A novel 2-D cosmic ray position detector has been built and studied. It is integrated from a CsI（Na） crystal pixel array, an optical fiber array, an image intensifier and an ICCD camera. The 2-D positions of one cos...A novel 2-D cosmic ray position detector has been built and studied. It is integrated from a CsI（Na） crystal pixel array, an optical fiber array, an image intensifier and an ICCD camera. The 2-D positions of one cosmic ray track is determined by the location of a fired CsI（Na） pixel. The scintillation light of these 1.0× 1.0 mm CsI（Na） pixels is delivered to the image intensifier through fibers. The light information is recorded in the ICCD camera in the form of images, from which the 2-D positions can be reconstructed. The background noise and cosmic ray images have been studied. The study shows that the cosmic ray detection efficiency can reach up to 11.4%, while the false accept rate is less than 1%.展开更多
Species of wild rice(Oryza spp.)possess a wide range of stress tolerance traits that can be potentially utilized in breeding climate-resilient cultivated rice cultivars(Oryza sativa)thereby aiding global food security...Species of wild rice(Oryza spp.)possess a wide range of stress tolerance traits that can be potentially utilized in breeding climate-resilient cultivated rice cultivars(Oryza sativa)thereby aiding global food security.In this study,we conducted a greenhouse trial to evaluate the salinity tolerance of six wild rice species,one cultivated rice cultivar(IR64)and one landrace(Pokkali)using a range of electrophysiological,imaging,and whole-plant physiological techniques.Three wild species(O.latifolia,O.officinalis and O.coarctata)were found to possess superior salinity stress tolerance.The underlying mechanisms,however,were strikingly different.Na+accumulation in leaves of O.latifolia,O.officinalis and O.coarctata were significantly higher than the tolerant landrace,Pokkali.Na+accumulation in mesophyll cells was only observed in O.coarctata,suggesting that O.officinalis and O.latifolia avoid Na+accumulation in mesophyll by allocating Na+to other parts of the leaf.The finding also suggests that O.coarctata might be able to employ Na+as osmolyte without affecting its growth.Further study of Na+allocation in leaves will be helpful to understand the mechanisms of Na+accumulation in these species.In addition,O.coarctata showed Proto Kranz-like leaf anatomy(enlarged bundle sheath cells and lower numbers of mesophyll cells),and higher expression of C4-related genes(e.g.,NADPME,PPDK)and was a clear outlier with respect to salinity tolerance among the studied wild and cultivated Oryza species.The unique phylogenetic relationship of O.coarctata with C4 grasses suggests the potential of this species for breeding rice with high photosynthetic rate under salinity stress in the future.展开更多
文摘A novel 2-D cosmic ray position detector has been built and studied. It is integrated from a CsI（Na） crystal pixel array, an optical fiber array, an image intensifier and an ICCD camera. The 2-D positions of one cosmic ray track is determined by the location of a fired CsI（Na） pixel. The scintillation light of these 1.0× 1.0 mm CsI（Na） pixels is delivered to the image intensifier through fibers. The light information is recorded in the ICCD camera in the form of images, from which the 2-D positions can be reconstructed. The background noise and cosmic ray images have been studied. The study shows that the cosmic ray detection efficiency can reach up to 11.4%, while the false accept rate is less than 1%.
基金support from the Department of Industry,Science,Energy and Resources(project AISRF48490)China National Distinguished Expert Project(WQ20174400441)+5 种基金grant 31961143001 for Joint Research Projects between Pakistan Science Foundation and National Natural Science Foundation,and Chinese National Natural Science Foundation(Project 31870249)Zhong-Hua Chen was supported by Australian Research Council(DE140101143FT210100366)by Hort Innovation Australia Projects(VG17003,LP18000)Gayatri Venkataraman acknowledges support from the Department of Biotechnology,GOI(BT/Indo-Aus/09/03/2015)Sergey Shabala also acknowledges the support provided by the National Biodiversity Authority(NBA),India Government in assisting with O.coarctata material transfer(Appl.no.1712).
文摘Species of wild rice(Oryza spp.)possess a wide range of stress tolerance traits that can be potentially utilized in breeding climate-resilient cultivated rice cultivars(Oryza sativa)thereby aiding global food security.In this study,we conducted a greenhouse trial to evaluate the salinity tolerance of six wild rice species,one cultivated rice cultivar(IR64)and one landrace(Pokkali)using a range of electrophysiological,imaging,and whole-plant physiological techniques.Three wild species(O.latifolia,O.officinalis and O.coarctata)were found to possess superior salinity stress tolerance.The underlying mechanisms,however,were strikingly different.Na+accumulation in leaves of O.latifolia,O.officinalis and O.coarctata were significantly higher than the tolerant landrace,Pokkali.Na+accumulation in mesophyll cells was only observed in O.coarctata,suggesting that O.officinalis and O.latifolia avoid Na+accumulation in mesophyll by allocating Na+to other parts of the leaf.The finding also suggests that O.coarctata might be able to employ Na+as osmolyte without affecting its growth.Further study of Na+allocation in leaves will be helpful to understand the mechanisms of Na+accumulation in these species.In addition,O.coarctata showed Proto Kranz-like leaf anatomy(enlarged bundle sheath cells and lower numbers of mesophyll cells),and higher expression of C4-related genes(e.g.,NADPME,PPDK)and was a clear outlier with respect to salinity tolerance among the studied wild and cultivated Oryza species.The unique phylogenetic relationship of O.coarctata with C4 grasses suggests the potential of this species for breeding rice with high photosynthetic rate under salinity stress in the future.
