Recently, the worldwide supply of rare earth element (REE) resources will be severely restricted. On the other hand, coal fly ash particles emitted from coal-fired electric power plants contain relatively high concent...Recently, the worldwide supply of rare earth element (REE) resources will be severely restricted. On the other hand, coal fly ash particles emitted from coal-fired electric power plants contain relatively high concentrations of REEs. The contents of REEs in coal fly ash are regularly several hundreds of ppmw. In order to extract and recover REEs from coal fly ash particles, as a first step, we have investigated their dissolution behavior in a dilute H2SO4 solvent. The REE content of coal fly ash specimens has been precisely determined, and their presence in the ash component of the original coal and their enrichment in coal fly ash particles during coal combustion have been suggested. REEs in coal fly ash dissolve gradually in H2SO4 over time, and this implies two types of occurrences of the REEs in coal fly ash particles. By applying the unreacted core model to the dissolution behavior of REEs in a H2SO4 solvent, we can explain both types of occurrences.展开更多
Inflammatory stimuli,such as a microbes or lipopolysaccharides,induce a rapid release of neutrophils from the bone marrow and promote neutrophil migration into inflamed sites to promote host defense.However,an excess ...Inflammatory stimuli,such as a microbes or lipopolysaccharides,induce a rapid release of neutrophils from the bone marrow and promote neutrophil migration into inflamed sites to promote host defense.However,an excess accumulation and retention of neutrophils in inflamed tissue can cause severe tissue injuries in the later stages of inflammation.Recent studies have reported that both CXCL12 levels in injured lungs and its receptor,CXCR4,on accumulated neutrophils in injured lungs,increased;furthermore,these studies showed that the CXCL12/CXCR4 signaling pathway participated in neutrophil accumulation in the later stages of lipopolysaccharide(LPS)-induced lung injury.However,the mechanisms underlying this increase in surface CXCR4 expression in neutrophils remain unclear.In this study,we found that surface CXCR4 expression increased in extravascular,but not intravascular,neutrophils in the lungs of LPS-induced lung injury model mice.Furthermore,ex vivo studies revealed that CXCL12 acted not only as a chemoattractant,but also as a suppressor of cell death for the lung neutrophils expressing CXCR4.Sulfatide,one of the native ligands for L-selectin,induced the increase of surface CXCR4 expression on isolated circulating neutrophils,suggesting that the activation of L-selectin may be involved in the increase in surface CXCR4.Our findings show that surface CXCR4 levels on neutrophils increase after extravasation into injured lungs,possibly through the activation of L-selectin.The CXCL12/CXCR4 signaling pathway plays an important role in the modulation of neutrophil activity during acute lung injury,not only by promoting chemotaxis but also by suppressing cell death.展开更多
A numerical simulation shows that by using electronic equalizers 1 bit/s/Hz spectral efficiency can be attained with the same signal quality as a 0.8 bit/s/Hz system. Waveform distortion due to optical band-limiting i...A numerical simulation shows that by using electronic equalizers 1 bit/s/Hz spectral efficiency can be attained with the same signal quality as a 0.8 bit/s/Hz system. Waveform distortion due to optical band-limiting is corrected with nearly 3 dB improvement of the Q-penalty.展开更多
文摘Recently, the worldwide supply of rare earth element (REE) resources will be severely restricted. On the other hand, coal fly ash particles emitted from coal-fired electric power plants contain relatively high concentrations of REEs. The contents of REEs in coal fly ash are regularly several hundreds of ppmw. In order to extract and recover REEs from coal fly ash particles, as a first step, we have investigated their dissolution behavior in a dilute H2SO4 solvent. The REE content of coal fly ash specimens has been precisely determined, and their presence in the ash component of the original coal and their enrichment in coal fly ash particles during coal combustion have been suggested. REEs in coal fly ash dissolve gradually in H2SO4 over time, and this implies two types of occurrences of the REEs in coal fly ash particles. By applying the unreacted core model to the dissolution behavior of REEs in a H2SO4 solvent, we can explain both types of occurrences.
基金grants from the Japanese Society for the Promotion of Science(no.17590776 to HK and no.17790524 to MY).
文摘Inflammatory stimuli,such as a microbes or lipopolysaccharides,induce a rapid release of neutrophils from the bone marrow and promote neutrophil migration into inflamed sites to promote host defense.However,an excess accumulation and retention of neutrophils in inflamed tissue can cause severe tissue injuries in the later stages of inflammation.Recent studies have reported that both CXCL12 levels in injured lungs and its receptor,CXCR4,on accumulated neutrophils in injured lungs,increased;furthermore,these studies showed that the CXCL12/CXCR4 signaling pathway participated in neutrophil accumulation in the later stages of lipopolysaccharide(LPS)-induced lung injury.However,the mechanisms underlying this increase in surface CXCR4 expression in neutrophils remain unclear.In this study,we found that surface CXCR4 expression increased in extravascular,but not intravascular,neutrophils in the lungs of LPS-induced lung injury model mice.Furthermore,ex vivo studies revealed that CXCL12 acted not only as a chemoattractant,but also as a suppressor of cell death for the lung neutrophils expressing CXCR4.Sulfatide,one of the native ligands for L-selectin,induced the increase of surface CXCR4 expression on isolated circulating neutrophils,suggesting that the activation of L-selectin may be involved in the increase in surface CXCR4.Our findings show that surface CXCR4 levels on neutrophils increase after extravasation into injured lungs,possibly through the activation of L-selectin.The CXCL12/CXCR4 signaling pathway plays an important role in the modulation of neutrophil activity during acute lung injury,not only by promoting chemotaxis but also by suppressing cell death.
文摘A numerical simulation shows that by using electronic equalizers 1 bit/s/Hz spectral efficiency can be attained with the same signal quality as a 0.8 bit/s/Hz system. Waveform distortion due to optical band-limiting is corrected with nearly 3 dB improvement of the Q-penalty.
