716 research outputs found
Case study on support of foundation pit near Qiantang River
通过对临钱塘江某工程基坑支护实例的分析与论述,探讨了当基坑开挖具有较强补水边界、基坑内部地下水较高时,其合理的设计与施工方案。现场监测结果表明,本文提出的支护设计和施工方案是切实可行的。Based on the description and analysis of an example of foundation pit support engineering near the Qiantang River,the reasonable design and construction schemes were discussed for the foundation pit which has high level of ground water due to the seepage flow pressure.The proposed support design and construction scheme were proven to be effective by on-the-spot monitoring results
Algorithm of information hiding based on ICA for image
独立分量分析(ICA)是一种基于高阶统计量的信号分析方法,它可以找到隐含在数据中的独立分量,已广泛应用于信号处理领域。信息隐藏是一种新兴的技术,其目的在于将秘密信息隐藏于另一非机密信息中。本文提出一种新的信息隐藏技术,即将ArnOld置乱后的秘密图像嵌入到载体图像中,再利用ICA算法从中提取出秘密图像。仿真结果表明该算法有效可行。Independent Component Analysis(ICA)was widely used in signal processing,which is a signal analysis method based on signal's high order cumulants,it can find out the latent independent components in data.Information hiding technology is a new method in information processing;the hiding information is embed in public information.This paper introduces an algorithm based on ICA for information technology.This paper embeds the cryptogrammic hiding image in public image,then using ICA algorithm to abstract the hiding image.The results of emulation indicate this algorithm is available and feasible
Foundation pit precipitation design and construction analysis for two-flank shaped "urban balcony" project of Qianjiang New City
针对杭州钱江新城两翼"城市阳台"工程的基坑具有开挖面大,场地内地下水位较高,基坑南侧由于濒临钱塘江而具有极强的补水边界等特点,探讨和比较了可应用于该场地的基坑降水设计和施工方案。施工效果和现场监测表明,应用本文所述的降水方案达到了预期效果,保证了基坑开挖顺利施工。For the two-flank shaped"urban balcony"project of Qianjiang New City of Hangzhou City,in view of such characteristics as large excavation area for pit foundation,high ground water level within the site,and there is a strong make-up water limit as the south side of the foundation pit faces Qiantang river,the foundation pit precipitation design and construction scheme are discussed and compared.The construction result and the site monitoring showed that by application of the abovementioned precipitation scheme,the expected result was reached,and the smooth excavation and construction of the pit foundation was ensured
MiRNA-138抑制JNK/p38MAPK通路保护新生大鼠心肌细胞凋亡
【目的】探究miRNA-138抑制JNK/p38MAPK通路保护新生大鼠心肌细胞凋亡。【方法】收集2018年1月至12月急性心肌缺血患者全血样本33例,另招募同期体检健康者全血样本33例作对照;构建新生大鼠缺血再灌注(I/R)模型,将40只新生大鼠随机分为空白对照组(Control)、模型组(I/R model)、阴性对照组(注射无序序列,Scramble)及miRNA-138过表达组(Ad-miRNA-138),每组10只。采用qRT-PCR检测全血和心肌组织中miRNA-138、Bcl2及Bax mRNA的表达,电生理记录仪检测大鼠血流动力学指标水平,HE染色观察大鼠心肌组织病理损伤,免疫组法化检测心肌组织中Casapse-3的表达,TUNEL染色观察大鼠心肌组织细胞的凋亡情况,ELISA法检测心肌组织活性氧(ROS)的含量,Western blotting检测JNK/p38MAPK通路蛋白的表达。【结果】与健康对照相比,急性心肌缺血患者全血中miRNA-138的水平显著降低(P<0.05);与I/R模型组相比,Ad-miRNA-138组大鼠心肌细胞间隙更小、排列更整齐性、结构更完整,miRNA-138表达、心功能指标+dp/dtmax、HR、LVSP及Bcl2/Bax水平显著上升,凋亡细胞数、Caspase-3阳性表达细胞率、ROS、p-p38/p38、p-c-jun/c-jun及p-JNK1/2/JNK1/2显著下调(P<0.05)。【结论】miRNA-138可通过抑制JNK/p38MAPK通路,抑制大鼠心肌细胞的凋亡,并减轻活性氧损伤,从而保护新生大鼠心肌细胞
Blind caption watermarking scheme based on ICA and DCT
标注水印为数字多媒体的便捷使用提供了一种新的途径。提出了1种结合独立分量分析(ICA)和离散余弦变换(dCT)的数字图像标注水印盲提取算法。该算法先将载体图像重采样成2个极为相似的子图,再分别将其分解成互不重叠的8x8子块,并进行离散余弦变换,接着将经过置乱后的水印嵌入到余弦变换的中频系数上,最后进行逆余弦变换得到嵌有水印的图像。采用ICA技术进行水印提取。实验表明,该算法有效可行。Caption watermarking is a new convenient way to use the digital multimedia.A blind scheme of digital image caption watermarking based on the independent component analysis(ICA) and discrete cosine transform(DCT) is proposed.Firstly,the cover image is sampled into two very similar sub-images.Secondly,the sub-images are decomposed into non-overlapping 8×8 blocks.Thirdly,these blocks are transformed into discrete cosine domain.Then the watermark is embedded into its middle frequency coefficient which has been rearranged by Scramble before embedded.Finally,we get image which is embed watermark by IDCT.It use the technique of ICA when the watermark is extracted.The results of emulation indicate this algorithm is available and feasible.福建省自然科学基金(2009J01301)资
Rate Control Strategy Based on the Distributed Character of DCT Coefficients
根据缓存器的状态和信道速率为待编码帧在图像层上预分配目的视频编码比特数 ,使用DCT系数分布特性来表征图像特性 ,继而为帧内每一具体宏块选定最佳量化因子 ,提出了基于DCT系数分布特性的码率控制策略 .并分析了算法的复杂度 ,提出了改进策略 .模拟实验表明 ,该码率控制策略能有效地减少、避免缓存器出现上、下溢的情况 ,而输出码率趋于稳定 .提高了重建图像的信噪比 ,并且在视频图像质量没有明显失真的前提下 ,改进了计算复杂度 .Rate control strategy based on the distributed character of DCT coefficients is proposed , we allocates the target number of bits firstly on picture layer based on the status of the buffer and the channel rate, and then denotes the characteristics of the picture by the distributed characteristics of the DCT coefficients and select a best quantized parameter for every macroblock in a frame. The complexity of the algorithm is analyzed and an improved method is proposed. The experiment shows that this rate control strategy can effectively reduce and avoid the overflow and underflow of the encoder buffer, and the output bit rates tend to stabilization. The PSNR of the reconstructed picture is raised, and the complexity of the algorithm is improved with no visible distortion in video image.安徽省教委自然科学基金资助项目 (99j10 0 18
束缚和异氟烷麻醉对大鼠心率变异性及HPA轴影响的比较
目的为了观察束缚固定和异氟烷(流量:0.8 L,浓度:1.5%)麻醉状态中大鼠的心率变异性的变化;并通过比较9天每天30 min束缚干预和异氟烷麻醉对大鼠的体重、痛阈以及与HPA轴相关激素的影响,来评估长期使用异氟烷麻醉和束缚固定对大鼠应激程度的影响,选择更适宜的大鼠固定方法,为基础医学的实验方法提供重要的参考。方法 SD大鼠随机分为3组:空白组,束缚组,异氟烷麻醉组。急性实验通过记录大鼠心电图15 min,观察束缚固定和异氟烷麻醉情况下大鼠心率,心率变异性的变化。慢性实验中比较连续干预9天(30 min/d)前后3组大鼠体重、痛阈变化以及与应激状态相关激素含量的变化。结果 1)急性试验:与空白组大鼠相比,束缚干预和异氟烷麻醉均造成大鼠心率显著增加,具有统计学意义(P 0.05)。结论以上结果提示:低浓度的异氟烷造成麻醉中大鼠心率增加,心率变异性下降,产生以交感兴奋为主的自主神经功能状态改变。多次束缚固定易造成大鼠HPA轴激活,产生慢性应激的效应。在长期需要固定动物的实验中,与束缚固定相比异氟烷麻醉是更好的固定方法。国家自然科学基金(81674083
Effect of Ethanol Extract from Camellia Oleifera Abel. on Blood Glucose in Type 2 Diabetic Mice
目的筛选油茶(Camellia oleifera Abel.)降低2型糖尿病小鼠血糖的有效部位。方法采用腹腔注射烟碱、链脲霉素诱导的2型糖尿病小鼠模型,应用超声提取法分别获得油茶叶、果、籽的乙醇提取物,筛选降低血糖的有效部位。结果阳性药罗格列酮每日灌胃剂量10mg/kg·BW,连续灌胃21d后,降低了2型糖尿病小鼠血糖。分别灌胃油茶叶、油茶果、油茶籽乙醇提取物,按每日剂量100mg/kg·BW连续灌胃21d后,均在一定程度上降低2型糖尿病小鼠血糖,油茶籽乙醇提取物对口服葡萄糖耐受试验(Oral glucose tolerance test,OGTT)作用最明显。与对照组相比,1μM和2μM的阳性药罗格列酮均能明显促进3T3-L1前脂肪细胞分化;油茶籽乙醇提取物在0.5μg·m L-1和1μg·m L-1浓度下也体现出促进分化的活性。结论油茶籽乙醇提取物降低了2型糖尿病小鼠的血糖,促进了3T3-L1前脂肪细胞的分化,但其具体作用机制尚需深入研究。OBJECTIVE To investigate effective parts possessing property of lowering blood glucose in type 2diabetic mice from Camellia oleifera Abel. METHODS Leaf,fruit and seed ethanol extract of C. oleifera were obtained through ultrasonic extraction,and were subsequently subject to type 2 diabetic mice model induced by intraperitoneal injection of streptozocin and nicotine. RESULTS In accordance with the positive drug rosiglitazone by intragastric administration once daily dose of 10 mg / kg·BW,continuous intragastric administration for 21 days,blood glucose in type 2 diabetic mice was reduced. In accordance with a daily dose of 100 mg / kg·BW leaf,fruit and seed ethanol extract of C. oleifera,continuous intragastric administration for 21 days respectively,in a certain extent,blood glucose in type 2 diabetic mice was reduced. Moreover,effect of seed ethanol extract on blood glucose and oral glucose tolerance test( OGTT) is the most obvious. Compared with control group( treated with insulin),1μM and 2μM of positive drug rosiglitazone can significantly promote differentiation of 3T3-L1 pre-adipocytes,C. oleifera seed ethanol extract as the most effective part for lowing blood glucose at 0. 5μg·m L~(-1) and 1μg·m L~(-1)concentration also promoted 3T3-L1 pre-adipocyte differentiation. CONCLUSION It was suggested that C. oleifera seed ethanol extract lowered blood glucose in type 2 diabetic mice and enhanced differentiation of 3T3-L1 pre-adipocytes,but the specific mechanism needs further study.福建省教育厅中青年教师教育科研项目杰青项目JA14421;福建省教育厅中青年教师教育科研项目JA13425; 厦门市科技局科技计划高校创新项目3502Z20143026;厦门市科技局科技计划项目3502Z20144031; 福建省自然科学基金计划资助项目2015J01065; 福建省科技厅自然科学基金青年创新项目2014D008; 福建省卫生系统中青年骨干人才培养项目基础项目2015-ZQN-JC-45; 厦门市卫生和计划生育委员会资助研究经费; 厦门医学高等专科学校科研基金Z2013-12;Z2013-2
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