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1.
Ultrasonic wave testing was applied to investigate the quality and weathering status of rock specimens obtained in two borings
situated in the Xishan Buddha rock slope in Taiyuan, China. This paper pays special attention to the distribution of bulk
density, dynamic parameters and static parameters of rock specimens as well as the relationship between static and dynamic
parameters. The results illustrate that the distribution of both parameters is identical along the depth of two drilled holes
in the rock slope. When the hole depth increases, the density of rock mass, saturated compression strength and static elastic
modulus, dynamic elastic modulus and wave velocity also show increase tendency. The weathering degree in the rock mass ranging
from the surface of cliff to the depth of 2.5 m is the highest while the rock mass is unsalted and more rigid when the depth
is larger than 3.0 m. The relationship between dynamic elastic modulus, sonic wave velocity and horizontal depth indicates
that dynamic elastic modulus is more sensitive than sonic wave velocity. Conversely, by comparing quantity relationship between
static elastic modulus and sonic wave velocity, it is found that the composition of rock has a great influence on the relationship
between static and dynamic parameters, that is, inequality of rock composition will lead to dispersion and abnormality of
the distribution of static and dynamic parameters. 相似文献
2.
An established, captive colony of 74 rhesus monkeys (Macaca mulatta) was group-tested on a simultaneous visual discrimination problem and three reversals of the initial discrimination. The task incorporated important aspects of rhesus foraging behavior. Although other studies of communal groups of nonhuman primates have reported rapid learning, subjects in the present study showed no evidence of one-trial acquisition of the initial problem or of rapid learning-set formation across the reversal series. Instead, mean and individual performance, on all variables measured, improved gradually, both within and across series. Subjects appeared to “learn how to learn,” consistent with findings of traditional studies of individual discrimination learning. Our finding of gradual learning in group-living animals argues that the source of rapid learning in previous reports is not attributable to social influence or ecological relevance, but may reflect specific procedural or species differences between studies. 相似文献
3.
甘肃作家雪漠的长篇小说《猎原》是新世纪初期比较有代表性的一部生态文学文本。在这部作品里,雪漠以现实主义的手法再现了当代中国西部农民在日益恶化的自然生态环境和社会生态下卑微而又坚韧活着的生存境况及他们在日常生活中所显示出的精神文化生态,全面展现了西部农民与自然生态之间的紧张关系,并且深入反思和探究了西部农民的精神文化生态和不公正不合理的社会生态之间的隐秘关系。 相似文献
4.
R. Yorke Edwards 《The Journal of environmental education》2013,44(1):17-18
Abstract The ecological worldviews of 95 undergraduates were assessed via Blaikie's Ecological World View scale (1992). Positive ecological worldviews were associated with receptivity to arguments for preserving endangered species based on ethics and morality, the importance of a species to the ecosystem, and one's ability to make a difference; the type of organism that was endangered was not a factor in determining the effectiveness of a message. There was no relationship between ecological worldviews and receptivity to arguments on the basis of aesthetics or economics. Women had more positive ecological worldviews and found moral arguments to be more persuasive than did men. 相似文献
5.
感染伊氏锥虫(10~5/只)后24小时的NIH小鼠,用不同浓度的DL—a—二氟甲基鸟氨酸(DFMO)水溶液饲喂治疗,连续3天,结果表明,以1％,2％和4％DFMO治疗的小鼠,疗后30天未见虫血症,用其血液及脑组织感染健康的NIH小鼠,也没有出现虫血症,治愈率均达100％。实验证明:DFMO是一种很有发展前途的新型抗锥虫药。 相似文献
6.
Narr RF 《Journal of deaf studies and deaf education》2008,13(3):405-416
Visual phonics, a system of 45 hand and symbol cues that represent the phonemes of spoken English, has been used as a tool in literacy instruction with deaf/hard-of-hearing (DHH) students for over 20 years. Despite years of anecdotal support, there is relatively little published evidence of its impact on reading achievement. This study was designed to examine the relationship between performance on a phonological awareness task, performance on a decoding task, reading ability, and length of time in literacy instruction with visual phonics for 10 DHH kindergarten through Grade 3 students receiving academic instruction with sign-supported English and American Sign Language. Findings indicate that these students were able to use phonological information to make rhyme judgments and to decode; however, no relationship between performance on reading ability and length of time in literacy instruction with visual phonics was found. 相似文献
7.
通过研究棕色田鼠（Microtus mandarinus）在同性及异性尿液气味源刺激下的行为及尿标记数量差异,探讨了棕色田鼠尿液在个体性别识别中的作用．结果表明：棕色田鼠能够通过尿液进行性别辨识,雌雄棕色田鼠通过尿液进行性别识别中存在性二型． 相似文献
8.
Infants require locomotor experience to behave adaptively at a drop‐off. However, different experimental paradigms (visual cliff and actual gaps and slopes) have generated conflicting findings regarding what infants learn and the specificity of their learning. An actual, adjustable drop‐off apparatus was used to investigate whether learning to distinguish a step from a cliff transfers from crawling to walking. Experienced 12‐month‐old crawlers (n = 16) refused to crawl over risky drop‐offs but novice 12‐month‐old walkers (n = 17) stepped repeatedly over the edge. Experienced 18‐month‐old walkers (n = 18) refused to walk over risky drop‐offs but descended using alternative methods. These findings suggest that infants do not acquire generalized responses like fear or wariness of heights. Rather, infants learn to perceive affordances for the experienced action. 相似文献
9.
Acquisition, extinction, and transfer of facilitation were explored in a series of experiments with C57BL/6J mice. With a
procedure in which an auditory target was followed by food only in the presence of a visual facilitator, Experiments 1—4 showed
that the facilitator promoted magazine entries to the auditory target. This enhancement effect was eliminated by training
the facilitator as a conditioned inhibitor (Experiments 1 and 3B). Enhancement was also reduced by nonreinforced presentations
of the facilitator in a discrimination procedure (Experiment 1) and by simple nonreinforcement of the facilitator (Experiments
2, 3A, and 4). In contrast to the results obtained with a facilitator, simple nonreinforcement of an inhibitor, a visual cue
that had signaled when an auditory target would not be reinforced, did not reduce its ability to modulate responding to that
target (Experiment 4). However, both the facilitator and the inhibitor were found to transfer their modulatory effects to
other targets (Experiment 4). Finally, mice demonstrated no evidence of differential responding on a biconditional discrimination
procedure in which one auditory target (A1) was reinforced in the presence of one visual stimulus (L1) but not in the presence
of another (L2), and a different auditory target (A2) was reinforced in L2 but not in L1 (Experiment 5). The implications
of these results for analysis of the function of a facilitator are discussed. 相似文献
10.
Two rhesus monkeys were tested in 6- and 10-item list memory tasks for performance changes as a function of the exposure duration of the list stimuli and the interstimulus interval (ISI) between successive list stimuli. Accuracy increased with longer item exposure duration and tended to decrease with longer ISI duration. Humans, by contrast, typically show increases in accuracy with ISI, a result taken as evidence of rehearsal. The decrease in accuracy for monkeys suggests that they were not using rehearsal processes in these list memory experiments. Further tests in which choice accuracy with predictable ISIs was compared with choice accuracy with unpredictable ISIs also yielded no evidence of rehearsal by the monkeys. This apparent absence of rehearsal mechanisms in monkeys, in situations also shown to support human rehearsal, is discussed as a potential difference in the visual working memory processes of the two species. 相似文献
11.
Although recent studies have convincingly demonstrated that emotional expressions can be judged reliably from actor-posed facial displays, there exists little evidence that facial expressions in lifelike settings are similar to actor-posed displays, are reliable across situations designed to elicit the same emotion, or provide sufficient information to mediate consistent emotion judgments by raters. The present study therefore investigated these issues as they related to the emotions of happiness, surprise, and fear. 27 infants between 10 and 12 months of age (when emotion masking is not likely to confound results) were tested in 2 situations designed to elicit hapiness (peek-a-boo game and a collapsing toy), 2 to elicit surprise (a toy-switch and a vanishing-object task), and 2 to elicit fear (the visual cliff and the approach of a stranger. Dependent variables included changes in 28 facial response components taken from previous work using actor poses, as well as judgments of the presence of 6 discrete emotions. In addition, instrumental behaviors were used to verify with other than facial expression responses whether the predicted emotion was elicited. In contrast to previous conclusions on the subject, we found that judges were able to make all facial expression judgments reliably, even in the absence of contextual information. Support was also obtained for at least some degree of specificity of facial component response patterns, especially for happiness and surprise. Emotion judgments by raters were found to be a function of the presence of discrete facial components predicted to be linked to those emotions. Finally, almost all situations elicited blends, rather than discrete emotions. 相似文献
12.
敦煌莫高窟崖体顶部及陡坎地带表层松散的风化堆积物,在大风条件下极易发生滚石和流砂,威胁着游人和洞窟的安全.针对以往的加固保护措施,本研究提出了PS花管注浆加固新工艺,即利用打入风化堆积层的花管将PS浆液引入一定的深度固化,形成固化柱,再对表面喷洒PS,使注浆形成的固化柱与表面加固层连成一体.现场试验表明,除花管管径外,PS溶液浓度、堆积物组分以及含水量均对PS固化半径产生重要的影响.固化半径随着PS溶液浓度增大而减小,但是在较低含水量情况下,固化半径却随着堆积物中细颗粒含量的增大而显著增大.声波测试结果表明,经过PS固化后,地层波速增大20～70%,形成的固化体强度明显增大.试验证明,PS花管注浆形成的固化柱能将表面防风化加固层连成一体,将会提高莫高窟强风化地层的加固效果. 相似文献
13.
The Structure of Temperamental Fear and Pleasure in Infants: A Psychometric Perspective 总被引：2，自引：0，他引：2
Despite the prominence of temperament constructs in the study of infant development, little evidence exists about the internal structure of temperament. We assessed temperament both via questionnaire and in repeated laboratory visits for 168 9-month-old twins and singletons. Mothers' and fathers' agreement on temperament questionnaire scales was low, except for scales tapping negative emotionality and activity level. The factor structure of mothers' and fathers' questionnaire scales also differed, with fathers tending to associate higher motoric activity with hedonically positive behaviors. We measured fearfulness during 2 visual cliff episodes and a stranger approach, and we measured joy/pleasure during a series of 4 games. For both fearfulness and pleasure we found moderate cross-situation generality, short-term stability, and convergence with specific temperament questionnaire scales. Parameters of response, such as latency, duration, and intensity, intercorrelated within--but not across--response types. Fearful distress and avoidance proved to be uncorrelated. The results suggest that the component behaviors of infant fearfulness and pleasure are structured in a fashion consistent with a temperamental interpretation. 相似文献
14.
The aims of this research were to investigate the ways in which students in primary and secondary schools process texts and accompanying visual aids and to ascertain any developmental patterns. Think-aloud protocols were gathered from 119 Grade 5, Grade 7 and Grade 9 students while they read and studied grade-appropriate History and Science materials which contained both text and visual aids (tables, diagrams). Analyses of the think-aloud protocols yielded over 50 different processes, subsumed under 10 major categories. While the History results showed no reliable grade differences in the 10 think-aloud categories, the Science results showed developmental differences. Older students demonstrated a more diverse array of strategies, and explicit linking of text and visual aid information was not as evident in the younger students. ANOVAs following cluster analyses showed weak relationships between cluster membership and outcomes. Implications for instruction are discussed. 相似文献
15.
赫胥黎对生物进化论作出划时代创新。他汲取古希腊赫拉克利特的直观辩证法,使康德宇宙整体发展观推陈出新。从人类发生学和人猿比较解剖学新视角,重新确定了人在生物界中的位置,使达尔文的人猿同祖论,从"假说"深化为科学的结论。他看到人类社会和生物进化的差别,纠正了社会达尔文主义的错误。他把猿与具有"至善伦理"的人和生物进化相统一,赋予人类保护生态系统义不容辞的社会责任。他由此成为生态伦理学说的开拓者。 相似文献
16.
花山岩画文化地位刍议 总被引：1，自引：0，他引：1
吴能贞 《南宁师范高等专科学校学报》2010,27(1):10-15
花山岩画是世界岩画的极品,花山文化是壮民族文化形成的标志,是中国岭南土著文化的缩影,是连接中国—东盟的文化桥梁。政府和学术界对花山岩画文化地位的关注和研究,可以为花山＂申遗＂营造学术氛围。 相似文献
17.
方法：观察了老年小鼠服旱莲草水煎剂后,脾淋巴细胞IL2、MAF的分泌和DNA合成的变化;并观察了旱莲草体外对脾淋巴细胞DNA合成的影响．结果：①使老年小鼠脾淋巴细胞分泌IL2逐渐减少（P＜0.001）,并呈剂量依赖关系（r=-8988）;②体内外实验表明高浓度旱莲草水煎剂抑制脾淋巴细胞在ConA激活后的DNA合成,但无ConA时DNA合成不受影响;③老年小鼠脾淋巴细胞分泌MAF能力明显低于青年小鼠（P＜0.05）,灌服旱莲草24g/kg×7d使老年小鼠脾淋巴细胞分泌MAF能力明显增强（P＜0.05）． 相似文献
18.
12-month-old infants were familiarized either tactually or visually with objects and then tested for visual recognition memory using either (1) the familiar and a novel object, (2) colored pictures of the objects, or (3) outline drawings of them. In Study 1, infants showed recognition memory on all 3 visual intramodal problems but showed cross-modal transfer only when objects were used as test stimuli. With increased familiarization times in Study 2, transfer from tactually presented samples to both pictorial displays was achieved, indicating that after feeling an object the infants were able to recognize it visually solely on the basis of its contour. With reduced familiarization times in Study 3, there was no evidence for transfer from visually presented samples to the 2 pictorial displays, replicating the pattern of results observed cross-modally in Study 1 and suggesting that, at least in certain respects, cross-modal and intramodal perception follow similar principles. 相似文献
19.
王真 《山西大学师范学院学报》2009,(4):29-31
生态文明观的核心是＂人与自然协调发展＂。建构＂生态文明＂需要克服三种错误思维方法：传统的＂主客二分＂法、还原论的方法、线性的方法。建构生态文明的科学方法是：对象化的方法、系统论的方法、非线性的方法。方法论视角的转变,对解决人与自然的关系危机具有重要的意义。 相似文献
20.
武夷山兰属植物资源初步调查 总被引：1，自引：0，他引：1
经初步统计,武夷山有野生兰属植物10种,以地生兰为主,约7种,附生半附生兰3种,大约占兰科植物种的12．82％。介绍武夷山野生兰属植物资源的地理分布情况、生态特点和生长习性,提出保护和开发野生兰花资源的建议。 相似文献