The phylogenetic affinities of the fern genus Aenigmopteris have been the subject of considerable disagreement, but until now, no molecular data were available from the genus. Based on the analysis of three chloroplast DNA regions (rbcL, rps16-matK, and trnL-F) we demonstrate that Aenigmopteris dubia (the type species of the genus) and A. elegans are closely related and deeply imbedded in Tectaria. The other three species of genus are morphologically very similar; we therefore transfer all five known species into Tectaria. Detailed morphological comparison further shows that previously proposed diagnostic characters of Aenigmopteris fall within the range of variation of a broadly circumscribed Tectaria.
Background. Quaternary structures of proteins are closely relevant to gene regulation, signal transduction, and many other biological functions of proteins. In the current study, a new method based on protein-conserved motif composition in block format for feature extraction is proposed, which is termed block composition. Results. The protein quaternary assembly states prediction system which combines blocks with functional domain composition, called QuaBingo, is constructed by three layers of classifiers that can categorize quaternary structural attributes of monomer, homooligomer, and heterooligomer. The building of the first layer classifier uses support vector machines (SVM) based on blocks and functional domains of proteins, and the second layer SVM was utilized to process the outputs of the first layer. Finally, the result is determined by the Random Forest of the third layer. We compared the effectiveness of the combination of block composition, functional domain composition, and pseudoamino acid composition of the model. In the 11 kinds of functional protein families, QuaBingo is 23% of Matthews Correlation Coefficient (MCC) higher than the existing prediction system. The results also revealed the biological characterization of the top five block compositions. Conclusions. QuaBingo provides better predictive ability for predicting the quaternary structural attributes of proteins.
Antibiotic sulfamethoxazole (SMX) has been commonly found in various water matrices, therefore effective decontamination method is urgently needed. Metal-free pristine coconut-shell-derived biochar (CSBC), synthesized by thermochemical conversion at 700 °C, was used for activating peroxymonosulfate (PMS), an oxidant, to degrade SMX, a sulfonamide antibiotic, in water. SMX degradation, maximized at 0.05 mM concentration, was 85% in 30 min at pH 5.0 in the presence of 150 mg L-1 of CSBC. Remarkably, SMX removal reached 99% in a chloride-rich CSBC/PMS system. SMX degradation was mainly attributed to the role of CSBC in enhancing PMS activation to produce combined radical (SO4•-/HO•) and nonradical (1O2) reaction pathways. The most abundant genus in the CSBC/PMS system was Methylotenera, which belonged to the Proteobacteria phylum. Thus, from a perspective of biowaste-to-resource recycling and circular bioeconomy view point, CSBC is a potential catalytic activator of PMS for the removal of sulfonamide antibiotics from aqueous environments.
In this study, biochar produced from sunflower seeds husk was activated through ZnCl2 to support the NiCo2O4 nanoparticles (NiCo2O4@ZSF) in catalytic activation of peroxymonosulfate (PMS) toward tetracycline (TC) removal from aqueous solution. The good dispersion of NiCo2O4 NPs on the ZSF surface provided sufficient active sites and abundant functional groups for the adsorption and catalytic reaction. The NiCo2O4@ZSF activating PMS showed high removal efficiency up to 99% after 30 min under optimal condition ([NiCo2O4@ZSF] = 25 mg L-1, [PMS] = 0.04 mM, [TC] = 0.02 mM and pH = 7). The catalyst also exhibited good adsorption performance with a maximum adsorption capacity of 322.58 mg g-1. Sulfate radicals (SO4•-), superoxide radical (O2•-), and singlet oxygen (1O2) played a decisive role in the NiCo2O4@ZSF/PMS system. In conclusion, our research elucidated the production of highly efficient carbon-based catalysts for environmental remediation, and also emphasized the potential application of NiCo2O4 doped biochar.
Although chiral semiconductors have shown promising progress in direct circularly polarized light (CPL) detection and emission, they still face potential challenges. A chirality-switching mechanism or approach integrating two enantiomers is needed to discriminate the handedness of a given CPL; additionally, a large material volume is required for sufficient chiroptical interaction. These two requirements pose significant obstacles to the simplification and miniaturization of the devices. Here, w e demonstrate room-temperature chiral polaritons fulfilling dual-handedness functions and exhibiting a more-than-two-order enhancement of the chiroptical signal, by embedding a 40-nm-thick perovskite film with a two-dimensional chiroptical effect into a Fabry-Perot cavity. By mixing chiral perovskites with different crystal structures, w e accomplish a pronounced two-dimensional chiroptical effect in the perovskite film, featured by an inverted chiroptical response for counter-propagating CPL. This inversion behavior matches the photonic handedness switch during CPL circulation in the Fabry-Perot cavity, thus harvesting giant enhancement of the chiroptical response. Furthermore, affected by the unique quarter-wave-plate effects, the polariton emission achieves a chiral dissymmetry of ±4% (for the emission from the front and the back sides). The room-temperature polaritons with the strong dissymmetric chiroptical interaction should have implications on a fundamental level and future on-chip applications for bio-molecule analysis and quantum computing. This article is protected by copyright. All rights reserved.
New Guinea is the world's largest tropical island and has fascinated naturalists for centuries1,2. Home to some of the best-preserved ecosystems on the planet3 and to intact ecological gradients-from mangroves to tropical alpine grasslands-that are unmatched in the Asia-Pacific region4,5, it is a globally recognized centre of biological and cultural diversity6,7. So far, however, there has been no attempt to critically catalogue the entire vascular plant diversity of New Guinea. Here we present the first, to our knowledge, expert-verified checklist of the vascular plants of mainland New Guinea and surrounding islands. Our publicly available checklist includes 13,634 species (68% endemic), 1,742 genera and 264 families-suggesting that New Guinea is the most floristically diverse island in the world. Expert knowledge is essential for building checklists in the digital era: reliance on online taxonomic resources alone would have inflated species counts by 22%. Species discovery shows no sign of levelling off, and we discuss steps to accelerate botanical research in the 'Last Unknown'8.