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ABSTRACTAfter fertilization, highly differentiated sperm and oocyte are reprogrammed to totipotent embryo, which subsequently cleavages and develops into an individual through spatial-temporal differentiation. Histone modifications play critical roles to coordinate with other reprogramming events in early stages of embryogenesis. However, most of studies focus on modifications at N-terminus of histones, those at nucleosome core were not well understood. Here, we characterize the three key acetylation events in the histone H3 core, H3K56/K64/K122ac, in early human embryos. The three residues localize at DNA entry-exit position of the nucleosome. Globally, H3K56ac, H3K64ac and H3K122ac were detectable throughout preimplantation stages, with H3K64ac levels being relatively stronger and H3K122ac levels being much weaker. Besides, H3K56ac level had a peak at two-cell stage. Moreover, we found that LINEs also peak at two-cell stage, and H3K56ac was enriched at young LINE-1 in human ESCs, supporting that H3K56ac is an important driving force for young LINE-1 activation in human preimplantation embryos. Our results suggest that acetylation in the nucleosome core of histone H3 is dynamic and various during preimplantation development, and may drive diverse chromatin remodeling events in this developmental window.

ABSTRACTRing1 and Yin Yang 1-Binding Protein (RYBP) is a member of non-canonical polycomb repressive complex 1 to mediate monoubiquitination of histone H2A at lysine 119. It plays an important role in development, but its role in reproduction remains illusive. In this study, we used Rybp conditional knockout mouse model to genetically ablate Rybp in male germ cells. We found that Rybp deficiency during spermatogenesis led to smaller testes, loss of germline cells, disturbed meiosis, increased apoptosis of spermatocytes, decreased sperm motility, and reduced global H3K9me3, without impacting retrotransposon expression. Meanwhile, we depleted Rybp during oogenesis, but oocyte maturation and preimplantation development were normal. Our findings demonstrate that RYBP plays important roles in spermatogenesis through regulating meiosis and sperm motility.

Co2FeAl full-Hesuler alloys show good soft magnetic properties, implying a promising high ferromagnetic resonance frequency. In this study, Co2FeAl films were deposited on Si (100) substrates using an oblique sputtering method. As expected, a good high-frequency performance was achieved in the as-deposited Co2FeAl films without any annealing. An obvious uniaxial magnetic anisotropy over 200 Oe with the magnetic hard axis along the radial direction of the sample turntable was obtained. As a result, the self-bias ferromagnetic resonance frequency reaches more than 4 GHz for the Co2FeAl films prepared under an integrated circuits compatible process. These results indicate that the Co2FeAl films are promising in integrated circuits RF/microwave devices.

A series of (Co2FeSi)1-x(Al2O3)x Heusler alloy films with various Al2O3-doping were prepared by an oblique sputtering method. It is exciting that the as-deposited films exhibit a very high in-plane uniaxial magnetic anisotropy (UMA) field up to 360 Oe and low coercivity of 12 Oe. Consequently, a very high self-bias ferromagnetic resonance frequency in excess of 5.02 GHz was obtained in as-deposited Co2FeSi films without any annealing. The good microwave ferromagnetic performances and the integrated circuits compatible fabrication process of Co2FeSi films make possible application in RF/microwave devices.

The room-temperature magnetocaloric effect (MCE) of Cox(MnSb)1-x (x=0.07, 0.15, 0.24) alloys has been investigated. It is revealed that the Curie temperature TC and the magnetic entropy change ΔSM are sensitive to the Co content x. When x=0.15, the MCE of Co0.15(MnSb)0.85 alloy is optimal with ΔSM=1.8 J/kg.K at 324 K under an applied magnetic field of 3 T. A second-order phase transformation occurs around TC, and the magnetic hysteresis loss thermal lag is negligible. These features demonstrate that Co0.15(MnSb)0.85 alloy is a promising room-temperature magnetocaloric materials.

In the past decades, an increasing number of surgeons started using posterior vertebral column resection (PVCR) to treat severe, rigid and angular spinal deformities. Little high-level evidence is available to guide surgical treatment. The aims of our study were to identify important surgical strategies and key technical points of Chinese experts who have extensive experience in the management of severe, rigid and angular spinal deformities using PVCR, and to standardize and unify the current core concepts. Workgroups of consensus were formed by selecting nationwide representing experts and comprehensive consultations. Eight task forces for major issues were established, then retrieval of literature, collection of expert opinions and writing of review articles were carried out. A modified Delphi process was chosen in round-table forum with three face-to-face meetings. Consensus was reached with items graded more than seven points including: indications and contraindications of PVCR; review PVCR in the evolution of spinal osteotomies; The corrective mechanism and safety of spinal cord; monitoring and responses of spinal cord crisis; characteristics and therapeutic outcome of pulmonary function; management of bleeding during PVCR; relationship of pedicle screw insertion and spinal cord safety; and analysis of non-neurologic complications and prevention strategies. In conclusion, The essential properties regarding PVCR procedure are tightly linked with various factors such as medical and surgical indication, range and level of vertebral column resection, strategies of correction, corrective efficiency and control of neurological risk. PVCR is used mainly for severe, rigid spinal deformity that is not manageable by other osteotomy techniques.