三网融合的脚步越来越近,各地广电都在如火如荼的进行着双向网改造。VOD(Video On Demand)业务是变传统电视的被动收看模式为用户主动按兴趣点播习惯,体现三网融合优势的一个重要应用。如何在传统的有线电视网络快速、简单、稳定的部署...三网融合的脚步越来越近,各地广电都在如火如荼的进行着双向网改造。VOD(Video On Demand)业务是变传统电视的被动收看模式为用户主动按兴趣点播习惯,体现三网融合优势的一个重要应用。如何在传统的有线电视网络快速、简单、稳定的部署该项业务,同时充分利用现有设备,避免大规模的机房改造,保护已有投资,成为各地广电必须考虑的问题。2011年湘潭广电被选为湖南首批三网融合的试点城市,为此湘潭广电加快了网络改造的进度。本文通过对湘潭广电网络采用的VOD点播信号光插入技术进行介绍,意在为广大同仁介绍一种简单可行的VOD插入技术,以便快速的部署双向业务。展开更多
OBJECTIVE: To determine the karyotype of a cryptic structural abnormality and explore the mechanism of apparent chromosomal terminal deletion. METHODS: Fluorescence in situ hybridization(FISH) with a whole chromosome ...OBJECTIVE: To determine the karyotype of a cryptic structural abnormality and explore the mechanism of apparent chromosomal terminal deletion. METHODS: Fluorescence in situ hybridization(FISH) with a whole chromosome 7 painting probe and a 7q subterminal probe (7q36-->qter), prepared by chromosome microdissection technique, was used to analyze a case with a history of spontaneous abortion and 7q terminal deletion detected by conventional G-banding technique. RESULTS: The case was a maternal cryptic insertional translocation between chromosome region 1p32 and 7q32-->q35. The region of chromosome 7q36-->qter was not inserted in to chromosome 1, and the abnormal chromosome 7 was not a terminal deletion but an interstitial deletion. CONCLUSIONS: Chromosome insertion of the terminal region retains its telomere, which is consistent with the concept of a three-break rearrangement. Interstitial deletion may be regarded as another mechanism for terminal deletion in the chromosome banding level. Combined with chromosome microdissection, FISH technique could be a powerful diagnostic tool for detecting chromosome structural abnormalities.展开更多
An interrogation system based on two semiconductor optical amplifiers for weak fiber Bragg gratings （FBGs） was proposed. The first semiconductor optical amplifier （SOA） was used to modulate the light, and the seco...An interrogation system based on two semiconductor optical amplifiers for weak fiber Bragg gratings （FBGs） was proposed. The first semiconductor optical amplifier （SOA） was used to modulate the light, and the second SOA separated the reflected signal from the different FBGs through delayed switching. The proposed system has lower insertion loss and higher spatial resolution, and can interrogate the time- and wavelength-division multiplexed FBG array. Up to 50 FBGs, with a reflectivity of 0.2% and a spatial resolution of 5 m along the optical fiber, were distinguished to demonstrate the interrogation system.展开更多
文摘三网融合的脚步越来越近,各地广电都在如火如荼的进行着双向网改造。VOD(Video On Demand)业务是变传统电视的被动收看模式为用户主动按兴趣点播习惯,体现三网融合优势的一个重要应用。如何在传统的有线电视网络快速、简单、稳定的部署该项业务,同时充分利用现有设备,避免大规模的机房改造,保护已有投资,成为各地广电必须考虑的问题。2011年湘潭广电被选为湖南首批三网融合的试点城市,为此湘潭广电加快了网络改造的进度。本文通过对湘潭广电网络采用的VOD点播信号光插入技术进行介绍,意在为广大同仁介绍一种简单可行的VOD插入技术,以便快速的部署双向业务。
文摘OBJECTIVE: To determine the karyotype of a cryptic structural abnormality and explore the mechanism of apparent chromosomal terminal deletion. METHODS: Fluorescence in situ hybridization(FISH) with a whole chromosome 7 painting probe and a 7q subterminal probe (7q36-->qter), prepared by chromosome microdissection technique, was used to analyze a case with a history of spontaneous abortion and 7q terminal deletion detected by conventional G-banding technique. RESULTS: The case was a maternal cryptic insertional translocation between chromosome region 1p32 and 7q32-->q35. The region of chromosome 7q36-->qter was not inserted in to chromosome 1, and the abnormal chromosome 7 was not a terminal deletion but an interstitial deletion. CONCLUSIONS: Chromosome insertion of the terminal region retains its telomere, which is consistent with the concept of a three-break rearrangement. Interstitial deletion may be regarded as another mechanism for terminal deletion in the chromosome banding level. Combined with chromosome microdissection, FISH technique could be a powerful diagnostic tool for detecting chromosome structural abnormalities.
基金This work was supported in part by the National Science Foundation of China, NSFC （Gram No. 61205070）, and the Major Program of the National Natural Science Foundation of China, NSFC （Grant No. 61290311）.
文摘An interrogation system based on two semiconductor optical amplifiers for weak fiber Bragg gratings （FBGs） was proposed. The first semiconductor optical amplifier （SOA） was used to modulate the light, and the second SOA separated the reflected signal from the different FBGs through delayed switching. The proposed system has lower insertion loss and higher spatial resolution, and can interrogate the time- and wavelength-division multiplexed FBG array. Up to 50 FBGs, with a reflectivity of 0.2% and a spatial resolution of 5 m along the optical fiber, were distinguished to demonstrate the interrogation system.
