Betula platyphylla Sukaczev tetraploids have significantly larger leaf, fruit and stoma (gigantic phenotype) than diploids of the same species;however, the mechanism underlying this difference remains unclear. Tetrapl...Betula platyphylla Sukaczev tetraploids have significantly larger leaf, fruit and stoma (gigantic phenotype) than diploids of the same species;however, the mechanism underlying this difference remains unclear. Tetraploid B. platyphylla transcriptome data have indicated that the expression of genes related to indole-3-acetic acid (IAA) biosynthesis and signal transduction was altered after genome duplication. IAA exerts pleiotropic effects on growth and development by inducing the expression of Aux/IAA. We identified 20 Aux/IAA genes (BpIAA1– BpIAA20) in B. platyphylla distributed across 10 chromosomes. Multiple alignment and motif analyses revealed that nine BpIAA proteins shared all four conserved domains. Phylogenetic analysis indicated that Aux/IAA families were divided into four subfamilies and that there were two pairs of BpIAA sister genes. The BpIAAs were differentially expressed in diploids and tetraploids. Moreover, the expression levels of the nine BpIAA genes were specifically up-regulated in tetraploids from June to September compared with May (except August 5th) in tetraploids, while they were down-regulated in diploids. IAA levels were more than twofold higher in tetraploids than diploids during the vegetative season. These results indicate that genome duplication of B. platyphylla caused the up-regulated of genes involved in IAA synthesis, and the increased concentration of IAA may induce the constitutive expression of 20 BpIAA genes. Therefore, the significant changes in the expression patterns of the BpIAAs contributed to the gigantic phenotype of tetraploids to some extent. Our research sheds light on the phenotypic variations observed in B. platyphylla tetraploids.展开更多
The development of low-cost,high-performance catalysts at the atomic scale has become a challenging issue for the large-scale applications of renewable clean energy technologies.Herein,on the basis of density function...The development of low-cost,high-performance catalysts at the atomic scale has become a challenging issue for the large-scale applications of renewable clean energy technologies.Herein,on the basis of density functional theory calculation,we systematically investigate the effect of the local environment on the activity and selectivity of electrochemical carbon dioxide reduction reaction over single/multi-atom alloy clusters formed by the transition metal(Fe,Co,and Ni)-doped Cu13/55 clusters.Our findings reveal that the catalytic performance of multi-atom alloy clusters far exceeds that of Cu(211)surface.Notably,the Co666 configuration exhibits exceptional performance with a remarkably low free energy barrier of just 0.33 eV.Furthermore,our investigations demonstrate that catalytic performance is predominantly determined by the relative proportion of modifying metallic dopant species that generate a coordination number of 6.This ratio principally influences the adsorption strength of key intermediates(HCOO*and H2COO*).Bader charge analyses and free energy calculations elucidate a new mechanistic pathway,wherein the hydrogenation of CO_(2)at C-sites catalyzes the reduction of CO_(2)to CH_(4).This theoretical research provides valuable insights into the fundamental processes and energy landscapes involved in converting CO_(2)to CH_(4)on the studied catalytic structure,potentially paving the way for more efficient and sustainable carbon dioxide utilization strategies.展开更多
A combined treatment technology （DEF-BIO） using the direct electro-Fenton （DEF） process and bioremediation （BIO） was established in this study. The performance of the DEF-BIO process on the remediation of a pyre...A combined treatment technology （DEF-BIO） using the direct electro-Fenton （DEF） process and bioremediation （BIO） was established in this study. The performance of the DEF-BIO process on the remediation of a pyrene （PYR）-contaminated soil was evaluated in a slurry reactor. The appropriate order of application was to conduct the DEF process followed by BIO, evaluated through analysis of the degradation characteristics of each process individually. In addition, the application time of the DEF process affected the efficiency of the combined process. The optimum time to apply the DEF process was determined through an analysis of the induced changes in PYR intermediates, pH, soil organic matter （SOM） and bacteria. The optimum application time of the DEF process was 6 h. All the induced changes were beneficial for the BIO phase. The removal of PYR was 91.02% for DEF- BIO after 72h, and the efficiency was almost 50% increased, compared with the individual DEF and BIO treatments. Therefore, the combined process of DEF-BIO process may be an efficient and promising method for the remediation.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.31370660 and 31670673)the 111 Project(B16010)
文摘Betula platyphylla Sukaczev tetraploids have significantly larger leaf, fruit and stoma (gigantic phenotype) than diploids of the same species;however, the mechanism underlying this difference remains unclear. Tetraploid B. platyphylla transcriptome data have indicated that the expression of genes related to indole-3-acetic acid (IAA) biosynthesis and signal transduction was altered after genome duplication. IAA exerts pleiotropic effects on growth and development by inducing the expression of Aux/IAA. We identified 20 Aux/IAA genes (BpIAA1– BpIAA20) in B. platyphylla distributed across 10 chromosomes. Multiple alignment and motif analyses revealed that nine BpIAA proteins shared all four conserved domains. Phylogenetic analysis indicated that Aux/IAA families were divided into four subfamilies and that there were two pairs of BpIAA sister genes. The BpIAAs were differentially expressed in diploids and tetraploids. Moreover, the expression levels of the nine BpIAA genes were specifically up-regulated in tetraploids from June to September compared with May (except August 5th) in tetraploids, while they were down-regulated in diploids. IAA levels were more than twofold higher in tetraploids than diploids during the vegetative season. These results indicate that genome duplication of B. platyphylla caused the up-regulated of genes involved in IAA synthesis, and the increased concentration of IAA may induce the constitutive expression of 20 BpIAA genes. Therefore, the significant changes in the expression patterns of the BpIAAs contributed to the gigantic phenotype of tetraploids to some extent. Our research sheds light on the phenotypic variations observed in B. platyphylla tetraploids.
基金the National Natural Science Foundation of China(22203046 and 52102265)Jiangsu Provincial Natural Science Foundation(BK20230368 and BK20210604)+2 种基金the Project of State Key Laboratory of Organic Electronics and Information Displays,Nanjing University of Posts and Telecommunications(GZR2023010003,GZR2022010017 and GDX2022010010)the Natural Science Research Start-up Foundation of Recruiting Talents of Nanjing University of Posts and Telecommunications(NY221128,NY223099 and NY223054)the Natural Science Research Start-up Foundation of Recruiting Talents of Suzhou Vocational Institute of Industrial Technology(SYG202354)。
文摘The development of low-cost,high-performance catalysts at the atomic scale has become a challenging issue for the large-scale applications of renewable clean energy technologies.Herein,on the basis of density functional theory calculation,we systematically investigate the effect of the local environment on the activity and selectivity of electrochemical carbon dioxide reduction reaction over single/multi-atom alloy clusters formed by the transition metal(Fe,Co,and Ni)-doped Cu13/55 clusters.Our findings reveal that the catalytic performance of multi-atom alloy clusters far exceeds that of Cu(211)surface.Notably,the Co666 configuration exhibits exceptional performance with a remarkably low free energy barrier of just 0.33 eV.Furthermore,our investigations demonstrate that catalytic performance is predominantly determined by the relative proportion of modifying metallic dopant species that generate a coordination number of 6.This ratio principally influences the adsorption strength of key intermediates(HCOO*and H2COO*).Bader charge analyses and free energy calculations elucidate a new mechanistic pathway,wherein the hydrogenation of CO_(2)at C-sites catalyzes the reduction of CO_(2)to CH_(4).This theoretical research provides valuable insights into the fundamental processes and energy landscapes involved in converting CO_(2)to CH_(4)on the studied catalytic structure,potentially paving the way for more efficient and sustainable carbon dioxide utilization strategies.
文摘A combined treatment technology （DEF-BIO） using the direct electro-Fenton （DEF） process and bioremediation （BIO） was established in this study. The performance of the DEF-BIO process on the remediation of a pyrene （PYR）-contaminated soil was evaluated in a slurry reactor. The appropriate order of application was to conduct the DEF process followed by BIO, evaluated through analysis of the degradation characteristics of each process individually. In addition, the application time of the DEF process affected the efficiency of the combined process. The optimum time to apply the DEF process was determined through an analysis of the induced changes in PYR intermediates, pH, soil organic matter （SOM） and bacteria. The optimum application time of the DEF process was 6 h. All the induced changes were beneficial for the BIO phase. The removal of PYR was 91.02% for DEF- BIO after 72h, and the efficiency was almost 50% increased, compared with the individual DEF and BIO treatments. Therefore, the combined process of DEF-BIO process may be an efficient and promising method for the remediation.
