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31.
Kathy Darragh Gabriela Montejo‐Kovacevich Krzysztof M. Kozak Colin R. Morrison Clarisse M. E. Figueiredo Jonathan S. Ready Camilo Salazar Mauricio Linares Kelsey J. R. P. Byers Richard M. Merrill W. Owen McMillan Stefan Schulz Chris D. Jiggins 《Ecology and evolution》2020,10(9):3895-3918
In many animals, mate choice is important for the maintenance of reproductive isolation between species. Traits important for mate choice and behavioral isolation are predicted to be under strong stabilizing selection within species; however, such traits can also exhibit variation at the population level driven by neutral and adaptive evolutionary processes. Here, we describe patterns of divergence among androconial and genital chemical profiles at inter‐ and intraspecific levels in mimetic Heliconius butterflies. Most variation in chemical bouquets was found between species, but there were also quantitative differences at the population level. We found a strong correlation between interspecific chemical and genetic divergence, but this correlation varied in intraspecific comparisons. We identified “indicator” compounds characteristic of particular species that included compounds already known to elicit a behavioral response, suggesting an approach for identification of candidate compounds for future behavioral studies in novel systems. Overall, the strong signal of species identity suggests a role for these compounds in species recognition, but with additional potentially neutral variation at the population level. 相似文献
32.
33.
Dieter Gross 《Phytochemistry》1975,14(10):2105-2112
34.
Gabrielle Thiébaut Guillaume Tixier François Guérold Serge Muller 《Hydrobiologia》2006,570(1):159-164
The aim of our study was to assess the water quality of the upper Moselle river by using biological indices. Simultaneous
physico-chemical surveys were also undertaken from May 1999 to April 2000. Twelve sampling sites were selected in order to
provide a wide range of potential pollution. Chemical analysis did not reveal any major problem of pollution. However a lower
water quality resulting from domestic pollution was established for some sampling sites. A biological monitoring combining
both macroinvertebrates and macrophytes was performed. Biological indices based on plant community structure and macrophyte
composition were not pertinent tools, whereas simple indices based on taxonomic richness of particular groups of macroinvertebrates
were strongly correlated with several chemical parameters, showing that such simple biological variables should represent
powerful indicators of ecosystem degradation. 相似文献
35.
朝鲜毛球蚧蜡泌物的超微形态与红外光谱特征 总被引:4,自引:3,他引:4
采用扫描电镜和红外光谱技术研究了朝鲜毛球蚧Didesmococcus koreanus在不同发育阶段蜡泌物的超微形态和化学成分。结果发现:该虫在低龄期的蜡泌物的形态是长丝状,到3龄和成虫期是由湿蜡凝结成不同大小的颗粒,块状和片状。雄虫蜡壳是薄蜡片构成,表面呈鱼鳞状凹凸。低龄期若虫蜡泌物的红外光谱特征与雌成虫的十分相似,说明二者所含的主要化学成分是相同的,雄虫和低龄若虫及雌成虫蜡壳萃取物的红外光谱的吸收峰型基本一致,但在1 240.7 cm-1处出现一个中等强度的特征峰,这充分说明3种蜡泌物的有机化合物种类和结构一致,只是雄虫分泌物与另二者比较具有特征官能团,从而,利用该吸收峰可以区别出雄虫。此外,根据红外光谱特征分析,可以知道该虫蜡泌物的化学成分主要为长链脂肪酸、脂肪醇和一些带芳香环的化合物。 相似文献
36.
Vascular structures in natural systems are able to provide high mass transport through high surface areas and optimized structure. Few synthetic material fabrication techniques are able to mimic the complexity of these structures while maintaining scalability. The Vaporization of a Sacrificial Component (VaSC) process is able to do so. This process uses sacrificial fibers as a template to form hollow, cylindrical microchannels embedded within a matrix. Tin (II) oxalate (SnOx) is embedded within poly(lactic) acid (PLA) fibers which facilitates the use of this process. The SnOx catalyzes the depolymerization of the PLA fibers at lower temperatures. The lactic acid monomers are gaseous at these temperatures and can be removed from the embedded matrix at temperatures that do not damage the matrix. Here we show a method for aligning these fibers using micromachined plates and a tensioning device to create complex patterns of three-dimensionally arrayed microchannels. The process allows the exploration of virtually any arrangement of fiber topologies and structures. 相似文献
37.
Anthocyanin pigments in Callistephus chinensis 总被引:1,自引:0,他引:1
Gert Forkmann 《Phytochemistry》1977,16(2):299-301
Identification of the anthocyanin pigments in the flowers of six genotypes of Callistephus chinensis has confirmed that a series of multiple alleles, R, r′ and r are responsible for the production of delphinidin, cyanidin, and pelargonidin derivatives respectively. However, mixtures of anthocyanidin types were present in all genotypes. In the presence of gene M, mainly 3,5-diglycosides were found; in recessive genotypes (mm) there were only 3-mono-glucosides. Unstable acylated derivatives of these pigments were also present. 相似文献
38.
39.
镰叶西番莲的化学成分 总被引:4,自引:0,他引:4
从镰叶西番莲(Passiflora wilsonii)的腾茎中分离到6个化合物,经理化性质和波谱分析,分别确定为:glut-5-en-3β-ol(I)、maslinic acid(Ⅱ),friedelin(Ⅲ),ergosterol epidioxide(Ⅴ)和β-谷甾醇(Ⅳ)。以上化合物均为首次从镰叶西番莲的腾茎中分离得到。 相似文献
40.
采用正反相硅胶、Sephadex LH-20凝胶、MCI树脂等层析技术从中药益智95%乙醇提取物的乙酸乙酯部位分离得到13个化合物,运用现代波谱技术分别鉴定为:益智酮甲(1,yakuchinone A)、益智醇(2,oxyphyllacin-ol)、白杨素(3,chrysin)、rhamnocitrin(4)、oxyphyllenodiol A(5)、oxyphyllenodiol B(6)、nootkatone(7)、dehydro-noot-katone(8)、7-epi-teucrenone(9)、oxyphyllenone A(10)、oxyphyllenone B(11)、原儿茶酸(12,protocatechuic acid)和琥珀酸(13,succinic acid)。其中化合物4、13为首次从该植物中分得,化合物8为新的天然产物。 相似文献