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Among crop fruit trees, the apricot (Prunus armeniaca) provides an excellent model to study divergence and adaptation processes. Here, we obtain nearly 600 Armeniaca apricot genomes and four high-quality assemblies anchored on genetic maps. Chinese and European apricots form two differentiated gene pools with high genetic diversity, resulting from independent domestication events from distinct wild Central Asian populations, and with subsequent gene flow. A relatively low proportion of the genome is affected by selection. Different genomic regions show footprints of selection in European and Chinese cultivated apricots, despite convergent phenotypic traits, with predicted functions in both groups involved in the perennial life cycle, fruit quality and disease resistance. Selection footprints appear more abundant in European apricots, with a hotspot on chromosome 4, while admixture is more pervasive in Chinese cultivated apricots. Our study provides clues to the biology of selected traits and targets for fruit tree research and breeding.

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Malus baccata is one of four wild apple species that can hybridize with the cultivated apple species ( Malus domestica ). It is widely used in high-latitude apple-producing areas as a rootstock and breeding resource because of its disease resistance, and cold tolerance. A lack of a reference genome has limited the application of M. baccata for apple breeding. We present a draft reference genome for M. baccata . The assembled sequence consisting of 665 Mb, with a scaffold N50 value of 452 kb, included transposable elements (413 Mb) and 46,114 high-quality protein-coding genes. According to a genetic map derived from 390 sibling lines, 72% of the assembly and 85% of the putative genes were anchored to 17 linkage groups. Many of the M. baccata genes under positive selection pressure were associated with plant–pathogen interaction pathways. We identified 2,345 Transcription factor-encoding genes in 58 families in the M. baccata genome. Genes related to disease defense and cold tolerance were also identified. A total of 462 putative nucleotide-binding site (NBS)-leucine-rich-repeat (LRR) genes, 177 Receptor-like kinase (RLK) and 51 receptor-like proteins (RLP) genes were identified in this genome assembly. The M. baccata genome contained 3978 cold-regulated genes, and 50% of these gene promoter containing DREB motif which can be induced by CBF gene. We herein present the first M. baccata genome assembly, which may be useful for exploring genetic variations in diverse apple germplasm, and for facilitating marker-assisted breeding of new apple cultivars exhibiting resistance to disease and cold stress.

We examine whether the sign and magnitude of intra-daily returns have impact on expected volatility the next day or over longer future horizons. We first let the 'data speak', namely with minimal interference we capture the mapping between intra-daily returns and future volatility. We revisit the concept of news impact curves introduced by Engle and Ng (1993). Overall, we find that moderately good (intra-daily) news reduces volatility (the next day), while both very good news (unusual high intra-daily positive returns) and bad news (negative returns) increase volatility, with the latter having a more severe impact. The asymmetries disappear over longer horizons. We also introduce a new class of parametric models which feature asymmetries and with close ties to ARCH-type models, albeit applicable to a mixture of high and low frequency data. Models featuring asymmetries dominate, especially during the 2007-2008 financial crisis. * We like to thank Oliver Linton for comments and sharing with us software. In addition, we like to thank the Referees and the Editor for many helpful suggestions and comments on a previous version of the paper. We also like to thank

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Using lithium metal as anode in lithium batteries has attracted great attention due to its ultrahigh theoretical capacity of 3860 mA h g–1. However, the uneven deposition of lithium will cause dendrites, resulting in a poor cycling performance. Herein, a dendrite-free Li composite anode is developed by anchoring Ag nanoparticles in a wood-derived carbon (WDC) frame. The composite anode is integrally formed and has enough room for Li deposition due to the aligned open channels preserved from natural wood, which can decrease anode volume change greatly during cycling. The Ag nanoparticles, serving as seeds of lithium deposition, can help in the even deposition of lithium in the channels of carbon matrix due to their lithiophilicity and then avoid lithium dendrite formation. The composite anode exhibits excellent cyclic performance over 450 h at 1 mA cm–2 and over 300 h at 3 mA cm–2. The full cell of Ag-WDC@LFP also exhibits the smallest electrochemical polarization from 0.2 to 5 C, and a stable specific capacity and a high Coulombic efficiency at 1 C after a long time cycle. These results indicate that Ag nanoparticles play an important role in restraining dendrite formation during lithium plating/stripping. The wood-derived composite cathode can achieve no lithium dendrite formation and can be applied in other storage batteries.