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991.
Juan F. Espínola‐Novelo M. Teresa Gonzlez Aldo S. Pacheco Jos L. Luque Marcelo E. Oliva 《Ecology letters》2020,23(4):631-641
Parasite communities are similar to free‐living communities; decay of similarity over geographic distance, theory of island biogeography, species–area relationships and nestedness have been documented in both communities. Ecological succession has been studied in free‐living communities but has rarely been examined in parasite communities. We use seriation with replication to test the hypothesis that succession of parasite community structure is deterministic, thus developing throughout consecutive changes along the fish ontogeny, via a seriated pattern. 12 306 marine fishes (95 species) were studied. In 40 species, a seriated pattern was detected; 25 had a tendency towards a seriated pattern, and for 31 species, succession was at random. Age‐classes for each host species explained deterministic successional patterns for whole parasite communities and ectoparasites. Richness and number of age‐classes explained this pattern for endoparasites. Seriated successional pattern was evident for parasite communities of long‐lived marine fish, indicating that parasite communities follow sequential changes over time, like many free‐living communities. 相似文献
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Yaoqi Li Peter B. Reich Bernhard Schmid Nawal Shrestha Xiao Feng Tong Lyu Brian S. Maitner Xiaoting Xu Yichao Li Dongting Zou Zheng‐Hong Tan Xiangyan Su Zhiyao Tang Qinghua Guo Xiaojuan Feng Brian J. Enquist Zhiheng Wang 《Ecology letters》2020,23(6):1003-1013
A key challenge in ecology is to understand the relationships between organismal traits and ecosystem processes. Here, with a novel dataset of leaf length and width for 10 480 woody dicots in China and 2374 in North America, we show that the variation in community mean leaf size is highly correlated with the variation in climate and ecosystem primary productivity, independent of plant life form. These relationships likely reflect how natural selection modifies leaf size across varying climates in conjunction with how climate influences canopy total leaf area. We find that the leaf size?primary productivity functions based on the Chinese dataset can predict productivity in North America and vice‐versa. In addition to advancing understanding of the relationship between a climate‐driven trait and ecosystem functioning, our findings suggest that leaf size can also be a promising tool in palaeoecology for scaling from fossil leaves to palaeo‐primary productivity of woody ecosystems. 相似文献
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Ambika Binesh Niranjali Devaraj Sivasitambaram Devaraj Halagowder 《Journal of biochemical and molecular toxicology》2020,34(3)
Antibiotics are essential in many life‐threatening diseases. On the other hand, improper use of antibiotics can be disastrous. Cell morphological changes were observed in the ciprofloxacin‐treated cells starting at 48 hours. Changes in cell morphology were continuously observed up to 14 days, which showed gradual morphological changes from monocyte to plaque‐like cells at day 12, and foam cell, which is an intermediate stage in atherosclerosis was observed at day 8, which was confirmed with Oil Red O staining. Flow cytometry data revealed that oxidized LDL (oxyLDL)‐induced cells showed 60.16% of CD64 (proinflammatory macrophage markers) and no expression of CD23 (anti‐inflammatory macrophage markers), whereas ciprofloxacin‐treated cells expressed 67.97% of CD64 and 13.78% of CD23. Chemokine antibody array analysis revealed that ciprofloxacin exposed cells showed a proinflammatory role (ENA78, Eotaxin1, Eotaxin2, IP‐10, MIG, MIP‐3β, SDF‐1β, TECK, CXCL16, and Fractalkine). Liquid chromatography with tandem mass spectrometry (LC‐MS/MS) revealed that myristic acid was incorporated into a protein with 68 kDa molecular mass in exposing oxyLDL‐induced monocytes with ciprofloxacin, which could be a reason for the observed foam cells and in vitro plaque formation. As myristic acid primes atherosclerosis, it is better to limit the intake of antibiotics like ciprofloxacin for common illness, specifically the high‐risk patients, which may contribute to atherosclerosis. 相似文献
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The aim of this study was to evaluate the dosimetric effect of continuous motion monitoring based localization (Calypso, Varian Medical Systems), gating and intrafraction motion correction in prostate SBRT. Delivered doses were modelled by reconstructing motion inclusive dose distributions for different localization strategies. Actually delivered dose (strategy A) utilized initial Calypso localization, CBCT and additional pre-treatment motion correction by kV-imaging and Calypso, and gating during the irradiation. The effect of gating was investigated by simulating non-gated treatments (strategy B). Additionally, non-gated and single image-guided (CBCT) localization was simulated (strategy C). A total of 308 fractions from 22 patients were reconstructed. The dosimetric effect was evaluated by comparing motion inclusive target and risk organ dose-volume parameters to planned values. Motion induced dose deficits were seen mainly in PTV and CTV to PTV margin regions, whereas CTV dose deficits were small in all strategies: mean ± SD difference in CTVD99% was –0.3 ± 0.4%, −0.4 ± 0.6% and –0.7 ± 1.2% in strategies A, B and C, respectively. Largest dose deficits were seen in individual fractions for strategy C (maximum dose reductions were −29.0% and –7.1% for PTVD95% and CTVD99%, respectively). The benefit of gating was minor, if additional motion correction was applied immediately prior to irradiation. Continuous motion monitoring based localization and motion correction ensured the target coverage and minimized the OAR exposure for every fraction and is recommended to use in prostate SBRT. The study is part of clinical trial NCT02319239. 相似文献