The general analytic expression of the chirped sampled function is derived based on coupled mode theory. This function can be used to describe how to use uniform period fiber Bragg grating to produce the equal chirp a...The general analytic expression of the chirped sampled function is derived based on coupled mode theory. This function can be used to describe how to use uniform period fiber Bragg grating to produce the equal chirp at will in the specific reflection channel. As an example,the exact sampled function expression that produces a linear chirped at the +4 channel is given. The simulation results by using the transfer-matrix show that the theory is correct.展开更多
Mammalian testis development is a complex and highly sophisticated process. To study the dynamic change of normal testis development at the transcriptional level, we investigated mouse testes at three postnatal ages: ...Mammalian testis development is a complex and highly sophisticated process. To study the dynamic change of normal testis development at the transcriptional level, we investigated mouse testes at three postnatal ages: 6 days postnatal, 4 weeks old, and 10 weeks old, representing infant (PN1), juvenile (PN2), and adult (PN3) stages, respectively. Using ultra high-throughput RNA sequencing (RNA-seq) technology, we obtained 211 million reads with a length of 35 bp. We identified 18837 genes that were expressed in mouse testes, and found that genes expressed at the highest level were involved in spermatogenesis. The gene expression pattern in PN1 was distinct from that in PN2 and PN3, which indicates that spermatogenesis has commenced in PN2. We analyzed a large number of genes related to spermatogenesis and somatic development of the testis, which play important roles at different developmental stages. We also found that the MAPK, Hedgehog, and Wnt signaling pathways were significantly involved at different developmental stages. These findings further our understanding of the molecular mechanisms that regulate testis development. Our study also demonstrates significant advantages of RNA-seq technology for studying transcriptome during development.展开更多
基金Supported National "863" High Technology Project of China(No.2003AA311070) andthe National Natural Science Founda-tion of China (No.60377026 ) .
文摘The general analytic expression of the chirped sampled function is derived based on coupled mode theory. This function can be used to describe how to use uniform period fiber Bragg grating to produce the equal chirp at will in the specific reflection channel. As an example,the exact sampled function expression that produces a linear chirped at the +4 channel is given. The simulation results by using the transfer-matrix show that the theory is correct.
基金supported by the National Basic Research Program of China(2011CB944100,2011CB944101)the National Natural Science Foundation of China (90919024)+1 种基金the Special Foundation Work Program of Ministry of Science and Technology (2009FY120100)the National High Technology Research and Development Program of Ministry of Science and Technology of China (2012AA020409)
文摘Mammalian testis development is a complex and highly sophisticated process. To study the dynamic change of normal testis development at the transcriptional level, we investigated mouse testes at three postnatal ages: 6 days postnatal, 4 weeks old, and 10 weeks old, representing infant (PN1), juvenile (PN2), and adult (PN3) stages, respectively. Using ultra high-throughput RNA sequencing (RNA-seq) technology, we obtained 211 million reads with a length of 35 bp. We identified 18837 genes that were expressed in mouse testes, and found that genes expressed at the highest level were involved in spermatogenesis. The gene expression pattern in PN1 was distinct from that in PN2 and PN3, which indicates that spermatogenesis has commenced in PN2. We analyzed a large number of genes related to spermatogenesis and somatic development of the testis, which play important roles at different developmental stages. We also found that the MAPK, Hedgehog, and Wnt signaling pathways were significantly involved at different developmental stages. These findings further our understanding of the molecular mechanisms that regulate testis development. Our study also demonstrates significant advantages of RNA-seq technology for studying transcriptome during development.