A new configuration for delay cells used in voltage controlled oscillators is presented. A jitter comparison between the source-coupled differential delay cell and the proposed CMOS inverter based delay cell is given....A new configuration for delay cells used in voltage controlled oscillators is presented. A jitter comparison between the source-coupled differential delay cell and the proposed CMOS inverter based delay cell is given. A new method to optimize loop parameters based on low-jitter in PLL is also introduced. A low-jitter 1.25GHz Serdes is implemented in a 0.35μm standard 2P3M CMOS process. The result shows that the RJ （random jitter） RMS of 1.25GHz data rate series output is 2. 3ps （0. 0015UI） and RJ （1 sigma） is 0. 0035UI. A phase noise measurement shows - 120dBc/Hz@100kHz at 1111100000 clock-pattern data out.展开更多
MicroRNAs （miRNAs） are important post-transcriptional regulators of their target genes in plants and animals, miRNAs are usually 20-24 nucleotides long. Despite their unusually small sizes, the evolutionary history ...MicroRNAs （miRNAs） are important post-transcriptional regulators of their target genes in plants and animals, miRNAs are usually 20-24 nucleotides long. Despite their unusually small sizes, the evolutionary history of miRNA gene families seems to be similar to their protein-codingcounterparts. In contrast to the small but abundant miRNA families in the animal genomes, plants have fewer but larger miRNA gene families. Members of plant miRNA gene families are often highly similar, suggesting recent expansion via tandem gene duplication and segmental duplication events. Although many miRNA genes are conserved across plant species, the same gene family varies significantly in size and genomic organization in different species, which may cause dosage effects and spatial and temporal differences in target gene regulations. In this review, we summarize the current progress in understanding the evolution of plant miRNA gene families.展开更多
文摘A new configuration for delay cells used in voltage controlled oscillators is presented. A jitter comparison between the source-coupled differential delay cell and the proposed CMOS inverter based delay cell is given. A new method to optimize loop parameters based on low-jitter in PLL is also introduced. A low-jitter 1.25GHz Serdes is implemented in a 0.35μm standard 2P3M CMOS process. The result shows that the RJ （random jitter） RMS of 1.25GHz data rate series output is 2. 3ps （0. 0015UI） and RJ （1 sigma） is 0. 0035UI. A phase noise measurement shows - 120dBc/Hz@100kHz at 1111100000 clock-pattern data out.
文摘MicroRNAs （miRNAs） are important post-transcriptional regulators of their target genes in plants and animals, miRNAs are usually 20-24 nucleotides long. Despite their unusually small sizes, the evolutionary history of miRNA gene families seems to be similar to their protein-codingcounterparts. In contrast to the small but abundant miRNA families in the animal genomes, plants have fewer but larger miRNA gene families. Members of plant miRNA gene families are often highly similar, suggesting recent expansion via tandem gene duplication and segmental duplication events. Although many miRNA genes are conserved across plant species, the same gene family varies significantly in size and genomic organization in different species, which may cause dosage effects and spatial and temporal differences in target gene regulations. In this review, we summarize the current progress in understanding the evolution of plant miRNA gene families.
