Restoration of cropland(termed 'Farm') after abandonment including shrubs(termed 'Shrub'),trees(termed 'Tree') and natural grassland(termed 'Grass') has become a routine process aimed t...Restoration of cropland(termed 'Farm') after abandonment including shrubs(termed 'Shrub'),trees(termed 'Tree') and natural grassland(termed 'Grass') has become a routine process aimed to improve land productivity and control desertification. During this restoration process, soil macro-faunal diversity, and trophic structure were investigated at four types of sites(Farm, Shrub, Tree, and Grass)during growing season in the semi-arid agro-pasture zone of northern China. Results indicated that the Staphylinidae family was found to dominate at the Grass, Shrub, and Tree sites, whiles larval Pyralidae individuals were found at the Grass site only. The density of the omnivores(i.e., Formicidae family) was significantly(P<0.05) greater at the Grass site than at the Tree and Farm sites. The total density and richness of predator and phytophages were found to be markedly(P<0.05) greater at the Grass site than at the Farm site. Meanwhile, we found the taxon richness of predators was significantly(P<0.05) higher at the Shrub site than at the Farm and Tree sites. Compared with the Farm and afforested Shrub/Tree sites,the Grass site had greater density, taxon richness, and Shannon index(P<0.05). In conclusion, natural restoration of abandoned croplands toward grassland was an effective strategy relative to artificial afforestation for improvement of soil biological diversity. Moreover, planting shrub is a preferable measure in abandoned croplands for land development in the semi-arid agro-pasture zone of northern China.展开更多
G-Quadruplexes(GQs),which are formed by G-rich DNA sequences in human telomeres,have become an attractive target for cancer treatment.The ligands to stabilize the conformation of human telomeric GQs in vivo are partic...G-Quadruplexes(GQs),which are formed by G-rich DNA sequences in human telomeres,have become an attractive target for cancer treatment.The ligands to stabilize the conformation of human telomeric GQs in vivo are particularly important for structure-based ligand design and drug development targeting the noncanonical DNA structure.Here we report the conformational conversion of Tel26 induced by a naphthalene diimide(NDI)ligand in K^(+)buffer,even at cellular physiological temperature(37℃)and under mimetic cellular crowding conditions created by Ficoll 70.We provide an insight into the dynamic conversion from initial hybrid-2 GQ topology to final parallel GQ topology.These results are helpful for the design of ligands with GQ conformation regulation.展开更多
基金supported by the National Natural Science Foundation of China (41661054 41867005)+4 种基金Project for Top Young Talent Candidates of Ningxia (RQ0010)Science Research Foundation of Ningxia Higher Education (NGY2018007)Ningxia Natural Science Foundation (2018AAC02004)Specialized Foundation for Fundamental Condition Construction in Ningxia Science and Technology (2018DPC05021)the Project of First-Class University of Western China for Key Laboratory of Ningxia University (NXYLXK2017B06, GZXM2017001)
文摘Restoration of cropland(termed 'Farm') after abandonment including shrubs(termed 'Shrub'),trees(termed 'Tree') and natural grassland(termed 'Grass') has become a routine process aimed to improve land productivity and control desertification. During this restoration process, soil macro-faunal diversity, and trophic structure were investigated at four types of sites(Farm, Shrub, Tree, and Grass)during growing season in the semi-arid agro-pasture zone of northern China. Results indicated that the Staphylinidae family was found to dominate at the Grass, Shrub, and Tree sites, whiles larval Pyralidae individuals were found at the Grass site only. The density of the omnivores(i.e., Formicidae family) was significantly(P<0.05) greater at the Grass site than at the Tree and Farm sites. The total density and richness of predator and phytophages were found to be markedly(P<0.05) greater at the Grass site than at the Farm site. Meanwhile, we found the taxon richness of predators was significantly(P<0.05) higher at the Shrub site than at the Farm and Tree sites. Compared with the Farm and afforested Shrub/Tree sites,the Grass site had greater density, taxon richness, and Shannon index(P<0.05). In conclusion, natural restoration of abandoned croplands toward grassland was an effective strategy relative to artificial afforestation for improvement of soil biological diversity. Moreover, planting shrub is a preferable measure in abandoned croplands for land development in the semi-arid agro-pasture zone of northern China.
文摘G-Quadruplexes(GQs),which are formed by G-rich DNA sequences in human telomeres,have become an attractive target for cancer treatment.The ligands to stabilize the conformation of human telomeric GQs in vivo are particularly important for structure-based ligand design and drug development targeting the noncanonical DNA structure.Here we report the conformational conversion of Tel26 induced by a naphthalene diimide(NDI)ligand in K^(+)buffer,even at cellular physiological temperature(37℃)and under mimetic cellular crowding conditions created by Ficoll 70.We provide an insight into the dynamic conversion from initial hybrid-2 GQ topology to final parallel GQ topology.These results are helpful for the design of ligands with GQ conformation regulation.
