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81.
现代生物工程技术是以基因工程、细胞工程、发酵工程酶工程为主体的高新技术。生产工程产业主要包括生物工程药业和生物工程农业两个重要部分。生物工程产业化都需要经过研究、开发、产业化和商业化四个步骤。生物工程产业发展经过了生物工程技术的突破阶段、完善和产业化的开始阶段、大规模产业化的开始阶段、大规模产业化的成熟阶段。其中第三阶段对我国的生物工程产业来说是为关键的。知识产权机会、商业机会为这个阶段我国生物工  相似文献   
82.
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   
83.
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   
84.
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   
85.
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   
86.
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   
87.
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   
88.
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   
89.
近似数量系统(Approximate Number System, ANS)指个体在不需要依赖于计算和数量符号的情况下, 对一组数量进行近似表征的系统。通过总结近十年来研究者们在ANS的遗传和神经基础、干预训练等方面取得的新进展, 指出未来应综合运用各种认知神经科学研究手段立足于ANS的基因和脑生理基础研究, 进一步揭示ANS的本质和内在发生发展机制, 并将有关研究发现运用到教育教学中, 对数学困难儿童进行干预, 以提高其数学能力和适应社会的能力。  相似文献   
90.
基因伦理的挑战在基因-检测、基因-治疗、基因-生殖、基因-克隆、基因-生态等五个层面展开,大致包括保护基因隐私、防止基因歧视,生殖细胞能否基因治疗,辅助生殖是否“扮演上帝”,克隆人,转基因的安全性等内容。同时,提出了基因决定论、实体论和主观论以及基因伦理走向何处等理论难题,需要认真研究和讨论。  相似文献   
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