The organization, regulation, and biological functions of the synaptonemal complex.

The synaptonemal complex (SC) is a meiosis-specific proteinaceous macromolecular structure that assembles between paired homologous chromosomes during meiosis in various eukaryotes. The SC has a highly conserved ultrastructure and plays critical roles in controlling multiple steps in meiotic recombination and crossover formation, ensuring accurate meiotic chromosome segregation. Recent studies in different organisms, facilitated by advances in super-resolution microscopy, have provided insights into the macromolecular structure of the SC, including the internal organization of the meiotic chromosome axis and SC central region, the regulatory pathways that control SC assembly and dynamics, and the biological functions exerted by the SC and its substructures.

An Investigation of Microstructural Evolution, Tensile Properties and Work-Hardening Behavior of Nanosized TiB/Al-Cu-Mn Composites.

The microstructure evolution, tensile properties and work-hardening behavior of AA2219 alloy reinforced by in situ nanosized TiB particles were studied in this paper. The observation indicated an impeded recrystallization of the matrix alloy by nanosized TiB particles, and the hybrids of nanosized TiB particles and AlCu phases located at the grain boundary hindered the grain growth. Meanwhile, a large amount fiber textures of <111>//RD (Rolling direction), <110>//RD, <100>//RD <111>//ND (Normal direction), <110>//ND and <100>//ND were detected in nanosized TiB/AA2219 composite.

Hcp/fcc nucleation in bcc iron under different anisotropic compressions at high strain rate: Molecular dynamics study.

Previous researches have revealed the importance of shear and the orientation dependence in the structural transition of iron. In this work, we introduce a series of shear deformations by adjusting the strain ratio between the longitudinal ([001]) and transversal ([010] and [100]) directions, and then investigate this structural transition under different anisotropic compressions with molecular dynamics simulations. It is found that the shear deformation can lower the transition pressure notably, and even change the nucleation structure and morphology.

Effects of temperature and void on the dynamics and microstructure of structural transition in single crystal iron.

With classic molecular dynamics simulations, we investigate the effects of temperature and void on the bcc to hcp/fcc structural transition in single crystal iron driven by 1D ([0 0 1]) and 3D (uniform) compressions. The results show that the pressure threshold does not reduce monotonously with temperature. The pressure threshold firstly increases and then decreases in the range of 60-360 K under 1D compression, while the variation trend is just opposite under 3D compression.

Antibacterial constituents from Antarctic fungus, Aspergillus sydowii SP-1.

One new alkaloid, named as acremolin C (1), was isolated from static culture of Antarctic fungus, Aspergillus sydowii SP-1, in an investigation of the antimicrobial constituents of this Antarctic microorganism, and its structure was determined by spectroscopic methods. Additionally, four known compounds, cyclo-(L-Trp-L-Phe) (2), 4-hydroxyphenylacetic acid (3), (7S)-(+)-hydroxysydonic acid (4) and (7S, 11S)-(+)-12-hydroxysydonic acid (5), were isolated and identified. Biological studies disclosed that compounds 2, 4 and 5 showed moderate inhibitions against methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-resistant Staphylococcus epidermidis (MRSE) as comparing to tigecycline, while compound 1 displayed weak inhibition activities against MRSA and MRSE.

[Genetic scanning on chromosome 8 loci for coronary heart disease].

At present, genome-wide association study on coronary heart disease (CHD) has been carried out in several major medical research centers worldwide. Most studies of CHD susceptibility loci or regions focused on chromosome 1, 3, 9, 11 and 16, while studies on chromosome 8 are rare. To the best of our knowledge, the genome study on chromosome 8 about CHD in Chinese Han population has never been reported before.

[Clinical observation on extensor weakness after total knee arthroplasty for severe flexion deformity knees].

Objective: To find out the reasons of extensor weakness after total knee arthroplasty for severe flexion deformity knees, and the rehabilitation method.

Methods: From January 2001 to January 2004, 30 knees (20 cases) with severe flexion deformity were performed total knee arthroplasty with PS prosthesis, and the follow up were at least 6 months (6 to 40 months, average 18 months). All cases in this group were classified with the extensor force grade and were given certain exercises according to the grade.