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51.
Identification of distinct units within a continuous flow of human action is fundamental to action processing. Such segmentation may rest in part on statistical learning. In a series of four experiments, we examined what types of statistics people can use to segment a continuous stream involving many brief, goal-directed action elements. The results of Experiment 1 showed no evidence for sensitivity to conditional probability, whereas Experiment 2 displayed learning based on joint probability. In Experiment 3, we demonstrated that additional exposure to the input failed to engender sensitivity to conditional probability. However, the results of Experiment 4 showed that a subset of adults—namely, those more successful at identifying actions that had been seen more frequently than comparison sequences—were also successful at learning conditional-probability statistics. These experiments help to clarify the mechanisms subserving processing of intentional action, and they highlight important differences from, as well as similarities to, prior studies of statistical learning in other domains, including language.  相似文献   
52.
好朋友     
幼儿园,好朋友是在你只剩下黑蜡笔时将红蜡笔借给你用的人。一年级,好朋友是在你嬉玩遇到危险时与你牵手的人。二年级,好朋友是在你受人欺负时能帮助你的人。三年级,好朋友是在你没带午餐时能拿出自己的午餐与你分享的人。四年级,好朋友是在练习方形舞时愿意和你交换舞伴的人。……毕业时,好朋友是关在门里偷偷流泪而在向你祝贺时却能露出灿烂笑容的人。毕业后,好朋友是在你遇到烦恼时帮助你恢复好心情的人;是在你恋恋不舍泪眼模糊时能帮助你收拾上大学的行李并默默拥抱你的人;是让你相信你在这个世界上是被人爱着的人。长大了,好…  相似文献   
53.
54.
Objective: To observe the effect of Yangxueqingnao particles on rat vascular smooth muscle cell (VSMC) proliferation induced by lysophosphatidic acid (LPA). Methods: The amount of3H-TdR (3H-thymidine) admixed in cultured rat VSMC was measured and mitogen-activated protein kinase (MAPK) activity and lipid peroxidation end product malondialdehyde (MDA)content of the VSMC were assayed. Results: 1×10-9, 1×10-8, 1×10-7 mol/L LPA in a concentration dependent manner, induced the amount of 3H-TdR admixed, MAP kinase activity, and MDA content of the cultured rat VSMC to increase. However, 5%, 10%,and 15% Yangxueqingnao serum preincubation resulted in a decrease of 23.0%, 42.0%, and 52.0% (P<0.01) respectively in the amount of 3H-TdR admixed, a decline in VSMC MAP kinase activity of 13.9% (P<0.05), 29.6% (P<0.01), and 48.9% (P<0.01)respectively, and also, a decrease in MDA content of VSMC of 19.4%, 24.7%, and 43.2% (P<0.01) respectively, in the 1×10-7mol/L LPA-treated VSMC. Conclusions: LPA activates the proliferation and lipid peroxidation of VSMC in a concentration dependent manner. The LPA-induced VSMC proliferation is related to the activity of MAP kinases, enzymes involved in an intracellular signalling pathway. The results of the present study showed that Yangxueqingnao particles can effectively inhibit LPA-induced VSMC proliferation, MAP kinase activation, and reduce lipid peroxidative lesion.  相似文献   
55.
INTRODUCTIONRiceseedharborsadozenofplantpathogen icbacteria (Gotoetal.,1 988;Xieetal.,1 998) .Thebacterialpathogenscausearangeofricediseases,someverydestructivewhileothershavenoeffectonricecropgrowth .Inthisstudy ,wefoundalargenumberofbacteriaasso ciatedw…  相似文献   
56.
To obtain confirmation of the findings of the authors' earlier comparison of ever-pregnant and nonpregnant Black high school students from Tennessee, 16 students confirmed to be pregnant were substituted for the 33 subjects in the original study whose pregnancy status was based solely on self-report. The nonpregnant control group of 251 teens was utilized in both analyses. Although the confirmed pregnant group was too small to repeat the regression analysis, striking concordance of findings between the 2 studies emerged for all dependent variables except the Eysenck Personality Questionnaire anxiety scale. The lower anxiety scores recorded among subjects in the original study may be either a statistical artifact or a reflection of the fact that these pregnant teens remained in school while subjects in the second study were enrolled in programs centered around their pregnant status. Sexual activity scores were strong or moderate significantly more often in both groups of pregnant teens compared to their nonpregnant counterparts. Interesting was the finding that 81% of pregnant teens regarded romance novels and soap operas to be accurate portrayals of real-life dating relationships compared to only 49% of nonpregnant teens. On the other hand, only 56% of the pregnant subjects regarded their own relationships to have this romantic quality. In a future study, the role of such uncritical romantic ideals in adolescent pregnancy risk will be investigated in a larger sample.  相似文献   
57.
我们认为,普通教育亟待赋予新的必不可少的因素,需要使核心课程计划与学生的生活以及他们所继承中的世界的联系更加紧密协调。在学生们各自不同的兴趣之外,需要有某些共同的兴趣,有对知识更加综合化的观点和对生活更加深刻的理解。  相似文献   
58.
Caption rate and text reduction are factors that appear to affect the comprehension of captions by people who are deaf or hard of hearing. These 2 factors are confounded in everyday captioning; rate (in words per minute) is slowed by text reduction. In this study, caption rate and text reduction were manipulated independently in 2 experiments to assess any differential effects and possible benefits for comprehension by deaf and hard-of-hearing adults. Volunteers for the study included adults with a range of reading levels, self-reported hearing status, and different communication and language preferences. Results indicate that caption rate (at 130, 180, 230 words per minute) and text reduction (at 84%, 92%, and 100% original text) have different effects for different adult users, depending on hearing status, age, and reading level. In particular, reading level emerges as a dominant factor: more proficient readers show better comprehension than poor readers and are better able to benefit from caption rate and, to some extent, text reduction modifications.  相似文献   
59.
该文是美国的石油大王洛克菲勒写给儿子的一封信,在信中他告诫儿子:"如果你视工作为一种乐趣,人生就是天堂;如果你视工作为一种义务,人生就是地狱."这是积极的人生观,相信每个人看了都会从中受益  相似文献   
60.
箭与歌     
我向空中射出一枝箭,我不知它落在何方。因为它飞得如此神速,我的视力都追赶不上。我向高空唱出一支歌,我不知它落在何方。谁有如此犀利眼力,能追赶上歌声的飞扬?  相似文献   
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