发夹式DNA探针检测水中汞EI北大核心CSCD

利用荧光染料双标记的DNA探针,实现了对水中Hg^(2+)的一步检测。实验中使用的DNA探针是富T结构的发夹式DNA探针链,若水样中不存在Hg^(2+),双标记的DNA探针两端的荧光染料Cy3与Cy5之间的距离很小,会发生荧光能量共振转移,Cy3的荧光发射强度降低;反之,Hg^(2+)会与DNA探针上的T碱基生成T-Hg^(2+)-T的稳定结构,使DNA链结构发生变化,同时Cy3,Cy5之间的距离变大,二者间的能量共振转移减弱甚至消失,Cy3的荧光发射强度回升。因此,通过Hg^(2+)的浓度与Cy3的荧光发射强度的变化的线性关系,可以实现Hg^(2+)的定量检测。     

多卤代吡咯类化合物的电子轰击质谱

近几年来的研究成果表明,某些含卤素的吡咯化合物,具有明显的生理活性和药物性能,其中不少是从海洋生物中分离出来的天然化合物,对于这些天然活性分子及其系列类似物的合成方法,已有许多研究,但对这类化合物的质     

2010年立体几何考点解读与命题规律探究

1．考点一：空间几何体的结构、三视图、直观图 考点解读：了解柱、锥、台、球体及其简单组合体的结构特征,并能运用这些特征描述现实生活中的简单物体的结构．能画出简单空间几何体的三视图,能识别上述三视图所表示的立体模型,会用斜二测画法画出它们的直观图．能用平行投影与中心投影两种方法画出简单空间几何体的三视图与直观图．了解空间几何体的不同表示形式．会画某建筑物的视图与直观图．     

个离散造血模型概周期解的吸引性和振动性(英文)

By using a new fixed point theorem, sufficientconditions are obtained for the existence of a positivealmost-periodic solution for an discrete model of hematopoiesis with almost-periodic coefficients. Its attractivity and oscillation are investigated.     

Time-Dependent Variational Approach to Ground-State Phase Transition and Phonon Dispersion Relation of the Quantum Double-Well Model

The ground-state phase transition and the phonon dispersion relation of the quantum double-well model are studied by means of the time-dependent variational approach combined with a Hartree-type many-body trial wavefunction. The single-particle state is taken to be a frozen Jackiw-Kerman wavefunction. Under the condition of minimum uncertainty relation, we obtain an effective classical Hamiltonian for the system and equations of motion for the particle＇s expectation values. It is shown that the effective substrate potential transits from a symmetric double-well potential to a symmetric single-well potential, and the ground state exhibits a transition from a broken symmetry phase to a restored symmetry phase as increasing the strength of quantum fluctuations. We also obtain the phonon dispersion relations and the phonon gaps at the two phases.     

斑马鱼TDP43负调控Ⅰ型干扰素的表达

TDP43是一种DNA/RNA结合蛋白,属于异质核糖核蛋白家族成员,在调控转录、mRNA稳定性及翻译等方面发挥重要作用。近年来有报道表明哺乳类TDP43参与了炎症和免疫反应,然而TDP43在免疫应答中的功能机制还不清楚。探索了斑马鱼TDP43在先天免疫反应中的功能。首先通过同源比对及构建TDP43的系统进化树,分析了TDP43在不同物种中的进化特征,结果表明TDP43在哺乳类和鱼类中的相似度很高(60%以上)。SVCV病毒感染斑马鱼和CIK细胞后,检测TDP43在各组织和细胞中表达发现,(脑、眼睛、肠、鳃、皮肤、心脏、肝脏和肾脏)和CIK细胞中均上调。体外构建TDP43真核表达载体或合成TDP43的小干扰RNA,在CIK细胞中过表达TDP43能够抑制了Ⅰ型干扰素表达,而敲降TDP43则上调了Ⅰ型干扰素的表达。此外,亚细胞定位分析表明TDP43主要定位于细胞核,说明TDP43可能是在细胞核中调控基因的转录而控制先天免疫反应。总之,我们研究了斑马鱼TDP43在响应病毒感染及在先天免疫反应中的功能。     

Efficient scheme of quantum SWAP gate and multi-atom cluster state via cavity QED

In this paper, we propose a physical scheme to realize quantum SWAP gate by using a large-detuned single-mode cavity field and two identical Rydberg atoms. It is shown that the scheme can also be used to create multi-atom cluster state. During the interaction between atom and cavity, the cavity is only virtually excited and thus the scheme is insensitive to the cavity field states and cavity decay. With the help of our scheme it is very simple to prepare the N-atom cluster state with perfect fidelity and probability. The practical feasibility of this method is also discussed.     

二项式光场与级联三能级原子的量子纠缠

利用量子熵理论，研究了二项式光场与级联三能级原子的量子纠缠，讨论了光场与原子的初始参量对其量子纠缠性质的影响.结果表明，利用二项式光场的特性，可以揭示从相干态到数态之间的所有态光场与三能级原子相互作用时的量子纠缠性质.选择适当的系统参数可以制备稳定的光场-原子qutrit纠缠态. 关键词： 二项式光场 级联三能级原子 光场熵 量子纠缠     

Stark位移对热环境下双Jaynes-Cummings模型中原子纠缠的影响

研究双光子跃迁的双Jaynes-Cummings模型中, 两原子初始处于最大纠缠态、光场初始处于单模热态时的原子纠缠动力学, 考虑双光子过程中的Stark位移、热光场的平均光子数对原子纠缠的影响. 结果表明: 不考虑Stark位移时, 两原子在系统演化过程中周期性地出现退纠缠现象, 而考虑Stark位移时, 两原子长时间地纠缠. 特别是当Stark位移参数取值较大且热光场的平均光子数值比较小时, 两原子能保持 稳定地纠缠. 这些结果表明, 可以利用Stark位移对热环境下双Jaynes-Cummings模型中的原子纠缠进行调控.     

Quantum entanglement in the mode-mode competition system

Considering a two-level atom interacting with the competing two-mode field, this paper investigates the entanglement between the two-level atom and the two-mode field by using the quantum reduced entropy, and that between the two-mode field by using the quantum relative entropy of entanglement. It shows that the two kinds of entanglement are dependent on the relative coupling strength of atom-field and the atomic distribution, and exhibit the periodical evolution. The maximal atom-field entanglement state can be prepared via the appropriate selection of system parameters and interaction time.