TPG图像压缩技术

TPG(tiny portable graphic)是基于AVS2视频编码标准推出的图像压缩技术,该图片格式压缩效率明显高于JPG、PNG、GIF等其他传统格式.介绍了TPG图像编码技术的编码原理以及技术特点,对比了TPG图片格式与传统图片格式的压缩效率,结果显示,TPG图片格式具有明显编码增益.     

Cage-like tris(salen)-type metallocryptand for cooperative guest recognition

A new cryptand-like tris(salen)-type ligand, H₆L, was synthesized. Metalation of this ligand with zinc(II) acetate gave a trinuclear metallohost [LZn₃] with a cage-like cavity surrounded by three metallosalen moieties. The metallohost [LZn₃] showed unique binding behavior to MOAc (M = Na, K, Rb, Cs) as an ion pair due to the cage-like cavity for cationic guests as well as the zinc(II) centers for anionic guests.     

Coincidence Point Theorems,Intersection Theorems and Saddle Point Theorems on FC-Spaces

In this paper, we first give the definitions of finitely continuous topological space and FC-subspace generated by some set, and obtain coincidence point theorem, whole intersection theorems and Ky Fan type matching theorems, and finally discuss the existence of saddle point as an application of coincidence point theorem.     

Construction of Liposomes Mimicking Cell Membrane Structure through Frame-Guided Assembly

The shape of eukaryotic cells is determined by the cytoskeleton associated with membrane proteins; however, the detailed mechanism of how the integral morphologies with structural stability is generated and maintained is still not fully understood. Here, based on the Frame-Guided Assembly (FGA) strategy, we successfully prepared hetero-liposomes with structural composition similar to that of eukaryotic cells by screening a series of transmembrane peptides as the leading hydrophobic groups (LHGs). It was demonstrated that the conformation and transmembrane mode of the LHGs played dominant roles during the FGA process. The FGA liposomes were formed with excellent stability, which may further provide evidence for the cytoskeleton–membrane protein–lipid bilayer model. Taking advantage of the biocompatibility and stability, the FGA liposomes were also applied to prepare novel drug delivery vehicles, which is promising in diagnostic imaging and cancer therapy applications.     

High general and special color rendering index white organic light-emitting device with bipolar homojunction emitting layers

High general and special color rendering index (CRI) together with gamut area index (GAI) is demanded for lighting source. In a tolerable Duv, an efficient warm white organic light-emitting device (WOLED) with a high CRI and GAI is developed by using a bipolar homojunction emitting layers, i.e., junction between different emitting layers with the same bipolar host material. At a low drive voltage of 4 V, the WOLED shows a high luminance of 1594 cd/m² and a power efficiency of 12.95 lm/W, and, it shows a high general CRI of 82, a special CRI R₉ of 75, an average of R₉ to R₁₂ of 69 and a GAI of 95. Besides, the WOLED shows relative stable color coordinates due to the elimination of the charges accumulation at interface between different emitting layers. And the current efficiency roll-off of the WOLED is also reduced due to the balance of carrier injection and transport in emitting layers.     

What can we learn from the tension between PLANCK and BICEP2 data?

Recently BICEP2 collaboration has announced the detection of the primordial gravitational waves at high confidence level.In light of the results of B-modes power spectrum from BICEP2 and using the basedΛCDM,a constraint on the tensor-to-scalar ratio r=0.20+0.07-0.05(68%C.L.)can be obtained,however,this result is in apparent tension with the limit on standard inflation models from the recent PLANCK measurement,r0.11(95%C.L.).Herein we review the recent progress on the cosmological studies after BICEP2 and discuss on different ways of reconciling the tension between PLANCK and BICEP2 data.We will discuss possible modifications on the standard cosmological model,such as including the running of scalar spectral index or other cosmological parameters correlated with inflationary cosmological parameters,or tilting the primordial power spectrum at large scales by introducing a cut off which can be predicted by bouncing cosmology.We will also comment on another possibility of generating extra B-modes of CMB polarization,namely by a non-zero polarization rotation angle during its transferring from the last scattering surface.     

Stimuli‐Triggered Growth and Removal of a Bioreducible Nanoshell on Nanoparticles

A new and easy method of stimuli‐triggered growth and removal of a bioreducible nanoshell on nanoparticles is reported. The results show that pH or temperature could induce the aggregation of disulfide‐contained branched polymers at the surface of nanoparticles; subsequently, the aggregated polymers could undergo intermolecular disulfide exchange to cross‐link the aggregated polymers, forming a bioreducible polymer shell around nanoparticles. When these nanoparticles with a polymer shell are treated with glutathione (GSH) or d,l ‐dithiothreitol (DTT), the polymer shell could be easily removed from the nanoparticles. The potential application of this method is demonstrated by easily growing and removing a bioreducible shell from liposomes, and improvement of in vivo gene transfection activity of liposomes with a bioreducible PEG shell.

     

Functional characterization of human oncoprotein gankyrin in Zebrafish

Gankyrin is an oncoprotein containing seven ankyrin repeats that is overexpressed in hepatocellular carcinoma (HCC). Gankyrin binds to Mdm2, which results in accelerated ubiquitylation via degradation of p53, and it also plays an important role in cell proliferation. However, little is known about the relationships between p53 levels, cell proliferation, and gankyrin over-expression. In order to investigate the influence of gankyrin protein on p53 and Mdm2 in a zebrafish model, we injected human gankyrin (hgankyrin) containing expression vectors (pCS2-hgankyrin, pCS2-hgankyrin-EGFP) into zebrafish embryos. To measure p53 and Mdm2 expression in hgankyrin-injected embryos, RT-PCR, Northern blot and in-situ hybridization and BrdU immunostaining were used. In addition, to know the effect of hgankyrin on cell proliferation in vitro, cell viability assays such as MTT, trypan blue staining and RT-PCR following transfection of hgankyrin-containing vector into HEK 293 cell line were performed. In vivo results indicated that p53 mRNA levels decreased but those of Mdm2 were not decreased in the presence of hgankyrin. These results suggest that gankyrin downregulates p53 expression and not Mdm2 expression. In the study of cell proliferation, BrdU-positive cells were predominantly increased in the head and tail regions in hgankyrin-injected zebrafish. Additional in vitro studies using trypan blue staining and MTT assay showed that gankyrin-expressing HEK 293 cells proliferated at a faster rate, indicating that gankyrin promotes cell proliferation. Our results demonstrate that hgankyrin overexpression downregulates p53 expression and promotes cell proliferation in zebrafish. Gankyrin may play an important role in tumorigenesis via its effects on p53 and cell proliferation.     

Steroids from the marine bryozoan <Emphasis Type="Italic">Bugula neritina</Emphasis>

One new compound, 3β-hydroxy-25-methoxy-(23E)-cholesta-5,23-diene (1), together with five known steroids, cholesteryl myristate (2), cholest-4-en-3-one (3), cholesterol (4), 3β,5α,9α-trihydroxy-(22E,24R)-ergosta7,22-dien-6-one (5), and 3β,5α,6β-trihydroxy-(22E,24R)-ergosta-7,22-diene (6), were isolated and identified from the marine bryozoan Bugula neritina.     

基于信道传播理论的多基地远程海底混响研究

针对浅海多基地远程海底混响, 以声传播的线性信道近似理论为基础, 通过确定海底界面的不均匀起伏特性, 对入射声波的远距离异地混响脉冲响应函数进行求解. 对非水平分层介质的浅海波导, 利用绝热简正波求解信道的传输函数, 得出了小角度斜坡海底的远程海底混响强度, 以下坡海底为例, 分析对比了不同海底倾角斜坡海底对远程异地混响强度及其衰减规律的影响. 理论仿真表明, 波导的传输效应对多基地远程海底混响强度的影响不可忽略.