我国新蚤属斯氏组(stevensi group of Neopsylla)的分类研究及新种新亚种记述(Siphonaptera:Hystrichopsyllidae)

我国的新蚤属已知有18个种和亚种,其中有12种和亚种属于多毛组,6种属于斯氏组。著者等今整理了从云南、贵州、福建和陕西四省所得到的斯氏组新蚤,除尊新蚤和异种新蚤未获得以外共记述了10种和亚种。其中无规新蚤和福建新蚤为已知种,不同新蚤为我国新记录,均作了补充记述。另外还发现了斯氏新蚤的雌性。本种系Rothschild 氏于1915年根据采自尼泊尔-锡金边境的一只雄蚤而记述。至1932年Jordan氏根据从四川得到的标本记述了雌性形态。本文根据从云南获得的雌雄性标本,重新记述了雌性形态,并由于早先文献中证据的不足和结论的可疑提出Jordan氏1932年记述的雌蚤并非本种,可能是其他种新蚤的雌性。 本文记述了两个斯氏组的新种:1)相关新蚤新种,采自云南中甸 Apodemus agrarius;2)二毫新蚤新种,采自云南中甸 A.agrarius(?E.proditor)。另外,对特新蚤进行了种下分类,提出特新蚤乃一多型物种,根据其种群特征将所得标本分别订为三个地理亚种:(1)云南大理的为特特新蚤;贵阳的为贵阳特新蚤;福建的为闽北特新蚤。 最后编制了我国斯氏组新蚤12个种和亚种的分类检索表。     

The lepidopteran mitochondrial control region: structure and evolution

For several species of lepidoptera, most of the approximately 350-bp mitochondrial control-region sequences were determined. Six of these species are in one genus, Jalmenus; are closely related; and are believed to have undergone recent rapid speciation. Recent speciation was supported by the observation of low interspecific sequence divergence. Thus, no useful phylogeny could be constructed for the genus. Despite a surprising conservation of control-region length, there was little conservation of primary sequences either among the three lepidopteran genera or between lepidoptera and Drosophila. Analysis of secondary structure indicated only one possible feature in common--inferred stem loops with higher-than-random folding energies-- although the positions of the structures in different species were unrelated to regions of primary sequence similarity. We suggest that the conserved, short length of control regions is related to the observed lack of heteroplasmy in lepidopteran mitochondrial genomes. In addition, determination of flanking sequences for one Jalmenus species indicated (i) only weak support for the available model of insect 12S rRNA structure and (ii) that tRNA translocation is a frequent event in the evolution of insect mitochondrial genomes.      

继新蚤属三新种记述及对属征的进一步探讨

继新蚤属(Genoncopsylla Wu,Liu,1966)是根据我国西藏所采得的长鬃继新蚤(C.longise-gosa Wu,Wu ＆ Liu,1966)于1966年建立的一个新属。1968年 Traub报告了在邻国尼泊尔采到的另一种——三角继新蚤“(Evansipsylla thysanota Traub,1968)”,当时因为他漏看了长鬃继新蚤的文章而根据三角继新蚤建立了Evansipsylla属。后来Traub(1972)及Lewis(1974)相继都把Evansipsylla作为继新蚤属的同属异名,同时Lewis还疑惑三角继新蚤就是长鬃继新蚤。Brelih(1975)又根据在尼泊     

Effects of search experience in a resource-heterogeneous environment on the oviposition decisions of the seed beetle, Callosobruchus maculatus (F.)

Abstract.  1. This study investigates how female seed beetles, Callosobruchus maculatus , distribute their eggs on various-sized seeds when the size of seed was varied during the egg-laying period.
2. Beetles were allowed to lay eggs on one of three arrays of 64 adzuki beans ( Vigna angularis ). Each array contained four size classes of seed, ranging from small (5.0–5.5 mm diameter) to large (6.5–7.0 mm), but differed in how they were distributed within the environment. In the most heterogeneous condition (the 64-patch design), the four sizes were interspersed, while in the least heterogeneous condition (the four-patch design) they were grouped into four separate blocks. Thus, a beetle exploring the 64-patch design would frequently encounter all four seed sizes, whereas a beetle exploring the four-patch design would only rarely encounter a change in bean size.
3. Beetles experiencing greater seed size heterogeneity were more likely to lay eggs on larger seeds, whereas those in the blocked condition were more likely to oviposit on small seeds. Beetle responses to seed size heterogeneity suggest that the degree of preference for large seeds depends on a female's recent experience.
4. Female beetles exhibited size discrimination throughout their egg-laying process; however, there was a trade-off between seed size and egg discrimination (i.e. avoiding those seeds already containing developing eggs) in response to the change in fitness gained from either laying on larger seeds or lower egg-load seeds during the egg-laying process.
5. Our model provides the first evidence that evolving seed size discrimination ability is adaptive for the seed beetle with egg-discrimination ability.     

重庆市蚊虫初步调查

重庆地区的蚊虫调查,除过去甘怀杰(1942),周钦贤(1942—1944),张本华(1943—1944)等关于按蚊(Anopheles)的的调查外,以后尚乏人报告。1954年6月至9月,我们在沙磁区的杨公桥、石并坡、沙坪坝等地作了蚊虫的初步调查,共获蚊虫12种。其名称如下:     

Combined monte carlo and molecular dynamics simulation of fully hydrated dioleyl and palmitoyl-oleyl phosphatidylcholine lipid bilayers

We have applied a new equilibration procedure for the atomic level simulation of a hydrated lipid bilayer to hydrated bilayers of dioleyl-phosphatidylcholine (DOPC) and palmitoyl-oleyl phosphatidylcholine (POPC). The procedure consists of alternating molecular dynamics trajectory calculations in a constant surface tension and temperature ensemble with configurational bias Monte Carlo moves to different regions of the configuration space of the bilayer in a constant volume and temperature ensemble. The procedure is applied to bilayers of 128 molecules of POPC with 4628 water molecules, and 128 molecules of DOPC with 4825 water molecules. Progress toward equilibration is almost three times as fast in central processing unit (CPU) time compared with a purely molecular dynamics (MD) simulation. Equilibration is complete, as judged by the lack of energy drift in 200-ps runs of continuous MD. After the equilibrium state was reached, as determined by agreement between the simulation volume per lipid molecule with experiment, continuous MD was run in an ensemble in which the lateral area was restrained to fluctuate about a mean value and a pressure of 1 atm applied normal to the bilayer surface. Three separate continuous MD runs, 200 ps in duration each, separated by 10,000 CBMC steps, were carried out for each system. Properties of the systems were calculated and averaged over the three separate runs. Results of the simulations are presented and compared with experimental data and with other recent simulations of POPC and DOPC. Analysis of the hydration environment in the headgroups supports a mechanism by which unsaturation contributes to reduced transition temperatures. In this view, the relatively horizontal orientation of the unsaturated bond increases the area per lipid, resulting in increased water penetration between the headgroups. As a result the headgroup-headgroup interactions are attenuated and shielded, and this contributes to the lowered transition temperature.     

防止逃鱼用的拦网和拦栅的合理规格的研究

目前一般较大的湖泊水库放养鱼类的回捕率颇低,逃鱼是重要原因之一。为了确定拦鱼用的网和栅所应采取的规格,测量了2,227尾(3—16厘米)鲢、鳙、草、青鱼种的全长,最大周长、头宽、颅宽的各个数值,推算出全长与最大周长、头宽、颅宽的迥归方程式及它们的95%的可信限。通过实验,观察到在流水条件下,鱼种能溯水穿越较自身最大周长为小的拦网网目或较头宽为小的拦栅栅距而逃逸。作者称这种能力为“穿拦系数”(用Kg 或Kp 表示)。并测出在武昌东湖某些生活污水进水口处,1973年3—4月份白鲢鱼种的穿拦系数按Kg 计算为1.5,按Kp 计算为1.2。作者建议在静水或出水口处,设置拦鱼用的拦网的网目长度不得超过所投放色种的最大周长的95%的可信限的下限的1/2,各种拦栅的栅距不得超过鱼种的头宽的95%可信限的下限。而在流水条件下,在确定所应采取的拦网网目或拦栅栅距时,还应该考虑“穿拦系数”在内。文末附有检索表,列举了鲢、鳙、草、青鱼种(3—16厘米)相应于全长值的最大周长值、头宽值、颅宽值以及它们的95%可信限的上限和下限的各个数值,供确定拦网网目和拦栅栅距的规格时参考。       

Duplicate <Emphasis Type="Italic">dmbx1</Emphasis>genes regulate progenitor cell cycle and differentiation during zebrafish midbrain and retinal development

Background  

The Dmbx1 gene is important for the development of the midbrain and hindbrain, and mouse gene targeting experiments reveal that this gene is required for mediating postnatal and adult feeding behaviours. A single Dmbx1 gene exists in terrestrial vertebrate genomes, while teleost genomes have at least two paralogs. We compared the loss of function of the zebrafish dmbx1a and dmbx1b genes in order to gain insight into the molecular mechanism by which dmbx1 regulates neurogenesis, and to begin to understand why these duplicate genes have been retained in the zebrafish genome.     

Systematics and phylogeography of the Taiwanese endemic minnow Candidia barbatus (Pisces: Cyprinidae) based on DNA sequence,allozymic, and morphological analyses

The phylogeographical patterns of the endemic minnow, Candidia barbatus, were examined using mitochondrial (mt) cytochrome b sequences, allozyme electrophoresis, and morphology. The 23 mtDNA haplotypes recovered were grouped into six lineages (A–F). According to a molecular clock of 1.7% per million years, we estimated that the colonization of C. barbatus to Taiwan took place three million years ago with several subsequent vicariance events. In the allozyme analysis, the Bayesian approach partitioned different populations into three clusters, with clusters I, II, and III mainly found in northern, central, and southern Taiwan, respectively. Morphologically, fish from north and south of the Tropic of Cancer had distinct numbers of lateral line scales and were separated into two morphs. The cohabitation of different mtDNA lineages with high allozymic and morphological similarities suggests that interbreeding amongst them is possible. Therefore, in spite of highly differentiated mtDNA, samples from different collecting sites should be considered a single species. Based on the current population distribution and levels of divergence, we propose that both orogenic activities and marine regression during glacial epoch were the two main forces shaping population differentiation of this species. © 2011 The Linnean Society of London, Zoological Journal of the Linnean Society, 2011, 161 , 613–632.     

鲟科鱼类寄生粘孢子虫二新种(粘孢子虫纲:双壳目:碘泡科)

在长江中游的扬子江白鲟和中华鲟上发现二种粘孢子虫,命名为白鲟碘泡虫,新种和宜都单极虫,新种。