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1.
Allopatric isolation in glacial refugia has caused differentiation and speciation in many taxa globally. In this study, we investigated the nuclear and mitochondrial genetic differentiation of the long fingered bat, Myotis capaccinii during the ice ages in south-eastern Europe and Anatolia. The mitochondrial DNA (mtDNA) analyses indicated a suture zone similar to those recorded in other animal species, including bats, suggesting the association of more than one refugium with the region. Contrary to most of the other species where a suture zone was seen in Anatolia, for M. capaccinii the geographical location of the genetic break was in south-eastern Europe. This mitochondrial differentiation was not reflected in the nuclear microsatellites, however, suggesting that the lack of contact during the ice ages did not result in reproductive isolation. Hence taxonomically, the two mitochondrial clades cannot be treated as separate species. 相似文献
2.
Cokun Kse Evren Terzi S. Nami Kartal 《International biodeterioration & biodegradation》2009,63(6):727-731
This study evaluated the relative ability of various combinations of copper sulfate with either boric acid or calcium-precipitating agent, N′-N-(1, 8-naphthalyl) hydroxylamine (NHA-Na), to inhibit fungal degradation and attack by Formosan subterranean termites (Coptotermes formosanus Shiraki). Wood specimens were treated with either 1%, 0.5%, or 0.1% concentrations of copper sulfate, boric acid, NHA-Na, copper sulfate + boric acid, or copper sulfate + NHA-Na mixtures. Treated specimens were subjected to laboratory decay-resistance tests by using petri dishes inoculated with the Basidiomycetes fungi Tyromyces palustris and Trametes versicolor for 12 weeks. Treated wood specimens were also subjected to termite-resistance tests under laboratory conditions. Increased efficacy of copper sulfate against the brown-rot fungus T. palustris was observed when either boric acid or NHA-Na was added. The most effective treatments against the fungi tested were NHA-Na only treatments at 1% and 0.5% concentration levels. Boric acid treatments were not able to protect wood against decay after leaching because of excessive leaching of boron. Similar results were obtained in termite-resistance tests in comparison with decay-resistance tests. These results indicate that the efficacy of the treatments in preventing fungal and termite attack is a function of the type of preservative. 相似文献
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A new dihydroflavonol, pallasiin, together with kaempferol, quercetin, isorhamnetin, mearnsetin, aromadendrin, eriodictyol and taxifolin, has been isolated from the bark of Rhamnus pallasii and its structure elucidated as 2,3-dihydromyricetin 4′-O-methyl ether. 相似文献
7.
I. Alteraş M. D. 《Mycopathologia》1966,28(4):361-367
Summary
Trichophyton quinckeanum was isolated from a spontaneous infection in rabbit. The hairs were also invaded by the fungus, exibiting a yellowish fluorescence in Wood's light. White mice inoculation of the isolate produced typical scutula with hair penetration fluorescing in green colour. The type of animal hair invasion is also discussed. The morphologic features ofTr. quinckeanum, together with its ability of producing scutula while inoculating the white mice, must be emphasized, when proving its separate identity. 相似文献
8.
Mariana Beliş 《Biological cybernetics》1967,3(5):238-240
Summary The formation of the interconnection stimulus-response in a learning system is analysed. The system, a technical or a biological one establishes this correspondence by processing the information fed back from the medium during the learning process. This information has two aspects: a quantitative one related to the probability of the events, and a qualitative one related to the utility of the events in view of a goal. Both aspects are taken into consideration; by successive experiences the system eliminates the double uncertainty concerning the probabilistic dependence: stimulu — sresponse — outcome and its utility. Learning implies then a system for evaluating the utilities of different outcomes in view of a goal, a memory to record them and a decision system for selecting the corresponding responses upon a given criterion.
Der Beitrag stellt einen Teil der Untersuchungen dar, die zur Ausarbeitung der Doktor-Dissertation am Polytechnischen Institut Gheorghe Gheorghiu-Dej in Bukarest unternommen wurden. 相似文献
Der Beitrag stellt einen Teil der Untersuchungen dar, die zur Ausarbeitung der Doktor-Dissertation am Polytechnischen Institut Gheorghe Gheorghiu-Dej in Bukarest unternommen wurden. 相似文献
9.
E Breslow R T Co P Hanna T Laborde 《International journal of peptide and protein research》1989,34(1):21-27
Circular dichroism was used to compare the environment of peptides bound to native and des 1-8 neurophysin in order to further elucidate the role of the neurophysin 1-8 sequence in peptide-binding. A very large positive ellipticity (approximately 6000 deg cm2 dmol-1), shown earlier to be induced in tyrosine at position 2 of peptides bound to the native protein, was determined by the present study to be paralleled by similar induced changes in tyrosine at peptide position 1. Deletion of the neurophysin 1-8 sequence led to loss of half of the induced optical activity at peptide positions 1 and 2 and changes in binding-induced optical activity in the protein, the latter partially assignable to protein disulfides. In the mononitrated native and des 1-8 proteins, the optical activity of neurophysin Tyr-49, a residue at the peptide-binding site, was reduced by 80% in complexes of the des 1-8 protein relative to those of the native protein. The results suggest a role for neurophysin Arg-8 in modulating the optical activity at the binding site by directly placing a charge proximal to the binding site and/or by altering binding site conformation. The data provide the first unambiguous evidence of a difference in the environment of bound peptide between the native and des 1-8 proteins. 相似文献
10.
中国普通野生稻遗传分化的RAPD研究 总被引:18,自引:0,他引:18
多数学者已认定亚洲栽培稻(OryzasativaL.)的祖先是普通野生稻(O.rufipogon)。然而栽培稻的籼、粳分化是发生在驯化之前还是在驯化之后,也即普通野生稻是否存在籼、粳分化的问题,是十几年来稻作起源研究中争论的热点之一。Second[1]用多个同工酶位点的分析结果得出结论,普通野生稻在驯化为栽培稻之前就已经发生了籼、粳分化,即有籼型普通野生稻和粳型普通野生稻之分。Morishima和Gadrinab[2]用24个形态和生理性状及12个同工酶位点和杂交亲合力等方法证明普通野生稻没有发… 相似文献