中教数据库 > 昆虫科学:英文版 > 文章详情

Methoprene does not affect juvenile hormone titers in honey bee (Apis mellifera) workers



0 共6页 免费 中文科技期刊数据库

How many words does a learner become fluent in English as a foreign language

【摘要】语言学习者用外语听读时,习得的词汇量越多,文章的理解力就越强。同样,语言学习者掌握的单词越多,他们就越能很好地在说写中表达 自己。

《山西青年》 | 2017年10期 | 曹青青

0 42 2 免费 收藏

Food restriction affects maternal investment but not neonate phenotypes in a viviparous lizard

【摘要】Food availability significantly affects an animal’s energy metabolism, and thus its phenotype, survival, and reproduction. Maternal and offspring responses to food conditions are critical for understanding population dynamics and life-history evolution of a species. In this study, we conducted food manipulation experiments in field enclosures to identify the effect of food restriction on female reproductive traits and postpartum body condition, as well as on hatchling phenotypes, in a lacertid viviparous lizard from the Inner Mongolian desert steppe of China. Females under low-food availability treatment (LFT) had poorer immune function and body condition compared with those under high-food availability treatment (HFT). The food availability treatments significantly affected the litter size and litter mass of the females, but not their gestation period in captivity or brood success, or the body size, sprint speed, and sex ratio of the neonates. Females from the LFT group had smaller litter sizes and, therefore, lower litter mass than those from the HFT group. These results suggest that female racerunners facing food restriction lay fewer offspring with unchanged body size and locomotor performance, and incur a cost in the form of poor postpartum body condition and immune function. The flexibility of maternal responses to variable food availability represents an important life strategy that could enhance the resistance of lizards to unpredictable environmental change.

《动物学研究》 | 2017年2期 | Yang Wang

0 2 免费 收藏

How Language Barriers Affect Cross-border Trade

【摘要】<p>The issue of language barriers on cross-border trade really exists in many countries. But how do they affect it? Firstly, language</p><p>barriers present great obstacles to the communications of cross-border trade. Secondly, not only do language barriers cause some losses</p><p>to companies, but they also cause some unknown expectation, misunderstanding and great obstacles in trading. Therefore, it is urgent to</p><p>eliminate obstacles of language on cross-border trade.</p><p><br/></p>

《环球市场信息导报》 | 2017年17期 | 杨秀兰

0 67 2 免费 收藏

Farewell, But Not Goodbye

【摘要】<p>Only destiny can explain the encounter and magic chemistry</p><p>between Chen Yuejin, an octogenarian living in the small town of</p><p>Wuyi in China’s Jinhua District and Shimizu Mamiko, currently in</p><p>her third year at Waseda University, one of the most prestigious academic</p><p>“holy lands” in Japan.</p><p><br/></p>

《文化交流》 | 2016年10期 | By Li Yan

0 48 2 免费 收藏

ZIKA-How fast does this virus mutate?

【摘要】<p>The World Health Organization has declared the<br/>present Zika virus epidemic to be a ‘Public Health<br/>Emergency of International Concern’. The virus<br/>appears to have spread from Thailand to French<br/>Polynesia in 2013, and has since infected over a<br/>million people in the countries of South and Central<br/>America. In most cases the infection is mild and<br/>transient, but the virus does appear to be strongly<br/>neurotropic and the presumptive cause of both birth<br/>defects in fetuses and Guillain-Barré syndrome in<br/>some adults. In this paper, the techniques and<br/>utilities developed in the study of mitochondrial DNA<br/>were applied to the Zika virus. As a result, it is<br/>possible to show in a simple manner how a<br/>phylogenetic tree may be constructed and how the<br/>mutation rate of the virus can be measured. The study<br/>showed the mutation rate to vary between 12 and 25<br/>bases a year, in a viral genome of 10 272 bases. This<br/>rapid mutation rate will enable the geographic<br/>spread of the epidemic to be monitored easily and<br/>may also prove useful in assisting the identification<br/>of preventative measures that are working, and<br/>those that are not.</p>

《动物学研究》 | 2016年2期 | Ian S. LOGAN

0 83 2 免费 收藏

Micro Carving: Not a Small World

【摘要】<p>The art of micro-carving refers generally to the engraving</p><p>of infinitesimal characters on ivory or human hair. It</p><p>takes an all-rounder artist to excel in the field, as can be</p><p>seen in the artistry of Li Hao, chair of Zhejiang Microscopic</p><p>Carving Academy.</p><p><br/></p>

《文化交流》 | 2016年12期 | Xu Jihong

0 64 2 免费 收藏

Does mRNA structure contain genetic information for regulating co-translational protein folding?

【摘要】<p>Currently many facets of genetic information are illdefined.</p><p>In particular, how protein folding is</p><p>genetically regulated has been a long-standing issue</p><p>for genetics and protein biology. And a generic</p><p>mechanistic model with supports of genomic data is</p><p>still lacking. Recent technological advances have</p><p>enabled much needed genome-wide experiments.</p><p>While focusing on the effect of codon optimality,</p><p>these studies have supplied mounting evidence</p><p>suggesting a role of mRNA structure in the</p><p>regulation of protein folding by modulating</p><p>translational elongation rate. In conjunctions with</p><p>previous theories, this mechanistic model of protein</p><p>folding guided by mRNA structure shall expand our</p><p>understandings of genetic information and offer new</p><p>insights into various biomedical puzzles.</p><p><br/></p>

《动物学研究》 | 2017年1期 | Jian-Rong Yang

1 1 2 免费 收藏

基于Zig Bee技术的企业照明控制系统研究

【摘要】首先对当前企业的照明控制系统的现状进行分析,基于现状以及存在的不足,提出利用Zig Bee技术对企业办公照明 的控制系统进行改进,达到对企业办公照明节能、环保的目标。

《科技风》 | 2018年15期 | 陈雪军

0 34 2 免费 收藏


Copyright © 2013-2016 ZJHJ Corporation,All Rights Reserved


京公网安备 11011102000866号