一种分离结构与像素的二值图像压缩算法

文章提出了针对二值图像压缩的基于四叉树的分离结构与像素的算法,该算法通过一个阈值来决定对图像像素的合并,在合并过程中生成图像的四叉树结构,并根据结构中节点的取值来决定像素数据的存储,最后形成分离的结构数据与像素线性表。因为在数据分离过程中采用了去冗余处理,该算法对复杂图像的压缩比高于采用JBIG标准所产生的结果;又因为采用了由底至上的合并方案,使该算法有良好的时间和空间复杂性O(N)。由于压缩后的图像含有结构特征,算法可用于建立不同图像之间的联系,同时还适用于对气象、地貌等复杂图像的压缩。

无痛亚性甲状腺炎、Graves′病、激素合成不足性甲肿的核医学特征

目的 探讨无痛性亚急性甲状腺炎 (PST)、Graves′病 (GD)、激素合成不足性甲状腺肿 (HIG)的核医学特征。方法 用 IMMUL ITE法测定正常对照组、PST、GD和 HIG患者血清 TT3、TT4、TSH,并进行甲状腺 99m Tc O4- 平面显像 ,用感兴趣区分析法计算甲状腺与三对唾液腺的放射性比。结果 PST患者 TT3、TT4升高 ,TSH降低 ,摄 99m Tc功能降低 ;GD患者 TT3、TT4升高 ,TSH降低 ,摄 99m Tc功能增高 ;HIG患者 TT3、TT4降低 ,TSH增高 ,摄 99m Tc功能增高。结论 TT3、TT4、TSH激素水平与摄 99m Tc功能的不同分离现象是鉴别诊断 PST、GD和 HIG的核医学特征。

Prediction of the Aging of HTV Silicone Rubber Using Chemical Concentration and Polynomial Interpolation Approach

Predicting the lifetime of polymeric insulators is one of the most important research topics in studying the life cycle of high voltage insulators in the power transmission and distribution networks. HTV （high temperature vulcanized） silicone rubber is a high performance dielectric material used within electrical power equipment, in particular transmission and distribution insulators. In this paper, we proposed a new approach using the Newton＇s method and Lagrange method to predict the aging of HTV silicone rubber that are subjected to multiple stress conditions. Concentration of chemical elements such as carbon, oxygen, silicon and aluminum were obtained and evaluated using a SEM （scanning electron microscope） with EDS （energy dispersive X-ray spectroscopy）. Curve fitting using the Newton＇s and Lagrange interpolation methods yield useful linear interpolation equations that describe the aging characteristic of the specimens under study. This approach can be applied to predict the change in chemical concentration of polymeric insulators over the life cycle with good accuracy.

Co-delivery of doxorubicin and quercetin via mPEG-PLGA copolymer assembly for synergistic anti-tumor efficacy and reducing cardio-toxicity

Quercetin （Que） is a natural multifunctional bioflavonoid, and has shown great potential for reducing adverse side effects and enhancing antitumor efficacy of chemotherapeutic drugs. However, its clinical application is limited due to very low solubility and structural instability in physiological systems. Herein, we co-delivered hydrophobic quercetin and hydrophilic doxorubicin （Dox） by developing a biocompatible nanocarrier comprising of an amphiphilic polymer, methoxy poly（ethylene glycol） and poly（D, L-lactide-co-glycolide）, respectively. The antitumor and prophylactic efficacy of this system was evaluated in cellular and animal models. Our findings illustrated that the Dox-Que nanoparticulate formulation protected normal vascular endothelial cells from either free or nanoparticulate doxorubicin-induced cytotoxicity and increased cancer cell death. Compared with free doxorubicin and its nanoformulation, co-delivery of quercetin and doxorubicin using our nanosystem synergistically inhibited tumor growth, while maintaining normal levels of cardiac function indicators in serum and recovering the histopathological damages in heart tissue. This study demonstrates a promising strategy for enhancing anti-cancer drug efficacy and reducing chemotherapy-induced toxicity on normal nanoparticulate tissues.

Alleviative effect of quercetin on germ cells intoxicated by 3-methyl-4-nitrophenol from diesel exhaust particles

As a component of diesel exhaust particles, 3-methyl-4-nitrophenol （4-nitro-m-cresol, PNMC） is also a metabolite of the insecticide fenitrothion and imposes hazardous effects on human health. In the present study, the alleviative effect of a common antioxidant flavonoid quercetin on mouse germ cells intoxicated by PNMC was inves- tigated. Results showed that a single intraperitoneal injection of PNMC at 100 mg/kg induced severe testicular damage after one week. PNMC-treated mice showed a significant loss of germ cells （approximate 40% loss of round germ cells）. PNMC caused an increase of hydroxyl radical and hydrogen peroxide production and lipid peroxidation, as well as a decrease in glutathione level, superoxide dismutase and glutathione peroxidase activities. Furthermore, treatment of PNMC increased expression of the pro-apoptotic protein Bax and decreased expression of the anti-apoptotic protein BcI-XL in germ cells. In addition, testicular caspase-3 activity was significantly up-regulated and germ cell apoptosis was significantly increased in the PNMC-treated mice. In contrast, combined administration of quercetin at 75 mg/kg significantly attenuated PNMC-induced testicular toxicity. These results indicate that the antioxidant quercetin displays a remarkable protective effect on PNMC-induced oxidative damage in mouse testes and may represent an efficient supplement to attenuate reproductive toxicity by environmental toxicants to ensure healthy sperm production.

Parameterization of Nuclear Hulthén Potential for Nucleus-Nucleus Elastic Scattering

In contrast to Gaussian or Woods-Saxon potential a two-term four parameter nuclear Hulthdn type inter- action is considered to describe the a-a, t-a He and t=3 H systems. By exploiting the phase function method, scattering phase shifts are computed up to ELb -- 100 MeV for the a-a system and ELab = 15 MeV for a-3He and a-3H systems. The S-wave phase shift 5o for the system tends to 2n and 53/2_ for thea-3He system tends to n, in the limit of zero energy. Reasonable agreements in phase shifts with the standard data are obtained with this simple potential model except for the 5/2- states of a-3He and a-3H systems, With an additional energy-dependent correction factor to our potential, a good agreement with experimental data is obtained for 5/2- states. We have also compared our results with the convenient Born approximations.