With the advent of the post-pandemic era characterised by increasing social uncertainty, the public is placing higher demands on the trust in news media. According to the 2023 Edelman Trust Barometer, the image of the...
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With the advent of the post-pandemic era characterised by increasing social uncertainty, the public is placing higher demands on the trust in news media. According to the 2023 Edelman Trust Barometer, the image of the media in the public's mind is deteriorating. Why don't they trust the media? What are the reasons given by the public when the media is denounced as unscrupulous? Taking the Liu Xuezhou incident as a typical case, the study extracts key elements from 5,225 related microblog texts, identifies the main topics of public discussion with the help of LDA topic modelling, clarifies the referential dimension of unscrupulous media with the help of pointwise mutual information, and analyzes netizens' evaluations related to different referential levels of the media through visual semantic networks, which can help formulate dialectical thinking on media trust in the context of China in the era of social media.
Herein, we explored the charge transfer (CT) effect on the excited-state structural and electronic evolution of N,N '-diphenyl-dihydrodibenzo[a,c]phenazine (DPAC) featuring various electron-donating groups (EDGs)....
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Herein, we explored the charge transfer (CT) effect on the excited-state structural and electronic evolution of N,N '-diphenyl-dihydrodibenzo[a,c]phenazine (DPAC) featuring various electron-donating groups (EDGs). Upon photoexcitation, DPAC molecules undergo a sequential multistep structural transformation along the Franck-Condon (FC) state, CT-controlled bent state (responsible for E1 & horbar;420 nm), and twisted state (responsible for E2 & horbar;600 nm). By introducing different EDGs to the DPAC core, we can fine-tune the balance between the inherent decay of the CT-controlled bent state and its progression into the twisted state by adjusting the CT effect. As the electron-donating ability of the EDG increases, the strong CT effect can produce a "deep" (stable) CT-controlled bent state, in which the transformation of the excited molecular skeleton from bent into twisted was partly suppressed. This research provides valuable insights into organic chromophores' excited-state structural and electronic evolution, revealing how competitive decay pathways are contingent upon the CT effect.
Organic donor-acceptor cocrystals of pi-conjugated molecues have shown diverse applications in materials science. However, most cocrystals exist in neutral forms dominated by pi-pi interactions, while the ionic congen...
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Organic donor-acceptor cocrystals of pi-conjugated molecues have shown diverse applications in materials science. However, most cocrystals exist in neutral forms dominated by pi-pi interactions, while the ionic congeners and corresponding properties are rarely studied due to difficulties in harnessing the degree of charge transfer. Herein, we report cocrystals of axially N-embedded quasi-carbon nanohoops (DPP-D and DPP-T) with electron deficient guests. By modulating the electron affinity of the acceptor guests, the electronic structures of the complexes can be tuned from neutral to ionic states. Specifically, DPP-D interacts with TCNB molecules to form neutral superstructures via intermolecular pi-pi interactions, giving rise to a deep-red emission in the solid state. In contrast, an ionic complex showing near-infrared region absorptions and paramagnetic character on account of strong charge-transfer interactions is generated when DDQ molecules are involved. Their unique properties can be explained by different degrees of charge transfer and assembly modes, which have clearly been manifested by crystal structures and theoretical calculations. Our studies provide rare examples of pi-conjugated macrocycle-based donor-acceptor cocrystals in both neutral and ionic forms, and give insight to the design of multicomponent carbon nanomaterials.
Hepatitis-hydropericardium syndrome, caused by fowl adenovirus serotype 4 (FAdV-4), has resulted in significant economic damage to the poultry industry. To monitor viral exposure and vaccine efficacy, some traditional...
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Hepatitis-hydropericardium syndrome, caused by fowl adenovirus serotype 4 (FAdV-4), has resulted in significant economic damage to the poultry industry. To monitor viral exposure and vaccine efficacy, some traditional antibody-based immunoassays have been developed for detecting anti-FAdV-4 antibodies. However, these assays have some drawbacks including multi-step operations and higher production cost. Recently, nanobodies are regarded as a promising tool for developing immunoassays. In the study, 23 nanobodies against FAdV-4 were screened and expressed with horseradish peroxidase (HRP) in the HEK293T cells. Then, the FAdV-4-Nb28-HRP fusion protein was selected for developing competitive enzyme-linked immunoassays (cELISA) to detect antiFAdV-4 antibodies in the chicken sera. The optimal concentrations and dilutions for the coating antigen, fusion protein and testing sera were determined to be 400 ng/well, 1:80 and 1:20, respectively. After the coated plates were vacuumized and stored, the operation of cELISA to detect clinical chicken sera was only one-step and the full time was 75 min. The cELISA also exhibited high sensitivity, specificity, reproducibility and good agreement with the commercial ELISA kit. When the sequential sera from the challenged chickens were tested, the cELISA showed superior sensitivity compared with the commercial ELISA kit. Moreover, epitope mapping revealed that the nanobody specifically recognized the sites GLN235 ASN236 SER238 of the fiber-1 protein, highly conserved among different FAdV-4 isolates and different from the FAdV-1 and-8. The results indicated that cELISA can specifically detect anti-FAdV-4 antibodies. Collectively, the developed one-step nanobody-based cELISA is an ideal method for epidemiological investigation and vaccine immune evaluation of FAdV-4.
pi-Conjugated molecules exhibit prosperous excited-state processes and tunable luminescence proper-ties, as the key building blocks for fabricating smart luminescent materials. In this review, we focus on the vibratio...
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pi-Conjugated molecules exhibit prosperous excited-state processes and tunable luminescence proper-ties, as the key building blocks for fabricating smart luminescent materials. In this review, we focus on the vibration-induced emission (VIE) of saddle-shaped dihydrophenazine (DHP) derivatives, which involves dynamic conformation changes of photoexcited molecules to planar configuration in charge of the large Stokes-shifted emission. By modifying the rigid-flexible fused skeleton of DHP, a continuously tunable emission over a wide range can be achieved through the dynamic bent-to-planar transformations of a single-molecule entity. The interplay of aromaticity and steric hindrance was proposed as the regu-lation mechanism, and applied to clarify how the luminescence characteristics were affected by the intramolecular steric hindrance and ring tension. By taking advantage of the VIE phenomenon, i.e., dra-matic structural/electronic responses and sensitive vibration-degree-dependent emissions, donor -bridge-acceptor systems with conformation-dependent electron/energy donors were fabricated, and the output of colorful fluorescent signals visible to the naked eye were realized in response to minor inter-/intra-molecular stimulations. Furthermore, the VIE phenomenon of DHPs brings new possibilities for obtaining different conductance features as one molecule changes its conformation in the metal- molecule-metal junction arrangement. This review includes the recent progress in VIE research as well as our perspectives on future directions.(c) 2022 Elsevier B.V. All rights reserved.
Hepatitis E virus (HEV) is an emerging zoonotic pathogen that is transmitted primarily through the fecal-oral route and can cause acute hepatitis in humans. Since HEV was identified as a zoonotic pathogen, different s...
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Hepatitis E virus (HEV) is an emerging zoonotic pathogen that is transmitted primarily through the fecal-oral route and can cause acute hepatitis in humans. Since HEV was identified as a zoonotic pathogen, different species of HEV strains have been globally identified from various hosts, leading to an expanding range of hosts. The HEV genome consists of a 5' noncoding region, three open reading frames (ORFs), and a 3' noncoding region. The ORF3 protein is the smallest but has many functions in HEV release and pathogenesis. In this review, we systematically summarize recent progress in understanding the functions of the HEV ORF3 protein in virion release, biogenesis of quasi-enveloped viruses, antigenicity, and host environmental regulation. This review will help us to understand HEV replication and pathogenesis mechanisms better.
The SEIARN model is often used to predict infectious diseases, but the parameter estimation of the SEIARN model has always been one of the difficulties in this research. Traditional statistical and empirical estimatio...
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The SEIARN model is often used to predict infectious diseases, but the parameter estimation of the SEIARN model has always been one of the difficulties in this research. Traditional statistical and empirical estimation methods have certain limitations. To this end, we designed an SSA‐based SEIARN parameter adaptive model, optimized parameters through SSA, and used historical epidemic data in Hebei, Tianjin, and Beijing for simulation. Experiments finally proved the feasibility of the algorithm.
Organic donor-acceptor cocrystals of π-conjugated molecues have shown diverse applications in materials science. However,most cocrystals exist in neutral forms dominated by π-π interactions, while the ionic congene...
Organic donor-acceptor cocrystals of π-conjugated molecues have shown diverse applications in materials science. However,most cocrystals exist in neutral forms dominated by π-π interactions, while the ionic congeners and corresponding properties are rarely studied due to difficulties in harnessing the degree of charge transfer. Herein, we report cocrystals of axially N-embedded quasi-carbon nanohoops(DPP-D and DPP-T) with electron deficient guests. By modulating the electron affinity of the acceptor guests, the electronic structures of the complexes can be tuned from neutral to ionic states. Specifically, DPP-D interacts with TCNB molecules to form neutral superstructures via intermolecular π-π interactions, giving rise to a deep-red emission in the solid state. In contrast, an ionic complex showing near-infrared region absorptions and paramagnetic character on account of strong charge-transfer interactions is generated when DDQ molecules are involved. Their unique properties can be explained by different degrees of charge transfer and assembly modes, which have clearly been manifested by crystal structures and theoretical calculations. Our studies provide rare examples of π-conjugated macrocycle-based donor-acceptor cocrystals in both neutral and ionic forms, and give insight to the design of multicomponent carbon nanomaterials.
In order to improve the high degree of close to training reality for college teaching and training, an antagonistic virtual simulation training system is constructed by analyzing and designing. First, the basic proces...
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In order to further enrich the practical guarantee conditions of training theory teaching simulation in the university and improve the level of digital, scientific and information management of professional classrooms...
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