非潮汐海洋运动对地球动力学扁率变化的贡献

通过考察全球海洋环流数值模型以及TOPEX Poseidon海洋测高数据 ,得到结论 :1 997 1 998年后的部分J2异常变化可能来自海洋环流变化导致的质量重新分布 ,具体地说是太平洋环流变化导致的从高纬地区向低纬地区的质量迁移 .本工作表明来自于海洋内部温盐效应的变化对J2 异常变化有重要贡献 。

Antiangiogenesis-Combined Photothermal Therapy in the Second Near-Infrared Window at Laser Powers Below the Skin Tolerance Threshold

Photothermal agents with strong light absorption in the second near-infrared(NIR-II)region(1000-1350 nm)are strongly desired for successful photothermal therapy(PTT).In this work,titania-coated Au nanobipyramids(NBP@TiO2)with a strong plasmon resonance in the NIR-II window were synthesized.The NBP@TiO2 nanostructures have a high photothermal conversion efficiency of(93.3±5.2)%under 1064-nm laser irradiation.They are also capable for loading an anticancer drug combretastatin A-4 phosphate(CA4P).In vitro PTT studies reveal that 1064-nm laser irradiation can efficiently ablate human lung cancer A549 cells and enhance the anticancer effect of CA4P.Moreover,the CA4P-loaded NBP@TiO2 nanostructures combined with PTT induce a synergistic antiangiogenesis effect.In vivo studies show that such CA4Ploaded NBP@TiO2 nanostructures under mild 1064-nm laser irradiation at an optical power density of 0.4 W cm?2,which is lower than the skin tolerance threshold value,exhibit a superior antitumor effect.This work presents not only the development of the NBP@TiO2 nanostructures as a novel photothermal agent responsive in the NIR-II window but also a unique combined chemo-photothermal therapy strategy for cancer therapy.

Enhanced anti-cancer effect of gambogic acid by gold nanorod-based delivery

OBJECTIVE Nanotechnology provides a novel strategy for the delivery of anticancer drugs.In this study,titanium dioxide coated gold nanorod(GNR/TiO_2) nanostructures were used as the drug carrier for gambogic acid in order to improve its anticancer effect.METHODS Biocompatibility and cellular uptake of GNR/TiO_2 nanostructures were studied in human glioblastoma U-87 MG cells.Cell viability was evaluated by ATP assay and calcein AM staining.Lyso Sensor Green DND-189 and Hoechst 33342 were used to analyze the intracellular location of GNR/TiO_2 nanostructures.The in vitro anti-cancer effect of gambogic acid loaded nanoparticles was compared with free drug.RESULTS The results showed that GNR/TiO_2 nanostructures are biocompatible,and they are localized at the intracellular acidic compartments of endosomes and lysosomes.The intracellular drug content delivered via GNR/TiO_2 nanostructures was 6 fold higher than the free form,thus dramatically enhancing the anticancer effect of gambogic acid.Furthermore,mild photothermal therapy also showed synergistic effect with the drug.CONCLUSION Our study suggested that GNR/TiO_2 nanostructures can be considered as a promising anticancer drug carrier.

Excitation of Annual Polar Motion by the Pacific,Atlantic and Indian Oceans

The global oceans play important roles in exciting the annual polar motion besides the atmosphere. However, it is still unclear about how large the regional oceans contribute to the annual polar motion. We investigate systemically the contributions of the Pacific, Atlantic and Indian Oceans to the excitation of the annual polar motion, based on the output data of ocean current velocity field and ocean bottom pressure field from ＂Estimating the Circulation and Climate of the Ocean （ECCO）＂ ocean circulation model over the period 1993-2005. The result shows that due to its particular location and shape, the Atlantic Ocean makes a less significant contribution to the x-component of the annual polar motion excitation than the Pacific and Indian Oceans, while all these three oceans contribute to the y-component of the annual polar motion excitation to some extent.

Nesterov’s Smoothing and Excessive Gap Methods for an Optimization Problem in VLSI Placement

In this paper,we propose an algorithm for a nonsmooth convex optimization problem arising in very large-scale integrated circuit placement.The objective function is the sum of a large number of Half-Perimeter Wire Length(HPWL)functions and a strongly convex function.The algorithm is based on Nesterov’s smoothing and excessive gap techniques.The main advantage of the algorithm is that it can capture the HPWL information in the process of optimization,and every subproblem has an explicit solution in the process of optimization.The convergence rate of the algorithm is Oe1=k2T;where k is the iteration counter,which is optimal.We also present preliminary experiments on nine placement contest benchmarks.Numerical examples confirm the theoretical results.