基于纳米结构材料的磷酸化蛋白/多肽富集和分析

蛋白质磷酸化是最为广泛的翻译后修饰之一。在生物体液或组织中,许多低丰度的磷酸化蛋白和磷酸化肽是具有高度临床灵敏性和特异性的生物标记物,这些生物分子对许多疾病的检测和病理的阐释可能提供重要的信息。因为蛋白质磷酸化动态可逆且磷酸化蛋白丰度很低,所以很难直接从复杂的生物样品中直接检测到磷酸化蛋白和磷酸化肽。纳米结构材料因其大比表面积、丰富的活性亲合位点和特殊结构,在磷酸化肽和磷酸化蛋白的分离和富集方面已经引起了特别的关注,并成为目前磷酸化蛋白质组学富集和鉴定方面的研究热点。许多介孔、磁性、杂化或化学修饰的亲合材料被研发并用于磷酸化蛋白/多肽的富集与分离;此外,一些多功能纳米结构材料也被研发并用于蛋白质组学中磷酸化蛋白/多肽的快速高效的富集提纯。在这篇综述中,我们专注于纳米结构材料在磷酸化蛋白/多肽富集和提纯方面的最新进展。     

A new polymorph of bis(2‐aminopyridinium) fumarate–fumaric acid (1/1) from powder X‐ray diffraction

A new polymorph of bis(2‐aminopyridinium) fumarate–fumaric acid (1/1), 2C₅H₇N₂⁺·C₄H₂O₄²⁻·C₄H₄O₄, was obtained and its crystal structure determined by powder X‐ray diffraction. The new polymorph (form II) crystallizes in the triclinic system (space group P), while the previous reported polymorph [form I; Ballabh, Trivedi, Dastidar & Suresh (2002). CrystEngComm, 4 , 135–142; Büyükgüngör, Odabaşoğlu, Albayrak & Lönnecke (2004). Acta Cryst. C 60 , o470–o472] is monoclinic (space group P2₁/c). In both forms I and II, the asymmetric unit consists of one 2‐aminopyridinium cation, half a fumaric acid molecule and half a fumarate dianion. The fumarate dianion is involved in hydrogen bonding with two neighbouring 2‐aminopyridinium cations to form a hydrogen‐bonded trimer in both forms. In form II, the hydrogen‐bonded trimers are interlinked across centres of inversion via pairs of N—H...O hydrogen bonds, whereas such trimers are joined via single N—H...O hydrogen bonds in form I, leading to different packing modes for forms I and II. The results demonstrate the relevance and application of the powder diffraction method in the study of polymorphism of organic molecular materials.     

Passively mode-locked fiber laser with kilohertz magnitude repetition rate and tunable pulse width

We propose and demonstrate a strictly all-fiber, erbium doped passively mode-locked figure-eight fiber laser (EDFL). In the laser structure, we use the nonlinear optical loop mirror combination with a variable ratio coupler (VRC-NOLM) to achieve mode-locking. Due to the nonlinear effect in the nonlinear fiber, stable self-starting pulse is obtained. In order to reduce the repetition of pulse, a segment of nonlinear fiber (NLF) has been incorporated into the VRC-NOLM. The laser generates stable rectangular pulses with a low repetition rate (kilohertz magnitude) by extending the length of the cavity. Furthermore, the output pulse width of the fiber laser can be varied by changing the coupler ratio of the variable ratio coupler.     

Large aperture tapered fiber phase conjugate mirror in MOPA laser systems with high repetition rate and high pulse energy

A large aperture tapered fused silica fiber phase conjugate mirror with a maximum 50.7% stimulated Brillouin scattering (SBS) reflectivity is presented, which is operated with 400 Hz pulse repetition rate and 36.5 mJ input pulse energy. To the best of our knowledge, it is the first time that over 50% SBS reflectivity is achieved by using solid-state phase conjugate mirror under such high pulse repetition rate and high pulse energy. With much higher pulse repetition rate of 500 and 1000 Hz, the maximum SBS reflectivity is 41.2% and 33.3%, respectively. A single-longitudinal-mode Nd:YAG laser is experimentally studied with master oscillator power amplifier (MOPA) scheme using such a tapered fiber as a phase conjugate mirror. A 101 mJ pulse energy is achieved at 400 Hz repetition rate, with a pulse width of 6 ns and a M² factor of less than 2. The corresponding peak power reaches 16.8 MW.     

超越整函数Fatou分支的某些性质

讨论了有限个超越整函数fi(i=1,2,…,m}迭代生成的函数g=f1 o f2 o…o fm 的Fatou分支的性质,给出了g(z)的Fatou分支有界的一个充分条件.并证明了在该条件下,对g的任意游荡域U,都有{gn}的一个子列在U上趋于∞.     

微波辐射下吲哚连噁二唑啉衍生物的合成和抗菌活性测定

把噁二唑结构引入吲哚环中,合成一类结构新颖的吲哚衍生物,以期为新药筛选提供先导化合物.在微波辐射条件下,以较高的产率得到9个未见文献报道的新化合物,其结构均经1HNMR,IR,MS及元素分析所证实,并测试了化合物的抑菌活性.     

Iron‐mediated AGET ATRP of methyl methacrylate in the presence of polar solvents as ligands

The polar solvents, N‐methylpyrrolidone (NMP), N,N‐dimethylformamide (DMF), and acetonitrile (CH₃CN) were used as ligands for iron(III)‐mediated activators generated by electron transfer atom transfer radical polymerizations (AGET ATRPs) of methyl methacrylate (MMA) with various initiators and reducing agents. Polymerizations were conducted with a molar ratio of [MMA]₀/[initiator]₀/[FeBr₃]₀/[reducing agent]₀ = 100:1:1:0.5 and a volume ratio of MMA/solvent = 2:1 at 60 °C to investigate the effects of initiator, solvent and reducing agent, and most of the systems showed the typical features of “living”/controlled radical polymerization. In order to get a deeper understanding of the mechanism, the amount of the reducing agent was changed to study the polymerization behavior. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 1020–1027     

Syntheses,Crystal Structures and Luminescent Properties of a Dimeric Complex [(bzdmpzm)Cu(μ-I)]2 and a Polymeric Complex [(bzdmpzm)Cu(μ-NCS)]n (bzdmpzm=Bis(4-benzyl-3,5-dimethyl-1H-pyrazol-1-yl)methane)

Reactions of CuX (X=I, NCS) with bis(4‐benzyl‐3,5‐dimethyl‐1H‐pyrazol‐1‐yl)methane (bzdmpzm) in MeCN resulted in the formation of one dimer [(bzdmpzm)Cu(µ‐I)]₂ ( 1 ) and one 1D polymer [(bzdmpzm)Cu(µ‐NCS)]_n ( 2 ) in high yields. 1 and 2 were characterized by elemental analysis, IR, ¹H NMR spectra, powder X‐ray diffraction and single‐crystal X‐ray diffraction. 1 consists of two scorpion‐like [(bzdmpzm)Cu]⁺ fragments bridged by two iodides, forming a dimeric structure. 2 contains a unique 1D scolopendra‐like chain of [(bzdmpzm)Cu]⁺ fragments linked by pairs of thiocyanates. The luminescence properties of 1 and 2 were also investigated.     

重离子碰撞中同位旋自由度输运和对称能约束

重离子核反应是地面实验室研究核物质状态方程的有效手段。当核物质体系 (包括原子核) 中的中子和质子数目差异很大时，核物质状态方程中除了对称核物质贡献之外，对称能项的贡献逐渐变得重要。它反映了核子相互作用势的同位旋矢量部分，与致密星体的性质和恒星核合成等天体物理基本问题，以及远离β稳定线原子核的奇异性质与核素图边界等核物理前沿问题，都紧密相关。然而，迄今为止，对称能对密度的依赖行为尚未很精确地约束。因此，对称能的研究成为当前国际上主要的中能核物理实验室和天体观测装置的主要物理目标之一。本文简单评述了这一领域的实验进展，并介绍了基于国内的大科学装置，即兰州重离子研究装置(HIRFL)开展费米能区重离子反应与对称能实验研究的一些进展。实验结果表明，这一能区的同位旋自由度输运时标和具体的物理过程相关，同位旋漂移效应可能持续到反应晚期。由于同位旋效应的长时间积累，轻粒子同位旋的角度分布可以用来约束对称能的密度依赖，在饱和点附近对称能值为$ S\!=\!28.3 $ MeV的条件下，其斜率参数约束在$L\!=\!33\!\sim\! 61\,\mathrm{M}\mathrm{e}\mathrm{V}$的区间，置信度水平为95%。借助一套具有裂变碎片和带电粒子符合测量能力的高性能重离子反应测量谱仪，可以测量具有同位素分辨的带电粒子小角关联函数，从而给出费米能区重离子反应中同位旋驰豫的时标。最后，介绍了氘核的同位旋矢量极化效应，该效应可能提供一种全新的约束对称能密度依赖的途径。     

基于龙格-库塔方法的-阶微分方程组的初值问题

本文在Runge-Kutta方法的基础上，讨论了一阶微分方程组当其初始状态具有模糊不确定性时，运用模糊仿真的近似推理规则，求其数值解的方法．