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赑屃:力拔山兮驮功德

艺术品鉴 2024年第1期 50-53页

作者： s-Rong 不详

六子霸下,又名赑屃(bì xì),似龟有齿,喜欢负重,是碑下龟。墓碑文化在中国历史悠久,源远流长。现今遗留下来的很多古代墓碑都是“螭首龟趺”的形制,碑额雕刻蛟龙,碑底压着一只“龟趺”,比如有名的《徐达墓》《德明墓碑》《樊敏碑》等... 详细信息

六子霸下,又名赑屃(bì xì),似龟有齿,喜欢负重,是碑下龟。墓碑文化在中国历史悠久,源远流长。现今遗留下来的很多古代墓碑都是“螭首龟趺”的形制,碑额雕刻蛟龙,碑底压着一只“龟趺”,比如有名的《徐达墓》《德明墓碑》《樊敏碑》等。故而民谚有“王八驮石碑”一语。

关键词：樊敏碑赑屃螭首墓碑石碑龟

Diaspore characteristics and ecological adaptation of Bromus tectorum *** different distribution regions

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Journal of Arid Land 2013年第3期5卷 310-323页

作者： YaoBin LIU YuanMing ZHANG Robert s NOWAK Liliya DIMEYEVA Key Laboratory of Biogeography and Bioresource in Arid Land Xinjiang Institute of Ecology and GeographyChinese Academy of Sciences Graduate University of Chinese Academy of sciences Department of Natural Resources and Environmental science University of Nevada-RenoRenoNevada 89557USA Institute of Botany and Phytointroduction Almaty 050040Kazakhstan

The invasion of nonnative plants is considered one of the main threats to the structure and function of North American ecosystems. Moreover, they can alter ecosystem processes and reduce biodiversity. In arid and semi-arid region of North America, the species of European annual grass Bromus tectorum L. is an outstanding example of these problems, which not only increase the fire density and change the fire regime, but replace native communities. Therefore, there are amount of researches on B. tectorum, including resource acquisition, water use efficiency and growth. Whereas the relevant research on the morphology of diaspore is scare. Diaspores have a fundamental role in seed germination and seedling establishment. Besides, as an important link between different generations, diaspores have a vital significance on individual reproduction and population extension. Hence, dias- pores under selection for studying have an important implication. This study compares differences in seed mor- phology for Bromus tectorum collected from the United states, Kazakhstan, and Xinjiang of China. The following indices of B. tectorum diaspores were analyzed： size, thickness of covering layers, and micromorphological char- acteristics of the base, middle and transition area of diaspores as well as of the awn. Micromorphology of the lemma and the cross-section of the diaspore were observed by scanning electron microscopy. Results showed that thick- ness of the lemma and the palea of diaspores from B. tectorum-infested grasslands in the United states were re- duced （P〈0.05）, likely because of environmental influences. This reduction facilitated the germination of diaspores and lowered the resistance of B. tectorum to adverse environmental conditions. The length of the awn also in- creased significantly （P〈0.05）, which helped in dispersal and anchoring of diaspores. Therefore, B. tectorum adapted ecologically to its new environment in the United states by strengthening its establishment a

关键词： Bromus tectorum diaspore micromorphology lemma Kazakhstan United states Xinjiang of China

MULTIPLE sOLUTIONs FOR NONAUTONOMOUs sECOND ORDER PERIODIC sYsTEMs

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Acta Mathematica scientia 2010年第1期30卷 350-358页

作者： Zdzislaw Denkowski Leszek Gasiński Nikolaos s.Papageorgiou Institute of Computer science Jagiellonian University Department of Mathematics National Technical UniversityZografou CampusAthens 15780Greece

We study nonautonomonus second order periodic systems with a nonslnooth potential. Using the nonsmooth critical theory, we establish the existence of at least two nontrivial solutions. Our framework incorporates large... 详细信息

关键词： locally Lipschitz potential generalized subdifferentiM coercive functional critical point local linking theorem nonsmooth Palais-smale condition multiple nontrivial solutions

Xyloglucans of Monocotyledons Have Diverse structures

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Molecular Plant 2009年第5期2卷 943-965页

作者： Yves s.Y. Hsieh Philip J. Harris school of Biological sciences The University of Auckland Private Bag 92019 Auckland New Zealand

Except in the Poaceae, little is known about the structures of the xyloglucans in the primary walls of monocotyledons. Xyloglucan structures in a range of monocotyledon species were examined. Wall preparations were isolated, extracted with 6 M sodium hydroxide, and the extracts treated with a xyloglucan-specific endo-（1→4）-β-glucanase preparation. The oligosaccharides released were analyzed by high-performance anion-exchange chromatography and by matrix-assisted laser-desorption ionization time-of-flight mass spectrometry. Oligosaccharide profiles of the non-commelinid monocotyledons were similar to those of most eudicotyledons, indicating the xyloglucans were fucogalactoxyloglucans, with a XXXG a core motif and the fucosylated units XXFG and XLFG. An exception was Lemna minor （Araceae）, which yielded no fucosylated oligosaccharides and had both XXXG and XXGn core motifs. Except for the Arecales （palms） and the Dasypogonaceae, which had fucogalactoxyloglucans, the xyloglucans of the commelinid monocotyledons were structurally different. The Zingiberales and Commelinales had xyloglucans with both XXGn and XXXG core motifs; small proportions of XXFG units, but no XLFG units, were present. In the Poales, the Poaceae had xyloglucans with a XXGn core motif and no fucosylated units. In the other Poales families, some had both XXXG and XXGn core motifs, others had only XXXG; XXFG units were present, but XLFG units were not.

关键词： Commelinid monocotyledons non-commelinid monocotyledons plant cell walls Poaceae xyloglucans xyloglucan-specific endo-(1→4)-β-glucanase.

Cellular reprogramming in farm animals： an overview of iPsC generation in the mammalian farm animal species

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Journal of Animal science and Biotechnology 2016年第4期7卷 459-467页

作者： J. Ogorevc s. Orehek P. DovcC Department of Animal science Biotechnical Faculty University of LjubljanaDomzale Slovenia

Establishment of embryonic stem cell （EsC） lines has been successful in mouse and human, but not in farm animals. Development of direct reprogramming technology offers an alternative approach for generation of pluripotent stem cells, applicable also in farm animals. Induced pluripotent stem cells （iPsCs） represent practically limitless, ethically acceptable, individuum-specific source of pluripotent cells that can be generated from different types of somatic cells, iPsCs can differentiate to all cell types of an organism＇s body and have a tremendous potential for numerous applications in medicine, agriculture, and biotechnology. However, molecular mechanisms behind the reprogramming process remain largely unknown and hamper generation of bona fide iPsCs and their use in human clinical practice. Large animal models are essential to expand the knowledge obtained on rodents and facilitate development and validation of transplantation therapies in preclinical studies. Additionally, transgenic animals with special traits could be generated from genetically modified pluripotent cells, using advanced reproduction techniques. Despite their applicative potential, it seems that iPsCs in farm animals haven＇t received the deserved attention. The aim of this review was to provide a systematic overview on iPsC generation in the most important mammalian farm animal species （cattle, pig, horse, sheep, goat, and rabbit）, compare protein sequence similarity of pluripotency-related transcription factors in different species, and discuss potential uses of farm animal iPsCs. Literature mining revealed 32 studies, describing iPsC generation in pig （13 studies）, cattle （5） horse （5）, sheep （4）, goat （3）, and rabbit （2） that are summarized in a concise, tabular format.

关键词： Cellular reprogramming Farm animals Induced pluripotent stem cells Pluripotency

Natural Convection of Fe_3O_4-Ethylene Glycol Nanofluid under the Impact of Electric Field in a Porous Enclosure

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Communications in Theoretical Physics 2018年第6期69卷 667-675页

作者： M.sheikholeslami s.A.shehzad R.Kumar Department of Mechanical Engineering Babol Noshirvani University of Technology Department of Mathematics COMSATS Institute of Information Technology Department of Mathematics Central University of Himachal Pardesh

Free convection of FeaO4-Ethylene glycol nanofluid in existence of Coulomb forces is studied. Effect of thermal radiation is taken into account. Properties of nanofluid are varied with supplied voltage and shape of nanoparticles. The bottom wall is considered as positive electrode. Control Volume based Finite Element Method is used to obtain the results, which are the roles of Darcy number （Da）, radiation parameter （Rd）, Rayleigh number （Ra）, nanofluid volume fraction （qs）, and supplied voltage （△φ）. Results indicate that Nusselt number is an enhancing function of supplied voltage and Darcy number. Maximum values for temperature gradient are occurred for platelet shape nanoparticles.

关键词： electric field thermal radiation nanofluid shape of nanoparticles porous media

Consumption of rice and fish in an electronic waste recycling area contributes significantly to total daily intake of mercury

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Journal of Environmental sciences 2015年第12期27卷 83-86页

作者： Hanyong Peng Michael s.Reid X.Chris Le Division of Analytical and Environmental Toxicology Department of Laboratory Medicine and PathologyUniversity of Alberta

Mercury is a global pollutant due to its widespread use,emission,and long-range transport（Blum,2013;Pacyna et al.,2010）.It is considered a priority pollutant due to its neurological toxicity,persistence,and bioaccumulation（Pacyna et al.,2010;sharma et al.,2015）.Mercury pollution can occur when products that contain mercury are improperly disposed of and mercury is released into the air,water,and soil（Zhang and Wong,2007）.An estimated 22%of the annual world usage of mercury is in electrical equipment such as batteries,thermometers,and discharge lamps,and electronic devices such as monitors and

关键词： Mercury Methyl mercury Electronic waste Biomonitoring Dietary intake Human exposure assessment Environmental health

A sMALLEsT sINGULAR VALUE METHOD FOR sOLVING INVERsE EIGENVALUE PROBLEMs

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Journal of Computational Mathematics 1996年第1期14卷 23-31页

作者： s.F. Xu(Department of Mathematics, Peking University, Beijing) 北京大学数学系北京

Utilizing the properties of the smallest singular value of a matrix, we propose a new, efficient and reliable algorithm for solving nonsymmetric matrix inverse eigenvalue problems, and compare it with a known method. ... 详细信息

关键词： Math A sMALLEsT sINGULAR VALUE METHOD FOR sOLVING INVERsE EIGENVALUE PROBLEMs

Probiotics and gut health:A special focus on liver diseases

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World Journal of Gastroenterology 2010年第4期16卷 403-410页

作者： silvia Wilson Gratz Hannu Mykkanen Hani s El-Nezami Rowett Institute of Nutrition and Health University of Aberdeen Greenburn Road Aberdeen AB21 9SNUnited Kingdom school of Public Health and Clinical Nutrition University of KuopioPO Box 162770211 KuopioFinland Food and Health Research Centre University of KuopioPO Box 162770211 KuopioFinland school of Biological sciences University of Hong KongS5-13 Kadoorie Biological Sciences BuildingPokfulamHong KongChina

Probiotic bacteria have well-established beneficial ef-fects in the management of diarrhoeal *** evidence suggests that probiotics have the potential to reduce the risk of developing inflammatory bowel diseases and intestinal bacterial overgrowth after gut *** liver health,the main benefits of probiotics might occur through preventing the production and/or uptake of lipopolysaccharides in the gut,and therefore reducing levels of low-grade *** immune stimulation by probiotics through processes involving dendritic cells might also be beneficial to the host immunological status and help prevent pathogen *** fat metabolism also seems to be influenced by the presence of commensal bacteria,and potentially by probiotics;although the mechanisms by which probiotic might act on the liver are still ***,this might be of major importance in the fu-ture because low-grade inflammation,hepatic fat infil-tration,and hepatitis might become more prevalent as a result of high fat intake and the increased prevalence of obesity.

关键词： Probiotics Liver Gut Endotoxin Barrier function Ethanol Bacterial overgrowth Translocation