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Effects of cement-enhanced soil on the ultimate lateral resistance of composite pile in clayey soil
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作者 Zhijun Yang kexin chen +1 位作者 Xudong Fu Zhiyan Zou 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第1期183-191,共9页
The composite pile consisting of core-pile and surrounding cement-enhanced soil is a promising pile foundation in recent years.However,how and to what extent the cement-enhanced soil influences the ultimate lateral re... The composite pile consisting of core-pile and surrounding cement-enhanced soil is a promising pile foundation in recent years.However,how and to what extent the cement-enhanced soil influences the ultimate lateral resistance has not been fully investigated.In this paper,the ultimate lateral resistance of the composite pile was studied by finite element limit analysis(FELA)and theoretical upper-bound analysis.The results of FELA and theoretical analysis revealed three failure modes of laterally loaded composite piles.The effects of the enhanced soil thickness,strength,and pile-enhanced soil interface characteristics on the ultimate lateral resistance were studied.The results show that increasing the enhanced soil thickness leads to a significant improvement on ultimate lateral resistance factor(N P),and there is a critical thickness beyond which the thickness no longer affects the N P.Increasing the enhanced soil strength induced 6.2%-232.6%increase of N P.However,no noticeable impact was detected when the enhanced soil strength was eight times higher than that of the natural soil.The maximum increment of N P is only 30.5%caused by the increase of interface adhesion factor(a).An empirical model was developed to calculate the N P of the composite pile,and the results show excellent agreement with the analytical results. 展开更多
关键词 Composite pile Ultimate soil resistance Finite element limit analysis(FELA) Plasticity theory Failure mode
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Crossing the Achilles Heel of Algorithms:Identifying the Developmental Dilemma of Artificial Intelligence-Assisted Judicial Decision-Making
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作者 kexin chen 《Journal of Electronic Research and Application》 2024年第1期69-72,共4页
In the developmental dilemma of artificial intelligence(AI)-assisted judicial decision-making,the technical architecture of AI determines its inherent lack of transparency and interpretability,which is challenging to ... In the developmental dilemma of artificial intelligence(AI)-assisted judicial decision-making,the technical architecture of AI determines its inherent lack of transparency and interpretability,which is challenging to fundamentally improve.This can be considered a true challenge in the realm of AI-assisted judicial decision-making.By examining the court’s acceptance,integration,and trade-offs of AI technology embedded in the judicial field,the exploration of potential conflicts,interactions,and even mutual shaping between the two will not only reshape their conceptual connotations and intellectual boundaries but also strengthen the cognition and re-interpretation of the basic principles and core values of the judicial trial system. 展开更多
关键词 Artificial intelligence Automated decision-making Algorithmic law system Due process Algorithmic justice
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Developing allometric equations to estimate forest biomass for tree species categories based on phylogenetic relationships
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作者 Mingxia Yang Xiaolu Zhou +7 位作者 Changhui Peng Tong Li kexin chen Zelin Liu Peng Li Cicheng Zhang Jiayi Tang Ziying Zou 《Forest Ecosystems》 SCIE CSCD 2023年第4期494-503,共10页
The development of allometric biomass models is important process in biomass estimation because the reliability of forest biomass and carbon estimations largely depends on the accuracy and precision of such models.Nat... The development of allometric biomass models is important process in biomass estimation because the reliability of forest biomass and carbon estimations largely depends on the accuracy and precision of such models.National Forest Inventories(NFI)are detailed assessments of forest resources at national and regional levels that provide valuable data for forest biomass estimation.However,the lack of biomass allometric equations for each tree species in the NFI currently hampers the estimation of national-scale forest biomass.The main objective of this study was to develop allometric biomass regression equations for each tree species in the NFI of China based on limited biomass observations.These equations optimally grouped NFI and biomass observation species according to their phylogenetic relationships.Significant phylogenetic signals demonstrated phylogenetic conservation of the crown-to-stem biomass ratio.Based on phylogenetic relationships,we grouped and matched NFI and biomass observation species into 22 categories.Allometric biomass regression models were developed for each of these 22 species categories,and the models performed successfully(R^(2)=0.97,root mean square error(RMSE)=12.9​t·ha^(–1),relative RMSE=11.5%).Furthermore,we found that phylogeny-based models performed more effectively than wood density-based models.The results suggest that grouping species based on their phylogenetic relationships is a reliable approach for the development and selection of accurate allometric equations. 展开更多
关键词 Allometric equation Forest biomass National Forest Inventory Species grouping Tree architecture Wood density
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Modulation of the Wind Field Structure of Initial Vortex on the Relationship between Tropical Cyclone Size and Intensity
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作者 kexin chen Guanghua chen Donglei SHI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第9期1707-1721,共15页
This study investigates the modulation of initial wind field structure on the relationship between the size and intensity of a simulated vortex.A series of idealized experiments are conducted by varying the radius of ... This study investigates the modulation of initial wind field structure on the relationship between the size and intensity of a simulated vortex.A series of idealized experiments are conducted by varying the radius of maximum wind(RMW)and shape parameter of the initial vortices.The size–intensity relationship is quantified by the linear regression coefficient of the azimuthally-averaged gale-force wind radius against the maximum wind during the development stage,reflecting the degree of size expansion at the same intensity increment.The regression coefficient increases with increased RMW and decreased,with the RMW being the primary constraint.The effect of lowering on the elevation of the regression coefficient gradually stands out when the initial RMW is large.Enlarging the RMW leads to a secondary circulation with a horizontally elongated structure,which retards the intensification while promoting size expansion,thus substantially enhancing size expansion as the vortex intensifies.Broadening the wind field outside the RMW by reducing results in abounding convection in the outer region,which promotes size expansion.Based on the axisymmetric tangential wind tendency and Sawyer–Eliassen equations,when the RMW is large,the active convection in the outer region can weaken the radial inflow induced by the eyewall heating in the inner region,thus retarding the intensification by reducing the radial imports of vorticity near the RMW. 展开更多
关键词 tropical cyclone size and intensity initial wind field structure tangential wind tendency equation Sawyer-Eliassen equation
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Cohort profile: design and methods of the Chinese colorectal, breast, lung, liver, and stomach cancer screening trial(C-BLAST)
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作者 Yubei Huang Zhangyan Lyu +20 位作者 Yu Zhang Xiaomin Liu Yacong Zhang Ya Liu Chao Sheng Hongyuan Duan Zeyu Fani chenyang Li Xiao Lin Zhuowei Feng Lu Zheng Zhaoxiang Ye Hong Lu Ying Zhu Dejun Zhou Xi Wei Li Ren Bin Meng Fangfang Song Fengju Song kexin chen 《Cancer Biology & Medicine》 SCIE CAS CSCD 2023年第10期713-720,共8页
Given the rapid changes in social structure(urbanization),economic structure(industrialization),and demographic structure(population aging)in China,cancer has become a major public health problem1.Extensive evidence h... Given the rapid changes in social structure(urbanization),economic structure(industrialization),and demographic structure(population aging)in China,cancer has become a major public health problem1.Extensive evidence has indicated that screening can decrease cancer mortality,particularly among high-risk groups,and several representative national and regional cancer screening programs have been launched in China to cope with the increasing burden of cancer. 展开更多
关键词 STOMACH cancer mortality
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《中国女性乳腺癌筛查指南》解读(精简版) 被引量:53
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作者 黄育北 佟仲生 +11 位作者 陈可欣 王瑛 刘佩芳 顾林 刘俊田 于津浦 宋丰举 赵文华 史业辉 李慧 肖怀远 郝希山 《中国肿瘤临床》 CAS CSCD 北大核心 2019年第9期432-440,共9页
乳腺癌是中国女性最常见的恶性肿瘤,早期筛查是提高乳腺癌早诊早治最佳途径。中国女性乳腺癌发病高峰年龄与欧美国家乳腺癌发病高峰年龄明显不同,制定适合中国女性特点的群体性乳腺癌筛查指南势在必行。中国抗癌协会与国家肿瘤临床医学... 乳腺癌是中国女性最常见的恶性肿瘤,早期筛查是提高乳腺癌早诊早治最佳途径。中国女性乳腺癌发病高峰年龄与欧美国家乳腺癌发病高峰年龄明显不同,制定适合中国女性特点的群体性乳腺癌筛查指南势在必行。中国抗癌协会与国家肿瘤临床医学研究中心(天津医科大学肿瘤医院)组织专家在分析总结中国女性乳腺癌筛查数据的基础上,参考欧美及东亚等国家的最新乳腺癌筛查指南或共识,分别从筛查起始年龄、筛查方法、筛查时间间隔3个方面,针对中国女性乳腺癌一般风险人群和高危风险人群制定以人群为基础的《中国女性乳腺癌筛查指南》,本文对该指南进行解读以供乳腺癌筛查相关人士参考。 展开更多
关键词 乳腺癌 筛查 指南
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Interpretation of breast cancer screening guideline for Chinese women 被引量:11
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作者 Yubei Huang Zhongsheng Tong +11 位作者 kexin chen Ying Wang Peifang Liu Lin Gu Juntian Liu Jinpu Yu Fengju Song Wenhua Zhao Yehui Shi Hui Li Huaiyuan Xiao Xishan Hao 《Cancer Biology & Medicine》 SCIE CAS CSCD 2019年第4期825-835,共11页
Breast cancer is the most common malignant tumor in Chinese women.Early screening is the best way to improve the rates of early diagnosis and survival of breast cancer patients.The peak onset age for breast cancer in ... Breast cancer is the most common malignant tumor in Chinese women.Early screening is the best way to improve the rates of early diagnosis and survival of breast cancer patients.The peak onset age for breast cancer in Chinese women is considerably younger than those in European and American women.It is imperative to develop breast cancer screening guideline that is suitable for Chinese women.By summarizing the current evidence on breast cancer screening in Chinese women,and referring to the latest guidelines and consensus on breast cancer screening in Europe,the United States,and East Asia,the China Anti-Cancer Association and National Clinical Research Center for Cancer(Tianjin Medical University Cancer Institute and Hospital)have formulated population-based guideline for breast cancer screening in Chinese women.The guideline provides recommendations on breast cancer screening for Chinese women at average or high risk of breast cancer according to the following three aspects:age of screening,screening methods,and screening interval.This article provides more detailed information to support the recommendations in this guideline and to provide more direction for current breast cancer screening practices in China. 展开更多
关键词 Breast cancer screening ULTRASOUND MAMMOGRAPHY GUIDELINE
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Methods of computed tomography screening and management of lung cancer in Tianjin: design of a population-based cohort study 被引量:7
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作者 Yihui Du Yingru Zhao +13 位作者 Grigory Sidorenkov Geertruida H.de Bock Xiaonan Cui Yubei Huang Monique D.Dorrius Mieneke Rook Harry J.M.Groen Marjolein A.Heuvelmans Rozemarijn Vliegenthart kexin chen Xueqian Xie Shiyuan Liu Matthijs Oudkerk Zhaoxiang Ye 《Cancer Biology & Medicine》 SCIE CAS CSCD 2019年第1期181-188,共8页
Objective: European lung cancer screening studies using computed tomography(CT) have shown that a management protocol based on measuring lung nodule volume and volume doubling time(VDT) is more specific for early lung... Objective: European lung cancer screening studies using computed tomography(CT) have shown that a management protocol based on measuring lung nodule volume and volume doubling time(VDT) is more specific for early lung cancer detection than a diameter-based protocol. However, whether this also applies to a Chinese population is unclear. The aim of this study is to compare the diagnostic performance of a volume-based protocol with a diameter-based protocol for lung cancer detection and optimize the nodule management criteria for a Chinese population.Methods: This study has a population-based, prospective cohort design and includes 4000 participants from the Hexi district of Tianjin, China. Participants will undergo low-dose chest CT at baseline and after 1 year. Initially, detected lung nodules will be evaluated for diameter and managed according to a routine diameter-based protocol(Clinical Practice Guideline in Oncology for Lung Cancer Screening, Version 2.2018). Subsequently, lung nodules will be evaluated for volume and management will be simulated according to a volume-based protocol and VDT(a European lung nodule management protocol). Participants will be followed up for 4 years to evaluate lung cancer incidence and mortality. The primary outcome is the diagnostic performance of the European volume-based protocol compared to diameter-based management regarding lung nodules detected using low-dose CT.Results: The diagnostic performance of volume-and diameter-based management for lung nodules in a Chinese population will be estimated and compared.Conclusions: Through the study, we expect to improve the management of lung nodules and early detection of lung cancer in Chinese populations. 展开更多
关键词 LUNG cancer LUNG NODULES SCREENING COMPUTED tomography China
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Roles of low?density lipoproteinreceptor?related protein 1 in tumors 被引量:4
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作者 Peipei Xing Zhichao Liao +5 位作者 Zhiwu Ren Jun Zhao Fengju Song Guowen Wang kexin chen Jilong Yang 《Chinese Journal of Cancer》 SCIE CAS CSCD 2016年第1期4-11,共8页
Low-density lipoprotein receptor-related protein 1(LRP1,also known as CD91),a multifunctional endocytic and cell signaling receptor,is widely expressed on the surface of multiple cell types such as hepatocytes,fibrobl... Low-density lipoprotein receptor-related protein 1(LRP1,also known as CD91),a multifunctional endocytic and cell signaling receptor,is widely expressed on the surface of multiple cell types such as hepatocytes,fibroblasts,neurons,astrocytes,macrophages,smooth muscle cells,and malignant cells.Emerging in vitro and in vivo evidence demonstrates that LRP1 is critically involved in many processes that drive tumorigenesis and tumor progression.For example,LRP1 not only promotes tumor cell migration and invasion by regulating matrix metalloproteinase(MMP)-2and MMP-9 expression and functions but also inhibits cell apoptosis by regulating the insulin receptor,the serine/threonine protein kinase signaling pathway,and the expression of Caspase-3.LRPI-mediated phosphorylation of the extracellular signal-regulated kinase pathway and c-jun N-terminal kinase are also involved in tumor cell proliferation and invasion.In addition,LRP1 has been shown to be down-regulated by microRNA-205 and methylation of LRP1CpG islands.Furthermore,a novel fusion gene,LRP1-SNRNP25,promotes osteosarcoma cell invasion and migration.Only by understanding the mechanisms of these effects can we develop novel diagnostic and therapeutic strategies for cancers mediated by LRP1. 展开更多
关键词 LOW-DENSITY LIPOPROTEIN receptor-related PROTEIN 1 Tumorigenesis Invasion migration Proliferation apoptosis Signaling pathway MicroRNA Fusion gene
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Evaluation of Two Initialization Schemes for Simulating the Rapid Intensification of Typhoon Lekima (2019) 被引量:2
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作者 Donglei SHI Guanghua chen +2 位作者 Ke WANG Xinxin BI kexin chen 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2020年第9期987-1006,共20页
Two different initialization schemes for tropical cyclone(TC)prediction in numerical models are evaluated based on a case study of Typhoon Lekima(2019).The first is a dynamical initialization(DI)scheme where the axisy... Two different initialization schemes for tropical cyclone(TC)prediction in numerical models are evaluated based on a case study of Typhoon Lekima(2019).The first is a dynamical initialization(DI)scheme where the axisymmetric TC vortex in the initial conditions is spun up through the 6-h cycle runs before the initial forecast time.The second scheme is a bogussing scheme where the analysis TC vortex is replaced by a synthetic Rankine vortex.Results show that although both initialization schemes can help improve the simulated rapid intensification(RI)of Lekima,the simulation employing the DI scheme(DIS)reproduces better the RI onset and intensification rate than that employing the bogussing scheme(BOG).Further analyses show the cycle runs of DI help establish a realistic TC structure with stronger secondary circulation than those in the control run and BOG,leading to fast vortex spinup and contraction of the radius of maximum wind(RMW).The resultant strong inner-core primary circulation favors precession of the midlevel vortex under the moderate vertical wind shear(VWS)and thus helps vortex alignment,contributing to an earlier RI onset.Afterwards,the decreased vertical shear and the stronger convection inside the RMW support the persistent RI of Lekima in DIS.In contrast,the reduced VWS is not well captured and the inner-core convection is weaker and resides farther away from the TC center in BOG,leading to slower intensification.The results imply that the DI effectively improves the prediction of the inner-core process,which is crucial to the RI forecast. 展开更多
关键词 numerical simulation initialization scheme tropical cyclone intensity
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Living biobank-based cancer organoids: prospects and challenges in cancer research 被引量:1
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作者 Haixin Li Hongkun Liu kexin chen 《Cancer Biology & Medicine》 SCIE CAS CSCD 2022年第7期965-982,共18页
Biobanks bridge the gap between basic and translational research.Traditional cancer biobanks typically contain normal and tumor tissues,and matched blood.However,biospecimens in traditional biobanks are usually nonren... Biobanks bridge the gap between basic and translational research.Traditional cancer biobanks typically contain normal and tumor tissues,and matched blood.However,biospecimens in traditional biobanks are usually nonrenewable.In recent years,increased interest has focused on establishing living biobanks,including organoid biobanks,for the collection and storage of viable and functional tissues for long periods of time.The organoid model is based on a 3D in vitro cell culture system,is highly similar to primary tissues and organs in vivo,and can recapitulate the phenotypic and genetic characteristics of target organs.Publications on cancer organoids have recently increased,and many types of cancer organoids have been used for modeling cancer processes,as well as for drug discovery and screening.On the basis of the current research status,more exploration of cancer organoids through technical advancements is required to improve reproducibility and scalability.Moreover,given the natural characteristics of organoids,greater attention must be paid to ethical considerations.Here,we summarize recent advances in cancer organoid biobanking research,encompassing rectal,gastric,pancreatic,breast,and glioblastoma cancers.Living cancer biobanks that contain cancerous tissues and matched organoids with different genetic backgrounds,subtypes,and individualized characteristics will eventually contribute to the understanding of cancer and ultimately facilitate the development of innovative treatments. 展开更多
关键词 Cancer organoids living biobanks BIOBANK preclinical models
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The efficacies and biomarker investigations of antiprogrammed death-1 (anti-PD-1)-based therapies for metastatic bone and soft tissue sarcoma
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作者 Jia Lu Ting Li +12 位作者 Zhichao Liao Hui Yu Yongtian Zhao Haixiao Wu Zhiwu Ren Jun Zhao Ruwei Xing Sheng Teng Yun Yang Xiangchun Li kexin chen Jonathan Trent Jilong Yang 《Cancer Biology & Medicine》 SCIE CAS CSCD 2022年第6期910-930,共21页
Objective:Sarcomas are a group of rare malignancies with various subtypes.Patients with metastatic sarcoma who have failed traditional treatments can possibly achieve better prognoses from using novel therapies,includ... Objective:Sarcomas are a group of rare malignancies with various subtypes.Patients with metastatic sarcoma who have failed traditional treatments can possibly achieve better prognoses from using novel therapies,including anti-programmed death-1(PD-1)-based therapies.Methods:We retrospectively analyzed clinical data of 24 metastatic sarcoma patients from June 15,2016 to December 30,2019.These patients mainly received angiogenesis inhibitors combined with anti-PD-1 therapy after they became resistant to traditional treatments.Furthermore,8 patients underwent panel DNA and whole transcript sequencing.Results:Six patients received 2 cycles of anti-PD-1 therapy and were included in the safety evaluation only group.The median follow-up time was 5.77 months.The median progression-free survival was 7.59 months,the overall response rate was 16.7%and the disease control rate was 55.6%.Based on whole exome and transcript sequencing data,there was no association between TMB,TNB,MSI,HLA-LOH,and PD-L1 expressions and sarcoma types with clinical responses.Immunotherapy efficacy and bioinformatics analyses indicated higher intratumoral heterogeneity(ITH)in progressive disease(PD)patients and lower ITH in partial response(PR)and stable disease patients.A higher percentage of immune cell infiltration,especially monocytes,was observed in PR patients.Active stromal gene expression was increased in PD patients but decreased in PR patients.Enrichment analysis revealed that an increased TGF-βsignaling pathway was reversely correlated with anti-PD-1 efficacy,while a decreased inflammatory response signaling pathway was positively correlated with anti-PD-1 efficacy.Conclusions:Our study showed PD-1 inhibitors combined with anti-angiogenesis agents were effective and well-tolerated.ITH,monocyte ratio,stroma subtypes,and the status of immune-associated signaling pathways may be related with anti-PD-1 based therapy. 展开更多
关键词 SARCOMA PD-1 PD-L1 IMMUNOTHERAPY angiogenesis safety efficacy BIOMARKER
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Development and evaluation of the screening performance of a low-cost high-risk screening strategy for breast cancer
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作者 Yubei Huang Huan Wang +5 位作者 Zhangyan Lyu Hongji Dai Peifang Liu Ying Zhu Fengju Song kexin chen 《Cancer Biology & Medicine》 SCIE CAS CSCD 2022年第9期1375-1384,共10页
Objective:To develop and evaluate the screening performance of a low-cost high-risk screening strategy for breast cancer in low resource areas.Methods:Based on the Multi-modality Independent Screening Trial,6 question... Objective:To develop and evaluate the screening performance of a low-cost high-risk screening strategy for breast cancer in low resource areas.Methods:Based on the Multi-modality Independent Screening Trial,6 questionnaire-based risk factors of breast cancer(age at menarche,age at menopause,age at first live birth,oral contraceptive,obesity,family history of breast cancer)were used to determine the women with high risk of breast cancer.The screening performance of clinical breast examination(CBE),breast ultrasonography(BUS),and mammography(MAM)were calculated and compared to determine the optimal screening method for these high risk women.Results:A total of 94 breast cancers were detected among 31,720 asymptomatic Chinese women aged 45–65 years.Due to significantly higher detection rates(DRs)and suitable coverage of the population,high risk women were defined as those with any of 6 risk factors.Among high risk women,the DR for BUS[3.09/1,000(33/10,694)]was similar to that for MAM[3.18/1,000(34/10,696)],while it was significantly higher than that for the CBE[1.73/1,000(19/10,959),P=0.002].Compared with MAM,BUS showed significantly higher specificity[98.64%(10,501/10,646)vs.98.06%(10,443/10,650),P=0.001],but no significant differences in sensitivity[68.75%(33/48)vs.73.91%(34/46)],positive prediction values[18.54%(33/178)vs.14.11%(34/241)],and negative prediction values[99.86%(10,501/10,516)vs.99.89%(10,443/10,455)].Further analyses showed no significant difference in the percentages of early stage breast cancer[53.57%(15/28)vs.50.00%(15/30)],lymph node involvement[22.73%(5/22)vs.28.00%(7/25)],and tumor size≥2 cm[37.04%(10/27)vs.29.03%(9/31)]between BUS and MAM.Subgroup analyses stratified by breast densities or age at enrollment showed similar results.Conclusions:The low-cost high-risk screening strategy based on 6 questionnaire-based risk factors was an easy-to-use method to identify women with high risk of breast cancer.Moreover,BUS and MAM had comparable screening performances among high risk women. 展开更多
关键词 Cancer screening breast cancer high risk MAMMOGRAPHY ULTRASONOGRAPHY
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Reexamination of the Relationship between Tropical Cyclone Size and Intensity over the Western North Pacific
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作者 kexin chen Guanghua chen Donglei SHI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2022年第11期1956-1968,共13页
This study reexamines the correlation between the size and intensity of tropical cyclones(TCs) over the western North Pacific from the perspective of individual TCs, rather than the previous large-sample framework mix... This study reexamines the correlation between the size and intensity of tropical cyclones(TCs) over the western North Pacific from the perspective of individual TCs, rather than the previous large-sample framework mixing up all TC records.Statistics show that the positive size-intensity correlation based on individual TCs is relatively high. However, this correlation is obscured by mixing large samples. The weakened correlation based on all TC records is primarily due to the diversity in the size change relative to the same intensity change among TCs, which can be quantitatively measured by the linear regression coefficient(RC) of size against intensity. To further explore the factors that cause the variability in RCs that weakens the size-intensity correlation when considering all TC records, the TCs from 2001 to 2020 are classified into two groups according to their RC magnitudes, within which the high-RC TCs have a larger size expansion than the low-RC TCs given the same intensity change. Two key mechanisms responsible for the RC differences are proposed. First, the highRC TCs are generally located at higher latitudes than the low-RC TCs, resulting in higher planetary vorticity and thus higher planetary angular momentum import at low levels. Second, the high-RC TCs are susceptible to stronger environmental vertical wind shear, leading to more prolific outer convection than the low-RC TCs. The positive feedback between outer diabatic heating and boundary layer inflow favors the inward import of absolute angular momentum in the outer region, thereby contributing to a larger size expansion in the high-RC TCs. 展开更多
关键词 tropical cyclone size and intensity composite analysis absolute angular momentum flux budget
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Improved diagnosis of thyroid cancer aided with deep learning applied to sonographic text reports:a retrospective,multi-cohort,diagnostic study
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作者 Qiang Zhang Sheng Zhang +32 位作者 Jianxin Li Yi Pan Jing Zhao Yixing Feng Yanhui Zhao Xiaoqing Wang Zhiming Zheng Xiangming Yang Lixia Liu Chunxin Qin Ke Zhao Xiaonan Liu Caixia Li Liuyang Zhang Chunrui Yang Na Zhuo Hong Zhang Jie Liu Jinglei Gao Xiaoling Di Fanbo Meng Wei Ji Meng Yang Xiaojie Xin Xi Wei Rui Jin Lun Zhang Xudong Wang Fengju Song Xiangqian Zheng Ming Gao kexin chen Xiangchun Li 《Cancer Biology & Medicine》 SCIE CAS CSCD 2022年第5期733-741,共9页
Objective:Large volume radiological text data have been accumulated since the incorporation of electronic health record(EHR)systems in clinical practice.We aimed to determine whether deep natural language processing a... Objective:Large volume radiological text data have been accumulated since the incorporation of electronic health record(EHR)systems in clinical practice.We aimed to determine whether deep natural language processing algorithms could aid radiologists in improving thyroid cancer diagnosis.Methods:Sonographic EHR data were obtained from the EHR database.Pathological reports were used as the gold standard for diagnosing thyroid cancer.We developed thyroid cancer diagnosis based on natural language processing(THCaDxNLP)to interpret unstructured sonographic text reports for thyroid cancer diagnosis.We used the area under the receiver operating characteristic curve(AUROC)as the primary metric to measure the performance of the THCaDxNLP.We compared the performance of thyroid ultrasound radiologists aided with THCaDxNLP vs.those without THCaDxNLP using 5 independent test sets.Results:We obtained a total number of 788,129 sonographic radiological reports.The number of thyroid sonographic data points was 132,277,18,400 of which were thyroid cancer patients.Among the 5 test sets,the numbers of patients per set were 439,186,82,343,and 171.THCaDxNLP achieved high performance in identifying thyroid cancer patients(the AUROC ranged from 0.857–0.932).Thyroid ultrasound radiologists aided with THCaDxNLP achieved significantly higher performances than those without THCaDxNLP in terms of accuracy(93.8%vs.87.2%;one-sided t-test,adjusted P=0.003),precision(92.5%vs.86.0%;P=0.018),and F1 metric(94.2%vs.86.4%;P=0.007).Conclusions:THCaDxNLP achieved a high AUROC for the identification of thyroid cancer,and improved the accuracy,sensitivity,and precision of thyroid ultrasound radiologists.This warrants further investigation of THCaDxNLP in prospective clinical trials. 展开更多
关键词 Thyroid cancer sonographic text report deep learning natural language process
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西北太平洋上热带气旋尺度变化率与其尺度和强度的关系
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作者 kexin chen Guanghua chen +1 位作者 chenhong Rao Ziqing Wang 《Atmospheric and Oceanic Science Letters》 CSCD 2021年第3期36-41,共6页
为了进一步了解热带气旋(TC)尺度变化与其结构的相关关系,本文基于多平台热带气旋表面风场资料,通过相关分析得出西北太平洋上TC的24 h尺度变化率(SCR)与其尺度,强度以及强度变化率(ICR)的相关系数分别为–0.43,–0.12,0.25.其中SCR-IC... 为了进一步了解热带气旋(TC)尺度变化与其结构的相关关系,本文基于多平台热带气旋表面风场资料,通过相关分析得出西北太平洋上TC的24 h尺度变化率(SCR)与其尺度,强度以及强度变化率(ICR)的相关系数分别为–0.43,–0.12,0.25.其中SCR-ICR的相关关系主要受不同发展阶段的影响,在TC均达到/均未达到最大尺度和最强强度的阶段中,SCR-ICR的相关系数上升至0.40,表明在这些阶段中ICR是预报SCR的潜在因子之一.当TC尺度较小(大)和强度较弱(强)时其尺度更易扩张(收缩). 展开更多
关键词 热带气旋 尺度变化率 多平台热带气旋表面风场资料 相关分析
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Effect of Homogenizing Procedures on the Properties of Reaction Sialon Suspension
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作者 Xavier Venceslau kexin chen José M F Ferreira 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期132-133,共2页
Homogeneous, high concentrated ceramic suspensions wi th low viscosity are the key controlling factors for the production of ceramic c omponents through colloidal processing. A well-dispersed suspension can be obta in... Homogeneous, high concentrated ceramic suspensions wi th low viscosity are the key controlling factors for the production of ceramic c omponents through colloidal processing. A well-dispersed suspension can be obta ined by choosing suitable dispersant, solvent, particle size distribution etc. B esides these factors, the homogenizing procedure is also a key step. In this paper, reaction sialon suspensions were prepared using 3-wt% KD1 as dis persant in organic media composed of 60-vol% methyletheylketone and 40-vol% et hanol. Different homogenizing procedures have been used and compared, including planetary milling, low energy ball milling and ultrasonic disaggregation. The ef fects of different homogenizing routes and mixing times on the rheology and stab ility of suspensions, and on the microstructure of slip casting green bodies, ha ve been studied. The varying dispersion efficiencies observed could be attribute d to differences in deagglomeration degrees achieved and in adsorption amount of dispersant onto the surface of reaction sialon powders. 展开更多
关键词 Effect of Homogenizing Procedures on the Properties of Reaction Sialon Suspension
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Economic Policy Uncertainty and Corporate Mergers and Acquisitions
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作者 Xun Han kexin chen Xianjing Huang 《Journal of Economic Science Research》 2020年第4期24-39,共16页
In recent years,the frequent adjustment of the government’s economic policies and the uncertainty of foreign economic situations have made the degree of uncertainty of China’s economic policies rise continuously.The... In recent years,the frequent adjustment of the government’s economic policies and the uncertainty of foreign economic situations have made the degree of uncertainty of China’s economic policies rise continuously.The increasing degree of policy uncertainty will inevitably affect the investment and financing decisions of micro enterprises.Then,how does economic policy uncertainty(EPU)affect mergers and acquisitions(M&A)behavior?What’s the mechanism?Based on the above questions,this paper uses the data of non-financial listed companies in the Shanghai and Shenzhen stock exchanges from 2008 to 2018 as a sample to explore the relationship between EPU and M&A.The study shows that rising EPU will promote corporate M&A behavior,and this effect is more significant in slow-growth companies.The relationship between EPU and M&A is affected by corporate governance,stock price volatility and financing constraints.Specifically,the company’s M&A size is more sensitive to EPU with higher level of corporate governance,higher level of stock price volatility,and lesser financing constraints.Further research shows that the rise of EPU will significantly promote the improvement of M&A performance in the short-term,but this effect does not exist in the long-term.Various robustness checks do not change the empirical results of this paper. 展开更多
关键词 Economic Policy Uncertainly Corporate merger and acquisition Financing constraints M&A performance
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黑盒优化算法在化学合成条件调优中的应用 被引量:1
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作者 陈柯辛 杨耀东 +3 位作者 王博文 郝建业 陈广勇 王平安 《中国科学:化学》 CAS CSCD 北大核心 2023年第1期26-38,共13页
随着自动化实验平台技术的发展,自优化技术与条件调优已成为化学合成的一大趋势.自优化技术通过评估、调整各种反应条件参数来优化反应目标函数,如产率.在自优化技术与算法中,黑盒优化算法有着重要的地位,被广泛地应用于合成化学中的反... 随着自动化实验平台技术的发展,自优化技术与条件调优已成为化学合成的一大趋势.自优化技术通过评估、调整各种反应条件参数来优化反应目标函数,如产率.在自优化技术与算法中,黑盒优化算法有着重要的地位,被广泛地应用于合成化学中的反应条件调优.本文概述了黑盒优化算法在反应条件调优中的应用方式,系统地介绍了化学反应的多种状态表征方式、各类别黑盒优化算法的基本原理以及现有的公开数据集与服务. 展开更多
关键词 黑盒优化 化学合成 反应条件 贝叶斯优化
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立足基础 面向应用 构筑热电科学与技术创新链——“热电材料与器件”重点项目群结题综述
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作者 谭业强 席丽丽 +5 位作者 张文清 唐新峰 陈立东 张清杰 陈克新 苗鸿雁 《中国科学基金》 CSCD 北大核心 2023年第4期640-647,共8页
国家自然科学基金重点项目群“热电材料和器件的基础研究”历时5年(2017年1月至2021年12月)完成。该重点项目群针对热电材料电、热输运协同调控关键科学问题,开展热电材料的微观结构设计、可控制备、器件设计集成等研究,在多元强弱化学... 国家自然科学基金重点项目群“热电材料和器件的基础研究”历时5年(2017年1月至2021年12月)完成。该重点项目群针对热电材料电、热输运协同调控关键科学问题,开展热电材料的微观结构设计、可控制备、器件设计集成等研究,在多元强弱化学键及亚晶格结构热电材料、电热输运理论、多场耦合可控制备、级联器件设计集成等方面取得了一系列创新成果。本文主要综述该重点项目群的统筹和立项背景、科学问题、组织实施过程、重要创新成果、总体完成情况等,并展望了热电材料科学与应用技术的未来发展趋势。 展开更多
关键词 重点项目群 热电材料 结构设计 可控制备 器件设计集成
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