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101.
Silici Sibel Ünlü Mehmet Vardar-Ünlü Gülhan 《World journal of microbiology & biotechnology》2009,25(2):355-355
World Journal of Microbiology and Biotechnology - 相似文献
102.
ZUZANA MÜNZBERGOVÁ 《Botanical journal of the Linnean Society. Linnean Society of London》2009,160(3):290-298
In spite of the large number of studies on genome size, studies comparing genome size and growth‐related traits across a wider range of species from the same habitat, taking into account species phylogeny, are largely missing. I estimated the relationship between genome size and different seed and seedling traits in perennial herbs occurring in dry calcareous grasslands in northern Bohemia, Czech Republic. There was no relationship between genome size and plant traits in simple regression analyses, but several strong relationships emerged in analyses based on pairwise phylogenetically independent contrasts. There was a significant relationship between monoploid genome size and production of above‐ground biomass, seedling establishment success and seed weight and between holoploid genome size and seed dormancy. Because the results are based on phylogenetically independent contrasts over a range of species from the same type of habitat, they allow me to conclude that these patterns were not because of species group or habitat type, but really show a correlation with genome size. In contrast to previous studies, I found a higher number of relationships with monoploid than with holoploid genome size. This may be because the traits observed in this study are directly related to plant growth and thus to life‐cycle time, which is determined by monoploid genome size. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 160 , 290–298. 相似文献
103.
STEFANIE KLUG JÜRGEN KRIWET RONALD BÖTTCHER GÜNTER SCHWEIGERT GERD DIETL 《Zoological Journal of the Linnean Society》2009,157(1):107-134
The skeletal morphology of Paraorthacodus jurensis, a Late Jurassic neoselachian from Nusplingen, is described based on the incomplete holotype and a newly discovered almost complete specimen. For the first time, the postcranial skeleton could be investigated. Paraorthacodus is characterized by a monognath dental heterodonty and tearing‐type dentition. The number of lateral cusplets in the lateral teeth differs between the holotype and the new specimen, possibly indicating sexual dimorphism. Clasper organs are not preserved in either of the two specimens. The notochord is sheathed by about 123 well‐calcified vertebral centra. The posterior‐most caudal vertebrae are lacking. The transition from monospondylous thoracic to diplospondylous abdominal vertebrae occurs at centra 48 and 49. The origin of the caudal fin is at the 80th centrum. Most conspicuous is the presence of a single spineless dorsal fin. In this respect, Paraorthacodus differs from most palaeospinacids, but resembles Macrourogaleus. Palidiplospinax possibly is sister to a group comprising Synechodus, Paraorthacodus, and Macrourogaleus (the Palaeospinacidae). A reinterpretation of dental and skeletal characters of synechodontiform taxa indicates that Synechodontiformes and Palaeospinacidae are monophyletic groupings of basal neoselachians. Synechodontiformes is probably sister to all living elasmobranchs. 相似文献
104.
105.
Gerard Farré‐Armengol Iolanda Filella Joan Llusià Ülo Niinemets Josep Peñuelas 《Global Change Biology》2014,20(12):3660-3669
We addressed the potential effects of changes in ambient temperature on the profiles of volatile emissions from flowers and tested whether warming could induce significant quantitative and qualitative changes in floral emissions, which would potentially interfere with plant–pollinator chemical communication. We measured the temperature responses of floral emissions of various common species of Mediterranean plants using dynamic headspace sampling and used GC‐MS to identify and quantify the emitted terpenes. Floral emissions increased with temperature to an optimum and thereafter decreased. The responses to temperature modeled here predicted increases in the rates of floral terpene emission of 0.03–1.4‐fold, depending on the species, in response to an increase of 1 °C in the mean global ambient temperature. Under the warmest projections that predict a maximum increase of 5 °C in the mean temperature of Mediterranean climates in the Northern Hemisphere by the end of the century, our models predicted increases in the rates of floral terpene emissions of 0.34–9.1‐fold, depending on the species. The species with the lowest emission rates had the highest relative increases in floral terpene emissions with temperature increases of 1–5 °C. The response of floral emissions to temperature differed among species and among different compounds within the species. Warming not only increased the rates of total emissions, but also changed the ratios among compounds that constituted the floral scents, i.e. increased the signal for pollinators, but also importantly altered the signal fidelity and probability of identification by pollinators, especially for specialists with a strong reliance on species‐specific floral blends. 相似文献
106.
Controls of the quantum yield and saturation light of isoprene emission in different‐aged aspen leaves 下载免费PDF全文
Leaf age alters the balance between the use of end‐product of plastidic isoprenoid synthesis pathway, dimethylallyl diphosphate (DMADP), in prenyltransferase reactions leading to synthesis of pigments of photosynthetic machinery and in isoprene synthesis, but the implications of such changes on environmental responses of isoprene emission have not been studied. Because under light‐limited conditions, isoprene emission rate is controlled by DMADP pool size (SDMADP), shifts in the share of different processes are expected to particularly strongly alter the light dependency of isoprene emission. We examined light responses of isoprene emission in young fully expanded, mature and old non‐senescent leaves of hybrid aspen (Populus tremula x P. tremuloides) and estimated in vivo SDMADP and isoprene synthase activity from post‐illumination isoprene release. Isoprene emission capacity was 1.5‐fold larger in mature than in young and old leaves. The initial quantum yield of isoprene emission (αI) increased by 2.5‐fold with increasing leaf age primarily as the result of increasing SDMADP. The saturating light intensity (QI90) decreased by 2.3‐fold with increasing leaf age, and this mainly reflected limited light‐dependent increase of SDMADP possibly due to feedback inhibition by DMADP. These major age‐dependent changes in the shape of the light response need consideration in modelling canopy isoprene emission. 相似文献
107.
108.
First record of red cornetfish Fistularia petimba (Syngnathiformes:Fistulariidae) from Antalya and İskenderun Bays along Turkish Coasts of the Mediterranean Sea 下载免费PDF全文
A. Ünlüoğlu S. Akalın İ. Dal E. M. Tıraşın C. M. Aydın 《Zeitschrift fur angewandte Ichthyologie》2018,34(4):977-980
Here, we report the first occurrence of red cornetfish Fistularia petimba in the north‐eastern Mediterranean Sea. Altogether four specimens were captured; first two in Antalya Bay on 28 October 2016 and 26 November 2016, and the remaining two in ?skenderun Bay on 21 May 2017 during the bottom trawl surveys along the Mediterranean coast of Turkey. All specimens were young and more or less uniform in size (383, 335, 419 and 453 mm standard length). The possibility that F. petimba could become a new potential invader in the Mediterranean as its congeneric F. commersonii is cautioned against. 相似文献
109.
110.
Nieves M De Oliveira EH Amaral PJ Nagamachi CY Pieczarka JC Mühlmann MC Mudry MD 《Journal of genetics》2011,90(1):111-117
The karyotype of the neotropical primate genus Cebus (Platyrrhini: Cebidae), considered the most ancestral one, shows the greatest amount of heterochromatin described among Platyrrhini
genera. Banding techniques and restriction enzyme digestion have previously revealed great variability of quantity and composition
of heterochromatin in this genus. In this context, we use fluorescence in situ hybridization (FISH) to analyse this genomic region and discuss its possible role in the diversification of Cebus. We used a heterochromatin probe for chromosome 11 of Cebus libidinosus (11qHe+ CLI probe), obtained by chromosome microdissection. Twenty-six specimens belonging to the families Atelidae, Cebidae,
Callitrichidae and Pithecidae (Platyrrhini) were studied. Fourteen out of 26 specimens were Cebus (Cebidae) individuals of C. libidinosus, C. xanthosternos, C. apella, C. nigritus, C. albifrons, C. kaapori and C. olivaceus. In Cebus specimens, we found 6 to 22 positive signals located in interstitial and telomeric positions along the different species.
No hybridization signal was observed among the remaining Ceboidea species, thus reinforcing the idea of a Cebus-specific heterochromatin composed of a complex system of repetitive sequences. 相似文献