Macro-mesoporous γ-alumina support（MMA） was prepared by a sol-gel route in aqueous medium using pseudo-boehmite as aluminum source and polystyrene microspheres and Pluronic P123 as hard and soft dual templates,resp...Macro-mesoporous γ-alumina support（MMA） was prepared by a sol-gel route in aqueous medium using pseudo-boehmite as aluminum source and polystyrene microspheres and Pluronic P123 as hard and soft dual templates,respectively.MMA had a BET specific surface area of about 259 m2 g-1,total pore volume of about 1.61 cm3 g-1,macropore diameter of about 102 nm,and mesopore diameter of about 14 nm.Re2O7/MMA and conventional Re2O7/Al2O3 were prepared by a incipient-wetness impregnation method,and their catalytic performances in the metathesis of 1-butene and 2-butene were tested in a fixed-bed tubular reactor.The result showed that Re2O7/MMA possessed higher activity and far longer working life-span than conventional Re2O7/Al2O3.展开更多
Mesoporous γ-aluminas with large pore size （up to 19 nm, denoted as MAI9） are prepared from dispersed pseudo-boehmite using pluronic P123 as template. It is found that these mesoporous alumina supported rhenium oxi...Mesoporous γ-aluminas with large pore size （up to 19 nm, denoted as MAI9） are prepared from dispersed pseudo-boehmite using pluronic P123 as template. It is found that these mesoporous alumina supported rhenium oxide catalysts were more active and have far longer working life-span in gas-phase metathesis of 1-butene and 2-butene to propene than rhenium oxide on conventional alumina with small pore size （5 nm）. At 60 ℃ and atmospheric pressure with WHSV = 1 h^-1, the similar stable conversions of butene （ca. 55%） for all the 13 wt% Re207/alumina catalysts were obtained near the chemical equilibrium, and the stable working life-spans of Re2OT/MA19 were far longer than that of Re2O7/A1203, being about 70 h and 20 h, respectively.展开更多
High Voltage Direct Current (HVDC) electric power transmission is a promising technology for integrating offshore wind farms and interconnecting power grids in different regions. In order to maintain the DC voltage, d...High Voltage Direct Current (HVDC) electric power transmission is a promising technology for integrating offshore wind farms and interconnecting power grids in different regions. In order to maintain the DC voltage, droop control has been widely used. Transmission line loss constitutes an import part of the total power loss in a multi-terminal HVDC scheme. In this paper, the relation between droop controller design and transmission loss has been investigated. Different MTDC layout configurations are compared to examine the effect of droop controller design on the transmission loss.展开更多
Industrial CO_(2)electroreduction has received tremendous attentions for resolution of the current energy and environmental crisis,but its performance is greatly limited by mass transport at high current density.In th...Industrial CO_(2)electroreduction has received tremendous attentions for resolution of the current energy and environmental crisis,but its performance is greatly limited by mass transport at high current density.In this work,an ion‐polymer‐modified gas‐diffusion electrode is used to tackle this proton limit.It is found that gas diffusion electrode‐Nafion shows an impressive performance of 75.2%Faradaic efficiency in multicarbon products at an industrial current density of 1.16 A/cm^(2).Significantly,in‐depth electrochemical characterizations combined with in situ Raman have been used to determine the full workflow of protons,and it is found that HCO_(3)^(−)acts as a proton pool near the reaction environment,and HCO_(3)^(−)and H_(3)O^(+)are local proton donors that interact with the proton shuttle−SO_(3)^(−)from Nafion.With rich proton hopping sites that decrease the activation energy,a“Grotthuss”mechanism for proton transport in the above system has been identified rather than the“Vehicle”mechanism with a higher energy barrier.Therefore,this work could be very useful in terms of the achievement of industrial CO_(2)reduction fundamentally and practically.展开更多
microRNAs （miRNAs） are a class of non-coding RNAs that function as endogenous triggers of the RNA interference pathway. Studies have shown that thousands of human protein-coding genes are regulated by miRNAs, indica...microRNAs （miRNAs） are a class of non-coding RNAs that function as endogenous triggers of the RNA interference pathway. Studies have shown that thousands of human protein-coding genes are regulated by miRNAs, indicating that miRNAs are master regulators of many important biological processes, such as cancer development, miRNAs frequently have deregulated expression in many types of human cancers, and play critical roles in tumorigenesis, which functions either as tumor suppressors or as oncogenes. Recent studies have shown that miRNAs are highly related with cancer progression, including initiating, growth, apoptosis, invasion, and metastasis. Furthermore, miRNAs are shown to be responsible for the cancer-related inflam- mation, anti-cancer drug resistance, and regulation of cancer stem ceils. Therefore, miRNAs have generated great interest as a novel strategy in cancer diagnosis and therapy. Here we review the versatile roles of miRNAs in cancers and their potential applications for diagnosis, prognosis, and treatment as biomarkers.展开更多
Objective To probe into the prelude marker of central nervous system injury in response to methyl mercury chloride （MMC） stimulation and the signal transduction molecular mechanism of injury in rat brain induced by ...Objective To probe into the prelude marker of central nervous system injury in response to methyl mercury chloride （MMC） stimulation and the signal transduction molecular mechanism of injury in rat brain induced by MMC. Methods The expression of c-fos mRNA in brain and the expression of c-FOS protein in cortex, hippocampus and ependyma were observed using reverse transcription polymerase chain reaction （RT-PCR） and immunocytochemical methods. The control group was injected with physiological saline of 0.9%, while the concentrations for the exposure groups were 0.05 and 0.5, 5 mg/kg MMC respectively, and the sampling times points were 20, 60, 240, 1440 min. Results The expression of c-FOS protein in cortex and hippocampus increased significantly, the accumulation of mercury in the brain induced by 0.05 mg/Kg MMC for 20 min had no significant difference compared with the control group. The mean value was 0.0044 mg/Kg, while the protein c-FOS expression had significant difference compared with the control group （P〈0.01）. More sensitive expression occurred in hippocampus and cortex, but not in ependyma. Conclusion The expression of c-FOS protein in cortex and hippocampus can predict the neurotoxicity of MMC in the early time, and immediately early gene （lEG） c-fos participates in the process of brain injury induced by MMC.展开更多
Objective:Recent research has indicated that altered promoter methylation of oncogenes and tumor suppressor genes is an important mechanism in lung cancer development and progression.In this study,we investigated the ...Objective:Recent research has indicated that altered promoter methylation of oncogenes and tumor suppressor genes is an important mechanism in lung cancer development and progression.In this study,we investigated the association between promoter methylation of TMEM88,a possible inhibitor of the Wnt/β-Catenin signaling,and the survival of patients with nonsmall cell lung cancer(NSCLC).Methods:Twelve pairs of tumor and adjacent non-tumor samples were used for microarray analyses of DNA methylation and gene expression.For validation,more than two hundred additional samples were analyzed for methylation using bisulfite pyrosequencing and for gene expression using q RT-PCR.Then the cell function were tested by wound healing,transwell,CCK8 and cell cycle assay.Results:Our analysis of patient specimens showed that TMEM88 methylation was higher in NSCLC tumors(82.2%±10.3,P<0.01)compared with the adjacent normal tissues(65.9%±7.2).The survival analysis revealed that patients with high TMEM88methylation had a shorter overall survival(46 months)compared with patients with low TMEM88 methylation(>56 months;P=0.021).In addition,we found that demethylation treatment could inhibit tumor cell proliferation,migration,and invasion,which was supportive of an association between methylation and survival.Conclusions:Based on these consistent observations,we concluded that TMEM88 may play an important role in NSCLC progression and that promoter methylation of TMEM88 may serve as a biomarker for NSCLC prognosis and treatment.展开更多
Cabbage(Brassica oleracea var.capitata)is a biennial plant with strong self-incompatibility and an obligate requirement for prolonged vernalization by exposure to low temperatures to induce flowering.These characteris...Cabbage(Brassica oleracea var.capitata)is a biennial plant with strong self-incompatibility and an obligate requirement for prolonged vernalization by exposure to low temperatures to induce flowering.These characteristics significantly increase the difficulty of exploiting novel germplasm induced by physical or chemical mutagens.In this study,we report a CRISPR/Cas9 gene-editing system based on endogenous tRNA processing to induce high efficiency and inheritable mutagenesis in cabbage.Using the phytoene desaturase gene BoPDS,the S-receptor kinase gene BoSRK,and the male-sterility-associated gene BoMS1 as the target genes,multisite and multiple gene mutations were achieved using a construct with tandemly arrayed tRNA-sgRNA architecture to express multiple sgRNAs.The BoSRK3 gene mutation suppressed self-incompatibility completely,converting the self-incompatible line into a self-compatible line.In addition,the BoMS1 gene mutation produced a completely male-sterile mutant,which was highly cross compatible with its nonmutant isoline at the flowering stage as a result of a simultaneous BoSRK3 gene mutation,enabling the economic propagation of the male-sterile line through bee-mediated cross-pollination.Interestingly,higher site mutation efficiency was detected when a guide sequence was inserted into a location in the tandemly arrayed tRNA-sgRNA architecture that was distal from the upstream Pol III promoter.In addition,mutation sites were also detected in the paralogous genes of the BoPDS and BoSRK genes that had fully consistent sequences or base mismatches but beyond the“seed”region in the spacer sequence compared with the target sgRNAs.Collectively,our results demonstrate that the CRISPR/Cas9 system,coupled with an endogenous tRNA-processing system,is an efficient tool to improve cabbage traits.展开更多
基金supported by the National Natural Science Foundation of China (Grant No:20976192)SINOPEC Jiujiang Petrochemical Company (G2810-09-ZS-0027)
文摘Macro-mesoporous γ-alumina support（MMA） was prepared by a sol-gel route in aqueous medium using pseudo-boehmite as aluminum source and polystyrene microspheres and Pluronic P123 as hard and soft dual templates,respectively.MMA had a BET specific surface area of about 259 m2 g-1,total pore volume of about 1.61 cm3 g-1,macropore diameter of about 102 nm,and mesopore diameter of about 14 nm.Re2O7/MMA and conventional Re2O7/Al2O3 were prepared by a incipient-wetness impregnation method,and their catalytic performances in the metathesis of 1-butene and 2-butene were tested in a fixed-bed tubular reactor.The result showed that Re2O7/MMA possessed higher activity and far longer working life-span than conventional Re2O7/Al2O3.
基金financially supported by SINOPEC Jiujiang Petrochemical Company and from the National Nature Science Foundation of China (No.20976192)
文摘Mesoporous γ-aluminas with large pore size （up to 19 nm, denoted as MAI9） are prepared from dispersed pseudo-boehmite using pluronic P123 as template. It is found that these mesoporous alumina supported rhenium oxide catalysts were more active and have far longer working life-span in gas-phase metathesis of 1-butene and 2-butene to propene than rhenium oxide on conventional alumina with small pore size （5 nm）. At 60 ℃ and atmospheric pressure with WHSV = 1 h^-1, the similar stable conversions of butene （ca. 55%） for all the 13 wt% Re207/alumina catalysts were obtained near the chemical equilibrium, and the stable working life-spans of Re2OT/MA19 were far longer than that of Re2O7/A1203, being about 70 h and 20 h, respectively.
文摘High Voltage Direct Current (HVDC) electric power transmission is a promising technology for integrating offshore wind farms and interconnecting power grids in different regions. In order to maintain the DC voltage, droop control has been widely used. Transmission line loss constitutes an import part of the total power loss in a multi-terminal HVDC scheme. In this paper, the relation between droop controller design and transmission loss has been investigated. Different MTDC layout configurations are compared to examine the effect of droop controller design on the transmission loss.
基金National Key R&D Program of China,Grant/Award Number:2021YFF0500700Fundamental Research Funds for the Central Universities,Grant/Award Numbers:30921013103,30920041113+1 种基金Jiangsu Natural Science Foundation,Grant/Award Number:BK20190460National Natural Science Foundation of China,Grant/Award Numbers:51888103,52006105,92163124。
文摘Industrial CO_(2)electroreduction has received tremendous attentions for resolution of the current energy and environmental crisis,but its performance is greatly limited by mass transport at high current density.In this work,an ion‐polymer‐modified gas‐diffusion electrode is used to tackle this proton limit.It is found that gas diffusion electrode‐Nafion shows an impressive performance of 75.2%Faradaic efficiency in multicarbon products at an industrial current density of 1.16 A/cm^(2).Significantly,in‐depth electrochemical characterizations combined with in situ Raman have been used to determine the full workflow of protons,and it is found that HCO_(3)^(−)acts as a proton pool near the reaction environment,and HCO_(3)^(−)and H_(3)O^(+)are local proton donors that interact with the proton shuttle−SO_(3)^(−)from Nafion.With rich proton hopping sites that decrease the activation energy,a“Grotthuss”mechanism for proton transport in the above system has been identified rather than the“Vehicle”mechanism with a higher energy barrier.Therefore,this work could be very useful in terms of the achievement of industrial CO_(2)reduction fundamentally and practically.
基金supported by National Natural Science Foundation of China grants (No. 30872889, 81072215, 81001210, 81172580)Scientific Research Foundation for the Returned Overseas Chinese Scholars, State Education Ministry (No. 20098-8-2)+1 种基金State Key Laboratory of Oral Diseases Open Funding (SKLODOF2010-05)the Fundamental Research Funds of the Central Universities of China (2011)
文摘microRNAs （miRNAs） are a class of non-coding RNAs that function as endogenous triggers of the RNA interference pathway. Studies have shown that thousands of human protein-coding genes are regulated by miRNAs, indicating that miRNAs are master regulators of many important biological processes, such as cancer development, miRNAs frequently have deregulated expression in many types of human cancers, and play critical roles in tumorigenesis, which functions either as tumor suppressors or as oncogenes. Recent studies have shown that miRNAs are highly related with cancer progression, including initiating, growth, apoptosis, invasion, and metastasis. Furthermore, miRNAs are shown to be responsible for the cancer-related inflam- mation, anti-cancer drug resistance, and regulation of cancer stem ceils. Therefore, miRNAs have generated great interest as a novel strategy in cancer diagnosis and therapy. Here we review the versatile roles of miRNAs in cancers and their potential applications for diagnosis, prognosis, and treatment as biomarkers.
基金This work was supported by National Natural Science Foundation of China (20177013 40303013) and the Chinese Academy ofSciences for Key and Innovation Projects (KZCX-SW-437).
文摘Objective To probe into the prelude marker of central nervous system injury in response to methyl mercury chloride （MMC） stimulation and the signal transduction molecular mechanism of injury in rat brain induced by MMC. Methods The expression of c-fos mRNA in brain and the expression of c-FOS protein in cortex, hippocampus and ependyma were observed using reverse transcription polymerase chain reaction （RT-PCR） and immunocytochemical methods. The control group was injected with physiological saline of 0.9%, while the concentrations for the exposure groups were 0.05 and 0.5, 5 mg/kg MMC respectively, and the sampling times points were 20, 60, 240, 1440 min. Results The expression of c-FOS protein in cortex and hippocampus increased significantly, the accumulation of mercury in the brain induced by 0.05 mg/Kg MMC for 20 min had no significant difference compared with the control group. The mean value was 0.0044 mg/Kg, while the protein c-FOS expression had significant difference compared with the control group （P〈0.01）. More sensitive expression occurred in hippocampus and cortex, but not in ependyma. Conclusion The expression of c-FOS protein in cortex and hippocampus can predict the neurotoxicity of MMC in the early time, and immediately early gene （lEG） c-fos participates in the process of brain injury induced by MMC.
基金supported by the National Natural Science Foundation of China(Grant No.81573231)the Medical Professionals Crossing Project of Shanghai Jiao Tong University(Grant No.YG2015ZD01)
文摘Objective:Recent research has indicated that altered promoter methylation of oncogenes and tumor suppressor genes is an important mechanism in lung cancer development and progression.In this study,we investigated the association between promoter methylation of TMEM88,a possible inhibitor of the Wnt/β-Catenin signaling,and the survival of patients with nonsmall cell lung cancer(NSCLC).Methods:Twelve pairs of tumor and adjacent non-tumor samples were used for microarray analyses of DNA methylation and gene expression.For validation,more than two hundred additional samples were analyzed for methylation using bisulfite pyrosequencing and for gene expression using q RT-PCR.Then the cell function were tested by wound healing,transwell,CCK8 and cell cycle assay.Results:Our analysis of patient specimens showed that TMEM88 methylation was higher in NSCLC tumors(82.2%±10.3,P<0.01)compared with the adjacent normal tissues(65.9%±7.2).The survival analysis revealed that patients with high TMEM88methylation had a shorter overall survival(46 months)compared with patients with low TMEM88 methylation(>56 months;P=0.021).In addition,we found that demethylation treatment could inhibit tumor cell proliferation,migration,and invasion,which was supportive of an association between methylation and survival.Conclusions:Based on these consistent observations,we concluded that TMEM88 may play an important role in NSCLC progression and that promoter methylation of TMEM88 may serve as a biomarker for NSCLC prognosis and treatment.
基金the National Key Research and Development Program of China(2017YFD0101804)the Science and Technology Innovation Program for the Social Undertakings and the People's Livelihood in Chongqing(cstc2015shms-ztzx80005,cstc2015shms-ztzx80007,cstc2015shms-ztzx80009)for their financial support.
文摘Cabbage(Brassica oleracea var.capitata)is a biennial plant with strong self-incompatibility and an obligate requirement for prolonged vernalization by exposure to low temperatures to induce flowering.These characteristics significantly increase the difficulty of exploiting novel germplasm induced by physical or chemical mutagens.In this study,we report a CRISPR/Cas9 gene-editing system based on endogenous tRNA processing to induce high efficiency and inheritable mutagenesis in cabbage.Using the phytoene desaturase gene BoPDS,the S-receptor kinase gene BoSRK,and the male-sterility-associated gene BoMS1 as the target genes,multisite and multiple gene mutations were achieved using a construct with tandemly arrayed tRNA-sgRNA architecture to express multiple sgRNAs.The BoSRK3 gene mutation suppressed self-incompatibility completely,converting the self-incompatible line into a self-compatible line.In addition,the BoMS1 gene mutation produced a completely male-sterile mutant,which was highly cross compatible with its nonmutant isoline at the flowering stage as a result of a simultaneous BoSRK3 gene mutation,enabling the economic propagation of the male-sterile line through bee-mediated cross-pollination.Interestingly,higher site mutation efficiency was detected when a guide sequence was inserted into a location in the tandemly arrayed tRNA-sgRNA architecture that was distal from the upstream Pol III promoter.In addition,mutation sites were also detected in the paralogous genes of the BoPDS and BoSRK genes that had fully consistent sequences or base mismatches but beyond the“seed”region in the spacer sequence compared with the target sgRNAs.Collectively,our results demonstrate that the CRISPR/Cas9 system,coupled with an endogenous tRNA-processing system,is an efficient tool to improve cabbage traits.
