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Characteristics of soil erosion and sediment size distribution for different land uses in the Chinese Mollisol region

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Journal of Mountain Science 2021年第5期18卷 1295-1306页

作者： SHEN Hai-ou FENG Jun WANG Dong-li li hong-li WANG Yu College of Resources and Environment Jilin Agricultural UniversityChangchun 130118China College of Environmental Science and Engineering Liaoning Technical UniversityFuxin 123000China

Soil erosion is currently a major contributor to the degradation of global soil *** characteristics of sediment size distribution affect soil erosion ***,few studies have quantitatively explored soil erosion processes and sediment size distributions on natural hillslopes for different land uses,especially in the Chinese Mollisol *** objective of this study was to investigate the impacts of land uses(corn,fallow,buffer strip and bare hillslopes)under 5°and 10°slope gradients on total runoff,runoff rates,soil losses,sediment concentration processes,and sediment size *** runoff plots(20 m long and 5 m wide)were subjected to inflow scour experiments(1 L min–1 m–2,lasting 40 min).The results showed that the total runoff varied from 2.62 to 6.40 L m–2 and from 8.36 to 20.39 L m–2 on hillslopes at 5°and 10°,*** changes in runoff rates versus run time exhibited gradual increasing trends at 5°,but exhibited initial rapidly increasing trends and then relatively stable trends at 10°.Fallow hillslopes produced the lowest soil losses,which were 45.34%-45.92%,2.74%-6.72%and 1.68%-3.44%for the corn,buffer strip and bare hillslopes,*** sediment concentrations were very small and stabilized between 0.5-2.0 g L–1 on the fallow hillslopes and 1.5-3.0 g L–1 on the corn hillslopes at 5°,but the changing trends in sediment concentration versus run time for the four land uses generally decreased at 10°.Furthermore,it was demonstrated that the proportion of sediment<0.25 mm was the largest in comparison with the other sediment size fractions,and<0.25 mm soil particles and aggregates played a dominant role in soil aggregate loss under different land ***,protecting these precious soil particles and aggregates by applying proper soil conservation measures especially for the relatively gentle hillslopes was particularly ***,the fallow hillslope with greater soil and water conservation capacitie

关键词： Field plot Runoff Sediment size Simulation Soil loss

Cerebral venous sinus thrombosis following transsphenoidal surgery for craniopharyngioma:A case report

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World Journal of Clinical Cases 2020年第6期8卷 1158-1163页

作者： Tao Chang Yan-Long Yang li Gao li-hong li Department of Emergency Medicine Second Affiliated Hospital of Air Force Medical UniversityXi’an 710038Shaanxi ProvinceChina Department of Neurosurgery Second Affiliated Hospital of Air Force Medical UniversityXi’an 710038Shaanxi ProvinceChina

BACKGROUND Cerebral venous sinus thrombosis(CVST)is a rare condition in patients with craniopharyngioma following transsphenoidal *** SUMMARY A 56-year-old man who underwent transsphenoidal surgery for craniopharyngioma 26 d ago presented gradual headache and cerebrospinal fluid leakage while vomiting 5 d post-discharge and required readmission to our department of *** admission,head imaging examination showed a hyperdense shadow in the superior sagittal sinus and right transverse sinus,edema at the bilateral parietal lobe,and hemorrhage at the left parietal lobe and right occipital lobe;the venous phase of cerebral angiography revealed *** patient was treated immediately by intravenous thrombolysis,endovascular thrombolysis,and mechanical thrombectomy after the definite ***,the neurological status of the patient continued to deteriorate and he died on the fourth day after *** For craniopharyngioma undergoing transsphenoidal surgery,it is vital to take an effective strategy to manage the postoperative complications,such as diabetes insipidus,severe electrolyte imbalance,and cerebrospinal fluid ***,the early differential diagnosis of CVST is essential when it develops clinical symptoms,especially in patients following transsphenoidal surgery with a high risk of ***,the timely and effective treatment of the CVST is critical for preventing neurological deterioration.

关键词： Craniopharyngioma Transsphenoidal surgery Cerebral venous sinus thrombosis Case report

Evaluation of Impact of Major Causes of Death on life Expectancy Changes in China,1990-2005

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Biomedical and Environmental Sciences 2009年第5期22卷 430-441页

作者： YAN-hong WANG li-MING li Department of Epidemiology&Biostatistics School of Public HealthPeking University Health Science CenterBeijing 100191China

Objective To evaluate the impact of major causes of death on changes of life expectancy in China. Methods life expectancy was calculated by standard life table techniques using mortality data from the national censuses in 1990 and 2000 and the 1% National Population Sampling Surveys in 1995 and 2005, Mortality data about the major causes of death from VR-MOH were used as reference values to estimate their death proportions of the specific age groups by sex and regions, as well as all-cause mortality and age-specific mortality rates of major causes of death. Decomposition method was used to quantitatively evaluate the impact. Results Three key findings were identified in our study. First, China's health challenge was shifted from diseases related to living conditions to those related to behavior and lifestyle, with rural areas relatively lagged behind urban areas, Second, the impacts of cardiovascular diseases and neoplasm on the middle aged and elderly population were stressed. Third, compared to the urban population, the rural population tended to have increasing mortality of neoplasm and cardiovascular diseases, especially in adults at the age of 15-39 years. Conclusion Further efforts should be made to reduce the incidence of neoplasm and cardiovascular diseases, especially in rural areas, by promoting healthy behavior and lifestyle and providing appropriate therapies for all patients in need.

关键词： China life expectancy Cardiovascular disease Neoplasm

Observer-based Adaptive Iterative Learning Control for Nonlinear Systems with Time-varying Delays

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International Journal of Automation and computing 2010年第4期7卷 438-446页

作者： Wei-Sheng Chen Rui-hong li Jing li Department of Applied Mathematics Xidian University X{an 710071 PRC

An observer-based adaptive iterative learning control （AILC） scheme is developed for a class of nonlinear systems with unknown time-varying parameters and unknown time-varying delays. The linear matrix inequality （LMI） method is employed to design the nonlinear observer. The designed controller contains a proportional-integral-derivative （PID） feedback term in time domain. The learning law of unknown constant parameter is differential-difference-type, and the learning law of unknown time-varying parameter is difference-type. It is assumed that the unknown delay-dependent uncertainty is nonlinearly parameterized. By constructing a Lyapunov-Krasovskii-like composite energy function （CEF）, we prove the boundedness of all closed-loop signals and the convergence of tracking error. A simulation example is provided to illustrate the effectiveness of the control algorithm proposed in this paper.

关键词： Adaptive iterative learning control (AILC) nonlinearly parameterized systems time-varying delays Lyapunov- Krasovskii-like composite energy function.

Preparation of High Selective Molecularly Imprinted Polymers for (S)-4-Phenyl-2-oxazolidinone

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Chinese Chemical Letters 2006年第12期17卷 1551-1554页

作者： Yong LUO Lan liU li hong li Qin Ying DENG School of Chemistry and Chemical Engineering Sun Yat-Sen University Guangzhou 510275

（S）-4-Phenyl-2-oxazolidinone imprinted polymers were prepared by using methacrylic acid （MAA） as the functional monomer, and divinylbenzene （DVB） as crosslinker. The factors, which influence the selectivity of the polymers were explored. Effective separation was observed for racemic 4-phenyl-2-oxazolidinone in mobile phase of acetonitrile. The investigation of mobile phase suggested that the hydrogen bonds between template and functional monomer was a primary factor in chiral recognition, while the preparation of polymers implied that the л-л stacking interaction between template and crosslinker played a role in imprinting procedure.

关键词： Molecularly imprinted polymers (MIPs) 4-phenyl-2-oxazolidinone HPLC.

Nitrogen addition increased resistance of resident plant community to Solidago canadensis invasion by altering allelopathic effect

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Journal of Plant Ecology 2024年第2期17卷 110-121页

作者： Jing-Fang Cai Kai Sun lin li Si-Ha A Yi-Luan Shen hong-li li School of Ecology and Nature Conservation Beijing Forestry UniversityBeijing 100083China The Key Laboratory of EcologicalProtection in the Yellow River Basin of National Forestry and Grassland Administration Beijing Forestry UniversityBeijing 100083China

Allelopathy plays an important role in the interaction between invasive and resident *** nitrogen(N)deposition has become a global problem,but it is unclear whether N enrichment affects the interaction between invasive and resident plants by affecting their ***,we performed a greenhouse experiment in which the resident plant community was grown under two levels of invasion by ***(invasion *** invasion)and fully crossed with two levels of allelopathy(with or without adding activated carbon)and two levels of N addition(with or without).The resident plant communities were constructed with eight herbaceous species that often co-occur with *** results showed that both allelopathy of *** and the resident plants had obvious positive effects on their own *** addition had more obvious positive effects on the resident plants under invasion than those that were not ***,N addition also altered the allelopathy of resident ***,N addition improved the allelopathy of resident plants when they were invaded but decreased the allelopathy of resident plants when they grew *** nitrogen addition had no obvious effect on ***,it reduced the allelopathy of *** results suggest that N addition could improve the resistance of resident plants to invasion by improving the allelopathy of resident plants and reducing the allelopathy of *** fndings provide a scientifc basis to manage and control the *** invasion.

关键词： allelochemicals biological invasion nutrient input nitrogen addition resident plants Solidago canadensis

Does hydrological fluctuation alter impacts of species richness on biomass in wetland plant communities?

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Journal of Plant Ecology 2016年第4期9卷 434-441页

作者： Fang-li Luo Xing-Xing Jiang hong-li li Fei-Hai Yu School of Nature Conservation Beijing Forestry UniversityBeijing 100083China

Aims The diversity-productivity relationship is one of the most critical questions in ecology and can be altered by environmental *** fluctuation affects growth of wetland plants,and such effects vary with plant ***,we hypothesized that hydrological fluctuation changes effects of species richness on productivity of wetland plant *** We constructed wetland plant communities consisting of three or six wetland plant species and subjected them to hydrological fluctuation(*** changing water level)of two frequencies and two ranges,with unchanged water level as the *** measured height,root and shoot dry mass of each plant at *** Findings Hydrological fluctuation significantly decreased biomass of wetland plant communities,which was due to impacts of fluctuation range,but not those of fluctuation *** biomass was significantly higher when species richness was higher,and such an effect did not depend on hydrological ***,hydrological fluctuation can decrease the productivity of wetland plant communities but may not alter the diversity-productivity relationship.

关键词： diversity effects diversity-productivity relationship experimental plant communities flooding fluctuation frequency fluctuation range water depth change

A delayed predator-prey system with impulsive diffusion between two patches

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International Journal of Biomathematics 2017年第1期10卷 175-194页

作者： hong-li li Long Zhang Zhi-Dong Teng Yao-lin Jiang College of Mathematics and System SciencesXinjiang University Urumqi 830046 P. R. China

In most models of population dynamics, diffusion between two patches is assumed to be either continuous or discrete. However, in the real world, it is often the case that diffusion occurs at certain moment every year, impulsive diffusion can provide a more suitable manner to model the actual dispersal （or migration） behaviors for many eco- logical species. In addition, it is generally recognized that some kinds of time delays are inevitable in population interactions. In view of these facts, a delayed predator-prey system with impulsive diffusion between two patches is proposed. By using compari- son theorem of impulsive differential equation and some analysis techniques, criteria on the global attractivity of predator-extinction periodic solution are established, sufficient conditions for the permanence of system are obtained. Finally, numerical simulations are presented to illustrate our theoretical results.

关键词： Predator-prey delay impulsive diffusion global attractivity permanence.

New bisabolane-type phenolic sesquiterpenoids from the marine sponge Plakortis simplex

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Chinese Journal of Natural Medicines 2021年第8期19卷 626-631页

作者： WANG Jie liU li hong li-li ZHAN Kai-Xuan liN Zheng-Jiang JIAO Wei-Hua liN Hou-Wen School of Food and Pharmacy Zhejiang Ocean UniversityZhoushan 316000China Research Center for Marine Drugs State Key Laboratory of Oncogenes and Related GenesDepartment of PharmacyRen Ji HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai 200127China Key Laboratory of Ministry of Education for TCM Viscera-State Theory and Applications Liaoning University of Traditional Chinese MedicineShenyang 110847China

Six new bisabolane-type phenolic sesquiterpenoids,including plakordiols A-D(1-4),(7 R,10 R)-hydroxycurcudiol(5)and(7 R,10 S)-hydroxycurcudiol(6)were isolated from the marine sponge Plakortis simplex collected from the South China *** structures were determined based on extensive analysis of spectroscopic *** configurations were assigned by coupling constant analysis,NOESY correlations,and the modified Mosher’s ***,their cytotoxic and antibacterial activities were evaluated.

关键词： Marine sponge Plakortis simplex Sesquiterpene phenols Plakordiols