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691.
Changyu Zhu Weiwei Liu Xinghao Li Yusen Xu Hamed A. El-Serehy Saleh A. Al-Farraj Honggang Ma Thorsten Stoeck Zhenzhen Yi 《Environmental microbiology》2021,23(8):4778-4796
Microeukaryotes play key ecological roles in the microbial web of aquatic ecosystems. However, large knowledge gaps urgently need to be filled regarding the biogeography with associated shaping mechanisms and co-occurrence patterns of microeukaryotes under freshwater-saltwater gradients, especially true in tropical regions. Here, we investigated microeukaryotes of six mixed freshwater-saltwater regions in the Pearl River Estuary and surrounding coasts in southern China, with salinity ranging 0.1–32.0% and distances spanned up to 500 km, using molecular ecological methods. Results indicate that the biogeography of abundant and rare microeukaryotic communities was similar, both their co-occurrence patterns and biogeographical patterns were driven by deterministic and stochastic processes. The environmental factors with higher selective pressure than dispersal limitation meant that the role of deterministic process in structuring communities was more significant than that of stochastic process, and salinity played important role in structuring both microeukaryotic communities and networks. The abundant communities had stronger influence on entire microeukaryotic communities and seemed to be more sensitive to environmental changes than their rare counterparts, while rare ones had stronger interspecific relationships. Finally, the geographic scale and environmental gradients of study regions should firstly be clarified in future research on the ecological processes of microeukaryotes before conclusions are drawn. 相似文献
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Basic strategies and recent developments for the enhancement of the sensory performance of nanostructures in the electroanalysis of pharmaceuticals are reviewed. A discussion of the properties of nanostructures and their application as modified electrodes for drug assays is presented. The electrocatalytic effect of nanostructured materials and their application in determining low levels of drugs in pharmaceutical forms and biofluids are discussed. 相似文献
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Hansen Ulf-Peter; Moldaenke Christian; Tabrizi Hamed; Ramm Daniela 《Plant & cell physiology》1993,34(5):681-695
The light-induced changes of plasmalemma potential and of chlorophyllfluorescence were compared with changes induced by the modulationof O2- or CO2-concentration. The fast depolarisation of plasmalemmapotential upon illumination as labeled by the time-constant 相似文献
699.
Palladium nanoparticles were potentiostatically electrodeposited on a gold surface at a highly negative potential. The nanostructure, as a transducer, was utilized to immobilize a Brucella-specific probe and the process of immobilization and hybridization was detected by electrochemical methods. The proposed method for detection of the complementary sequence and a non-complementary sequence was applied. The fabricated genosensor was evaluated for the assay of the bacteria in the cultured and human samples with and without PCR. The genosensor could detect the complementary sequence with a sensitivity of 0.02 μA dm3 mol−1, a linear concentration range of 1.0 × 10−12 to 1.0 × 10−19 mol dm−3, and a detection limit of 2.7 × 10−20 mol dm−3. 相似文献
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Silvia Franz Hamed Arab Gian Luca Chiarello Massimiliano Bestetti Elena Selli 《Liver Transplantation》2020,10(23)
The fast, single‐step and easily scalable production by plasma electrolytic oxidation (PEO) of large area TiO2 electrodes with excellent photoactivity in water splitting under simulated solar light is systematically investigated here. In particular, the effects that the cell voltage (100–180 V) and the processing time (0.5–15 min) have on the electrode properties are studied. The PEO‐produced oxide layers are porous, the predominant crystalline structure shifting from anatase, to an anatase‐rutile mixture, and finally to rutile by rising the cell voltage. The electrodes show a double‐layered structure, with a more compact layer at the interface with the titanium substrate and a thick porous layer on the external surface. The photocurrent density versus wavelength reflects the phase composition, with a maximum incident photon‐to‐current efficiency of 90% at 320 nm. The highest H2 production rate is attained with the mixed anatase‐rutile electrode prepared by 300 s‐long PEO at 150 V. 相似文献