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951.
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Jing Wang XiaoYun Wu ZiMing Chen ZhaoPing Yue Wei Ma ShanYuan Chen Heng Xiao Robert W. Murphy YaPing Zhang RuiGuang Zan Jing Luo 《科学通报(英文版)》2013,58(31):3738-3746
The phylogenetic relationships of European and African Barbus and their West Asian relatives in Cyprininae remain largely unresolved. Consequently, little is known about the drivers of their evolution, including the possible association of uplifting of the Qinghai-Tibetan Plateau (QTP) with the early divergence of the subfamily. We use complete sequence data of the mitochondrial DNA gene encoding the protein cytochrome b (Cytb) to hypothesize the phylogeny of 85 species belonging to 47 genera in the Cyprininae plus 6 species from the Leuciscinae. We employ 6 other species from Cypriniformes as outgroup taxa and estimate divergence times. Our results indicate that European Barbus sensu stricto lineage including Aulopyge shares a common ancestor with specialized and highly specialized schizothoracins and the genera Cyprinion and Scaphiodonichtys. The common ancestor appears to have originated in the Qinghai-Tibetan Plateau (QTP) region about 19.4–17.8 Ma. Barbus sensu stricto lineage appears to have originated about 16.6–15.5 Ma. Small to medium sized African Barbus sensu lato appear to have had an Oriental origin about 19.1–15.3 Ma and are closely related to Asian Puntius. West Asian Carasobarbus lineage including large African Barbus sensu lato might have originated about 9.94 Ma, also in Oriental Realm and has a close relationship to Asian Neolissochilus and Tor. The large-sized Barbus sensu lato appear to have diverged from Carasobarbus about 7.7 Ma. Finally, the Cyprininae appear to have radiated rapidly into nine lineages and many sublineages from about 27.8 to 17.8 Ma, close to the time of the second-stage tectonic movements of the QTP. Our analyses provide evidence that the uplifting of the QTP drove early diversification of the Cyprininae. Our extensive sampling of species involving all of the important areas results in clear evolutionary scenario for the Cyprininae. 相似文献
954.
Bluehead sucker ( Catostomus discobolus ) and flannelmouth sucker ( Catostomus latipinnis ) populations are declining throughout these species’ native ranges in the Upper Colorado River Basin. In order to conserve these populations, an understanding of population dynamics is needed. Using age estimates from pectoral fin rays, we describe age and growth of these 2 species in 3 Wyoming stream systems: Muddy Creek, the Little Sandy River, and the Big Sandy River. Within all 3 stream systems, flannelmouth suckers were longer-lived than bluehead suckers, with maximum estimated ages of 16 years in Muddy Creek, 18 years in Little Sandy Creek, and 26 years in the Big Sandy River. Bluehead suckers had maximum estimated ages of 8 years in Muddy Creek, 10 years in Little Sandy Creek, and 18 years in the Big Sandy River. These maximum estimated ages were substantially greater than in other systems where scales have been used to estimate ages. Mean lengths at estimated ages were greater for flannelmouth suckers than for bluehead suckers in all 3 streams and generally less than values published from other systems where scales were used to estimate ages. Our observations of long life spans and slow growth rates among bluehead suckers and flannelmouth suckers were probably associated with our use of fin rays to estimate ages as well as the populations being in headwater tributaries near the northern edges of these species’ ranges. 相似文献
955.
Robert C. Bishop 《Studies in History and Philosophy of Science Part B: Studies in History and Philosophy of Modern Physics》2010,41(2):171-177
Along with exploring some of the necessary conditions for the chemistry of our world given what we know about quantum mechanics, I will also discuss a different reductionist challenge than is usually considered in debates on the relationship of chemistry to physics. Contrary to popular belief, classical physics does not have a reductive relationship to quantum mechanics and some of the reasons why reduction fails between classical and quantum physics are the same as for why reduction fails between chemistry and quantum physics. However, a neoreductionist can accept that classical physics has some amount of autonomy from quantum mechanics, but still try to maintain that classical+quantum physics taken as a whole reduces chemistry to physics. I will explore some of the obstacles lying in the neoreductionist's path with respect to quantum chemistry and thereby hope to shed more light on the conditions necessary for the chemistry of our world. 相似文献
956.
Václav Čeřovský Jan Žďárek Vladimír Fučík Lenka Monincová Zdeněk Voburka Robert Bém 《Cellular and molecular life sciences : CMLS》2010,67(3):455-466
A novel homologue of insect defensin designated lucifensin (Lucilia defensin) was purified from the extracts of various tissues (gut, salivary glands, fat body, haemolymph) of green bottle
fly (Lucilia
sericata) larvae and from their excretions/secretions. The primary sequence of this peptide of 40 residues and three intramolecular
disulfide bridges was determined by ESI-QTOF mass spectrometry and Edman degradation and is very similar to that of sapecin
and other dipteran defensins. We assume that lucifensin is the key antimicrobial component that protects the maggots when
they are exposed to the highly infectious environment of a wound during the medicinal process known as maggot therapy. We
also believe that lucifensin is that long-sought larger molecular weight antimicrobial factor of the Lucilia sericata excretions/secretions believed to be effective against pathogenic elements of the wound microbial flora. 相似文献
957.
Robert E. Criss 《地球科学学刊》2015,(1)
Fluid-rock interactions alter the geochemical, isotopic, petrographic and physical character of host rocks, producing a permanent record of hydrothermal activity. Maps of altered rock properties show r... 相似文献
958.
Five species of the coccidian genus Eimeria ( E. beecheyi [prevalence = 17.9%], E. callospermophili-morainensis [28.6%], E. larimerensis [16.1%], and E. bilamellata [3.6%]) were recovered from 56, 13-lined ground squirrels ( Spermophilus tridicemlineatus ) collected from two sites in eastern Wyoming. Two squirrels from one site were also passing an unidentified polysporocystic coccidian. Infected squirrels were found to harbor from one to three species simultaneously. Previously these same eimerian species were found infecting sympatric populations of Wyoming ground squirrels. ( Spermophilus elegans ) and white-tailed prairie dogs ( Cynomys leacurus ) at one of the sites; it is suggested that the exchange of these generalist parasite species among co-occurring sciurid hosts contributes to the consistent prevalence levels reported in Wyoming ground squirrels. 相似文献
959.
Robert C. Scharff 《Foundations of Science》2013,18(2):393-397
Hans Ruin and Patrick Heelan join me in celebrating the rise of post-positivist and phenomenological approaches to scientific and technological practice. Yet as they both know, I am also concerned that the very presence of all the new accounts which give voice to this trend may tempt us into concluding prematurely that the traditional understanding of science and technology has already been displaced. With especially Ruin’s encouragement, I expand my original discussion of this concern by explaining why I agree with him about the ontologically mistaken suppositions that one might become post-positivistic by doing philosophy “meta-philosophically,” or become phenomenological by making “life” more basic that “nature.” 相似文献
960.