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The Cryogenian Sturtian and Marinoan Snowball Earth glaciations bracket a nonglacial interval during which Demosponge and green-algal biomarkers first appear. To understand the relationships between environmental perturbations and early animal evolution, we measured sulfur and mercury isotopes from the Datangpo Formation from South China. Hg enrichment with positive Δ199Hg excursion suggests enhanced volcanism, potentially due to depressurization of terrestrial magma chambers during deglaciation. A thick stratigraphic interval of negative Δ33Spy indicates that the nonglacial interlude was characterized by low but rising sulfate levels. Model results reveal a mechanism to produce the Δ33S anomalies down to -0.284 through Rayleigh distillation. We propose that extreme temperatures and anoxia contributed to the apparent delay in green algal production in the aftermath of the Sturtian glaciation and the subsequent reoxygenation of the iron-rich and sulfate-depleted ocean paved the way for evolution of animals.
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Organic small-molecule fluorescent chromophores have become essential to modern chemical, biological, and materials related investigations. Herein, a straightforward synthesis and subsequent borylation were presented to form a novel family of bisBF2-anchoring acyl-pyridinylhydrazine, which we named BOAPH. The chromophore enjoys outstanding structural diversities owing to varied acyl chlorides and N-heteroarenylhydrazides. These resultant BOAPH dyes are confirmed by NMR, HRMS, and single-crystal X-ray structure analysis. Their spectroscopic properties were studied, and most of the strong absorbance and bright fluorescence with maximum wavelengths centered in the range of 400 and 650 nm. More importantly, they exhibit promising fluorescence quantum yields up to 0.79 in solution and solid states, good photostability, and large Stokes shifts. Furthermore, a respective BOAPH dye with a para-dimethylaminophenyl group exhibited the interesting ability of ultrafast staining and two-photon imaging, which can specifically label lipid droplets of living cells immediately without the need for incubation.
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Colorantes Fluorescentes , Fotones , Fluorescencia , IonóforosRESUMEN
BACKGROUND: As the largest group of mammalian species, which are also widely distributed all over the world, rodents are the natural reservoirs for many diverse zoonotic viruses. A comprehensive understanding of the core virome of diverse rodents should therefore assist in efforts to reduce the risk of future emergence or re-emergence of rodent-borne zoonotic pathogens. RESULTS: This study aimed to describe the viral range that could be detected in the lungs of rodents from Mainland Southeast Asia. Lung samples were collected from 3284 rodents and insectivores of the orders Rodentia, Scandentia, and Eulipotyphla in eighteen provinces of Thailand, Lao PDR, and Cambodia throughout 2006-2018. Meta-transcriptomic analysis was used to outline the unique spectral characteristics of the mammalian viruses within these lungs and the ecological and genetic imprints of the novel viruses. Many mammalian- or arthropod-related viruses from distinct evolutionary lineages were reported for the first time in these species, and viruses related to known pathogens were characterized for their genomic and evolutionary characteristics, host species, and locations. CONCLUSIONS: These results expand our understanding of the core viromes of rodents and insectivores from Mainland Southeast Asia and suggest that a high diversity of viruses remains to be found in rodent species of this area. These findings, combined with our previous virome data from China, increase our knowledge of the viral community in wildlife and arthropod vectors in emerging disease hotspots of East and Southeast Asia. Video abstract.
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Pulmón/virología , ARN Viral/análisis , Roedores/virología , Viroma/genética , Animales , Asia Sudoriental , Insectos/virologíaRESUMEN
A new family of pyrrolyl-acylhydrazones anchored with two BF2 units, named BOAPY, have been developed as BODIPY-like and unsymmetrical bis(BF2) chromophores via a simple one-pot reaction. The easily accessible scaffold enjoys excellent diversity due to the structural versatilities of 2-formylpyrroles and acylhydrazines. BOAPYs exhibit good molar absorption coefficients, large Stokes shifts, and excellent chemical stability. More importantly, most of them display excellent fluorescence quantum yields both in solution and the solid state (up to 0.88 and 0.64, respectively).
RESUMEN
A fast and mild synthesis method of highly crystalline CdTe nanorods (NRs) was developed by adding europium nitrate hexahydrate to an aqueous solution of CdTe nanocrystals (NCs) at room temperature within 30 min. It was suggested that strong coordination strength of Eu(III) decreases zeta potential, thereby accelerates aggregation of NCs, and favors the transformation process from NCs to NRs. The oriented attachment of aggregated particles was suggested as a major path for the formation of highly crystalline NRs under experimental conditions. The proposed extremely fast room-temperature methodology opens up novel pathways for the synthesis of one-dimensional (1D) semiconductor nanostructures with high crystallinity, which would become potential candidates for many practical applications such as photovoltaics, circuit design and fabrication of functional architectures.