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Effect of existence state of asphaltenes on the asphaltenes-wax interaction in wax deposition

Petroleum Science 2023年第1期20卷 507-514页

作者： yun Lei Han Wang Shuang-Shuang Li Xue-Qian Liu Hao-Ran Zhu yu-Ming Gao Hao-Ping peng Peng-Fei Yu Jiangsu Key Laboratory of Oil and Gas Storage&Transportation Technology Changzhou UniversityJiangsu213164China

Asphaltenes are the most elusive substances in waxy crude oil,especially the complex structures,which leads to significant precipitation and aggregation characteristics of asphaltenes,and affects the asphaltenes-wax interaction.In this study,the concept of the existence state of asphaltenes was introduced to semi-quantitatively investigate the precipitation and aggregation characteristics of asphaltenes.On this basis,the influence of the existence state of asphaltenes on wax deposition was studied by coldfinger device and high-temperature gas chromatography,and the composition and properties of the deposits were analyzed.Four main findings were made:(1)As the asphaltene concentration increases,the existence state of asphaltenes gradually transitions from dispersed state to aggregated state,and the asphaltene concentration of 0.30 wt%in this study is the starting point of the transition.(2)The existence state of asphaltenes in crude oil does affect the process of wax deposition,as shown in the fact that the dispersed asphaltenes promote the occurrence of wax deposition,while the aggregated asphaltenes can inhibit wax deposition.(3)In the presence of the aggregated asphaltenes,that is,when the asphaltene concentration is higher than 0.30 wt%,the shedding phenomenon of deposit layer was observed,and with the increase of aggregated asphaltenes,the deposit layer fell off earlier.(4)With the increase of the dispersed asphaltenes,the wax appearance temperature(WAT)and wax content of the deposits all showed an increasing trend,while with the appearance of the aggregated asphaltenes,the above situation was reversed.The findings of this study can help for better understanding of the interaction between the asphaltenes and wax in wax deposition.

关键词： Asphaltenes Precipitation/aggregation Existence state of asphaltenes Deposition

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Protective effect of mesenchymal stem cell-derived exosomal treatment of hippocampal neurons against oxygen-glucose deprivation/reperfusion-induced injury

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World Journal of Emergency Medicine 2022年第1期13卷 46-53页

作者： Xiao-fang Guo Shuang-shuang Gu Jun Wang Hao Sun yu-juan Zhang Peng-Fei Yu Jin-song Zhang Lei Jiang Department of Emergency the First Affi liated Hospital of Nanjing Medical UniversityNanjing 210029China Key Laboratory of Modern Toxicology Ministry of EducationDepartment of ToxicologySchool of Public HealthNanjing Medical UniversityNanjing 211166China Key Laboratory of Modern Toxicology Ministry of EducationDepartment of Environmental GenomicsSchool of Public HealthNanjing Medical UniversityNanjing 211166China Center for Drug Safety Evaluation and Research Shanghai Institute of Materia MedicaShanghai 201203China

BACKGROUND:Individuals who survive a cardiac arrest often sustain cognitive impairments due to ischemia-reperfusion injury.Mesenchymal stem cell(MSC)transplantation is used to reduce tissue damage,but exosomes are more stable and highly conserved than MSCs.This study was conducted to investigate the therapeutic effects of MSC-derived exosomes(MSC-Exo)on cerebral ischemia-reperfusion injury in an in vitro model of oxygen-glucose deprivation/reperfusion(OGD/R),and to explore the underlying mechanisms.METHODS:Primary hippocampal neurons obtained from 18-day Sprague-Dawley rat embryos were subjected to OGD/R treatment,with or without MSC-Exo treatment.Exosomal integration,cell viability,mitochondrial membrane potential,and generation of reactive oxygen species(ROS)were examined.Terminal deoxynucleotidyl transferase-mediated 2’-deoxyuridine 5’-triphosphate nickend labeling(TUNEL)staining was performed to detect neuronal apoptosis.Moreover,mitochondrial function-associated gene expression,Nrf2 translocation,and expression of downstream antioxidant proteins were determined.RESULTS:MSC-Exo attenuated OGD/R-induced neuronal apoptosis and decreased ROS generation(P<0.05).The exosomes reduced OGD/R-induced Nrf2 translocation into the nucleus(2.14±0.65 vs.5.48±1.09,P<0.01)and increased the intracellular expression of antioxidative proteins,including superoxide dismutase and glutathione peroxidase(17.18±0.97 vs.14.40±0.62,and 20.65±2.23 vs.16.44±2.05,respectively;P<0.05 for both).OGD/R significantly impaired the mitochondrial membrane potential and modulated the expression of mitochondrial functionassociated genes,such as PINK,DJ1,LRRK2,Mfn-1,Mfn-2,and OPA1.The abovementioned changes were partially reversed by exosomal treatment of the hippocampal neurons.CONCLUSIONS:MSC-Exo treatment can alleviate OGD/R-induced oxidative stress and dysregulation of mitochondrial function-associated genes in hippocampal neurons.Therefore,MSCExo might be a potential therapeutic strategy to prevent OGD/R-induced neuronal injury.

关键词： Mesenchymal stem cells Exosomes Oxygen-glucose deprivation/reperfusion Reactive oxygen species Mitochondria

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Production of dissolved organic carbon in the South China Sea:A modeling study

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Science China Earth Sciences 2022年第2期65卷 351-364页

作者： Wentao MA peng XIU Yi yu Yiling ZHENG fei CHAI State Key Laboratory of Satellite Ocean Environment Dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519080China Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou) Guangzhou 511458China State Key Laboratory of Tropical Oceanography South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China School of Marine Sciences University of MaineOrono 04469MaineUSA

The South China Sea(SCS)is the largest semi-enclosed marginal sea in the western Pacific.The alternation of East Asian monsoon causes a significant seasonal pattern of chlorophyll,primary productivity,and export flux of sinking particles.However,the source and sink of dissolved organic carbon(DOC)pools with different bioavailability are less studied.Here we evaluated the seasonal production of DOC in labile,semi-labile and refractory forms using a coupled physical-biogeochemical model.This study aims to understand the dynamics and budgets of organic matters in the SCS.Model results show that the production of labile,semi-labile and refractory DOC is highly correlated with the net primary productivity(NPP)which is higher in winter and lower in summer,reflecting a dependence of DOC on the NPP.The seasonal variation in Pearl River discharge dominates the DOC production in the northern coastal region.In the northeast,the Kuroshio intrusion associated frontal system is attributed to cause high winter production.The DOC production in the southwest is controlled by both winter mixing and summer upwelling.The production of refractory DOC with the least bioavailability favors carbon sequestration.Its annual mean production is 1.8±0.5 mg C m^(−2) d^(−1),equivalent to 26%of the export flux of particulate organic carbon at 1000 m.

关键词： Dissolved organic carbon Microbial carbon pump South China Sea Biogeochemical model ROMS CoSiNE

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Mutation analysis of related genes in hamartoma polyp tissue of Peutz-Jeghers syndrome

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World Journal of Gastroenterology 2020年第16期26卷 1926-1937页

作者： Zhi Zhang Fu-Xiao Duan Guo-Li Gu Peng-Fei Yu Air Force Clinical College(Air Force Medical Center)of Anhui Medical University Beijing 100142China Department of General Surgery the General Hospital of Northern Theater Command PLAShenyang 110016Liaoning ProvinceChina Department of General Surgery Air Force Medical CenterPLABeijing 100142China

BACKGROUND Peutz-Jeghers syndrome(PJS)is a rare disease with clinical manifestations of pigmented spots on the lips,mucous membranes and extremities,scattered gastrointestinal polyps,and susceptibility to tumors.The clinical heterogeneity of PJS is obvious,and the relationship between clinical phenotype and genotype is still unclear.AIM To investigate the mutation status of hereditary colorectal tumor-associated genes in hamartoma polyp tissue of PJS patients and discuss its relationship with the clinicopathological data of PJS.METHODS Twenty patients with PJS were randomly selected for this study and were treated in the Air Force Medical Center(former Air Force General Hospital)PLA between 2008 and 2017.Their hamartoma polyp tissues were used for APC,AXIN2,BMPR1A,EPCAM,MLH1,MLH3,MSH2,MSH6,MUTYH,PMS1,PMS2,PTEN,SMAD4,and LKB1/STK11 gene sequencing using next-generation sequencing technology.The correlations between the sequencing results and clinical pathological data of PJS were analyzed.RESULTS Fourteen types of LKB1/STK11 mutations were detected in 16 cases(80.0%),of which 8 new mutations were found(3 types of frameshift deletion mutations:c.243delG,c.363_364delGA,and c.722delC;2 types of frameshift insertions:c.144_145insGCAAG,and c.454_455insC;3 types of splice site mutations:c.464+1G>T,c.464+1G>A,and c.598-1G>A);9 cases(45.0%)were found to have 18 types of heterozygous mutations in the remaining 13 genes except LKB1/STK11.Of these,MSH2:c.792+1G>A,MSH6:c.3689C>G,c.4001+13C>CTTAC,PMS1:c.46C>t,and c.922G>A were new mutations.CONCLUSION The genetic mutations in hamartoma polyp tissue of PJS are complex and diverse.Moreover,other gene mutations in PJS hamartoma polyp tissue were observed,with the exception of LKB1/STK11 gene,especially the DNA mismatch repair gene(MMR).Colorectal hamartoma polyps with LKB1/STK11 mutations were larger in diameter than those with other gene mutations.

关键词： Peutz-Jeghers syndrome STK11 gene LKB1 gene Sequencing Genetic analysis

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Endovascular coiling versus microsurgical clipping for ruptured intracranial aneurysms:a meta-analysis and systematic review

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Chinese Neurosurgical Journal 2022年第4期8卷 268-283页

作者： Chao peng yu-hang Diao Shi-fei Cai Xin-yu Yang Department of Neurosurgery Tianjin Medical University General HospitalTianjinThe People’s Republic of China

Background:The purpose of this analysis is to evaluate the current evidence with regard to the effectiveness and safety between coiling and clipping in patients with ruptured intracranial aneurysms(RIAs).Methods:We performed a meta-analysis that compared clipping with coiling between July 2000 and September 2021.PubMed,EMBASE,and the Cochrane Library were searched for related articles systematically.And the treatment efficacy and postoperative complications were analyzed.Results:We identified three randomized controlled trials and thirty-seven observational studies involving 60,875 patients with ruptured cerebral aneurysms.The summary results showed that coiling was related a better quality of life(mRS0-2;OR=1.327;CI=1.093-1.612;p<0.05),a higher risk of mortality(OR=1.116;CI=1.054-1.180;p<0.05),higher rate of rebleeding(RR=1.410;CI=1.092-1.822;p<0.05),lower incidence of vasospasm(OR=0.787;CI=0.649-0.954;p<0.05),higher risk of hydrocephalous(RR=1.143;CI=1.043-1.252;p<0.05),lower risk of cerebral infarction(RR=0.669;CI=0.596-0.751;p<0.05),lower risk of neuro deficits(RR=0.720;CI=0.582-0.892;p<0.05),and a lower rate of complete occlusion(OR=0.495;CI=0.280-0.876;p<0.05).Conclusion:Coiling was significantly associated with a better life quality(mRS0-2),a lower incidence of postoperative complications,and a higher rate of mortality,rebleeding,hydrocephalous,and a lower rate of complete occlusion than clipping.

关键词： Ruptured intracranial aneurysms Coiling Clipping Meta-analysis

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A hybrid method for product low-end disruptive innovation

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Frontiers of Mechanical Engineering 2022年第3期17卷 159-176页

作者： yu WANG Runhua TAN Qingjin peng Jianguang SUN Haoyu LI fei yu School of Mechanical Engineering Hebei University of TechnologyTianjin300401China National Engineering Research Center for Technological Innovation Method and Tool Hebei University of TechnologyTianjin300401China Department of Mechanical Engineering University of ManitobaWinnipegMBR3T 2N2Canada

Product innovation is often a process for improving existing products.Low-end disruptive innovation(LDI)enables a product to meet the most price-sensitive customers in the low-end market.The existing LDI methods are mainly based on unnecessary characteristics of disruptive innovations.Thus,they cannot easily identify and respond to the LDI design needs.This study proposes a hybrid method for the product LDI in two levels of the product design based on the summarized definition and essential characteristics of LDI.Feasible areas of the product LDI are determined using a hybrid relational function model to identify the maturity of dominant technologies.The technologies are identified through the technical search and evaluation of the feasible area for innovation to form an initial LDI scheme.Then,the product function is optimized using the trimming concept of theory of inventive problem solving based on the characteristics of LDI.The final LDI scheme is formed and evaluated based on the essential characteristics of the product LDI.The feasibility of the proposed method is verified in the design of a new dropping pill machine.

关键词： low-end disruptive innovation product design design improvement theory of inventive problem solving TRIZ trimming

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Frequency-Domain Full-Waveform Inversion Based on Tunnel Space Seismic Data

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Engineering 2022年第11期18卷 197-206页

作者： Mingyu yu fei Cheng Jiangping Liu Daicheng peng Zhijian Tian Hubei Subsurface Multiscale Imaging Key Laboratory(SMIL) Institute of Geophysics and GeomaticsChina University of GeosciencesWuhan 430074China Hubei Key Laboratory of Marine Geological Resources China University of GeosciencesWuhan 430074China

Tunnel seismic detection methods are effective for obtaining the geological structure around the tunnel face,which is critical for safe construction and disaster mitigation in tunnel engineering.However,there is often a lack of accuracy in the acquired geological information and physical properties ahead of the tunnel face in the current tunnel seismic detection methods.Thus,we apply a frequency-domain acoustic full-waveform inversion(FWI)method to obtain high-resolution results for the tunnel structure.We discuss the influence of the frequency group selection strategy and the tunnel observation system settings regarding the inversion results and determine the structural imaging and physical property parameter inversion of abnormal geological bodies ahead of the tunnel face.Based on the conventional strategies of frequency-domain acoustic FWI,we propose a frequency group selection strategy that combines a low-frequency selection covering the vertical wavenumber and a high-frequency selection of antialiasing.This strategy can effectively obtain the spatial structure and physical parameters of the geology ahead of the tunnel face and improve the inversion resolution.In addition,by linearly increasing the side length of the tunnel observation system,we share the influence of the length of the two sides of the observation systems of different tunnels on the inversion results.We found out that the inversion results are the best when the side length is approximately five times the width of the tunnel face,and the influence of increasing the side observation length beyond this range on the inversion results can be ignored.Finally,based on this approach,we invert for the complex multi-stratum model,and an accurate structure and physical property parameters of the complex stratum ahead of the tunnel face are obtained,which verifies the feasibility of the proposed method.

关键词： Tunnel seismic detection Full-waveform inversion Frequency select strategy Observation system

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Establishment of injury models in studies of biological effects induced by microwave radiation

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Military Medical Research 2021年第2期8卷 253-272页

作者： yun-fei Lai Hao-yu Wang Rui-yun peng Beijing Institute of Radiation Medicine Beijing 100850China

Microwave radiation has been widely used in various fields,such as communication,industry,medical treatment,and military applications.Microwave radiation may cause injuries to both the structures and functions of various organs,such as the brain,heart,reproductive organs,and endocrine organs,which endanger human health.Therefore,it is both theoretically and clinically important to conduct studies on the biological effects induced by microwave radiation.The successful establishment of injury models is of great importance to the reliability and reproducibility of these studies.In this article,we review the microwave exposure conditions,subjects used to establish injury models,the methods used for the assessment of the injuries,and the indicators implemented to evaluate the success of injury model establishment in studies on biological effects induced by microwave radiation.

关键词： Microwave radiation Injury model Biological effects Methods Biological indicators Review

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A novel stacking-based ensemble learning model for drilling efficiency prediction in earth-rock excavation

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2022年第12期23卷 1027-1046页

作者： fei LV Jia yu Jun ZHANG peng yu Da-wei TONG Bin-ping WU State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin UniversityTianjin 300350China

Accurate prediction of drilling efficiency is critical for developing the earth-rock excavation schedule.The single machine learning(ML)prediction models usually suffer from problems including parameter sensitivity and overfitting.In addition,the influence of environmental and operational factors is often ignored.In response,a novel stacking-based ensemble learning method taking into account the combined effects of those factors is proposed.Through multiple comparison tests,four models,e Xtreme gradient boosting(XGBoost),random forest(RF),back propagation neural network(BPNN)as the base learners,and support vector regression(SVR)as the meta-learner,are selected for stacking.Furthermore,an improved cuckoo search optimization(ICSO)algorithm is developed for hyper-parameter optimization of the ensemble model.The application to a real-world project demonstrates that the proposed method outperforms the popular single ML method XGBoost and the ensemble model optimized by particle swarm optimization(PSO),with 16.43%and 4.88%improvements of mean absolute percentage error(MAPE),respectively.

关键词： Drilling efficiency Prediction Earth-rock excavation Stacking-based ensemble learning Improved cuckoo search optimization(ICSO)algorithm Comprehensive effects of various factors Hyper-parameter optimization

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Comparison of Clinical Outcome of Autograft and Allograft Reconstruction for Anterior Cruciate Ligament Tears

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中华医学杂志(英文版) 2015年第23期128卷 3163-3166页

作者： Jia yu-Hua Sun peng-fei Shandong 250012 China Qilu Hospital of Shandong University Jinan Department of Orthopedics

Background: Hamstring (HS) autograft and bone-patellar tendon-bone allograft are the most common choice for reconstruction of anterior cruciate ligament (ACL). There was a little report about the clinical outcome and difference of arthroscopic ACL reconstruction using allograft and autograft. This study aimed to compare the clinical outcome of autograft and allograft reconstruction for ACL tears.Methods: A total of 106 patients who underwent surgery because of ACL tear were included in this study. The patients were randomly divided into two groups, including 53 patients in each group. The patients in group I underwent standard ACL reconstruction with HS tendon autografts, while others in group II underwent reconstruction with bone-patellar tendon-bone allograft. All the patients were followed up and analyzed; the mean follow-up was 81 months (range: 28–86 months). Clinical outcomes were evaluated using the International Knee Documentation Committee (IKDC), Lysholm scores, physical instability tests, and patient satisfaction questionnaires. The complication rates of both groups were compared. Tibial and femoral tunnel widening were assessed using lateral and anteroposterior radiographs.Results: At the end of follow-up, no significant differences were found between the groups in terms of IKDC, Lysholm scores, physical instability tests, patient satisfaction questionnaires, and incidences of arthrofibrosis. Tibial and femoral tunnel widening was less in the HS tendon autografts. This difference was more significant on the tibial side.Conclusions: In the repair of ACL tears, allograft reconstruction is as effective as the autograft reconstruction, but the allograft can lead to more tunnel widening evidently in the tibial tunnel, particularly.

关键词： Allograft Anterior Cruciate Ligament Autograft Reconstruction

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