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Post-fire habitat restoration of sables during winter season in northern slope of the Great Xing＇an Mountains

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Journal of Forestry Research 2006年第3期17卷 231-237页

作者： XIE Fu-ju LI Xiu-zhen xiao du-ning Hong S. He Institute of Applied Ecology Chinese Academy of Sciences P.O.Box 417 Shenyang 110016 P. R. China Graduate School of the Chinese Academy of Sciences Beijing 100039 P. R. China School of Natural Resources University of Missouri-Columbia Columbia MO 65211-7270 USA

Habitat loss and fragmentation have been associated with the decline of endangered species. In 1987, a catastrophic fire in the northern Great Hing＇an Mountains of China, where the main habitat of sables （Martes zibellina） is located, aggravated the loss and fragmentation of the forest landscape. due to restricted distribution and low population density, sables were listed in the national first-grade protected species in China. The objective of this paper was to identify to what extent the habitat of sables had been restored 13 years after the fire. Based on the behavioral data, which came from field survey information by radio-tracking, GPS （Global Positioning System） and forest inventory data, suitability habitat maps were derived using the Ecological Niche Suitability Model （ENSM）. In addition, the habitat structure was analyzed with selected landscape indices. Although forest cover mostly had been restored by 2000, the results indicated that, compared to the pre-fire situation, the areas of suitable habitat had been reduced significantly, especially those of less suitable, marginally suitable and moderately suitable designation. Fragmentation was aggravated, and suitable patches were found to be further isolated with the exception of those in most suitable areas. The ratio of the patch perimeter to area in unsuitable, moderately suitable and suitable areas decreased, while the ratios within other suitability types increased. Moreover, the percentage of soft boundaries decreased slightly, which can influence the redistribution of sables. The results above indicated that the suitable habitat had deteriorated, and the restoration of the sables＇ habitat remained to be done.

关键词： Suitable habitat Habitat loss Fragmentation Edge effect Habitat restoration.

石羊河流域中下游绿洲土地利用变化与水资源动态研究

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水科学进展 2005年第5期16卷 643-648页

作者：李小玉肖笃宁中国科学院寒区旱区环境与工程研究所甘肃兰州730000

根据1986年和2000年的TM影像数据,利用地理信息系统(GIS)技术通过景观斑块的转移矩阵计算,分析了石羊河流域凉州区和民勤两个典型绿洲近15年来的土地利用变化;并利用不同时期中下游绿洲水资源量和开发利用程度,结合种植业结构,分析了该... 详细信息

根据1986年和2000年的TM影像数据,利用地理信息系统(GIS)技术通过景观斑块的转移矩阵计算,分析了石羊河流域凉州区和民勤两个典型绿洲近15年来的土地利用变化;并利用不同时期中下游绿洲水资源量和开发利用程度,结合种植业结构,分析了该区域水资源利用动态变化。结果表明,耕地大量增加,凉州区和民勤绿洲分别增加了6 302 hm2和36 434 hm2,民勤绿洲林地大面积减少,2000年林地面积仅为1986年的55%,绿洲面积减少了23 365 hm2;而中游凉州区绿洲面积却增加了8 167 hm2;上下游用水量之比从20世纪50年代的1.612急剧增大到90年代的8.33,用水矛盾日益突出,下游水库来水量40年来下降达63.1%;地下水开采强度日益增加,机井分布密集,地下水位大幅度下降;种植业结构不合理,耗水量较大的粮食作物所占的比例过大。

关键词：石羊河土地利用水资源动态变化绿洲

Behavioral fragmentation of waterfowl habitat and its landscape ecological design in Shuangtai-hekou Reserve,Liaoning,China

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Journal of Environmental Sciences 1999年第2期11卷 104-108页

作者： Hu Yuan man, xiao du ning Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110015, China

Behavioral fragmentation of wildlife habitat is discussed. Using “buffer” module in ARC/INFO, behavioral fragmentation habitat of Red crowned crane, Saunders gull, Oriental white stork and Siberian white crane was calculated in the Shuangtai hekou National Reserve, Liaoning Province, China. The result showed that breeding Red crowned crane, Siberian white crane and breeding Saunders gull are very sensitive to fragmentation factors. Suitable habitat is so little for more than 2000 Saunders gull to breed. The reserve only has a capacity of 38 pairs for breeding Red crowed crane. Two key measures were made. First, dismantles all the abandoned oil wells and recovers the original ecosystem to decrease the fragmentation effect, directly benefit to breeding or migration of Red crowned crane and Oriental white stork. Second, recovers the Suaeda tidal mud flat from artificial shrimp and crab pond in the kernel zone of the reserve to enlarge the habitat area of Saunders gull and Siberian white crane.

关键词： behavioral fragmentation waterfowl habitat landscape ecological design.

Core concepts of landscape ecology

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Journal of Environmental Sciences 1999年第2期11卷 4-8页

作者： xiao du ning, Li Xiu zhen Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110015, China

People from different backgrounds may have various opinions and methods dealing with landscape ecology. As a basic ecology theory for decision making in land use planning and resource management, it should provide sound scientific principles, which means some core concepts for landscape ecology need to be established. This paper attempts to introduce some core concepts for landscape ecology, with brief analysis, including: the integrity of landscape system and the heterogeneity of landscape elements; scale in landscape ecology; mosaics of landscape structure; spatial aggregation and spread of ecological flow; physical cultural nature of landscape; the irreversible and human dominated landscape evolution; the multi value of landscape.

关键词： landscape ecology core concept mosaic ecological flow multi value.

Rapid discovery of two unprecedented meroterpenoids from Daphne altaica *** molecular networking integrated with MolNetEnhancer and Network Annotation Propagation

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Chinese Chemical Letters 2024年第8期35卷 294-298页

作者： Wei-Yu Zhou Zi-Han Xi ning-ning du Li Ye Ming-Hao Jiang Jin-Le Hao Bin Lin Guo-Dong Yao xiao-xiao Huang Shao-Jiang Song Key Laboratory of Computational Chemistry-Based Natural Antitumor Drug Research&Development Liaoning ProvinceEngineering Research Center of Natural Medicine Active Molecule Research&DevelopmentLiaoning ProvinceKey Laboratory of Natural Bioactive Compounds Discovery&ModificationShenyangSchool of Traditional Chinese Materia Medic1Shenyang Pharmaceutical UniversityShenyang 110016China Key Laboratory of Structure-Based Drug Design and Discovery of Ministry of Education Shenyang Pharmaceutical UniversityShenyang 110016China Wuya College of Innovation Shenyang Pharmaceutical UniversityShenyang 110016China

Under the guidance of the approach which integrates molecular networking,MolNetEnhancer and Net-work Annotation Propagation(NAP),daphnaltaicanoids A and B(1 and 2)with unprecedented 9-oxa-tetracyclo[6.***.1.0^(2,6).0^(8,13)]pentadecane and tetracyclo[5.***.0.1^(2,5).2^(4,11)]tridecane central frameworks were iso-lated from Daphne altaica Pall.,representing two types of unparalleled meroterpenoid *** struc-tures were elucidated by extensive spectroscopic analysis,nuclear magnetic resonance(NMR)calcula-tions,DP4+analysis and electronic circular dichroism(ECD)*** plausible biosynthetic path-ways for 1 and 2 were ***,2 exerted potent neuroprotective activities which were su-perior to trolox at 12.5 and 25μmol/***,1 and 2 exhibited more noticeable acetylcholinesterase inhibitory activities than *** docking simulations were performed to explore the inter-molecular interaction of compounds 1 and 2 with *** bioactivity evaluation results highlight the prospects of 1 and 2 as a novel category of neurological agents.

关键词： Daphne altaica Pall. Molecular networking MolNetEnhancer NAP Unprecedented meroterpenoid frameworks Neuroprotective activities Acetylcholinesterase inhibitors

SPATIAL PATTERN AND FUNCTION OF CORRIDORS IN WETLANDS OF LIAOHE DELTA

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Chinese Geographical Science 2000年第2期10卷 177-181页

作者： WANG Xian-li LI Xiu-zhen xiao du-ning(Institute of Applied Ecology the Chinese Academy of Sicnces, Shenyang 110015, P R. China) Institute of Applied Ecology the Chinese Academy of Sciences Shenyang P. R. China

Corridors are special patches with narrow and long shape, and often have the functions as transportation,protection, resources and aesthetics. Corridors in the study area can be classilied into 8 types, with a total length of 5167. 2 km, and conidor density of 1. 25 km/km2. The conidore are mainly composed of irrigation and drainag canals,the total length of which is 2794 km,about 54. 1% of all the corridors. The conidors have segmented the landscape, and changed the original situation of the natural landscapes. The types of conidors are clooely related to the landscape types they are distributed in. Canals are maily distributed in the wetland landscapes, while roads are mainly in the built-up area. Dikes are always along rivers or coastlines. The conidors are most densely distributed wherever human activity occurs most bouendy, such as in the artifical wedlands of paddy fields.

关键词： corridor Liaohe delta landscape ecology

Current understanding of ELF4 deficiency:a novel inborn error of immunity

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World Journal of Pediatrics 2024年第5期20卷 444-450页

作者： Hong-Qiang du xiao-Dong Zhao Department of Rheumatology&Immunology National Clinical Research Center for Child Health and DisordersMinistry of Education Key Laboratory of Child Development and DisordersChongqing Key Laboratory of Child Rare Diseases in Infection and ImmunityChildren’s Hospital of Chongqing Medical UniversityZhongshan Er Road 136Yuzhong DistrictChongqingChina

Background ELF4 deficiency has been recently recognized as a novel disorder within the spectrum of inborn errors of immunity(IEIs),specifically categorized as a“disease of immune dysregulation.”Cases of this condition,reported by our team and others,are very limited *** such,our current knowledge of this new disease remains *** review aims to provide a brief overview of the clinical manifestations,pathogenesis,and treatment strategies for this novel *** sources A comprehensive review was conducted after an extensive literature search in the PubMed/Medline database and websites concerning transcriptional factor ELF4 and reports concerning patients with ELF4 *** search strategy was“ELF4 OR ETS-related transcription factor Elf-4 OR EL4-like factor 4 OR myeloid Elf-1-like factor”as of the time of manuscript *** The current signature manifestations of ELF4 deficiency disorder are recurrent and prolonged oral ulcer,abdominal pain,and diarrhea in pediatric *** some cases,immunodeficiency and autoimmunity can also be *** Sanger sequencing or whole exome sequencing can be used to detect variation in ELF4 *** blotting for ELF4 expression of the patient’s cells can confirm the pathogenic effect of the *** fully confirm the pathogenicity of the variant,further functional test is strongly *** and biologics are the mainstream management of ELF4 deficiency *** Pediatric males presenting with recurring ulcerations in digestive tract epithelium with or without recurrent fever should be suspected of *** atypical presentations are prominent,variations in ELF4 gene should be carefully evaluated functionally due to the complex nature of ELF4 *** of treating DEX includes use of glucocorticoid and biologics and more precise treatment needs more patients to identify and further mechanistic study.

关键词： ELF4 transcription factor Immune dysregulation Inborn errors of immunity Mechanism Recurrent infections

Effect of spatial pattern on nutrient reduction in the Liaohe Delta

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Journal of Geographical Sciences 2001年第3期11卷 336-349页

作者： LI Xiu-zhen, xiao du-ning, HU Yuan-man, WANG Xian-li (Institute of Applied Ecology, CAS, Shenyang 110016, China) Institute of Applied Ecology CAS

The effect of spatial pattern on the nutrient reduction is investigated based on the spatial simulation model developed for the study area of the Liaohe Delta, China. Four scenarios are designed to test the effect of different landscape components on the nutrient reduction in the reed marsh: Canal density, reed area size, reed area shrinking pattern, and pumping station position. Based on a spatial model designed for the study area, the nutrient reduction in each case of these scenarios is simulated. The results indicate that each factor brings less than 10% change in the total nutrient reduction rate. More canals will not help much to improve nutrient reduction. Smaller areas are more efficient than larger ones. The shrinkage pattern is better than others in keeping a higher nutrient reduction rate. It is also more efficient to keep the pumping station near the border of the area to be irrigated. These conclusions provide theoretical supports to strategy makers for local land use planning, and contribute to the understanding of the relationship between landscape patterns and functions.

关键词： pattern effect nutrient reduction wetland canal density area size shrinking pattern pumping station position

Constructing Built-In Electric Fields with Semiconductor Junctions and Schottky Junctions Based on Mo-MXene/Mo-Metal Sulfides for Electromagnetic Response

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Nano-Micro Letters 2024年第10期16卷 453-473页

作者： xiaojun Zeng xiao Jiang Ya ning Yanfeng Gao Renchao Che School of Materials Science and Engineering Jingdezhen Ceramic UniversityJingdezhen 333403People's Republic of China School of Materials Science and Engineering Shanghai UniversityShanghai 200444People's Republic of China Laboratory of Advanced Materials Shanghai Key Lab of Molecular Catalysis and Innovative MaterialsAcademy for Engineering and TechnologyFudan UniversityShanghai 200438People's Republic of China Zhejiang Laboratory Hangzhou 311100People's Republic of China

The exploration of novel multivariate heterostructures has emerged as a pivotal strategy for developing high-performance electromagnetic wave(EMW)absorption ***,the loss mechanism in traditional heterostructures is relatively simple,guided by empirical observations,and is not *** this work,we presented a novel semiconductor-semiconductor-metal heterostructure sys-tem,Mo-MXene/Mo-metal sulfides(metal=Sn,Fe,Mn,Co,Ni,Zn,and Cu),including semiconductor junctions and Mott-Schottky *** skillfully combining these distinct functional components(Mo-MXene,MoS_(2),metal sulfides),we can engineer a multiple heterogeneous interface with superior absorption capabilities,broad effective absorption bandwidths,and ultrathin matching *** successful establishment of semiconductor-semiconductor-metal heterostructures gives rise to a built-in electric field that intensifies electron transfer,as confirmed by density functional theory,which collaborates with multiple dielectric polarization mechanisms to substantially amplify EMW *** detailed a successful synthesis of a series of Mo-MXene/Mo-metal sulfides featuring both semiconductor-semiconductor and semiconductor-metal *** achievements were most pronounced in Mo-MXene/Mo-Sn sulfide,which achieved remarkable reflection loss values of-70.6 dB at a matching thickness of only 1.885 *** cross-section calculations indicate that these MXene/Mo-metal sulfides have tremendous potential in practical military stealth *** work marks a departure from conventional component design limitations and presents a novel pathway for the creation of advanced MXene-based composites with potent EMW absorption capabilities.

关键词： Semiconductor-semiconductor-metal heterostructure Semiconductor junctions Mott-Schottky junctions Built-in electric field Electromagnetic wave absorption