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Numerical investigation on compressible flow around a cylinder in proximity to the heated wall

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Journal of Hydrodynamics 2024年第3期36卷 519-533页

作者： yu-lu liu Jun-wang Qu Yi-zhou Tao Yong-guang Lyu Xiang Qiu Shanghai Institute of Technology School of ScienceShanghai201418China Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai Institute of Applied Mathematics and MechanicsSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai200072China

In this study,direct numerical simulations were conducted to investigate the compressible flow around a circular cylinder near a heated wall at a Reynolds number(Re)of 500 and a Mach number(Ma)of *** heating ratio T^(*)ranging from 1.0 to 1.6 represents the different situations of a heated wall,whereas the gap ratio ranges from 0.3 to *** study analyzed the impact of heating effect and wall proximity on flow characteristics and aerodynamic *** results indicated that the stability of the flow was enhanced as the gap ratio decreased or the heating ratio *** the calculation of enstrophy,it was found that the strength of shedding vortices weakens with a decrease in gap ratio or an increase in heating ***,the mean drag coefficient decreases as the heating ratio increases or the gap ratio *** contrast,the mean lift coefficient initially decreases and then increases as the gap ratio ***,the drag reduction mechanism was analyzed by examining the pressure distribution on the surface of the cylinder.

关键词： Compressible flow wall proximity heating effect stability enstrophy

Study on tungsten sintering temperature field based on electromagnetic simulation and computational fluid dynamics

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Tungsten 2024年第2期6卷 355-366页

作者： Lu-Yan Wang yue-Guang yu Jian-Xin Dong Kai-Ping Du Shan-yu liu Cao-Bing Li University of Science and Technology Beijing Beijing 100083China BGRIMM Technology Group Beijing 100160China China Iron&Steel Research Institute Group Beijing 100081China

In order to study the influence of various sintering variables more intuitively and clearly,electromagnetic field analysis and computational fl uid dynamics are used to analyze the infl uence of gas flow,heating power and other process parameters on the temperature range of medium-frequency sintering in this *** results indicate that the uniformity of temperature fi eld is determined by the gas flow rate and heating *** the heating power is 50 kW,the stable temperature drops about 10 K for every 1 m^(3)·h^(−1)increase of hydrogen *** peak value of the maximum temperature diff erence on the tungsten rods gradually increases with the increase of the hydrogen flow rate,and it appears slightly *** temperature distribution of tungsten rods in furnace is similar with diff erent hydrogen flow *** the same time,the closer to the furnace wall,the higher the temperature of the tungsten *** temperature diff erence between tungsten rods mainly occurred within 1 h after the beginning of *** the heating power can improve the stable temperature,but has little eff ect on the heating *** heating power can increase the peak value of the maximum temperature diff erence on the tungsten rods,but has little eff ect on the occurrence time of the peak value of the maximum temperature diff erence on the tungsten *** the heating power will increase the temperature diff erence of a single tungsten rod,but the temperature diff erence of a single tungsten rod never exceeds 65 *** study can be used to guide the process optimization *** with numerical simulation calculation,the sintering parameters with low energy consumption and high temperature uniformity can be quickly and eff ectively found,thus improving the microstructure and properties of sintered tungsten products.

关键词： Tungsten products Sintering Hydrogen flow rate Heating power

Ferroelectric-controlled graphene plasmonic surfaces for all-optical neuromorphic vision

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Science China(Technological Sciences) 2024年第3期67卷 765-773页

作者： CHEN JianBo liu yu LI ShangDong LIN Lin LI YaDong HUANG Wen GUO JunXiong School of Electronic Information and Electrical Engineering Institute for Advanced StudyChengdu UniversityChengdu 610106China School of Integrated Circuits Tsinghua UniversityBeijing 100084China School of Integrated Circuits(National Exemplary Schoolof Microelectronics) Universityof Electronic Science and Technologyof China Chengdu 610054China Jincheng Research Institute of Opto-mechatronics Industry Jincheng 048000China Shanxi Key Laboratory of Advanced Semiconductor Optoelectronic Devices and Integrated Systems Jincheng 048000China Engineering Research Center of Digital Imaging and Display Ministry of EducationSoochow UniversitySuzhou 215006China

Artificial visual systems can recognize desired objects and information from complex environments, and are therefore highly desired for pattern recognition, object detection, and imaging applications. However, state-of-the-art artificial visual systems with high recognition performances that typically consist of electronic devices face the challenges of requiring huge storage space and high power consumption owing to redundant data. Here, we report a terahertz(THz) frequency-selective surface using a graphene split-ring resonator driven by ferroelectric polarization for efficient visual system applications. The downward polarization of the ferroelectric material offers an ultrahigh electrostatic field for doping p-type graphene with an anticipated Fermi level. By optimizing the geometric parameters of the devices and modulating the carrier behaviors of graphene, our plasmonic devices exhibit a tunable spectral response in a range of 1.7–6.0 THz with continuous transmission values. The alloptical neural network using graphene plasmonic surfaces designed in this study exhibited excellent performance in visual preprocessing and convolutional filtering and achieved an ultrahigh recognition accuracy of up to 99.3% in training the Modified National Institute of Standards and Technology(MNIST) handwritten digit dataset. These features demonstrate the great potential of graphene plasmonic devices for future smart artificial vision systems.

关键词： graphene plasmon ferroelectric frequency selective surface artificial vision system

Colonoscopy plays an important role in detecting colorectal neoplasms in patients with gastric neoplasms

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World Journal of Gastrointestinal Oncology 2024年第1期16卷 133-143页

作者： Xu-Rui liu Ze-Lin Wen Fei liu Zi-Wei Li Xiao-yu liu Wei Zhang Dong Peng Department of Gastrointestinal Surgery The First Affiliated Hospital of Chongqing Medical UniversityChongqing 400016China Department of Gastrointestinal Surgery Yongchuan Hospital of Chongqing Medical UniversityChongqing 402160China

BACKGROUND Gastric cancer(GC)and colorectal cancer(CRC)are the fifth and third most common cancer worldwide,***,GC is reported to have a potential predictive value for CRC,especially for advanced *** To evaluate the necessity of colonoscopy for gastric neoplasm(GN)*** Four databases,including PubMed,EMBASE,the Cochrane Library,and Ovid,were used to perform the search strategy on May 2,*** prevalence of colorectal neoplasms(CRN)and baseline characteristics were compared between the neoplasm group and the control *** variables are expressed as the mean difference and standard *** of categorical variables in the two groups are expressed as odds ratios(OR)and 95%confidence intervals(95%CIs).Subgroup analysis according to different kinds of GNs was conducted for more in-depth *** results of this study are represented by forest *** bias was evaluated by a funnel *** data analyses were performed by STATA SE 16.0 *** A total of 3018 patients with GNs and 3905 healthy controls(age and sex matched)were enrolled for *** comparing the prevalence of CRNs between the two groups,CRNs were detected significantly more frequently in GN patients than in controls(OR=1.69,95%CI=1.28 to 2.23,I^(2)=85.12%,P=0.00),especially in patients with GC(OR=1.80,95%CI=1.49 to 2.18,I^(2)=25.55%,P<0.1).Moreover,other risk factors including age(OR=1.08,95%CI=1.00 to 1.17,I^(2)=90.13%,P=0.00)and male sex(OR=2.31,95%CI=1.26 to 4.22,I^(2)=87.35%,P=0.00),were related to the prevalence of *** patients in the GN group,body mass index(BMI,OR=0.88,95%CI=0.80 to 0.98,I^(2)=0.00%,P=0.92)and smoking(OR=1.03,95%CI=1.01 to 1.05,I^(2)=0.00%,P=0.57)were protective and risk factors for CRNs,*** Patients are recommended to undergo colonoscopy when diagnosed with GNs,especially GC patients with a low BMI and a history of smoking.

关键词： Gastric neoplasm Gastric cancer Colorectal neoplasm Colonoscopy

Metastatic clear cell sarcoma of the pancreas:A rare case report

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World Journal of Clinical Cases 2024年第8期12卷 1448-1453页

作者： yu-Jing liu Chen Zou Yong-You Wu General Surgery II Suzhou HospitalThe Affiliated Hospital of Medical SchoolNanjing UniversitySuzhou 215000Jiangsu ProvinceChina Department of General Surgery The Affiliated People's Hospital of Jiangsu UniversitySuzhou 215000Jiangsu ProvinceChina Department of Gastrointestinal Surgery The Second Affiliated Hospital of Soochow UniversitySuzhou 215008Jiangsu ProvinceChina

BACKGROUND Clear cell sarcoma(CCS)is a rare soft-tissue *** most common metastatic sites for CCS are the lungs,bones and *** is highly invasive and mainly metastasizes to the lung,followed by the bone and brain;however,pancreatic metastasis is relatively *** SUMMARY We report on a rare case of CCS with pancreatic metastasis in a 47-year-old *** patient had a relevant medical history 3 years ago,with abdominal pain as the main clinical *** abnormalities were observed on physical examination and the tumor was found on abdominal computed *** on the medical history and postoperative pathology,the patient was diagnosed with CCS with pancreatic *** patient was successfully treated with surgical interventions,including distal pancreatectomy and *** This report summarizes the available treatment modalities for CCS and the importance of regular postoperative follow-up for patients with CCS.

关键词： Clear cell sarcoma Pancreas Metastasis Follow-up Case report

Different effects of 24 dietary intakes on gastroesophageal reflux disease: A mendelian randomization

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World Journal of Clinical Cases 2024年第14期12卷 2370-2381页

作者： yu-Xin liu Wen-Tao Yang Yang Li Department of Oncology Hospital of Chengdu University of Traditional Chinese MedicineChengdu 610072Sichuan ProvinceChina Department of Cardiovascular Chengdu Integrated TCM&Western Medicine HospitalChengdu 610041Sichuan ProvinceChina Department of Nuclear Medicine Hospital of Chengdu University of Traditional Chinese MedicineChengdu 610072Sichuan ProvinceChina

BACKGROUND In observational studies,dietary intakes are associated with gastroesophageal re-flux disease(GERD).AIM To conduct a two-sample mendelian randomization(MR)analysis to determine whether those associations are *** To explore the relationship between dietary intake and the risk of GERD,we extracted appropriate single nucleotide polymorphisms from genome-wide asso-ciation study data on 24 dietary *** methods were adopted for data analysis:Inverse variance weighting,weighted median methods,and MR-Egger's *** odds ratio(OR)and 95%confidence interval(CI)were used to eva-luate the causal association between dietary intake and *** Our univariate Mendelian randomization(UVMR)results showed significant evidence that pork intake(OR,2.83;95%CI:1.76-4.55;P=1.84×10–5),beer intake(OR,2.70,95%CI:2.00-3.64;P=6.54×10–11),non-oily fish intake(OR,2.41;95%CI:1.49-3.91;P=3.59×10–4)have a protective effect on *** addition,dried fruit intake(OR,0.37;95%CI:0.27-0.50;6.27×10–11),red wine intake(OR,0.34;95%CI:0.25-0.47;P=1.90×10-11),cheese intake(OR,0.46;95%CI:0.39-0.55;P=3.73×10-19),bread intake(OR,0.72;95%CI:0.56-0.92;P=0.0009)and cereal intake(OR,0.45;95%CI:0.36-0.57;P=2.07×10-11)were negatively associated with the risk of *** was a suggestive asso-ciation for genetically predicted coffee intake(OR per one SD increase,1.22,95%CI:1.03-1.44;P=0.019).Multi-variate Mendelian randomization further confirmed that dried fruit intake,red wine intake,cheese intake,and cereal intake directly affected *** contrast,the impact of pork intake,beer intake,non-oily fish intake,and bread intake on GERD was partly driven by the common risk factors for ***,after adjusting for all four elements,there was no longer a suggestive association between coffee intake and *** This study provides MR evidence to support the causal relationship between a broad range of dietary intake and GERD,providing new insights for the treatment and p

关键词： Dietary Gastroesophageal reflux disease Mendelian randomization Disease management Randomized controlled trial

What benefit can be obtained from magnetic resonance imaging diagnosis with artificial intelligence in prostate cancer compared with clinical assessments?

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Military Medical Research 2024年第2期11卷 268-286页

作者： Li-Tao Zhao Zhen-yu liu Wan-Fang Xie Li-Zhi Shao Jian Lu Jie Tian Jian-Gang liu School of Engineering Medicine Beihang UniversityBeijing 100191China School of Biological Science and Medical Engineering Beihang UniversityBeijing 100191China CAS Key Laboratory of Molecular Imaging Institute of AutomationBeijing 100190China University of Chinese Academy of Sciences Beijing 100080China Department of Urology Peking University Third HospitalPeking UniversityBeijing 100191China Key Laboratory of Big Data‑Based Precision Medicine(Beihang University) Ministry of Industry and Information Technology of the People's Republic of ChinaBeijing 100191China Beijing Engineering Research Center of Cardiovascular Wisdom Diagnosis and Treatment Beijing 100029China

The present study aimed to explore the potential of artificial intelligence(AI)methodology based on magnetic resonance(MR)images to aid in the management of prostate cancer(PCa).To this end,we reviewed and summarized the studies comparing the diagnostic and predictive performance for PCa between AI and common clinical assessment methods based on MR images and/or clinical characteristics,thereby investigating whether AI methods are generally superior to common clinical assessment methods for the diagnosis and prediction fields of ***,we found that,in the included studies of the present study,AI methods were generally equal to or better than the clinical assessment methods for the risk assessment of PCa,such as risk stratification of prostate lesions and the prediction of therapeutic outcomes or PCa *** particular,for the diagnosis of clinically significant PCa,the AI methods achieved a higher summary receiver operator characteristic curve(SROC-AUC)than that of the clinical assessment methods(0.87 vs.0.82).For the prediction of adverse pathology,the AI methods also achieved a higher SROC-AUC than that of the clinical assessment methods(0.86 vs.0.75).Second,as revealed by the radiomics quality score(RQS),the studies included in the present study presented a relatively high total average RQS of 15.2(11.0–20.0).Further,the scores of the individual RQS elements implied that the AI models in these studies were constructed with relatively perfect and standard radiomics processes,but the exact generalizability and clinical practicality of the AI models should be further validated using higher levels of evidence,such as prospective studies and open-testing datasets.

关键词： Clinically significant prostate cancer Adverse pathology Radiomics quality score Artificial intelligence Magnetic resonance imaging

Cross section determination of^(27)Al(n,2n)^(26)Al reaction induced by 14-MeV neutrons uniting with D-T neutron activation and AMS techniques

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Nuclear Science and Techniques 2024年第6期35卷 78-89页

作者： Xian-Lin Yang Chang-Lin Lan yu-Ting Wei Yi Zhang Gong Jiang Bo Xie yu liu Hong-Tao Shen Xiao-Jun Sun School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China MOE Frontiers Science Center for Rare Isotopes Lanzhou UniversityLanzhou 730000China State Key Laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China Guangxi Key Laboratory of Nuclear Physics and Nuclear Technology Guangxi Normal UniversityGuilin 541004China

Aluminum is the primary structural material in nuclear engineering,and its cross section induced by 14-MeV neutrons is of great *** address the issue of insufficient accuracy for the^(27)Al(n,2n)^(26)Al reaction cross section,the activation method and accelerator mass spectrometry(AMS)technique were used to determine the^(27)Al(n,2n)^(26)Al cross section,which could be used as a D-T plasma ion temperature monitor in fusion *** the China Academy of Engineering Physics,neutron activation was performed using a K-400 neutron generator produced by the T(d,n)4He ***^(26)Al∕^(27)Al isotope ratios were measured using the newly installed GYIG 1 MV AMS at the Institute of Geochemistry,Chinese Academy of *** neutron flux was monitored by measuring the activity of 92mNb produced by the 93Nb(n,2n)92mNb *** measured results were compared with available data in the experimental nuclear reaction database,and the measured values showed a reasonable degree of consistency with partially available literature *** newly acquired cross-sectional data at 12 neutron energy points through systematic measurements clarified the divergence,which has two different growth trends from the existing experimental *** obtained results are also compared with the corresponding evaluated database,and the newly calculated excitation functions with TALYS−1.95 and EMPIRE−3.2 codes,the agreement with CENDL−3.2,TENDL-2021 and EMPIRE−3.2 results are generally acceptable.A substantial improvement in the knowledge of the^(27)Al(n,2n)^(26)Al reaction excitation function was obtained in the present work,which will lay the foundation for the diagnosis of the fusion ion temperature,testing of the nuclear physics model,evaluation of nuclear data,etc.

关键词： 14-MeV neutron ^(27)Al(n,2n)^(26)Al Cross section AMS

Salidroside Ameliorates Lung Injury Induced by PM_(2.5) by Regulating SIRT1-PGC-1αin Mice

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Biomedical and Environmental Sciences 2024年第4期37卷 367-376页

作者： LI Xiao Hong liu yu Mei SHAN Hui TAN Jin Feng ZHOU Jian SONG yuan Jin LI Si Qi liu Chen XU Dong Qun yu Li LI Wan Wei School of Public Health Shandong Second Medical UniversityWeifang 261053ShandongChina Key Laboratory of Health Inspection and Quarantine Weifang 261053ShandongChina Weifang Environmental Monitoring Station Weifang 261042ShandongChina Department of Orthopedics The 80th Army Hospital of PLAWeifang 261000ShandongChina Environment and Health Related Product Safety Institute of Chinese Center for Disease Control and Prevention Beijing 100021China School of Basic Medicine Shandong Second Medical UniversityWeifang 261053ShandongChina

Objective This study aimed to clarify the intervention effect of salidroside(SAL)on lung injury caused by PM_(2.5) in mice and illuminate the function of SIRT1-PGC-1ɑ*** Specific pathogen-free(SPF)grade male C57BL/6 mice were randomly assigned to the following groups:control group,SAL group,PM_(2.5) group,SAL+PM_(2.5) *** the first day,SAL was given by gavage,and on the second day,PM_(2.5) suspension was given by intratracheal *** whole experiment consist of a total of 10 cycles,lasting 20 *** the end of treatment,blood samples and lung tissues were collected and *** of pathological changes in lung tissue using inverted microscopy and transmission electron *** expression of inflammatory,antioxidants,apoptosis,and SIRT1-PGC-1ɑproteins were detected by Western *** Exposure to PM_(2.5) leads to obvious morphological and pathologica changes in the lung of ***_(2.5) caused a decline in levels of antioxidant-related enzymes and protein expressions of HO-1,Nrf2,SOD2,SIRT1 and PGC-1ɑ,and an increase in the protein expressions of IL-6,IL-1β,Bax,caspase-9 and cleaved ***,SAL reversed the aforementioned changes caused by PM_(2.5) by activating the SIRT1-PGC-1α *** SAL can activate SIRT1-PGC-1ɑ to ameliorate PM2.5-induced lung injury.

关键词： PM_(2.5) Salidroside Oxidative stress Inflammation Apoptosis SIRT1-PGC-1α