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lie Symmetry and Conserved Quantities for Mechanical-Electrical Systems

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Communications in Theoretical Physics 2008年第6期49卷 1417-1420页

作者： JING hong-Xing li yuan-Cheng College of Physics Science and Technology China University of Petroleum （East China） Dongying 257061 China

In this paper, we study lie symmetry and conserved quantities for a mechanical-electrical system. The criterion of the lie symmetry for this system is given. The generalized Hojman conserved quantity and generalized Lutzky conserved quantity deduced from the lie symmetry for the system are obtained. An example is presented to illustrate the results.

关键词： mechanical-electrical system lie symmetry generalized Hojman conserved quantity, generalized Lutzky conserved quantity

Mei Symmetry and Lutzky Conserved Quantity for Nonholonomic Mechanical System with Unilateral Constraints

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Communications in Theoretical Physics 2008年第3期49卷 575-578页

作者： JING hong-Xing li yuan-Cheng College of Physics Science and Technology China University of Petroleum （East China） Dongying 257061 China

In this paper, we study the Mei symmetry which can result in a Lutzky conserved quantity for nonholonomic mechanical system with unilateral constraints. The definition and the criterion of the Mei symmetry for the system are given. The necessary and sufficient condition under which the Mei symmetry is a lie symmetry for the system is obtained. A Lutzky conserved quantity deduced from the Mei symmetry is gotten. An example is given to illustrate the application of our results.

关键词： nonholonomic mechanical system unilateral constraint Mei symmetry Lutzky conserved quantity

lie Symmetry and Generalized Mei Conserved Quantity for Nonconservative Dynamical System

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Communications in Theoretical Physics 2008年第5期49卷 1148-1150页

作者： JING hong-Xing li yuan-Cheng College of Physical Science and Technology China University of Petroleum （East China） Dongying 257061 China

Based on the total time derivative along the trajectory of the system, for noneonservative dynamical system, the generalized Mei conserved quantity indirectly deduced from the lie symmetry of the system is studied. Firstly, the lie symmetry of the system is given. Then, the necessary and sumeient condition under which the lie symmetry is a Mei symmetry is presented and the generalized Mei conserved quantity indirectly deduced from the lie symmetry of the system is obtained. Lastly, an example is given to illustrate the application of the result.

关键词： lie symmetry Mei symmetry generalized Mei conserved quantity nonconservative dynamicalsystem

Changes in global land surface frozen ground and freeze-thaw processes during 1950-2020 based on ERA5-Land data

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Advances in Climate Change Research 2024年第2期15卷 265-274页

作者： Yong YANG Ren-Sheng CHEN Yong-Jian DING hong-yuan li Zhang-Wen liU Qilian Alpine Ecology and Hydrology Research Station Key Laboratory of Ecological Safety and Sustainable Development in Arid LandsNorthwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 73000China State Key Laboratory of Cryospheric Sciences Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 73000China Shandong Provincial Key Laboratory of Water and Soil Conservation and Environmental Protection College of Resources and EnvironmentLinyi UniversityLinyi 276000China

Frozen ground(FG)plays an important role in global and regional climates and environments through changes in land freeze-thaw processes,which have been conducted mainly in different ***,the changes in land surface freeze-thaw processes under climate change on a global scale are still *** on ERA5-Land hourly land skin temperature data,this study evaluated changes in the global FG area,global land surface first freeze date(FFD),last freeze date(LFD)and frost-free period(FFP)from 1950 to *** results show that the current FG areas(1991-2020 mean)in the Northern Hemisphere(NH),Southern Hemisphere(SH),and globe are 68.50×10^(6),9.03×10^(6),and 77.53×10^(6)km^(2),which account for 72.4%,26.8%,and 60.4%of the exposed land(excluding glaciers,ice sheets,and water bodies)in the NH,SH and the globe,respectively;further,relative to 1951-1980,the FG area decreased by 1.9%,8.8%,and 2.8%,*** FG at lower latitudes degrades to intermittently FG,and intermittently FG degrades to non-frozen ground,which caused the global FG boundary to retreat to higher latitudes from 1950 to *** annual FG areas in the NH,SH,and globe all show significant decreasing trends(p<0.05)from 1950 to 2020 at-0.32×10^(6),-0.22×10^(6),and-0.54×10^(6)km^(2)per decade,*** FFP prolongation in the NH is mainly influenced by LFD advance,while in the SH it is mainly controlled by FFD *** prolongation trend of FFP in the NH(1.34 d per decade)is larger than that in the SH(1.15 d per decade).

关键词： Frozen ground Freeze-thaw processes Frost-free period First freeze date Global warming

Quorum sensing inhibition of hordenine analogs on Pseudomonas aeruginosa and Serratia marcescens

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Synthetic and Systems Biotechnology 2021年第4期6卷 360-368页

作者： Yue liu Jun-Jian li hong-yuan li Shi-Ming Deng Ai-Qun Jia School of Pharmaceutical Sciences Key Laboratory of Ministry of Education for Advanced Materials in Tropical Island ResourcesHainan UniversityHaikou570228China

Quorum sensing(QS)plays an essential role in virulence factor production,biofilm formation,and antimicrobial *** a potent QS inhibitor,hordenine can inhibit both QS and biofilm formation in Pseudomonas aeruginosa and Serratia *** this work,we tested the QS inhibitory potential of 27 hordenine analogs against QS and biofilm formation in *** and *** the tested analogs,seven(12,28,27,26,2,23,and 7)exhibited strong QS inhibitory activity against ***,five of which(12,28,27,26,and 2)showed better inhibitory activity than *** addition,seven analogs(28,12,23,7,26,2,and 27)exhibited better biofilm inhibition against *** than *** analogs(7,28,2,and 12)showed QS inhibitory activity against ***,two of which(7 and 28)demonstrated better inhibitory activity than ***,analog 7 showed similar biofilm inhibition against *** as ***-activity relationship(SAR)analysis indicated that the inhibitory activities of the analogs were related to four factors,i.e.,carbon chain length,presence or absence of anα,β-C=C bond,amino group with/without lipophilic group,such as methyl group,and hydroxyl group in benzene ring.

关键词： Hordenine analogs Pseudomonas aeruginosa Serratia marcescens Quorum sensing inhibition QSAR Biofilm

Repair of posterior ventricular septal rupture by right atrial approach

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Journal of Geriatric Cardiology 2023年第12期20卷 886-889页

作者： Shan-Qing BAO Teng-Long WANG yuan-hong li Cheng-Xin ZHANG Department of Cardiovascular Surgery First Affiliated Hospital of Anhui Medical UniversityHefeiChina

Ventricular septal rupture(VSR)is a serious complication that may occur after myocardial infarction(MI).[1]If left untreated,it will lead to high morbidity and *** several surgical interventions have been developed,mortality and complications associated with surgical management are still high,especially in terms of transventricular approaches.[2]

关键词： rupture mortality ventricular

SOliD CYSTIC PAPILLARY TUMOR OF PANCREAS IN EIGHT CHILDREN

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Chinese Medical Sciences Journal 2007年第1期22卷 54-57页

作者： Ke-ren Zhang Hui-min Jia hong Shu Xin-yuan li Department of Pediatric Surgery the Second Affiliated Hospital China Medical University Shenyang 110004

Objective To estimate the clinical and pathological features of pancreatic solid cystic papillary tumor (SCPT) in children. Methods From 2000 to 2005, 8 cases with SCPT of the pancreas were analyzed retrospectively. All cases but one were females. Average age was 12.8 years. By case review, we discussed the clinical and pathological features of SCPT in children. Results The chief complains were abdominal pain and palpable mass. There were 3 cases in the head, 1 case in the body, and 4 cases in the tail of pancreas. The procedures employed included local resection (1 case), distal pancreatectomy (5 cases), pancreaticoduodenectomy (1 case), and biopsy (1 case). Histological examination showed solid with cystic areas and papillary protrusions in the 8 cases; as for immunohistochemical examinations, the positive rate was 100% for α-antitrypsin (AACT), 87.5% for vinmentin, and 62.5% for neuron-specific enolase (NSE). The patients were followed up for 2 months to 4 years but one was lost by follow-up and all were alive postoperatively. SCPT in 2 cases relapsed. Conclusion Occurring predominantly in young females, SCPT is usually curable by surgical resection with a favorable prognosis.

关键词： pancreatic neoplasms pathology therapy prognosis children

From Waste Materials Skin-Friendly Nanostructured Products to Save Humans and the Environment

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Journal of Cosmetics, Dermatological Sciences and Applications 2011年第3期1卷 99-105页

作者： Pierfrancesco Morganti yuan-hong li University of Naples China Medical University R & D Centre of Nanoscience Mavi Sud s. r. l. Department of Dermatology No. 1 Hospital of China Medical University

Waste material from the fishing industry disposed off-shore exceeds 250 billion tons/year, and it is considered hazardous due to its high perishability and polluting effect, both on land and sea. Considering the actual production of chitin, chitosan and oligosaccharides from crustaceons, it is understandable how difficult it is to eliminate all the waste material obtained from food industry, therefore the need for more innovation and creativity. With this in mind we propose an industrial use of the natural chitin nanocrystals (known as chitin-nanofibrils-CN) to produce innovative cosmetics, food supplements and protective films that can improve our way of living while saving the environment.

关键词： Waste Chitin Chitin Nanofibrils

Study on the causes of local recurrence of rectal cancer after curative resection: analysis of 213 cases

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World Journal of Gastroenterology 1998年第6期4卷 72-74页

作者： yuan hong Yin, li Yan, YANG Guo liang, BEI De Jiao and WANG Kun

AIM To study the local recurrent rate and the causes of rectal cancer after surgery. METHODS The clinicopathological data of 213 rectal cancer patients and the follow up information were analyzed. The overall recurrent rate and the recurrent rates from different surgical appreaches were calculated. The main causes of recurrence were investigated. RESULTS Among the 213 cases, 73 (34 27%) had local recurrence. The recurrent time ranged from 3 months to 62 months after the first operation. Most of the recurrence ( 65/73 , 89 04%) occurred within 3 years after operation. CONCLUSION Local recurrence had no significant correlation with surgical methods or pathological types, but closely related to Dukes′ stages, location of primary tumors and the length of the distal rectum resected. Early resection and a wide tumor free resection margin are key factors to prevent local recurrence.

关键词： rectal neoplasms/surgery Rectal neoplasms/pathology Neoplasm recurrent, local