Phosphorous doped carbon dots (P-CDs) are prepared by a one-step hydrothermal method. The phenomenon of aggregation induced red shift emission (AIRSE) is observed in the obtained P-CDs. The emission ...wavelength of a P-CD solution can be tuned in the range from 455 nm to 595 nm by changing the solution concentration.
Sodium-ion batteries (SIBs) and potassium-ion batteries (KIBs) are greatly potential candidates for large-scale renewable energy storage. However, developing highly efficient anode materials for the ...relatively larger radius of Na+ and K+ ions is still a hot issue. Herein, we report spherical nanoflowers of vanadium disulfide (VS2) with thin petals of 15 nm and high purity of crystallinity, synthesized by one-pot solvothermal method using propylene glycol as solvent without any growth-directing surfactants. Results demonstrate that this spherical nanoflower structure provides a stable framework for Na+/K+ insertion/extraction, wherein, SNF-VS2 not only shows a reversible charge capacity of 329 mAh/g at 0.2 A/g with an initial coulombic efficiency (ICE) of 88.52% for sodium ion storage, but also delivers a reversible charge capacity of 383 mAh/g at 25 mA/g, owning an ICE of 74.09% for potassium ion storage. The high capacity and outstanding ICE make the spherical VS2 nanoflowers ranking among the most effective transition metal dichalcogenide based anode materials and strongly indicate their promising usability for practical SIB and KIB applications. And the outperforming Na+/K+ storage performance is largely due to the abundant interface area with electrolyte and the short ion diffusion paths formed by their ordered flower-like structure.
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•Spherical nanoflower like VS2 was synthesized using a non-template strategy.•The VS2 exhibited high capacities, reversibility and excellent cyclability for Na+/K+ storage.•The unique nanoflower structure provides a more efficient Na+/K+ diffusion path than that of stacked structure.
The conventional hybridization chain reaction (HCR)-based electrochemical biosensors usually require the immobilization of probes on the electrode surface. This will limit the applications of ...biosensors due to the shortcomings of complex immobilization processes and low HCR efficiency. In this work, we proposed astrategy for the design of HCR-based electrochemical biosensors by integrating the advantages of homogeneous reaction and heterogeneous detection. Specifically, the targets triggered the autonomous cross-opening and hybridization oftwobiotin-labeled hairpin probes to form long-nicked dsDNA polymers. The HCR products with many biotin tags were then captured by a streptavidin-covered electrode, thus allowing for the attachment of streptavidin-conjugated signal reporters through streptavidin-biotin interactions. By employing DNA and microRNA-21 as the model targets and glucose oxidase as the signal reporter, the analytical performances of the HCR-based electrochemical biosensors were investigated. The detection limits of this method were found to be 0.6 fM and 1 fM for DNA and microRNA-21, respectively. The proposed strategy exhibited good reliability for target analysis in serum and cellular lysates. The strategy can be used to develop various HCR-based biosensors for a wide range of applications because sequence-specific oligonucleotides exhibit high binding affinity to a series of targets. In light of the high stability and commercial availability of streptavidin-modified materials, the strategy can be used for the design of different biosensors by changing the signal reporter and/or the sequence of hairpin probes.
Accurately identifying the supply and demand of ecosystem services at multiple scales and determining the factors that influence the supply–demand relationship are crucial for guiding the sustainable ...management and restoration of regional ecosystem services. In view of this, we quantified the supply and demand of five ecosystem services at multiple scales in the Qinling–Daba Mountain area based on spatial and statistical data, exploring the relationships between the supply and demand for ecosystem services at multiple scales and examining the mechanisms by which factors like natural and human activities affect the evolution of the supply and demand patterns of these services. The results show that (1) there was no risk associated with supply and demand of ESs in the Qinling–Daba Mountain area, and numerous ESs were in excess. The impact of ES supply and demand became increasingly clear as the spatial scale was increased. (2) Under multiple spatial scales, the relationship between the supply and demand of ESs will change. At the mesoscale, the relationship between ES supply and demand was the most significant, whereas at the macroscale, the relationship between ES demands was the most significant. (3) Cultivated land, grass land, and forest land are the key land use categories in regional ecosystem service hotspots, providing richer ecosystem service functions for the region. (4) Precipitation and NDVI are the main elements determining the supply of ecosystem services. While GDP and population density have a significant impact on the demand for ecosystem services, natural causes are primarily responsible for trade-offs in ecosystem services. This study aims to evaluate the supply–demand relationship and driving factors of multiple scale in the Qinling–Daba Mountains, providing a scientific basis for the sustainable management of ecosystems in the region.
The impact of endothelial cell-specific molecule 1 (ESM1) on the initiation and progression of diverse cancers has been extensively studied, yet its regulatory mechanisms in relation to cervical ...cancer remain insufficiently understood. Through bioinformatics analysis, we revealed that ESM1 was highly expressed in cervical squamous cell carcinoma and endocervical adenocarcinoma (CESC) and correlated with dismal clinicopathological features. The activation of ESM1 is facilitated by the presence of oncogenic HPV E6 and E7. HPV E6 and E7 enhance the expression of ESM1 by diminishing the levels of miR-205-5p, which specifically targets the 3′ untranslated region of ESM1 mRNA. In addition, we demonstrated that ESM1 facilitates aerobic glycolysis of cervical cancer cells via the Akt/mTOR pathway. Suppression of ESM1 led to a reduction in the expression of HIF-1α and multiple glycolytic enzymes. Taken together, our findings provide insights into the mechanisms by which HPV infections regulate oncogenes, thereby contributing to cervical carcinogenesis.
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•ESM1 is highly expressed in CESC and can serve as an independent prognostic marker•Oncogenic HPV E6 and E7 upregulate ESM1 expression via the inhibition of miR-205-5p•ESM1 promotes aerobic glycolysis through the Akt/mTOR pathway
Molecular biology; Cell biology; Cancer
A human host exploits stresses such as acidic/alkaline pH, antifungal drugs, and reactive oxygen species to kill microbial pathogens such as the fungus Aspergillus fumigatus. However, A. fumigatus is ...resistant to these stresses
. Therefore, what accounts for the potent antifungal activity of the human host? In this observation, we show that simultaneous exposure to acidic pH and oxidative stresses is much more potent than the individual stresses themselves and that this combinatorial stress kills A. fumigatus synergistically
. Interestingly, A. fumigatus is resistant to the combination of alkaline pH and oxidative stress. Quantitative real-time PCR analyses showed that acidic/alkaline pH stress can mediate oxidative stress responses in A. fumigatus by regulating the expression of catalase-encoding genes. We further show that A. fumigatus is sensitive to the combination of acidic/alkaline stress and azole drug stress. Transcriptome analysis revealed that the sensitivity of A. fumigatus to azole drugs under acidic/alkaline conditions may be related to changes in genetic stability, sphingolipid metabolism, lipid metabolism, and amino acid metabolism. Collectively, our findings suggest that combinatorial stress represents a powerful fungicidal mechanism employed by hosts against pathogens, which suggests novel approaches to potentiate antifungal therapy.
The human host combats fungal infections via phagocytic cells that recognize and kill fungal pathogens. Immune cells combat Aspergillus fumigatus infections with a potent mixture of chemicals, including reactive oxygen species, acidic/alkaline stress, and antifungal drugs. However, A. fumigatus is relatively resistant to these stresses
. In this observation, we show that it is the combination of acidic/alkaline pH and oxidative or azole stress that kills A. fumigatus so effectively, and we define the molecular mechanisms that underlie this potency. Our findings suggest that combinatorial stress is a powerful fungicidal mechanism employed by hosts, which suggests novel approaches to potentiate antifungal therapy. This study provides a platform for future studies that will address the combinatorial impacts of various environmental stresses on A. fumigatus and other pathogenic microbes.
Bovine viral diarrhea virus (BVDV) is an important livestock viral pathogen responsible for causing significant economic losses. The emerging and novel BVDV isolates are clinically and biologically ...important, as there are highly antigenic diverse and pathogenic differences among BVDV genotypes. However, no study has yet compared the virulence of predominant genotype isolates (BVDV-1a, 1b, and 1m) in China and the emerging genotype isolate BVDV-1v. The serological relationship among these genotypes has not yet been described. In this study, we isolated three BVDV isolates from calves with severe diarrhea, characterized as BVDV-1a, 1m, and novel 1v, based on multiple genomic regions including 5-untranslated region (5′-UTR), Npro, and E2 and the phylogenetic analysis of nearly complete genomes. For the novel genotype, genetic variation analysis of the E2 protein of the BVDV-1v HB-03 strain indicates multiple amino acid mutation sites, including potential host cell-binding sites and neutralizing epitopes. Recombination analysis of the BVDV-1v HB-03 strain hinted at the possible occurrence of cross-genotypes (among 1m, 1o, and 1q) and cross-geographical region transmission events. To compare the pathogenic characters and virulence among these BVDV-1 genotypes, newborn calves uninfected with common pathogens were infected intranasally with BVDV isolates. The calves infected with the three genotype isolates show different symptom severities (diarrhea, fever, slowing weight gain, virus shedding, leukopenia, viremia, and immune-related tissue damage). In addition, these infected calves also showed bovine respiratory disease complexes (BRDCs), such as nasal discharge, coughing, abnormal breathing, and lung damage. Based on assessing different parameters, BVDV-1m HB-01 is identified as a highly virulent strain, and BVDV-1a HN-03 and BVDV-1v HB-03 are both identified as moderately virulent strains. Furthermore, the cross-neutralization test demonstrated the antigenic diversity among these Chinese genotypes (1a, 1m, and 1v). Our findings illustrated the genetic evolution characteristics of the emerging genotype and the pathogenic mechanism and antigenic diversity of different genotype strains, These findings also provided an excellent vaccine candidate strain and a suitable BVDV challenge strain for the comprehensive prevention and control of BVDV.
Karst is a widespread ecosystem with properties that affect the microbial activity and storage and cycling of soil organic carbon. The mechanisms underlying microbial resource availability in karst, ...which limit the microbial growth and activity in soil aggregates, remain largely unknown. We assessed the microbial resource limitations using exoenzymatic stoichiometry and key extracellular enzyme activities in bulk soil and aggregates in karst and non-karst forest soils. Soil organic carbon, total nitrogen, and microbial biomass carbon and nitrogen were significantly higher in bulk soil and the aggregate fractions in karst forests. However, the microbial biomass accumulation was higher in finer aggregates than in macroaggregate fractions. This may be attributed to the surface area of finer aggregates that increase the microbial C accumulation. In karst forests, the activity of extracellular enzymes β-d-glucosidase, β-N-acetylglucosaminidase, α-glucosidase, and α-d-1,4-cellobiosidase was two to three times higher in microaggregates (0.053–0.25 mm) and mineral fractions (<0.053 mm) than in macroaggregates. This coincided with the distribution of microbial biomass carbon and phosphorus in finer aggregate fractions. The microorganisms in bulk soil and aggregates in karst forests were largely co-limited by carbon and phosphorus and rarely by nitrogen and only by phosphorus in non-karst soils. The microbial phosphorus limitation in non-karst soils was alleviated in finer soil aggregates, while these fractions reflected slightly higher. microbial C limitations than bulk and other aggregates in karst forests. The patterns of microbial resource limitations in the bulk and aggregate fractions in karst ecosystems reflected the regulation of enzyme activity and soil organic carbon accumulation in finer aggregate fractions but not in other aggregates.
Heteroatom doped carbon materials have been emerging as active materials for electrochemical energy generation and storage. The activity of such carbon materials is strongly depended the specific ...molecular structure of selected precursors and their synthetic strategy. Herein, we report an efficient bifunctional N, S co-doped carbon nanosphere(NS/C) via pyrolysis of poly (2,6-Diaminopyridine) spheres as precursor for the first time, in which 2,6-Diaminopyridine was polymerized in water using ammonium persulfate as both initiator and sulfur source in the absence of templates and surfactants. The resultant NS/C exhibits uniformly spherical structure filled with hierarchical pores, outstanding electronic conductivity and highly effective doping content of N(4.02 at%) and S(0.87 at%) elements. Electrochemical measurements demonstrate that the NS/C not only exhibits outstanding specific capacitance of 800 F/g in 6.0 M KOH and 710 F/g in 1.0 M H2SO4, but also displays excellent catalytic performance for oxygen reduction reaction (ORR) with the onset potential at 1.01 V vs RHE and the half-wave potential at 0.85 V vs RHE in 0.1 M KOH, outperforming the activity of carbon materials previously reported. The superior electrochemical properties of NS/C is directly attributed to the synergetic effect of N,S co-doping and its excellent conductivity, accessibility, high specific surface area as well as hierarchical pore structure.
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•N, S-co-doped carbon nanospheres were synthesized via pyrolysis of the self-polymerized compound of 2,6-Diaminopyridine.•The N, S-co-doped carbon nanospheres exhibit high charge storage capacity with high specific capacitance and highly efficient ORR catalytic performance.•Heterocyclic polymers with meta-amino group can be used to synthesize heteroatom doped carbon nanospheres by this method.
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