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41.
转基因技术安全性的生态伦理浅析   总被引:6,自引:0,他引:6  
以转基因技术为基础的生物技术是本世纪最具影响力的高新技术产业带。转基因技术在农业、食品、医药、环保等方面有广泛应用,它给人类社会的发展带来巨大的经济效益和社会效益的同时,也存在着潜在危险,即有可能影响生态环境,危害人类健康。本文试图从生态伦理的角度来思考转基因技术的安全性问题。  相似文献   
42.
A striking feature of nanocrystalline (NC) materials prepared by different techniques is the variation of lattice strain present in the crystallites. A simple model is proposed to account for this phenomenon, which allows the establishment of a quantitative relationship describing the dependence of the crystal lattice strain on the grain size. Good agreement between theoretical and experimental data indicates that the stress field, induced by the excess volume in grain boundaries, is the dominant source of the lattice strain.  相似文献   
43.
从法理学的角度来说,医患法律关系应该属于独立的医事法调整的对象,属于社会法法域.这一判断既有其理论依据又颇具实践价值:它能为订立独立的医事法提供理论基础,为运用多元化机制解决医疗纠纷提供理论支点,为构建和谐医患关系提供视角转换,即从“医—患”二维视角转换为“国—医—患—社”四维视角.  相似文献   
44.
This is a study of the development trend of creative scientific problem finding (CSPF) ability of a sample of 1,367 elementary, middle, and high school students in two Chinese cities. Students were instructed to generate science related questions in both open and closed conditions with responses scored for Fluency, Flexibility, and Originality. Results suggest that CSPF ability has a developmental trend characterized by a significant leap in the 5th grade, followed by a steady advance until it peaked in the 8th grade, and then declined and stabilized in the high school years (9th–11th grades). No difference between male and female students was found. The type of instruction showed significant differential influence on CSPF and its development.  相似文献   
45.
People are very adept at perceiving biological motion (e.g., Johansson, 1973 Johansson, G. (1973). Visual perception of biological motion and a model for its analysis. Perception & Psychophysics, 14(2), 201211.[Crossref], [Web of Science ®] [Google Scholar]). This ability has been an essential life skill to members of this social species. The human niche during the ice age was socially coordinated hunting for big game. Being able to judge the location targeted by the throw of a conspecific would be a valuable perceptual ability that we now study to investigate 2 competing theories of biological motion perception: Common Coding (CC; Prinz, 1997 Prinz, W. (1997). Perception and action planning. European Journal of Cognitive Psychology, 9(2), 129154.[Taylor & Francis Online], [Web of Science ®] [Google Scholar]) and Kinematic Specification of Dynamics (KSD; Runeson & Frykholm, 1983 Runeson, S., & Frykholm, G. (1983). Kinematic specification of dynamics as an informational bias for person-and-action perception: Expectation, gender recognition, and deceptive intent. Journal of Experimental Psychology: General, 112, 585615.[Crossref], [Web of Science ®] [Google Scholar]). The 2 theories diverge in attributing perceptual ability to either motor or visual experience, respectively. To test predictions of the CC theory, we performed 3 experiments to manipulate observers' specific motor experience while they judged the targeted location of throwing by watching point-light displays. In Experiment 1, we tested whether the identity of the thrower in the display mattered. In Experiment 2, we tested whether the motor expertise of the observer mattered. In Experiment 3, we tested whether the gender/style of throwing demonstrated by the point-light thrower mattered. The combined results failed to support CC theory, suggesting that motor experience is not required for the perception of action. Because all participants judged the target location of throwing quite well, KSD theory suggests that the kinematic information available in the displays may have enabled the perception. We performed Experiment 4 to analyze the information. We found that the judgment pattern exhibited by the observers in both Experiments 1 and 2 was well predicted by the KSD theory. Thus, we concluded that the perception of biological motion is enabled by visual information and improved by visual experience.  相似文献   
46.
This study aimed to investigate the mechanisms underlying joke comprehension using event‐related potentials (ERPs). Fourteen healthy college students were presented with the context of a story without its joke or nonjoke ending, and then, when the story ending was presented, they were asked to make a funny/unfunny judgment about these endings. The behavioral results showed that there was no significant difference between funny and unfunny items, which meant that subjects could understand funny items as easily as unfunny ones. However, the ERP results showed that funny items initially elicited a more negative ERP deflection (N350–450) over frontocentral scalp regions. Dipole analysis localized the generators in the left temporal gyrus and the left medial frontal gyrus; it is suggested that these areas might be involved in detecting the incongruent element in joke comprehension. Between 600 and 800 ms, funny items subsequently elicited a more negative ERP deflection (N600–800) over frontocentral scalp regions and a more positive ERP deflection (P600–800) over posterior scalp regions. Dipole analysis localized the generator in the anterior cingulate cortex (ACC), an area involved in the breaking of mental set/expectation and the forming of novel associations. Finally, funny items elicited a more positive ERP deflection (P1250–1400) over anterior and posterior scalp regions. Dipole analysis localized the generators in the middle frontal gyrus and the fusiform gyrus, areas that might be related to the affective appreciation stage in joke process. Unlike that of Coulson and Kutas (2001), the present study might support the hypothesis of a three stage model of humor processing (humor detection, resolution of incongruity and humor appreciation).  相似文献   
47.
双酚A (bisphenol, BPA)是一种广泛存在的环境内分泌干扰物,它可与雌激素受体结合干扰内源性雌激素对中枢神经系统的调控作用。本研究通过将10周龄小鼠灌胃染毒BPA (0.4、4、40 mg/kg/day)3个月,研究长期BPA暴露对成年小鼠记忆行为和突触可塑性的影响。开场行为测试结果表明, BPA (0.4、4、40 mg/kg/day)增加雄性的站立次数和理毛频率, BPA (4 mg/kg/day)却显著减少雌鼠的站立次数。水迷宫和被动回避行为模型检测显示, BPA主要损伤雄鼠的空间学习记忆和被动回避记忆。通过制备海马CA1区超薄切片后,电镜观测发现, BPA (0.4、40 mg/kg/day)暴露降低雄鼠海马CA1区突触数密度,缩短雄鼠突触前活性带长度,减小雄鼠突触后致密体(PSD)厚度,增加雄鼠突触间隙宽度。进一步用Western blot方法检测突触前、后的标志性蛋白Synapsin I和PSD95以及兴奋性氨基酸NMDA受体NR1亚基和AMPA受体GluR1亚基蛋白的表达,发现BPA暴露致雄鼠Synapsin I、PSD95、NR1蛋白表达水平下调。而BPA对雌鼠的记忆行为、突触形态、突触蛋白和受体蛋白均没有明显作用。以上结果提示长期B PA暴露性别特异性地影响成年小鼠的活动性和探究行为,损伤雄鼠的学习记忆,这些作用可能通过下调突触蛋白和NMDA受体的表达而负性影响突触结构可塑性,最终影响雄鼠的学习记忆功能。  相似文献   
48.
在押毒品犯人格的基本特征及其相关因素的研究   总被引:3,自引:0,他引:3  
本研究以 3 78名在押毒品犯为被试 ,以CPI为测量工具 ,探讨了在押毒品犯的基本特征和类型特征 ,并采用方差分析技术研究了影响毒品犯人格的若干因素。结果发现 ,与对照组相比 ,在押毒品犯除了在“自我控制”分量表上未发现显著差异外 ,其余的 1 9个分量表上均有显著差异 ;在押毒品犯在四种人格类型上的分布不平衡 ,主要集中在Delta类型 ;年龄、关押时间对毒品犯的人格特征的变异有一定影响 ,而减刑次数的影响不显著  相似文献   
49.
论心理学两种研究范式的整合趋向   总被引:14,自引:1,他引:13  
本文从方法学的视角分析了心理学研究的两大基本范式。文中讨论了量的研究与质的研究在本体论、认识论、价值论方面存在的差异,探讨了量的研究与质的研究整合的逻辑依据与历史依据。量的研究与质的研究存在各自的优缺点,它们的整合是必要的,也是可能的。文中进一步探讨了量的研究与质的研究整合的基本方式,包括次序式整合、平行式整合、交叉式整合等。  相似文献   
50.
父母教养态度与儿童在2-4岁期间的问题行   总被引:18,自引:1,他引:17  
考察父母的教养态度和儿童在2—4岁间的问题行为的发展变化。采用交叉时序滞后设计,对172名儿童从2岁起进行2年追踪,在被试2岁和4岁时,分别对他们的父母进行间卷调查。结果发现:儿童外显问题行为与父母教养态度的相互作用较强,儿童在2岁时的外显问题行为可以预测4岁时母亲的惩罚性,内隐问题行为与父母教养态度的相互作用较弱;从2岁到4岁之间,儿童外显问题行为具有较高的稳定性,内隐问题行为的稳定性相对略低,父母教养态度也都具有一定的稳定性。  相似文献   
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