Discovery and characterization of novel jeilongviruses in wild rodents from Hubei, China.

The genus Jeilongvirus comprises non-segmented negative-stranded RNA viruses that are classified within the Paramyxoviridae family by phylogeny. Jeilongviruses are found in various reservoirs, including rodents and bats. Rodents are typical viral reservoirs with diverse spectra and zoonotic potential. Little is currently known about jeilongviruses in rodents from central China. The study utilized high-throughput and Sanger sequencing to obtain jeilongvirus genomes, including those of two novel strains (HBJZ120/CHN/2021 (17,468 nt) and HBJZ157/CHN/2021 (19,143 nt)) and three known viruses (HBXN18/CHN/2021 (19,212 nt), HBJZ10/CHN/2021 (19,700 nt), HBJM106/CHN/2021 (18,871 nt)), which were characterized by genome structure, identity matrix, and phylogenetic analysis. Jeilongviruses were classified into three subclades based on their topology, phylogeny, and hosts. Based on the amino acid sequence identities and phylogenetic analysis of the L protein, HBJZ120/CHN/2021 and HBJZ157/CHN/2021 were found to be strains rather than novel species. Additionally, according to specific polymerase chain reaction screening, the positive percentage of Beilong virus in Hubei was 6.38%, suggesting that Beilong virus, belonging to the Jeilongvirus genus, is likely to be widespread in wild rodents. The identification of novel strains further elucidated the genomic diversity of jeilongviruses. Additionally, the prevalence of jeilongviruses in Hubei, China, was profiled, establishing a foundation for the surveillance and early warning of emerging paramyxoviruses.

Insights into the mechanism of persulfate activation with carbonated waste metal adsorbed resin for the degradation of 2,4-dichlorophenol.

Superabsorbent resin (SAR) saturated with heavy metals poses a threat to surrounding ecosystem. To promote the reutilization of waste, resins adsorbed by Fe2+ and Cu2+ were carbonized and used as catalysts (Fe@C/Cu@C) to activate persulfate (PS) for 2,4-dichlorophenol (2,4-DCP) degradation. The heterogeneous catalytic reaction was mainly responsible for 2,4-DCP removal. The synergistic effect of Fe@C and Cu@C was propitious to 2,4-DCP degradation. Fe@C/Cu@C with a ratio of 2:1 showed the highest performance of 2,4-DCP removal. 40 mg/L 2,4-DCP was completely removed within 90 min under reaction conditions of 5 mM PS, pH = 7.0 and T = 25 °C. The cooperation of Fe@C and Cu@C facilitated the redox cycling of Fe and Cu species to supply accessible PS activation sites, enhancing ROS generation for 2,4-DCP degradation. Carbon skeleton enhanced 2,4-DCP removal via radical/nonradical oxidation pathways and via its adsorption to 2,4-DCP. SO4˙-, HO˙ and O2•- were the dominate radical species involved in 2,4-DCP destruction. Meanwhile, the possible pathways of 2,4-DCP degradation were proposed based on GC-MS. Finally, recycling tests proved catalysts exhibited recyclable stability. Aiming to resource utilization, Fe@C/Cu@C with satisfactory catalysis and stability, is promising catalyst for contaminated water treatment.

The influence of turbulence on sediment phosphorus sorption.

The effect of mean flow velocity on phosphorus (P) partitioning between water and sediment has received much attention in recent decades. However, the impact of turbulence on the efficiency and capability of sediment adsorbing and desorbing dissolved inorganic phosphorus (DIP) is still unclear. A series of contrasting experiments on the sediment sorption and desorption of DIP with the flow turbulence kinetic energy (TKE) ranging from 1.95 to 2.93 pa have been conducted. It was found that the adsorbed P onto unit mass of sediment increases with the increase in TKE. It is because an increase in TKE results in a rise in the effective adsorption capacity of sediment (bm) by 20-30% during the adsorption process. The bm shows the maximum rise from 0.18 to 0.25 mg/g when TKE increases from 1.95 to 2.93 pa with a fixed sediment concentration of 0.5 g/L. To account for the direct effect of TKE on P adsorption, the Langmuir model is modified by introducing a newly defined coefficient (fA-TKE). The fA-TKE shows a good linear relationship with TKE. Comparison between the modified model and the classic model shows that the amount of adsorbed P could be overestimated by over 50% if the direct effect of turbulence intensity is ignored. The experimental data show that the increase in TKE also enhances the desorption process, with the degree of P desorption (Ddes) increased by 44%. The relation between Ddes and TKE can be well represented using a logarithmic function to quantify the direct effect of turbulence intensity on desorption of P.

Co-treatment of municipal solid waste incineration fly ash (MSWI FA) and municipal sludge: A innovative method to improve sludge dewatering with fly ash dechlorination.

The complexity of municipal sludge dewatering is a bottleneck problem limiting resource utilization. In this paper, adding municipal solid waste incineration fly ash (MSWI FA) to municipal sludge for enhanced dewatering was applied, while the chlorine salt in MSWI FA was simultaneously removed using water in municipal sludge. The effects of different dosages and chemical components of MSWI FA on municipal sludge dewatering, and the removal effect of municipal sludge washing on Cl element were investigated. The results showed that the municipal sludge's specific resistance to filtration after co-treatment was significantly reduced, and more hydrophobic channels were formed in the vacuum suction filtration of the treated municipal sludge, conducive to efficient water removal. The moisture content of municipal sludge was reduced from 96.0% to 48.3%, and the moisture reduction rate increased from 17.7% to 32.1%. The chemical composition of MSWI FA could effectively promote the dewatering of municipal sludge, among which CaO was the best, followed by CaCl2 and NaCl, and KCl was the worst. Simultaneously, the municipal sludge showed a good effect on removing Cl from MSWI FA. The minimum Cl content in the mixture after Co-treatment is 1.5%. These results could provide a new way to dispose of MSWI FA and municipal sludge.

Natural mineral-derived Fe/Mn-BC as efficient peroxydisulfate activator for 2,4-dichlorophenol removal from wastewater: Performance and sustainable catalytic mechanism.

Iron and manganese oxides/biochar composite materials (Fe/Mn-BC) are promising catalysts in the field of advanced oxidation. High purity chemical reagents are popular precursors for preparing Fe/Mn-BC, while the potential of low-cost natural minerals as precursors has been neglected. In this study, high-efficiency Fe/Mn-BC was synthesized by one-step pyrolysis method using hematite, phosphoromanganese, and bagasse. The synthesized Fe/Mn-BC removed 83.7% 2, 4-dichlorophenol (2, 4-DCP) within 30 min, about 8.8 and 10.6 times better than biochar (BC) and Fe/Mn complex, respectively. The removal of 2, 4-DCP in the Fe/Mn-BC + peroxydisulfate (PDS) system was influenced by catalyst dosage, PDS concentration, initial pH, organic acids, and chromium. Sulfate radical (SO4•-) and hydroxyl radicals (•OH) generated by Fe/Mn-BC-activated PDS have similar contribution to the degradation of 2,4-DCP. A possible removal mechanism of 2, 4-DCP in the Fe/Mn-BC + PDS system was proposed based on Electron Spin Resonance spectroscopy, free radical quenching experiments, X-ray photoelectron spectroscopy, X-ray diffraction, and electrochemical measurement. Fe0 and Fe(II) in Fe/Mn-BC play significant role in catalytic degradation of 2, 4-DCP at the early stage of the reaction (within 0-5 min). Then, the interaction between Mn and BC or structural Mn and structural Fe gradually became dominant in the later stage. Similarly, the electron transfer promoted by biochar also played an important role in this catalysis. This discovery provided a new strategy for developing iron and manganese oxides/biochar composite materials to activate PDS for the elimination of refractory organic pollutants.

A functional promoter from the archaeon Halobacterium salinarum is also transcriptionally active in E. coli.

BACKGROUND: Archaea form a third domain of life that is distinct from Bacteria and Eukarya. So far, many scholars have elucidated considerable details about the typical promoter architectures of the three domains of life. However, a functional promoter from the archaeon Halobacterium salinarum has never been studied in Escherichia coli. RESULTS: This paper found that the promoter of Halobacterium salinarum showed a promoter function in Escherichia coli. This Escherichia coli promoter structure contains - 10 box, -10 box extension and - 29 elements, however, no -35 box. The - 29 element is exercised by the TATA box in archaea. And we isolated the RM10 fragment that possessed the fusion characteristics of bacteria and archaea, which was overlapped with functionality of TATA box and - 29 elements. CONCLUSIONS: The - 29 element reflects the evolutionary relationship between the archaeal promoter and the bacterial promoter. The result possibly indicated that there may be a certain internal connection between archaea and bacteria. We hypothesized that it provided a new viewpoint of the evolutionary relationship of archaea and other organisms.

Above-room Curie temperature and barrier-layer-dependent tunneling magnetoresistance in 1T-CrO2 monolayer based magnetic tunnel junctions.

van der Waals (vdW) heterostructures based on two-dimensional (2D) ferromagnetic materials hold great potential applications in spintronics. Using the density functional theory (DFT) method and first-principles quantum transport simulation, we studied the structures, magnetic properties and spin-resolved transport of 1T-CrO2 monolayer (ML) based vdW magnetic tunnel junctions (MTJs). Owing to a high Curie temperature (TC) of 392 K and a moderate magnetic anisotropy energy (MAE) of 94 µeV of the ferromagnetic 1T-CrO2 monolayer, Cu(111)|CrO2|nML-Gr|CrO2|Cu(111) MTJs were built. Our results reveal that their tunneling magnetoresistance (TMR) ratios are dependent on the number of Gr barrier layers within a working bias voltage of 1 V. For the thin barrier layers (n = 1-2), the maintained TMR ratios can reach a giant value of about 1 × 104%, while there appears a decreasing trend with the increasing bias voltage for thick Gr layers (n = 3-5). The barrier-layer-dependent phenomenon is attributed to the decreasing transmission magnitude with increasing bias voltage in a parallel configuration (PC), which is as small as that in an anti-parallel configuration (APC) eventually. Our results would provide some guidance for future experimental fabrications of these 2D materials based MTJs.

One-step synthesis of natural montmorillonite/hematite composites with enhanced persulfate catalytic activity for sulfamethoxazole degradation: Efficiency, kinetics, and mechanism.

Along with rapid development of sulfate radicals-based advanced oxidation process, efficient, alternatively eco-friendly and cost-effective catalyst is of uppermost priority. However, expensive chemicals are used as source of metal in most of these catalysts, and lose sight of the abundant natural mineral resources on immediate surroundings. In this work, montmorillonite and hematite, two of abundantly natural minerals were utilized to prepare a persulfate catalyst (TMH@M) for sulfamethoxazole (SMX) degradation. The results indicated more than 91% of SMX was removed within 60 min in TMH@M/PS system. The degradation efficiency of SMX of TMH@M/PS combined system was impacted by SMX concentration, PS dosage and natural organic matters, and can remain stable in a certain concentration of HA/chelating agent and a wide pH range (3.01-9.06). Radical scavenging and EPR tests demonstrated 1O2, OH, and SO4- were major reactive oxygen species in the TMH@M/PS system, while the latter seems more important for degradation of SMX. The results of SEM-EDS, XRD and XPS conformed that low valence iron species (Fe0, Fe2+ and Fe3O4) on TMH@M surface are the main driving force behind PS activation to generate reactive species. Furthermore, the iron species on TMH@M surface were transformed during reaction, that in favor of mitigating metal leaching. This work presented a method based on ubiquitous natural minerals to prepare catalyst with excellent PS activate performance for organic wastewater treatment implying a new strategy in minerals utilization deeply and a promisingly alternative process for organic wastewater treatment based on mineral materials.

Visualization of Bubble Nucleation and Growth Confined in 2D Flakes.

The nucleation and growth of bubbles within a solid matrix is a ubiquitous phenomenon that affects many natural and synthetic processes. However, such a bubbling process is almost "invisible" to common characterization methods because it has an intrinsically multiphased nature and occurs on very short time/length scales. Using in situ transmission electron microscopy to explore the decomposition of a solid precursor that emits gaseous byproducts, the direct observation of a complete nanoscale bubbling process confined in ultrathin 2D flakes is presented here. This result suggests a three-step pathway for bubble formation in the confined environment: void formation via spinodal decomposition, bubble nucleation from the spherization of voids, and bubble growth by coalescence. Furthermore, the systematic kinetics analysis based on COMSOL simulations shows that bubble growth is actually achieved by developing metastable or unstable necks between neighboring bubbles before coalescing into one. This thorough understanding of the bubbling mechanism in a confined geometry has implications for refining modern nucleation theories and controlling bubble-related processes in the fabrication of advanced materials (i.e., topological porous materials).

Self-Compacting Alkali-Activated Materials: Progress and Perspectives.

Alkali-activated materials (AAMs) are considered to be alternative cementitious materials for civil infrastructures. Nowadays, efforts have been made in developing AAMs with self-compacting ability. The obtained self-compacting AAMs (SCAAMs) accomplish superior passing and filling properties as well as excellent mechanical and environmental advantages. This work critically revisits recent progresses in SCAAMs including mixture proportions, fresh properties, mechanical strength, microstructure, acid and sulfate resistance, high temperature behaviors, impact resistance and interface shear strength. To facilitate direct comparison and interpretation of data from different publications, mixture proportions were normalized in terms of the content of key reactive components from precursors and activators, and correlation with mechanical behaviors was made. Moreover, special attention was paid to current research challenges and perspectives to promote further investigation and field application of SCAAMs as advanced construction material.

6-Formylindolo[3,2-b]carbazole reduces apoptosis induced by benzo[a]pyrene in a mitochondrial-dependent manner.

Benzo[a]pyrene (B[a]P), a potent carcinogen, has been proved that it can induce apoptosis via activation of the aryl hydrocarbon receptor (AhR) pathway. The metabolite of tryptophan 6-formylindolo[3,2-b]carbazole (FICZ), an endogenous activator of AhR, plays bifunctional roles in cell growth and apoptosis. However, whether and how FICZ can reduce the toxicity of B[a]P and the mechanism underlying this remain unclear. In this study, FICZ interfered with the toxicity of B[a]P in mouse hepatocarcinoma cell line Hepa1-6. The results of the MTT assay indicated that FICZ and B[a]P made opposite effects on cell proliferation. The scratch-wound healing assay showed that B[a]P (1 µM for 24 hr) exposure triggered cell migration and that was inhibited by FICZ (10 nM). In addition, FICZ ameliorated B[a]P-induced apoptosis by inhibiting reactive oxygen species generation and caspase-3 activation, as well as increasing reduced glutathione level in mitochondria. Furthermore, gene expression analyses indicated that FICZ competed with B[a]P, which reduced the transcriptional activation of the cyp1a1 and cyp1b1 genes, as well as Bcl2 and P53. Accordingly, the interaction between FICZ and B[a]P in the AhR pathway inhibited apoptosis in a mitochondrial-dependent manner, suggesting that endogenous compound may reduce the toxicity of exogenous pollutant in vivo and providing an available way to improve health condition related to the hepatic metabolic disorder.

Quality control of imbalanced mass spectra from isotopic labeling experiments.

BACKGROUND: Mass spectra are usually acquired from the Liquid Chromatography-Mass Spectrometry (LC-MS) analysis for isotope labeled proteomics experiments. In such experiments, the mass profiles of labeled (heavy) and unlabeled (light) peptide pairs are represented by isotope clusters (2D or 3D) that provide valuable information about the studied biological samples in different conditions. The core task of quality control in quantitative LC-MS experiment is to filter out low-quality peptides with questionable profiles. The commonly used methods for this problem are the classification approaches. However, the data imbalance problems in previous control methods are often ignored or mishandled. In this study, we introduced a quality control framework based on the extreme gradient boosting machine (XGBoost), and carefully addressed the imbalanced data problem in this framework. RESULTS: In the XGBoost based framework, we suggest the application of the Synthetic minority over-sampling technique (SMOTE) to re-balance data and use the balanced data to train the boosted trees as the classifier. Then the classifier is applied to other data for the peptide quality assessment. Experimental results show that our proposed framework increases the reliability of peptide heavy-light ratio estimation significantly. CONCLUSIONS: Our results indicate that this framework is a powerful method for the peptide quality assessment. For the feature extraction part, the extracted ion chromatogram (XIC) based features contribute to the peptide quality assessment. To solve the imbalanced data problem, SMOTE brings a much better classification performance. Finally, the XGBoost is capable for the peptide quality control. Overall, our proposed framework provides reliable results for the further proteomics studies.

Hexavalent chromium remediation based on the synergistic effect between chemoautotrophic bacteria and sulfide minerals.

Hexavalent chromium (Cr(VI)) is an environmental concern due to the carcinogenic and mutagenic effect on living organisms. Sulfide minerals based Cr(VI) reduction is an economical and efficient strategy for Cr(VI) remediation. In this study, Cr(VI) reduction through the synergistic effect between chemoautotrophic bacteria and sulfide mineral is systematically investigated. Sulfide minerals dissolution and Cr(VI) reduction performance highly depends on mineral acid soluble property. Cr(VI) reduction capacity of pyrrhotite, pyrite, marcasite and sphalerite was 50, 104, 104 and 44 mg/g (Cr(VI)/mineral) respectively in the biotic system. Acidithiobacillus ferrooxidans (A. ferrooxidans) significantly enhanced pyrite and marcasite based Cr(VI) reduction kinetic and capacity. Proton consumption, iron coprecipitation and the biological activity deficiency in the abiotic system significantly inhibited Cr(VI) reduction. Elemental sulfur and secondary iron mineral as the main composition of the passivation layer inhibited sustainable Cr(VI) reduction. A. ferrooxidans facilitated acid nonsoluble mineral dissolution and surface passivation layer removal, and promoted Cr(VI) reduction. Acid nonsoluble sulfide mineral disulfide bond rapture, S°/Sn2- oxidization, and Fe(III)/Cr(III) dissolution were accelerated by A. ferrooxidans, which facilitated Cr(VI) reduction reactive sites regeneration. Our study demonstrated that chemoautotrophic bacterial accelerated Cr(VI) reduction reaction through promoting acid nonsoluble sulfide mineral dissolution. This research is of environmental and practical significance to remediate redox sensitive contaminant based on the synergistic effect between sulfide minerals and chemoautotrophic A. ferrooxidans.

Synergistic effect between sulfide mineral and acidophilic bacteria significantly promoted Cr(VI) reduction.

Natural pyrite was an economical choice for efficient Cr(VI) remediation, while its deep utilization was inhibited due to the passivation effect. In this study, pyrite passivation/dissolution and active sites regeneration mechanism under the activity of acidophilic bacteria with different energy metabolism characteristic in Cr(VI) reduction have been investigated. The reduction capacity was in the order of Acidithiobacillus thiooxidans, Acidithiobacillus ferrooxidans(S), Acidithiobacillus ferrooxidans(Fe), Leptospirillum ferrooxidans and chemical control. The maximal reduction efficiency was achieved in A. thiooxidans system, which is 4.5 times higher than the L. ferrooxidans system. In chemical system, sulfur and Fe(III)/Cr(III)-oxyhydroxysulphate accumulation would result in pyrite passivation. A. thiooxidans attached on pyrite surface and exerted synergistic effect on pyrite corrosion coupled with Cr(VI). Sulfur oxidation promoted proton regeneration, pyrite lattice Fe(II) dissolution and active sites regeneration, which were beneficial to sustainable Cr(VI) reduction. Secondary iron mineral formation on pyrite was accelerated with the iron oxidation bacteria activity increasing. Excessive oxidation to surface sites Fe(II) and the accumulation of S0/Sn2- led to the passivation effect in L. ferrooxidans system. Cr(VI) acquired electron from Fe(II) and disulfide and resulted in the bond break between them. The combined effect of specific sulfur oxidizing bacteria activity and Cr(VI) oxidation efficient promoted pyrite dissolution and active sites regeneration. The interaction between acidophilic bacteria and pyrite significantly enhanced Cr(VI) reduction efficiency.

Microbial functional genes enriched in the Xiangjiang River sediments with heavy metal contamination.

BACKGROUND: Xiangjiang River (Hunan, China) has been contaminated with heavy metal for several decades by surrounding factories. However, little is known about the influence of a gradient of heavy metal contamination on the diversity, structure of microbial functional gene in sediment. To deeply understand the impact of heavy metal contamination on microbial community, a comprehensive functional gene array (GeoChip 5.0) has been used to study the functional genes structure, composition, diversity and metabolic potential of microbial community from three heavy metal polluted sites of Xiangjiang River. RESULTS: A total of 25595 functional genes involved in different biogeochemical processes have been detected in three sites, and different diversities and structures of microbial functional genes were observed. The analysis of gene overlapping, unique genes, and various diversity indices indicated a significant correlation between the level of heavy metal contamination and the functional diversity. Plentiful resistant genes related to various metal were detected, such as copper, arsenic, chromium and mercury. The results indicated a significantly higher abundance of genes involved in metal resistance including sulfate reduction genes (dsr) in studied site with most serious heavy metal contamination, such as cueo, mer, metc, merb, tehb and terc gene. With regard to the relationship between the environmental variables and microbial functional structure, S, Cu, Cd, Hg and Cr were the dominating factor shaping the microbial distribution pattern in three sites. CONCLUSIONS: This study suggests that high level of heavy metal contamination resulted in higher functional diversity and the abundance of metal resistant genes. These variation therefore significantly contribute to the resistance, resilience and stability of the microbial community subjected to the gradient of heavy metals contaminant in Xiangjiang River.

Analysis of the intestinal microbial community structure of healthy and long-living elderly residents in Gaotian Village of Liuyang City.

Gaotian, one typical conservative village in rural area of South China, is differentiated from other adjacent village for its longevity and health situation of residents. To ascertain the difference of intestinal microbial community between Gaotian and other region, high-throughput sequencing and systematical bioinformation analyses was adopted to compare 21 samples in long life group with 28 in control group. The α diversity showed that the diversity of species of intestinal flora of Gaotian villagers was higher than that of control group, while the ß diversity showed that the similarity of intestinal flora for Gaotian residents was also much higher than that of control group. OTU cluster analysis and Venn diagram showed that the intestinal microbial community of Gaotian villagers is different from that of control group. To quantitatively compare the main flora constitution in all samples, real-time PCR was performed, and the results showed that the biomass of Enterococcus, Lactobacillus, Enterobacteriaceae, Clostridium perfringens, and Bacteroides of Gaotian villages is generally significantly higher than that of control group. Remarkably, some special species, i.e., Methanobacterium, Butyricimonas, Deinococcus, and Streptococcaceae, have been found in Gaotian villagers. Overall, this study lays a preparatory basis for exploration of the resources of special species from healthy and long-living elderly Gaotian villagers and for proposal of a hypothesis, namely, the diversity in intestinal flora of Gaotian might contribute to the longevity and health of local residents. Further study should be focused on screening and functional evaluation of the special species in the long-life residents.

Rapid detection of Staphylococcus aureus in dairy and meat foods by combination of capture with silica-coated magnetic nanoparticles and thermophilic helicase-dependent isothermal amplification.

Staphylococcus aureus is one of the main pathogens in dairy and meat products; therefore, developing a highly sensitive and rapid method for its detection is necessary. In this study, a quantitative detection method for Staph. aureus was developed using silica-coated magnetic nanoparticles and thermophilic helicase-dependent isothermal amplification. First, genomic DNA was extracted from lysed bacteria using silica-coated magnetic nanoparticles and amplified using thermophilic helicase-dependent isothermal amplification. After adding the nucleic-acid dye SYBR Green I to the amplicons, the fluorescence intensity was observed using a UV lamp or recorded using a fluorescence spectrophotometer. This detection system had a detection limit of 5×10(0) cfu/mL in pure culture and milk-powder samples and 5×10(1) cfu/mL in pork samples using a UV light in less than 2h. In addition, a good linear relationship was obtained between fluorescence intensity and bacterial concentrations ranging from 10(2) to 10(4) cfu/mL under optimal conditions. Furthermore, the results from contaminated milk powder and pork samples suggested that the detection system could be used for the quantitative analysis of Staph. aureus and applied potentially to the food industry for the detection of this pathogen.

KMT-PLL: K-Means Cross-Attention Transformer for Partial Label Learning.

Partial label learning (PLL) studies the problem of learning instance classification with a set of candidate labels and only one is correct. While recent works have demonstrated that the Vision Transformer (ViT) has achieved good results when training from clean data, its applications to PLL remain limited and challenging. To address this issue, we rethink the relationship between instances and object queries to propose K-means cross-attention transformer for PLL (KMT-PLL), which can continuously learn cluster centers and be used for downstream disambiguation tasks. More specifically, K-means cross-attention as a clustering process can effectively learn the cluster centers to represent label classes. The purpose of this operation is to make the similarity between instances and labels measurable, which can effectively detect noise labels. Furthermore, we propose a new corrected cross entropy formulation, which can assign weights to candidate labels according to the instance-to-label relevance to guide the training of the instance classifier. As the training goes on, the ground-truth label is progressively identified, and the refined labels and cluster centers in turn help to improve the classifier. Simulation results demonstrate the advantage of the KMT-PLL and its suitability for PLL.

Bioinspired axial S-coordinated single-atom cobalt catalyst to efficient activate peroxymonosulfate for selective high-valent Co-Oxo species generation.

The efficient activation and selective high-valent metal-oxo (HVMO) species generation remain challenging for peroxymonosulfate (PMS)-based advanced oxidation processes (PMS-AOPs) in water purification. The underlying mechanism of the activation pathway is ambiguous, leading to a massive dilemma in the control and regulation of HVMO species generation. Herein, bioinspired by the bio-oxidase structure of cytochrome P450, the axial coordination strategy was adopted to tailor a single-atom cobalt catalyst (CoN4S-CB) with an axial S coordination. CoN4S-CB high-selectively generated high-valent Co-Oxo species (Co(IV)=O) via PMS activation. Co(IV)=O demonstrated an ingenious oxygen atom transfer (OAT) reaction to achieve the efficient degradation of sulfamethoxazole (SMX), and this allowed robust operation in various complex environments. The axial S coordination modulated the 3d orbital electron distribution of the Co atom. Density functional theory (DFT) calculation revealed that the axial S coordination decreased the energy barrier for PMS desorption and lowered the free energy change (ΔG) for Co(IV)=O generation. CoN4S-PMS* had a narrow d-band close to the Fermi level, which enhanced charge transfer to accelerate the cleavage of O-O and O-H bonds in PMS. This work provides a broader perspective on the activator design with natural enzyme structure-like active sites to efficient activate PMS for selective HVMO species generation.

High-Similarity-Pass Attention for Single Image Super-Resolution.

Recent developments in the field of non-local attention (NLA) have led to a renewed interest in self-similarity-based single image super-resolution (SISR). Researchers usually use the NLA to explore non-local self-similarity (NSS) in SISR and achieve satisfactory reconstruction results. However, a surprising phenomenon that the reconstruction performance of the standard NLA is similar to that of the NLA with randomly selected regions prompted us to revisit NLA. In this paper, we first analyzed the attention map of the standard NLA from different perspectives and discovered that the resulting probability distribution always has full support for every local feature, which implies a statistical waste of assigning values to irrelevant non-local features, especially for SISR which needs to model long-range dependence with a large number of redundant non-local features. Based on these findings, we introduced a concise yet effective soft thresholding operation to obtain high-similarity-pass attention (HSPA), which is beneficial for generating a more compact and interpretable distribution. Furthermore, we derived some key properties of the soft thresholding operation that enable training our HSPA in an end-to-end manner. The HSPA can be integrated into existing deep SISR models as an efficient general building block. In addition, to demonstrate the effectiveness of the HSPA, we constructed a deep high-similarity-pass attention network (HSPAN) by integrating a few HSPAs in a simple backbone. Extensive experimental results demonstrate that HSPAN outperforms state-of-the-art approaches on both quantitative and qualitative evaluations. Our code and a pre-trained model were uploaded to GitHub (https://github.com/laoyangui/HSPAN) for validation.