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文章利用光子转换理论给出了两种光纤的任意信道间隔、N信道单向受激拉曼散射（SRS）的稳态分析结果,提出了一种新型的具有平坦增益的宽带拉曼光纤放大器（FRA）。对64信道的波分复用（WDM）系统进行了仿真,为FRA增益平坦化提供了一种新的实现方法。

【Objective】MYB305 as a member of the MYB R2R3 subfamily, plays an important role in plant nectary development, nectar protein expression, starch accumulation and hydrolysis, and flavonoid synthesis. Therefore, it is of great significance to study the expression profile and function of MYB305 for the molecular mechanism study of Liriodendron tulipifera floral nectary.【Method】Having floral nectary of nectariferous plant L. tulipifera as materials, the anthocyanidin content in five stages of floral nectary was detected by spectrophotometry, LtMYB305 gene was cloned via RACE（rapid-amplification of cDNA ends）technology, and relative expressions among different tissues were analyzed by RT-qPCR assay. Then, subcellular localization of LtMYB305 protein was verified using tobacco leaves as materials, and the function of LtMYB305 gene was studied by genetic transformation approaches of wild type Arabidopsis thaliana（col）.【Result】The anthocyanidin in the nectaries of L. tulipifera was accumulated from the late expanding stage, increased sharply at the early flowering stage, and reached the highest of 27.14 μg/g at the withering stage, which was consistent with the process of nectar secretion and coloring. The full-length of LtMYB305 was 931 bp encoding 198 amino acids and its protein was hydrophilic and non-transmembrane. LtMYB305 was expressed highly only in the nectary of L. tulipifera at anthesis stage, and hardly in other tissues. LtMYB305 protein was localized in the nucleus. After the overexpression of LtMYB305, the nectary groove of the lateral nectary disappeared and deepened, the expressions of AtMYB30, AtPIN, AtSWEET9 genes related to flower nectary were up-regulated, and the expressions of AtCRC, AtBOP1/2, AtMYB21, AtSWEET3/4/7 genes were down-regulated.【Conclusion】 The LtMYB305 has typical characteristics of transcription factor and is involved to the nectary development in L. tulipifera. [ABSTRACT FROM AUTHOR]

CPP(Cystein-rich polycomb-like protein or Tesmin/TOS1-like)protein family are one kind of transcription factors with fewer members and possess a conserved, Cys-rich CRC domains. CPP transcription factor family plays an important role in the plant development of reproductive tissue and cell division. In this study, a CPP-like family gene was cloned by RACE methods from Liriodendron tulipifera named LtTCX2 to explore the function in regulating flower development. The full length of LtTCX2 was 2 866 bp. LtTCX2 contained an open reading frame(ORF)of 2 424 bp, encoding 807 amino acids with two conserved TSO1-like CXC domains by bioinformatics analysis on NCBI site. The molecular weight of protein was 88 699.25 Da, isoelectric point was 5.83 and coefficient of instability was 62.38. LtTCX2 was predicted to be hydrophilic and non-transmembrane nucleoprotein without signal peptide. The amino acid homology sequence and phylogenetic analysis demonstrated that LtTCX2 had high homology with other CPP-like family proteins and was most closely related with NnTCX2 in Nelumbo nucifera and PeTCX2 in Populus euphratica. Real-time quantitative PCR showed that LtTCX2 gene was highly expressed in the leaf and hardly expressed in the sepal and petal. The tissue specific expression order from high to low was that the leaf, flower bud, pistil, stamen, stem, root, petal and sepal. These results suggested that LtTCX2 is a rather conservative gene and provide several help to the phylogenetic evolution of Liriodendron plants from the molecular biology level. [ABSTRACT FROM AUTHOR]

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