同型半胱氨酸对人脐静脉内皮细胞线粒体膜电位的影响

Objective:  To observe the changes of endothelial mitochondrial membrane potential（MMP）by building Hcy-induced endothelial impairment model in cultured human umbilical vein endothelial cells and to analyze the mechanism of Hcy-induced apoptosis.Methods: (1) Cultured HUVECs of term infant in vitro provide enough experimental materials. (2)The HUVECs are randomly divided into five groups: the control group does not add Hcy, the other groups add 0.01、0.1、1.0、3.0mmol/LHCY respectively, and put them together for 24 hours to detect the changes of MMP of the HUVECs at 3、6、12、24 hour.Results: There is no difference in the level of MMP in the HUVECs stimulated by HCY for 24 hours between the HCY0.01mmol/L group and the control group. Comparing with the control group,MMP reduces at 24 hour in the HCY0.1 mmol/L group ,at 6、12、24 hour in the HCY1.0 mmol/L group and at 3、6 hour(P<0.05）and obviously at 12、24 hour(P<0.01) in the HCY3.0 mmol/L group.In the same Hcy-induced group, MMP obviously reduces at 24 hour, ＞12h、6h、3h.At the same time, MMP obviously reduces at 3.0mmol/L Hcy-induced group, ＞1.0、0.1、0.01 mmol/L group and the control group.Conclusion: (1)HCY can injury endothelial function and induce apoptosis and it relates with concentration and time of HCY.(2) Mechanism of  Hcy- induced endothelial apoptosis may relates the reduction of MMP.目的 探讨同型半胱氨酸诱导人脐静脉内皮细胞线粒体膜电位(MMP)的变化，了解血管内皮细胞发生细胞凋亡的机制。方法 无菌采集正常足月剖腹产胎儿脐带进行人脐静脉内皮细胞培养，取对数生长的人脐静脉内皮细胞制成细胞悬液，加含1％胎牛血清（FCS）的培养基(DMEM)处理细胞24h，使细胞稳定、同步化。随机分成五组:（1）空白组：仅加含1％FCS的DMEM5ml。（2）HCY0.01mmol/L组：1％FCS的DMEM＋HCY终浓度为0.01 mmol/L 5ml。（3）HCY0.1 mmol/L组：1％FCS的DMEM＋HCY终浓度为0.1mmol/L 5ml。（4） HCY1.0 mmol/L组：1％FCS的DMEM＋HCY终浓度为1.0 mmol/L 5ml。（5）HCY3.0mmol/L组：1％FCS的DMEM＋HCY终浓度为3.0 mmol/L 5ml。继续培养24h，每组3个样本。结果 不9同浓度及时间HCY对HUVECs线粒体膜电位的影响:MMP在HCY0.01mmol/L组和空白对照组间无差异性变化；在HCY0.1 mmol/L组于24h时出现下降（P<0.05）；在HCY1.0mmol/L组于6h、12h、24h出现下降（P<0.05）；在HCY3.0mmol/L组于3h、6h有下降（P<0.05），12h、24h明显降低（P<0.01）。同一浓度HCY作用24h时MMP最低，依次＞12h、6h、3h。相同时间内，可以看到HCY浓度越高MMP降低越多，MMP在HCY3.0mmol/L组最低，依次＞1.0、0.1及0.01和空白组，结论 HCY可导致MMP发生改变，其浓度及作用时间是影响因素。（1）相同时间内，HCY浓度越高MMP降低越多。（2）同一浓度HCY作用时间越长MMP越低。

A New Approach for Large-Scale Scene Image Retrieval Based on Improved Parallel k

The rapid growth of digital images has caused the traditional image retrieval technology to be faced with new challenge. In this paper we introduce a new approach for large-scale scene image retrieval to solve the problems of massive image processing using traditional image retrieval methods. First, we improved traditional k-Means clustering algorithm, which optimized the selection of the initial cluster centers and iteration procedure. Second, we presented a parallel design and realization method for improved k-Means algorithm applied it to feature clustering of scene images. Finally, a storage and retrieval scheme for large-scale scene images was put forward using the large storage capacity and powerful parallel computing ability of the Hadoop distributed platform. The experimental results demonstrated that the proposed method achieved good performance. Compared with the traditional algorithms with single node architecture and parallel k-Means algorithm, the proposed method has obvious advantages for use in large-scale scene image data retrieval in terms of retrieval accuracy, retrieval time overhead, and computational performance (speedup and efficiency, sizeup, and scaleup), which is a significant improvement from applying parallel processing to intelligent algorithms with large-scale datasets

Structural, optical, and magnetic studies of manganese-doped zinc oxide hierarchical microspheres by self-assembly of nanoparticles

In this study, a series of manganese [Mn]-doped zinc oxide [ZnO] hierarchical microspheres [HMSs] are prepared by hydrothermal method only using zinc acetate and manganese acetate as precursors and ethylene glycol as solvent. X-ray diffraction indicates that all of the as-obtained samples including the highest Mn (7 mol%) in the crystal lattice of ZnO have a pure phase (hexagonal wurtzite structure). A broad Raman spectrum from as-synthesized doping samples ranges from 500 to 600 cm-1, revealing the successful doping of paramagnetic Mn2+ ions in the host ZnO. Optical absorption analysis of the samples exhibits a blueshift in the absorption band edge with increasing dopant concentration, and corresponding photoluminescence spectra show that Mn doping suppresses both near-band edge UV emission and defect-related blue emission. In particular, magnetic measurements confirm robust room-temperature ferromagnetic behavior with a high Curie temperature exceeding 400 K, signifying that the as-formed Mn-doped ZnO HMSs will have immense potential in spintronic devices and spin-based electronic technologies