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Polycyclic aromatic hydrocarbon in urban soil from Beijing, China

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Journal of Environmental Sciences 2006年第5期18卷 944-950页

作者： LI Xing-hong MA Ling-ling liu xiu-fen FU Shan CHENG Hang-xin XU Xiao-bai State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Institute of Geophysical and Geochemical Exploration Langfang 065000 China

Polycyclic aromatic hydrocarbons （EPA-PAHs） in the urban surface soils from Beijing were determined using gas chromatography and mass spectrometry （GC-MS）. It is significantly complementary for understanding the PAHs pollution in soil of integrated Beijing city on the basis of the information known in the outskirts. The total concentration of 16 EPA-PAH was from 0.467 to 5.470 μg/g and was described by the contour map. Compound profiles presented that the 4-, 5- and 6-ring PAHs were major compositions. The correlation analysis showed that PAHs have the similar source in the most sampling sites and BaP might be considered as the indicator of PAHs. Characteristic ratios of anthracene （An）/（An＋ phenanthrene （Phe））, fluoranthene （Flu）/（Flu/ pyrene （Pyr）） and benzo[a]pyrene （BaP）/laenzo[g,h,i]perylene （BghiP） indicated that the PAHs pollutants probably mainly originated from the coal combustion and it was not negligible from vehicular emission. The level of PAHs in our study area was compared with other studies.

关键词： PAHs urban soil source Beijing

The coupling control of biological precursors and environmental factors onβ-carotane enrichment in alkaline lacustrine source rocks:A case study from the fengcheng formation in the western Junggar Basin,NW China

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Petroleum Science 2024年第2期21卷 836-854页

作者： Mao-Guo Hou Ming Zha Hua liu Hai-Lei liu Jiang-xiu Qu Ablimit Imin xiu-Jian Ding Zhong-Fa Jiang School of Geosciences China University of PetroleumQingdaoShandong266580China Research Institute of Exploration and Development Xinjiang Petroleum Administration BureauKaramayXinjiang834000China

The organic-rich mudstones and dolostones of the Permian fengcheng Formation(Fm.)are typically alkaline lacustrine source rocks,which are typified by impressively abundantβ-*** β-carotane has been well acknowledged as an effective indicator of biological sources or depositional ***,the specific biological sources of β-carotane and the coupling control of biological sources and environmental factors on the enrichment of β-carotane in the fengcheng *** *** on a comprehensive investigation of the bulk,molecular geochemistry,and organic petrology of sedimentary rocks and the biochemistry of phytoplankton in modern alkaline lakes,we proposed a new understanding of the biological precursors of β-carotane and elucidated the enrichment mechanism of β-carotane in the fengcheng *** results show that the biological precursors crucially control the enrichment of β-carotane in the fengcheng *** haloalkaliphilic cyanobacteria are the primary biological sources of β-carotane,which is suggested by a good positive correlation between the 2-methylhopane index,7-+8-methyl heptadecanes/C_(max),C_(29%),and β-carotane/C_(max)in sedimentary rocks and the predominance of cyanobacteria with abundantβ-carotene in modern alkaline *** enrichment of β-carotane requires the reducing condition,and the paleoredox state that affects the enrichment of β-carotane appears to have a *** paleoclimate conditions do not considerably impact the enrichment of β-carotane,but they have some influence on the water's paleosalinity by affecting evaporation and *** it does not directly affect the enrichment of β-carotane in the fengcheng Fm.,paleosalinity does have an impact on the cyanobacterial precursor supply and the preservation conditions.

关键词： β-carotane enrichment Cyanobacterial input Environmental impact Alkaline lacustrine source rocks The fengcheng formation

Defect spinel oxides for electrocatalytic reduction reactions

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Nano Research 2024年第5期17卷 3547-3570页

作者： Zhijuan liu Jinyu Guo Lu-yu liu fen Wang Zhijie Kong Yanyong Wang Henan Key Laboratory of Crystalline Molecular Functional Materials Henan International Joint Laboratory of Tumor Theranostical Cluster MaterialsKey Laboratory of Special Environmental Functional Materials(Zhengzhou University)Ministry of EducationGreen Catalysis Centerand College of ChemistryZhengzhou UniversityZhengzhou 450001China State Key Laboratory of Chem/Bio-sensing and Chemometrics College of Chemistry and Chemical EngineeringHunan UniversityChangsha 410082China

Electrocatalytic reduction reactions play a crucial role in electrochemical energy conversion and storage technology,which are emerging technologies to ameliorate environmental *** oxides are widely explored in electrocatalytic oxidation reactions but have a poor intrinsic ability to reduction reactions,making their electrocatalytic ability less *** improve this,defect engineering is a valuable method for regulating the electronic structure and coordination ***,this manuscript discusses the use of defect spinel oxides in electrocatalytic reduction reactions,including the different types of defects,construction methods,and characterization *** also outlines the various applications of defect spinel oxides in different electrocatalytic reduction ***,it goes over the challenges and future outlooks for defect *** review aims to thoroughly explain how defect spinels work in electrocatalytic reduction reactions and serve as a helpful guide for creating effective electrocatalysts.

关键词： defect spinel oxides electrochemical reduction reactions electrocatalytic mechanism dynamic evolution

Relationship Between Short-chain Fatty Acids and Parkinson’s Disease:A Review from Pathology to Clinic

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Neuroscience Bulletin 2024年第4期40卷 500-516页

作者： Wen-Xiang Duan fen Wang Jun-Yi liu Chun-feng liu Department of Neurology and Clinical Research Center of Neurological Disease The Second Affiliated Hospital of Soochow UniversitySuzhou215004China Department of Neurology Dushu Lake Hospital affiliated to Soochow UniversitySuzhou215125China Jiangsu Key Laboratory of Neuropsychiatric Diseases and Institute of Neuroscience Soochow UniversitySuzhou215123China

Parkinson’s disease(PD)is a complicated neurodegenerative disease,characterized by the accumulation ofα-synuclein(α-syn)in Lewy bodies and neurites,and massive loss of midbrain dopamine *** evidence suggests that gut microbiota and microbial metabolites are involved in the development of *** these,short-chain fatty acids(SCFAs),the most abundant microbial metabolites,have been proven to play a key role in brain-gut *** this review,we analyze the role of SCFAs in the pathology of PD from multiple dimensions and summarize the alterations of SCFAs in PD patients as well as their correlation with motor and non-motor *** research should focus on further elucidating the role of SCFAs in neuroinflammation,as well as developing novel strategies employing SCFAs and their derivatives to treat PD.

关键词： Parkinson’s disease Short-chain fatty acids Microbial metabolites Brain-gut-microbiota axis

Experimental Investigation on Vertical Hydraulic Transport of Ores in Deepsea Mining

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China Ocean Engineering 2024年第1期38卷 42-53页

作者： liu Lei liu Jian-cheng LI Xin XU Li-xin ZHANG xiu-zhan State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China School of Naval Architecture Ocean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China Sanya Yazhou Bay Institution of Deep-sea Sci-Tech Shanghai Jiao Tong UniversitySanya 572000China China Merchants Marine And Offshore Research Institute Co. Ltd.Shenzhen 518067China China Merchants Deepsea Research Institute(Sanya)Co. Ltd.Sanya 572000China School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China

Deepsea mining has been proposed since the 1960s to alleviate the lack of resources on *** hydraulic transport of collected ores from the seabed to the sea surface is considered the most promising method for industrial *** the present study,an indoor model test of the vertical hydraulic transport of particles was conducted.A noncontact optical method has been proposed to measure the local characteristics of the particles inside a vertical pipe,including the local concentration and particle *** hydraulic gradient of ore transport was evaluated with various particle size distributions,particle densities,feeding concentrations and mixture flow *** transport,the local concentration is larger than the feeding concentration,whereas the particle velocity is less than the mixture *** qualitative effects of the local concentration and local fluid velocity on the particle velocity and slip velocity were *** local fluid velocity contributes significantly to particle velocity and slip velocity,whereas the effect of the local concentration is marginal.A higher feeding concentration and mixture flow velocity result in an increased hydraulic *** effect of the particle size gradation is slight,whereas the particle density plays a crucial role in the transport.

关键词： deepsea mining vertical hydraulic transport experiment flow characteristics

Journal of Genetics and Genomics in 2023:progresses and beyond

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Journal of Genetics and Genomics 2024年第1期51卷 1-2页

作者： xiu-fen Song Xiaoxuan Guo Jing Zhao Yutian Zhang Yuan Qin Jianru Zuo Journal of Genetics and Genomics Institute of Genetics and Developmental BiologyChinese Academy of Sciences&the Genetics Society of ChinaBeijing 100101China

Journal of Genetics and Genomics(JGG),launched in 1974,celebrates its 50th birthday in *** continuous support from our authors,reviewers,readers,and the editorial board,JGG has made remarkable progress in the past year by publishing 122 papers covering major disciplines in life sciences and medical genetics with exciting *** is worthwhile to note that we have recruited 66 young talents to join JGG as junior editors,resulting in significant improvement in manuscript evaluation and journal ***,we summarize major progresses reported in JGG in 2023 fromaneditorial view.

关键词： journal beyond promotion

Preoperative prediction of lymphovascular and perineural invasion in gastric cancer using spectral computed tomography imaging and machine learning

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World Journal of Gastroenterology 2024年第6期30卷 542-555页

作者： Hui-Ting Ge Jian-Wu Chen Li-Li Wang Tian-xiu Zou Bin Zheng Yuan-fen liu Yun-Jing Xue Wei-Wen Lin Department of Radiology Fujian Medical University Union HospitalFuzhou 350001Fujian ProvinceChina Fujian Key Laboratory of Intelligent Imaging and Precision Radiotherapy for Tumors Fujian Medical UniversityFuzhou 350001Fujian ProvinceChina Digestive Hematological and Breast MalignanciesClinical Research Center for Radiology and Radiotherapy of Fujian ProvinceFuzhou 350001Fujian ProvinceChina Department of Radiation Oncology Fujian Medical University Union HospitalFuzhou 350001Fujian ProvinceChina Department of Diagnostic Radiology Fujian Medical University Union HospitalFuzhou 350001Fujian ProvinceChina School of Electrical and Computer Engineering University of OklahomaOklahomaOK 73019United States

BACKGROUND Lymphovascular invasion(LVI)and perineural invasion(PNI)are important prognostic factors for gastric cancer(GC)that indicate an increased risk of metastasis and poor *** preoperative prediction of LVI/PNI status could help clinicians identify high-risk patients and guide treatment ***,prior models using conventional computed tomography(CT)images to predict LVI or PNI separately have had limited *** CT provides quantitative enhancement parameters that may better capture tumor *** hypothesized that a predictive model combining clinical and spectral CT parameters would accurately preoperatively predict LVI/PNI status in GC *** To develop and test a machine learning model that fuses spectral CT parameters and clinical indicators to predict LVI/PNI status *** This study used a retrospective dataset involving 257 GC patients(training cohort,n=172;validation cohort,n=85).First,several clinical indicators,including serum tumor markers,CT-TN stages and CT-detected extramural vein invasion(CT-EMVI),were extracted,as were quantitative spectral CT parameters from the delineated tumor ***,a two-step feature selection approach using correlation-based methods and information gain ranking inside a 10-fold cross-validation loop was utilized to select informative clinical and spectral CT parameters.A logistic regression(LR)-based nomogram model was subsequently constructed to predict LVI/PNI status,and its performance was evaluated using the area under the receiver operating characteristic curve(AUC).RESULTS In both the training and validation cohorts,CT T3-4 stage,CT-N positive status,and CT-EMVI positive status are more prevalent in the LVI/PNI-positive group and these differences are statistically significant(P<0.05).LR analysis of the training group showed preoperative CT-T stage,CT-EMVI,single-energy CT values of 70 keV of venous phase(VP-70 keV),and the ratio of standardized iodine co

关键词： Spectral computed tomography Gastric cancer Lymphovascular invasion Perineural invasion

DLF-YOLOF:an improved YOLOF-based surface defect detection for steel plate

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Journal of Iron and Steel Research International 2024年第2期31卷 442-451页

作者： Guang-hu liu Mao-xiang Chu Rong-fen Gong Ze-hao Zheng School of Electronic and Information Engineering University of Science and Technology LiaoningAnshan114051LiaoningChina

Surface defects can affect the quality of steel *** methods based on computer vision are currently applied to surface defect detection of steel ***,their real-time performance and object detection of small defect are still *** improved object detection network based on You Only Look One-level Feature(YOLOF)is proposed to show excellent performance in surface defect detection of steel plate,called ***,the anchor-free detector is used to reduce the network ***,deformable convolution network and local spatial attention module are introduced into the feature extraction network to increase the contextual information in the feature ***,the soft non-maximum suppression is used to improve detection accuracy ***,data augmentation is performed for small defect objects during training to improve detection *** show the average precision and average precision for small objects are 42.7%and 33.5%at a detection speed of 62 frames per second on a single GPU,*** shows that DLF-YOLOF has excellent performance to meet the needs of industrial real-time detection.

关键词： Steel surface defects detection YOLOF Anchor-free detector Small object detection Real-time detection

A unified Minorization-Maximization approach for estimation of general mixture models

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Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 343-362页

作者： HUANG Xi-fen liu Deng-ge ZHOU Yun-peng ZHU Fei School of Mathematics Yunnan Normal UniversityKunming 650092China Department of Statistics and Actuarial Science The University of Hong KongHong KongChina

The mixed distribution model is often used to extract information from heteroge-neous data and perform modeling *** the density function of mixed distribution is complicated or the variable dimension is high,it usually brings challenges to the parameter es-timation of the mixed distribution *** application of MM algorithm can avoid complex expectation calculations,and can also solve the problem of high-dimensional optimization by decomposing the objective *** this paper,MM algorithm is applied to the parameter estimation problem of mixed distribution *** method of assembly and decomposition is used to construct the substitute function with separable parameters,which avoids the problems of complex expectation calculations and the inversion of high-dimensional matrices.

关键词： MM algorithm mixed distribution model parameter estimation assembly decomposition tech-nology parameter separation