Real-time non-destructive testing of dynamic holograms in doubly-doped LiNbO3 crystals using phase-conjugate technique

Nankai University

Highly enantioselective conjugate addition of diethylzinc to acyclic enones with fine-tunable phosphite-pyridine ligands

A new series of fine-tunable phosphite-pyridine (P,N) ligands derived from (S)-2-amino-T-hydroxy-6,6'-dimethyl-1,1'-biphenyl and (S)-2-amino-2'-hydroxy-4,4',6,6'-tetramethyl-1,1'-biphenyl was employed in Cu(I)-catalyzed conjugate addition of diethylzinc to acyclic enones. Excellent enantioselectivities (up to 98% ee) and highly catalytic activities were achieved for a variety of acyclic enones.

Biodegradable amphiphilic polymer-drug conjugate micelles

The coupling of drugs to macromolecular carriers received an important impetus from Ringsdorf's notion of polymer-drug conjugates. Several water-soluble polymers, poly(ethylene glycol), poly[N-(2-hydroxypropyl) methacrylamidel, poly(L-glutamic acid) and dextran, are studied intensively and have been utilized successfully in clinical research. The promising results arising from clinical trials with polymer-drug conjugates (e.g., paclitaxel, doxorubicin, camptothecins) have provided a firm foundation for other synthetic polymers, especially biodegradable polymers, used as drug delivery vehicles. This review discusses biodegradable polymeric micelles as an alternative drug-conjugate system. Particular focus is on A-B or B-A-B type biodegradable amphiphilic block copolymer such as polylactide, morpholine-2,5-dione derivatives and cyclic carbonates, which can form a core-shell micellar structure, with the hydrophobic drug-binding segment forming the hydrophobic core and the hydrophilic segment as a hydrated outer shell. Polymeric micelles can be designed to avoid uptake by cells of reticuloendothelial system and thus enhance their blood lifetime via the enhanced permeability and retention effect.

Synthesis and characterization of the paclitaxel/MPEG-PLA block copolymer conjugate

A paclitaxel/MPEG-PLA block copolymer conjugate was prepared in three steps: (1) hydroxyl-terminated diblock copolymer of monomethoxy-poly(ethylene glycol)-b-poly(lactide) (MPEG-PLA) was synthesized by ring-opening polymerization of L-lactide using MPEG as a maroinitiator, (2) it was converted to carboxyl-terminated MPEG-PLA by reacting with mono-i-butyl ester of diglycolic acid and subsequent deprotecting the t-butyl group with TFA; (3) the latter was reacted with paclitaxel in the presence of dicyclohexylcarbodiimide and dimethylaminopyridine. Structures of the polymers synthesized were confirmed by H-1 NMR, and their molecular weights were determined by gel permeation chromatography. The antitumor activity of the conjugate against human liver cancer H7402 cells was evaluated by MTT method. The results showed that paclitaxel can be released from the conjugate without losing cytotoxicity.

一种新型阻性板室（RPC）探测器的研制

气体探测器在核物理及粒子物理领域有着广泛的应用，尤其是阻性板室探测器，以其低廉的造价、优异的性能在各个大型实验室中都发挥着重要的作用。日本国家高能物理实验室(KEK)的Belle探测器，斯坦福大学斯坦福直线加速器中心(SLAC)的BaBar大型探测器，欧洲核子中心(CERN)的大型强子对撞机(LHC)的CMS与ATLAS谱仪，北京高能物理研究所(IHEP)的BESⅢ谱仪都使用阻性板室作为触发系统或缪子探测器。 随着HIRFL-CSR项目的完工。RIBLL2开展高能放射性束物理实验成为可能，而为了鉴别高能重离子碰撞实验中出射的高能轻粒子，有必要测量粒子的飞行时间(TOF)。为此，我们研制了单隙定时RPC，并作了简单性能测试。在CSR实验终端上，它可以作为传统塑料闪烁晶体+PMT时间探测器的替代，成为反应出射产物测量的大型探测器系统(4π)中的重要成员。 本论文对RPC的发展历史以及被广泛应用的原因做了深入而详细的研究，并对RPC的结构、性能、工作模式、特点、气体系统等进行了深入探讨。研制了一套单气隙RPC探测器样机，测设了一些相关性能，并对所遇到问题的产生原因以及解决方案进行了分析。为了测试RPC的需要，搭建了一套多组分工作气体配气系统，论文中还对包括质量流量计的选定，相关配件的选择，以及后期整个配气系统的组装与调试进行了详细描述

Spectroscopic properties of the C-phycocyanin-allophycocyanin conjugate and the isolated phycobilisomes from Spirulina platensis

C-phycocyanin (CPC) and allophycocyanin (APC) were purified from Spirulina platensis, then the CPC was attached covalently to the APC by reacting their epsilon-amino groups. The excitation energy could be transferred from the CPC to the APC in the CPC-APC conjugate. Intact phycobilisomes (PBS), consisting of CPC, APC, colourless linker polypeptides, and APC B or L-cm, were isolated from S. platensis. Spectroscopic properties of the isolated PBSs kept at 20 degrees C for various times showed that the connection between the APC and the APC B or L-cm was looser than that between the CPC and the APC in the isolated PBSs. The CPC-APC conjugate was more stable than the isolated PBSs, and the linker polypeptides had a minor influence on the excitation energy transfer characteristic between different phycobiliproteins in the PBS.

Bacteremic pneumonia before and after withdrawal of 13-valent pneumococcal conjugate vaccine from a public vaccination program in Spain: a case-control study

The objective of this study is to compare the incidence and epidemiology of bacteremic community-acquired pneumonia (CAP) in the setting of changes in 13-valent pneumococcal conjugate vaccine (PCV13) coverage. In the region of Madrid, universal immunization with the PCV13 started in May 2010. In July 2012, public funding ceased. Vaccination coverage decreased from >95% to 82% in 2013 and to 67% in 2014. We performed a multicenter surveillance and case-control study from 2009-2014. Cases were hospitalized children with bacteremic CAP. Controls were children selected 1:1 from next-admitted with negative blood cultures and typical, presumed bacterial CAP. Annual incidence of bacteremic CAP declined from 7.9/100 000 children (95% CI 5.1-11.1) in 2009 to 2.1/100 000 children (95% CI 1.1-4.1) in 2012. In 2014, 2 years after PCV13 was withdrawn from the universal vaccination program, the incidence of bacteremic CAP increased to 5.4/100 000 children (95% CI 3.5-8.4). We enrolled 113 cases and 113 controls. Streptococcus pneumoniae caused most of bloodstream infections (78%). Empyema was associated with bacteremia (P = .003, OR 3.6; 95% CI 1.4-8.9). Simple parapneumonic effusion was not associated with bacteremia. Incomplete PCV immunization was not a risk factor for bacteremic pneumonia.

Characterisation of microwave phase conjugate signal generation using nonlinearly loaded wire frequency selective surface (FSS)

Both experimental and theoretical information regarding the scattering and phase conjugate mixing properties of a 2D double-periodic array of wires loaded with nonlinear/linear lumped elements have been provided. An experimental means for assessing the phase conjugate energy production capability for the array is given. These investigations enable identification of the fundamental operational characteristics and underlying mechanisms associated with the production of phase conjugate energy by this type of artificial electromagnetic media. Means for enhancing the phase conjugate energy production capability of the structure by using additional linear lumped loads is examined theoretically and limits on the production of phase conjugate energy established. Theoretical far-field prediction of the behaviour of the structure indicates that retro-directive reflector action as well as negative refraction should be possible.