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31.
Faize Mohamed Faize Lydia Alburquerque Nuria Venisse Jean Stéphane Burgos Lorenzo 《Molecular biology reports》2020,47(8):5889-5901
Molecular Biology Reports - H2O2 generated during the oxidative burst, plays important roles in plant defenses responses against pathogens. In this study we examined the role of H2O2 on bacterial... 相似文献
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Derya Akkaynak Justine J. Allen Lydia M. Mäthger Chuan-Chin Chiao Roger T. Hanlon 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2013,199(3):211-225
Cephalopods are renowned for their ability to adaptively camouflage on diverse backgrounds. Sepia officinalis camouflage body patterns have been characterized spectrally in the laboratory but not in the field due to the challenges of dynamic natural light fields and the difficulty of using spectrophotometric instruments underwater. To assess cuttlefish color match in their natural habitats, we studied the spectral properties of S. officinalis and their backgrounds on the Aegean coast of Turkey using point-by-point in situ spectrometry. Fifteen spectrometry datasets were collected from seven cuttlefish; radiance spectra from animal body components and surrounding substrates were measured at depths shallower than 5 m. We quantified luminance and color contrast of cuttlefish components and background substrates in the eyes of hypothetical di- and trichromatic fish predators. Additionally, we converted radiance spectra to sRGB color space to simulate their in situ appearance to a human observer. Within the range of natural colors at our study site, cuttlefish closely matched the substrate spectra in a variety of body patterns. Theoretical calculations showed that this effect might be more pronounced at greater depths. We also showed that a non-biological method (“Spectral Angle Mapper”), commonly used for spectral shape similarity assessment in the field of remote sensing, shows moderate correlation to biological measures of color contrast. This performance is comparable to that of a traditional measure of spectral shape similarity, hue and chroma. This study is among the first to quantify color matching of camouflaged cuttlefish in the wild. 相似文献
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Lydia Beaudrot Matthew J. Struebig Erik Meijaard S. van Balen Simon Husson Andrew J. Marshall 《Oecologia》2013,173(3):1053-1062
Assessing the importance of deterministic processes in structuring ecological communities is a central focus of community ecology. Typically, community ecologists study a single taxonomic group, which precludes detection of potentially important biotic interactions between distantly related species, and inherently assumes competition is strongest between closely related species. We examined distribution patterns of vertebrate species across the island of Borneo in Southeast Asia to assess the extent to which inter-specific competition may have shaped ecological communities on the island and whether the intensity of inter-specific competition in present-day communities varies as a function of evolutionary relatedness. We investigated the relative extent of competition within and between species of primates, birds, bats and squirrels using species presence–absence and attribute data compiled for 21 forested sites across Borneo. We calculated for each species pair the checkerboard unit value (CU), a statistic that is often interpreted as indicating the importance of interspecific competition. The percentage of species pairs with significant CUs was lowest in within-taxon comparisons. Moreover, for invertebrate-eating species the percentage of significantly checkerboarded species pairs was highest in comparisons between primates and other taxa, particularly birds and squirrels. Our results are consistent with the interpretation that competitive interactions between distantly related species may have shaped the distribution of species and thus the composition of Bornean vertebrate communities. This research highlights the importance of taking into account the broad mammalian and avian communities in which species occur for understanding the factors that structure biodiversity. 相似文献
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Hengwei Zhang Chengwu Wu Lydia E. Matesic Xing Li Zhiyu Wang Brendan F. Boyce Lianping Xing 《The Journal of biological chemistry》2013,288(31):22359-22368
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Lydia R. Durant Spyridon Makris Cornelia Maaike Voorburg Jens Loebbermann Cecilia Johansson Peter J. M. Openshaw 《Journal of virology》2013,87(20):10946-10954
During viral infection, inflammation and recovery are tightly controlled by competing proinflammatory and regulatory immune pathways. Respiratory syncytial virus (RSV) is the leading global cause of infantile bronchiolitis, which is associated with recurrent wheeze and asthma diagnosis in later life. Th2-driven disease has been well described under some conditions for RSV-infected mice. In the present studies, we used the Foxp3DTR mice (which allow specific conditional depletion of Foxp3+ T cells) to investigate the functional effects of regulatory T cells (Tregs) during A2-strain RSV infection. Infected Treg-depleted mice lost significantly more weight than wild-type mice, indicating enhanced disease. This enhancement was characterized by increased cellularity in the bronchoalveolar lavage (BAL) fluid and notable lung eosinophilia not seen in control mice. This was accompanied by abundant CD4+ and CD8+ T cells exhibiting an activated phenotype and induction of interleukin 13 (IL-13)- and GATA3-expressing Th2-type CD4+ T cells that remained present in the airways even 14 days after infection. Therefore, Treg cells perform vital anti-inflammatory functions during RSV infection, suppressing pathogenic T cell responses and inhibiting lung eosinophilia. These findings provide additional evidence that dysregulation of normal immune responses to viral infection may contribute to severe RSV disease. 相似文献
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This article is part of a Special Issue “Puberty and Adolescence”. 相似文献
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Eike Gallmeier Dominik C. Bader Lydia Kriegl Sabina Berezowska Hendrik Seeliger Burkhard G?ke Thomas Kirchner Christiane Bruns Enrico N. De Toni 《PloS one》2013,8(2)