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Turbidite deposition in the southern South China Sea during the last glacial: Evidence from grain-size and major elements records

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Chinese Science Bulletin 2011年第33期56卷 3558-3565页

作者： ZHAO YuLong LIU ZhiFei COLIN Christophe xie Xin WU qiong State Key Laboratory of Marine Geology Tongji University Shanghai 200092 China Laboratoire des Interactions et Dynamique des Environnements de Surface （IDES） UMR 8148 CNRS-Universite Paris-Sud I 1 Orsay 91405 France

High-resolution grain size and major element geochemical measurements were performed on the marine sediments of Core MD05-2895 to help understand the formation of turbidite sequences. Grain-size results show that these turbidite sediments contain more coarse sediment grains than normal marls. The coarse sediment grains are mostly derived from relict sediments on the Sunda Shelf. Relict sediments are composed mainly of quartz, feldspar, tephra and a few titaniferous or ferruginous heavy minerals. Corresponding to the concentration of these minerals, increases in Si/Al, K/Al, Ti/Al and Fe/Al ratios are observed in the turbidite layers. As all the observed turbidite sequences were deposited during the last glacial, the occurrence of these turbidity events is implied to be closely related to instabilities in sea-level-induced sediment supply. We suggest that deposition of sediment particles from a single turbidity current is usually controlled by a counterbalance between gravity and buoyancy, with the interaction of individual grains being of minor importance.

关键词：浊流沉积末次冰期南海南部粒度海洋沉积物证据中国地球化学测量

Effects of river width changes on flow characteristics based on flume experiment

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Journal of Mountain Science 2016年第2期13卷 361-368页

作者： WANG xie-kang WANG Bing-jie LIU Xing-nian Zhang Li-qiong State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University Hydrology and Hydraulics Section South Florida Water Management District

The rapid changes in flow pattern due to varying channel widths will make significantly impact on the hydraulic structures and evolutions of open channel. To better understand the impact of varying width, a flume experiment with adjustable width and a depth-averaged two-dimension numerical model were used to analyze the variations of flow parameters. Our experimental results showed that flow velocity gradually increased with decreasing water depth in converging region, and decreased with increasing water depth in diverging zones. It was also found that the turbulence intensity laws in three directions were not agreed with the theoretical relationships proposed by Nezu and Nakagawa in 1993 in straight open channel flows. The flow in the channel with varying width may change from the supercritical flow to the subcritical flow as a function of Froude number. Our numerical simulations with different flow rates showed that most of the hydraulic jumps in diverging region were submerged jump and the degree of submergence increased with increasing flow rate in gradual channel transition. When the flow rate increased, the range of supercritical flow rapidly decreased and the flow changed from the supercritieal condition to the subcritical condition in diverging sections.

关键词： Gradual channel transition Flow pattern Experimental study Numerical simulation

Signet-ring cell carcinoma of the transverse colon in a 10-year-old girl:A case report

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World Journal of Gastrointestinal Oncology 2024年第12期16卷 4746-4752页

作者： Ling Lv Yuan-Hua Song Yan Gao Shuang-qiong Pu Zhi-Xiang A hong-Fang Wu Jun Zhou Yu-Cheng xie Department of Pathology Kunming Children’s HospitalKunming 650028Yunnan ProvinceChina Department of Oncology Kunming Children’s HospitalKunming 650028Yunnan ProvinceChina

BACKGROUND Signet-ring cell carcinoma(SRCC)is a rare subtype of colorectal *** incidence of primary colonic SRCC is relatively rare in pediatric patients,with a limited number of reported cases currently *** prognosis for this specific tumor type is unfavorable,and the preoperative diagnosis presents challenges,potentially leading to *** case report describes the diagnosis of primary SRCC in the colon of a 10-year-old *** SUMMARY The patient was admitted to the hospital due to abdominal pain and vomiting.A computed tomography scan revealed an irregular mass with soft tissue density in her transverse colon,showing uneven density and multiple *** patient underwent surgical resection of the affected bowel and lymph node dissection,which was confirmed by pathological examination to be SRCC infiltrating both nerves and the entire intestinal ***,tumor thrombus formation was observed in blood vessels and lymphatic vessels,multiple cancerous nodules were found in the omentum,and metastasis to 18 of 26 mesenteric lymph nodes *** for mismatch repair gene protein demonstrated microsatellite *** mutations in KRAS,NRAS,BRAF,or PIK3CA genes were detected through molecular pathology *** surgery,she received standard chemotherapy for 8 cycles without tumor progression or other abnormalities during a 12-month follow-up period CONCLUSION Primary colonic SRCC is a rare malignant tumor with atypical clinical symptoms,and timely identification and intervention are crucial for improving the prognosis.

关键词： Signet ring cell cancer Colon Pediatric Pathological presentation Case report

Stromal lenticule addition keratoplasty with corneal crosslinking for corneal ectasia secondary to FS-LASIK:a case series

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International Journal of Ophthalmology(English edition) 2024年第3期17卷 596-602页

作者： Li-Xiang Wang Ying-Ping Deng Meng-Zhen xie Ke Ma hong-Bo Yin qiong Wang Rui Gong Jing Tang Department of Ophthalmology West China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina West China School of Medicine Sichuan UniversityChengdu 610041Sichuan ProvinceChina

●AIM:To explore the clinical efficacy and safety of stromal lenticule addition keratoplasty(SLAK)with corneal crosslinking(CXL)on patients with corneal ectasia secondary to femtosecond laser-assisted in situ keratomileusis(FS-LASIK).●METHODS:A series of 5 patients undertaking SLAK with CXL for the treatment of corneal ectasia secondary to FS-LASIK were followed for *** lenticules were collected from patients undertaking small incision lenticule extraction(SMILE)for the correction of *** a stromal lenticule was aimed at improving the corneal thickness for the safe application of crosslinking and compensating for the thin cornea to improve its mechanical strength.●RESULTS:All surgeries were conducted successfully with no significant *** best corrected visual acuity(BCVA)ranged from 0.05 to 0.8-2 before *** pre-operational total corneal thickness ranged from 345-404μm and maximum keratometry(Kmax)ranged from 50.8 to *** the combination surgery,both the corneal keratometry(range 55.9 to 92.8)and total corneal thickness(range 413-482μm)significantly *** out of 5 patients had improvement of corneal biomechanical parameters(reflected by stiffness parameter A1 in Corvis ST).However,3 patients showed decreased BCVA after surgery due to the development of irregular astigmatism and transient *** the onset of corneal edema right after SLAK,the corneal topography and thickness generally stabilized after 3mo.●CONCLUSION:SLAK with CXL is a potentially beneficial and safe therapy for advanced corneal *** work needs to address the poor predictability of corneal refractometry and compare the outcomes of different surgical modes.

关键词： corneal ectasia femtosecond laserassisted in situ keratomileusis stromal lenticule addition keratoplasty corneal crosslinking corneal thickness corneal biomechanics

All-day perception for intelligent vehicles: switching perception algorithms based on WBCNet

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Science China(Information Sciences) 2024年第11期67卷 269-284页

作者： hongbin xie Haiyan ZHAO Chengcheng XU hong CHEN College of Communication Engineering Jilin University College of Electronic and Information Engineering Tongji University

A weather-and brightness-based classification network(WBCNet) is proposed for driving scene classification to address the decreased accuracy in perception caused by weather and environment *** facilitate its applicability in vehicles and minimize computational demands on vehicle chips, WBCNet has been designed with special modules, including attention mechanisms and dilated convolutions. Dilated convolutions combined with residual connections empower WBCNet to concurrently handle information at various scales. This aids in simplifying the training and optimization of deep networks, consequently enhancing the model's performance and mitigating the risk of overfitting. The outstanding feature association capability originating from the fusion of channel attention and spatial attention enables WBCNet to focus more on the sky, lanes, and other traffic information features within the image. This design enables WBCNet to use only images as input, making it highly suitable for engineering applications. The output of WBCNet provides the basis for the downstream perception model selection algorithm, allowing it to choose the appropriate perception model for different scenes accurately. A dataset with complex scenes based on Carla is constructed for comparison to verify WBCNet's performance. Finally, a real-world driving dataset is used to validate the effectiveness and real-time performance of WBCNet.

关键词： driving scene classification intelligent vehicle safe driving convolutional neural network attention mechanism

Non-isothermal Crystallization Kinetics of Polyamide 6/Diaminemodified MWNTs Nanocomposite

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Journal of Materials Science & Technology 2009年第2期25卷 145-150页

作者： hong Meng Guoxin Sui Guangyou xie Rui Yang Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

The non-isothermal crystallization kinetics of polyamide 6/diamine-modified multi-walled carbon nanotube （PA6/D-MWNT） nanocomposite was investigated by differential scanning calorimetry （DSC）. The modified Avrami equation, the Ozawa equation and the combined Avrami/Ozawa equation were employed to analyze the non-isothermal crystallization data. The crystallization activation energies were also evaluated by the Kissinger method. It was found that the combined Avrami/Ozawa equation could successfully describe the non-isothermal crystallization process. The results showed that D-MWNTs not only acted as effective heterogeneous nucleating agents for PA6 and noticeably increased the crystallization temperature of PA6, but also influenced the mechanism of nucleation and crystal growth of PA6 and then reduced the overall crystallization rate of the neat PA6 matrix. The crystallization activation energy for the nanocomposite sample was greater than that of the neat PA6, which indicated that the addition of D-MWNTs hindered the mobility of PA6 chain segments.

关键词： Non-isothermal crystallization kinetics Carbon nanotubes Polyamide 6

Accuracy estimation of link-based similarity measures and its application

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Frontiers of Computer Science 2016年第1期10卷 113-123页

作者： Yinglong ZHANG Cuiping LI Chengwang xie hong CHEN School of Software East China Jiaotong University Nanchang 330045 China Key Laboratory of Data Engineering and Knowledge Engineering of Ministry of Education and Department of Computer Science Renmin University of China Beijing 100872 China Intelligent Optimization and Information Processing Laboratory East China Jiaotong University Nanchang 330013 China

Link-based similarity measures play a significant role in many graph based applications. Consequently, mea- suring node similarity in a graph is a fundamental problem of graph data mining. Personalized PageRank （PPR） and Sim- Rank （SR） have emerged as the most popular and influen- tial link-based similarity measures. Recently, a novel link- based similarity measure, penetrating rank （P-Rank）, which enriches SR, was proposed. In practice, PPR, SR and P-Rank scores are calculated by iterative methods. As the number of iterations increases so does the overhead of the calcula- tion. The ideal solution is that computing similarity within the minimum number of iterations is sufficient to guaran- tee a desired accuracy. However, the existing upper bounds are too coarse to be useful in general. Therefore, we focus on designing an accurate and tight upper bounds for PPR, SR, and P-Rank in the paper. Our upper bounds are designed based on the following intuition： the smaller the difference between the two consecutive iteration steps is, the smaller the difference between the theoretical and iterative similar- ity scores becomes. Furthermore, we demonstrate the effec- tiveness of our upper bounds in the scenario of top-k similar nodes queries, where our upper bounds helps accelerate the speed of the query. We also run a comprehensive set of exper- iments on real world data sets to verify the effectiveness and efficiency of our upper bounds.

关键词： personalized PageRank SimRank P-Rank up-per bound

An energy harvester combining a piezoelectric cantilever and a single degree of freedom elastic system

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第7期13卷 526-537页

作者： hong-yan WANG Xiao-biao SHAN Tan xie State Key Laboratory of Robotics and System Harbin Institute of Technology Harbin 150001China College of Computer and Control Engineering Qiqihar UniversityQiqihar 161006China

This paper presents a type of vibration energy harvester combining a piezoelectric cantilever and a single degree of freedom (SDOF) elastic system. The main function of the additional SDOF elastic system is to magnify vibration displacement of the piezoelectric cantilever to improve the power output. A mathematical model of the energy harvester is developed based on Hamilton's principle and Rayleigh-Ritz method. Furthermore, the effects of the structural parameters of the SDOF elastic system on the electromechanical outputs of the energy harvester are analyzed numerically. The accuracy of the output performance in the numerical solution is identified from the finite element method (FEM). A good agreement is found between the numerical results and FEM results. The results show that the power output can be increased and the frequency bandwidth can be improved when the SDOF elastic system has a larger lumped mass and a smaller damping ratio. The numerical results also indicate that a matching load resistance under the short circuit resonance condition can obtain a higher current output, and so is more suitable for application to the piezoelectric energy harvester.

关键词： Piezoelectric cantilever Single degree of freedom elastic (SDOF) system Energy harvesting Finite element analysis(FEA)

Characteristics of gut microbiota dysbiosis in patients with colorectal polyps

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World Journal of Gastrointestinal Oncology 2025年第1期17卷 13-21页

作者： Xian-Rong Wu Xiao-hong He Yong-Fang xie School of Life Health Information Science and Engineering Chongqing Post and Communications UniversityChongqing 400065China

This editorial,inspired by a recent study published in the World Journal of Gastrointestinal Oncology,covers the research findings on microbiota changes in various *** recurrent colorectal polyps,the abundances of Klebsiella,Parvimonas,and Clostridium increase,while those of Bifidobacterium and Lactoba-cillus *** dysbiosis may promote the formation and recurrence of *** microbial changes have also been observed in colorectal cancer,inflammatory bowel disease,autism spectrum disorder,and metabolic syndrome,indicating the role of increased pathogens and decreased probiotics in these *** the gut microbiota,particularly by increasing probiotic levels,may help prevent polyp recurrence and promote gut *** microbial intervention strategy holds promise as an adjunctive treatment for patients with colorectal polyps.

关键词： Recurrent colorectal polyps Gut microbiota dysbiosis Klebsiella Probiotics Intestinal inflammation Microbial intervention strategy