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The response mechanism of the southeastern Tibet Plateau to the Indian-Eurasian collision is still controversial. The widely distributed shear systems in the Sanjiang area especially Ailaoshan-Red River shear system contribute a window to understand the tectonic evolution. Here we compile comprehensive geochronological data of the high-grade metamorphic rocks from the Ailaoshan-Red River shear system. The data reveal that the Ailaoshan metamorphic belt should be metamorphic complex with Middle-Late Triassic magmatic rocks and Cenozoic granites besides the Precambrian basement. The Cenozoic U-Pb age results of granitic rocks by accessory mineral within the Ailaoshan-Red River shear system range from ~41 Ma to ~20 Ma. The results of Ar-Ar dating of various minerals are in the range of ~40–5 Ma, concentrated in ~35–20 Ma. The U-Pb age results coincide basically with Ar-Ar data, indicating a rapid cooling process and reflecting a possible tectonic transition at ~20 Ma. The metamorphism and magmatism since the Cenozoic were not only unique to the Ailaoshan metamorphic belt, but also existed in the Chongshan and Gaoligongshan metamorphic belts. We infer that the Sanjiang area has a similar lateral extrusion deformation background and corresponds to the response of the India-Eurasia convergence process.

Mutations in the well-known Myostatin (MSTN) produce a ‘double-muscle’ phenotype, which makes it commercially invaluable for improving livestock meat production and providing high-quality protein for humans. However, mutations at different loci of the MSTN often produce a variety of different phenotypes. In the current study, we increased the delivery ratio of Cas9 mRNA to sgRNA from the traditional 1:2 to 1:10, which improves the efficiency of the homozygous mutation of biallelic gene. Here, a MSTNDel73C mutation with FGF5 knockout sheep, in which the MSTN and FGF5 dual-gene biallelic homozygous mutations were produced via the deletion of 3-base pairs of AGC in the third exon of MSTN, resulting in cysteine-depleted at amino acid position 73, and the FGF5 double allele mutation led to inactivation of FGF5 gene. The MSTNDel73C mutation with FGF5 knockout sheep highlights a dominant ‘double-muscle’ phenotype, which can be stably inherited. Both F0 and F1 generation mutants highlight the excellent trait of high-yield meat with a smaller cross-sectional area and higher number of muscle fibers per unit area. Mechanistically, the MSTNDel73C mutation with FGF5 knockout mediated the activation of FOSL1 via the MEK-ERK-FOSL1 axis. The activated FOSL1 promotes skeletal muscle satellite cell proliferation and inhibits myogenic differentiation by inhibiting the expression of MyoD1, and resulting in smaller myotubes. In addition, activated ERK1/2 may inhibit the secondary fusion of myotubes by Ca2+-dependent CaMKII activation pathway, leading to myoblasts fusion to form smaller myotubes.

The objective of this study was using a statistical model to optimize the medium formula and liquid culturing conditions, which was employed to evaluate the potency of pine needles extract as nutritional component in basal medium for culturing Helvella lacunose in order to enhancing the production of mycelia and extracellular polysaccharides (EPS). The most proper carbon and nitrogen source, various fermentation parameters (i.e., initial pH in medium, fermentation time, and temperature) were investigated by single factor test. Based on the experimentation, the optimal concentrations of carbon and nitrogen sources were analyzed by response surface methodology (RSM). The results showed that the optimal medium formula and liquid culturing conditions were 1000 mL pine needles extract, 33.56 g glucose, 4.11 g peptone, 4.06 g YE, 1 g KH2PO4, 1 g NaHCO3, 0.5 g MgSO4, 0.01 g vitamin B1 for the accumulation of mycelial biomass (at pH 6.0, 25°C culturing of 7 days), and EPS (at pH 7.0, 25°C culturing of 10 days). Under optimized medium, the experimental production of mycelia and EPS were 11.78 g/L and 223.16 mg/L, which were 10.52 and 4.85 times than that of control (1.12 ± 0.52 g/L and 46.08 ± 1.18 mg/L, respectively). This data implied that statistical model is very useful tools for optimizing media components and fermentation parameters, and the screened media components and parameters have reference value for further large-scale production.

Abstract Background Alpha 1-antitrypsin (α1-AT) may affect the susceptibility of mastitis in dairy cattle for its possible role in the protection of lactoferrin from proteolytic degradation in the mammary. Milk somatic cell score (SCS) is a logarithmic transformation of the milk somatic cell count widely used as an index to evaluate mastitis. To study the relationships of α1-AT gene and SCS in Chinese Holstein cows, methods of PCR-SSCP, DNA sequencing, PCR-RFLP, and CRS-PCR technologies were used to detect single nucleotide polymorphisms sites in α1-AT gene. Results Two polymorphic sites at G5503A and G5746C of α1-AT gene were found. AA (0.3633), AB (0.4644) and BB (0.1723) genotypes were detected at G5503A site, CC (0.3483), CD (0.4906) and DD (0.1611) genotypes were found at G5746C in Chinese Holstein cows. Least squares mean of SCS for individuals with BB genotype was significantly lower than that with AA and AB genotype (p 0.05). Least squares mean of SCS for individuals with BBDD genotype combination were significantly lower than those with AACC and AACD (p

Different surface properties are needed simultaneously in many applications, especially under an indentation load or impact load. This study proposes one class of novel periodic topological mechanical metamaterials, 2D topological honeycomb structure and 3D topological lattice, whose opposite surfaces have significantly different indentation hardness. The difference of hardness is predicted by theoretical analysis and validated by simulations and experiments, which can be up to 7 times. In comparison with the traditional honeycomb structure with the same parameters, the topological honeycomb structure exhibits higher resistance to indentation loads and it can reduce the influence range and degree of indentation loads at the same time. A design guide of parameters is proposed to achieve a more significant difference of hardness between the opposite surfaces. General design rules at the level of both basic unit piece and lattice structure are proposed, which renders the topological lattice to have outstanding designability to meet different demands in applications. The topological lattice concept will open new avenues to design asymmetric structures and expand the existing design space of mechanical metamaterials. Keywords: Topological lattice, Mechanical metamaterials, Hardness, Indentation, Asymmetric structures

The nucleation of cubic boron nitride (cBN) single crystals synthesized with lithium nitride (Li3N) as a catalyst under high pressure and high temperature (HPHT) was analyzed. Many nanometer-sized cubic boron nitride nuclei formed in the near surface layer, as detected by high resolution transmission electron microscopy. Based on the experiment results, the transformation kinetics is described by a nucleation and growth process in the thermodynamic stability region of cBN. A theoretical description is developed based on the heterogeneous nucleation and layer growth mechanism, and the relevant parameters are estimated and discussed. The critical crystal radius, r*, increases with the temperature under constant pressure; the change with temperature more pronounced at lower pressure (such as 4.5 GPa). The crystal growth velocity increased with the temperature, and it is parabolic with temperature under certain pressure. These results are consistent with experimental data.