We conducted genome sequence analysis to examine the presence/absence of two types of Z-DNA binding domains in various organisms. We examined 68 organisms from archaea, 914 organisms from bacteria, and 199 organisms f...We conducted genome sequence analysis to examine the presence/absence of two types of Z-DNA binding domains in various organisms. We examined 68 organisms from archaea, 914 organisms from bacteria, and 199 organisms from eukaryotes. RecA protein from Escherichia coli has a Z-DNA binding domain and this protein promotes homologous recombination. All the organisms examined had this domain. This result indicated that this domain is essential for all the organisms. RNA editing enzyme, adenosine deaminase from human has another type of Z-DNA binding domain. This domain was observed in some organisms of archaea, bacteria, and eukaryotes. The presence/absence of Z-DNA binding domain in adenosine deaminase indicated that gain and loss of this domain had occurred in the process of evolution. The implication of presence and absence of this domain is discussed in this study.展开更多
In this paper,a discrete-time analysis of the third-order charge-pump based phase-locked loops (CPLLs) is presented in the presence of loop delay.The z-domain analysis of the closed-loop transfer function is derived a...In this paper,a discrete-time analysis of the third-order charge-pump based phase-locked loops (CPLLs) is presented in the presence of loop delay.The z-domain analysis of the closed-loop transfer function is derived and compared with the traditional s-domain method.The simulation results under SPECTRE show that,due to the sampling nature of CPLL,the traditional s-domain analysis is unable to predict its jitter peaking accurately,especially when the loop delay is taken into consideration.The impact of loop delay on the stability of the third-order CPLL system is further analyzed based on the proposed way.The stability limit of the wide bandwidth CPLL with loop delay is calculated.The circuit simulation results agree well with mathematical analysis.展开更多
The synthesis and properties of (Z)-1-(triphenylstannyl)-3-phenyl-1-buten-3-ol (1) are described. Compound 1 crystallizes from alcohol in the monoclinic space group P21/c with unit-cell dimensions a=9.296(2), 6=14.081...The synthesis and properties of (Z)-1-(triphenylstannyl)-3-phenyl-1-buten-3-ol (1) are described. Compound 1 crystallizes from alcohol in the monoclinic space group P21/c with unit-cell dimensions a=9.296(2), 6=14.081(3), c=18.390(5) A,B=97.70(2), V=2385.5(1) A3, Z=4, F(000)=1008, Dc=1.38 g.cm-3,u=10.88 cm-1, final R=0.0359 for 3079 observed reflection [I > 3(I)]. The X-ray diffraction analysis of this compound shows the presence of an intramolecular coordination to the tin atom giving rise to a five-membered ring in which the metal exhibits a distroted trignoal bipyramidal geometry; as a consequence, a phenyl group, probably the apical one, is cleaved more easily by bromine than the vinyl substituent.展开更多
文摘We conducted genome sequence analysis to examine the presence/absence of two types of Z-DNA binding domains in various organisms. We examined 68 organisms from archaea, 914 organisms from bacteria, and 199 organisms from eukaryotes. RecA protein from Escherichia coli has a Z-DNA binding domain and this protein promotes homologous recombination. All the organisms examined had this domain. This result indicated that this domain is essential for all the organisms. RNA editing enzyme, adenosine deaminase from human has another type of Z-DNA binding domain. This domain was observed in some organisms of archaea, bacteria, and eukaryotes. The presence/absence of Z-DNA binding domain in adenosine deaminase indicated that gain and loss of this domain had occurred in the process of evolution. The implication of presence and absence of this domain is discussed in this study.
基金Supported by National Natural Science Foundation of China(No.61204028)
文摘In this paper,a discrete-time analysis of the third-order charge-pump based phase-locked loops (CPLLs) is presented in the presence of loop delay.The z-domain analysis of the closed-loop transfer function is derived and compared with the traditional s-domain method.The simulation results under SPECTRE show that,due to the sampling nature of CPLL,the traditional s-domain analysis is unable to predict its jitter peaking accurately,especially when the loop delay is taken into consideration.The impact of loop delay on the stability of the third-order CPLL system is further analyzed based on the proposed way.The stability limit of the wide bandwidth CPLL with loop delay is calculated.The circuit simulation results agree well with mathematical analysis.
基金Project supported by the National Natural Sciences Foundation of China.
文摘The synthesis and properties of (Z)-1-(triphenylstannyl)-3-phenyl-1-buten-3-ol (1) are described. Compound 1 crystallizes from alcohol in the monoclinic space group P21/c with unit-cell dimensions a=9.296(2), 6=14.081(3), c=18.390(5) A,B=97.70(2), V=2385.5(1) A3, Z=4, F(000)=1008, Dc=1.38 g.cm-3,u=10.88 cm-1, final R=0.0359 for 3079 observed reflection [I > 3(I)]. The X-ray diffraction analysis of this compound shows the presence of an intramolecular coordination to the tin atom giving rise to a five-membered ring in which the metal exhibits a distroted trignoal bipyramidal geometry; as a consequence, a phenyl group, probably the apical one, is cleaved more easily by bromine than the vinyl substituent.