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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 *** this study,the concept of the existence state of asphaltenes was introduced to semi-quantitatively investigate the precipitation and aggregation characteristics of *** 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 *** 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 *** 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 *** stem cell(MSC)transplantation is used to reduce tissue damage,but exosomes are more stable and highly conserved than *** 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 ***:Primary hippocampal neurons obtained from 18-day Sprague-Dawley rat embryos were subjected to OGD/R treatment,with or without MSC-Exo *** integration,cell viability,mitochondrial membrane potential,and generation of reactive oxygen species(ROS)were *** deoxynucleotidyl transferase-mediated 2’-deoxyuridine 5’-triphosphate nickend labeling(TUNEL)staining was performed to detect neuronal ***,mitochondrial function-associated gene expression,Nrf2 translocation,and expression of downstream antioxidant proteins were ***: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 *** abovementioned changes were partially reversed by exosomal treatment of the hippocampal ***:MSC-Exo treatment can alleviate OGD/R-induced oxidative stress and dysregulation of mitochondrial function-associated genes in hippocampal ***,MSCExo might be a potential therapeutic strategy to preven

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

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Diffuse invasive signet ring cell carcinoma in total colorectum caused by ulcerative colitis:A case report and review of literature

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World Journal of Clinical Cases 2022年第5期10卷 1729-1737页

作者： Zhi Zhang peng-fei yu Guo-Li Gu yu-Hui Zhang yu-Ming Wang Zhi-Wei Dong Hai-Rui Yang Department of General Surgery Air Force Medical CenterChinese People's Liberation ArmyBeijing 100142China Graduate School Hebei North UniversityZhangjiakou 075000Hebei ProvinceChina Health Team 93656 Troop of Chinese People's Liberation ArmyBeijing 101113China

BACKGROUND Diffuse invasive signet ring cell carcinoma of the colorectum is extremely rare *** type of colorectal cancer has certain clinical,pathological and biological characteristics that are different from ordinary colorectal *** SUMMARY A 31-year-old young woman was admitted to the hospital for nearly 1 wk due to recurrent symptoms of mucopurulent bloody stools and abdominal *** colonoscopy showed a ring-shaped intestinal wall mass 10 cm from the rectum to the *** pieces of tumor tissue were removed for *** pathological results showed rectal mucinous *** patient underwent laparoscopic exploration under general anesthesia,and then laparoscopic total colorectal resection,ileal pouch–anal anastomosis and ileostomy were *** patient was switched to a FOLFOX+cetuximab *** the fifth cycle,the patient was unable to tolerate further treatment due to tumor progression and multiple organ dysfunction,and died at the end of May *** survival was 7 *** Carcinogenesis of ulcerative colitis is different from sporadic colon cancer,and the overall prognosis is extremely poor.

关键词： Ulcerative colitis Colorectal cancer Signet ring cell carcinoma Case report

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Investigation on synergistic deposition of wax and hydrates in waxy water-in-oil(W/O) flow systems

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Petroleum Science 2022年第4期19卷 1840-1852页

作者： Yang Liu Xiao-Fang Lv Qian-Li Ma Shi-Dong Zhou Bo-Hui Shi Hui Du yun Lei peng-fei yu Shang-fei Song Jing Gong Bing-Cai Sun Jiangsu Key Laboratory of Oil and Gas Storage and Transportation Technology Changzhou UniversityChangzhouJiangsu213164China Institute of Petroleum Engineering Technology Sinopec Northwest Oil Field CompanyUrumqiXinjiang830011China National Engineering Laboratory for Pipeline Safety/State Key Laboratory of Natural Gas Hydrate China University of Petroleum-BeijingBeijing102249China CNPC Safety and Environmental Protection Technology Research Institute Co.Ltd Beijing102206China

Elucidating the synergistic effect of wax and hydrates, involving formation, aggregation and deposition,is imperative to the operation and transportation safety for offshore petroleum fields. To understand the characteristics and mechanism of synergistic deposition of wax and hydrates, flow and deposition experiments of systems with different wax contents(0-2.89 wt%), initial flow rates, pressures and temperatures were conducted in a high pressure visual flow loop. According to the flow rate and pressure drop data as well as the visual window observation, four different types of plugging scenarios of waxhydrate coexisting systems with different flow properties and wall deposition state were summarized,including rapid plugging, transition plugging, gradual plugging type I and gradual plugging type *** with the wax-free system after hydrate formation, even with the addition of anti-agglomerant(AA) with the same concentration, wax-hydrate coexisting systems could not reach stable hydrate slurry flow state, indicating that the existence of wax deteriorated the performance of AA. Aside from the influence of wax crystals on hydrate agglomeration, it was found that wax deposition layer would alter the adhesion and bedding of hydrates, resulting in the variation of flow properties and wall deposition *** low wax content systems(0.75 wt%) where rapid plugging occurred, the synergistic effect between wax and hydrates promoted the formation of wax-hydrate coupling aggregates, resulting in severe local deposition when the coupling aggregates attained critical deposition size and consequently decreasing flow rate, forming a vicious circle of decreasing transportability. Since bedding of coupling aggregates was hindered by the uniformly coated wax deposition layer on pipe wall, gradual plugging rather than rapid plugging occurred in medium wax content systems(1-1.25 wt%), predominately caused by the gradual increment in viscosity of waxy hydrate slurry. For relative

关键词： Flow assurance Wax Hydrates Flow properties Synergistic deposition

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Predictive value of preoperative routine examination for the prognosis of patients with pT2N0M0 or pT3N0M0 colorectal cancer

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World Journal of Gastrointestinal Oncology 2024年第6期16卷 2429-2438页

作者： peng-fei Jing Jin Chen En-Da yu Chao-yu Miao Department of Colorectal Surgery Changhai HospitalSecond Military Medical University/Naval Medical UniversityShanghai 200433China Department of Endocrinology and Metabolism Changhai HospitalSecond Military Medical University/Naval Medical UniversityShanghai 200433China Department of Pharmacology Second Military Medical University/Naval Medical UniversityShanghai 200433China

BACKGROUND In recent years,the incidence of colorectal cancer(CRC)has been *** the popularization of endoscopic technology,a number of early CRC has been ***,despite current treatment methods,some patients with early CRC still experience postoperative recurrence and *** To search for indicators associated with early CRC recurrence and metastasis to identify high-risk *** A total of 513 patients with pT2N0M0 or pT3N0M0 CRC were retrospectively enrolled in this *** of blood routine test,liver and kidney function tests and tumor markers were collected before *** were followed up through disease-specific database and telephone *** recurrence,metastasis or death were used as the end point of study to find the risk factors and predictive value related to early CRC recurrence and *** We comprehensively compared the predictive value of preoperative blood routine,blood biochemistry and tumor markers for disease-free survival(DFS)and overall survival(OS)of *** multivariate analysis demonstrated that low platelet count was significantly associated with poor DFS[hazard ratio(HR)=0.995,95% confidence interval(CI):0.991-0.999,P=0.015],while serum carcinoembryonic antigen(CEA)level(HR=1.008,95%CI:1.001-1.016,P=0.027)and serum total cholesterol level(HR=1.538,95%CI:1.026-2.305,P=0.037)were independent risk factors for *** cutoff value of serum CEA level for predicting OS was 2.74 ng/*** the OS of CRC patients with serum CEA higher than the cutoff value was worse than those with lower CEA level,the difference between the two groups was not statistically significant(P=0.075).CONCLUSION For patients with T2N0M0 or T3N0M0 CRC,preoperative platelet count was a protective factor for DFS,while serum CEA level was an independent risk factor for *** that these measures are easier to detect and more acceptable to patients,they may have broader applications.

关键词： Colorectal cancer Platelet count Serum carcinoembryonic antigen Total cholesterol level Overall survival Disease-free survival

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Fast charge transfer kinetics in Sv-ZnIn_(2)S_(4)/Sb_(2)S_(3)S-scheme heterojunction photocatalyst for enhanced photocatalytic hydrogen evolution

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Rare Metals 2024年第2期43卷 533-542页

作者： Wei Li Jia-Jun Li Zhi-fei Liu Hong-yu Ma peng-fei Fang Rui Xiong Jian-Hong Wei Key Laboratory of Artificial Micro-and Nano-Structures of Ministry of Education School of Physics and TechnologyWuhan UniversityWuhan430072China

Constructing a S-scheme heterojunction with tight interface contact and fast charge transfer is beneficial to improving the photocatalytic hydrogen evolution ***,a unique one-dimensional(1D)/two-dimensional(2D)S-scheme heterojunction containing 1D Sb_(2)S_(3) nanorods and 2D ZnIn_(2)S_(4) with affluent sulfur vacancies(denoted as Sv-ZnIn_(2)S_(4)@Sb_(2)S_(3)) was *** introduced sulfur vacancy can promote the effective adsorption of H+for the following interfacial hydrogen-evolution ***,the larger contact area and stronger electron interaction between Sb_(2)S_(3) and ZnIn_(2)S_(4) effectively inhibits the recombination of photo-generated electron–hole pairs and abridges the migration distance of *** a result,the optimal Sv-ZnIn_(2)S_(4)@Sb_(2)S_(3) sample achieves H_(2) evolution activity of 2741.3 mol·h^(−1)·g^(−1),which is 8.6 times that of pristine ZnIn_(2)S_(4) and 3.0 times that of the Sv-ZnIn_(2)S_(4) *** on the experimental result,the photo-reactivity S-scheme mechanism of hydrogen evolution from water splitting with Sv-ZnIn_(2)S_(4)@Sb_(2)S_(3) is *** work provides an effective method for developing S-scheme heterojunction composites of transition metal sulfide with high hydrogen evolution performance.

关键词： ZnIn_(2)S_(4) nanosheets S-scheme heterojunction Sulfur vacancy Charge transfer and separation Photocatalytic H_(2)evolution

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Potential seismic landslide hazard and engineering effect in the Ya’an-Linzhi section of the Sichuan-Tibet transportation corridor, China

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China Geology 2023年第2期6卷 228-240页

作者： Zhi-hua Yang Chang-bao Guo Rui-an Wu Wei-wei Shao peng-fei yu Cai-hong Li Institute of Geomechanics Chinese Academy of Geological SciencesBeijing 100081China Key Laboratory of Active Tectonics and Geological Safety Ministry of Natural ResourcesBeijing 100081China State Key Laboratory of Resources and Environmental Information System Beijing 100101China China University of Geosciences Wuhan 430074China China University of Geosciences(Beijing) Beijing 100083China

The Sichuan-Tibet transportation corridor is located at the eastern margin of the Qinghai-Tibet Plateau,where the complex topography and geological conditions,developed geo-hazards have severely restricted the planning and construction of major *** the long-term prevention and early control of regional seismic landslides,based on analyzing seismic landslide characteristics,the Newmark model was used to carry out the potential seismic landslide hazard assessment with a 50-year beyond probability 10%.The results show that the high seismic landslide hazard is mainly distributed along large active tectonic belts and deep-cut river canyons,and are significantly affected by the active *** low seismic landslide hazard is mainly distributed in the flat terrain such as the Quaternary basins,broad river valleys,and plateau planation *** major east-west linear projects mainly pass through five areas with high seismic landslide hazard:Luding-Kangding section,Yajiang-Xinlong(Yalong river)section,Batang-Baiyu(Jinsha river)section,Basu(Nujiang river)section,and Bomi-Linzhi(eastern Himalaya syntaxis)*** seismic action of the Bomi-Linzhi section can also induce high-risk geo-hazard chains such as the high-level glacial lake breaks and glacial debris *** early prevention of seismic landslides should be strengthened in the areas with high seismic landslide hazard.

关键词： Qinghai-Tibet Plateau Sichuan-Tibet transportation corridor Seismic landslide Hazard assessment Engineering effect

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Peutz-Jeghers syndrome without STK11 mutation may correlate with less severe clinical manifestations in Chinese patients

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World Journal of Gastroenterology 2023年第21期29卷 3302-3317页

作者： Li-Xin Jiang yu-Rui Chen Zu-Xin Xu yu-Hui Zhang Zhi Zhang peng-fei yu Zhi-Wei Dong Hai-Rui Yang Guo-Li Gu Air Force Clinical College of China Medical University Beijing 100142China Fifth Clinical College(Air Force Clinical College)of Anhui Medical University Beijing 100142China Department of General Surgery Air Force Medical CenterChinese People's Liberation ArmyFifth Clinical(Air Force Clinical College)of China Medical UniversityBeijing 100142China

BACKGROUND Peutz-Jeghers syndrome(PJS) is an autosomal dominant genetic disease with skin mucosal pigment spots and gastrointestinal(GI) multiple hamartoma polyps as clinical characteristics. At present, it is considered that the germline mutation of STK11 gene is the genetic cause of PJS. However, not all PJS patients can be detected STK11 germline mutations. The specific clinical characteristics of these PJS patients without STK11 mutation is an interesting clinical question. Or, like wild type GI stromal tumor, whether these PJS without STK11 mutation are also called PJS is worth discussing. Therefore, we designed the study to understand the clinical characteristics of these PJS patients without STK11 *** To investigates whether PJS patients with known STK11 mutations have a more severe spectrum of clinical phenotypes compared to those *** A total of 92 patients with PJS admitted to the Air Force Medical Center from 2010 to 2022 were randomly selected for study. Genomic DNA samples were extracted from peripheral blood samples, and pathogenic germline mutations of STK11 were detected by high-throughput next-generation gene sequencing. Clinicalpathologic manifestations of patients with and without STK11/LKB1 mutations were *** STK11 germline mutations were observed in 73 patients with PJS. Among 19 patients with no detectable STK11 mutations, six had no pathogenic germline mutations of other genes, while 13 had other genetic mutations. Compared with PJS patients with STK11 mutations, those without tended to be older at the age of initial treatment, age of first intussusception and age of initial surgery. They also had a lower number of total hospitalizations relating to intussusception or intestinal obstruction, and a lower load of small intestine *** PJS patients without STK11 mutations might have less severe clinical-pathologic manifestations than those with.

关键词： Peutz-Jeghers syndrome STK11 Mutant type Wild type

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Clinical features,diagnosis,and treatment of Peutz-Jeghers syndrome:Experience with 566 Chinese cases

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World Journal of Gastroenterology 2023年第10期29卷 1627-1637页

作者： Zu-Xin Xu Li-Xin Jiang yu-Rui Chen yu-Hui Zhang Zhi Zhang peng-fei yu Zhi-Wei Dong Hai-Rui Yang Guo-Li Gu Fifth Clinical College of Anhui Medical University Air Force Clinical College of Anhui Medical UniversityBeijing 100142China Air Force Clinical College of China Medical University Beijing 100142China Department of General Surgery Air Force Medical CenterChinese People's Liberation ArmyBeijing 100142China

BACKGROUND Peutz-Jeghers syndrome(PJS)is a clinically rare disease with pigmented spots on the lips and mucous membranes and extremities,scattered gastrointestinal polyps,and susceptibility to tumors as clinical *** preventive and curative methods are still *** we summarize our experience with 566 Chinese patients with PJS from a Chinese medical center with regard to the clinical features,diagnosis,and *** To explore the clinical features,diagnosis,and treatment of PJS in a Chinese medical *** The diagnosis and treatment information of 566 cases of PJS admitted to the Air Force Medical Center from January 1994 to October 2022 was summarized.A clinical database was established covering age,gender,ethnicity,family history,age at first treatment,time and sequence of appearance of mucocutaneous pigmentation,polyp distribution,quantity,and diameter,frequency of hospitalization,fre-quency of surgical operations,*** clinical data was retrospectively analyzed using SPSS 26.0 software,with P<0.05 considered statistically *** Of all the patients included,55.3%were male and 44.7%were *** time to the appearance of mucocutaneous pigmentation was 2 years,and median time from the appearance of mucocutaneous pigmentation to the occurrence of abdominal symptoms was 10 *** vast majority(92.2%)of patients underwent small bowel endoscopy and treatment,with 2.3%having serious *** was a statistically significant difference in the number of enteroscopies between patients with and without canceration(P=0.004,Z=-2.882);71.2%of patients underwent surgical operation,75.6%of patients underwent surgical operation before the age of 35 years,and there was a statistically significant difference in the frequency of surgical operations between patients with and without cancer(P=0.000,Z=-5.127).At 40 years of age,the cumulative risk of intussusception in PJS was approximately 72.0%,and at 50 years,t

关键词： Peutz-Jeghers syndrome Management Intussusception Canceration STK11

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Coupling of RANS and BEM Solvers for Simulation of Propeller Behind the Hull in Full Appended Model

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China Ocean Engineering 2024年第3期38卷 424-438页

作者： Saeed NAJAFI Mehdi POURMOSTAFA LIU peng-fei Iranian National Institute for Oceanography and Atmospheric Science(INIOAS) Tehran 14155-4781Iran Department of Maritime Engineering Amir Kabir University of TechnologyTehran 15875-4413Iran Marine Offshore and Subsea TechnologySchool of EngineeringNewcastle UniversityNewcastle upon TyneNE17RUUK

To design a propeller for ship power plant,the interaction between ship hull and propeller must be taken into *** main concern is to apply the wake effect of ship stern on the propeller *** this paper,a coupled BEM(Boundary Element Method)/RANS(Renolds-Averaged Navier−Stokes)solver is used to simulate propeller behind the hull in the self-propulsion *** motivation of this work is to develop a practical tool to design marine propulsion system without suffering long computational *** unsteady boundary element method which is also known as panel method is chosen to estimate the propeller *** wakes are treated using a time marching wake alignment ***,a RANS code coupled with VoF equation is developed to consider the ship motions and wake field effects in the problem.A coupling algorithm is developed to interchange ship wake field to the potential flow solver and propeller thrust to the RANS *** on the difference between hull resistance and the propeller thrust,a PI controller is developed to compute the propeller RPM in every time *** of the solver is carried out using the towing tank test report of a 50 m oceanography research *** factor and trust deduction coefficient are estimated ***,the wake rollup pattern of the propeller in open water is compared with the propeller in real wake field.

关键词： RANS BEM coupled method ship propeller self-propulsion wake sheet pattern

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