Search

The occurrence of classical swine fever (CSF) poses a significant threat to the global swine industry. Developing an effective and safe vaccine is crucial for preventing and controlling CSF. Here, we constructed self-assembled ferritin nanoparticles fused with the classical swine fever virus (CSFV) E2 protein and a derived B cell epitope (Fe-E2B) using a baculovirus expression system (BVES), demonstrating enhanced immunogenicity. Furthermore, we provide a detailed evaluation of the immunological efficacy of the FeE2B in rabbits. The results showed that robust and sustained antibody responses were detected in rabbits immunized with the Fe-E2B nanoparticle vaccine, comparable to those elicited by commercially available vaccines. Additionally, we demonstrated that the vaccine effectively activated crucial immune factors IFN-γ and IL-4 in vivo, increasing their levels by 1.41-fold and 1.39-fold, respectively. Immunization with Fe-E2B enabled rabbits to avoid viremia and stereotypic fever after CSFV challenge. In conclusion, this study highlights the potential of ferritin nanoparticles as antigen-presenting carriers to induce robust immune responses, proposing a candidate vaccine strategy for the prevention and control of CSF. [ABSTRACT FROM AUTHOR]

Used fly ash as raw material, it was modified by acid, alkali and high temperature to produce modified fly ash adsorbent, sulfuric acid modified fly ash adsorbent, sodium hydroxide modified fly ash adsorbent and high temperature modified fly ash adsorbent. In this paper, the effects of adsorbent dosage, adsorbent adsorption time, initial dye concentration, wastewater pH and temperature on dye adsorption were studied. The results showed that: the acid modified fly ash adsorbent had a good treatment effect on the dye; when the dosage of fly ash was 1.00 g, the adsorption time was 90 min, the pH of wastewater was 4, and the temperature was 45 °C, the decolorization rate of 60 mg/L methyl orange dye can reached more than 70%; when the dosage of fly ash was 0.20 g, the adsorption time was 60 min, the pH of wastewater was 3, and the temperature was 35 °C, the decolorization rate of 20 mg/L methyl orange dye can be achieved. The decolorization rate of Congo red can reached more than 80%.

With the development of society, pollution accidents occur more frequently, and the effects of toxic substances containing silver on human health and environment are increasingly extensive. Therefore, the real-time on-site monitoring of silver ions is urgently needed. Based on the catalase-like properties of graphene/nano-platinum composites and the coupling effect between Pt and Ag+, a simple, unlabeled colorimetric sensing method is proposed to achieve the quantitative detection of Ag+. Under optimal conditions, the detection range of Ag+ by this colorimetric sensing method is 0.5–1000 μM, and the detection limit is 0.5 μM, which is lower than the previously reported detection limit of unlabeled Ag+ colorimetric sensing method, showing higher sensitivity and detection range. Under the same conditions, the sensor has almost no response to interference ions, showing good specific recognition ability. In addition, the colorimetric sensing method can be used to detect Ag+ in actual water samples, serving as a new paradigm for visual detection of Ag+. [ABSTRACT FROM AUTHOR]

Structural reliability analysis is a crucial task in structural safety analysis. Owing to insufficient data information, traditional probabilistic methods do not accurately quantify input or output variables and the resultant assessment of structural reliability. Considering the development of engineering technology, a quantitative model of uncertainty based on improbability method is urgently needed. Herein, a novel nonprobabilistic Bayesian-inference-based interval uncertainty quantification model is developed with a user-specified credibility level. On the contrary, limited samples are introduced to update the bounds of the interval, and the conservativeness is decreased compared to the traditional unbiased interval estimation based on uniform distribution. Moreover, it can provide more conservative quantification than the extreme values-based interval model. Consequently, two examples are implemented to demonstrate the feasibility and effectiveness of the proposed model. [ABSTRACT FROM AUTHOR]

Significant efforts have been devoted to the development of catalysts for the removal of environmental pollutants. However, screening catalysts through trial and error consumes a lot of time and resources. Here we present a machine learning approach for selective catalytic reduction (SCR) catalyst discovery based on a custom-build database covering over 2000 related reports. Catalyst characteristics and working conditions were selected as features to predict catalyst activities. The extra tree regression model was identified as the best performer among the eight algorithms examined here for this purpose. Elements with strong oxidizing ability, such as Mn, as the active component were found to be important for developing excellent low temperature SCR catalysts using the calculated feature importance scores. The optimized machine learning model was used to aid the identification of Mn-based SCR catalysts and the NO conversion rate of the Mn–Ce–Co catalyst is greater than 80% in a wide temperature range of 150–300 °C. [ABSTRACT FROM AUTHOR]

Cu‐CHA is the state‐of‐the‐art catalyst for the Selective Catalytic Reduction (SCR) of NOx in vehicle applications. Although extensively studied, diverse mechanistic proposals still stand in terms of the nature of active Cu‐ions and reaction pathways in SCR working conditions. Herein we address the redox mechanism underlying Low‐Temperature (LT) SCR on Cu‐CHA by an integration of chemical‐trapping techniques, transient‐response methods, operando UV/Vis‐NIR spectroscopy with modelling tools based on transient kinetic analysis and density functional theory calculations. We show that the rates of the Reduction Half‐Cycle (RHC) of LT‐SCR display a quadratic dependence on CuII, thus questioning mechanisms based on isolated CuII‐ions. We propose, instead, a CuII‐pair mediated LT‐RHC pathway, in which NO oxidative activation to mobile nitrite‐precursor intermediates accounts for CuII reduction. These results highlight the role of dinuclear Cu complexes not only in the oxidation part of LT‐SCR, but also in the RHC reaction cascade. [ABSTRACT FROM AUTHOR]

Tryptophan metabolism plays a crucial role in facilitating various cellular processes essential for maintaining normal cellular function. Indoleamine 2,3-dioxygenase 1 (IDO1) catalyzes the conversion of tryptophan (Trp) into kynurenine (Kyn), thereby initiating the degradation of Trp. The resulting Kyn metabolites have been implicated in the modulation of immune responses. Currently, the role of IDO1-mediated tryptophan metabolism in the process of viral infection remains relatively unknown. In this study, we discovered that classical swine fever virus (CSFV) infection of PK-15 cells can induce the expression of IDO1, thereby promoting tryptophan metabolism. IDO1 can negatively regulate the NF-κB signaling by mediating tryptophan metabolism, thereby facilitating CSFV replication. We found that silencing the IDO1 gene enhances the expression of IFN-α, IFN-β, and IL-6 by activating the NF-κB signaling pathway. Furthermore, our observations indicate that both silencing the IDO1 gene and administering exogenous tryptophan can inhibit CSFV replication by counteracting the cellular autophagy induced by Rapamycin. This study reveals a novel mechanism of IDO1-mediated tryptophan metabolism in CSFV infection, providing new insights and a theoretical basis for the treatment and control of CSFV.IMPORTANCEIt is well known that due to the widespread use of vaccines, the prevalence of classical swine fever (CSF) is shifting towards atypical and invisible infections. CSF can disrupt host metabolism, leading to persistent immune suppression in the host and causing significant harm when co-infected with other diseases. Changes in the host's metabolic profiles, such as increased catabolic metabolism of amino acids and the production of immunoregulatory metabolites and their derivatives, can also influence virus replication. Mammals utilize various pathways to modulate immune responses through amino acid utilization, including increased catabolic metabolism of amino acids and the production of immunoregulatory metabolites and their derivatives, thereby limiting viral replication. Therefore, this study proposes that targeting the modulation of tryptophan metabolism may represent an effective approach to control the progression of CSF., Competing Interests: The authors declare no conflict of interest.

Importance: CSFV infection in pigs causes persistent high fever, hemorrhagic necrotizing multi-organ inflammation, and high mortality, which seriously threatens the global swine industry. Cell death is an essential immune response of the host against pathogen invasion, and lymphopenia is the most typical clinical feature in the acute phase of CSFV infection, which affects the initial host antiviral immunity. As an "old" virus, CSFV has evolved mechanisms to evade host immune response after a long genetic evolution. Here, we show that necroptosis is a limiting host factor for CSFV infection and that CSFV-induced autophagy can subvert this host defense mechanism to promote its sustained replication. Our findings reveal a complex link between necroptosis and autophagy in the process of cell death, provide evidence supporting the important role for CSFV in counteracting host cell necrosis, and enrich our knowledge of pathogens that may subvert and evade this host defense., Competing Interests: The authors declare no conflict of interest.

Cu-CHA is the state-of-the-art catalyst for the Selective Catalytic Reduction (SCR) of NOx in vehicle applications. Although extensively studied, diverse mechanistic proposals still stand in terms of the nature of active Cu-ions and reaction pathways in SCR working conditions. Herein we address the redox mechanism underlying Low-Temperature (LT) SCR on Cu-CHA by an integration of chemical-trapping techniques, transient-response methods, operando UV/Vis-NIR spectroscopy with modelling tools based on transient kinetic analysis and density functional theory calculations. We show that the rates of the Reduction Half-Cycle (RHC) of LT-SCR display a quadratic dependence on Cu II , thus questioning mechanisms based on isolated Cu II -ions. We propose, instead, a Cu II -pair mediated LT-RHC pathway, in which NO oxidative activation to mobile nitrite-precursor intermediates accounts for Cu II reduction. These results highlight the role of dinuclear Cu complexes not only in the oxidation part of LT-SCR, but also in the RHC reaction cascade., (© 2021 Wiley-VCH GmbH.)