Human in vitro fertilization (IVF) embryos usually have developmental block at 4-8 cell stages,in which only 30％-50％ percent of IVF embryos develop to blastocyst *** is the main cause for low efficiency and repeated...
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Human in vitro fertilization (IVF) embryos usually have developmental block at 4-8 cell stages,in which only 30％-50％ percent of IVF embryos develop to blastocyst *** is the main cause for low efficiency and repeated treatment failure in human fertility *** factor CDX2 is one of the key genes in human early embryonic development,which decides the differentiation from blastomere to trophoblastic ***,the relationship between the developmental block of human IVF embryos and CDX2 is poorly *** this study,we showed that CDX2 is crucial for human IVF embryonic development.q-PCR analysis confirmed that the level of CDX2 in developmental block embryos was dramatically *** analysis further demonstrated that CDX2 protein level in developmental block embryos was significantly decreased compared with that in control *** also addressed whether reexpression of CDX2 could rescue developmental block defects in human IVF developmental block *** expected,these developmental block defects could be partially rescued by overexpression of CDX2 *** conclusion,these findings suggest that CDX2 plays an important role in the process of human early embryonic development.
Multi-hop relay can effectively improve the average packet loss rate (PLR) of vehicular ad hoc networks within a particular zone of interest. Challenges arise from analyzing the average PLR affected by distributed rel...
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Multi-hop relay can effectively improve the average packet loss rate (PLR) of vehicular ad hoc networks within a particular zone of interest. Challenges arise from analyzing the average PLR affected by distributed relay selections, which depend on the mobility of vehicles, the wireless channel conditions, and media access control (MAC). In this letter, we propose an average PLR analysis model taking into account the above three factors. However, the closed-form expression for the average PLR is intractable mainly due to the multiple integral of the joint distance distribution integrating with the channel conditions and vehicle mobility. An explicit expression for the upper bound of the average PLR is obtained by using Taylor series expansion, Holder's inequality, and the relay probability relaxation, which can facilitate the selection of the parameters at the physical and MAC layers for a better PLR. Simulation results validate our analyses.
Aeromonas hydrophila (A. hydrophila) is an opportunistic pathogen of fish-human-livestock, which poses a threat to the development of aquaculture. Lytic phage has long been considered as an effective bactericidal agen...
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Aeromonas hydrophila (A. hydrophila) is an opportunistic pathogen of fish-human-livestock, which poses a threat to the development of aquaculture. Lytic phage has long been considered as an effective bactericidal agent. However, the rapid development of phage resistance seriously hinders the continuous application of lytic phages. In our study, a new bacteriophage vB_ AhaP_PZL-Ah8 was isolated from sewage and its characteristics and genome were investigated. Phage vB_ AhaP_PZL-Ah8 has been classified as the member of the Podoviridae family, which exhibited the latent period was about 30 min. As revealed from the genomic sequence analysis, vB_ AhaP_PZL-Ah8 covered a double-stranded genome of 40,855 bp (exhibiting 51.89% G + C content), with encoding 52 predicted open reading frames (ORFs). The results suggested that the combination of vB_ AhaP_PZLAh8 and another A. hydrophila phage vB_ AhaP_PZL-Ah1 could improve the therapeutic efficacy both in vitro and in vivo. The resistance mutation frequency of A. hydrophila cells infected with the mixture phage (vB_ AhaP_PZLAh8+ vB_ AhaP_PZL-Ah1) was significantly lower than cells treated with single phage (P < 0.01). Phage therapy in vivo showed that the survival rate in the mixture phage treatment group was significantly higher than that in single phage treatment group.
A see-through head-mounted display (HMD) is demonstrated in the paper, which can present the user with information such as virtual symbols or images superimposed over real-world image. To meet the human eyes’ visual ...
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Overcoming the toughness inadequacy of Al-Li alloys is in urgent need for developing new low-density and high-performance aerospace aluminum alloys. In this research, continuous equal-channel angular pressing (ECAP) a...
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Overcoming the toughness inadequacy of Al-Li alloys is in urgent need for developing new low-density and high-performance aerospace aluminum alloys. In this research, continuous equal-channel angular pressing (ECAP) and post-aging were developed to significantly enhance the impact toughness of 1420 Al-Li alloy. The effects of the processes on microstructure evolution, impact absorbed energy and fracture surfaces of 1420 alloy were investigated. The results demonstrated that the impact toughness of ultrafine-grained (UFG) 1420 alloy after 8 ECAP passes at 573 K reached up to 26.6 J/cm(2) at room temperature and increased sixfold compared with that of the coarse-grained sample, but the post-aging reduced the beneficial effect. The remarkable improvement after the warm ECAP was mainly due to the UFG microstructure, certain amount of dislocations, and the fine precipitates with uniform distribution, thereby making UFG 1420 alloys more attractive in aerospace applications.
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