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31.
张爱玲的小说中出现的母亲大多是有悖于伦理常识的形象,她们构成张爱玲式的"巫母群像",这种母亲形象表现出张爱玲对传统母性观的批判。此倾向的形成,与张爱玲对其母亲的情绪记忆密切相关。同时,张爱玲对母性的批判也暗含着她对女性及人性层面的理性思考与感性期待。  相似文献   
32.
生命的本能是能够把非实体信息转换成实体信息,并以此主动地支配和调节生命主体的行为,这应该就是生命奥秘的关键。心理信息内容作为实体信息被直接固化到神经子网络系统中,该实体信息能够完全替代外来信息表现心理内容。神经系统能够在心理信息运行的过程中自然而然地形成必要的记忆,人体内的精巧机制能够控制心理信息有目的地运行。  相似文献   
33.
主成分分析和长短时记忆神经网络预测水产养殖水体溶解氧   总被引:16,自引:11,他引:5  
为了提高水产养殖溶解氧预测的精度,提出了基于主成分分析(principal component analysis,PCA)和长短时记忆神经网络(long short-term memory,LSTM)的水产养殖溶解氧预测模型。首先通过主成分分析提取水产养殖溶解氧的关键影响因子,消除了原始变量之间的相关性,降低了模型输入向量维度;然后,在Tensorflow深度学习框架的基础上建立LSTM神经网络的水产养殖溶解氧预测模型;最后,利用该模型对浙江省淡水水产养殖研究所综合实验基地某池塘溶解氧进行验证。试验结果表明:该模型与BP神经网络等其他浅层模型相比,模型评价指标平均绝对误差、均方根误差和平均绝对误差分别为0.274、0.089和0.147,均优于传统的预测方法;该模型具有良好的预测性能和泛化能力,能够满足水产养殖溶解氧精确预测的实际需要,可以为水产养殖水质精准调控提供参考。  相似文献   
34.
目的检测酸樱桃汁对D-半乳糖致衰老小鼠模型学习记忆功能的影响.方法颈背部皮下注射D-半乳糖120 mg/(kg·d^-1)连续56 d建立亚急性衰老模型,同时灌胃给予不同剂量的酸樱桃汁进行治疗,治疗8周后,分别采用跳台实验、Morris水迷宫检测小鼠的学习记忆能力.结果跳台法检测结果显示:酸樱桃汁能延长D-半乳糖致衰老模型小鼠的潜伏期,减少错误次数;Morris水迷宫实验结果显示:酸樱桃汁能使D-半乳糖致衰老模型小鼠平均潜伏期明显缩短,跨过平台次数显著增加.结论酸樱桃汁能有效提高D-半乳糖致衰老小鼠的学习记忆能力.  相似文献   
35.
The Djungarian hamster and the Roborovskii hamster belong to the same genus of Phodopus. However, the Djungarian hamster is tame and shows sedative behavior, while Roborovskii hamster is not tame and shows high levels of locomotor activity. Hyperactivity occurs in animals with tameless behavior. Tameness or tamelessness behavior is very important because tameness helps for breeding and controlling as well as it enables a strong human‐animal bond. In the present study, we examined the relationships between activity levels and cognitive function in Djungarian and Roborovskii hamsters. Three types of behavioral tests were performed to analyze their activity levels, memory and leaning ability. The levels of L‐ and D‐amino acids and monoamines in the brain were then determined. Roborovskii hamsters showed significantly higher locomotor activity than Djungarian hamsters. Memory ability was not significantly different between the two hamsters, but Roborovskii hamsters showed lower learning ability. Brain levels of D‐serine which is related to enhancement in memory and learning ability, were significantly higher in Djungarian hamsters, but the reverse was true for brain dopamine and serotonin levels. These results suggest that these differences in brain metabolism may be related to the behavioral differences between the two hamsters.  相似文献   
36.
陈艳珍 《中国畜牧兽医》2017,44(4):1022-1026
试验旨在探讨蜂花粉醇提物(ethanol extracts from bee pollen,EEBP)对D-半乳糖诱导的衰老雄性小鼠学习、记忆和脑组织抗氧化能力的影响。以昆明种雄性小鼠为研究对象,按体重随机分为正常对照组、模型对照组和低、中、高剂量(400、800、1 600 mg/kg体重)EEBP组。除正常对照组外,其余各组小鼠每天颈背部皮下注射500 mg/kg体重 D-半乳糖0.2 mL,正常对照组注射等体积的生理盐水。EEBP组小鼠每天灌胃0.3 mL EEBP悬浮液,对照组小鼠灌胃等体积的蒸馏水,试验期56 d。采用Y型迷宫和跳台仪测试小鼠学习记忆能力,同时测定各组小鼠脑组织超氧化物歧化酶(superoxide dismutase,SOD)、谷胱甘肽过氧化物酶(glutathione peroxidase,GSH-Px)、过氧化氢酶(catalase,CAT)的活力及丙二醛(ma1ondialdehvde,MDA)的含量。结果表明,EEBP能显著降低D-半乳糖诱导的衰老小鼠Y型迷宫的学习次数,提高正确次数,延长跳台潜伏期,降低错误次数;提高衰老模型小鼠脑组织SOD、GSH-Px和CAT活性,降低MDA含量。以上结果说明EEBP可以改善D-半乳糖致衰老模型小鼠学习、记忆能力,提高脑组织的抗氧化能力,具有一定延缓脑衰老的作用。  相似文献   
37.
This study investigated whether four horses could recall the location of a food objective in a two-choice delayed response test. During testing, horses stood unrestrained in a station where they observed the delivery of 30 g of grain into one of two containers. They were then released and allowed to go toward a container under the following contexts: immediate release or delayed release of 5, 10, 15, 20, or 30 seconds. Results showed that horses remembered the correct objective not only under the immediate release condition but also for all delayed release conditions tested. Observational data were also collected to determine whether the horses were indeed relying on memory to solve the delayed response problems or whether they were using orienting cues to maintain focus on the correct container. These data showed that the horses did not maintain visual contact with the objective during many of the trials; instead, they attended to an assortment of distractions in the surrounding area. Contrary to a previous report in which horses could not accurately respond in a similar situation after 10-second delays, these findings suggest that at least some horses are not as limited with respect to their ability to recall things and have an adequate spatial short-term memory. Experimental design seems to play a significant role in the outcome of this type of research.  相似文献   
38.
构建动态能力有助于企业适应多变环境并维持竞争优势,而探求动态能力的微观机理有助于回答企业动态能力从何而来、如何构建和发展演化等基本问题。动态能力微观机理的一个重要部分是理清动态能力的构建主体及工作基础,高管团队理论提供了一个明确动态能力微观主体的崭新视角,基于这一视角,可进一步明确高管团队的工作基础是他们的社会网络与交互记忆系统。  相似文献   
39.
The prepolymer and the final polyurethane (PU) block copolymer were synthesized by reacting 4,4-methylene bis(phenylisocyanate) with poly(tetramethylene glycol) and the prepolymer with 1,4-butanediol as a chain extender, respectively, to investigate the relation between phase separation and it’s resulting properties. According to FT-IR data, the phase separation of hard and soft segments in the prepolymer and the PU block copolymer grew bigger by increasing the hard segment content, and the PU showed more dominant phase separation than the prepolymer. The heat of fusion due to soft segments decreased in both the prepolymer and the PU by increasing the hard segment content, whereas the heat of fusion due to hard segments increased in the PU did not appear in the prepolymers. The breaking stress and modulus of the prepolymer increased by increasing the hard segment content, and the elongation at break decreased gradually, and the PU showed the highest breaking stress and modulus at 58 % hard segment content. However, the best shape recovery of the PU was obtained at 47 % hard segment content due to the existence of proper interaction among the hard segments for shape memory effect. Consequently, the mechanical properties and shape memory effect of the PU were influenced by the degree of phase separation, depending on the incorporation of chain extender as well as the hard segment content.  相似文献   
40.
作物生长模型分布式并行调度方案的比较   总被引:1,自引:1,他引:0  
为了提高作物生长模型的计算速度,论文提出了多种分布式并行调度方案。综合分析了田块尺度下作物生长子模型以及子模型内部组分的数据依赖关系和计算流程。以流水线技术和分治策略为基础,分别在模型组分层、子模型层和驱动数据层设计了不同的分布式并行调度方案。在WCCS2003(Windows Compute Cluster Server 2003)组成的PC集群环境下,分别采用了OpenMP、MPI_OpenMP混合以及MPI编程模型实现了多种调度方案的并行模拟。并行加速比的实验分析表明,优化后的子模型层并行调度方案,在6个双核CPUs组成的PC集群上的平均加速比可达到8.2,更接近模型并行计算加速比的预测值。在分布式集群环境下,采用基于MPI的子模型层中等粒度的并行调度方案具有更快的计算速度,更适合于作物生长模拟系统。  相似文献   
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