
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作者 Senyi KONG Lei BI +2 位作者 Wei HAN Ruoying YIN Honglei ZHANG 《Advances in Atmospheric Sciences》 2026年第2期373-389,共17页
Accurate retrieval of atmospheric vertical profiles is critical for improving weather prediction and climate monitoring.However,the complexity of atmospheric processes in cloudy regions poses challenges compared to th... Accurate retrieval of atmospheric vertical profiles is critical for improving weather prediction and climate monitoring.However,the complexity of atmospheric processes in cloudy regions poses challenges compared to those of clear sky scenarios.This study presents a novel framework that integrates Bayesian optimization and machine learning approaches to retrieve atmospheric vertical profiles—including temperature,humidity,ozone concentration,cloud fraction,ice water content(IWC),and liquid water content(LWC)—from hyperspectral infrared observations.Specifically,a Bayesian method was used to refine ERA5 reanalysis data by minimizing brightness temperature(BT)discrepancies against FY-4B Geostationary Interferometric Infrared Sounder(GIIRS)observations,generating a high-quality profile database(~2.8 million profiles)across diverse weather systems.The optimized profiles improve radiative consistency,reducing BT biases from>40 K to<10 K in cloudy regions.To further overcome the limitations of the Bayesian method,we developed a Transformer-Resnet hybrid model(TERNet),which achieved superior performance with RMSE values of 1.61 K(temperature),5.77%(humidity),and 2.25×10^(–6)/6.09×10^(–6)kg kg^(–1)(IWC/LWC)across the entire vertical levels in all-sky conditions.The TERNet outperforms both ERA5 in cloud parameter retrieval and the GIIRS L2 product in thermodynamic profiling.Independent verification with radiosonde and Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations(CALIPSO)datasets confirms the framework's reliability across various meteorological regimes.This work demonstrates the capability of combining physics-informed Bayesian methods with data-driven machine learning to fully exploit hyperspectral IR data. 展开更多
关键词 BAYESIAN machine learning RETRIEVAL GIIRS atmospheric profile
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Latent Risk-Protection Profiles of Suicidal Ideation in Chinese Adolescents:A Gender-Specific Analysis of Environmental Vulnerability and Individual Resilience
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作者 Xiaoyin Li Ruixiang Gao +2 位作者 Jiaxian Luo Yongxing Guo Pinchao Luo 《International Journal of Mental Health Promotion》 2026年第2期48-67,共20页
Background:Exposure to environmental vulnerability poses significant threats to adolescent suicidal ideation,while individual resilience can mitigate these adverse effects with notable gender commonalities and differe... Background:Exposure to environmental vulnerability poses significant threats to adolescent suicidal ideation,while individual resilience can mitigate these adverse effects with notable gender commonalities and differences.However,research examining how these factors co-configure at the individual level remains limited,particularly from a gender-specific perspective.Thus,the present study aims to adopt a person-centered analytic approach to identify gender-specific configurations of environmental vulnerability and individual resilience associated with suicidal ideation among Chinese adolescents.Methods:Data were collected from 2616 Chinese primary and secondary school students(aged 10–17;1223 girls).Participants completed validated scales measuring environmental vulnerability,individual resilience,and suicidal ideation.Latent profile analysis(LPA)was conducted separately by gender.Results:Gender differences were prominent:males exhibited higher resilience and lower suicidal ideation,while females reported higher environmental vulnerability and elevated levels of suicidal ideation.LPA identified three distinct profiles for males:Low Vulnerable–High Protective–Low Risk(LHL),Medium Vulnerable–Low Protective–Low Risk(MLL),and High Vulnerable–Low Protective–High Risk(HLH).Four profiles emerged for females:LHL,MLL,Medium Vulnerable–Low Protective–Medium Risk(MLM),and HLH.Crucially,within the HLH profile,males exhibited particularly deficient humor(η^(2)=0.19)and confidence(η^(2)=0.16),while females formed a distinct subgroup characterized by severe academic and family stressors(η^(2)=0.30–0.36).Conclusion:The study underscores developing gender-specific mental health interventions using a nuanced,person-centered approach that considers both environmental risk and individual resilience factors,which allows for targeted suicide prevention strategies addressing the unique needs of male and female adolescents. 展开更多
关键词 Environmental vulnerability individual resilience suicidal ideation gender difference latent profile analysis
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Aptamer&MOF-functionalized multichannel paper chip for point-of-care testing of small extracellular vesicle membrane protein profile
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作者 Shaoqiang Wen Lang Zhang +7 位作者 Zhan Huang Meng Chen Yuzhi Xu Xing Huang Zhou Zhang Xiaoyong Zou Zong Dai Si-Yang Liu 《Chinese Chemical Letters》 2026年第2期687-692,共6页
Small extracellular vesicles(sEVs)membrane protein profile(sEVpp)is a novel biomarker for cancer,and it can reveal the in-depth phenotype information.The point-of-care testing(POCT)of sEVpp holds great significance fo... Small extracellular vesicles(sEVs)membrane protein profile(sEVpp)is a novel biomarker for cancer,and it can reveal the in-depth phenotype information.The point-of-care testing(POCT)of sEVpp holds great significance for mass screening of cancer,so the cost-effective and simple detection methods of sEVpp are urgently demanded.Herein,we constructed a paper-based multichannel sEVpp POCT device(sEVpp-PAD)enabled by functional DNA probes and metal-organic framework(MOF).The core components are aptamer/MOF-modified paper chips.The modified aptamers can immunocapture the sEV expressing corresponding proteins,while the modified MOF can provide abundant sites for aptamer-modification,reduce the nonspecific protein absorption,and act as reference for ratiometric detection.Simply powered by two syringes,the sEVpp-PAD can efficiently capture sEVs expressing corresponding protein from cell culture media and sera.Furthermore,a detection probe(DP)consisted of CD63 aptamer and G-quadruplex was developed for the colorimetric detection of captured sEVs.Utilizing this device,the sEVpp in various hepatocellular carcinoma cell culture medium and,more importantly,in human sera can be accurately determined,only with$2 device,$0.2 detection reagents and 1.8 h procedure.This simple strategy for sEVpp detection can innovatively promote the POCT and subtyping of cancer based on sEV-related liquid biopsy. 展开更多
关键词 Small extracellular vesicles Protein profile Point-of-care testing Paper-based analytical device Metal-organic frameworks
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Spatial-temporal distribution and emission of urban scale air pollutants in Hefei based on Mobile-DOAS 被引量:1
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作者 Zhidong Zhang Pinhua Xie +8 位作者 Ang Li Min Qin Jin Xu Zhaokun Hu Xin Tian Feng Hu Yinsheng Lv Jiangyi Zheng Youtao Li 《Journal of Environmental Sciences》 2025年第5期238-251,共14页
As a significant city in the Yangtze River Delta regions,Hefei has experienced rapid changes in the sources of air pollution due to its high-speed economic development and urban expansion.However,there has been limite... As a significant city in the Yangtze River Delta regions,Hefei has experienced rapid changes in the sources of air pollution due to its high-speed economic development and urban expansion.However,there has been limited research in recent years on the spatial-temporal distribution and emission of its atmospheric pollutants.To address this,this study conducted mobile observations of urban roads using the Mobile-DOAS instrument from June 2021 to May 2022.The monitoring results exhibit a favourable consistent with TROPOMI satellite data and ground monitoring station data.Temporally,there were pronounced seasonal variations in air pollutants.Spatially,high concentration of HCHO and NO_(2)were closely associated with traffic congestion on roadways,while heightened SO_(2)levels were attributed to winter heating and industrial emissions.The study also revealed that with the implementation of road policies,the average vehicle speed increased by 95.4%,while the NO concentration decreased by 54.4%.In the estimation of urban NO_(x)emission flux,it was observed that in temporal terms,compared with inventory data,the emissions calculated viamobile measurements exhibitedmore distinct seasonal patterns,with the highest emission rate of 349 g/sec in winter and the lowest of 142 g/sec in summer.In spatial terms,the significant difference in emissions between the inner and outer ring roads also suggests the presence of the city’s primary NO_(x)emission sources in the area between these two rings.This study offers data support for formulating the next phase of air pollution control measures in urban areas. 展开更多
关键词 Mobile-DOAS HCHO NO_(2) SO_(2) spatial-temporal distribution NOx emission
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Observational study to preliminarily characterize the audiological profile of chinese children with williams syndrome 被引量:1
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作者 Jiao Zhang Minghui Zhao +4 位作者 Wei Shi Haina Ding Lan Lan Dayong Wang Qiuju Wang 《Journal of Otology》 2025年第1期5-11,共7页
Purpose It is essential to investigate the audiological profiles of Williams syndrome in a multicultural context.This study aims to examine the characteristics and management of hearing loss in Chinese children with W... Purpose It is essential to investigate the audiological profiles of Williams syndrome in a multicultural context.This study aims to examine the characteristics and management of hearing loss in Chinese children with Williams syndrome and provide references for future clinical management.Method Between January 2007 and March 2022,families with at least 1 WS patient was recruited from the Newborn Cohort Study of Hearing Loss.Audiological tests were performed,and then appropriate medical management was offered.Furthermore,an overview of the hearing loss phenotype in Williams syndrome in different locations was reviewed.Results A total of two families with at least 1 Williams syndrome patient were recruited from the Newborn Cohort Study of Hearing Loss(ChiCTR2100049765).We identified moderately severe sensorineural or conductive hearing loss that emerged as early as the infancy period in Williams syndrome subjects in Chinese children.Our results extended the reported onset ages of hearing loss in WS from late childhood or early adulthood to the infancy period.We also found that with early diagnosis,proper management,and regular monitoring,children with Williams syndrome could return to a normal or near-normal school life.Conclusions Our study demonstrated the distinct hearing profile in Chinese children with Williams syndrome for the first time.This cohort of WS subjects extends the reported onset ages of hearing loss in WS from late childhood or early adulthood to the infancy period,indicating the importance of clinicians screening and monitoring the hearing status of individuals with WS as early as possible.These data provide references for otolaryngologists and paediatricians to inform the clinical understanding and management of hearing loss in Williams syndrome. 展开更多
关键词 williams syndrome hearing loss audiological profile CHILDREN clinical management
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在分子生物学语境中“Profile”的中文翻译分析
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作者 朱梦 《分子植物育种》 北大核心 2025年第15期5067-5072,共6页
本研究试图以分子生物学语料中多义的“profile”为对象,总结和反思中文语境下“profile”的用词现状及相关问题。在翻译过程中出现的不一致情况并非偶然现象,原因是由其本身所处语境的多元以及翻译人员学科背景的差异和受众的不同需求... 本研究试图以分子生物学语料中多义的“profile”为对象,总结和反思中文语境下“profile”的用词现状及相关问题。在翻译过程中出现的不一致情况并非偶然现象,原因是由其本身所处语境的多元以及翻译人员学科背景的差异和受众的不同需求造成的。通过对一些经典的原文进行案例分析,结合相关文献,本研究找出并对比了“profile”在有关基因表达和蛋白功能研究中不同译法的语义差异、利弊以及使用心理,进一步提出了术语翻译的优化路径,旨在确保术语的翻译精准性的同时能够为分子生物学术语的标准化建设提供思路。 展开更多
关键词 分子生物学 术语翻译 profile 语境依赖性 翻译优化策略
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Development of a UAV-borne sorbent tube sampler and its application on the vertical profile measurement of volatile organic compounds 被引量:1
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作者 Haiyue Zhai Jiacheng Zhou +10 位作者 Weixiong Zhao Wanli Du Nana Wei Qianqian Liu Shuo Wang Jianguo Zhang Weihua Cui Weijun Zhang Yanyu Lu Zhu Zhu Yue Liu 《Journal of Environmental Sciences》 2025年第6期276-286,共11页
Vertical detection of volatile organic compounds(VOCs)is essential to expend our understanding of the distribution characteristics of VOCs and improve the predictive ability of existing air qualitymodels.In this work,... Vertical detection of volatile organic compounds(VOCs)is essential to expend our understanding of the distribution characteristics of VOCs and improve the predictive ability of existing air qualitymodels.In this work,we report the development of a sorbent tube sampler based on an unmanned aerial vehicle(UAV)platform.Vertical profile measurement of VOCs with a vertical resolution of 25mwas achieved.The sampler consists of five lightweight VOC sorbent tubes and a 5-way solenoid valve,making it available for collecting five atmospheric VOC samples in a single flight with a time response of less than 30min.The samplerweighed∼1.45 kg and had dimensions of 240mm×220mm×100mmwith small penetration loss(<10%)under 4-liter sampling conditions(flow rate of 200 mL/min).Commercialized SUMMA canisters were used as experimental controls to investigate the possible loss of self-made sampler for target compounds in the same sampling process.Comparison experiment on the ground showed that the concentration differences for all VOC species were lower than 0.14μg/m3,proving the good reliability for VOCs measurements using sorbent tube sampler.The UAV platform also incorporated online instruments for meteorological parameters and O_(3) measurement.The sampler was successfully applied to characterize the vertical profiles of VOCs up to 100 m in October 2023 in the Huaihe River Basin of China.The UAV platform and the sorbent tube sampler demonstrate good performance and will be a valuable and reliable tool for vertical VOCs measurement. 展开更多
关键词 Sorbent tube Unmanned aerial vehicle Vertical profile Volatile organic compounds
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Social alienation in patients with inflammatory bowel diseases:A latent profileanalysis 被引量:1
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作者 Qingyu Wang Junyi Gu +6 位作者 Zheng Lin Sha Li Meijing Zhou Jiefeng Yang Hantian Cheng Jiali Chen Yang Lei 《International Journal of Nursing Sciences》 2025年第4期335-343,I0002,I0003,共11页
Objectives:The study aimed to explore social alienation types in patients with inflammatorybowel diseases(IBD)and identify influencingfactors.Methods:This cross-sectional study was conducted using purposive sampling a... Objectives:The study aimed to explore social alienation types in patients with inflammatorybowel diseases(IBD)and identify influencingfactors.Methods:This cross-sectional study was conducted using purposive sampling among patients with IBD from July 2022 to July 2023.Patients were assessed using the Generalized Social Alienation Scale(GSAS),the Brief Illness Perception Questionnaire(B-IPQ),the Hospital Anxiety and Depression Scale(HADS),and the Medical Coping Modes Questionnaire(MCMQ).Demographic and disease-related characteristics were also collected.Latent profileanalysis(LPA)was used to identify potential subgroups of social alienation.Univariate analysis and multicollinearity analysis were conducted to explore the influencing factors,followed by multiple regression analysis to evaluate the effect of influencingfactors on social alienation.Results:Three distinct profilesof social alienation were identified:integrated-low alienation group(n=61,20.20%),accommodative-moderate alienation group(n=195,64.57%),and maladaptive-high alienation group(n=46,15.23%).Seven characteristics were associated with the profile’smembership:self-perceived financialstress,malnutrition risk,disease duration,illness comprehensibility,anxiety,depression,and acceptance-resignation coping mode.Conclusions:Patients with IBD were categorized into three subgroups based on social alienation levels.Financial stress,malnutrition risk,disease duration,illness comprehensibility,anxiety,depression,and acceptance-resignation coping mode were key predictors of the subgroup membership.Targeted interventions should be developed to mitigate the negative effects of social alienation,with a focus on improving illness perception,alleviating anxiety and depression,and promoting effective coping strategies. 展开更多
关键词 Inflammatory bowel diseases Influencing factors Latent profile analysis NURSING Social alienation
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Multi-Objective Optimization Approach for Achieving Target Profile in Rail Grinding of Worn Rails 被引量:1
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作者 Zhiwei Wu Wengang Fan +2 位作者 Jiang Li Zhiao Liu Jiating Yang 《Chinese Journal of Mechanical Engineering》 2025年第3期463-486,共24页
This research aimed to overcome challenges such as high costs,lengthy optimization time,and low efficiency in resolving issues related to wheel-rail contact,rail wear,and vehicle dynamics.Based on the wheel-rail conta... This research aimed to overcome challenges such as high costs,lengthy optimization time,and low efficiency in resolving issues related to wheel-rail contact,rail wear,and vehicle dynamics.Based on the wheel-rail contact parameters,an optimal design method for rail grinding target profile is proposed from wear profile measurement to grinding profile design according to the actual railway track and vehicle operating conditions.We utilized Isight to create a simulation test and developed an RBF proxy model that incorporated both mechanical and geometric aspects of wheel-rail contact.By integrating rail modeling,wheel-rail contact analysis,and multi-objective optimization,we established a rail grinding optimization model that was solved using the NSGA-II algorithm.After optimization,the study achieved a 31.863%reduction in average contact stress,a 70.5%reduction in matching wear work,and a 100.391%increase in the difference in rolling radius between the wheel and rail. 展开更多
关键词 Rail grinding Optimization of rail profile Rail wear Wheel-rail contact
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Multi-omics profile of exceptional long-term survivors of AJCC stage Ⅲ triple-negative breast cancer 被引量:1
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作者 Yang Ou-Yang Caijin Lin +2 位作者 Yifan Xie Xiaoqing Song Yi-Zhou Jiang 《Chinese Journal of Cancer Research》 2025年第3期316-336,共21页
Objective:Triple-negative breast cancer(TNBC)is a highly aggressive subtype that lacks targeted therapies,leading to a poorer prognosis.However,some patients achieve long-term recurrence-free survival(RFS),offering va... Objective:Triple-negative breast cancer(TNBC)is a highly aggressive subtype that lacks targeted therapies,leading to a poorer prognosis.However,some patients achieve long-term recurrence-free survival(RFS),offering valuable insights into tumor biology and potential treatment strategies.Methods:We conducted a comprehensive multi-omics analysis of 132 patients with American Joint Committee on Cancer(AJCC)stage III TNBC,comprising 36 long-term survivors(RFS≥8 years),62 moderate-term survivors(RFS:3-8 years),and 34 short-term survivors(RFS<3 years).Analyses investigated clinicopathological factors,whole-exome sequencing,germline mutations,copy number alterations(CNAs),RNA sequences,and metabolomic profiles.Results:Long-term survivors exhibited fewer metastatic regional lymph nodes,along with tumors showing reduced stromal fibrosis and lower Ki67 index.Molecularly,these tumors exhibited multiple alterations in genes related to homologous recombination repair,with higher frequencies of germline mutations and somatic CNAs.Additionally,tumors from long-term survivors demonstrated significant downregulation of the RTK-RAS signaling pathway.Metabolomic profiling revealed decreased levels of lipids and carbohydrate,particularly those involved in glycerophospholipid,fructose,and mannose metabolism,in long-term survival group.Multivariate Cox analysis identified fibrosis[hazard ratio(HR):12.70,95%confidence interval(95%CI):2.19-73.54,P=0.005]and RAC1copy number loss/deletion(HR:0.22,95%CI:0.06-0.83,P=0.026)as independent predictors of RFS.Higher fructose/mannose metabolism was associated with worse overall survival(HR:1.30,95%CI:1.01-1.68,P=0.045).Our findings emphasize the association between biological determinants and prolonged survival in patients with TNBC.Conclusions:Our study systematically identified the key molecular and metabolic features associated with prolonged survival in AJCC stage III TNBC,suggesting potential therapeutic targets to improve patient outcomes. 展开更多
关键词 Triple-negative breast cancer long-term survival homologous recombination repair multi-omics analysis metabolic profiling
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High-precision large-aperture single-frame interferometric surface profile measurement method based on deep learning 被引量:1
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作者 Liang Tang Mingzhi Han +3 位作者 Shuai Yang Ye Sun Lirong Qiu Weiqian Zhao 《International Journal of Extreme Manufacturing》 2025年第5期481-492,共12页
Large-aperture optical components are of paramount importance in domains such as integrated circuits,photolithography,aerospace,and inertial confinement fusion.However,measuring their surface profiles relies predomina... Large-aperture optical components are of paramount importance in domains such as integrated circuits,photolithography,aerospace,and inertial confinement fusion.However,measuring their surface profiles relies predominantly on the phase-shifting approach,which involves collecting multiple interferograms and imposes stringent demands on environmental stability.These issues significantly hinder its ability to achieve real-time and dynamic high-precision measurements.Therefore,this study proposes a high-precision large-aperture single-frame interferometric surface profile measurement(LA-SFISPM)method based on deep learning and explores its capability to realize dynamic measurements with high accuracy.The interferogram is matched to the phase by training the data measured using the small aperture.The consistency of the surface features of the small and large apertures is enhanced via contrast learning and feature-distribution alignment.Hence,high-precision phase reconstruction of large-aperture optical components can be achieved without using a phase shifter.The experimental results show that for the tested mirror withΦ=820 mm,the surface profile obtained from LA-SFISPM is subtracted point-by-point from the ground truth,resulting in a maximum single-point error of 4.56 nm.Meanwhile,the peak-to-valley(PV)value is 0.0758λ,and the simple repeatability of root mean square(SR-RMS)value is 0.00025λ,which aligns well with the measured results obtained by ZYGO.In particular,a significant reduction in the measurement time(reduced by a factor of 48)is achieved compared with that of the traditional phase-shifting method.Our proposed method provides an efficient,rapid,and accurate method for obtaining the surface profiles of optical components with different diameters without employing a phase-shifting approach,which is highly desired in large-aperture interferometric measurement systems. 展开更多
关键词 large-aperture optical components single-frame interferometric surface profile deep learning dynamic high-precision measurement
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Towards a blank design method for manufacturing big-tapered profiled ring disk by spinning-rolling process 被引量:1
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作者 Xuechao LI Lianggang GUO +1 位作者 Xiaoqing CHEN Heng LI 《Chinese Journal of Aeronautics》 2025年第1期70-86,共17页
The big-tapered profiled ring disk is a key component of engines for rockets and missiles.A new forming technology,as called spinning-rolling process,has been proposed previously for the high performance,high efficien... The big-tapered profiled ring disk is a key component of engines for rockets and missiles.A new forming technology,as called spinning-rolling process,has been proposed previously for the high performance,high efficiency and low-cost manufacturing of the component.Blank design is the key part of plastic forming process design.For spinning-rolling process,the shape and size of the blank play a crucial role in process stability,deformation behavior and dimensional accuracy.So this work proposes a blank design method to determine the geometry structure and sizes of the blank.The mathematical model for calculating the blank size has been deduced based on volume conservation and neutral layer length invariance principle.The FE simulation and corresponding trial production of an actual big-tapered profiled ring disk show that the proposed blank design method is applicative.In order to obtain a preferred blank,the influence rules of blank size determined by different deformation degrees(rolling ratio k)on the spinning-rolling process are revealed by comprehensive FE simulations.Overall considering the process stability,circularity of the deformed ring disk and forming forces,a reasonable range of deformation degree(rolling ratio k)is recommended for the blank design of the new spinning-rolling process. 展开更多
关键词 Blank design method Spinning-rolling process Big-tapered profiled ring disk Rolling ratio Intelligent FE simulation
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High-Temperature Stable Dispersed Particle Gel for Enhanced Profile Control in Carbon Capture,Utilization,and Storage(CCUS)Applications 被引量:1
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作者 Lin Du Yao-Yu Xiao +2 位作者 Zhi-Chao Jiang Hongbo Zeng Huazhou Li 《Engineering》 2025年第5期128-140,共13页
CO_(2)-responsive gels,which swell upon contact with CO_(2),are widely used for profile control to plug high-permeability gas flow channels in carbon capture,utilization,and storage(CCUS)applications in oil reser-voir... CO_(2)-responsive gels,which swell upon contact with CO_(2),are widely used for profile control to plug high-permeability gas flow channels in carbon capture,utilization,and storage(CCUS)applications in oil reser-voirs.However,the use of these gels in high-temperature CCUS applications is limited due to their rever-sible swelling behavior at elevated temperatures.In this study,a novel dispersed particle gel(DPG)suspension is developed for high-temperature profile control in CCUS applications.First,we synthesize a double-network hydrogel consisting of a crosslinked polyacrylamide(PAAm)network and a crosslinked sodium alginate(SA)network.The hydrogel is then sheared in water to form a pre-prepared DPG suspen-sion.To enhance its performance,the gel particles are modified by introducing potassium methylsilan-etriolate(PMS)upon CO_(2) exposure.Comparing the particle size distributions of the modified and pre-prepared DPG suspension reveals a significant swelling of gel particles,over twice their original size.Moreover,subjecting the new DPG suspension to a 100℃ environment for 24 h demonstrates that its gel particle sizes do not decrease,confirming irreversible swelling,which is a significant advantage over the traditional CO_(2)-responsive gels.Thermogravimetric analysis further indicates improved thermal sta-bility compared to the pre-prepared DPG particles.Core flooding experiments show that the new DPG suspension achieves a high plugging efficiency of 95.3%in plugging an ultra-high permeability sandpack,whereas the pre-prepared DPG suspension achieves only 82.8%.With its high swelling ratio,irreversible swelling at high temperatures,enhanced thermal stability,and superior plugging performance,the newly developed DPG suspension in this work presents a highly promising solution for profile control in high-temperature CCUS applications. 展开更多
关键词 Carbon capture utilization and storage profile control Dispersed particle gel Double-network hydrogel Irreversible swelling
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Segmented predictor-corrector reentry guidance based on an analytical profile 被引量:1
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作者 Hui XU Guangbin CAI +2 位作者 Chaoxu MU Xin LI Hao WEI 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 2025年第1期50-65,共16页
A segmented predictor-corrector method is proposed for hypersonic glide vehicles to address the issue of the slow computational speed of obtaining guidance commands using the traditional predictor-corrector guidance m... A segmented predictor-corrector method is proposed for hypersonic glide vehicles to address the issue of the slow computational speed of obtaining guidance commands using the traditional predictor-corrector guidance method.Firstly,an altitude-energy profile is designed,and the bank angle is derived analytically as the initial iteration value for the predictor-corrector method.The predictor-corrector guidance method has been improved by deriving an analytical form for predicting the range-to-go error,which greatly accelerates the iterative speed.Then,a segmented guidance algorithm is proposed.The above analytically predictor-corrector guidance method is adopted when the energy exceeds an energy threshold.When the energy is less than the threshold,the equidistant test method is used to calculate the bank angle command,which ensures guidance accuracy as well as computational efficiency.Additionally,an adaptive guidance cycle strategy is applied to reduce the computational time of the reentry guidance trajectory.Finally,the accuracy and robustness of the proposed method are verified through a series of simulations and Monte-Carlo experiments.Compared with the traditional integral method,the proposed method requires 75%less computation time on average and achieves a lower landing error. 展开更多
关键词 Hypersonic glide vehicle(HGV) Segmented reentry guidance method Analytical profile Adaptive guidance cycle Reentry trajectory
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Possible Classifications of Social Network Addiction:A Latent Profile Analysis of Chinese College Students 被引量:1
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作者 Lin Luo Junfeng Yuan +4 位作者 Yanling Wang Rui Zhu HuilinXu Siyuan Bi Zhongge Zhang 《International Journal of Mental Health Promotion》 2025年第6期863-876,共14页
Objectives:SocialNetworkAddiction(SNA)is becoming increasingly prevalent among college students;however,there remains a lack of consensus regarding the measurement tools and their optimal cutoff score.This study aims ... Objectives:SocialNetworkAddiction(SNA)is becoming increasingly prevalent among college students;however,there remains a lack of consensus regarding the measurement tools and their optimal cutoff score.This study aims to validate the 21-item SocialNetwork Addiction Scale-Chinese(SNAS-C)in its Chinese version and to determine its optimal cutoff score for identifying potential SNA cases within the college student population.Methods:A crosssectional survey was conducted,recruiting 3387 college students.Latent profile analysis(LPA)and receiver operating characteristic(ROC)curve analysis were employed to establish the optimal cutoff score for the validated 21-item SNAS-C.Results:Three profile models were selected based on multiple statistical criteria,classifying participants into low-risk,moderate-risk,and high-risk groups.The highest-risk group was defined as“positive”for SNA,while the remaining groups were considered“negative”,serving as the reference standard for ROC analysis.The optimal cutoff score was determined to be 72(sensitivity:98.2%,specificity:96.86%),with an overall classification accuracy of 97.0%.The“positive”group reported significantly higher frequency of social network usage,greater digitalmedia dependence scores,and a higher incidence of network addiction.Conclusion:This study identified the optimal cutoff score for the SNAS-C as≥72,demonstrating high sensitivity,specificity,and diagnostic accuracy.This threshold effectively distinguishes between high-risk and low-risk SNA. 展开更多
关键词 Social network addiction mental health latent profile analysis(LPA) receiver operating characteristic(ROC) social networking addiction scale-Chinese(SNAS-C)
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Modified Flash Profile评价方法在面霜气味情绪研究中的应用
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作者 储丽玲 齐荣 程党党 《香料香精化妆品》 2025年第4期99-103,共5页
通过modified Flash Profile(mFP)方法评价了8款市售面霜气味的情绪感知,结果表明mFP方法可以区分面霜气味带来的不同情绪:面霜产品748和837的气味令人愉悦、放松、舒适和平静,产品901与之相反;面霜产品139和563的气味被认为平静的;添... 通过modified Flash Profile(mFP)方法评价了8款市售面霜气味的情绪感知,结果表明mFP方法可以区分面霜气味带来的不同情绪:面霜产品748和837的气味令人愉悦、放松、舒适和平静,产品901与之相反;面霜产品139和563的气味被认为平静的;添加香精的面霜产品748、837和205比未添加香精的面霜产品901、139和563更能让人感觉舒适、放松、愉悦。情绪评定量表的评价结果与mFP方法相似。2种方法的RV系数是0.899,高度相关,2种评价方法的结果可以互相验证,为化妆品气味的情绪探索提供一些思路。 展开更多
关键词 面霜气味 情绪 modified Flash profile 情绪评定量表
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Spatial-Temporal Coupling and Determinants of Digital Economy and High-Quality Development: Insights from the Yellow River Region
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作者 Zhang Shu Wang Kangqing Guo Jinlong 《全球城市研究(中英文)》 2025年第2期1-17,149,共18页
In the current situation of decelerating economic expansion,examining the digital economy(DE)as a novel economic model is beneficial for the local economy’s sustainable and high-quality development(HQD).We analyzed p... In the current situation of decelerating economic expansion,examining the digital economy(DE)as a novel economic model is beneficial for the local economy’s sustainable and high-quality development(HQD).We analyzed panel data from the Yellow River(YR)region from 2013 to 2021 and discovered notable spatial variances in the composite index and coupling coordination of the two systems.Specifically,the downstream region exhibited the highest coupling coordination,while the upstream region had the lowest.We identified that favorable factors such as economic development,innovation,industrial upgrading,and government intervention can bolster the coupling.Our findings provide a valuable framework for promoting DE and HQD in the YR region. 展开更多
关键词 High-quality development Digital economy spatial-temporal coupling the Yellow River region
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MSSTGCN: Multi-Head Self-Attention and Spatial-Temporal Graph Convolutional Network for Multi-Scale Traffic Flow Prediction
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作者 Xinlu Zong Fan Yu +1 位作者 Zhen Chen Xue Xia 《Computers, Materials & Continua》 2025年第2期3517-3537,共21页
Accurate traffic flow prediction has a profound impact on modern traffic management. Traffic flow has complex spatial-temporal correlations and periodicity, which poses difficulties for precise prediction. To address ... Accurate traffic flow prediction has a profound impact on modern traffic management. Traffic flow has complex spatial-temporal correlations and periodicity, which poses difficulties for precise prediction. To address this problem, a Multi-head Self-attention and Spatial-Temporal Graph Convolutional Network (MSSTGCN) for multiscale traffic flow prediction is proposed. Firstly, to capture the hidden traffic periodicity of traffic flow, traffic flow is divided into three kinds of periods, including hourly, daily, and weekly data. Secondly, a graph attention residual layer is constructed to learn the global spatial features across regions. Local spatial-temporal dependence is captured by using a T-GCN module. Thirdly, a transformer layer is introduced to learn the long-term dependence in time. A position embedding mechanism is introduced to label position information for all traffic sequences. Thus, this multi-head self-attention mechanism can recognize the sequence order and allocate weights for different time nodes. Experimental results on four real-world datasets show that the MSSTGCN performs better than the baseline methods and can be successfully adapted to traffic prediction tasks. 展开更多
关键词 Graph convolutional network traffic flow prediction multi-scale traffic flow spatial-temporal model
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