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Second-order random interfacial wave solutions for two-layer fluid with a free surface

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Acta Oceanologica Sinica 2006年第1期25卷 15-20页

作者： SONG Jinbao sun qun Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China

A previous study （Song. 2004. Geophys Res Lett, 31 （15）：L15302） of the second-order solutions for random interracial waves is extended in a constant depth, two-layer fluid system with a rigid lid is extended into a more general case of two-layer fluid with a top free surface. The rigid boundary condition on the upper surface is replaced by the kinematical and dynamical boundary conditions of a free surface, and the equations describing the random displacements of free surface, density-interface and the associated velocity potentials in the two-layer fluid are solved to the second order using the same expansion technology as that of Song （2004. Geophys Res Lett, 31 （15）：L15302）. The results show that the interface and the surface will oscillate synchronously, and the wave fields to the first-order both at the free surface and at the density-interface are made up of a linear superposition of many waves with different amplitudes, wave numbers and frequencies. The second-order solutions describe the second-order wave-wave interactions of the surface wave components, the interface wave components and among the surface and the interface wave components. The extended solutions also include special cases obtained by Thorpe for progressive interracial waves （Thorpe. *** R Soc London, 263A：563～614） and standing interracial waves （Thorpe. 1968b. J Fluid Mech, 32：489-528） for the two-layer fluid with a top free surface. Moreover, the solutions reduce to those derived for random surface waves by Sharma and Dean （*** Engineering Rep 20） if the density of the upper layer is much smaller than that of the lower layer.

关键词： two-layer fluid free surface random interracial waves second-order solutions

Effect of Stokes drift on upper ocean mixing

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Acta Oceanologica Sinica 2008年第2期27卷 11-20页

作者： LI Shuang SONG Jinbao sun qun Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China Graduate School Chinese Academy of Sciences Beijing 100039 China

Stokes drift is the main source of vertical vorticity in the ocean mixed layer. In the ways of Coriolis - Stokes forcing and Langmuir circulations, Stokes drift can substantially affect the whole mixed layer. A modified Mellor-Yamada 2. 5 level turbulence closure model is used to parameterize its effect on upper ocean mixing conventionally. Results show that comparing surface heating with wave breaking, Stokes drift plays the most important role in the entire ocean mixed layer, especially in the subsurface layer. As expected, Stokes drift elevates both the dissipation rate and the turbulence energy in the upper ocean mixing. Also, ilffluence of the surface heating, wave breaking and wind speed on Stokes drift is investigated respectively. Research shows that it is significant and important to assessing the Stokes drift into ocean mixed layer studying. The laboratory observations are supporting numerical experiments quantitatively.

关键词： Stokes drift Langmuir circulations Coriolis - Stokes forcing upper ocean mixing Mellor-Yamada 2. 5 turbulence model wave breaking surface heating

Ulcerative colitis complicated with colonic necrosis, septic shock and venous thromboembolism: A case report

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World Journal of Clinical Cases 2019年第16期7卷 2360-2366页

作者： Ming-Yu Zhu Li-qun sun Critical Care Unit the Second Affiliated Hospital of Nanjing Medical University

BACKGROUND Severe total colonic necrosis,septic shock and venous thromboembolism secondary to ulcerative colitis (UC) are rare and *** such severe complications have been reported in the *** SUMMARY We report a 36-year-old woman who developed total colonic necrosis and septic shock secondary to *** patient was treated with emergency surgery because computed tomography showed suspicious *** massive ascites occurred after operation and computed tomography angiography demonstrated portal vein,mesenteric vein and splenic vein *** patient was discharged from hospital after active *** Clinicians should pay attention to venous thrombosis,colonic necrosis and septic shock in UC *** observation of surgical indications and timely surgical intervention are the key to reduce mortality and complications in UC.

关键词： Ulcerative colitis Total colonic necrosis Venous thromboembolism Sepsis Septic shock Case report

Advances on Seed Vigor Physiological and Genetic Mechanisms

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Agricultural Sciences in China 2007年第9期6卷 1060-1066页

作者： sun qun WANG Jian-hua sun Bao-qi Department of Seed Science College of Agriculture and Biotechnology China Agricultural University Beijing 100094 P.R.China

Seed vigor is a more promising seed quality character reflecting potential seed germination, field emergence and seed storage ability under different conditions than standard germination. Standard germination is influenced by genetic background and environmental effects during seed development and storage conditions. The latest research on physiological mechanism in seed vigor showed that at the late stage of seed development, the development of seed vigor involves some stress-resistant substances including late embryogenesis abundant （LEA） protein, oligosaccharides and abscisic acid （ABA）. Whereas the loss of seed vigor, or seed aging and deterioration, could be attributed to lipid peroxidation, chromosome deformation and genes aberrance, and embryo protein degradation, etc. Seed vigor is a quantitative character controlled by multi-genes. Genetic and quantitative trait locus （QTL） analyses on seed-vigor trait in model plants, such as Arabidopsis and rice, are mostly concentrated on related morphology traits, whereas few physiological traits have been researched. It was concluded that, all of the QTL genetic characteristics of seed vigorincluding QTL quantities, its locus on chromosome, genetic effects, and interaction effects between genetic and environment, differed with plant species and used seed-vigor traits.

关键词： seed vigor physiological and genetic mechanism QTL analyses

Vehicle Active Steering Control Research Based on Two-DOF Robust Internal Model Control

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Chinese Journal of Mechanical Engineering 2016年第4期29卷 739-746页

作者： WU Jian LIU Yahui WANG Fengbo BAO Chunjiang sun qun ZHAO Youqun School of Mechanical and Automotive Engineering Liaocheng University State Key Laboratory of Automotive Safety and Energy Tsinghua University College of Energy and Power Engineering Nanjing University of Aeronautics and Astronautics

Because of vehicle＇s external disturbances and model uncertainties,robust control algorithms have obtained popularity in vehicle stability *** robust control usually gives up performance in order to guarantee the robustness of the control algorithm,therefore an improved robust internal model control（IMC） algorithm blending model tracking and internal model control is put forward for active steering system in order to reach high performance of yaw rate tracking with certain *** proposed algorithm inherits the good model tracking ability of the IMC control and guarantees robustness to model *** order to separate the design process of model tracking from the robustness design process,the improved 2 degree of freedom（DOF） robust internal model controller structure is given from the standard Youla *** of double lane change maneuver and those of crosswind disturbances are conducted for evaluating the robust control algorithm,on the basis of a nonlinear vehicle simulation model with a magic tyre *** show that the established 2-DOF robust IMC method has better model tracking ability and a guaranteed level of robustness and robust performance,which can enhance the vehicle stability and handling,regardless of variations of the vehicle model parameters and the external crosswind *** between performance and robustness of active steering control algorithm is solved and higher control performance with certain robustness to model uncertainties is obtained.

关键词： active steering internal model control model tracking robust performance crosswind disturbances

Interannual variability of dimethylsulfide in the Yellow Sea

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Journal of Oceanology and Limnology 2022年第2期40卷 551-562页

作者： Sijia WANG qun sun Siyu LI Jiawei SHEN Qian LIU Liang ZHAO College of Marine and Environmental Sciences Tianjin University of Science and TechnologyTEDATianjin 300222China School of Marine Science and Technology Tianjin UniversityTianjin 300072China

The 22-year(1998-2019)surface seawater dimethylsulfi de(DMS)concentrations in the Yellow Sea(YS)were hindcasted based on satellite sea surface temperature(SST)and chlorophyll-a(Chl-a)data using a generalized additive mixed model(GAMM).A continuous monthly dataset of DMS concentration in the YS was obtained after using the data interpolation empirical orthogonal function(DINEOF)to reconstruct missing information in the ***,the interannual DMS variability in the YS was *** results indicated that the monthly climatological DMS concentration in the YS was 3.61 nmol/*** concentrations in the spring and summer were signifi cantly higher than those in the autumn and *** concentrations were highest in coastal YS waters and lowest primarily in off shore YS *** DMS variability between 1998 and 2019 was subdivided into two inverse phases:with the exception of the central YS,DMS increased before the turning point and decreased *** turning point in interannual DMS variation was earlier in the inshore YS as compared to the central *** analysis identifi ed some signifi cant patterns of interannual variation in the DMS anomaly in the *** a appeared to be the main factor infl uencing interannual trends in DMS in the *** DMS variability was under the joint control of Chl a and ***,short-term interannual DMS variation(2-3 years)was primarily related to SST,while longer term interannual DMS variation(6-8 years)was signifi cantly correlated with Chl a and SST.

关键词： interannual variability dimethylsulfi de hindcasting generalized additive mixed modelling Yellow Sea

High level of ezrin expression in colorectal cancer tissues is closely related to tumor malignancy

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World Journal of Gastroenterology 2009年第16期15卷 2016-2019页

作者： Hong-Jian Wang Jin-Shui Zhu Qiang Zhang qun sun Hua Guo Department of Gastroenterology The Sixth People's Hospital Affiliated to Shanghai Jiao Tong University Shanghai 200233 China

AIM:To investigate the ezrin expression in normal colorectal mucosa and colorectal cancer tissues, and study the correlation between ezrin expression in colorectal cancer tissues and tumor invasion and ***: Eighty paraffin-embedded cancer tissue samples were selected from primary colorectal adenocarcinoma. Twenty-eight patients had well-differentiated, 22 had moderately differentiated and 30 had poorly differentiated adenocarcinoma. Forty-five patients and 35 patients had lymph node metastasis. Forty-five patients were of Dukes A to B stage, and 35 were of C to D stage. Another 22 paraffi n-embedded tissue blocks of normal colorectal epithelium (>5 cm away from the edge of the tumor) were selected as the control group. All patients with colorectal cancer were treated surgically and diagnosed histologically, without preoperative chemotherapy or radiotherapy. The immunohistochemistry was used to detect the ezrin expression in paraffin-embedded normal colorectal mucosa tissues and colorectal cancer tissue ***: Ezrin expression in colorectal cancer was significantly higher than in normal colorectal mucosa (75.00% vs 9.09%, P<0.01), and there was a close relationship between ezrin expression and the degree of tumor differentiation, lymph node metastasis and Dukes stage (88.46% vs 50.00%, P<0.01; 94.28% vs 51.11%, P<0.01; 94.28% vs 51.11%, P<0.01).CONCLUSION: Ezrin expression is obviously higher in colorectal cancer tissues than in normal colorectal mucosa tissues, and the high level of ezrin expression is closely related to the colorectal cancer invasion and metastasis process.

关键词： Colorectal cancer Ezrin Malignant tumor Invasion Metastasis Immunohistochemistry

Elevated serum levels of ghrelin and TNF-a in patients with cyanotic and acyanotic congenital heart disease

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World Journal of Pediatrics 2017年第2期13卷 122-128页

作者： Sai Zhang Gong-Liang Guo Li-Li Yang Li-qun sun Outpatient Department of Pediatrics No.1 Hospiml of Jilin UniversityChangchunChina Department of Cardiology the Third Hospital ofJilin UniversityChangchunChina Department of Gynecology and Obstetrics No.1 Hospital of Jilin UniversityChangchunChina

Background:The levels of ghrelin and tumor necrosis factor alpha (TNF-a) are considered biological markers of congenital heart diseases (CHD).The present meta-analysis was conducted to investigate the clinical significance of serum levels of ghrelin and TNF-α in children with (CHD).Methods:Chinese and English scientific literature databases were searched to retrieve published studies relevant to ghrelin,TNF-α and *** search was additionally employed to identify other relevant studies from *** retrieved studies were screened on the basis of our stringent inclusion and exclusion criteria to select high quality case-control studies for ***:We initially retrieved 108 published studies (20 in Chinese and 88 in English) from database ***,6 case-control studies (5 in English and 1 in Chinese) were enrolled in our meta-analysis,and contained a total of 160 cyanotic congenital heart disease (CCHD) patients and 215 acyanotic congenital heart disease (ACHD) patients,along with 162 healthy *** results of meta-analysis showed that serum levels of ghrelin and TNF-α in CCHD or ACHD children were significantly higher than those in healthy ***:Our meta-analysis results showed that serum levels of ghrelin and TNF-α are elevated in children with CHD,and could be used as effective biologic markers in early diagnosis of CHD.

关键词： acyanotic congenital heart disease cyanotic ghrelin meta-analysis TNF-α

Discrimination of individual seed viability by using the oxygen consumption technique and headspace-gas chromatography-ion mobility spectrometry

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Journal of Integrative Agriculture 2023年第3期22卷 727-737页

作者： TU Ke-ling YIN Yu-lin YANG Li-ming WANG Jian-hua sun qun Department of Seed Science and Biotechnology College of Agronomy and BiotechnologyChina Agricultural University/The Innovation Center(Beijing)of Crop Seeds Whole-Process Technology ResearchMinistry of Agriculture and Rural Affairs/Beijing Key Laboratory of Crop Genetic ImprovementBeijing 100193P.R.China College of Arts and Science of Hubei Normal University Huangshi 435109P.R.China College of Science China Agricultural UniversityBeijing 100083P.R.China

Identifying and selecting high-quality seeds is crucial for improving crop *** purpose of this study was to improve the selection of crop seeds based on separating vital seeds from dead seeds,by predicting the potential germination ability of each seed,and thus improving seed *** methods of oxygen consumption (Q) of seeds and the headspace-gas chromatography-ion mobility spectrometry(HS-GC-IMS) were evaluated for identifying the viability of individual ***,the oxygen consumption technique showed clear differences among the values related to respiratory characteristics for seeds that were either vital or not,and the discrimination ability of final oxygen consumption(Q_(120)) was achieved not only in sweet corn seeds but also in pepper and wheat ***,Qtwas established as a new variable to shorten the measuring process in the Q2 (oxygen sensor) procedure,which was significantly related to the viability of individual *** minimize seed damage during measurement,the timing for viability evaluation was pinpointed at the 12,6 and 9 h for pepper,sweet corn,and wheat seeds based on the new variables concerning oxygen consumption (i.e.,Q_(12),Q_(6)and Q_(9),respectively).The accuracies of viability prediction were 91.9,97.7 and 96.2%,*** seeds were identified and hence discarded,leading to an enhancement in the quality of the seed lot as indicated by an increase in germination percentage,from 86.6,90.9,and 53.8%to all at 100%.We then used the HS-GC-IMS to determine the viability of individual sweet corn seeds,noting that corn seed has a heavier weight so the volatile gas components are more likely to be detected.A total of 48 chromatographic peaks were identified,among which 38 target compounds were characterized,including alcohols,aldehydes,acids and ***,there were no significant differences between the vital and dead seeds,due to the trace amount volatile composition differences among the individual ***

关键词： headspace-gas chromatography-ion mobility spectrometry oxygen consumption seed respiration sweet corn tomato wheat