白腹锦鸡繁殖生态观察

报道了白腹锦鸡Chrysolophus amherstiae在滇中高原地区的典型栖息地、繁殖期的种群密度、占区行为、求偶炫耀、巢与卵的特征、雌鸟孵卵行为及雏鸟的食性。图2表4参8

蓝氏贾第虫核被膜缺口的电镜观察

以蓝氏贾第虫作为双滴虫类的代表, 是迄今所知的现存最原始的真核生物类群。对其细胞核进行了电镜观察。除未见核仁外, 还发现其核被膜的横切面上存在有缺口, 在缺口的边缘处, 核内膜与核外膜是相互连接的。核被膜缺口处常有一核纤层样的薄层分隔核质与细胞质。核被膜缺口的发现证实了李靖炎(1979)的核被膜起源假说的推断。

RESTRICTION-ENDONUCLEASE ANALYSIS OF MITOCHONDRIAL-DNA OF MUNTJACS AND RELATED DEER

Twelve restriction endonucleases were employed to analyze the mitochondrial DNA of four species of muntjacs and two related species of deer: red muntjac (M. muntjak), Gongshan muntjac (M. gongshanensis), black muntjac (M. crinifrons), Chinese muntjac (M. reevesi), tufted deer (Elaphodus cephalophus), and forest musk deer (Moschus berezovskii). A total of 170 restriction fragments were detected among the samples. Fragments data were used to calculate the genetic distance (i.e. percent sequence divergency) among species, which in turn were used to construct a phylogenetic tree and to estimate divergency times. Our analysis indicates that the black muntjac and the Gongshan muntjac are most closely related, and that they are closely realted to the red muntjac and the Chinese muntjac. Additionally, the tufted deer is genetically closer to muntjacs than the musk deer is.

The shear mode of multilayer graphene

The quest for materials capable of realizing the next generation of electronic and photonic devices continues to fuel research on the electronic, optical and vibrational properties of graphene. Few-layer graphene (FLG) flakes with less than ten layers each show a distinctive band structure. Thus, there is an increasing interest in the physics and applications of FLGs. Raman spectroscopy is one of the most useful and versatile tools to probe graphene samples. Here, we uncover the interlayer shear mode of FLGs, ranging from bilayer graphene (BLG) to bulk graphite, and suggest that the corresponding Raman peak measures the interlayer coupling. This peak scales from ∼43cm -1 in bulk graphite to ∼31cm -1 in BLG. Its low energy makes it sensitive to near-Dirac point quasiparticles. Similar shear modes are expected in all layered materials, providing a direct probe of interlayer interactions. © 2012 Macmillan Publishers Limited. All rights reserved.