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Time-domain dynamic constitutive model suitable for mucky soil site seismic response

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Earthquake Engineering and Engineering Vibration 2024年第1期23卷 1-13页

作者： Dong qing Chen su Jin Liguo Zhou Zhenghua Li Xiaojun Architectural Engineering Institute Huaiyin Institute of TechnologyHuai’an 223600China Key Laboratory of Urban Security and Disaster Engineering of Ministry of Education Beijing University of TechnologyBeijing 100020China Institute of Geophysics China Earthquake AdministrationBeijing 100089China College of Transportation Science and Engineering Nanjing Tech UniversityNanjing 211816China

Soil nonlinear behavior displays noticeable effects on the site seismic response.This study proposes a new functional expression of the skeleton curve to replace the hyperbolic skeleton curve.By integrating shear modulus and combining the dynamic skeleton curve and the damping degradation coefficient,the constitutive equation of the logarithmic dynamic skeleton can be obtained,which considers the damping effect in a soil dynamics problem.Based on the finite difference method and the multi-transmitting boundary condition,a 1D site seismic response analysis program called Soilresp1D has been developed herein and used to analyze the time-domain seismic response in three types of sites.At the same time,this study also provides numerical simulation results based on the hyperbolic constitutive model and the equivalent linear method.The results verify the rationality of the new soil dynamic constitutive model.It can analyze the mucky soil site nonlinear seismic response,reflecting the deformation characteristics and damping effect of the silty soil.The hysteresis loop area is more extensive,and the residual strain is evident.

关键词： seismic response time-domain dynamic constitutive model logarithmic dynamic skeleton dampening effect mucky soil

Fabricating functionally graded Fe-Cr-Co permanent magnetic alloys via laser powder bed fusion

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Journal of Iron and Steel Research(International) 2024年第3期31卷 729-737页

作者： Ya-zhou He Ya-qing Hou Peng Shen Hao Zhang Dong Zhou Hang su Central Iron and Steel Research Institute Co. Ltd.Beijing 100081China Material Digital R&D Center China Iron and Steel Research Institute Group Co.Ltd.Beijing 100081China

Laser powder bed fusion(LPBF)in-situ alloying technology offers the possibility to construct gradient materials with varied structures and properties.Functionally graded Fe-Cr-Co permanent magnetic alloys were fabricated by LPBF and in-situ alloying mixed powders of Fe,Cr,and Co elements.The effects of different Fe,Cr and Co contents on the microstructure,magnetic properties and hardness of Fe-Cr-Co alloys prepared by LPBF were studied.The as-built Fe-Cr-Co alloys present a single body-centered-cubic phase and have a homogeneous distribution of elements.The mechanical properties and magnetic properties of the compositionally graded sample show a gradient variation.With the increase in Cr content,the Vickers hardness of the sample increases,and the saturation magnetization of the sample decreases.The optimal magnetic properties in an isotropic state are given as coercivity HcB=21.65 kA/m,remanence Br=0.70 T and energy product(BH)_(max)=5.35 kJ/m^(3),which are comparable to or higher than the reported magnetic properties in an isotropic state prepared by traditional powder metallurgy.LPBF in-situ alloying technology has the potential to further explore Fe-Cr-Co magnetic materials,such as those consisting of multiple or more constituent elements,and to maximize the compositional flexibility of magnetic materials.

关键词： Fe-Cr-Co alloy Laser powder bed fusion In-situ alloying Functional material Magnetic property

P-and SV-wave dispersion and attenuation in saturated microcracked porous rock with aligned penny-shaped fractures

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Petroleum Science 2024年第1期21卷 143-161页

作者： Sheng-qing Li Wen-Hao Wang Yuan-Da su Jun-Xin Guo Xiao-Ming Tang School of Geosciences China University of Petroleum(East China)Qingdao 266580ShandongChina Laoshan National Laboratory Qingdao 266071ShangdongChina Guangdong Provincial Key Laboratory of Geophysical High-resolution Imaging Technology Southern University of Science and TechnologyShenzhen 518055GuangdongChina Department of Earth and Space Sciences Southern University of Science and TechnologyShenzhen 518055GuangdongChina

P-and SV-wave dispersion and attenuation have been extensively investigated in saturated poroelastic media with aligned fractures.However,there are few existing models that incorporate the multiple wave attenuation mechanisms from the microscopic scale to the macroscopic scale.Hence,in this work,we developed a unified model to incorporate the wave attenuation mechanisms at different scales,which includes the microscopic squirt flow between the microcracks and pores,the mesoscopic wave-induced fluid flow between fractures and background(FB-WIFF),and the macroscopic Biot's global flow and elastic scattering(ES)from the fractures.Using Tang's modified Biot's theory and the mixed-boundary conditions,we derived the exact frequency-dependent solutions of the scattering problem for a single penny-shaped fracture with oblique incident P-and SV-waves.We then developed theoretical models for a set of aligned fractures and randomly oriented fractures using the Foldy approximation.The results indicated that microcrack squirt flow considerably influences the dispersion and attenuation of P-and SV-wave velocities.The coupling effects of microcrack squirt flow with the FB-WIFF and ES of fractures cause much higher velocity dispersion and attenuation for P waves than for SV waves.Randomly oriented fractures substantially reduce the attenuation caused by the FB-WIFF and ES,particularly for the ES attenuation of SV waves.Through a comparison with existing models in the limiting cases and previous experimental measurements,we validated our model.

关键词： Aligned fractures P-and SV-wave Dispersion and attenuation Microcracked porous background FB-WIFF Elastic scattering Squirt flow

Cumulative effects of excess high-normal alanine aminotransferase levels in relation to new-onset metabolic dysfunction-associated fatty liver disease in China

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World Journal of Gastroenterology 2024年第10期30卷 1346-1357页

作者： Jing-Feng Chen Zhuo-qing Wu Hao-Shuang Liu su Yan You-Xiang Wang Miao Xing Xiao-Qin Song su-Ying Ding Health Management Center The First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052Henan ProvinceChina Institute of Systems Engineering Dalian University of TechnologyDalian 116024Liaoning ProvinceChina College of Public Health Zhengzhou UniversityZhengzhou 450001Henan ProvinceChina School of Basic Medicine and Forensic Medicine Henan University of Science and TechnologyLuoyang 471003Henan ProvinceChina

BACKGROUND Within the normal range,elevated alanine aminotransferase(ALT)levels are associated with an increased risk of metabolic dysfunction-associated fatty liver disease(MAFLD).AIM To investigate the associations between repeated high-normal ALT measurements and the risk of new-onset MAFLD prospectively.METHODS A cohort of 3553 participants followed for four consecutive health examinations over 4 years was selected.The incidence rate,cumulative times,and equally and unequally weighted cumulative effects of excess high-normal ALT levels(ehALT)were measured.Cox proportional hazards regression was used to analyse the association between the cumulative effects of ehALT and the risk of new-onset MAFLD.REsuLTS A total of 83.13%of participants with MAFLD had normal ALT levels.The incidence rate of MAFLD showed a linear increasing trend in the cumulative ehALT group.Compared with those in the low-normal ALT group,the multivariate adjusted hazard ratios of the equally and unequally weighted cumulative effects of ehALT were 1.651[95%confidence interval(CI):1.199-2.273]and 1.535(95%CI:1.119-2.106)in the third quartile and 1.616(95%CI:1.162-2.246)and 1.580(95%CI:1.155-2.162)in the fourth quartile,respectively.CONCLUSION Most participants with MAFLD had normal ALT levels.Long-term high-normal ALT levels were associated with a cumulative increased risk of new-onset MAFLD.

关键词： Metabolic dysfunction-associated fatty liver disease High-normal alanine aminotransferase level Cumulative effect Cox proportional hazards regression Cohort study

Prospects in the application of ultrasensitive chromosomal aneuploidy detection in precancerous lesions of gastric cancer

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World Journal of Gastrointestinal surgery 2024年第1期16卷 6-12页

作者： su-Ting Qian Fei-Fei Xie Hao-Yu Zhao qing-Sheng Liu Dan-Li Cai Department of Digestive Hangzhou Hospital of Traditional Chinese MedicineHangzhou 310007Zhejiang ProvinceChina Science and Education Section Hangzhou Hospital of Traditional Chinese MedicineHangzhou 310007Zhejiang ProvinceChina Intensive Care Unit The First Affiliated Hospital of Zhejiang Chinese Medical UniversityHangzhou 311122Zhejiang ProvinceChina

Gastric cancer(GC)is a prevalent malignant tumor within the digestive system,with over 40%of new cases and deaths related to GC globally occurring in China.Despite advancements in treatment modalities,such as surgery supplemented by adjuvant radiotherapy or chemotherapeutic agents,the prognosis for GC remains poor.New targeted therapies and immunotherapies are currently under invest-igation,but no significant breakthroughs have been achieved.Studies have indicated that GC is a heterogeneous disease,encompassing multiple subtypes with distinct biological characteristics and roles.Consequently,personalized treatment based on clinical features,pathologic typing,and molecular typing is crucial for the diagnosis and management of precancerous lesions of gastric cancer(PLGC).Current research has categorized GC into four subtypes:Epstein-Barr virus-positive,microsatellite instability,genome stability,and chromosome instability(CIN).Technologies such as multi-omics analysis and gene sequencing are being employed to identify more suitable novel testing methods in these areas.Among these,ultrasensitive chromosomal aneuploidy detection(UCAD)can detect CIN at a genome-wide level in subjects using low-depth whole genome sequencing technology,in conjunction with bioinformatics analysis,to achieve qualitative and quantitative detection of chromosomal stability.This editorial reviews recent research advancements in UCAD technology for the diagnosis and management of PLGC.

关键词： Gastric cancer Precancerous lesions of gastric cancer Molecular typing Ultrasensitive chromosomal aneuploidy detection Adjuvant therapy Application prospects

Design of weak current measurement system and research on temperature impact

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Nuclear Science and Techniques 2024年第4期35卷 46-56页

作者： Chu-Xiang Zhao San-Gang Li Rong-Rong su Li Yang Ming-Zhe Liu qing-Yue Xue Shan Liao Zhi Zhou qing-Shan Tan Xian-Guo Tuo Yi Cheng College of Nuclear Technology and Automation Engineering Chengdu University of Technology1#DongsanluErxianqiaoChengdu 610059China Applied Nuclear Technology in Geosciences Key Laboratory of Sichuan Province Chengdu University of Technology1#DongsanluErxianqiaoChengdu 610059China University of Science and Technology of China Hefei 230026China School of Physics and Electronic Engineering Sichuan University of Science and EngineeringZigong 643000China

A dedicated weak current measurement system was designed to measure the weak currents generated by the neutron ionization chamber.This system incorporates a second-order low-pass filter circuit and the Kalman filtering algorithm to effectively filter out noise and minimize interference in the measurement results.Testing conducted under normal temperature conditions has demonstrated the system's high precision performance.However,it was observed that temperature variations can affect the measurement performance.Data were collected across temperatures ranging from -20 to 70℃,and a temperature correction model was established through linear regression fitting to address this issue.The feasibility of the temperature correction model was confirmed at temperatures of -5 and 40℃,where relative errors remained below 0.1% after applying the temperature correction.The research indicates that the designed measurement system exhibits excellent temperature adaptability and high precision,making it particularly suitable for measuring weak currents.

关键词： Weak current measurement system Neutron ionization chamber Kalman filter algorithm Temperature correction model

Associations of sleeping patterns and isotemporal substitution of other behavior with the prevalence of CKD in Chinese adults

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Frontiers of Medicine 2024年第2期18卷 303-314页

作者： Yi Ding Xiaoli Xu Zhuojun Xin Qiuyu Cao Jiaojiao Huang Xianglin Wu Yanan Huo Qin Wan Yingfen Qin Ruying Hu Lixin Shi qing su Xuefeng Yu Li Yan Guijun Qin Xulei Tang Gang Chen Min Xu Tiange Wang Zhiyun Zhao Zhengnan Gao Guixia Wang Feixia Shen Zuojie Luo Li Chen Qiang Li Zhen Ye Yinfei Zhang Chao Liu Youmin Wang Tao Yang Huacong Deng Lulu Chen Tianshu Zeng Jiajun Zhao Yiming Mu Shengli Wu Yuhong Chen Jieli Lu Weiqing Wang Guang Ning Yu Xu Yufang Bi Mian Li Department of Endocrine and Metabolic Diseases Shanghai Institute of Endocrine and Metabolic DiseasesRuijin HospitalShanghai Jiao Tong University School of MedicineShanghai200025China Shanghai National Clinical Research Center for Metabolic Diseases Key Laboratory for Endocrine and Metabolic Diseases of the National Health Commission of ChinaShanghai Key Laboratory for Endocrine TumorState Key Laboratory of Medical GenomicsRuijin HospitalShanghai Jiao Tong University School of MedicineShanghai200025China Jiangxi Provincial People’s Hospital Affiliated to Nanchang UniversityNanchang330000China Department of Endocrinology The Affiliated Hospital of Southwest Medical UniversityLuzhou646000China Department of Endocrinology The First Affiliated Hospital of Guangxi Medical UniversityNanning530000China Zhejiang Provincial Center for Disease Control and Prevention Hangzhou310000China Department of Endocrinology Affiliated Hospital of Guiyang Medical UniversityGuiyang550000China Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of MedicineShanghai200000China Tongji Hospital Tongji Medical CollegeHuazhong University of Science and TechnologyWuhan430000China sun Yat-sen Memorial Hospital Sun Yat-sen UniversityGuangzhou510000China Department of Endocrinology The First Affiliated Hospital of Zhengzhou UniversityZhengzhou450000China Department of Endocrinology The First Hospital of Lanzhou UniversityLanzhou730000China Fujian Provincial Hospital Fujian Medical UniversityFuzhou350000China Dalian Municipal Central Hospital Affiliated of Dalian Medical UniversityDalian116000China Department of Endocrinology The First Hospital of Jilin UniversityChangchun130000China Department of Endocrinology The First Affiliated Hospital of Wenzhou Medical UniversityWenzhou325000China Qilu Hospital of Shandong University Jinan250000China Department of Endocrinology The Second Affiliated Hospital of Harbin Medical UniversityHarbin150000China Department of Endocrinology Cen

Studies have found a U-shaped relationship between sleep duration and chronic kidney disease(CKD)risk,but limited research evaluated the association of reallocating excessive sleep to other behavior with CKD.We included 104538 participants from the nationwide cohort of the Risk Evaluation of Cancers in Chinese Diabetic Individuals:A Longitudinal Study,with self-reported time of daily-life behavior.Using isotemporal substitution models,we found that substituting 1 h of sleeping with sitting,walking,or moderate-to-vigorous physical activity was associated with a lower CKD prevalence.Leisure-time physical activity displacement was associated with a greater prevalence reduction than occupational physical activity in working population.In stratified analysis,a lower CKD prevalence related to substitution toward physical activity was found in long sleepers.More pronounced correlations were observed in long sleepers with diabetes than in those with prediabetes,and they benefited from other behavior substitutions toward a more active way.The U-shaped association between sleep duration and CKD prevalence implied the potential effects of insufficient and excessive sleep on the kidneys,in which the pernicious link with oversleep could be reversed by time reallocation to physical activity.The divergence in the predicted effect on CKD following time reallocation to behavior of different domains and intensities and in subpopulations with diverse metabolic statuses underlined the importance of optimizing sleeping patterns and adjusting integral behavioral composition.

关键词： sleep physical activity chronic kidney disease isotemporal substitution behavioral pattern

Acid-rock reaction kinetics in a two-scale model based on reaction order correction

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Petroleum Science 2024年第3期21卷 2089-2101页

作者： Xue-Song Li Ning Qi Ze-Hui Zhang Lian Liu Xia-qing Li Xu-Hang su School of Petroleum Engineering China University of Petroleum(East China) Key Lab of Unconventional Oil & Gas Development Ministry of Education China University of Petroleum(East China) SINOPEC Northwest Oilfield Branch Company Petroleum Engineering Technology Research Institute SINOPEC Shengli Oilfield Company

The reaction order plays a crucial role in evaluating the response rate of acid-rock. However, the conventional two-scale model typically assumes that the reaction order is constant as one, which can lead to significant deviations from reality. To address this issue, this study proposes a novel multi-order dynamic model for acid-rock reaction by combining rotating disk experimental data with theoretical derivation.Through numerical simulations, this model allows for the investigation of the impact of acidification conditions on different orders of reaction, thereby providing valuable insights for on-site construction.The analysis reveals that higher response orders require higher optimal acid liquid flow rates, and lower optimal H+diffusion coefficients, and demonstrate no significant correlation with acid concentration.Consequently, it is recommended to increase the displacement and use high-viscosity acid for reservoirs with high calcite content, while reducing the displacement and using low-viscosity acid for reservoirs with high dolomite content.

关键词： Reaction order Two-scale model Wormhole propagation Carbonate rocks Numerical simulation

Plasma metabolites and risk of myocardial infarction:a bidirectional Mendelian randomization study

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Journal of Geriatric Cardiology 2024年第2期21卷 219-231页

作者： Dong-Hua LI Qiang WU Jing-Sheng LAN Shuo CHEN You-Yi HUANG Lan-Jin WU Zhi-qing QIN Ying HUANG Wan-Zhong HUANG Ting ZENG Xin HAO Hua-Bin su Qiang su Department of Cardiovascular Medicine Minzu Hospital of Guangxi Zhuang Autonomous RegionGuangxiChina Senior Department of Cardiology the Sixth Medical CenterChinese PLA General HospitalBeijingChina Library of Graduate School Chinese PLA General HospitalBeijingChina Department of Cardiology Jiangbin Hospital of Guangxi Zhuang Autonomous RegionGuangxiChina Health Management Institute the Second Medical CenterChinese PLA General HospitalBeijingChina

BACKGROUND Myocardial infarction(MI)is a critical cardiovascular event with multifaceted etiology,involving several genetic and environmental factors.It is essential to understand the function of plasma metabolites in the development of MI and unravel its complex pathogenesis.METHODS This study employed a bidirectional Mendelian randomization(MR)approach to investigate the causal relationships between plasma metabolites and MI risk.We used genetic instruments as proxies for plasma metabolites and MI and conducted MR analyses in both directions to assess the impact of metabolites on MI risk and vice versa.In addition,the large-scale genome-wide association studies datasets was used to identify genetic variants associated with plasma metabolite(1400 metabolites)and MI(20,917 individuals with MI and 440,906 individuals without MI)susceptibility.Inverse variance weighted was the primary method for estimating causal effects.MR estimates are expressed as beta coefficients or odds ratio(OR)with 95%CI.REsuLTS We identified 14 plasma metabolites associated with the occurrence of MI(P<0.05),among which 8 plasma metabolites[propionylglycine levels(OR=0.922,95%CI:0.881–0.965,P<0.001),gamma-glutamylglycine levels(OR=0.903,95%CI:0.861–0.948,P<0.001),hexadecanedioate(C16-DC)levels(OR=0.941,95%CI:0.911–0.973,P<0.001),pentose acid levels(OR=0.923,95%CI:0.877–0.972,P=0.002),X-24546 levels(OR=0.936,95%CI:0.902–0.971,P<0.001),glycine levels(OR=0.936,95%CI:0.909–0.964,P<0.001),glycine to serine ratio(OR=0.930,95%CI:0.888–0.974,P=0.002),and mannose to trans-4-hydroxyproline ratio(OR=0.912,95%CI:0.869–0.958,P<0.001)]were correlated with a decreased risk of MI,whereas the remaining 6 plasma metabolites[1-palmitoyl-2-arachidonoyl-GPE(16:0/20:4)levels(OR=1.051,95%CI:1.018–1.084,P=0.002),behenoyl dihydrosphingomyelin(d18:0/22:0)levels(OR=1.076,95%CI:1.027–1.128,P=0.002),1-stearoyl-2-docosahexaenoyl-GPE(18:0/22:6)levels(OR=1.067,95%CI:1.027–1.109,P=0.001),alpha-ketobutyrate levels(OR=1.108,95%CI:1.041–1.180,P=0.001),5-acetylamino-6-formylam

关键词： infarction alterations diagnosis