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Summary Yield in rice is determined mainly by panicle architecture. Using map‐based cloning, we identified an R2R3 MYB transcription factor REGULATOR OF GRAIN NUMBER1 (RGN1) affecting grain number and panicle architecture. Mutation of RGN1 caused an absence of lateral grains on secondary branches. We demonstrated that RGN1 controls lateral grain formation by regulation of LONELY GUY (LOG) expression, thus controlling grain number and shaping panicle architecture. A novel favourable allele, RGN1 C, derived from the Or‐I group in wild rice affected panicle architecture by means longer panicles. Identification of RGN1 provides a theoretical basis for understanding the molecular mechanism of lateral grain formation in rice; RGN1 will be an important gene resource for molecular breeding for higher yield.

TEOSINTE BRANCHED1/CYCLOIDEA/PCF (TCP) proteins are plant-specific transcription factors that play significant roles in plant growth, development, and stress response. Rye is a high-value crop with strong resistance to adverse environments. However, the functions of TCP proteins in rye are rarely reported. Based on a genome-wide analysis, the present study identified 26 TCP genes (ScTCPs) in rye. Mapping showed an uneven distribution of the ScTCP genes on the seven rye chromosomes and detected three pairs of tandem duplication genes. Phylogenetic analysis divided these genes into PCF (Proliferrating Cell Factors), CIN (CINCINNATA), and CYC (CYCLOIDEA)/TB1 (Teosinte Branched1) classes, which showed the highest homology between rye and wheat genes. Analysis of miRNA targeting sites indicated that five ScTCP genes were identified as potential targets of miRNA319. Promoter cis-acting elements analysis indicated that ScTCPs were regulated by light signals. Further analysis of the gene expression patterns and functional annotations suggested the role of a few ScTCPs in grain development and stress response. In addition, two TB1 homologous genes (ScTCP9 and ScTCP10) were identified in the ScTCP family. Synteny analysis showed that TB1 orthologous gene pairs existed before the ancestral divergence. Finally, the yeast two-hybrid assay and luciferase complementation imaging assay proved that ScTCP9, localized in the nucleus, interacts with ScFT (Flowering locus T), indicating their role in regulating flowering time. Taken together, this comprehensive study of ScTCPs provides important information for further research on gene function and crop improvement.

Transition metal- and N-codoped carbon nanotubes (CNTs) have superior catalytic activity because the curling surface enhances the bonding ability of atoms within CNTs to other species. However, it is a great challenge to prepare CNTs with transition metal- and N-doped at high level during the growth of CNTs. Here, (Fe,N-codoped CNT)/(Fe-based nanoparticle) (Fe,N-CNT/FeNP) hybrid nanostructures are for the first time prepared through the carbonization of Fe-doped g-C3N4. The doping of Fe and N is simultaneously realized during the formation of CNTs. Meanwhile, the abundant and homogeneous Fe and N in Fe-doped g-C3N4 ensure high-level and uniform doping of Fe and N in CNTs. The Fe,N-CNT/FeNP hybrid nanostructures have several types of active components, including homogeneously distributed coordinating Fe moieties (FeCxNy or FeNx) and CFe15.1 nanoparticles embedded in Fe,N-CNTs, towards oxygen reduction reaction (ORR). A superior ORR electrocatalytic performance is therefore obtained on the Fe,N-CNT/FeNP nanohybrids. Our preparation method opens an avenue to preparation of CNTs with transition metal- and N-doping at high-level, and the superior performance of Fe,N-CNT/FeNP nanostructures for ORR will be very helpful to the development of fuel cells and metal-air batteries.

Electromagnetic absorption and electromagnetic interference (EMI) shielding materials, especially absorption-based EMI shielding materials, are urgently desired to eliminate increasingly serious electromagnetic radiation pollution. Metal carbides exhibit great promise in realizing excellent EMI shielding owing to their outstanding electrical conductivity. However, because of the same reason, the electromagnetic wave reflection from the metal carbide films is hardly diminished and thereby metal carbides cannot realize absorption-based EMI shielding. Herein, metal carbide/Ni hybrid nanostructures are designed to realize electromagnetic absorption and absorption-based EMI shielding. The hybrid nanostructures are prepared by in situ reduction of Ni on metal carbide nanosheets. The loading of Ni greatly increases the impedance matching and attenuation constants. Metal carbide/Ni hybrids achieve a reflection loss of −41.7 dB at 10.8 GHz with a thickness of 1.8 mm. An EMI shielding effectiveness larger than 60 dB is achieved in the whole X-band with a metal carbide/Ni hybrid film of 50 μm. Particularly, the absorption contributes 98.9% of total EMI shielding effectiveness, indicating the absorption-based EMI shielding. In addition, the metal carbide/Ni hybrid film exhibits very good mechanical properties and long-term stability in water. Our findings are very important for the development of electromagnetic absorption and absorption-based EMI shielding materials.

The prevalence of abnormal glucose and lipid metabolism and its relevant diseases has increased year by year, and it has become a problem that threatens human health. Therefore, finding a more effective way to prevent and treat diseases related to abnormal glucose and lipid metabolism has become an urgent public problem. Agmatine is a polyamine substance which widely presents in mammals.It is a metabolite produced by decarboxylation of糖脂代谢异常及其所诱发的各种疾病的患病率逐年上升，已成为当今威胁人类健康的常见问题。寻找更为有效的预防和治疗与糖脂代谢异常相关疾病的方法已成为一个亟待解决的问题。胍丁胺(agmatine)是一种广泛存在于哺乳动物体内的多胺类物质，是

Suzuki coupling is of paramount importance in C-C coupling reactions. However, Suzuki coupling reactions are generally catalyzed by homogeneous catalysts under thermal heating, which results in difficulties in the catalyst separation and consumes a relatively large amount of energy. g-C3 N4 /Pd has been successfully prepared for photocatalytic Suzuki coupling reactions. The g-C3 N4 /Pd is prepared through the reduction of a Pd source in the presence of g-C3 N4 . The Pd is found to exist as Pd nanoparticles and Pd(II) species on g-C3 N4 . Owing to the good light absorption of g-C3 N4 and the excellent catalytic activity of the Pd species, the g-C3 N4 /Pd shows an excellent photocatalytic performance in Suzuki coupling reactions with a TOF of 47.3 h-1 , which is almost twice that of a commercial homogeneous catalyst Pd(PPh3 )4 , under thermal heating. Moreover, g-C3 N4 /Pd displays very good recyclability and wide applicability for Suzuki coupling reactions. Our findings provide a green and sustainable method for the catalysis of Suzuki coupling reactions.

Summary Rice (Oryza sativa L.) cultivars harbour morphological and physiological traits different from those of wild rice (O. rufipogon Griff.), but the molecular mechanisms underlying domestication remain controversial. Here, we show that awn and long grain traits in the near‐isogenic NIL‐GLA are separately controlled by variations within the GLA (Grain Length and Awn Development) gene, a new allele of GAD1/RAE2, which encodes one member of the EFPL (epidermal patterning factor‐like protein) family. Haplotype analyses and transgenic studies revealed that InDel1 (variation for grain length, VGL) in the promoter region of GLA (GLAVGL) increases grain length by promoting transcription of GLA. Absence of InDel3 (variation for awn formation, VA) in the coding region (CDS) of GLA (GLA va) results in short awn or no awn phenotypes. Analyses of minimum spanning trees and introgression regions demonstrated that An‐1, an important gene for awn formation, was preferentially domesticated and its mutation to an‐1 was followed by GLA and An‐2. Gene flow then occurred between the evolved japonica and indica populations. Quality analysis showed that GLA causes poor grain quality. During genetic improvement, awnlessness was selected in ssp. indica, whereas short–grained and awnless phenotypes with good quality were selected in japonica. Our findings facilitate an understanding of rice domestication and provide a favourable allele for rice breeding.

Transition metal- and N-codoped carbon nanotubes (CNTs) have superior catalytic activity because the curling surface enhances the bonding ability of atoms within CNTs to other species. However, it is a great challenge to prepare CNTs with transition metal- and N-doped at high level during the growth of CNTs. Here, (Fe,N-codoped CNT)/(Fe-based nanoparticle) (Fe,N-CNT/FeNP) hybrid nanostructures are for the first time prepared through the carbonization of Fe-doped g-C

Suzuki coupling is of paramount importance in C-C coupling reactions. However, Suzuki coupling reactions are generally catalyzed by homogeneous catalysts under thermal heating, which results in difficulties in the catalyst separation and consumes a relatively large amount of energy. g-C

The control of the emission from electric and magnetic dipoles is highly desired for the development of optic chips. Although the emission of electric dipole has been successfully controlled by plasmonic nanoantenna, the control of magnetic dipole emission is relatively difficult. Here, we systematically study the effect of electric and magnetic modes of Au nanocups on the emission of electric and magnetic dipoles. The emission of electric dipole can be enhanced by both the electric and magnetic mode of the Au nanocup, while the emission of the magnetic dipole is only increased by the magnetic mode. The enhancement exhibits wavelength dependence. The wavelength of the largest enhancement is determined by the resonance wavelength of electric and magnetic modes. The enhancement values for electric and magnetic dipoles are determined by the near-field electric and magnetic field enhancements, respectively. More importantly, the emission pattern of magnetic dipole is greatly modified by the magnetic mode of Au nanocup. The directional emission of magnetic dipole is first time realized by use of the magnetic mode of the Au nanocup. Our findings deepen the understanding of the plasmon-controlled emission of electric and magnetic dipoles and will be very helpful to the development of the nanophotonic chips.

The lower seed setting is one of the major hindrances which face grain yield in rice. One of the main reasons to cause low spikelet fertility (seed setting) is male sterility or pollen abortion. Notably, pollen abortion has been frequently observed in advanced progenies of rice. In the present study, 149 BC 2 F 6 individuals with significant segregation in spikelet fertility were generated from the cross between N040212 ( indica ) and Nipponbare ( japonica ) and used for primary gene mapping. Three QTLs, qSS-1, qSS-7 and qSS-9 at chromosomes 1, 7 and 9, respectively, were found to be associated with seed setting. The recombinant analysis and the physical mapping information from publicly available resources exhibited that the qSS-, qSS-7 and qSS-9 loci were mapped to an interval of 188, 701 and 3 741 kb, respectively. The seed setting responsible for QTL qSS-1 was further fine mapped to 93.5 kb by using BC 2 F 7 population of 1 849 individuals. There are 16 possible putative genes in this 93.5 kb region. Pollen vitality tests and artificial pollination indicated that the male gamete has abnormal pollen while the female gamete was normal. These data showed that low seed setting rate relative to qSS-1 may be caused by abnormal pollen grains. These results will be useful for cloning, functional analysis of the target gene governing spikelet fertility (seed setting) and understanding the genetic bases of pollen sterility.

As a green pollution-free reaction, oxygen reduction reaction (ORR) plays a significant role in many energy storage and conversion devices. Although commercial Pt/C possesses the highest ORR activity (especially in acidic medium), the high cost, low stability and poor methanol tolerance making the development of non-platinum electrocatalysts with high performance especially important. Herein, we design and synthesize a carbon nanofiber decorated by Ti4O7/Ti3O5 dual-phase nanoparticles (CNF/T4/T3) as ORR catalysts with excellent activity. With the employment of electrospinning followed by precisely controlled calcination process, the composite catalysts with uniform fibrous morphology can be obtained. Such CNF/T4/T3 composite catalysts exhibited an improved electrochemical performance with onset and half-wave potential of 0.91 V and 0.78 V respectively in alkaline solution. By comparing the catalytic performance with the pure T4 or T3 phase decorated on the same carbon nanofiber, it is found that the mixture of the two titanium sub-oxide phases can optimize the onset potential and limited current density at the same time. Density functional theory calculations suggest that different steps of ORR take place on T3 and T4 successively, which is the main reason of the excellent ORR performance for the dual-phase structure. This work provided a novel designing concept for the functional electrocatalysts using electrospinning technique for the application of energy storage and conversion.

Brassinosteroids (BRs) are a class of plant-specific steroidal hormones that play important roles in multiple biological processes. In this paper, a classic rice mutant gsor300084, showing erect leaves and semi-dwarf stature, was characterized. Morphological analysis in darkness showed that the mesocotyl of the gsor300084 mutant did not elongate when grown in darkness. Coleoptile elongation and root growth were less affected by the exogenous application of brassinolide (BL), the most active form of BR, in gsor300084 than in the wild-type rice variety Matsumae. Lamina joint bending analysis also showed that gsor300084 was less sensitive to exogenous BL than Matsumae. These results suggested that the gsor300084 mutant is defective in BR sensitivity. Map-based cloning indicated that gsor300084 is a novel allelic mutant of the DWARF61 (D61) gene, which encodes the putative BR receptor OsBRI1. A single-base mutation appears in the LRR domain of OsBRI1, changing the 444th amino acid from tryptophan (W) to arginine (R). Subcellular localization analysis suggested that both the wild-type and mutant OsBRI1 protein are localized at the cytoplasmic membrane. Structure modeling revealed that the W444R substitution may affect the perception of BRs by the LRR domain.

Awns, important domestication and agronomic traits in rice (Oryza sativa L.), are conferred by polygenes and the environment. Near isogenic line (NIL) pairs BM33 and BM38 were constructed from crosses between awnless japonica cv Nipponbare as recurrent parent, and lines SLG or Funingxiaohongmang (awned japonica accessions), respectively, as donors. In order to study the genetic and molecular mechanism of awning, two unknown, independent genes with additive effects were identified in a cross between the NILs. To map and clone the two genes, a BC4F4 population of 8,103 individuals and a BC4F6 population of 11,206 individuals were constructed. Awn3-1 was fine mapped to a 101.13 kb genomic region between Indel marker In316 and SNP marker S9-1 on chromosome 3. Nine predicted genes in the interval were annotated in the Rice Annotation Project Database (RAP-DB), and Os03g0418600 was identified as the most likely candidate for Awn3-1 through sequence comparisons and RT-PCR assays. Awn4-2 was fine mapped to a 62.4 kb genomic region flanked by simple sequence repeat (SSR) marker M1126 and Indel maker In73 on chromosome 4L. This region contained the previously reported gene An-1 that regulates awn development. Thus, An-1 may be the candidate gene of Awn4-2. These results will facilitate cloning of the awn genes and thereby provide an understanding of the molecular basis of awn development.