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91.
Charles F. Smith 《Zygon》2000,35(1):181-187
DNA is an important agent not only in chemistry and biology but also in technology and modern culture. A number of books approach the double helix from different angles. These perspectives include (1) the science of DNA and genetics; (2) genetic engineering; (3) the ethics of manipulating genetic material; and (4) DNA in culture and religion. Various views of DNAprovide insights into human nature beyond its molecular composition.  相似文献   
92.
基于遗传算法的模糊综合评价在心理测量中的应用   总被引:1,自引:0,他引:1  
余嘉元 《心理学报》2009,41(10):1015-1023
提出了运用模糊数学对利克特量表数据进行分析的方法, 探讨了人们在进行模糊综合评价时, 所采用的算子和对各个自变量的权重分配, 并且运用遗传算法(GA)来确定相关的权重。以大学生对康师傅红烧牛肉面的评价数据为例, 运用基于遗传算法的模糊综合评价方法, 发现男生采用了“最大最小”合成算子, 女生采用了“有界和、取小”合成算子。研究结果表明, 基于遗传算法的模糊综合评价方法可以对利克特量表的心理测量数据进行有效的分析。  相似文献   
93.
Executive function is a broad construct that encompasses various processes involved in goal‐directed behaviour in non‐routine situations (Banich, 2009). The present study uses a sample of 560 5‐ to 16‐year‐old twin pairs (M = 11.14, SD = 2.53): 219 monozygotic twin pairs (114 female; 105 male) and 341 dizygotic twin pairs (136 female, 107 male; 98 opposite sex) to extend prior literature by providing information about the factor structure and the genetic and environmental architecture of the Behavior Rating Inventory of Executive Function (BRIEF; Gioia et al., 2000, Child Neuropsychol., 6, 235; Gioia et al., 2000, Behavior rating inventory of executive function, Lutz, FL: Psychological Assessment Resources), a multifaceted rating scale of everyday executive functions. Phenotypic results revealed a 9‐scale, 3‐factor model best represents the BRIEF structure within the current sample. Results of the genetically sensitive analyses indicated the presence of rater bias/contrast effects for the Initiate, Working Memory, and Task‐Monitor scales. Additive genetic and non‐shared environmental influences were present for the Initiate, Plan/Organize, Organization of Materials, Shift, and Monitor and Self‐Monitor scales. Influences on Emotional Control were solely environmental. Interestingly, the aetiological architecture observed was similar to that of performance‐based measures of executive function. This observed similarity provided additional evidence for the usefulness of the BRIEF as a measure of ‘everyday’ executive function.  相似文献   
94.
Object-location memory (OLM) enables us to keep track of the locations of objects in our environment. The neurocognitive model of OLM (Postma, A., Kessels, R. P. C., & Van Asselen, M. (2004). The neuropsychology of object-location memory. In G. L. Allen (Ed.), Human spatial memory: Remembering where (pp. 143–160). Mahwah, NJ: Lawrence Erlbaum, Postma, A., Kessels, R. P. C., & Van Asselen, M. (2008). How the brain remembers and forgets where things are: The neurocognition of object-location memory. Neuroscience & Biobehavioral Reviews, 32, 1339–1345. doi:10.1016/j.neubiorev.2008.05.001) proposes that distinct brain regions are specialised for different subprocesses of OLM (object processing, location processing, and object-location binding; categorical and coordinate OLM; egocentric and allocentric OLM). It was based mainly on findings from lesion studies. However, recent episodic memory studies point to a contribution of additional or different brain regions to object and location processing within episodic OLM. To evaluate and update the neurocognitive model of OLM, we therefore conducted a systematic literature search for lesion as well as functional neuroimaging studies contrasting small-space episodic OLM with object memory or location memory. We identified 10 relevant lesion studies and 8 relevant functional neuroimaging studies. We could confirm some of the proposals of the neurocognitive model of OLM, but also differing hypotheses from episodic memory research, about which brain regions are involved in the different subprocesses of small-space episodic OLM. In addition, we were able to identify new brain regions as well as important research gaps.  相似文献   
95.
Filicide is the killing of a ward by a parent. Relative to many other types of homicide, filicide is an infrequent event. Filicide followed by the offender's suicide is less frequent still. The contexts and circumstances surrounding filicide‐suicide may nevertheless provide insight into parental psychology. Some research suggests, for example, that filicidal genetic parents are more likely to commit suicide than are filicidal stepparents. Five hypotheses are tested for this study, using a database that includes incident‐level information on over 22,000 homicides committed in Chicago during the years 1965–1994. Findings do not support the hypothesis of differential risk of suicide following filicide by genetic parents and stepparents. Previous work is replicated, indicating that: (1) filicides that include multiple victims are more likely to end in the offender's suicide than are filicides that include a single victim, (2) parents are more likely to commit suicide following a filicide of an older child than a filicide of a younger child, (3) older parents, relative to younger parents, are more likely to commit suicide following filicide, and that (4) fathers, relative to mothers, are more likely to commit suicide following filicide. Discussion suggests future directions for research that can inform our understanding of filicide and of filicide‐suicide. Aggr. Behav. 00:000–000, 2005. © 2005 Wiley‐Liss, Inc.  相似文献   
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98.
Nowadays, intelligent connectionist systems such as artificial neural networks have been proved very powerful in a wide area of applications. Consequently, the ability to interpret their structure was always a desirable feature for experts. In this field, the neural logic networks (NLN) by their definition are able to represent complex human logic and provide knowledge discovery. However, under contemporary methodologies, the training of these networks may often result in non-comprehensible or poorly designed structures. In this work, we propose an evolutionary system that uses current advances in genetic programming that overcome these drawbacks and produces neural logic networks that can be arbitrarily connected and are easily interpretable into expert rules. To accomplish this task, we guide the genetic programming process using a context-free grammar and we encode indirectly the neural logic networks into the genetic programming individuals. We test the proposed system in two problems of medical diagnosis. Our results are examined both in terms of the solution interpretability that can lead in knowledge discovery, and in terms of the achieved accuracy. We draw conclusions about the effectiveness of the system and we propose further research directions.  相似文献   
99.
基因多态性对情绪调节神经回路的影响   总被引:1,自引:0,他引:1  
随着脑成像和基因分析等新技术手段的综合运用, 情绪调节的神经生物学基础研究有了很大进展。综述相关研究表明: 情绪调节的神经回路涉及背侧-腹侧前额叶、前额叶-杏仁核和皮层-边缘系统的相互作用, 这些神经回路受到5-羟色胺传运体(5-hydroxytryptamine transporter, 5-HTT)、儿茶酚转甲酶 (Catechol-O-methyltransferase, COMT)和色氨酸羟化酶2(Tryptophan hydroxylase 2, TPH2)等基因变异, 以及不同基因多态之间交互作用的影响。情绪调节神经回路的功能出现障碍将导致情绪疾病的产生。  相似文献   
100.
发展性阅读障碍是一种遗传性很高的认知功能缺陷, 运用关联分析对其遗传机制进行研究是近年来的新趋势。从研究方法的视角可以将现有的关联分析研究归为以下三类:家系法研究、病例-控制法研究和数量性状关联分析研究。阅读障碍关联分析研究的新趋势主要体现在与全基因组扫描技术、神经成像技术以及基因功能研究的结合上, 促进了从“基因-大脑-行为”层面对发展性阅读障碍的遗传机制进行理解。  相似文献   
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