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Boundedness of Maximal Operators and Potential Operators on Carleson Curves in Lebesgue Spaces with Variable Exponent

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Acta Mathematica Sinica,English Series 2008年第11期24卷 1775-1800页

作者： V.KOKILASHVILI S.SAMKO A. Razmadze Mathematical institute International Black Sea University Georgia University of Algarve Portugal

We prove the boundedness of the maximal operator Mr in the spaces L^p（·）（Г,p） with variable exponent p（t） and power weight p on an arbitrary Carleson curve under the assumption that p（t） satisfies the log-condition on Г. We prove also weighted Sobolev type L^p（·）（Г, p） → L^q（·）（Г, p）-theorem for potential operators on Carleson curves.

关键词： weighted generalized Lebesgue spaces variable exponent singular operator fractional integrals Sobolev theorem

Bacterial Community Structure in a Mollisol Under Long-Term Natural Restoration, Cropping, and Bare Fallow History Estimated by PCR-DGGE

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Pedosphere 2009年第2期19卷 156-165页

作者： WANG Guang-Hua JIN Jian LIU Jun-Jie CHEN Xue-Li LIU Ju-Dong LIU Xiao-Bing Key Laboratory of black Soil Ecology Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Harbin 150081 China

Soil microbial biomass and community structures are commonly used as indicators for soil quality and fertility. A investigation was performed to study the effects of long-term natural restoration, cropping, and bare fallow managements on the soil microbial biomass and bacterial community structures in depths of 0-10, 20 30, and 40-50 cm in a black soil （Mollisol）. Microbial biomass was estimated from chloroform fumigation-extraction, and bacterial community structures were determined by analysis of 16S rDNA using polymerase chain reaction-denaturing gradient gel electrophoresis （PCR- DGGE）. Experimental results showed that microbial biomass significantly declined with soil depth in the managements of restoration and cropping, but not in the bare fallow. DGGE profiles indicated that the band number in top 0-10 cm soils was less than that in depth of 20-30 or 40-50 cm. These suggested that the microbial population was high but the bacterial community structure was simple in the topsoil. Cluster and principle component analysis based on DGGE banding patterns showed that the bacterial community structure was affected by soil depth more primarily than by managements, and the succession of bacterial community as increase of soil depth has a similar tendency in the three managements. Fourteen predominating DGGE bands were excised and sequenced, in which 6 bands were identified as the taxa of Verrueomicrobia, 2 bands as Actinobacteria, 2 bands as α-Proteobacteria, and the other 4 bands as 8-Proteobacteria, Aeidobacteria, Nitrospira, and unclassified bacteria. In addition, the sequences of 11 DGGE bands were closely related to uncultured bacteria. Thus, the bacterial community structure in black soil was stable, and the predominating bacterial groups were uncultured.

关键词： bacterial community black soil denaturing gradient gel electrophoresis (DGGE) polymerase chain reaction (PCR) soil depth

Construction of EGFP-tagged rBCG of *** and distribution in chickens

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Science China(Life Sciences) 2009年第3期52卷 278-283页

作者： WANG QiuYue1,LI JianHua1,ZHANG XiChen1,LIU ChengWu2,CAO LiLi1,REN KeYan3,GONG PengTao1,CAI YaNan11 College of Animal Science and Veterinary Medicine,Jilin University,Changchun 130062,China 2 Shenyang Police dog Training School,Shenyang 110034,China 3 Veterinary Science institute of Jilin Province,Changchun 130062,China College of Animal Science and Veterinary Medicine Jilin University Changchun China Shenyang Police dog Training School Shenyang China Veterinary Science institute of Jilin Province Changchun China

Chicken coccidiosis is a major parasitic disease with substantial economic burden to the poultry *** green fluorescent protein(EGFP) tagged recombinant Bacille Calmette-Guerin(rBCG),as a fusion protein with coccidian rhomboid antigen was constructed to track rBCG in vivo in chickens in this *** of chickens with one dose of rBCG pMV361-Rho/EGFP induced humoral immune *** colonization of rBCG in liver,spleen,lung,kidney and caecum was observed by laser confocal ***-time quantitative RT-PCR showed a rise expression level of rhomboid protein on the 7th day and a peak on the 14th day and disappearance on the 28th day after *** results have significant implications for the development of rBCG vaccines against avian coccidiosis.

关键词： coccidiosis rBCG EGFP rhomboid laser confocal microscopy real-time RT-PCR

Locomotor kinematics of the gecko(Tokay gecko) upon challenge with various inclines

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Chinese Science Bulletin 2014年第33期59卷 4568-4577页

作者： Zhou-Yi Wang Ai-Hong Ji Thomas Endlein Wei Li Diana Samuel Zhen-Dong Dai institute of Bio-inspired Structure and Surface Engineering Nanjing University of Aeronautics and Astronautics Centre for Cell Engineering Joseph Black BuildingGlasgow University

Tokay geckos are skillful climbers and are able to negotiate difficult terrain such as steep slopes and overhanging inclines without losing their foothold. Here,we present data on the changes in locomotor kinematics when geckos are challenged to walk on various inclined surfaces. We trained individual geckos to move along a platform which can be tilted to simulate different *** animals were filmed using a high-speed video *** results showed that their speed decreased with increasing slope angle, and their speed on the steep and inverted slopes(sloped angle >60°) decreased at a faster rate than on the shallow slopes(sloped angle<60°). The geckos' stride length was much greater on the shallow slopes compared to the inverted slopes. The influence of stride length and stride frequency on speed was different when the geckos moved across different slopes. There are significant differences duty factor, which varied from 0.54 when wall climbing(90° slope) to 0.84 when walking on the ceiling(180° slope). The mechanisms revealed this study will improve our understanding of control strategies in kinematics and inspire the design of robots with greater mobility.

关键词：运动数据大壁虎倾斜角度高速摄像机速度比占空因数控制策略坡度

Experimental Research on Wave Transmission over Submerged Rubble-Mound Breakwaters

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China Ocean Engineering 2008年第4期22卷 575-584页

作者：左其华 Valeri PENCHEV 李鹏 Dorina DRAGANCHEVA 王登婷 Nanjing Hydraulic Research institute black Sea Coastal Association 9000 VarnaBulgaria Bulgarian Ship Hydrodynamics Centre Bulgarian Academy of Sciences9003 VarnaBulgaria

This paper discusses some previous, and presents some new experimental results on wave transmission over submerged breakwaters. The objective of this study is to evaluate wave transmission coefficient and develop a two-dimensional （2D） model as an improvement to the existing wave transmission coefficient models. Factors which affect wave transmission over stbmerged breakwaters are discussed through a series of laboratory experiments. Basic recommendations for evaluation and design of submerged rubble-monud breakwaters are presented. From the test results, a calculation formula of wave transmission coefficient is proposed.

关键词： submerged rubble breakwater wave transmission coefficient wave dissipation laboratory experiment

Herbivore and native plant diversity synergistically resist alien plant invasion regardless of nutrient conditions

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Plant Diversity 2024年第5期46卷 640-647页

作者： Liping Shan Meng Hou Key Laboratory of Wetland Ecology and Environment State Key Laboratory of Black Soils Conservation and UtilizationNortheast Institute of Geography and AgroecologyChinese Academy of SciencesChangchun 130102China

Alien plant invasion success can be inhibited by two key biotic factors:native herbivores and plant ***,few studies have experimentally tested whether these factors interact to synergistically resist invasion success,especially factoring in changing global environments(*** enrichment).Here we tested how the synergy between native herbivores and plant diversity affects alien plant invasion success in various nutrient *** this purpose,we exposed alien plant species in potmesocosms to different levels of native plant diversity(4 vs.8 species),native generalist herbivores,and high and low soil nutrient *** found that generalist herbivores preferred alien plants to native plants,inhibiting invasion success in a native *** inhibition was amplified by highly diverse native ***,the amplified effect between herbivory and native plant diversity was independent of nutrient *** results suggest that a higher diversity of native communities can strengthen the resistance of native generalist herbivores to alien plant invasions by enhancing herbivory *** synergistic effect remains in force in nutrient-enriched habitats that are always invaded by alien plant *** results shed light on the effective control of plant invasions using multi-trophic means,even in the face of future global changes.

关键词： Biological invasion Biotic resistance Diversity conservation Plant-herbivore interactions Resource availability Global change

Sky location of massive black hole binaries in the foreground of Galactic white dwarf binaries

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 97-108页

作者： Pan Guo Hong-Bo Jin Cong-Feng Qiao Yue-Liang Wu The International Centre for Theoretical Physics Asia-Pacific University of Chinese Academy of Sciences The School of Physical Sciences University of Chinese Academy of Sciences institute for Frontiers in Astronomy and Astrophysics Beijing Normal University National Astronomical Observatories Chinese Academy of Sciences institute of Theoretical Physics Chinese Academy of Sciences

For space-based gravitational wave （GW） detection,the main noise source for massive black hole binaries （MBHBs） is attributed to approximately 10～7double white dwarf binaries in the *** a GW source,the amplitude of the detector response,recorded by a space-based gravitational wave detector,exhibits a modulation effect with a year period when observing the source from various orbital *** the adverse conditions mentioned above,where there is a strong foreground noise and annual modulation in the signals,we employed the wavelet transform and the strong-amplitude relevant orbital position search methods,which allows the weak MBHB sources to achieve higher locating *** detail,for two MBHB sources of lower intensity,the precision of luminosity distance,represented by the ratio ?DL/DLat the 95%confidence level,is enhanced by factors of ～*** angular resolutions,denoted by??s,are enhanced by a factor of ～*** improvements increase the number of detectable GW sources,facilitate multi-messenger follow-up observations and provide constraints on the cosmological constant.

关键词： space-based gravitational wave detection gravitational waves massive black hole binaries

Attitudes towards suicide attempts broadcast on social media: an exploratory study of Chinese microblogs

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Attitudes towards suicide attempts broadcast on social media...

Coupling changes of soil functional gene abundances and extracellular enzyme activities across the diagnostic horizons of agricultural Isohumosols

第二十届全国心理学学术会议--心理学与国民心理健康

作者： Ang Li Xiaoxiao Huang Bibo Hao Bridianne O‘Dea Helen Christensen Tingshao Zhu Department of Psychology Beijing Forestry University black dog institute University of New South Wales institute of Psychology Chinese Academy of Sciences School of Computer and Control University of Chinese Academy of Sciences

Introduction. Broadcasting a suicide attempt on social media has become a public health concern in many countries, particularly in China. In these cases, social media users are likely to be the firstto witness the suicide attempt, and their attitudes may determine their likelihood of joining rescue efforts. This paper examines Chinese social media(Weibo) users’ attitudes towards suicide attempts broadcast on ***. A total of 4,969 Weibo posts were selected from a customised Weibo User Pool which consisted of 1.06 million active users. The selected posts were then independently coded by two researchers using a coding framework that assessed:(a) Themes,(b) General attitudes,(c) Stigmatising attitudes,(d) Perceived motivations, and(e) Desired *** and Discussion. More than one third of Weibo posts were coded as "stigmatising"(35%). Among these, 22%, 16%, and 15% of posts were coded as "deceitful", "pathetic", and "stupid", respectively. Among the posts which reflected different types of perceived motivations, 57% of posts were coded as "seeking attention". Among the posts which reflected desired responses, 37% were "not saving" and 28% were "encouraging suicide". Furthermore, among the posts with negative desired responses(i.e. "not saving" and "encouraging suicide"), 57% and 17% of them were related to different types of stigmatising attitudes and perceived motivations respectively. Specifically, 29% and 26% of posts reflecting both stigmatising attitudes and negative desired responses were coded as "deceitful" and "pathetic" respectively;while, 66% of posts reflecting both perceived motivations and negative desired responses were coded as "seeking attention". Very few posts "promoted literacy"(2%) or "provided resources"(8%). Gender differences existed in multiple ***. This paper confirms the need for stigma reduction campaigns for Chinese social media users to improve their attitudes towards those who broadcast their suicide

关键词： Suicide Social media Stigma Weibo Microblog China

来源： cnki会议评论

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Pedosphere 2024年第3期34卷 540-552页

作者： Zhuxiu LIU Haidong GU Xiaojing HU Zhenhua YU Yansheng LI Junjie LIU Jian JIN Xiaobing LIU Guanghua WANG State Key Laboratory of black Soils Conservation and Utilization Northeast Institute of Geography and AgroecologyChinese Academy of SciencesHarbin 150081(China) University of Chinese Academy of Sciences Beijing 100049(China)

Soil functional microbial taxa and extracellular enzymes are involved in a variety of biogeochemical cycling *** many studies have revealed the vertical change patterns of microbial communities along soil profile,the general understanding of the coupling changes in the functional gene abundances(FGAs)and extracellular enzyme activities(EEAs)in soil profiles is still limited,which hinders us from revealing soil ecosystem ***,we comparatively investigated the FGAs and EEAs in the diagnostic A,B,and C horizons of soil profiles obtained from two suborders of Isohumosols(Mollisols),Ustic and Udic Isohumosols,in Northeast China based on quantitative real-time polymerase chain reaction and standard fluorometric techniques,*** distribution patterns of both FGAs and EEAs significantly distinguished by the two soil suborders and were also separated from A to C ***,the variations of EEAs and FGAs were greater in Udic Isohumosols compared to Ustic Isohumosols along soil profiles,and greater changes were observed in C horizon than in A *** FGAs and EEAs correspondently decreased along the soil ***,when normalized by soil organic carbon,the specific EEAs significantly increased in deep soil horizons,suggesting that microorganisms will input more resources to the production of enzymes to ensure microbial nutrient requirements under resource *** importantly,we revealed that soil microbial nutrient demands were limited by carbon(C)and phosphorus(P),and the C and P limitations significantly increased along soil profiles with a greater C limitation observed in Ustic Isohumosols than in Udic ***,our findings provided solid evidence showing the links between FGAs,EEAs,and microbial nutrient limitations,which would be helpful for a better understanding of the ecosystem processes in soil profiles.

关键词： ecoenzymatic stoichiometry microbial nutrient limitation microbial nutrient requirement Mollisols soil ecosystem process soil profile