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Objective To provide a guideline for genealogy inference and family lineage investigation through a study of the mismatch tolerance distribution of Y-STR loci in Chinese Han male lineage. Methods Three Han lineages with clear genetic relationships were selected. YFiler Platinum PCR amplification Kit was used to obtain the typing data of 35 Y-STR loci in male samples. The variation of Y-STR haplotypes in generation inheritance and the mismatch tolerance at 1-7 kinship levels were statistically analyzed. Results Mutations in Y-STR were family-specific with different mutation loci and numbers of mutation in different lineages. Among all the mutations, 66.03% were observed on rapidly and fast mutating loci. At 1-7 kinship levels, the number of mismatch tolerance ranged from 0 to 5 on all 35 Y-STR loci, with a maximum step size of 6. On medium and slow mutant loci, the number of mismatch tolerance ranged from 0 to 2, with a maximum step size of 3; on rapidly and fast mutant loci, the number of mismatch tolerance ranged from 0 to 3, with a maximum step size of 6. Conclusion Combined use of SNP genealogy inference and Y-STR lineage investigation, both 0 and multiple mismatch tolerance need to be considered. Family lineage with 0-3 mismatch tolerance on all 35 Y-STR loci and 0-1 mismatch tolerance on medium and slow loci can be prioritized for screening. When the number of mismatch tolerance is eligible, family lineages with long steps should be carefully excluded. Meanwhile, adding fast mutant loci should also be handled with caution.

Overcoming the hardness‐toughness trade‐off in diamonds attracts much interest in physics, chemistry, materials science, and engineering. Recently synthesized nanotwinned diamond composite exhibits massive enhancement in fracture toughness without sacrificing its unprecedented Vickers hardness [Y. Yue et al., Nature 582, 370 (2020)]. Several mechanisms for the toughness enhancement are unveiled based on the edge‐cracked models while the mechanism from Vickers indentation has remained elusive. Here, the energy of nanotwinned diamonds, diamond polytypes, and diamond composites is systematically investigated from Vickers indentation simulation. The results show diamond structures dissipate energy by interface migration, accompanied by the phase transformation from diamond polytypes to the cubic diamond (3C diamond). By tuning the density and distribution of interfaces, the dissipated energy of the diamond is increased to more than twice that of a single‐crystal 3C diamond. This work complements the established mechanisms and provides a universal strategy for toughening diamonds and related materials. [ABSTRACT FROM AUTHOR]

Local scour induced by strong currents has become one of the major challenges for sea-crossing bridges built for the convenience of transportation across bays. To mitigate the local scour of the sea-crossing bridge foundation, this study optimized the design and geometry of the upper part of the skirted caisson and proposed a new type of foundation called the skirted caisson with two tandem piers (SCTTP). Systematic experimental and numerical investigations into the influence of the design parameters of SCTTPs on scour protection were conducted, and the temporal development and mechanism of local scour in SCTTPs were investigated. The following conclusions can be drawn: (1) although the scour of the SCTTP is slightly greater than that of the skirted caisson, the scour terrain of the SCTTP is more stable; (2) the scour of the SCTTP with circular piers is small, and the flat surfaces of semicircular-ended and square piers can intensify the scour; (3) the scour at the front and back of the SCTTP gradually becomes independent of the distance between the two piers, causing the total scour of the SCTTP to increase; and (4) as the width of the tie beam decreases, the scour of the SCTTP with the groove becomes more significant than that of the SCTTP with no groove, but the groove depth has little effect on the maximum scour depth of the SCTTP with the groove. These findings provide insight into the design optimization of SCTTPs from scour. [ABSTRACT FROM AUTHOR]

Objective To screen high-affinity neutralizing antibodies with broad spectrum specificity against different SARS-CoV2 mutants and verify their functions. Methods Balb/c mice were immunized twice with SARS-CoV2 S protein mRNA vaccine coated with liposome, and the specific antibody content in serum was determined. The mice with higher antibody titer were selected for shock immunization. The spleen cells of mice after shock immunization were fused with myeloma cells to prepare fusion cells, and the clones that produces monoclonal antibodies against different parts of S protein were screened by limited dilution and ELISA. Monoclonal antibody was purified and neutral-ization experiments were performed to verify the neutralization activity of the antibody. Monoclonal antibodies with broad spectrum binding properties against recombinant receptor binding domain(RBD) proteins of four SARS-CoV2 mutants were screened by ELISA. Results After twice immunizations, the serum antibody titer against S protein in high dose group 4 was the highest. After shock immunity and cell fusion, 12 hybridoma cell clones with binding activity to S protein were screened, among which 9 strains specifically bound to RBD protein. The neutralization test results showed that the antibodies 41, 46 and 47 had significant neutralization activity in vitro. Compared with the other two antibodies, antibody 46 showed broad-spectrum binding activity to the RBD proteins of four SARS-CoV2 mutants including Omicron. Conclusions Antibody 46 is a broad-spectrum specific neutralizing antibody against four different SARS-CoV2 mutants, which can be further humanized and potentially used for the treatment of COVID-19.