Due to the biological risks of using the conventional lubricants,the vegetable oils have been considered nowadays.Besides,to improve the tribological properties of the vegetable oils in various applications like metal...Due to the biological risks of using the conventional lubricants,the vegetable oils have been considered nowadays.Besides,to improve the tribological properties of the vegetable oils in various applications like metal forming processes,nanoparticles have been used as additives.This research evaluated the lubrication performance of the Al2O3 and TiO2 nanoparticles dispersed in rapeseed oil during the parallel tubular channel angular pressing (PTCAP) process.The experimental PTCAP tests have been fulfilled under three lubrication conditions and the comparison between the PTCAP processed tubes has been performed in terms of the maximum forming force,surface roughness,and microhardness.The experimental results indicate that adding the mentioned nanoparticles has caused at least a 50% reduction in the maximum deformation load.Moreover,a remarkable decrement in the surface roughness of the formed tubes has been obtained.展开更多
Objective:Among the variousin vitro embryo culture systems,co-culture has demonstrated remarkable effects in pre-implantation embryo development owing to the production of embryo-nourishing factors.Nevertheless,little...Objective:Among the variousin vitro embryo culture systems,co-culture has demonstrated remarkable effects in pre-implantation embryo development owing to the production of embryo-nourishing factors.Nevertheless,little is known about the secretion of these factors.Therefore,in this study,the effect of leukemia inhibitory factor(LIF),one of the most important nourishing factors in the early development of mouse embryos,in human endometrial epithelial cells(hEECs)was evaluated.Methods:Two-cell stage embryos were collected from the oviducts of hyper-stimulated and mated mice and cultivated in a co-culture with an hEEC monolayer with or without LIF.The quality and developmental and attachment potential rates of cultured embryos were evaluated by determining the levels of octamer-binding transcription factor 4(Oct4)and caudal type homeobox 2(Cdx2)transcripts.Results:LIF significantly increased the developmental rate(82.67%vs.61.04%,respectively)and attachment rate(64%vs.45.45%,respectively)of mouse embryos co-cultured with hEECs compared to those in untreated embryos.The expression levels ofOct4 andCdx2 in blastocysts cultured in the presence of LIF were higher than those in blastocysts cultured without LIF.Conclusions:Despite the secretion of LIF by hEECs during co-culture with embryos,the amount of this factor was insufficient,and its addition to the culture media could increase the developmental potential of embryos.展开更多
文摘Due to the biological risks of using the conventional lubricants,the vegetable oils have been considered nowadays.Besides,to improve the tribological properties of the vegetable oils in various applications like metal forming processes,nanoparticles have been used as additives.This research evaluated the lubrication performance of the Al2O3 and TiO2 nanoparticles dispersed in rapeseed oil during the parallel tubular channel angular pressing (PTCAP) process.The experimental PTCAP tests have been fulfilled under three lubrication conditions and the comparison between the PTCAP processed tubes has been performed in terms of the maximum forming force,surface roughness,and microhardness.The experimental results indicate that adding the mentioned nanoparticles has caused at least a 50% reduction in the maximum deformation load.Moreover,a remarkable decrement in the surface roughness of the formed tubes has been obtained.
文摘Objective:Among the variousin vitro embryo culture systems,co-culture has demonstrated remarkable effects in pre-implantation embryo development owing to the production of embryo-nourishing factors.Nevertheless,little is known about the secretion of these factors.Therefore,in this study,the effect of leukemia inhibitory factor(LIF),one of the most important nourishing factors in the early development of mouse embryos,in human endometrial epithelial cells(hEECs)was evaluated.Methods:Two-cell stage embryos were collected from the oviducts of hyper-stimulated and mated mice and cultivated in a co-culture with an hEEC monolayer with or without LIF.The quality and developmental and attachment potential rates of cultured embryos were evaluated by determining the levels of octamer-binding transcription factor 4(Oct4)and caudal type homeobox 2(Cdx2)transcripts.Results:LIF significantly increased the developmental rate(82.67%vs.61.04%,respectively)and attachment rate(64%vs.45.45%,respectively)of mouse embryos co-cultured with hEECs compared to those in untreated embryos.The expression levels ofOct4 andCdx2 in blastocysts cultured in the presence of LIF were higher than those in blastocysts cultured without LIF.Conclusions:Despite the secretion of LIF by hEECs during co-culture with embryos,the amount of this factor was insufficient,and its addition to the culture media could increase the developmental potential of embryos.
