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Radiolarian transfer function for paleo-primary productivity in the South China Sea

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Chinese Science Bulletin 1999年第13期44卷 1232-1237页

作者： Muhong Chen liangmin Huang Xia Tu fan Zheng Chinese Acad Sci S China Sea Inst Oceanol Guangzhou 510301 Peoples R China

Basic data of radiolarian group and primary productivity were from 46 investigation stations of the South China Sea. The factor analysis of principal component and the least squares estimation in both linear regression and nonlinear estimation were applied to establishing the radiolarian transfer function for paleo-primary productivity in this sea area. The results show that the transfer function of nonlinear regression analysis for the radiolarian assemblage and primary productivity has much better parameters. Factors analysis has accumulating variance of 83.6% and communalities of more than 0.940347. Nonlinear regression analysis gives multiple correlation coefficient as 0.84888 and explained variance as 72.059%. The equation of transfer function is with an average estimated error of about 53.778 mg·C/m^2·d, which is 14.69% in average observed values. Calculation accuracy is 85.31% for the system of transfer function.

关键词： radiolarian paleo-primary productivity transfer function paleoceanography South China Sea.

Paradoxical herniation after decompressive craniectomy provoked by mannitol:A case report

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World Journal of Clinical Cases 2022年第15期10卷 4917-4922页

作者： Chuan Du Hua-Juan Tang Shuang-Ming fan Neurosurgery the Affiliated Hospital of Chengdu UniversityChengdu 610000Sichuan ProvinceChina Neurology West China HospitalSichuan UniversityChengdu 610000Sichuan ProvinceChina

BACKGROUND Paradoxical transtentorial herniation is a rare but life-threatening complication of cerebrospinal fluid drainage in patients with large decompressive ***,paradoxical transtentorial herniation after rapid intravenous infusion of mannitol has not been reported *** SUMMARY A 48-year-old male suffered from a right temporal vascular malformation with *** a coma,the patient was given emergency vascular malformation resection,hematoma removal,and the right decompressive *** patient woke up on the 1st d after the operation and was given 50 g of 20% mannitol intravenously every 8 h without cerebrospinal fluid *** the morning of the 7th postoperative day,after 50 g of 20% mannitol infusion in the Fowler’s position,the neurological function of the patient continued to deteriorate,and the right pupils dilated to 4 mm and the left to 2 ***,computed tomography revealed an increasing midline shift and transtentorial *** patient was placed in a supine position and given 0.9% saline intravenously.A few hours later,the patient was fully awake with purposeful movements on his right side and normal *** Paradoxical herniation may occur,although rarely,after infusing high-dose mannitol intravenously in the Fowler’s position in the case of a large craniectomy *** attempt should be made to place the patient in the supine position because this simple maneuver may be *** not use high-dose mannitol when the flap is severely sunken.

关键词： Decompressive craniectomy Intracranial hypotension Paradoxical herniation Transtentorial herniation Mannitol Case report

Virtual climbing: An immersive upslope walking system using passive haptics

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Virtual Reality & Intelligent Hardware 2021年第6期3卷 435-450页

作者： Liming WANG Xianwei CHEN Tianyang DONG Jing fan College of Computer Science and Technology Zhejiang University of TechnologyHangzhou 310023China

Background In virtual environments(VEs),users can explore a large virtual scene through the viewpoint operation of a head-mounted display(HMD)and movement gains combined with redirected walking *** existing redirection methods and viewpoint operations are effective in the horizontal direction;however,they cannot help participants experience immersion in the vertical *** improve the immersion of upslope walking,this study presents a virtual climbing system based on passive *** This virtual climbing system uses the tactile feedback provided by sponges,a commonly used flexible material,to simulate the tactile sense of a user's *** addition,the visual stimulus of the HMD,the tactile feedback of the flexible material,and the operation of the user's walking in a VE combined with redirection technology are all adopted to enhance the user's perception in a *** the experiments,a physical space with a hard-flat floor and three types of sponges with thicknesses of 3,5,and 8cm were *** We recruited 40 volunteers to conduct these experiments,and the results showed that a thicker flexible material increases the difficulty for users to roam and walk within a certain *** The virtual climbing system can enhance users'perception of upslope walking in a VE.

关键词： Virtual reality Redirected walking Passive haptic Flexible material

Computed tomography combined with gastroscopy for assessment of pancreatic segmental portal hypertension

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World Journal of Clinical Cases 2022年第24期10卷 8568-8577页

作者： Yu-Li Wang Han-Wen Zhang fan Lin Department of Radiology The First Affiliated Hospital of Shenzhen UniversityHealth Science CenterShenzhen Second People’s HospitalShenzhen 518035Guangdong ProvinceChina

BACKGROUND Pancreatic segmental portal hypertension(PSPH) is the only type of portal hypertension that can be completely cured. However, it can easily cause varicose veins in the esophagus and stomach and hemorrhage in the digestive *** To explore the application of computed tomography(CT) to examine the characteristics of PSPH and assess the risk *** This was a retrospective analysis of CT images of 22 patients diagnosed with PSPH at our center. Spearman correlation analysis was performed using the range of esophageal and gastric varices(measured by the vertical gastric wall), the ratio of the width of the splenic portal vein to that of the compression site(S/C ratio), the degree of splenomegaly, and the stage determined by gastroscopy. This study examined whether patients experienced gastrointestinal bleeding within 2 wk and combined CT and gastroscopy to explore the connection between bleeding and CT *** The range of esophageal and gastric varices showed the best correlation in the diagnosis of PSPH(P < 0.001), and the S/C ratio(P = 0.007) was correlated with the degree of splenomegaly(P = 0.021) and PSPH(P < 0.05). This study revealed that male patients were more likely than females to progress to grade 2 or grade 3 as determined by gastroscopy. CT demonstrated excellent performance, with an area under the curve of *** CT can be used to effectively analyze the imaging signs of PSPH, and CT combined with gastroscopy can effectively predict the risk level of gastrointestinal bleeding.

关键词： Computed tomography Pancreatic segmental portal hypertension esophageal and gastric varices Gastrointestinal bleeding Curable portal hypertension

Capturing driving behavior Heterogeneity based on trajectory data

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International Journal of Modeling, Simulation, and Scientific Computing 2020年第3期11卷 98-116页

作者： Dong-fan Xie Tai-Lang Zhu Qian Li School of Traffic and Transportation Beijing Jiaotong University BeijingP.R.China Key Laboratory of Transport Industry of Big Data Application Technologies for Comprehensive Transport Beijing Jiaotong University BeijingP.R.China China Academy of Transportation Science Beijing P.R.China

Driving behavior is heterogeneous for various drivers due to the different influencing factors as reaction time,gender,driving years and so *** existing works tried to reproduce some of the complex characteristics of real traffic flow by taking into account the heterogeneous driving behavior,and the drivers are generally divided into two classes(including aggressive drivers and careful drivers)or three classes(including aggressive drivers,normal drivers and careful drivers).Nevertheless,the classification approaches have not been verified,and the rationality of the classifications has not been confirmed as *** this study,the trajectory data of drivers is extracted from the NGSIM *** combining the K-Means method and Silhouette measure index,the drivers are classified into four clusters(named as clusters A,B,C and D,respectively)in accordance with the acceleration and time *** two-dimensional approach is applied to analyze the characteristics of different ***,one dimension consists of“Cautious”and“Aggressive”behaviors in terms of velocity and acceleration,and the other dimension consists of“Sensitive”and“Insensitive”behaviors in terms of reaction ***,the fuel consumption and emissions for different clusters are calculated by using the VT-Micro model.A surprising result indicates that overly“cautious”and“sensitive”behaviors may result in more fuel consumption and ***,it is necessary to find the balance between the driving characteristics.

关键词： Heterogeneous driving behavior trajectory data fuel consumption emissions

Secondary aortoesophageal fistula initially presented with empyema after thoracic aortic stent grafting:A case report

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World Journal of Clinical Cases 2021年第29期9卷 8938-8945页

作者： De-Qiong Wang Mei Liu Wen-Juan fan Department of Gastroenterology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030Hubei ProvinceChina

BACKGROUND Massive upper gastrointestinal(GI)bleeding is usually urgent and severe,and is mostly caused by GI *** fistula(AEF)after thoracic aortic stent grafting is a rare cause of this condition,and has a poor prognosis with a high mortality *** clinical symptoms of AEF are usually nonspecific,and the diagnosis is often difficult,especially when upper GI bleeding is *** identification,early diagnosis,and early treatment are very important for improving *** SUMMARY A 74-year-old man was admitted to the infectious disease department with>10-d fever and 10-mo prior history of thoracic aortic stent grafting for thoracic aortic penetrating *** tests revealed elevated inflammatory indicators and *** computed tomography(CT)showed postoperative changes of the aorta after endovascular stent graft implantation,pulmonary infection and pleural *** effusion tests showed *** 1 wk of anti-infective treatment,temperature returned to normal and chest CT indicated improvement in pulmonary infection and reduction of pleural *** endoscopy was performed because of epigastric discomfort,and showed a large ulcer with blood clot in the middle ***,on day 11,hematemesis and melena developed *** stopped temporarily after hemostatic treatment and bedside endoscopic *** and abdominal aortic CT angiography confirmed *** that day,he suffered massive hemorrhage and hemorrhagic ***,his family elected to discontinue *** AEF should be strongly considered in patients with a history of aortic intervention who present with fever,especially with empyema.

关键词： Gastrointestinal hemorrhage Esophageal fistula Esophageal perforation Thoracic aorta Empyema Case report

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基于投影余角的多普勒雷达几何检测器

系统工程与电子技术 2022年第6期44卷 1854-1861页

作者：梁璞范红旗付强国防科技大学电子科学学院ATR重点实验室湖南长沙410073 中国人民解放军96747部队青海西宁810007

针对多普勒雷达信号检测问题,基于几何代数工具重新审视离散傅里叶变换,提出了一种以投影余角为检验统计量的多普勒雷达几何检测器。该检测器相对传统功率/包络检测器具有良好的动态压缩性质与恒虚警特性。通过与现有功率/包络恒虚警检... 详细信息

针对多普勒雷达信号检测问题,基于几何代数工具重新审视离散傅里叶变换,提出了一种以投影余角为检验统计量的多普勒雷达几何检测器。该检测器相对传统功率/包络检测器具有良好的动态压缩性质与恒虚警特性。通过与现有功率/包络恒虚警检测器的对比试验,表明了几何检测器对背景起伏与强多音信号干扰的优良适应能力,为雷达检测器设计提供了一种新的视角和工具。

关键词：信号检测多普勒雷达几何检测器几何代数背景起伏多目标干扰

Synthesis,characterization and applications of vinylsilafluorene copolymers:New host materials for electroluminescent devices

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Science China Chemistry 2010年第11期53卷 2329-2336页

作者： CHEN Runfeng ZHU Rui ZHENG Chao fan QuLi HUANG Wei Key Laboratory for Organic Electronics&Information Displays(KLOEID) Institute of Advanced Materials(IAM)Nanjing University of Posts and Telecommunications(NUPT)Nanjing 210046China

Vinylsilafluorene(VSiF) was successfully synthesized and copolymerized with vinylcarbazole and methyl methacrylate via free radical copolymerization for the first *** synthesis,photophysical properties,computational modeling studies,and organic light-emitting devices of the VSiF copolymers were *** good coordinated photoluminescent(PL) spectra with the absorption of blue light-emitting materials and the high energy band-gap of the VSiF copolymers were *** triplet band gap(3Eg) to host the blue phosphorescent emitters and better HOMO and LUMO than PVK for electron and hole injection and transportation of the VSiF model compounds were revealed by density functional theory(DFT) *** preliminary device results in applications of these copolymers as host materials for green phosphorescent emitters demonstrate the copolymers of VSiF and vinylcarbazole have comparable device performance of polyvinylcarazole(PVK),suggesting a bright future of VSiF as building blocks for host materials.

关键词： vinylsilafluorene host materials polyvinylsilafluorene

Multitaper spectral method to estimate the elastic thickness of South China: Implications for intracontinental deformation

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Geoscience Frontiers 2014年第2期5卷 193-203页

作者： Yangfan Deng Zhongjie Zhang Weiming fan Marta Pérez-Gussinyé State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Guangzhou Institute of Geochemistry Chinese Academy of Science Department of Earth Sciences Royal Holloway University of London

The effective elastic thickness （Te） represents the thickness of the elastic layer or the flexural rigidity of the lithosphere, the equivalent of which can be calculated from the spectral analysis of gravity and topographic data. Studies of Te have profound influence on intracontinental deformation, and coupling of the tectonic blocks. In this paper, we use the multitaper spectral estimation method to calculate the coherence between Bouguer gravity and topography data, and to obtain the Te map of South China. Through the process of correction, we discuss the relationships of Te versus heat flow, and Te versus seismicity. The results show that Te distribution of South China is affected by three factors：the original age, which controls the basic feature;the Mesozoic evolution, which affects the Te distribution;and the neotectonic movement, which shaped the final distribution. The crust age has a positive correlation with the first-order Te distribution;thus the Yangtze Craton has a relatively higher Te （about 50 km） whereas the Te in Cathaysia block is only 10e20 km. By analysis and comparison among the tectonic models of South China, the Te distribution can be well explained using the flat-subduction model. As is typical with neotectonics, the region with a higher heat flow is related with a lower Te. The seismicity does not have a clear relationship with Te, but the strong seismicity could cause a low Te. Seismogenic layer （Ts） has a similar trend as Te in the craton, whereas in other areas the relationship is complex.

关键词： South China Effective elastic thickness Spectrum estimation Heat flow Seismicity