Currently, land resources are becoming more and more constrained and structures are getting closer to each other. To investigate the seismic response of inter-story isolated structure to adjacent structure, models con...Currently, land resources are becoming more and more constrained and structures are getting closer to each other. To investigate the seismic response of inter-story isolated structure to adjacent structure, models considering no soil-structure interaction (SSI), considering soil-structure interaction (SSI), and considering structure-soil-structure interaction (SSSI) were established. Nonlinear seismic response comparative analysis was conducted by varying the spacing between adjacent structure and inter-story isolated structure, as well as the weight of adjacent structure, under different earthquake inputs, in order to obtain the structural response characteristics. The results indicate that the inter-story drift and inter-story shear of the inter-story isolated structure without considering SSI are smaller than those considering SSI and SSSI. The inter-story drift and inter-story shear of the inter-story isolated structure considering SSSI are further affected compared to that of the inter-story isolated structure considering only SSI. As the spacing between adjacent structure and inter-story isolated structure increases, the influence of adjacent structure on inter-story isolated structure decreases. The variation in the spacing between the two structures has a negligible effect on the isolation layer of the inter-story isolated structure. With the increase in the weight of adjacent structure, the influence of adjacent structure on inter-story isolated structure becomes more significant. The increasing weight of adjacent structure has an increasing effect on the Isolation layer of the inter-story isolated structure.展开更多
针对传统近邻传播聚类算法以数据点对之间的相似度作为输入度量,由于需要预设偏向参数p和阻尼系数λ,算法精度无法精确控制的问题,提出了一种跳跃跟踪麻雀搜索算法优化的交叉迭代近邻传播聚类方法.首先,针对麻雀搜索算法中发现者和加入...针对传统近邻传播聚类算法以数据点对之间的相似度作为输入度量,由于需要预设偏向参数p和阻尼系数λ,算法精度无法精确控制的问题,提出了一种跳跃跟踪麻雀搜索算法优化的交叉迭代近邻传播聚类方法.首先,针对麻雀搜索算法中发现者和加入者位置更新不足的问题,设计了一种跳跃跟踪优化策略,通过考虑偏好阻尼因子的跳跃策略设计大步长更新发现者,增加麻雀搜索算法的全局勘探能力和寻优速度,加入者设计动态小步长跟踪领头雀更新位置,同时,利用自适应种群划分机制更新发现者和加入者的比重,增加算法的后期局部开发能力和寻优速度;其次,设计基于扰动因子的Tent映射,在此基础上增加3个参数,使映射分布范围增大,并避免了陷入小周期点和不稳周期点;最后,引入轮廓系数作为评价函数,跳跃跟踪麻雀搜索算法自动寻找较优的p和λ,代替手动输入参数,并融合基于扰动因子的Tent映射优化近邻传播算法,交叉迭代确定最优簇数.使用多种算法聚类University of California Irvine数据集的10种公共数据集,仿真结果表明,本文提出的聚类算法与经典近邻传播算法、基于差分改进的仿射传播聚类算法、基于麻雀搜索算法优化的近邻传播聚类算法和进化近邻传播算法相比具有更优的搜索效率以及聚类精度.对国家信息数据进行了聚类分析,提出的方法更加准确有效合理,具有较好的应用价值.展开更多
A new method for establishing ES cell lines from 129/ter、C57BL/6J mice was set up which was characterized by the murine embryonic fibroblast cell(MEF) feeder, the medium of rat heart cell-conditioned medium(RH-CM)for...A new method for establishing ES cell lines from 129/ter、C57BL/6J mice was set up which was characterized by the murine embryonic fibroblast cell(MEF) feeder, the medium of rat heart cell-conditioned medium(RH-CM)for ES cells, and the consecutive digestion by the digestion liquid containing 1% serum. Every group of improved experiments was done with a control of routine method. The results showed that, compared with routine method, the improved way increased the ratio of ES cell lines of 129/ter mice from 11.8% to 33.3%, and of C57BL/6J from 3.7% to 13.3%. The difference is distinct. The passage culture of ES cells showed that, compared with medium added LIF, RH-CM not only inhibited the differentiation of murine ES cells, maintained its dipoild karyotype, but also promote its adherence growth. This kind of culture condition not only maintained the ES cells in an undifferentiated state and their normal dipoild karyotype, but also a series of other characteristics of totipotent embryonic stem cells during extended culture period.展开更多
In order to study the effects of controlled release nitrogen fertilizer （CRNF） application on rapeseed, a simulated experiment was carried out with 3 types of paddy soils in Dongting Lake area for 4 consecutive year...In order to study the effects of controlled release nitrogen fertilizer （CRNF） application on rapeseed, a simulated experiment was carried out with 3 types of paddy soils in Dongting Lake area for 4 consecutive years of applying CRNF under double rice cropping system after planting rapeseed crop in the fallow season. The effects of CRNF application on rapeseed yield, agronomic characters and soil fertility were studied in this paper. The results showed that CRNF application improved the growth of rapeseed plant and increased rapeseed yield of CRNF treatments in the purple calcareous clayed paddy soil （PCS） and alluvial loamy paddy soil （ALS） which respectively increased by 12.2% and 9.8% compared with applying urea, re- spectively. The rapeseed yield in 70% CRNF treatment obviously decreased com- pared with urea treatment. The contents of available N and organic carbon in soil increased by 25.0% and 3.2% in CRNF treatment in the ALS after rapeseed crop, respectively; and available N increased by 13.5% in the PCS. Both rapeseed yield and soil fertility in CRNF treatment and 70% CRNF treatment were lower than those in CK treatment in the reddish yellow clayed paddy soil （RYS）. The results al- so indicated that the functions of CRNF application on rapeseed yield increase and soil nitrogen fertility improvement were very obvious in the PCS and ALS.展开更多
目的:通过检测Ter细胞在不同发病阶段胶原诱导性关节炎(collagen-induced arthritis,CIA)小鼠脾脏中的数量变化及高峰期CIA小鼠脾脏Ter细胞与关节评分和T、B细胞亚群比例的相关性,探讨Ter细胞在CIA发生和发展中的作用,从而进一步深入理...目的:通过检测Ter细胞在不同发病阶段胶原诱导性关节炎(collagen-induced arthritis,CIA)小鼠脾脏中的数量变化及高峰期CIA小鼠脾脏Ter细胞与关节评分和T、B细胞亚群比例的相关性,探讨Ter细胞在CIA发生和发展中的作用,从而进一步深入理解类风湿关节炎的发病机制。方法: 6~8周的DBA/1小鼠进行CIA模型的诱导,二次免疫后开始对CIA小鼠进行关节评分。根据发病时间和关节评分将CIA分为发病早期、高峰期、晚期三个阶段。发病高峰期小鼠根据最终关节评分再分为高评分组(>8分)和低评分组(≤8分),流式细胞术检测na ve小鼠和各个阶段CIA小鼠脾脏中Ter细胞比例及发病高峰期CIA小鼠脾脏T、B 细胞亚群比例,并进行关联分析。结果:发病高峰期CIA小鼠脾脏Ter细胞比例较na ve小鼠明显升高(8.522%±2.645% vs . 1.937%±0.725%, P < 0.01),高评分组小鼠脾脏Ter细胞比例明显低于低评分组(6.217%±0.841% vs . 10.827%±0.917%, P < 0.01 )。高评分组小鼠脾脏Th1细胞比例明显高于低评分组(1.337%±0.110% vs . 0.727%±0.223%, P < 0.05 ),高评分组小鼠脾脏Th17细胞比例高于低评分组(0.750%±0.171% vs . 0.477%±0.051%, P =0.099),高评分组小鼠脾脏生发中心B(germinal center B,GC-B)细胞比例明显高于低评分组(1.243%±0.057% vs . 1.097%±0.015%, P < 0.05 )。相关性分析结果显示,发病高峰期CIA小鼠脾脏Ter细胞比例与CD4 + T、Th1、Th17、GC-B细胞比例均呈强负相关,与B10细胞比例呈强正相关,相关性均有统计学意义,提示这群细胞在CIA中可能具有保护作用。动态变化研究显示,随着疾病进展,发病晚期CIA小鼠脾脏Ter细胞比例较高峰期明显降低(0.917%± 0.588% vs . 8.522%±2.645%, P <0.001),进一步提示这群细胞在关节炎中的保护作用。结论: Ter细胞在发病高峰期CIA小鼠脾脏中明显增加,与小鼠关节评分及致病性免疫细胞比例呈负相关,与保护性免疫细胞比例呈正相关,发病晚期CIA小鼠Ter细胞比例明显降低,提示Ter细胞可能作为一种保护性细胞参与类风湿关节炎的发生和发展,但其具体作用及机制仍需后续进一步的体内及体外实验验证。展开更多
针对传统空气质量预测模型收敛速度慢,精度低的问题,提出一种基于变分模态分解(variational mode decomposition,VMD)和蜣螂优化算法(dung beetle optimizer,DBO)优化长短期记忆网络(long short term memory,LSTM)的预测模型。首先,针对...针对传统空气质量预测模型收敛速度慢,精度低的问题,提出一种基于变分模态分解(variational mode decomposition,VMD)和蜣螂优化算法(dung beetle optimizer,DBO)优化长短期记忆网络(long short term memory,LSTM)的预测模型。首先,针对AQI原始数据具有大量噪声的问题,使用VMD方法对非平稳信号进行模态分解以降低噪声对预测结果的影响从而获得多个不同特征的模态分量;其次,针对LSTM靠人工经验调参存在一定局限性,利用DBO算法对LSTM模型参数进行优化;最后,对分解后的各个子序列使用LSTM模型预测,将各个子序列进行叠加得到最后的预测结果。实验结果表明,VMD对非平稳数据的分解有助于提高预测精度,VMD-DBO-LSTM模型的性能较其他模型均有不同程度的提高,该模型预测的均方根误差为4.73μg/m^(3),平均绝对误差为3.61μg/m^(3),拟合度达到了97.8%。展开更多
文摘Currently, land resources are becoming more and more constrained and structures are getting closer to each other. To investigate the seismic response of inter-story isolated structure to adjacent structure, models considering no soil-structure interaction (SSI), considering soil-structure interaction (SSI), and considering structure-soil-structure interaction (SSSI) were established. Nonlinear seismic response comparative analysis was conducted by varying the spacing between adjacent structure and inter-story isolated structure, as well as the weight of adjacent structure, under different earthquake inputs, in order to obtain the structural response characteristics. The results indicate that the inter-story drift and inter-story shear of the inter-story isolated structure without considering SSI are smaller than those considering SSI and SSSI. The inter-story drift and inter-story shear of the inter-story isolated structure considering SSSI are further affected compared to that of the inter-story isolated structure considering only SSI. As the spacing between adjacent structure and inter-story isolated structure increases, the influence of adjacent structure on inter-story isolated structure decreases. The variation in the spacing between the two structures has a negligible effect on the isolation layer of the inter-story isolated structure. With the increase in the weight of adjacent structure, the influence of adjacent structure on inter-story isolated structure becomes more significant. The increasing weight of adjacent structure has an increasing effect on the Isolation layer of the inter-story isolated structure.
文摘针对传统近邻传播聚类算法以数据点对之间的相似度作为输入度量,由于需要预设偏向参数p和阻尼系数λ,算法精度无法精确控制的问题,提出了一种跳跃跟踪麻雀搜索算法优化的交叉迭代近邻传播聚类方法.首先,针对麻雀搜索算法中发现者和加入者位置更新不足的问题,设计了一种跳跃跟踪优化策略,通过考虑偏好阻尼因子的跳跃策略设计大步长更新发现者,增加麻雀搜索算法的全局勘探能力和寻优速度,加入者设计动态小步长跟踪领头雀更新位置,同时,利用自适应种群划分机制更新发现者和加入者的比重,增加算法的后期局部开发能力和寻优速度;其次,设计基于扰动因子的Tent映射,在此基础上增加3个参数,使映射分布范围增大,并避免了陷入小周期点和不稳周期点;最后,引入轮廓系数作为评价函数,跳跃跟踪麻雀搜索算法自动寻找较优的p和λ,代替手动输入参数,并融合基于扰动因子的Tent映射优化近邻传播算法,交叉迭代确定最优簇数.使用多种算法聚类University of California Irvine数据集的10种公共数据集,仿真结果表明,本文提出的聚类算法与经典近邻传播算法、基于差分改进的仿射传播聚类算法、基于麻雀搜索算法优化的近邻传播聚类算法和进化近邻传播算法相比具有更优的搜索效率以及聚类精度.对国家信息数据进行了聚类分析,提出的方法更加准确有效合理,具有较好的应用价值.
文摘A new method for establishing ES cell lines from 129/ter、C57BL/6J mice was set up which was characterized by the murine embryonic fibroblast cell(MEF) feeder, the medium of rat heart cell-conditioned medium(RH-CM)for ES cells, and the consecutive digestion by the digestion liquid containing 1% serum. Every group of improved experiments was done with a control of routine method. The results showed that, compared with routine method, the improved way increased the ratio of ES cell lines of 129/ter mice from 11.8% to 33.3%, and of C57BL/6J from 3.7% to 13.3%. The difference is distinct. The passage culture of ES cells showed that, compared with medium added LIF, RH-CM not only inhibited the differentiation of murine ES cells, maintained its dipoild karyotype, but also promote its adherence growth. This kind of culture condition not only maintained the ES cells in an undifferentiated state and their normal dipoild karyotype, but also a series of other characteristics of totipotent embryonic stem cells during extended culture period.
基金Supported by National Key Technology R&D Program Project in the 12~(th) Five-Year Plan:The 3~(rd) Hunan Special Project of Grain Bumper Science and Technology "The Integration and Demonstration of High-yield,Water-saving and Fertilizer-saving Techniques in the South Rice Area of Middle Reaches of Yangtze"(2013BAD07B11)Agro-scientific Research Programs in Public Interest "Study on the Change of Soil Fertility and Fertility Techniques in the Major Grain Producing Areas and the Demonstration"(201203030)International Cooperation Project"Study on the Efficient Nutrient Management Technology of Modern Double Cropping Rice in Hunan Province"(IPNI Hunan-18)~~
文摘In order to study the effects of controlled release nitrogen fertilizer （CRNF） application on rapeseed, a simulated experiment was carried out with 3 types of paddy soils in Dongting Lake area for 4 consecutive years of applying CRNF under double rice cropping system after planting rapeseed crop in the fallow season. The effects of CRNF application on rapeseed yield, agronomic characters and soil fertility were studied in this paper. The results showed that CRNF application improved the growth of rapeseed plant and increased rapeseed yield of CRNF treatments in the purple calcareous clayed paddy soil （PCS） and alluvial loamy paddy soil （ALS） which respectively increased by 12.2% and 9.8% compared with applying urea, re- spectively. The rapeseed yield in 70% CRNF treatment obviously decreased com- pared with urea treatment. The contents of available N and organic carbon in soil increased by 25.0% and 3.2% in CRNF treatment in the ALS after rapeseed crop, respectively; and available N increased by 13.5% in the PCS. Both rapeseed yield and soil fertility in CRNF treatment and 70% CRNF treatment were lower than those in CK treatment in the reddish yellow clayed paddy soil （RYS）. The results al- so indicated that the functions of CRNF application on rapeseed yield increase and soil nitrogen fertility improvement were very obvious in the PCS and ALS.
文摘目的:通过检测Ter细胞在不同发病阶段胶原诱导性关节炎(collagen-induced arthritis,CIA)小鼠脾脏中的数量变化及高峰期CIA小鼠脾脏Ter细胞与关节评分和T、B细胞亚群比例的相关性,探讨Ter细胞在CIA发生和发展中的作用,从而进一步深入理解类风湿关节炎的发病机制。方法: 6~8周的DBA/1小鼠进行CIA模型的诱导,二次免疫后开始对CIA小鼠进行关节评分。根据发病时间和关节评分将CIA分为发病早期、高峰期、晚期三个阶段。发病高峰期小鼠根据最终关节评分再分为高评分组(>8分)和低评分组(≤8分),流式细胞术检测na ve小鼠和各个阶段CIA小鼠脾脏中Ter细胞比例及发病高峰期CIA小鼠脾脏T、B 细胞亚群比例,并进行关联分析。结果:发病高峰期CIA小鼠脾脏Ter细胞比例较na ve小鼠明显升高(8.522%±2.645% vs . 1.937%±0.725%, P < 0.01),高评分组小鼠脾脏Ter细胞比例明显低于低评分组(6.217%±0.841% vs . 10.827%±0.917%, P < 0.01 )。高评分组小鼠脾脏Th1细胞比例明显高于低评分组(1.337%±0.110% vs . 0.727%±0.223%, P < 0.05 ),高评分组小鼠脾脏Th17细胞比例高于低评分组(0.750%±0.171% vs . 0.477%±0.051%, P =0.099),高评分组小鼠脾脏生发中心B(germinal center B,GC-B)细胞比例明显高于低评分组(1.243%±0.057% vs . 1.097%±0.015%, P < 0.05 )。相关性分析结果显示,发病高峰期CIA小鼠脾脏Ter细胞比例与CD4 + T、Th1、Th17、GC-B细胞比例均呈强负相关,与B10细胞比例呈强正相关,相关性均有统计学意义,提示这群细胞在CIA中可能具有保护作用。动态变化研究显示,随着疾病进展,发病晚期CIA小鼠脾脏Ter细胞比例较高峰期明显降低(0.917%± 0.588% vs . 8.522%±2.645%, P <0.001),进一步提示这群细胞在关节炎中的保护作用。结论: Ter细胞在发病高峰期CIA小鼠脾脏中明显增加,与小鼠关节评分及致病性免疫细胞比例呈负相关,与保护性免疫细胞比例呈正相关,发病晚期CIA小鼠Ter细胞比例明显降低,提示Ter细胞可能作为一种保护性细胞参与类风湿关节炎的发生和发展,但其具体作用及机制仍需后续进一步的体内及体外实验验证。
文摘阿尔茨海默病(AD)相关认知障碍是目前最主要的认知障碍类型,相比较皮质萎缩,皮质下白质变性被认为是AD相关认知障碍的关键病理特征。弥散张量成像(duffusion tensor imaging, DTI)和神经突方向离散度和密度成像(neurite orientation dispersion and density imaging, NODDI)技术是评估大脑白质微结构,检测大脑中神经纤维束扩散特征,揭示白质纤维束走行和完整性,量化白质通路微观结构特性,评估神经树突和轴突微观层面复杂性,提供神经纤维形态学信息的常用和新型方法。本文首先介绍白质微结构概念及位置,综述DTI和NODDI技术在AD相关认知障碍中白质微结构相关研究进展。
文摘针对传统空气质量预测模型收敛速度慢,精度低的问题,提出一种基于变分模态分解(variational mode decomposition,VMD)和蜣螂优化算法(dung beetle optimizer,DBO)优化长短期记忆网络(long short term memory,LSTM)的预测模型。首先,针对AQI原始数据具有大量噪声的问题,使用VMD方法对非平稳信号进行模态分解以降低噪声对预测结果的影响从而获得多个不同特征的模态分量;其次,针对LSTM靠人工经验调参存在一定局限性,利用DBO算法对LSTM模型参数进行优化;最后,对分解后的各个子序列使用LSTM模型预测,将各个子序列进行叠加得到最后的预测结果。实验结果表明,VMD对非平稳数据的分解有助于提高预测精度,VMD-DBO-LSTM模型的性能较其他模型均有不同程度的提高,该模型预测的均方根误差为4.73μg/m^(3),平均绝对误差为3.61μg/m^(3),拟合度达到了97.8%。
