The precursor powders of Ca3Co4O9 were synthesized by a sol–gel method. The results of X‐ray diffraction and thermogravimetric and differential thermal analyses patterns indicate that pure Ca3Co4O9 powders could be obtained by calcining the precursor at 800°C for 2 h. High dense Ca3Co4O9 ceramic samples (∼99% of theoretical density) were prepared by the spark plasma sintering (SPS) method. Compared with the conventional sintering (CS), the SPS samples exhibit much higher electrical conductivity and power factor which are respectively about 118 S/cm and 3.51 × 10−4 W·(m·K2)−1. The SPS method is greatly effective for improving the thermoelectric properties of Ca3Co4O9 oxide ceramics.

Highly ͑00l͒ oriented Ca 3 Co 4 O 9 -based ceramics were fabricated by spark plasma sintering combined with a dynamic forging process. The grain orientation is effective in lowering the electrical resistivity and enhancing the thermoelectric power factor but with little influence on the Seebeck coefficient. A metallic-to-semiconducting transition temperature can be observed and the activation energy is almost independent of the La-doping. All of the Ca 3 Co 4 O 9 -based ceramic samples exhibit large thermoelectric power, and the figure of merit for La-doped Ca 3 Co 4 O 9 sample can reach 0.26 at 975 K, which can be a promising candidate of p-type material for high-temperature thermoelectric application. Co 2 O x , 4 have attracted much attention due to their promising thermoelectric ͑TE͒ properties and high-temperature stability, especially Ca 3 Co 4 O 9 -based compounds. Ca 3 Co 4 O 9 consists of alternating layers of a distorted CaO-CoO-CaO rocksalt-type layer and a CdI 2 -type CoO 2 layer stacked along the c-axis direction, and these two layers have similar lattice parameters. 5 The edge shared CoO 2 layers are considered to be responsible for the electrical conduction, whereas the rocksalt-type Ca 2 CoO 3 layers can be regarded as a charge reservoir to supply charge carriers into the CoO 2 layers.As for the TE materials, the conversion efficiency can be expressed by the figure of merit ZT = S 2 T / ͑where T, S, , and are the absolute temperature, TE power, electrical conductivity, and thermal conductivity, respectively͒. Therefore, a large TE power S, large electrical conductivity , and low thermal conductivity are highly desired for the development of a practical TE material. It is generally believed that texturation with high grain orientation in polycrystalline oxide ceramics can be used to improve the electrical, mechanical, and optical properties. 6 As previously reported, 7 the electrical transport properties of Ca 3 Co 4 O 9 are anisotropic due to its layered structure, and highly grain-aligned ceramics exhibited higher TE performance than randomly oriented Ca 3 Co 4 O 9 ceramics. Some previous results revealed that highly preferred orientation could be effective in decreasing the resistivity due to the shorter carrier path and the reduction in the scattering of the carriers at the grain boundaries or defects. For example, Tajima et al. 8 observed that c-axis oriented NaCo 2 O 4 ceramics exhibited good TE performance. Zhou et al. 9 used hot forging technique to obtain textured Ca 3 Co 4 O 9 and Bi 2.5 Ca 2.5 Co 2 O x ceramics and observed that their TE performance could be improved greatly.Therefore, the objective of this work is to find a suitable processing technology to prepare highly textured misfitlayered oxides ceramics and improve their TE properties. Generally, spark plasma sintering ͑SPS͒ has been demonstrated that it can sinter ceramic powders quickly to its full density at low temperature compared to conventional sintering methods. Dynamic hot forging process can be helpful to improve the ra...

We initiate the Westlake BioBank for Chinese (WBBC) pilot project with 4,535 whole-genome sequencing (WGS) individuals and 5,841 high-density genotyping individuals, and identify 81.5 million SNPs and INDELs, of which 38.5% are absent in dbSNP Build 151. We provide a population-specific reference panel and an online imputation server (https://wbbc.westlake.edu.cn/) which could yield substantial improvement of imputation performance in Chinese population, especially for low-frequency and rare variants. By analyzing the singleton density of the WGS data, we find selection signatures in SNX29, DNAH1 and WDR1 genes, and the derived alleles of the alcohol metabolism genes (ADH1A and ADH1B) emerge around 7,000 years ago and tend to be more common from 4,000 years ago in East Asia. Genetic evidence supports the corresponding geographical boundaries of the Qinling-Huaihe Line and Nanling Mountains, which separate the Han Chinese into subgroups, and we reveal that North Han was more homogeneous than South Han.

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Rad9 is conserved from yeast to humans and plays roles in DNA repair (homologous recombination repair, and base-pair excision repair) and cell cycle checkpoint controls. It has not previously been reported whether Rad9 is involved in DNA mismatch repair (MMR). In this study, we have demonstrated that both human and mouse Rad9 interacts physically with the MMR protein MLH1. Disruption of the interaction by a single-point mutation in Rad9 leads to significantly reduced MMR activity. This disruption does not affect S/M checkpoint control and the first round of G2/M checkpoint control, nor does it alter cell sensitivity to UV light, gamma rays or hydroxyurea. Our data indicate that Rad9 is an important factor in MMR and carries out its MMR function specifically through interaction with MLH1.

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Lithium niobate (LN) devices have been widely used in optical communication and nonlinear optics due to its attractive optical properties. The emergence of thin-film lithium niobate on insulator (LNOI) improves performances of LN-based devices greatly. However, a high-efficient fiber-chip optical coupler is still necessary for the LNOI-based devices for practical applications. In this paper, we demonstrate a highly efficient and polarizationindependent edge coupler based on LNOI. The coupler, fabricated by standard semiconductor process, shows a low fiber-chip coupling loss of 0.54 dB/0.59 dB per facet at 1550 nm for TE/TM light respectively, when coupled with ultra-high numerical aperture fiber (UHNAF) of which mode field diameter is about 3.2 μm. The coupling loss is lower than 1dB/facet for both TE and TM light at wavelengths longer than 1527nm. A relatively large tolerance for optical misalignment is also proved. The coupler shows a promising stability in high optical power and temperature variation.