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Hamiltonian Theory for the DNLS Equation with a Squared Spectral Parameter

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Wuhan University Journal of Natural Sciences 2010年第4期15卷 315-319页

作者： Jin Zhang tian yan Hao Cai School of Physics and Technology Wuhan University Wuhan Hubei China

With a special gauge transformation,the Lax pair of the derivative nonlinear Shcrdinger (DNLS) equation turns to depend on the squared parameter λ = k2instead of the usual spec-tral parameter k. By introducing a new direct product of Jost solu-tions,the complete Hamiltonian theory of the DNLS equation is constructed on the basis of the squared spectral parameter,which shows that the integrability completeness is still preserved. This result will be beneficial to the further study of the DNLS equation,such as the direct perturbation method.

关键词： DNLS equation Hamiltonian theory squared spectral parameter inverse scattering transform perturbation

Explicit Multisoliton Solution to the Coupled Nonlinear Schrodinger Equations

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Wuhan University Journal of Natural Sciences 2013年第4期18卷 319-322页

作者： ZHANG Dong yan tian CAI Hao School of Physics and Technology Wuhan University

Based on the inverse scattering transform for the coupled nonlinear Schrodinger （NLS） equations with vanishing boundary condition （VBC）, the multisoliton solution has been derived by some determinant techniques of some special matrices and determinants, especially the Cauchy-Binet formula. The oneand two-soliton solutions have been given as the illustration of the general formula of the multisoliton solution. Moreover, new nonsymmetric solutions corresponding to different number of zeros of the scattering data on the upper and lower half plane are discussed.

关键词： coupled nonlinear Schrodinger equations multisoliton solution determinant techniques

Influence of different magnetic forces on the effect of colonic anastomosis in rats

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World Journal of Gastrointestinal Surgery 2024年第3期16卷 860-870页

作者： Bo-yan tian Miao-Miao Zhang Jia Ma Yi Lyu Xiao-Peng yan Department of Hepatobiliary Surgery The First Affiliated Hospital of Xi'an Jiaotong UniversityXi'an 710061Shaanxi ProvinceChina National Local Joint Engineering Research Center for Precision Surgery&Regenerative Medicine The First Affiliated Hospital of Xi'an Jiaotong UniversityXi'an 710061Shaanxi ProvinceChina Department of Surgical Oncology Shaanxi Provincial People's HospitalXi'an 710068Shaanxi ProvinceChina

BACKGROUND Despite much work having been conducted on magnetic compression anastomo-sis(MCA)in the digestive tract,there are no reports on the influence of magnetic force on the *** To investigate the effect of different magnetic force magnets on the MCA of the digestive *** Two groups of magnets of the same sizes but different magnetic forces were designed and produced.A total of 24 Sprague-Dawley rats were randomly assigned into two groups(powerful magnet group and common magnet group),with 12 rats in each *** types of magnets were used to complete the colonic side-to-side anastomosis of the *** operation time and magnet discharge time were *** anastomotic specimens were obtained 4 wk after the operation and then the burst pressure and diameter of the anastomosis were measured,and the anastomosis was observed via the naked eye and subjected to histological *** The magnetic forces of the powerful and common magnet groups at zero distance were 8.26 N and 4.10 N,*** colonic side-to-side anastomosis was completed in all 24 rats,and the operation success rate and postoperative survival rate were 100%.No significant difference was noted in the operation time between the two *** magnet discharge time of the powerful magnet group was slightly longer than that of the common magnet group,but the difference was not statistically significant(P=0.513).Furthermore,there was no statistical difference in the burst pressure(P=0.266)or diameter of magnetic anastomosis(P=0.095)between the two *** gross specimens of the two groups showed good anastomotic healing,and histological observation indicated good mucosal continuity without differences on *** In the rat colonic side-to-side MCA model,both the powerful magnet with 8.26 N and the common magnet with 4.10 N showed no significant impact on the anastomosis establishment process or its effect.

关键词： Magnetosurgery Magnetic compression anastomosis Colonic anastomosis Magnetic force Rats

Toxic effect of dinoflagellate Alexandrium species on Cladocera Moina mongolica Daday

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Acta Oceanologica Sinica 2010年第2期29卷 120-126页

作者： yan tian CHEN Taoying ZHOU Mingjiang Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China College of Fisheries and Life Science Shanghai Ocean University Shanghai 201306 China

The main objective of this study was to investigate toxic effects of the dinoflagellate Alexandrium species, on cladocera Moina mongolica in the laboratory. Ten strains of Alexandrium species, including Alexandrium tamarense （AT-6, ATHK, ATCI02, ATCI03 and AT5-1）, A. catenella （ACDH）, A. affine （AC-1 and AS-1）, A. lusitanicum and A A. tamarense （ATHK, ATCI02 and AT5-1） and A minutum were tested. The results showed that affine （AC-1 and AS-1）, but not A. tamarense （AT-6 and ATCI02）, A. catenella （ACDH）, A. lusitanicum and A. minutum had significantly negative effects on the survival of M. mongoliea; when exposed to these ten strains of Alexandrium species in densities of 3 000 cells/cm^3 for 7 d, respecyively. M. mongolica could feed on A. tamarense （AT-6, ATHK, ATCI02, ATCI03 and AT5-1）, A. eatenella, A. lusitanieum and A. minutum, but exhibited little or no grazing on A. affine （AC-1 and AS-1）, based on the changes in gut pigment af- ter exposure to alga for 1 and 12 h. A. affine AC-1, which had the strongest toxicity on the survival of M. mongolica, was chosen to further study the negative effects on M. mongolica. The results showed that the effect of A. affine AC-1 on the survival of M. mongolica was density-dependent, and its lethal effects on one-day, two-day and three-day old M. mongolica were exacerbated with increasing age; The whole algal culture, re-suspended algal cells, cell fragments and cell contents all had adverse impacts on the survival of M. mongolica. Moreover, both juvenile numbers and life-span time of M. mongolica were decreased significantly when they were cultured in A. affine AC-1 of 10 and 50 cells/cm^3, combined with 3×10^6 cells/cm^3 of Chlorella spp., respectively. As a non-PSP producer, A. affine may produce other toxins, responsible for the strong negative effects on M. mongolica.

关键词： red tides Alexandrium species Moina mongolica Daday toxic effect

Stability behavior of the Lanxi ancient flood control levee after reinforcement with upside-down hanging wells and grouting curtain

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Journal of Mountain Science 2024年第1期21卷 84-99页

作者： QIN Zipeng tian yan GAO Siyuan ZHOU Jianfen HE Xiaohui HE Weizhong GAO Jingquan School of Water Conservancy and Environment Engineering Zhejiang University of Water Resources and Electric PowerHangzhou 310018China Department of Civil Engineering Imperial College LondonLondonSW71BFEngland Lanxi Water Affairs Bureau Lanxi 321102China Zhejiang Water Conservancy Engineering Consulting Co. LtdHangzhou 310051China

The stability of the ancient flood control levees is mainly influenced by water level fluctuations, groundwater concentration and rainfalls. This paper takes the Lanxi ancient levee as a research object to study the evolution laws of its seepage, displacement and stability before and after reinforcement with the upside-down hanging wells and grouting curtain through numerical simulation methods combined with experiments and observations. The study results indicate that the filled soil is less affected by water level fluctuations and groundwater concentration after reinforcement. A high groundwater level is detrimental to the levee's long-term stability, and the drainage issues need to be fully considered. The deformation of the reinforced levee is effectively controlled since the fill deformation is mainly borne by the upside-down hanging wells. The safety factors of the levee before reinforcement vary significantly with the water level. The minimum value of the safety factors is 0.886 during the water level decreasing period, indicating a very high risk of the instability. While it reached 1.478 after reinforcement, the stability of the ancient levee is improved by a large margin.

关键词： Stability analysis Multiple factors Antiseepage reinforcement Upside-down hanging well Grouting curtain Ancient levee

Cooperative guidance law based on super-twisting observer for target maneuvering

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Journal of Systems Engineering and Electronics 2024年第5期35卷 1304-1314页

作者： GAO Mengjing yan tian HAN Bingjie CHENG Haoyu FU Wenxing HAN Bo Unmanned System Research Institute Northwestern Polytechnical UniversityXi’an 710072China AVIC Xi’an Aeronautics Computing Technique Research Institute Xi’an 710072China 93525 Troops Shigatse 857000China

To solve the problem that multiple missiles should simultaneously attack unmeasurable maneuvering targets,a guidance law with temporal consistency constraint based on the super-twisting observer is ***,the relative motion equations between multiple missiles and targets are established,and the topological model among multiple agents is ***,based on the temporal consistency constraint,a cooperative guidance law for simultaneous arrival with finite-time convergence is ***,the unknown target maneuver-ing is regarded as bounded *** on the second-order sliding mode theory,a super-twisting sliding mode observer is devised to observe and track the bounded interfer-ence,and the stability of the observer is *** with the existing research,this approach only needs to obtain the sliding mode variable which simplifies the design *** simulation results show that the designed cooperative guidance law for maneuvering targets achieves the expected *** ensures successful cooperative attacks,even when confronted with strong maneuvering targets.

关键词： cooperative guidance super-twisting target maneuver finite time convergence.

Screening for lipophilic marine toxins and their potential producers in coastal waters of Weihai in autumn,2020

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Journal of Oceanology and Limnology 2022年第6期40卷 2218-2230页

作者： Huixia GENG Hongxiao SUN Chao LIU Fanzhou KONG Qingchun ZHANG tian yan Rencheng YU CAS Key Laboratory of Marine Ecology and Environmental Sciences Institute of OceanologyChinese Academy of SciencesQingdao 266071China Laboratory for Marine Ecology and Environmental Science Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China University of Chinese Academy of Sciences Beijing 100049China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China

Lipophilic marine toxins(LMTs)produced by some microalgae in the sea could accumulate in shellfish and pose potential threats to the health of seafood *** and shellfish samples were collected from coastal waters of Weihai in Shandong Peninsula,China in autumn,2020,and screened for lipophilic marine toxins and their potential producers using liquid chromatography-tandem mass spectrometry(LC-MS/MS)analysis and high throughput sequencing of partial DNA(V4 region of the 18S rRNA gene)extracted from ***-2(PTX2),trace amounts of azaspiracid(AZA1 or AZA40),and 13-desmethyl spirolide C(13-DesMe-C)were detected in phytoplankton samples,while PTX2 and gymnodimine(GYM)were detected in shellfish *** toxin content in shellfish samples was much lower than the regulatory limit or values reported *** suggest that lipophilic marine toxins should have low risk in coastal waters of Weihai in *** on the data of high throughput sequencing,the OTUs were assigned to 5 identified species of Alexandrium,including *** capable of producing 13-DesMe-C and *** OTUs were found closely related to the toxic species in genus Dinophysis,but it is impossible to assign them to any identified species due to the low resolving power of the V4 region for *** OTUs could not be assigned to any identified species in the genus Azadinium,suggesting the existence of unidentified species in this region.

关键词： harmful algal blooms phytoplankton shellfish lipophilic marine toxins(LMTs) Yellow Sea liquid chromatography-tandem mass spectrometry

Tempo-spatial distribution of Ulva ***-propagules in the Yellow Sea during and after green tide in 2019

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Journal of Oceanology and Limnology 2022年第6期40卷 2462-2472页

作者： Jin ZHAO Fanzhou KONG Qianchun LIU Fengjie LI Xiu WEI tian yan Peng JIANG CAS and Shandong Province Key Laboratory of Experimental Marine Biology Center for Ocean Mega-ScienceInstitute of OceanologyChinese Academy of SciencesQingdao 266071China Laboratory for Marine Biology and Biotechnology Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China CAS Key Laboratory of Marine Ecology and Environmental Sciences Institute of OceanologyChinese Academy of SciencesQingdao 266071China Laboratory of Marine Ecology and Environmental Science Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China University of Chinese Academy of Sciences Beijing 100049China College of Life Science Qingdao UniversityQingdao 266071China

Large-scale green tides occur frequently in summer in the Yellow Sea in recent ***,providing“seeds”for the seaweeds,play an important role in the formation of green *** studied the distribution pattern and genetic composition of the Ulva micro-propagules in the Yellow Sea during and after the green tide in *** April,a great amount of Ulva micro-propagules was detected in the Subei Shoal,with the average density of 908 inds./L,being similar to that of previous *** was found out at a low percentage(4%),and 25%of them were positive when tested by the specific marker for the floating *** percentage of *** was obviously lower than that in the same season from 2009 to ***,the quantity of *** micro-propagules sharply *** variation in composition of the micro-propagules in Subei radial sand ridges was revealed in the background of the alternation of macroalgal tides in the Yellow Sea in the latest *** the green tide in June and July,Ulva micro-propagules were detected from some nearshore sites where the floating seaweeds distributed,and *** was the dominate *** September,when the green tide ended,no Ulva micro-propagule was detected from the open sea area of the Yellow *** is indicated that the green algae micro-propagules were unlikely to exist in the open water of the Yellow Sea for a long time according to the large-scale *** mechanism of preserving micro-propagules in Subei radial sand ridges,and the destination of *** micro-propagules in the open sea area of the Yellow Sea after green tide deserves further study.

关键词： green tide Ulva prolifera micro-propagule Yellow Sea

Clinical Practice Guidelines and Experts’Consensuses for Treatment of Coronavirus Disease 2019(COVID-19)Patients with Chinese Herbal Medicine:A Systematic Review

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Chinese Journal of Integrative Medicine 2020年第10期26卷 786-793页

作者： LI Yu-xi LI Juan ZHANG Yue tian yan-ping ZHANG Yong-gang JIN Rong-jiang GUO yan Mike Clarke School of Acupuncture-Moxibustion and Tuina Chengdu University of Traditional Chinese MedicineChengdu(610032)China School of Health Preservation and Rehabilitation Chengdu University of Traditionai Chinese MedicineChengdu(610032)China West China Hospital Sichuan UniversityChengdu(610032)China Xiyuan Hospital China Academy of Chinese Medicine SciencesBeijing(100091)China Northern Ireland Clinical Trials Unit and Methodology Hub Centre for Public HealthQueen's University BelfastBelfastUK

Objective:To systematically review the clinical practice guidelines for the treatment of coronavirus disease 2019(COVID-19)patients with Chinese herbal medicine(CHM),summarize their recommendations and evaluate their ***:Electronic databases,websites of governments,academic associations or organizations for eligible guidelines were searched up to April *** were extracted to summarize recommendations for the use of Chinese herbal formulae and Chinese patent medicine(CPM)for COVID-19 *** methodological quality and reporting quality of the included guidelines were independently evaluated,using the Appraisal of Guidelines for REsearch and Evaluation(AGREE)Ⅱtool and Reporting Items for Practice Guidelines in healthcare(RIGHT)statement,***:Totally 45 guidelines were identififi ed:42(93%)suggested specific CM formulae for treating COVID-19 patients;and 35(78%)assigned patients diagnosed with COVID-19 to 4 stages(early,development,critical and recovery).The recommended formulae and CPMs for each stage with diverse syndrome types have been *** of the included guidelines were of low methodological quality,with only one achieving moderate quality of AGREEⅡ.The frequency with which the 35 items in the Reporting Items for Practice Guidelines in Healthcare(RIGHT)checklist were reported averaged 36.5%across the 45 ***:This systematic review has summarized current recommendations for treating COVID-19 patients with CHM and shows that the general quality of present guidelines is quite *** development of future guidelines should include increased awareness of the features of good quality guidelines.

关键词： coronavirus disease 2019 COVID-19 Chinese medicine herbal medicine clinical practice guideline systematic review