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Prediction model on hydrolysis kinetics of phthalate monoester:A density functional theory study

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Journal of Environmental Sciences 2024年第1期135卷 51-58页

作者： Tong xu Jingwen Chen Deming Xia Weihao Tang Jiansheng Cui chun Liu Shuangjiang Li College of Environmental Science and Engineering Hebei University of Science and TechnologyShijiazhuang 050000China Key Laboratory of Industrial Ecology and Environmental Engineering(Ministry of Education) School of Environmental Science and TechnologyDalian University of TechnologyDalian 116024China National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and ManagementInstitute of Eco-environmental and Soil SciencesGuangdong Academy of SciencesGuangzhou 510650China

As primary degradation products of phthalate esters,phthalate monoesters(MPEs)have been widely detected in various aquatic environments and drawn growing toxicological *** kinetics that is of importance for assessing environmental persistence of chemicals remain elusive for ***,kinetics of base-catalyzed and neutral hydrolysis for 18 MPEs with different leaving groups was investigated by density functional theory *** indicate that MPEs with leaving groups having p Kaof<10 prefer dissociative transition *** are more persistent than their parents,and their hydrolysis half-lives were calculated to vary from 3.4 min to 79.2 years(p H=7–9).A quantitative structure-activity relationship model was developed for predicting the hydrolysis kinetics *** was found that p Kaof the leaving groups and electronegativity of the MPEs are key factors determining the hydrolysis *** work may lay a theoretical foundation for better understanding the chemical process that governs MPE persistence in aquatic environments.

关键词： Phthalate monoesters Phthalate esters Hydrolysis Density functional theory Quantitative structure-activity relationship

Hemichorea in patients with temporal lobe infarcts: Two case reports

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World Journal of Clinical Cases 2024年第4期12卷 806-813页

作者： xu-Dong Wang Xing Li chun-Lian Pan Department of Neurology Puren Hospital Affiliated to Wuhan University of Science and TechnologyWuhan 430081Hubei ProvinceChina School of Medicine Wuhan University of Science and TechnologyWuhan 430065Hubei ProvinceChina

BACKGROUND Hemichorea and other hyperkinetic movement disorders are uncommon present-ations of stroke and are usually secondary to deep infarctions affecting the basal ganglia and ***,temporal ischemic lesions causing hemichorea are *** report the cases of two patients with acute ischemic temporal lobe infarct strokes that presented as *** SUMMARY Patient 1:An 82-year-old woman presented with a 1-mo history of involuntary movement of the left extremity,which was consistent with *** diffusion-weighted imaging(DWI)revealed an acute ischemic stroke that predominantly affected the right temporal cortex,and magnetic resonance angiography of the head showed significant stenosis of the right middle cerebral artery(MCA).Treatment with 2.5 mg of olanzapine per day was *** she was discharged from the hospital,her symptoms appeared to have improved compared with those previously ***-seven days after the first admission,she was readmitted due to acute ischemic *** tomogra-phy perfusion showed marked hypoperfusion in the right MCA *** emergency transfemoral cerebral angiogram was performed and showed severe stenosis in the M1 segment of the right *** percutaneous transluminal angioplasty was successfully performed,abnormal movements or other neuro-logic problems did not *** 2:A 76-year-old man was admitted to our hospital for a 7-d history of right-upper-sided involuntary *** showed an acute patchy ischemic stroke in the left temporal lobe without basal ganglia *** diffusion tensor imaging confirmed fewer white matter fiber tracts on the left side than on the opposite *** with 2.5 mg of olanzapine per day improved his condition,and he was *** When acute hemichorea suddenly appears,temporal cortical ischemic stroke should be considered a possible *** addition,hemichorea may be a sign of impending cerebral infarcti

关键词： Acute ischemic stroke Temporal ischemic stroke Movement disorders Cortical hemichorea Case report

Seasonal Characteristics of Forecasting Uncertainties in Surface PM_(2.5)Concentration Associated with Forecast Lead Time over the Beijing-Tianjin-Hebei Region

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Advances in Atmospheric Sciences 2024年第5期41卷 801-816页

作者： Qiuyan DU chun ZHAO Jiawang FENG Zining YANG Jiamin xu Jun GU Mingshuai ZHANG Mingyue xu Shengfu LIN Deep Space Exploration Laboratory/School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China CAS Center for Excellence in Comparative Planetology University of Science and Technology of ChinaHefei 230026China

Forecasting uncertainties among meteorological fields have long been recognized as the main limitation on the accuracy and predictability of air quality ***,the particular impact of meteorological forecasting uncertainties on air quality forecasts specific to different seasons is still not well *** this study,a series of forecasts with different forecast lead times for January,April,July,and October of 2018 are conducted over the Beijing-Tianjin-Hebei(BTH)region and the impacts of meteorological forecasting uncertainties on surface PM_(2.5)concentration forecasts with each lead time are *** increased lead time,the forecasted PM_(2.5)concentrations significantly change and demonstrate obvious seasonal *** general,the forecasting uncertainties in monthly mean surface PM_(2.5)concentrations in the BTH region due to lead time are the largest(80%)in spring,followed by autumn(~50%),summer(~40%),and winter(20%).In winter,the forecasting uncertainties in total surface PM_(2.5)mass due to lead time are mainly due to the uncertainties in PBL heights and hence the PBL mixing of anthropogenic primary *** spring,the forecasting uncertainties are mainly from the impacts of lead time on lower-tropospheric northwesterly winds,thereby further enhancing the condensation production of anthropogenic secondary particles by the long-range transport of natural *** summer,the forecasting uncertainties result mainly from the decrease in dry and wet deposition rates,which are associated with the reduction of near-surface wind speed and precipitation *** autumn,the forecasting uncertainties arise mainly from the change in the transport of remote natural dust and anthropogenic particles,which is associated with changes in the large-scale circulation.

关键词： PM_(2.5) forecasting uncertainties forecast lead time meteorological fields Beijing-Tianjin-Hebei region

Catalytic asymmetric dearomative azo-Diels–Alder reaction of 2-vinlyindoles

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Chinese Chemical Letters 2024年第4期35卷 357-362页

作者： Yu-Hang Miao Zheng-xu Zhang xu-Yi Huang Yuan-Zhao Hua Shi-Kun Jia Xiao Xiao Min-Can Wang Li-Ping xu guang-Jian Mei Green Catalysis Center and College of ChemistryZhengzhou UniversityZhengzhou 450052China School of Chemistry and Chemical Engineering Shandong University of TechnologyZibo 255000China Institute of Pharmaceutical Science and Technology Zhejiang University of TechnologyHangzhou 310014China

Due to the high electrophilic nature of azo-dienophiles, azo-Diels–Alder proceeds rapidly even without the need of a catalyst and is therefore regarded as the “click reaction”. This spontaneity causes strong background reaction and poses a daunting challenge to chemists for developing the catalytic asymmetric version. Reported herein is the first catalytic asymmetric dearomative azo-Diels–Alder reaction between2-vinylindoles and triazoledione. This protocol makes use of the high energy barrier of dearomatization to avert the strong background reaction of azo-Diels–Alder reaction, allowing the implementation of the projected reaction at ambient temperature. Density functional theory calculations have been performed to gain insights into the reaction mechanism and the origins of the enantioselectivity. By using this method,a variety of tetracyclic indole derivatives have been readily prepared in good to excellent yields and with excellent diastereo-and enantio–selectivities(33 examples, up to 97% yield and >99% ee, >20:1 dr).

关键词： Catalytic asymmetric dearomatization Azo-Diels–Alder reaction 2-Vinylindoles Chiral phosphoric acid Tetracyclic indole derivatives

Precipitating thermally reinforcement phase in aluminum alloys for enhanced strength at 400℃

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Journal of Materials Science & Technology 2024年第5期172卷 71-82页

作者： Xiang Su Yuan Lei Yang Chen Hongjie Qu Zhixiang Qi Gong Zheng xu Liu Henggao Xiang guang Chen National Key Laboratory of Advanced Casting Technologies MIIT Key Laboratory of Advanced Metallic and Intermetallic Materials TechnologyEngineering Research Center of Materials Behavior and DesignMinistry of EducationNanjing University of Science and TechnologyNanjing 210094China School of Aviation and Mechanical Engineering Changzhou Institute of TechnologyChangzhou 213032China

Heat-resistant aluminum alloys are widely used in aerospace and automotive fields for manufacturing hot components due to their advantages in lightweight design and energy ***,the high-temperature strength of existing cast aluminum alloys is always limited to about 100 MPa at 350℃due to coarsening and transformation of strengthening ***,we reveal that the yield strength and ultimate tensile strength of the T6 state Al-8.4Cu-2.3Ce-1.0Mn-0.5Ni-0.2Zr alloy at 400◦C increase by 34%and 44%after re-aging at 300℃for 100 h,and its thermal strength exhibits distinguished ad-vantage over traditional heat-resistant aluminum *** enhanced elevated-temperature strength is attributed to the reprecipitation of the Ni-bearing T-Al_(20)Cu_(2)Mn_(3)phase,whose number density increases over one *** significant segregation of Ni,Ce,and Zr elements at the interfaces helps improve the thermal stability of the T *** thermostable T phase effectively strengthens the matrix by in-hibiting dislocation ***,a highly interconnected 3D intermetallic network along the grain boundaries can still remain after long-term re-aging at 300℃,which is conducive to imposing a drag on the grain boundaries at high *** finding offers a viable route for enhancing the elevated-temperature strength of heat-resistant aluminum alloys,which could provide expanded opportunities for higher-temperature applications.

关键词： Aluminum alloys Precipitation Thermally reinforcement phase Re-aging treatment High-temperature strength

On Some Discrete Bonnesen-style Isoperimetric Inequalities

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Acta Mathematica Sinica,English Series 2024年

作者： chun Na ZENG xu DONG College of Mathematics Science Chongqing Normal University

This article deals with the sharp discrete isoperimetric inequalities in analysis and geometry for planar convex polygons. First, the analytic isoperimetric inequalities based on the Schur convex function are established. In the wake of the analytic isoperimetric inequalities, Bonnesen-style isoperimetric inequalities and inverse Bonnesen-style inequalities for the planar convex polygons are obtained.

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Failure behavior and strength model of blocky rock mass with and without rockbolts

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International Journal of Mining Science and Technology 2024年第6期34卷 747-762页

作者： chun Zhu Xiansen Xing Manchao He Zhicheng Tang Feng Xiong Zuyang Ye Chaoshui xu School of Earth Sciences and Engineering Hohai UniversityNanjing 210024China Key Laboratory of Water Management and Water Security for Yellow River Basin Ministry of Water Resources(under construction)Zhengzhou 450003China State Key Laboratory for Geomechanics&Deep Underground Engineering China University of Mining and TechnologyBeijing 10083China Faculty of Engineering China University of GeosciencesWuhan 430074China State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan 430071China School of Resource and Environmental Engineering Wuhan University of Science and TechnologyWuhan 430081China School of Chemical Engineering Faculty of SciencesEngineering and TechnologyThe University of AdelaideAdeliade 5005Australia

To better understand the failure behaviours and strength of bolt-reinforced blocky rocks,large scale extensive laboratory experiments are carried out on blocky rock-like specimens with and without rockbolt *** results show that both shear failure and tensile failure along joint surfaces are observed but the shear failure is a main controlling factor for the peak strength of the rock mass with and without *** rockbolts are necked and shear deformation simultaneously happens in bolt reinforced rock *** the joint dip angle increases,the joint shear failure becomes more *** number of rockbolts has a significant impact on the peak strain and uniaxial compressive strength(UCS),but little influence on the deformation modulus of the rock *** the Winkler beam model to represent the rockbolt behaviours,an analytical model for the prediction of the strength of boltreinforced blocky rocks is *** agreement between the UCS values predicted by proposed model and obtained from experiments suggest an encouraging performance of the proposed *** addition,the performance of the proposed model is further assessed using published results in the literature,indicating the proposed model can be used effectively in the prediction of UCS of bolt-reinforced blocky rocks.

关键词： Blocky rock mass Rockbolt ground support Uniaxial compression test Failure mechanism Uniaxial compressive strength model

MiRNA-145-5p inhibits gastric cancer progression via the serpin family E member 1-extracellular signal-regulated kinase-1/2 axis

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 2123-2140页

作者： Hong-Xia Bai xue-Mei Qiu chun-Hong xu Jian-Qiang Guo Department of Gastroenterology The Second Hospital of Shandong UniversityJinan 250000Shandong ProvinceChina Department of Gastroenterology Liaocheng People’s HospitalLiaocheng 252000Shandong ProvinceChina Department of Reproductive Center Zaozhuang Maternal and Child Health Care HospitalZaozhuang 277000Shandong ProvinceChina

BACKGROUND MicroRNAs(miRNAs)regulate gene expression and play a critical role in cancer ***,there is still a limited understanding of the function and regulatory mechanism of miRNAs in gastric cancer(GC).AIM To investigate the role and molecular mechanism of miRNA-145-5p(miR145-5p)in the progression of *** Real-time polymerase chain reaction(RT-PCR)was used to detect miRNA expression in human GC tissues and *** ability of cancer cells to migrate and invade was assessed using wound-healing and transwell assays,*** proliferation was measured using cell counting kit-8 and colony formation assays,and apoptosis was evaluated using flow *** of the epithelial-mesenchymal transition(EMT)-associated protein was determined by Western *** of miR-145-5p were predicated using bioinformatics analysis and verified using a dual-luciferase reporter *** family E member 1(SERPINE1)expression in GC tissues and cells was evaluated using RT-PCR and immunohistochemical *** correlation between SERPINE1 expression and overall patient survival was determined using Kaplan-Meier plot *** association between SERPINE1 and GC progression was also tested.A rescue experiment of SERPINE1 overexpression was conducted to verify the relationship between this protein and *** mechanism by which miR-145-5p influences GC progression was further explored by assessing tumor formation in nude *** GC tissues and cells had reduced miR-145-5p expression and SERPINE1 was identified as a direct target of this *** of miR-145-5p was associated with decreased GC cell proliferation,invasion,migration,and EMT,and these effects were reversed by forcing SERPINE1 ***-Meier plot analysis revealed that patients with higher SERPINE1 expression had a shorter survival rate than those with lower SERPINE1 *** mouse tumorigenesis experiments confirmed that miR-145-5p target

关键词： Gastric cancer MicroRNA-145-5p Serpin family E member 1 Epithelial-mesenchymal transition Proliferation Extracellular signal-regulated kinase-1/2

Identification of male schizophrenia patients using brain morphology based on machine learning algorithms

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World Journal of Psychiatry 2024年第6期14卷 804-811页

作者： Tao Yu Wen-Zhi Pei chun-Yuan xu Chen-Chen Deng xu-Lai Zhang Department of Clinical Nutrition Hefei Fourth People’s HospitalHefei 230032Anhui ProvinceChina Department of Psychiatry Hefei Fourth People’s HospitalHefei 230032Anhui ProvinceChina Department of Gynaecology Anhui Maternal and Child Health HospitalHefei 230032Anhui ProvinceChina

BACKGROUND Schizophrenia is a severe psychiatric disease,and its prevalence is ***,diagnosis of early-stage schizophrenia is still considered a challenging *** To employ brain morphological features and machine learning method to differentiate male individuals with schizophrenia from healthy *** The least absolute shrinkage and selection operator and t tests were applied to select important features from structural magnetic resonance images as input features for *** commonly used machine learning algorithms,the general linear model,random forest(RF),k-nearest neighbors,and support vector machine algorithms,were used to develop the classification *** performance of the classification models was evaluated according to the area under the receiver operating characteristic curve(AUC).RESULTS A total of 8 important features with significant differences between groups were considered as input features for the establishment of classification models based on the four machine learning *** to other machine learning algorithms,RF yielded better performance in the discrimination of male schizophrenic individuals from healthy controls,with an AUC of *** Our research suggests that brain morphological features can be used to improve the early diagnosis of schizophrenia in male patients.

关键词： Schizophrenia Machine learning Classification Structure Magnetic Resonance imaging