Single-cell RNA sequencing(scRNA-seq)is generally used for profiling transcriptome of individual cells.The droplet-based 10X Genomics Chromium(10X)approach and the plate-based Smart-seq2 full-length method are two fre...Single-cell RNA sequencing(scRNA-seq)is generally used for profiling transcriptome of individual cells.The droplet-based 10X Genomics Chromium(10X)approach and the plate-based Smart-seq2 full-length method are two frequently used scRNA-seq platforms,yet there are only a few thorough and systematic comparisons of their advantages and limitations.Here,by directly comparing the scRNA-seq data generated by these two platforms from the same samples of CD45cells,we systematically evaluated their features using a wide spectrum of analyses.Smart-seq2 detected more genes in a cell,especially low abundance transcripts as well as alternatively spliced transcripts,but captured higher proportion of mitochondrial genes.The composite of Smart-seq2 data also resembled bulk RNA-seq data more.For 10X-based data,we observed higher noise for mRNAs with low expression levels.Approximately 10%30%of all detected transcripts by both platforms were from non-coding genes,with long non-coding RNAs(lncRNAs)accounting for a higher proportion in 10X.10X-based data displayed more severe dropout problem,especially for genes with lower expression levels.However,10X-data can detect rare cell types given its ability to cover a large number of cells.In addition,each platform detected distinct groups of differentially expressed genes between cell clusters,indicating the different characteristics of these technologies.Our study promotes better understanding of these two platforms and offers the basis for an informed choice of these widely used technologies.展开更多
The calcium chloride used for adsorption separation of ammonia is promising for its large adsorptive capacity and lower desorption temperature,but difficult to develop because of the liable expansion,lump and chip in ...The calcium chloride used for adsorption separation of ammonia is promising for its large adsorptive capacity and lower desorption temperature,but difficult to develop because of the liable expansion,lump and chip in the adsorption/desorption process.Composite adsorbents made by monolayer dis-persion of calcium chloride onto carriers with high surface areas exhibit better adsorptive capacity and stability.Several models were developed to confirm the maximum monolayer dispersion capacity of calcium chloride onto the carriers(the distribution threshold value),and the closely packed monolayer dispersion model was considered the most suitable for this study.The distribution threshold values given by this model were 0.60 g CaCl2/(g 10X-zeolite) and 0.38 g CaCl2/(g SiO2).When the divalent salt was dispersed onto the carriers,however,anions were separated into two types,causing that the en-tropy of the system tended to increase and the system was not stable.To minimize the entropy,a new model was put forward as the modified closely packed monolayer dispersion model.Based on this model,the distribution threshold values are 0.52 g CaCl2/(g 10X-zeolite) and 0.33 g CaCl2/(g SiO2),re-spectively.The distribution threshold values were also gained experimentally by XRD quantitative phase analysis:0.61 g CaCl2/(g 10X-zeolite) and 0.31 g CaCl2/(g SiO2).Comparison between experi-mental values of distribution threshold with theoretical ones based on two different model showed that the closely packed monolayer dispersion model fits the monolayer dispersion of calcium chloride onto micro-pore carrier - 10X-zeolite,and the modified closely packed monolayer dispersion model is more suitable for the bigger aperture carrier - macro-pore silica gel.展开更多
基金the National Natural Science Foundation of China(Grant Nos.31530036,81573022,and 31601063).
文摘Single-cell RNA sequencing(scRNA-seq)is generally used for profiling transcriptome of individual cells.The droplet-based 10X Genomics Chromium(10X)approach and the plate-based Smart-seq2 full-length method are two frequently used scRNA-seq platforms,yet there are only a few thorough and systematic comparisons of their advantages and limitations.Here,by directly comparing the scRNA-seq data generated by these two platforms from the same samples of CD45cells,we systematically evaluated their features using a wide spectrum of analyses.Smart-seq2 detected more genes in a cell,especially low abundance transcripts as well as alternatively spliced transcripts,but captured higher proportion of mitochondrial genes.The composite of Smart-seq2 data also resembled bulk RNA-seq data more.For 10X-based data,we observed higher noise for mRNAs with low expression levels.Approximately 10%30%of all detected transcripts by both platforms were from non-coding genes,with long non-coding RNAs(lncRNAs)accounting for a higher proportion in 10X.10X-based data displayed more severe dropout problem,especially for genes with lower expression levels.However,10X-data can detect rare cell types given its ability to cover a large number of cells.In addition,each platform detected distinct groups of differentially expressed genes between cell clusters,indicating the different characteristics of these technologies.Our study promotes better understanding of these two platforms and offers the basis for an informed choice of these widely used technologies.
基金Supported by the National Natural Science Foundation of China (Grant No. 20576080)
文摘The calcium chloride used for adsorption separation of ammonia is promising for its large adsorptive capacity and lower desorption temperature,but difficult to develop because of the liable expansion,lump and chip in the adsorption/desorption process.Composite adsorbents made by monolayer dis-persion of calcium chloride onto carriers with high surface areas exhibit better adsorptive capacity and stability.Several models were developed to confirm the maximum monolayer dispersion capacity of calcium chloride onto the carriers(the distribution threshold value),and the closely packed monolayer dispersion model was considered the most suitable for this study.The distribution threshold values given by this model were 0.60 g CaCl2/(g 10X-zeolite) and 0.38 g CaCl2/(g SiO2).When the divalent salt was dispersed onto the carriers,however,anions were separated into two types,causing that the en-tropy of the system tended to increase and the system was not stable.To minimize the entropy,a new model was put forward as the modified closely packed monolayer dispersion model.Based on this model,the distribution threshold values are 0.52 g CaCl2/(g 10X-zeolite) and 0.33 g CaCl2/(g SiO2),re-spectively.The distribution threshold values were also gained experimentally by XRD quantitative phase analysis:0.61 g CaCl2/(g 10X-zeolite) and 0.31 g CaCl2/(g SiO2).Comparison between experi-mental values of distribution threshold with theoretical ones based on two different model showed that the closely packed monolayer dispersion model fits the monolayer dispersion of calcium chloride onto micro-pore carrier - 10X-zeolite,and the modified closely packed monolayer dispersion model is more suitable for the bigger aperture carrier - macro-pore silica gel.