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意识活动的神经生物学机制 被引量:2
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作者 韩中胜 祁金顺 《生理科学进展》 CAS CSCD 北大核心 2016年第5期339-345,共7页
人类神经系统可能是生物界最后有待攻克的功能系统之一,而尤以其中枢部分、特别是大脑的功能活动最为复杂和奥秘。目前,神经科学工作者对神经系统的一般功能及其生物学机制已有相当深入的了解,但仍然不能清楚地说明大脑是如何产生意识... 人类神经系统可能是生物界最后有待攻克的功能系统之一,而尤以其中枢部分、特别是大脑的功能活动最为复杂和奥秘。目前,神经科学工作者对神经系统的一般功能及其生物学机制已有相当深入的了解,但仍然不能清楚地说明大脑是如何产生意识、并以此为基础完成各种高级神经或精神活动的。本文主要从神经科学的角度出发,对近年来利用更为精确的脑电信号记录和功能性脑立体成像等先进技术在意识活动研究方面取得的进展作一概略介绍,并重点介绍意识研究领域中几个比较有影响的学说。 展开更多
关键词 意识 意识的神经性表征 意识的行为性表征 功能性脑成像 精神性意象 上行激活系统 泛脑神经元工作空间模型 动态芯理论 不做功模型网络
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睡眠、梦境的机制及其与学习记忆的关系 被引量:6
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作者 韩中胜 史均翰 《生理科学进展》 CAS CSCD 北大核心 2013年第6期409-414,共6页
睡眠是动物界的共同生理特征之一,表现为可逆性意识状态丧失。在人类每日的睡眠时间随年龄的增长而递减,总睡眠时间在一个人大约占去一生时间的三分之一。人的睡眠有很明显的周期性和时相性,其过程主要由体内固有的生物钟直接控制,但也... 睡眠是动物界的共同生理特征之一,表现为可逆性意识状态丧失。在人类每日的睡眠时间随年龄的增长而递减,总睡眠时间在一个人大约占去一生时间的三分之一。人的睡眠有很明显的周期性和时相性,其过程主要由体内固有的生物钟直接控制,但也受外界自然环境特别是光线强弱持续变化的调节。睡眠的生物学机理仍在研究探讨之中。梦境是伴随睡眠的一种神经心理活动过程,人人都有体验,大约和睡眠一样历史久远。但对其产生原理和生物学意义也是众说纷纭,没有共识。近年来的研究结果表明,睡眠的核心功能之一是进一步加工和处理当日大脑所接受的新信息,并将其选择性地转化为可长期保存的信息,储存在相应的大脑皮层功能区,即所谓的记忆信息巩固过程。本文简介睡眠和梦境这一对截然不同却又难以分开的生命现象的神经生理学基础、功能意义以及这方面的研究进展,并重点介绍睡眠期间所发生的学习记忆活动的研究进展。 展开更多
关键词 睡眠 梦境 记忆信息巩固
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Efficient AUV Path Planning in Time-Variant Underwater Environment Using Differential Evolution Algorithm 被引量:5
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作者 S.Mahmoud Zadeh D.M.W Powers +2 位作者 A.M.Yazdani K.Sammut A.Atyabi 《Journal of Marine Science and Application》 CSCD 2018年第4期585-591,共7页
Robust and efficient AUV path planning is a key element for persistence AUV maneuvering in variable underwater environments. To develop such a path planning system, in this study, differential evolution(DE) algorithm ... Robust and efficient AUV path planning is a key element for persistence AUV maneuvering in variable underwater environments. To develop such a path planning system, in this study, differential evolution(DE) algorithm is employed. The performance of the DE-based planner in generating time-efficient paths to direct the AUV from its initial conditions to the target of interest is investigated within a complexed 3D underwater environment incorporated with turbulent current vector fields, coastal area,islands, and static/dynamic obstacles. The results of simulations indicate the inherent efficiency of the DE-based path planner as it is capable of extracting feasible areas of a real map to determine the allowed spaces for the vehicle deployment while coping undesired current disturbances, exploiting desirable currents, and avoiding collision boundaries in directing the vehicle to its destination. The results are implementable for a realistic scenario and on-board real AUV as the DE planner satisfies all vehicular and environmental constraints while minimizing the travel time/distance, in a computationally efficient manner. 展开更多
关键词 Path planning Differential evolution Autonomous UNDERWATER vehicles EVOLUTIONARY algorithms OBSTACLE AVOIDANCE
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A pilot study of the association between genetic polymorphisms involved in estrogen signaling and infant male genital phenotypes
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作者 Sheela Sathyanarayana Shanna H Swan +5 位作者 Federico M Farin Hui-Wen Wilkerson Michael Bamshad Richard Grady Chuan Zhou Stephen M Schwartzy 《Asian Journal of Andrology》 SCIE CAS CSCD 2012年第5期766-772,共7页
Single nucleotide polymorphisms (SNPs) in genes that influence development of the male reproductive tract have been associated with male genitourinary abnormalities. However, no studies have tested the relationship ... Single nucleotide polymorphisms (SNPs) in genes that influence development of the male reproductive tract have been associated with male genitourinary abnormalities. However, no studies have tested the relationship between SNPs and intermediate phenotypes such as anogenital distance (AGD), anoscrotal distance (ASD) and penile width (PW). We tested whether 24 common SNPs in eight genes that influence male genital development were associated with intermediate phenotypes in 106 healthy male infants from the Study for Future Families. We used DNA from buccal smears and linear regression models to assess the relationship between anogenital measurements and SNP genotypes with adjustment for covariates. We found that the rs2077647 G allele, located in the coding region of estrogen receptor alpha (ESR1), was associated with a shorter AGD (P=0.02; -7.3 mm, 95% confidence interval (CI): -11.6 to -3.1), and the rs10475 T allele, located in the 3' untranslated region of activating transcription factor 3 (ATF3), was associated with a shorter ASD (-4.3 mm, 95% Ch -7.2 to -1.4), although this result was not significant (P=0.07) after controlling for multiple comparisons. We observed no association between PW and the SNPs tested. Minor alleles for two SNPs in genes that regulate estrogen signaling during male genital development were associated with AGD and ASD, although the significance of the association was marginal. Our findings suggest that AGD and ASD are influenced by heritable factors in genes known to be associated with frank male genital abnormalities such as hvpospadias and crvotorchidism. 展开更多
关键词 gene HYPOSPADIAS MALE phenotype polymorphism REPRODUCTIVE
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