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1.
牢记“两个务必”,加强大学生艰苦奋斗精神的教育   总被引:1,自引:0,他引:1  
艰苦奋斗是中华民族的传统美德,也是我们党在长期革命和建设中形成的优良传统和作风。针对目前相当一部分大学生艰苦奋斗观念淡薄这一现象,从引导大学生牢记“两个务必”的重要论述出发.就高校加强大学生艰苦奋斗精神教育的途径展开探讨。  相似文献   
2.
昆虫窝卵数:现象及其解释   总被引:3,自引:0,他引:3  
自然界广泛存在生物体产卵成批(窝、块等)现象(如姐妹利间异同、频次分布、季节动态及年间变异)等昆虫系统发育和个体生长(如解剖学特征、个体大小、年龄(产卵顺序)等内因和环境资源(寄主植物、昆虫、温度、水分等)等外因对窝卵数(clutchsize)均有一定影响,同一窝卵中的个体受捕食、被寄生、姐妹手足竞争、卵粒大小、个体大小、生殖力、性比等子代适合度因子也受窝卵数大小的影响,本文总结以上各现象提出一关系模型.以较为综合的“窝卵数与继续繁殖间的平衡”假说,从理论上阐述昆虫决定窝印数的机制,并讨论窝印数研究的实际意义。  相似文献   
3.
成功学诞生于美国,但中国成语中所蕴含的人生精神正可作出成功学的解释。拿破仑希尔所归纳的17条成功原则几乎对应于相关的中国成语。这种中西文化的对话和沟通,说明建立中国特色的成功学和成功人生评价体系不但具备丰厚的哲学储备,而且愈益时不我待,刻不容缓,尤其在中国加入WTO以后。  相似文献   
4.
Predictivism is the view that successful predictions of “novel” evidence carry more confirmational weight than accommodations of already known evidence. Novelty, in this context, has traditionally been conceived of as temporal novelty. However temporal predictivism has been criticized for lacking a rationale: why should the time order of theory and evidence matter? Instead, it has been proposed, novelty should be construed in terms of use-novelty, according to which evidence is novel if it was not used in the construction of a theory. Only if evidence is use-novel can it fully support the theory entailing it. As I point out in this paper, the writings of the most influential proponent of use-novelty contain a weaker and a stronger version of use-novelty. However both versions, I argue, are problematic. With regard to the appraisal of Mendeleev’ periodic table, the most contentious historical case in the predictivism debate, I argue that temporal predictivism is indeed supported, although in ways not previously appreciated. On the basis of this case, I argue for a form of so-called symptomatic predictivism according to which temporally novel predictions carry more confirmational weight only insofar as they reveal the theory’s presumed coherence of facts as real.  相似文献   
5.
The aim of this paper is to put in place some cornerstones in the foundations for an objective theory of confirmation by considering lessons from the failures of predictivism. Discussion begins with a widely accepted challenge, to find out what is needed in addition to the right kind of inferential–semantical relations between hypothesis and evidence to have a complete account of confirmation, one that gives a definitive answer to the question whether hypotheses branded as “post hoc monsters” can be confirmed. The predictivist view is then presented as a way to meet this challenge. Particular attention is paid to Worrall’s version of predictivism, as it appears to be the most sophisticated of the lot. It is argued that, despite its faults, his view turns our heads in the right direction by attempting to remove contingent considerations from confirmational matters. The demand to remove such considerations becomes the first of four cornerstones. Each cornerstone is put in place with the aim to steer clear of the sort of failures that plague various kinds of predictivism. In the process, it becomes obvious that the original challenge is wrongheaded and in need of revision. The paper ends with just such a revision.  相似文献   
6.
《Journal of Natural History》2012,46(23-24):1427-1443
This paper provides the first results of pollinator fauna associated to the reproductive biology of Antirrhinum charidemi, Antirrhinum graniticum and Antirrhinum braun-blanquetii. Censuses of over 16 hours spanning the flowering phenology of each species were drawn up. As previously hypothesized, the characteristic occluded (personate) corolla of Antirrhinum was exclusively pollinated by bees, but by a higher number (four) of bee families than predicted. Seven bee species (Bombus hortorum, Anthidium manicatum, Chalicodoma lefebvrei, Anthidium sticticum, Anthophora dispar, Xylocopa violacea and Anthidium cingulatum) account for over 90% of flower visits (2098). The flower visitation index varied between species (0.0126?0.0320), reaching relatively medium values compared to Mediterranean plants. In contrast, reproductive success was found to be high when estimated as both fruit (45.4–84.2%) and seed (75.4–98.4%) sets, suggesting that these bee guilds are effective pollinators of the three self-incompatible Antirrhinum species. Specialization of the personate flower of Antirrhinum is therefore interpreted for bees with both large bodies and high visitation indices.  相似文献   
7.
本文运用观察法、访谈法、问卷法,对云南省怒江区泸水县直过民族这个特殊群体的受教育现状及学习动机进行了深入调查和研究.结果表明,语言障碍、自然条件恶劣、基础建设不完备,是直过民族经济文化发展滞后的主要原因.最后提出实施"双轨制"办学法,以激发人们的求学动力,从而培养适合该地区的人才。  相似文献   
8.
自古以来,“小道观”制约着小说创作和小说理论的发展。直到近代,梁启超提出“小说为文学之最上乘”的理论思想,小说的地位才得以提高。然而这一著名论题,亦有偏颇不足之处。  相似文献   
9.
10.
The Lined Seedeater (Sporophila lineola) is a migratory species that inhabits a variety of open habitats in South America. We studied the breeding biology and territorial behaviour of a colour-banded population of the species in the Universidade Federal de Viçosa, Campus Florestal (1–19,8808ºS, –44,4136ºW), during two breeding seasons (2014/2015 and 2015/2016), which spans from December to April. We monitored 74 nests of this species. The nest is a low cup supported between a fork. Nests are mainly built with grass stems and rootlets, with spider-web used to hold the material together and to bind the nest to its supporting plant. Females are solely responsible for nest building and incubation, which is synchronic, and also for feeding nestlings to a large extent. Males are responsible for defending the territory, which corresponds to a small portion of the home range restricted to the nest environs, and also feed the nestlings. Mean clutch size is two eggs (78% of nests monitored), with clutches of three (20.3%) and four (1.7%) eggs also observed. Eggs are whitish, covered with dark brown blotches and spots to a variable extent. Mean incubation period, considered as the period between the onset of incubation and hatching of the first egg, is 11 days. Nestling period, considered as the period between hatching of the first egg and fledging of the last young, is 10 days. During the first breeding season, the simple percentage of successful nests was 34.1%, while the Mayfield success was 29.8%, with slightly higher values observed during the second breeding season, with 39.4% and 35.7%, respectively. We recorded, for the first time, three cases of polygamy in the species. We also recorded breeding site fidelity for the first time in the species, with males returning to the same territory owned in a previous breeding season.  相似文献   
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