African swine fever virus pB318L, a trans-geranylgeranyl-diphosphate synthase, negatively regulates cGAS-STING and IFNAR-JAK-STAT signaling pathways.

African swine fever (ASF) is an acute, hemorrhagic, and severe infectious disease caused by the ASF virus (ASFV). ASFV has evolved multiple strategies to escape host antiviral immune responses. Here, we reported that ASFV pB318L, a trans-geranylgeranyl-diphosphate synthase, reduced the expression of type I interferon (IFN-I) and IFN-stimulated genes (ISGs). Mechanically, pB318L not only interacted with STING to reduce the translocation of STING from the endoplasmic reticulum to the Golgi apparatus but also interacted with IFN receptors to reduce the interaction of IFNAR1/TYK2 and IFNAR2/JAK1. Of note, ASFV with interruption of B318L gene (ASFV-intB318L) infected PAMs produces more IFN-I and ISGs than that in PAMs infected with its parental ASFV HLJ/18 at the late stage of infection. Consistently, the pathogenicity of ASFV-intB318L is attenuated in piglets compared with its parental virus. Taken together, our data reveal that B318L gene may partially affect ASFV pathogenicity by reducing the production of IFN-I and ISGs. This study provides a clue to design antiviral agents or live attenuated vaccines to prevent and control ASF.

Evolution and biological characterization of H5N1 influenza viruses bearing the clade 2.3.2.1 hemagglutinin gene.

H5N1 avian influenza viruses bearing the clade 2.3.2.1 hemagglutinin (HA) gene have been widely detected in birds and poultry in several countries. During our routine surveillance, we isolated 28 H5N1 viruses between January 2017 and October 2020. To investigate the genetic relationship of the globally circulating H5N1 viruses and the biological properties of those detected in China, we performed a detailed phylogenic analysis of 274 representative H5N1 strains and analyzed the antigenic properties, receptor-binding preference, and virulence in mice of the H5N1 viruses isolated in China. The phylogenic analysis indicated that the HA genes of the 274 viruses belonged to six subclades, namely clades 2.3.2.1a to 2.3.2.1f; these viruses acquired gene mutations and underwent complicated reassortment to form 58 genotypes, with G43 being the dominant genotype detected in eight Asian and African countries. The 28 H5N1 viruses detected in this study carried the HA of clade 2.3.2.1c (two strains), 2.3.2.1d (three strains), or 2.3.2.1f (23 strains), and formed eight genotypes. These viruses were antigenically well-matched with the H5-Re12 vaccine strain used in China. Animal studies showed that the pathogenicity of the H5N1 viruses ranged from non-lethal to highly lethal in mice. Moreover, the viruses exclusively bound to avian-type receptors and have not acquired the ability to bind to human-type receptors. Our study reveals the overall picture of the evolution of clade 2.3.2.1 H5N1 viruses and provides insights into the control of these viruses.

Molecular insight of dissolved organic matter and chlorinated disinfection by-products in reclaimed water during chlorination with permanganate preoxidation.

Permanganate is a common preoxidant applied in water treatment to remove organic pollutants and to reduce the formation of disinfection by-products. However, the effect of permanganate preoxidation on the transformation of dissolved effluent organic matter (dEfOM) and on the formation of unknown chlorinated disinfection by-products (Cl-DBPs) during chlorination remains unknown at molecular level. In this work, the molecular changes of dEfOM during permanganate preoxidation and subsequent chlorination were characterized using Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). Permanganate preoxidation was found to decrease the DBE (double bond equivalent) and AImod (modified aromaticity index) of the dEfOM. The identity and fate of over 400 unknown Cl-DBPs during KMnO4-chlorine treatment were investigated. Most Cl-DBPs and the precursors were found to be highly unsaturated aliphatic and phenolic compounds. The Cl-DBPs precursors with lower H/C and lower O/C were preferentially removed by permanganate preoxidation. Additionally, permanganate preoxidation decreased the number of unknown Cl-DBPs by 30% and intensity of unknown Cl-DBPs by 25%. One-chlorine-containing DBPs were the major Cl-DBPs and had more CH2 groups and higher DBEw than Cl-DBPs containing two and three chlorine atoms. 60% of the Cl-DBPs formation was attributed to substitution reactions (i.e., +Cl-H, +2Cl-2H, +3Cl-3H, +ClO-H, +Cl2O3-2H). This work provides detailed molecular level information on the efficacy of permanganate preoxidation on the control of overall Cl-DBPs formation during chlorination.

Highly Pathogenic Avian Influenza Virus (H5N1) Clade 2.3.4.4b Introduced by Wild Birds, China, 2021.

Highly pathogenic avian influenza (HPAI) subtype H5N1 clade 2.3.4.4b virus has spread globally, causing unprecedented large-scale avian influenza outbreaks since 2020. In 2021, we isolated 17 highly pathogenic avian influenza H5N1 viruses from wild birds in China. To determine virus origin, we genetically analyzed 1,529 clade 2.3.4.4b H5N1 viruses reported globally since October 2020 and found that they formed 35 genotypes. The 17 viruses belonged to genotypes G07, which originated from eastern Asia, and G10, which originated from Russia. The viruses were moderately pathogenic in mice but were highly lethal in ducks. The viruses were in the same antigenic cluster as the current vaccine strain (H5-Re14) used in China. In chickens, the H5/H7 trivalent vaccine provided complete protection against clade 2.3.4.4b H5N1 virus challenge. Our data indicate that vaccination is an effective strategy for preventing and controlling the globally prevalent clade 2.3.4.4b H5N1 virus.

Activation persulfate for efficient tetrabromobisphenol A degradation via carbon-based materials: Synergistic mechanism of doped N and Fe.

In this study, a novel carbon-based material (Fe-N-PGWBC) utilizing the garden waste, melamine and FeSO4 as the precursor was successfully synthesized, efficiently activating peroxydisulfate (PDS) to degrade tetrabromobisphenol A (TBBPA). Under typical conditions (Fe-N-PGWBC dose of 100 mg·L-1, PDS of 0.2 mM and TBBPA of 10 mg·L-1), Fe-N-PGWBC/PDS system could achieve over 99% TBBPA removal (including adsorption and degradation) within 60 min, and the corresponding rate constant ks was 0.0724 min-1, which was almost 40.2 times higher than that of the pristine biochar. The extraction experiments implied that the excellent adsorption performance of Fe-N-PGWBC did not hinder the degradation of TBBPA. Abundant active sites (rich oxygen-containing functional groups, Fe-O and Fe3C) of Fe-N-PGWBC could effectively promote PDS decomposition to produce reactive oxygen species. The probe-based kinetic modelling methods verified that approximately 87.6% TBBPA was degraded by SO4·-, 12.2% TBBPA was degraded by 1O2, and 0.2% TBBPA was degraded by ·OH. Furthermore, based on the calculation of density functional theory and identification of products, TBBPA was mainly involved in three transformation pathways including hydroxylation, debromination and ß-scission process. The study proposed a facile resource approach of garden waste and provided deeper understanding for the TBBPA degradation mechanisms in heterogeneous system.

African Swine Fever Virus HLJ/18 CD2v Suppresses Type I IFN Production and IFN-Stimulated Genes Expression through Negatively Regulating cGMP-AMP Synthase-STING and IFN Signaling Pathways.

African swine fever is a fatal infectious disease caused by African swine fever virus (ASFV). The high mortality caused by this infectious disease is a significant challenge to the swine industry worldwide. ASFV virulence is related to its ability to antagonize IFN response, yet the mechanism of antagonism is not understood. Recently, a less virulent recombinant virus has emerged that has a EP402R gene deletion within the parental ASFV HLJ/18 (ASFV-ΔEP402R) strain. EP402R gene encodes CD2v. Hence we hypothesized that ASFV uses CD2v protein to evade type I IFN-mediated innate immune response. We found that ASFV-ΔEP402R infection induced higher type I IFN response and increased the expression of IFN-stimulated genes in porcine alveolar macrophages when compared with parental ASFV HLJ/18. Consistent with these results, CD2v overexpression inhibited type I IFN production and IFN-stimulated gene expression. Mechanistically, CD2v, by interacting with the transmembrane domain of stimulator of IFN genes (STING), prevented the transport of STING to the Golgi apparatus, and thereby inhibited the cGMP-AMP synthase-STING signaling pathway. Furthermore, ASFV CD2v disrupted IFNAR1-TYK2 and IFNAR2-JAK1 interactions, and thereby inhibited JAK-STAT activation by IFN-α. In vivo, specific pathogen-free pigs infected with the mutant ASFV-ΔEP402R strain survived better than animals infected with the parental ASFV HLJ/18 strain. Consistent with this finding, IFN-ß protein levels in the peripheral blood of ASFV-ΔEP402R-challenged pigs were significantly higher than in the blood of ASFV HLJ/18-challenged pigs. Taken together, our findings suggest a molecular mechanism in which CD2v inhibits cGMP-AMP synthase-STING and IFN signaling pathways to evade the innate immune response rendering ASFV infection fatal in pigs.

Genetic analysis and biological characterization of H10N3 influenza A viruses isolated in China from 2014 to 2021.

The H10 subtypes of avian influenza viruses pose a continual threat to the poultry industry and human health. The sporadic spillover of H10 subtypes viruses from poultry to humans is represented by the H10N8 human cases in 2013 and the recent H10N3 human infection in 2021. However, the genesis and characteristics of the recent reassortment H10N3 viruses have not been systemically investigated. In this study, we characterized 20 H10N3 viruses isolated in live poultry markets during routine nationwide surveillance in China from 2014 to 2021. The viruses in the recent reassortant genotype acquired their hemagglutinin (HA) and neuraminidase (NA) genes from the duck H10 viruses and H7N3 viruses, respectively, whereas the internal genes were derived from chicken H9N2 viruses as early as 2019. Receptor-binding analysis indicated that two of the tested H10N3 viruses had a higher affinity for human-type receptors than for avian-type receptors, highlighting the potential risk of avian-to-human transmission. Animal studies showed that only viruses belonging to the recent reassortant genotype were pathogenic in mice; two tested viruses transmitted via direct contact and one virus transmitted by respiratory droplets in guinea pigs, though with limited efficiency. These findings emphasize the need for enhanced surveillance of H10N3 viruses.

H3N8 subtype avian influenza virus originated from wild birds exhibited dual receptor-binding profiles.

We present the phylogeny, receptor binding property, growth in mammal cells and pathogenicity in mammal model of H3N8 viruses, which were isolated from wild birds in China. The human receptor preference and efficient replication in mice without prior adaption highlight that the H3N8 virus possesses the public threat potential.

Comammox Nitrospira Bacteria Are Dominant Ammonia Oxidizers in Mainstream Nitrification Bioreactors Emended with Sponge Carriers.

Complete ammonia oxidation (i.e., comammox) is a newly discovered microbial process performed by a subset of the Nitrospira genus, and this unique microbial process has been ubiquitously detected in various wastewater treatment units. However, the operational conditions favoring comammox prevalence remain unclear. In this study, the dominance of comammox Nitrospira in four sponge biofilm reactors fed with low-strength ammonium (NH4+ = 23 ± 3 mg N/L) wastewater was proved by coupling 16S rRNA gene amplicon sequencing, quantitative polymerase chain reaction (qPCR), and metagenomic sequencing. The results showed that comammox Nitrospira dominated in the nitrifying guild over canonical ammonia-oxidizing bacteria (AOB) constantly, despite the significant variation in the residual ammonium concentration (0.01-15 mg N/L) under different sets of operating conditions. This result indicates that sponge biofilms greatly favor retaining comammox Nitrospira in wastewater treatment and highlights an essential role of biomass retention in the comammox prevalence. Moreover, analyses of the assembled metagenomic sequences revealed that the retrieved amoA gene sequences affiliated with comammox Nitrospira (53.9-66.0% read counts of total amoA gene reads) were always higher than those (28.4-43.4%) related to ß-proteobacterial AOB taxa. The comammox Nitrospira bacteria detected in the present biofilm systems were close to clade A Candidatus Nitrospira nitrosa.

Immobilization of hexavalent chromium in contaminated soil by nano-sized layered double hydroxide intercalated with diethyldithiocarbamate: Fraction distribution, plant growth, and microbial evolution.

Soil contamination by hexavalent chromium (Cr(VI)) poses great risks to human health and ecosystem safety. We introduced a new cheap and efficient layered double hydroxide intercalated with diethyldithiocarbamate (DDTC-LDH) for in-situ remediation of Cr(VI)-contaminated soil. The content of Cr(VI) in contaminated soil (134.26 mg kg-1) was rapidly reduced to 1.39 mg kg-1 within 10 days by 0.5% of DDTC-LDH. This result attains to or even exceeds the effectiveness of most of reported soil amendments for Cr(VI) removal in soils. The production cost of DDTC-LDH ($4.02 kg-1) was relatively low than some common materials, such as nano zero-valent iron ($22.80-140.84 kg-1). The growth of water spinach became better with the increase of DDTC-LDH dose from 0% to 0.5%, suggesting the recovery of soil function. DDTC-LDH significantly altered the structure and function of soil microbial communities. The species that have Cr(VI)-resistant or Cr(VI)-reductive ability were enriched in DDTC-LDH remediated soils. Network analysis revealed a significant functional niche differentiation of soil microbial communities. In addition to the enhancement of Cr(VI) reduction, the stimulation of plant growth promoting traits, including siderophore biosynthesis, oxidation resistance to reactive oxygen species, and phosphorus availability by DDTC-LDH was another essential mechanism for the immediate remediation of Cr(VI)-contaminated soil.

Novel co-polymerization of polypyrrole/polyaniline on ferrate modified biochar composites for the efficient adsorption of hexavalent chromium in water.

It is still a huge challenge to prepare cheap and effective composite materials for removing hexavalent chromium (Cr(VI)) in sewage treatment. In this study, a noval co-polymerization of polypyrrole/polyaniline on ferrate modified biochar (Ppy/PANI/FBC) was fabricated via ferrate-promoted pyrolysis and in-situ oxidative polymerization of pyrrole and aniline molecules to effectively remove Cr(VI) from polluted water. The Ppy/PANI/FBC quickly decreased Cr(VI) concentration from 38.92 to 3.92 mg/L within 400 min, with an efficient removal efficiency (89.92%), which was significantly higher than that of FBC (4.75%), Ppy/FBC (72.30%), and PANI/FBC (42.43%). These results are mainly caused by its conjugated connection and well-dispersion of Ppy and PANI on the surface of a carbon-based material. Meanwhile, the experimental results were in line with the pseudo-second-order kinetic and Freundlich models. The Ppy/PANI/FBC is featured by a high capacity of Cr(VI) adsorption (up to 203.71 mg/g). In addition, it could be adopted for efficiently removing Cr(VI) over a wide pH range (4-9) because of the positively charged nitrogen (-NH.+- and = N+-). The sorption mechanisms of Cr(VI) were identified, including electrostatic interaction with surface protonated nitrogen (N+), ion exchange between the doped Cl- ions and Cr(VI), chemical decrease of the Cr(VI) to Cr(III) by the iron valence cycle and efficient electron transfer of Ppy/PANI/FBC, as well as surface complexation by amine and oxygen-containing groups. More importantly, 97.98% Cr(VI) was efficiently removed in 20 min by coupling a photocatalytic reaction, also providing a novel idea for the practical use of adsorbents in wastewater treatment.

Synergistic ammonia and nitrate removal in a novel pyrite-driven autotrophic denitrification biofilter.

Pyrite is one kind of cost-effective electron donors for nitrate denitrification. In this study, a pyrite-driven autotrophic denitrification biofilter was applied for simultaneous removal of NH4+ and NO3- over the 150-day. The influent NH4+/NO3- ratio (0.3-1.7) had less effect on system performance, while for the hydraulic retention times (HRTs, 24-3 h), the removal percentage of both > 90% and removal loading rates of 52.8 and 59.4 mg N/(L·d) for NH4+ and NO3- removal were obtained at the HRT of 6 h. The 16S rRNA genes analysis showed that Ferritrophicum, Thiobacillus, Candidatus_Brocadia, and unidentified_Nitrospiraceae were predominant. Analyses of nitrogen and sulfur metabolism showed that ammonia was removed by complete nitrification, nitrate was reduced to N2, and sulfide was oxidized to sulfate. Dynamics of pollutants within the reactor and microbial activity showed nitrification/Anammox and pyrite-driven autotrophic denitrification were responsible for the synergistic removal of NH4+/NO3- in this system.

H7N9 virus infection triggers lethal cytokine storm by activating gasdermin E-mediated pyroptosis of lung alveolar epithelial cells.

The H7N9 influenza virus emerged in China in 2013, causing more than 1560 human infections, 39% of which were fatal. A 'cytokine storm' in the lungs of H7N9 patients has been linked to a poor prognosis and death; however, the underlying mechanism that triggers the cytokine storm is unknown. Here, we found that efficient replication of the H7N9 virus in mouse lungs activates gasdermin E (GSDME)-mediated pyroptosis in alveolar epithelial cells, and that the released cytosolic contents then trigger a cytokine storm. Knockout of Gsdme switched the manner of death of A549 and human primary alveolar epithelial cells from pyroptosis to apoptosis upon H7N9 virus infection, and Gsdme knockout mice survived H7N9 virus lethal infection. Our findings reveal that GSDME activation is a key and unique mechanism for the pulmonary cytokine storm and lethal outcome of H7N9 virus infection and thus opens a new door for the development of antivirals against the H7N9 virus.

Characterization of nitrosamines and nitrosamine precursors as non-point source pollutants during heavy rainfall events in an urban water environment.

N-nitrosodimethylamine (NDMA) and N-nitrosomorpholine (NMOR) and their specific precursors (N,N-dimethylformamide [DMF] for NDMA and morpholine [MOR] for NMOR) were widely identified in runoff of urban area around the southern Lake Biwa basin, Japan. It was thought that this runoff might constitute a non-point source of the four compounds in rivers and sewage treatment plants (STPs) during heavy rainfall events. We investigated the spatiotemporal patterns of NDMA, NMOR, DMF and MOR in runoff and rivers in rainy days. NDMA and NMOR were detected in concentrations of up to 295 ng/L, while DMF and MOR were detected in concentrations of up to 33.7 µg/L. Continuous sequential sampling over periods of 24 or 48 h at the largest STP in the study area revealed that the four compounds in the primary effluent (PE) each had higher mass fluxes during heavy rainfall events than on dry days. This phenomenon might be contributed to non-point sources (e.g., runoff) from infiltration/inflow related to rainwater into sanitary sewers. Moreover, the four compounds were confirmed to have higher mass fluxes in the final effluent of the STP during periods of PE bypass (1.3-1.7 times for NDMA, NMOR, and MOR; over 200 times for DMF; on average) than that on dry days because of increasing inflow during heavy rain than during periods without PE bypass in dry weather.

Microbial investigations of new hydrogel-biochar composites as soil amendments for simultaneous nitrogen-use improvement and heavy metal immobilization.

Agricultural sustainability is challenging because of increasingly serious and co-existing issues, e.g., poor nitrogen-fertilizer use and heavy metal pollution. Herein, we introduced a new poly(acrylic acid)-grafted chitosan and biochar composite (PAA/CTS/BC) for soil amendment, and provided a first microbial insight into how PAA/CTS/BC amendment simultaneously improved nitrogen cycling and immobilized heavy metals. Our results suggest that the PAA/CTS/BC amendment significantly promoted soil ammonium retention, and reduced nitrate accumulation, nitrous oxide emission and ammonia volatilization during the rice cultivation. The availability of various heavy metals (Fe, Mn, Cu, Zn, Ni, Pb, Cr, and As) markedly decreased in the PAA/CTS/BC amended soil, thereby reducing their accumulation in rice root. The PAA/CTS/BC amendment significantly altered the structure and function of soil microbial communities. Importantly, the co-occurrence networks of microbial communities became more complex and function-specific after PAA/CTS/BC addition. For example, the keystone species related to organic matter degradation, denitrification, and plant resistance to pathogen or stresses were enriched within the network. In addition to direct adsorption, the effects of PAA/CTS/BC on shaping microbial communities played dominant roles in the soil amendment. Our findings provide a promising strategy of simultaneous nitrogen-use improvement and heavy metal immobilization for achieving crop production improvement, pollution control, and climate change mitigation.

Citrate-modified biochar for simultaneous and efficient plant-available silicon release and copper adsorption: Performance and mechanisms.

Silicon (Si) deficiency and heavy metals (HMs) pollution are common for farmland soil because of long-term intensive farming. In this study, a novel citrate-modified biochar (C-BC) was introduced as a soil conditioner to simultaneously increase the amount of plant-available Si (PASi) and immobilize HMs. The maximum amount of PASi released was 33.00 mg⋅g-1 from C-BC pre-treated with 0.1 mol⋅L-1 citrate (C-BC0.1). A formation-transport coupling mechanism for increasing the amount of PASi released was developed. Stable Si in the biomass was pyrolyzed to give silicate that was relatively mobile via nucleophilic attack of citrate and hydrolysis of amorphous Si. Silicate species were then released through the porous surface and widening cracks caused by pyrolysis. At citrate concentrations >0.1 mol⋅L-1, the surface and cracks were easily blocked by precipitates formed during pyrolysis. The ability of C-BC to remove HMs was assessed using Cu as an example. C-BC0.1 was optimal for adsorbing Cu, and the maximum adsorption capacity was 271.73 mg⋅g-1. The Cu adsorption mechanism mainly involved surface precipitation, surface complexation, electrostatic attraction and hydrogen bonding. Our research provides important implications for simultaneously addressing Si deficiency and HMs contaminant problems by these materials for soil amendment in agro-ecosystem.

Adsorption and photocatalysis removal of arsenite, arsenate, and hexavalent chromium in water by the carbonized composite of manganese-crosslinked sodium alginate.

The preparation of easily synthesized and cheap composite materials for the efficient removal of toxic oxoanions still remains challenging in sewage treatment. Herein, a new carbonized manganese-crosslinked sodium alginate (Mn/SA-C) was fabricated for the removal of arsenite (As(III)), arsenate (As(V)) and hexavalent chromium (Cr(VI)) in water. The results indicated that the Mn/SA-C pretreated with MnSO4 solution (Mn/SA-C-S) exhibited a rapid adsorption toward As(III) and As(V) with the removal efficiency of >98% within 10 min, and had a high adsorption capacity toward As(III), As(V), and Cr(VI) with the maximum value of 189.29, 193.29, and 104.50 mg/g based on the Langmuir model, respectively. The removal efficiency of As(III), As(V), and Cr(VI) could be further significantly enhanced by coupling a photocatalytic process. For example, the time in which >98% of Cr(VI) (10 mg/L) was removed dramatically shortened from 360 min (adsorption) to 45 min (adsorption-photocatalysis), and the removal efficiency of As(III) increased by ∼10% within initial 5 min. This was primarily attributed to the Mn-catalyzed production of the photocatalytic excitons for Cr(VI) reduction, and the superoxide (•O2-) and hydroxyl (•OH) radicals for As(III) oxidation. The adsorption removal of arsenic (As) was primarily ascribed to surface complexation with MnO and precipitation by MnS2, and oxidative adsorption because of Mn valence cycle. The removal mechanisms of Cr(VI) mainly contained reduction by MnO and MnS2, complexation with MnO and carboxyl/hydroxyl groups as well as Cr(OH)3 precipitation. Our research provides a promising Mn/SA-C-S material for rapid and efficient removal of As(III), As(V), and Cr(VI) in contaminated water through an adsorption-photocatalysis synergistic strategy.

Synergistic effects of ozone/peroxymonosulfate for isothiazolinone biocides degradation: Kinetics, synergistic performance and influencing factors.

Synergistic effects of ozone (O3) and peroxymonosulfate (PMS, HSO5-) for isothiazolinone biocides degradation was studied. The synergistic ozonation process (O3/PMS) increased the efficiency of methyl-isothiazolinone (MIT) and chloro-methyl-isothiazolinone (CMIT) degradation to 91.0% and 81.8%, respectively, within 90 s at pH 7.0. This is 30.6% and 62.5% higher than the corresponding ozonation efficiency, respectively. Total radical formation value (Rct,R) for the O3/PMS process was 24.6 times that of ozonation alone. Calculated second-order rate constants for the reactions between isothiazolinone biocides and (kSO4-,MIT and kSO4-,CMIT) were 8.15 × 109 and 4.49 × 109 M-1 s-1, respectively. Relative contributions of O3, hydroxyl radical (OH) and oxidation to MIT and CMIT removal were estimated, which were 15%, 45%, and 40% for O3, OH and oxidation to MIT, and 1%, 67%, and 32% for O3, OH and oxidation to CMIT at pH 7.0, respectively. Factors influencing the O3/PMS process, namely the solution pH, chloride ions (Cl-), and bicarbonate (HCO3-), were evaluated. Increasing the solution pH markedly accelerated O3 decay and OH and formation, thus weakening the relative contribution of O3 oxidation while enhancing that of OH and . Cl- had a negligible effect on MIT and CMIT degradation. Under the dual effect of bicarbonate (HCO3-) as inhibitor and promoter, low concentrations (1-2 mM) of bicarbonate weakly promoted MIT and CMIT degradation, while high concentrations (10-20 mM) induced strong inhibition. Lastly, oxidation performance of O3 and O3/PMS processes for MIT and CMIT degradation in different water matrices was compared.

Genotype I African swine fever viruses emerged in domestic pigs in China and caused chronic infection.

The Georgia-07-like genotype II African swine fever virus (ASFV) with high virulence has been prevalent in China since 2018. Here, we report that genotype I ASFVs have now also emerged in China. Two non-haemadsorbing genotype I ASFVs, HeN/ZZ-P1/21 and SD/DY-I/21, were isolated from pig farms in Henan and Shandong province, respectively. Phylogenetic analysis of the whole genome sequences suggested that both isolates share high similarity with NH/P68 and OURT88/3, two genotype I ASFVs isolated in Portugal in the last century. Animal challenge testing revealed that SD/DY-I/21 shows low virulence and efficient transmissibility in pigs, and causes mild onset of infection and chronic disease. SD/DY-I/21 was found to cause necrotic skin lesions and joint swelling. The emergence of genotype I ASFVs will present more problems and challenges for the control and prevention of African swine fever in China.

Replication, pathogenicity, and transmission of SARS-CoV-2 in minks.

Minks are raised in many countries and have transmitted severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) to humans. However, the biologic properties of SARS-CoV-2 in minks are largely unknown. Here, we investigated and found that SARS-CoV-2 replicates efficiently in both the upper and lower respiratory tracts, and transmits efficiently in minks via respiratory droplets; pulmonary lesions caused by SARS-CoV-2 in minks are similar to those seen in humans with COVID-19. We further found that a spike protein-based subunit vaccine largely prevented SARS-CoV-2 replication and lung damage caused by SARS-CoV-2 infection in minks. Our study indicates that minks are a useful animal model for evaluating the efficacy of drugs or vaccines against COVID-19 and that vaccination is a potential strategy to prevent minks from transmitting SARS-CoV-2.