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71.
Although critically important, the link between animal life histories and ecosystem energetics is seldom explored. In the
pursuit of ecological simplification, ecosystem properties are typically described by models based on static counts, where
organisms are aggregated into trophic- or size-based groups. Consequently, output is often based on an assumption that larger
group biomass equals greater energetic contribution. Here, we modelled the individual growth of over 58,000 fishes from 74
genera within a coral reef ecosystem to investigate the role and importance of taxon-specific life histories to the division,
spatial distribution and relative contribution of biomass production within 14 coral reef fish families. Rank changes among
families in standing biomass to biomass production indicated that small cryptic families (e.g. Gobiidae and Blenniidae) exhibit
collective growth potentials equal to or exceeding those of many other common families composed of individuals with body-sizes
1–3 orders of magnitude larger. Remaining at high risk of predation throughout their lives as a consequence of their small
size, these cryptic fishes also provide a constant food resource and supply of reproductive energy to coral reefs throughout
the year. Enhanced further by the strength and diversity of their trophic relationships within food webs, the highly productive
nature of these small cryptic fishes suggests they make a substantial contribution to the flow of energy in coral reef ecosystems
via predatory pathways. It appears that life histories leave a strong imprint on ecosystem energy fluxes and illustrate the
importance of incorporating taxon-specific features when assigning values to key ecosystem processes.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
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Millan DS Ballard SA Chunn S Dybowski JA Fulton CK Glossop PA Guillabert E Hewson CA Jones RM Lamb DJ Napier CM Payne-Cook TA Renery ER Selby MD Tutt MF Yeadon M 《Bioorganic & medicinal chemistry letters》2011,21(19):5826-5830
In this Letter we present data for a novel series of ICS for the treatment of asthma. 'Inhalation by design' principles have been applied to a series of highly potent steroidal GR agonists, with a focus on optimising the potential therapeutic index in human. Pharmacokinetic properties were tuned with high intrinsic clearance and low oral bioavailability in mind, to minimise systemic exposure and reduce systemically driven adverse events. High CYP mediated clearance as well as glucuronidation were targeted to achieve high intrinsic clearance coupled with multiple routes of clearance to minimise drug-drug interactions. Furthermore, pharmaceutical properties such as stability, crystallinity and solubility were considered to ensure compatibility with a dry powder inhaler. This work culminated in the identification of the clinical candidate 15, which demonstrates preclinically the desired efficacy and safety profiles confirming its potential as an inhaled agent for the treatment of asthma. 相似文献
74.
Carotenoid biomarkers as an imperfect reflection of the anoxygenic phototrophic community in meromictic Fayetteville Green Lake 总被引:1,自引:0,他引:1
Organic biomarkers in marine sedimentary rocks hold important clues about the early history of Earth's surface environment. The chemical relicts of carotenoids from anoxygenic sulfur bacteria are of particular interest to geoscientists because of their potential to signal episodes of marine photic-zone euxinia such as those proposed for extended periods in the Proterozoic as well as brief intervals during the Phanerozoic. It is therefore critical to constrain the environmental and physiological factors that influence carotenoid production and preservation in modern environments. Here, we present the results of coupled pigment and nucleic acid clone library analyses from planktonic and benthic samples collected from a microbially dominated meromictic lake, Fayetteville Green Lake (New York). Purple sulfur bacteria (PSB) are abundant and diverse both in the water column at the chemocline and in benthic mats below oxygenated shallow waters, with different PSB species inhabiting the two environments. Okenone (from PSB) is an abundant carotenoid in both the chemocline waters and in benthic mats. Green sulfur bacteria and their primary pigment Bchl e are also represented in and below the chemocline. However, the water column and sediments are devoid of the green sulfur bacteria carotenoid isorenieratene. The unexpected absence of isorenieratene and apparent benthic production of okenone provide strong rationale for continued exploration of the microbial ecology of biomarker production in modern euxinic environments. 相似文献
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Fulton Risdon 《CMAJ》1931,25(5):563-565
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Venkitaramani DV Fulton DB Andreotti AH Johansen KM Johansen J 《Protein science : a publication of the Protein Society》2005,14(7):1894-1901
Calsensin is an EF-hand calcium-binding protein expressed by a subset of peripheral sensory neurons that fasciculate into a single tract in the leech central nervous system. Calsensin is a 9-kD protein with two EF-hand calcium-binding motifs. Using multidimensional NMR spectroscopy we have determined the solution structure and backbone dynamics of calcium-bound Calsensin. Calsensin consists of four helices forming a unicornate-type four-helix bundle. The residues in the third helix undergo slow conformational exchange indicating that the motion of this helix is associated with calciumbinding. The backbone dynamics of the protein as measured by (15)N relaxation rates and heteronuclear NOEs correlate well with the three-dimensional structure. Furthermore, comparison of the structure of Calsensin with other members of the EF-hand calcium-binding protein family provides insight into plausible mechanisms of calcium and target protein binding. 相似文献