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111.
Katharina Haase Niels Kröger‐Lui Annemarie Pucci Arthur Schönhals Wolfgang Petrich 《Journal of biophotonics》2016,9(1-2):61-66
The speed and efficiency of quantum cascade laser‐based mid‐infrared microspectroscopy are demonstrated using two different model organisms as examples. For the slowly moving Amoeba proteus, a quantum cascade laser is tuned over the wavelength range of 7.6 µm to 8.6 µm (wavenumbers 1320 cm–1 and 1160 cm–1, respectively). The recording of a hyperspectral image takes 11.3 s whereby an average signal‐to‐noise ratio of 29 is achieved. The limits of time resolution are tested by imaging the fast moving Caenorhabditis elegans at a discrete wavenumber of 1265 cm–1. Mid‐infrared imaging is performed with the 640 × 480 pixel video graphics array (VGA) standard and at a full‐frame time resolution of 0.02 s (i.e. well above the most common frame rate standards). An average signal‐to‐noise ratio of 16 is obtained. To the best of our knowledge, these findings constitute the first mid‐infrared imaging of living organisms at VGA standard and video frame rate.
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Contemporary patterns of genetic diversity of cedrela fissilis offer insight into the shaping of seasonal forests in eastern South America 下载免费PDF全文
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Positive interactions between plants play a fundamental role in environments with extreme conditions, such as coastal sand dunes, where the establishment of many species is limited by high temperature, and low availability of water and nutrients in the soil. The ability to store water and enrich the soil with nutrients characterizes bromeliads as potential nurse plants for other species. This study aimed to analyze the potential of the bromeliad Vriesea friburgensis to act as a nurse plant, and to compare this interaction in coastal dunes in herbaceous versus scrub vegetation. The study was performed on Santa Catarina Island in Brazil. Juveniles of other species associated with V. friburgensis were collected within and under bromeliad tanks and on adjacent plots beside each bromeliad. The abundance, species richness and height of juveniles were recorded. We found that abundance and richness of Vf‐associated juveniles were lower than those Vf‐not associated, in herbaceous vegetation (negative interaction). However, the height of some shrubs species, like Eupatorium casarettoi and Tibouchina urvilleana, was greater when Vf‐associated (positive interaction). In scrub vegetation, the abundance and richness of juveniles were not significantly affected by V. friburgensis presence (neutral interaction). However, the height of some shrubs and trees species, like Clusia criuva, Eugenia catharinae, Myrsine parvifolia and Ocotea pulchella, was greater when Vf‐associated. Species composition associated with V. friburgensis differed from the assemblage in adjacent plots, indicating that some species interact more with nurse plants, whereas others fail to develop when associated with this bromeliad; the difference between groups in species composition was less evident in scrub vegetation areas. Clusia criuva was considered an indicator species for Vf‐associated juveniles in both vegetation types. Despite the fact that these tank bromeliads do not function as nurse plants for some species, there are others that seem to be favoured by this interaction. 相似文献
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正Despite our many advances in deconstructing and understanding cellular and biomolecular machineries,the homochirality of life remains an enigma.Since our earliest ancestors,the central dogma has operated solely on D-DNA 相似文献
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Beauty before age: landscape factors influence bird functional diversity in naturally regenerating fragments,but regeneration age does not 下载免费PDF全文
Davi F. C. Dias Milton C. Ribeiro Yan T. Felber Ana L. P. Cintra Natália S. de Souza Érica Hasui 《Restoration Ecology》2016,24(2):259-270
Effective ecological restoration actions should be able to recover ecosystem processes that influence community development in the long term. However, there is scarce information on how landscape factors promote or accelerate fauna recovery. We used a landscape framework to evaluate how functional groups respond to natural regeneration in a highly fragmented region of Atlantic Forest. Using bird functional groups sampled in 15 regenerating forest fragments, we built and ranked models using a model selection approach to test the relative effect of landscape variables on each group. Our results showed that bird community recovery is not determined by the duration of the regeneration process (i.e. forest age), but by how the species responds to the landscape context. Functional diversity and the abundance of the functional groups were mainly related to composition metrics, whereas the functional metric affected only specific groups. Our findings highlight the importance of considering the landscape level to ensure both the colonization of fauna and the restoration of ecological functions. 相似文献
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Journal of Plant Research - The development and functioning of the nitrogen fixing symbiosis between legume plants and soil bacteria collectively called rhizobia requires continuous chemical... 相似文献