Electronic structure of cuprate-nickelate infinite-layer heterostructure

The discovery of superconductivity in Sr/Ca-doped infinite-layer nickelates Nd(La)NiO_(2)thin films inspired extensive experimental and theoretical research.However,research on the possibilities of enhanced critical temperature by interface heterostructure is still lacking.Due to the similarities of the crystal structure and band structure of infinite-layer nickelate La NiO_(2)and cuprate CaCuO_(2),we investigate the crystal,electronic and magnetic properties of La NiO_(2):CaCuO_(2)heterostructure using density functional theory and dynamical mean-field theory.Our theoretical results demonstrate that,even a very weak inter-layer z-direction bond is formed,an intrinsic charge transfer between Cu-3d_(x^(2)-y^(2))and Ni-3d_((x^(2)-y^(2)))orbitals is obtained.The weak interlayer hopping between Cu and Ni leaves a parallel band contributed by Ni/Cu-3d_((x^(2)-y^(2)))orbitals near the Fermi energy.Such an infinite-layer heterostructure with negligible interlayer interaction and robust charge transfer opens a new way for interface engineering and nickelate superconductors.

Allene oxide synthase 1 contributes to limiting grain arsenic accumulation and seedling detoxification in rice

Arsenic(As)is a cancerogenic metalloid ubiquitously distributed in the environment,which can be easily accumulated in food crops like rice.Jasmonic acid(JA)and its derivatives play critical roles in plant growth and stress response.However,the role of endogenous JA in As accumulation and detoxification is still poorly understood.In this study,we found that JA biosynthesis enzymes Allene Oxide Synthases,OsAOS1 and OsAOS2,regulate As accumulation and As tolerance in rice.Evolutionary bioinformatic analysis indicated that AOS1 and AOS2 have evolved from streptophyte algae(e.g.the basal lineage Klebsormidium flaccidum)-sister clade of land plants.Compared to other two AOSs,OsAOS1 and OsAOS2 were highly expressed in all examined rice tissues and their transcripts were highly induced by As in root and shoot.Loss-of-function of OsAOS1(osaos1-1)showed elevated As concentration in grains,which was likely attributed to the increased As translocation from root to shoot when the plants were subjected to arsenate[As(Ⅴ)]but not arsenite[As(Ⅲ)].However,the mutation of OsAOS2(osaos2-1)showed no such effect.Moreover,osaos1-1 and osaos2-1 increased the sensitivity of rice plants to both As(Ⅴ)and As(Ⅲ).Disrupted expression of genes involved in As accumulation and detoxification,such as OsPT4,OsNIP3;2,and OsOASTL-A1,was observed in both osaos1-1 and osaos2-1 mutant lines.In addition,a As(Ⅴ)-induced significant decrease in Reactive Oxygen Species(ROS)production was observed in the root of osaos1-1 but not in osaos2-1.Taken together,our results indicate OsAOS1 modulates both As allocation and detoxification,which could be partially attributed to the altered gene expression profiling and ROS homeostasis in rice while OsAOS2 is important for As tolerance.