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Graph Neural Networks (GNNs) have attracted increasing attentions for multimodal Emotion Recognition in Conversation (ERC) due to their good performance in contextual understanding. However, most existing GNN-based methods suffer from two challenges: 1) How to explore and propagate appropriate information in a conversational graph. Typical GNNs in ERC neglect to mine the emotion commonality and discrepancy in the local neighborhood, leading to learn similar embbedings for connected nodes. However, the embeddings of these connected nodes are supposed to be distinguishable as they belong to different speakers with different emotions. 2) Most existing works apply simple concatenation or co-occurrence prior for modality combination, failing to fully capture the emotional information of multiple modalities in relationship modeling. In this paper, we propose a multimodal Decoupled Distillation Graph Neural Network (D2GNN) to address the above challenges. Specifically, D2GNN decouples the input features into emotion-aware and emotion-agnostic ones on the emotion category-level, aiming to capture emotion commonality and implicit emotion information, respectively. Moreover, we design a new message passing mechanism to separately propagate emotion-aware and -agnostic knowledge between nodes according to speaker dependency in two GNN-based modules, exploring the correlations of utterances and alleviating the similarities of embeddings. Furthermore, a multimodal distillation unit is performed to obtain the distinguishable embeddings by aggregating unimodal decoupled features. Experimental results on two ERC benchmarks demonstrate the superiority of the proposed model. Code is available at https://github.com/gityider/D2GNN.

Learning with noisy labels has become more and more popular because of the expensive costs of collecting high-quality labels. To avoid the decrease in model performance caused by incorrect annotations, some existing methods try to select reliable samples based on the local structure of nearest neighbors in the feature space. However, the information from local neighbors is unreliable when encountering extremely noisy cases, and selecting samples only using the feature space may result in clear noise accumulation. To this end, we propose a Dual-Space Collaborative Learning (DSCL) framework to boost classification accuracy by jointly using the complementarity information from both semantic and feature spaces. Specifically, a collaborative selection module is designed by constructing a set of global prototypes and high-confidence semantic predictions, which enhances the robustness of the sample selection process. Moreover, a collaborative regularization module is constructed by the bidirectional adjustment between the semantic and feature spaces, which effectively alleviates the noise accumulation issue caused by sample selection bias in a single space. By simultaneously utilizing the two modules, our method improves the accuracy of sample selection and mitigates the degradation caused by noisy labels. Extensive experimental results indicate the superior performance of DSCL compared with various baselines. The source codes of this paper are available at https://github.com/DarrenZZhang/DSCL

A unique feature of coronaviruses is their utilization of self-encoded nonstructural protein 16 (nsp16), 2'-O-methyltransferase (2'-O-MTase), to cap their RNAs through ribose 2'-O-methylation modification. This process is crucial for maintaining viral genome stability, facilitating efficient translation, and enabling immune escape. Despite considerable advances in the ultrastructure of SARS-CoV-2 nsp16/nsp10, insights into its molecular mechanism have so far been limited. In this study, we systematically characterized the 2'-O-MTase activity of nsp16 in SARS-CoV-2, focusing on its dependence on nsp10 stimulation. We observed cross-reactivity between nsp16 and nsp10 in various coronaviruses due to a conserved interaction interface. However, a single residue substitution (K58T) in SARS-CoV-2 nsp10 restricted the functional activation of MERS-CoV nsp16. Furthermore, the cofactor nsp10 effectively enhanced the binding of nsp16 to the substrate RNA and the methyl donor S-adenosyl-L-methionine (SAM). Mechanistically, His-80, Lys-93, and Gly-94 of nsp10 interacted with Asp-102, Ser-105, and Asp-106 of nsp16, respectively, thereby effectively stabilizing the SAM binding pocket. Lys-43 of nsp10 interacted with Lys-38 and Gly-39 of nsp16 to dynamically regulate the RNA binding pocket and facilitate precise binding of RNA to the nsp16/nsp10 complex. By assessing the conformational epitopes of nsp16/nsp10 complex, we further determined the critical residues involved in 2'-O-MTase activity. Additionally, we utilize an in vitrobiochemical platform to screen potential inhibitors targeting 2'-O-MTase activity. Overall, our results significantly enhance the understanding of viral 2'-O methylation process and mechanism, providing valuable targets for antiviral drug development.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is still epidemic around the world. The manipulation of SARS-CoV-2 is restricted to biosafety level 3 laboratories (BSL-3). In this study, we developed a SARS-CoV-2 ΔN-GFP-HiBiT replicon delivery particles (RDPs) encoding a dual reporter gene, GFP-HiBiT, capable of producing both GFP signal and luciferase activities. Through optimal selection of the reporter gene, GFP-HiBiT demonstrated superior stability and convenience for antiviral evaluation. Additionally, we established a RDP infection mouse model by delivering the Ngene into K18-hACE2 KI mouse through lentivirus. This mouse model supports RDP replication and can be utilized for in vivoantiviral evaluations. In summary, the RDP system serves as a valuable tool for efficient antiviral screening and studying the gene function of SARS-CoV-2. Importantly, this system can be manipulated in BSL-2 laboratories, decreasing the threshold of experimental requirements.

•Biogas purified by treated wasterwater was recommended.•It is the reutilization of the wastewater.•The thermodynamic results of the direct-fired absorption chiller were analyzed.•Biogas refrigeration provides an innovative design in the renewable energy.•Biogas refrigeration has the advantage of utilizing energy on site.

V2O5is a promising pseudocapacitive material for electrochemical energy storage with balanced power and energy density. Understanding the charge-storage mechanism is of significance to further improve the rate performance. Here, we report an electrochemical study of individual V2O5particles using scanning electrochemical cell microscopy with colocalized electron microscopy. A carbon sputtering procedure is proposed for the pristine V2O5particles to improve their structure stability and electronic conductivity. The achieved high-quality electrochemical cyclic voltammetry results, structural integrity, and high oxidation to reduction charge ratio (as high as 97.74%) assured further quantitative analysis of the pseudocapacitive behavior of single particles and correlation with local particle structures. A broad range of capacitive contribution is revealed, with an average ratio of 76% at 1.0 V/s. This study provides new opportunities for quantitative analysis of the electrochemical charge-storage process at single particles, especially for electrode materials with electrolyte-induced instability.

To prevent the exploitation of wild agarwood, the development of artificial agarwood through fungal inoculation is a promising method, but finding species that produce efficient high-quality agarwood remains difficult. In this study, a fungal inducer was prepared using wild agarwood containing fungi and high-throughput sequencing was performed to determine its species makeup. Subsequently, it was used to inoculate Aquilaria sinensis(Lour.) Spreng. The induced agarwood (IA), wild agarwood (WA), and nonresinous whitewood (WW) were analyzed for the extract content. In addition, liquid and gas chromatography–mass spectrometry was used to determine the chemical composition of the samples. The results were used to evaluate the quality of the IA. Mortierella humilisLinnem. ex W.Gams, Oidiodendron maius(Barron), and Tolypocladium album(W. Gams) Quandt, Kepler, and Spatafora were the fungal inducers that were discovered to produce agarwood. The extracts from the IA and WA contained 64 and 69 2-(2-phenylethyl)chromones, respectively, while there were none in the WW. Furthermore, 20 (relative content 36.19%) and 27 (relative content 54.92%) sesquiterpenes were identified in the essential oils of the IA and WA, respectively, and none were identified in the WW. The fungal inducer that was prepared from the WA effectively improves the quality of the agarwood, which is extremely similar to that of the WA.

Understanding and establishing the structure-activity relation of nanoparticles is a prerequisite for rational design of high-performance electrocatalysts. Cu2O nanoparticles enclosed with different crystal facets, namely, o-Cu2O NPs with {111} facets, c-Cu2O NPs with {100} facets are prepared and their electrocatalytic properties for oxygen evolution reaction (OER) in alkaline condition are evaluated at single nanoparticle level with a combination of scanning electrochemical cell microscopy and scanning electron microscopy. It is found that the o-Cu2O NPs have significantly superior OER electrocatalytic activity compared to c-Cu2O, which is almost inert. The estimated turnover frequency (TOF) at 1.97 V vs.RHE on {111} facet increases from 4 s−1to 115 s−1with the octahedron edge length decreasing from 1.3 µm to 100 nm. Deposition of carbon on c-Cu2O surface barely promotes the activity, suggesting the inherent poor electric conductivity within the nanocrystal is most likely the reason for low activity. This work provides direct probing to single transition metal oxide crystals with dramatically different activity.

Podocyte dysfunction plays an essential role in the pathogenesis of proteinuria and glomerulosclerosis. However, the mechanism underlying podocyte dysfunction in many common forms of chronic kidney diseases remains poorly understood. Here we tested the hypothesis that podocytes may undergo epithelial-to-mesenchymal transition after injury. Conditionally immortalized mouse podocytes were incubated with transforming growth factor (TGF)-β1, a potent fibrogenic cytokine that is up-regulated in the diseased kidney. TGF-β1 suppressed the slit diaphragm-associated protein P-cadherin, zonula occludens-1, and nephrin, a change consistent with loss of the epithelial feature. Meanwhile, TGF-β1 induced the expression of the intermediate filament protein desmin and interstitial matrix components fibronectin and collagen I. Furthermore, TGF-β1 promoted the expression and secretion of matrix metalloproteinase-9 by podocytes. Functionally, TGF-β1 increased albumin permeability across podocyte monolayers, as demonstrated by a paracellular albumin influx assay. The expression of Snail, a key transcriptional factor that has been implicated in initiating epithelial-to-mesenchymal transition, was induced by TGF-β1, and ectopic expression of Snail suppressed P-cadherin and nephrin in podocytes. In vivo, in addition to loss of nephrin and zonula occludens-1, mesenchymal markers such as desmin, fibroblast-specific protein-1, and matrix metalloproteinase-9 could be observed in glomerular podocytes of diabetic nephropathy. These results suggest that podocyte dedifferentiation and mesenchymal transition could be a potential pathway leading to their dysfunction, thereby playing a role in the genesis of proteinuria.

Retinoic acid (RA), an active metabolite of vitamin A, plays a critical role in the regulation of cell proliferation, survival, and differentiation. RA action is primarily mediated through its receptors, ligand-dependent transcription factors of the steroid/thyroid/vitamin D nuclear receptor superfamily. Recent studies indicate that administration of RA mitigates progressive kidney disease, underscoring its renoprotective potential. In this study, we investigated the effects of 9-cis-RA on glomerular mesangial cell activation induced by transforming growth factor (TGF)-β1 using an in vitrocell culture system. In human mesangial cells 9-cis-RA suppressed TGF-β1-induced α-smooth muscle actin, fibronectin, and plasminogen activator inhibitor-1 expression, but it did not significantly affect cell proliferation and survival. Interestingly, 9-cis-RA induced hepatocyte growth factor (HGF) mRNA expression and protein secretion, stimulated HGF promoter activity, and activated c-met receptor phosphorylation. Similar to HGF, 9-cis-RA induced expression of the Smad transcriptional co-repressor TGIF in mesangial cells. Overexpression of exogenous TGIF by transfection or 9-cis-RA treatment suppressed trans-activation of the TGF-β-responsive promoter. Moreover, conditional ablation of the c-met receptor completely abolished the anti-fibrotic effect of 9-cis-RA and abrogated TGIF induction. Collectively, these results indicate that 9-cis-RA possesses anti-fibrotic ability by antagonizing TGF-β1 in mesangial cells and that 9-cis-RA activity is likely mediated through a mechanism dependent on HGF/c-met receptor signaling.

Hepatocyte growth factor (HGF) receptor is a transmembrane receptor tyrosine kinase encoded by the c-metprotooncogene. In this study, we demonstrated that c-met expression was upregulated in the kidney after obstructive injury in mice. Because the pattern of c-met induction was closely correlated with transforming growth factor-β1 (TGF-β1) expression in vivo, we further investigated the regulation of c-met expression in renal tubular epithelial (HKC) cells by TGF-β1 in vitro. Real-time RT-PCR and Northern and Western blot analyses revealed that TGF-β1 significantly induced c-met expression in HKC cells, which primarily took place at the gene transcriptional level. Overexpression of inhibitory Smad7 completely abolished c-met induction, indicating its dependence on Smad signaling. Interestingly, TGF-β1-induced c-met expression was also contingent on a functional Sp1, as ablation of Sp1 binding with mithramycin A abrogated c-met induction in HKC cells. Transfection and sequence analysis identified a cis-acting TGF-β1-responsive region in the c-met promoter, in which resided a putative Smad-binding element (SBE) and an adjacent Sp1 site. TGF-β1 not only induced Smad binding to the SBE/Sp1 sites in the c-met promoter, but also enhanced the binding of Sp proteins. Furthermore, Sp1 could form a complex with Smads in a TGF-β1-dependent fashion. These results suggest a novel regulatory mechanism controlling c-met expression by TGF-β1 in renal epithelial cells, in which both Smad and Sp proteins participate and cooperate in activating c-metgene transcription.

We investigated the expression pattern and underlying mechanism that controls hepatocyte growth factor (HGF) receptor (c-met) expression in normal kidney and a variety of kidney cells. Immunohistochemical staining showed widespread expression of c-met in mouse kidney, a pattern closely correlated with renal expression of Sp1 and Sp3 transcription factors. In vitro, all types of kidney cells tested expressed different levels of c-met, which was tightly proportional to the cellular abundances of Sp1 and Sp3. Both Sp1 and Sp3 bound to the multiple GC boxes in the promoter region of the c-metgene. Coimmunoprecipitation suggested a physical interaction between Sp1 and Sp3. Functionally, Sp1 markedly stimulated c-met promoter activity. Although Sp3 only weakly activated the c-met promoter, its combination with Sp1 synergistically stimulated c-mettranscription. Conversely, deprivation of Sp proteins by transfection of decoy Sp1 oligonucleotide or blockade of Sp1 binding with mithramycin A inhibited c-met expression. The c-met receptor in all types of kidney cells was functional and induced protein kinase B/Akt phosphorylation in a distinctly dynamic pattern after HGF stimulation. These results indicate that members of the Sp family of transcription factors play an important role in regulating constitutive expression of thec-metgene in all types of renal cells. Our findings suggest that HGF may have a broader spectrum of target cells and possess wider implications in kidney structure and function than originally thought.

Experiments have been carried out to assess the potential of differential pulse voltammetry and potential stripping analysis for determining Pb, Cu and Cd directly in dissolved honey samples using a flow-through cell. With the hanging mercury drop electrode Pb alone can be determined only if the electrode is first modified in-situ with Triton X 100 to increase the separation between the Pb peak and a broad, interfering adsorption peak which overlaps the Cu peak. If the (more sensitive) thin film mercury electrode is used the interference encountered is less so also Cu and Cd can be determined. With potentiometric stripping analysis Cu and Pb can be determined using normal procedures. The determination of Cd, however, can only be carried out if the concentration of the oxidizing agent [Hg(II)] in solution is decreased. A good agreement has been obtained between the values found and those obtained after high pressure digestion of the samples.

This paper focuses on a novel model of pantograph multi-group models with dispersal and stochastic perturbation. The effects of proportional delay, multiple dispersal among groups, and stochastic perturbation are all taken into account in this model. By means of combining graph theory with Lyapunov method, sufficient criteria are obtained to ensure the globally exponential stability of the model, which are in the forms of Lyapunov functions and the coefficients, respectively. Moreover, to show the applicability of our results, coefficient-type criterion is employed to stochastic coupled pantograph oscillators described by two digraphs successfully. Finally, a numerical example is offered to demonstrate the validity of the theoretic results. [ABSTRACT FROM AUTHOR]