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161.
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163.
Sanna Olsson Volker Buchbender Johannes Enroth Lars Hedenäs Sanna Huttunen Dietmar Quandt 《Organisms Diversity & Evolution》2010,10(2):107-122
The family Neckeraceae is composed of three distinct clades, of which two, i.e. the Neckera and Thamnobryum clades, are well defined. The third clade, consisting of species belonging to Caduciella, Curvicladium, Handeliobryum, Himantocladium, Homaliodendron, Hydrocryphaea, Neckera, Neckeropsis, Pinnatella, Shevockia and Taiwanobryum, is the focus of this study. Based on sequence data from the trnS-rps4-trnT-trnL-trnF plastid cluster and the rpl16 intron as well as from nuclear ITS1&2, the phylogenetic relationships of these genera are reconstructed. The nearest relatives
of this clade are resolved shedding more light on the evolution of the family. The generic composition of the clade and its
individual genera are discussed; polyphyly requires redefinition of Pinnatella, Neckeropsis and Homaliodendron. The positions of Touwia and Homalia within the family are addressed in an additional analysis based on more extensive sequence data, and the corresponding new
combinations are made. Several further taxonomic changes are proposed, including Circulifolium gen. nov., comprising the former Homaliodendron exiguum and H. microdendron. 相似文献
164.
165.
Spatial and seasonal variation in greenhouse gas and nutrient dynamics and their interactions in the sediments of a boreal eutrophic lake 总被引:1,自引:0,他引:1
Anu Liikanen Jari T. Huttunen Timo Murtoniemi Heikki Tanskanen Tero Väisänen Jouko Silvola Jukka Alm Pertti J. Martikainen 《Biogeochemistry》2003,65(1):83-103
Dynamics of greenhouse gases, CH4, CO2 and N2O, and nutrients, NO
2
–
+ NO
3
–
, NH
4
+
and P, were studied in the sediments of the eutrophic, boreal Lake Kevätön in Finland. Undisturbed sediment cores taken in the summer, autumn and winter from the deep and shallow profundal and from the littoral were incubated in laboratory microcosms under aerobic and anaerobic water flow conditions. An increase in the availability of oxygen in water overlying the sediments reduced the release of CH4, NH
4
+
and P, increased the flux of N2O and NO
2
–
+ NO
3
–
, but did not affect CO2 production. The littoral sediments produced CO2 and CH4 at high rates, but released only negligible amounts of nutrients. The deep profundal sediments, with highest carbon content, possessed the greatest release rates of CO2, CH4, NH
4
+
and P. The higher fluxes of these gases in summer and autumn than in winter were probably due to the supply of fresh organic matter from primary production. From the shallow profundal sediments fluxes of CH4, NH4
+ and P were low, but, in contrast, production of N2O was the highest among the different sampling sites. Due to the large areal extension, the littoral and shallow profundal zones had the greatest importance in the overall gas and nutrient budgets in the lake. Methane emissions, especially the ebullition of CH4 (up to 84% of the total flux), were closely related to the sediment P and NH
4
+
release. The high production and ebullition of CH4, enhances the internal loading of nutrients, lake eutrophication status and the impact of boreal lakes to trophospheric gas budgets. 相似文献
166.
167.
Annemarie MM Vlaar Tjerk de Nijs Marinus JPG van Kroonenburgh Werner H Mess Ania Winogrodzka Selma C Tromp Wim EJ Weber 《BMC neurology》2008,8(1):42
Background
Transcranial duplex sonography (TCD) of the substantia nigra has emerged as a promising, non-invasive tool to diagnose idiopathic Parkinson's disease (IPD). However, its diagnostic accuracy in patients with undefined parkinsonism remains to be determined. 相似文献168.
Coregulation of neurite outgrowth and cell survival by amphoterin and S100 proteins through receptor for advanced glycation end products (RAGE) activation 总被引:18,自引:0,他引:18
Huttunen HJ Kuja-Panula J Sorci G Agneletti AL Donato R Rauvala H 《The Journal of biological chemistry》2000,275(51):40096-40105
169.
We used a set of 48 polymorphic microsatellites derived from Drosophila virilis to infer phylogenetic relationships in the D. virilis clade. Consistent with previous studies, D. virilis and D. lummei were the most basal species of the group. Within the D. montana phylad, the phylogenetic relationship could not be resolved. Special attention was given to the differentiation between D. americana texana, D. americana americana and D. novamexicana. Significant differences between these three groups were detected by F(ST) analyses. Similarly, a model-based clustering method for multilocus genotype data also provided strong support for the presence of three differentiated groups. This genome-wide differentiation between D. americana texana and D. americana americana contrasts with previous analyses based on DNA sequence data. 相似文献
170.
We have used a quantitative trait locus (QTL) mapping approach to study the genetic basis of differences between two Drosophila virilis strains representing extreme phenotypes in two song characters, the number of pulses in a pulse train (PN) and the length of a pulse train (PTL). Variation in these characters among 520 F2 males was studied by single-marker analysis and composite interval mapping (CIM) using a recombination linkage map constructed for 26 microsatellite markers. In single-marker analysis, two adjacent microsatellite markers on the third chromosome, msat19 and vir84 explained 13.8 and 12.4% of the variation in PN and 9.9 and 6.5% of the variation in PTL, respectively. CIM analysis revealed significant QTLs affecting PN, located on the X and the second, third and fourth chromosome of D. virilis, while variation in PTL was attributable to QTLs located only on the third chromosome. 相似文献