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821.
Modelling the distribution and compositional variation of plant communities at the continental scale 下载免费PDF全文
Borja Jiménez‐Alfaro Susana Suárez‐Seoane Milan Chytrý Stephan M. Hennekens Wolfgang Willner Michal Hájek Emiliano Agrillo Jose M. Álvarez‐Martínez Ariel Bergamini Henry Brisse Jörg Brunet Laura Casella Daniel Dítě Xavier Font François Gillet Petra Hájková Florian Jansen Ute Jandt Zygmunt Kącki Jonathan Lenoir John S. Rodwell Joop H. J. Schaminée Lucia Sekulová Jozef Šibík Željko Škvorc Ioannis Tsiripidis 《Diversity & distributions》2018,24(7):978-990
Aim
We investigate whether (1) environmental predictors allow to delineate the distribution of discrete community types at the continental scale and (2) how data completeness influences model generalization in relation to the compositional variation of the modelled entities.Location
Europe.Methods
We used comprehensive datasets of two community types of conservation concern in Europe: acidophilous beech forests and base‐rich fens. We computed community distribution models (CDMs) calibrated with environmental predictors to predict the occurrence of both community types, evaluating geographical transferability, interpolation and extrapolation under different scenarios of sampling bias. We used generalized dissimilarity modelling (GDM) to assess the role of geographical and environmental drivers in compositional variation within the predicted distributions.Results
For the two community types, CDMs computed for the whole study area provided good performance when evaluated by random cross‐validation and external validation. Geographical transferability provided lower but relatively good performance, while model extrapolation performed poorly when compared with interpolation. Generalized dissimilarity modelling showed a predominant effect of geographical distance on compositional variation, complemented with the environmental predictors that also influenced habitat suitability.Main conclusions
Correlative approaches typically used for modelling the distribution of individual species are also useful for delineating the potential area of occupancy of community types at the continental scale, when using consistent definitions of the modelled entity and high data completeness. The combination of CDMs with GDM further improves the understanding of diversity patterns of plant communities, providing spatially explicit information for mapping vegetation diversity and related habitat types at large scales.822.
Zahra Ghasemi Carmela Monterroso Petra S. Kidd 《International journal of phytoremediation》2018,20(7):699-708
Phytomining techniques based on metal-hyperaccumulating plants can be implemented in serpentine quarry wastes for Ni recovery. However, strategies must be developed to overcome the unfavourable plant growth conditions that these substrates present and to optimize Ni yields. In this study, the Ni hyperaccumulators Alyssum serpyllifolium, Alyssum inflatum, and Alyssum bracteatum were evaluated for their Ni phytoextraction efficiency from quarry tailings. Effects of two organic amendments, composted municipal sewage sludge and cow manure, on plant growth and physiological status and Ni removal were determined. Organic amendments were incorporated at two addition rates (5% and 20% w/w). The best-performing hyperaccumulators were A. inflatum and A. serpyllifolium. Organic amendments improved plant biomass production, photosynthetic efficiency and nutrition, but reduced shoot Ni concentrations. However, the stimulation in biomass resulted in significantly enhanced Ni yields. The most promising results were found using low addition rates and after manure incorporation. 相似文献
823.
Sudheer Babu Sangeetham Krisztina Huszár Petra Bencsura Antal Nyeste Éva Hunyadi-Gulyás Elfrieda Fodor Ervin Welker 《Journal of molecular biology》2018,430(17):2784-2801
Transmissible spongiform encephalopathies are centered on the conformational transition of the prion protein from a mainly helical, monomeric structure to a β-sheet rich ordered aggregate. Experiments indicate that the main infectious and toxic species in this process are however shorter oligomers, formation of which from the monomers is yet enigmatic. Here, we created 25 variants of the mouse prion protein site-specifically containing one genetically-incorporated para-benzoyl-phenylalanine (pBpa), a cross-linkable non-natural amino acid, in order to interrogate the interface of a prion protein-dimer, which might lie on the pathway of oligomerization. Our results reveal that the N-terminal part of the prion protein, especially regions around position 127 and 107, is integral part of the dimer interface. These together with additional pBpa-containing variants of mPrP might also facilitate to gain more structural insights into oligomeric and fibrillar prion protein species including the pathological variants. 相似文献
824.
Divergent in shape and convergent in function: Adaptive evolution of the mandible in Sub‐Antarctic mice 下载免费PDF全文
Sabrina Renaud Ronan Ledevin Benoit Pisanu Jean‐Louis Chapuis Petra Quillfeldt Emilie A. Hardouin 《Evolution; international journal of organic evolution》2018,72(4):878-892
Convergent evolution in similar environments constitutes strong evidence of adaptive evolution. Transported with people around the world, house mice colonized even remote areas, such as Sub‐Antarctic islands. There, they returned to a feral way of life, shifting towards a diet enriched in terrestrial macroinvertebrates. Here, we test the hypothesis that this triggered convergent evolution of the mandible, a morphological character involved in food consumption. Mandible shape from four Sub‐Antarctic islands was compared to phylogeny, tracing the history of colonization, and climatic conditions. Mandible shape was primarily influenced by phylogenetic history, thus discarding the hypothesis of convergent evolution. The biomechanical properties of the jaw were then investigated. Incisor in‐lever and temporalis out‐lever suggested an increase in the velocity of incisor biting, in agreement with observations on various carnivorous and insectivorous rodents. The mechanical advantage related to incisor biting also revealed an increased functional performance in Sub‐Antarctic populations, and appears to be an adaptation to catch prey more efficiently. The amount of change involved was larger than expected for a plastic response, suggesting microevolutionary processes were evolved. This study thus denotes some degree of adaptive convergent evolution related to changes in habitat‐related changes in dietary items in Sub‐Antarctic mice, but only regarding simple, functionally relevant aspects of mandible morphology. 相似文献
825.
Antisense Therapy for a Common Corneal Dystrophy Ameliorates TCF4 Repeat Expansion-Mediated Toxicity
Christina Zarouchlioti Beatriz Sanchez-Pintado Nathaniel J. Hafford Tear Pontus Klein Petra Liskova Kalyan Dulla Ma’ayan Semo Anthony A. Vugler Kirithika Muthusamy Lubica Dudakova Hannah J. Levis Pavlina Skalicka Pirro Hysi Michael E. Cheetham Stephen J. Tuft Peter Adamson Alison J. Hardcastle Alice E. Davidson 《American journal of human genetics》2018,102(4):528-539
826.
Petra Lassuthova Adriana P. Rebelo Gianina Ravenscroft Phillipa J. Lamont Mark R. Davis Fiore Manganelli Shawna M. Feely Chelsea Bacon Dana Šafka Brožková Jana Haberlova Radim Mazanec Feifei Tao Cima Saghira Lisa Abreu Steve Courel Eric Powell Elena Buglo Dana M. Bis Stephan Zuchner 《American journal of human genetics》2018,102(3):505-514
827.
Petra Kraus Rachel Yerden Darren Sipes Shantanu Sur Thomas Lufkin 《Cytotechnology》2018,70(1):185-192
Cells are often characterized by their gene expression profile. However, commonly used methods to detect mRNA require cell pooling and could therefore mask differences in gene expression within heterogeneous cell populations. q2PISH allows for the analysis of both qualitative and quantitative (q2) gene expression on cultured cells for quality control measures with single cell resolution. q2PISH was optimized for the subsequent use of two alkaline phosphatase substrates in combination with a cell nucleus count to allow for accurate quantification of gene expression per cell and simultaneously qualitative assessment of potential culture population drift or heterogeneity. As proof of principle the assay was applied to cell lines derived from different areas of the bovine intervertebral disc, showing significant difference in the expression of Col1a1, Col2a1, Acan and Sox9. Furthermore, the assay served to explore a potential impact on cultured cells when substituting a critical media component, fetal bovine serum (FBS), suggesting no significant difference in gene expression for the biomarkers analyzed. As a tool, q2PISH serves as an accurate quality control with single cell resolution for cultured cells. 相似文献
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