Integration of anaerobic digestion and electrodialysis for methane yield promotion and in-situ ammonium recovery

Ammonia inhibition is a common issue encountered in anaerobic digestion (AD) when treating nitrogen-rich substrates. This study proposed a novel approach, the electrodialysis-integrated AD (ADED) system, for in-situ recovery of ammonium (NH4+) while simultaneously enhancing AD performance. The ADED reactor was operated at two different NH4+-N concentrations (5,000 mg/L and 10,000 mg/L) to evaluate its performance against a conventional AD reactor. The results indicate that the ADED technology effectively reduced the NH4+-N concentration to below 2,000 mg/L, achieving this with a competitive energy consumption. Moreover, the ADED reactor demonstrated a 1.43-fold improvement in methane production when the influent NH4+-N was 5,000 mg/L, and it effectively prevented complete inhibition of methane production at the influent NH4+-N of 10,000 mg/L. The life cycle impact assessment reveals that ADED technology offers a more environmentally friendly alternative by recovering valuable fertilizer from the AD system.

Nitrate Chemodenitrification by Iron Sulfides to Ammonium under Mild Conditions and Transformation Mechanism

Autotrophic denitrification utilizing iron sulfides as electron donors has been well studied, but the occurrence and mechanism of abiotic nitrate (NO3-) chemodenitrification by iron sulfides have not yet been thoroughly investigated. In this study, NO3- chemodenitrification by three types of iron sulfides (FeS, FeS2, and pyrrhotite) at pH 6.37 and ambient temperature of 30 °C was investigated. FeS chemically reduced NO3- to ammonium (NH4+), with a high reduction efficiency of 97.5% and NH4+ formation selectivity of 82.6%, but FeS2 and pyrrhotite did not reduce NO3- abiotically. Electrochemical Tafel characterization confirmed that the electron release rate from FeS was higher than that from FeS2 and pyrrhotite. Quenching experiments and density functional theory calculations further elucidated the heterogeneous chemodenitrification mechanism of NO3- by FeS. Fe(II) on the FeS surface was the primary site for NO3- reduction. FeS possessing sulfur vacancies can selectively adsorb oxygen atoms from NO3- and water molecules and promote water dissociation to form adsorbed hydrogen, thereby forming NH4+. Collectively, these findings suggest that the NO3- chemodenitrification by iron sulfides cannot be ignored, which has great implications for the nitrogen, sulfur, and iron cycles in soil and water ecosystems.

Study of association between corneal shape parameters and axial length elongation during orthokeratology using image-pro plus software

BACKGROUND

The aim was to validate the correlation between corneal shape parameters and axial length growth (ALG) during orthokeratology using Image-Pro Plus (IPP) 6.0 software.

METHODS

This retrospective study used medical records of myopic children aged 8-13 years (n = 104) undergoing orthokeratology. Their corneal topography and axial length were measured at baseline and subsequent follow-ups after lens wear. Corneal shape parameters, including the treatment zone (TZ) area, TZ diameter, TZ fractal dimension, TZ radius ratio, eccentric distance, pupil area, and pupillary peripheral steepened zone(PSZ) area, were measured using IPP software. The impact of corneal shape parameters at 3 months post-orthokeratology visit on 1.5-year ALG was evaluated using multivariate linear regression analysis.

RESULTS

ALG exhibited significant associations with age, TZ area, TZ diameter, TZ fractal dimension, and eccentric distance on univariate linear regression analysis. Multivariate regression analysis identified age, TZ area, and eccentric distance as significantly correlated with ALG (all P < 0.01), with eccentric distance showing the strongest correlation (β = -0.370). The regressive equation was y = 1.870 - 0.235a + 0.276b - 0.370c, where y represents ALG, a represents age, b represents TZ area, and c represents eccentric distance; R2 = 0.27). No significant relationships were observed between the TZ radius ratio, pupillary PSZ area, and ALG.

CONCLUSIONS

IPP software proves effective in capturing precise corneal shape parameters after orthokeratology. Eccentric distance, rather than age or the TZ area, significantly influences ALG retardation.

Farmland Microhabitat Mediated by a Residual Microplastic Film: Microbial Communities and Function

How the plastisphere mediated by the residual microplastic film in farmlands affects microhabitat systems is unclear. Here, microbial structure, assembly, and biogeochemical cycling in the plastisphere and soil in 33 typical farmland sites were analyzed by amplicon sequencing of 16S rRNA genes and ITS and metagenome analysis. The results indicated that residual microplastic film was colonized by microbes, forming a unique niche called the plastisphere. Notable differences in the microbial community structure and function were observed between soil and plastisphere. Residual microplastic film altered the microbial symbiosis and assembly processes. Stochastic processes significantly dominated the assembly of the bacterial community in the plastisphere and soil but only in the plastisphere for the fungal community. Deterministic processes significantly dominated the assembly of fungal communities only in soil. Moreover, the plastisphere mediated by the residual microplastic film acted as a preferred vector for pathogens and microorganisms associated with plastic degradation and the nitrogen and sulfur cycle. The abundance of genes associated with denitrification and sulfate reduction activity in the plastisphere was pronouncedly higher than that of soil, which increase the potential risk of nitrogen and sulfur loss. The results will offer a scientific understanding of the harm caused by the residual microplastic film in farmlands.

Deciphering anaerobic ethanol metabolic pathways shaped by operational modes

Efficient anaerobic digestion requires the syntrophic cooperation among diverse microorganisms with various metabolic pathways. In this study, two operational modes, i.e., the sequencing batch reactor (SBR) and the continuous-flow reactor (CFR), were adopted in ethanol-fed systems with or without the supplement of powdered activated carbon (PAC) to examine their effects on ethanol metabolic pathways. Notably, the operational mode of SBR and the presence of CO2 facilitated ethanol metabolism towards propionate production. This was further evidenced by the dominance of Desulfobulbus, and the increased relative abundances of enzymes (EC: 1.2.7.1 and 1.2.7.11) involved in CO2 metabolism in SBRs. Moreover, SBRs exhibited superior biomass-based rates of ethanol degradation and methanogenesis, surpassing those in CFRs by 53.1% and 22.3%, respectively. Remarkably, CFRs with the extended solids retention time enriched high relative abundances of Geobacter of 71.7% and 70.4% under conditions with and without the addition of PAC, respectively. Although both long-term and short-term PAC additions led to the increased sludge conductivity and a reduced methanogenic lag phase, only the long-term PAC addition resulted in enhanced rates of ethanol degradation and propionate production/degradation. The strategies by adjusting operational mode and PAC addition could be adopted for modulating the anaerobic ethanol metabolic pathway and enriching Geobacter.

17β-estradiol (E2) removal in anode-electrodialysis (anode-ED) during nutrient recovery from pig manure digestate

Nutrient recovery from anaerobic digestate through electrodialysis technology (ED) has been investigated and shown high promise, but the removal of 17β-estradiol (E2), which is a natural estrogen and widely found in manure digestate, is not clear. This study examined the mechanism of membrane adsorption and anodic oxidation of E2 during recovering nutrient from manure digestate, and further investigated the performance of Anode-ED in E2 removal. The results showed that the removal of E2 in conventional ED was primarily attributed to membrane adsorption, resulting in no detectable E2 in the product solution. The adsorption capacity of the anion exchange membrane for E2 was significantly higher compared to that of the cation exchange membrane. During Anode-ED operation, E2 was efficiently removed by electrochemical oxidation, in which the chlorination played a primary role. Moreover, the oxidation intermediates of E2 were further removed after 40 min. Even though the carbonate, volatile fatty acid (VFA), and humic acid in the real wastewater have a negative impact on E2 oxidation, the E2 was completely removed from digestate during nutrient recovery in the anode-ED. This study indicates that anode-ED is a promising technology for the removal of E2 during nutrient recovery from digestate.

New insights into syntrophic ethanol oxidation: Effects of operational modes and solids retention times

Anaerobic ethanol oxidation relies on syntrophic interactions among functional microorganisms to become thermodynamically feasible. Different operational modes (sequencing batch reactors, SBRs, and continuous flow reactors, CFRs) and solids retention times (SRT, 25 days and 10 days) were employed in four ethanol-fed reactors, named as SBR25d, SBR10d, CFR25d, and CFR10d, respectively. System performance, syntrophic relationships, microbial communities, and metabolic pathways were examined. During the long-term operation, 2002.7 ± 56.0 mg COD/L acetate was accumulated in CFR10d due to the washout of acetotrophic methanogens. Microorganisms with high half-saturation constants were enriched in reactors of 25-day SRT. Moreover, ethanol oxidizing bacteria and acetotrophic methanogens with high half-saturation constants could be acclimated in SBRs. In SBRs, Syner-01 and Methanothrix dominated, and the low SRT of 10 days increased the relative abundance of Geobacter to 38.0%. In CFRs, the low SRT of 10 days resulted in an increase of Desulfovibrio among syntrophic bacteria, and CFR10d could be employed in enriching hydrogenotrophic methanogens like Methanobrevibacter.

Nitrate removal in iron sulfide-driven autotrophic denitrification biofilter: Biochemical and chemical transformation pathways and its underlying microbial mechanism

Iron sulfides-based autotrophic denitrification (IAD) is effective for treating nitrate-contaminated wastewater. However, the complex nitrate transformation pathways coupled with sulfur and iron cycles in IADs are still unclear. In this study, two columns (abiotic vs biotic) with iron sulfides (FeS) as the packing materials were constructed and operated continuously. In the abiotic column, FeS chemically reduced nitrate to ammonium under the ambient condition; this chemical reduction reaction pathway was spontaneous and has been overlooked in IAD reactors. In the biotic column (IAD biofilter), the complex nitrogen-transformation network was composed of chemical reduction, autotrophic denitrification, dissimilatory nitrate reduction to ammonium (DNRA) and sulfate reducing ammonium oxidation (Sulfammox). Metagenomic analysis and XPS characterization of the IAD biofilter further validated the roles of functional microbial communities (e.g., Acidovorax, Diaphorobacter, Desulfuromonas) in nitrate reduction process coupled with iron and sulfur cycles. This study gives an in-depth insight into the nitrogen transformations in IAD system and provides fundamental evidence about the underlying microbial mechanism for its further application in biological nitrogen removal.

Role of suspended solids on the co-precipitation of pathogenic indicators and antibiotic resistance genes with struvite from digested swine wastewater

Struvite recovered from wastewater contains high concentration of fecal indicator bacteria (FIB), porcine adenoviruses (PAdV) and antibiotic resistance genes (ARGs), becoming potential resources of these microbial hazards. Understanding the precipitation behavior of pathogenic indicators and ARGs with suspended solids (SS) will provide the possible strategy for the control of co-precipitation. In this study, SS was divided into high-density SS (separated by centrifugation) and low-density SS (further separated by filtration), and the role of SS on the co-precipitation of FIB, PAdV and ARGs was investigated. The distribution analysis showed that 35.5-73.0% FIB, 79.6% PAdV and 64.5-94.8% ARGs existed in high-density SS, while the corresponding values were 26.9-64.4%, 11.7% and 3.5-24.3% in low-density SS. During struvite generation, 82.7-96.9% FIB, 75.5% PAdV and 56.3-86.5% ARGs were co-precipitated into struvite. High-density SS contributed 20.7-68.5% FIB, 63.9% PAdV and 38.7-87.2% ARGs co-precipitation, and the corresponding contribution of low-density SS was 31.4-79.2%, 3.9% and 6.2-54.7%. Moreover, the precipitated SS in struvite obviously decreased inactivation efficiency of FIB and ARGs in drying process. These results provide a potential way to control the co-precipitation and inactivation of FIB, PAdV and ARGs in struvite through removing high-density SS prior to struvite recovery.

Development of LOX-1 Antibody Modified Immuno-liposomes as Drug Carriers to Macrophages in Atherosclerotic Lesions

We developed a drug delivery system for atherosclerotic lesions using immuno-liposomes. We focused on enhancing the delivery efficiency of the liposomes to macrophages in atherosclerotic lesions by antibody modification of lectinlike oxidized low-density lipoproteins (LDL) receptor 1 (LOX-1). The cellular accumulation of the liposomes in foam cells induced by oxidized LDL (oxLDL) in Raw264 mouse macrophages was evaluated. The cellular accumulation of LOX-1 antibody modified liposomes in oxLDL-induced foam cells and untreated Raw264 cells was significantly higher compared with that of unmodified liposomes. The liposomes were also administered intravenously to Apoeshl mice as an atherosclerosis model. Frozen sections were prepared from the mouse aortas and observed by confocal laser microscopy. The distribution of LOX-1 antibody modified liposomes in the atherosclerotic regions of Apoeshl mice was significantly greater compared with that of unmodified liposomes. The results suggest that LOX-1 antibody modified liposomes can target foam cells in atherosclerotic lesions, providing a potential route for delivering various drugs with pharmacological effects or detecting atherosclerotic foci for the diagnosis of atherosclerosis.

Industrial-scale composting of swine manure with a novel additive-yellow phosphorus slag: Variation in maturity indicators, compost quality and phosphorus speciation

Composting experiment of swine manure, adding with yellow phosphorus slag(YPS) at 5% (w/w), was conducted in an industrial-scale reactor covered with semi-permeable membrane. During 27 days of composting, the changes in temperature, compost quality and phosphorus(P) speciation of products were monitored. Results indicated that the temperature of compost pile was sharply increased on day 2, and the thermophilic period lasted for 15 days. The dynamics in germination index(GI), pH, nutrient contents, etc. of products were in line with conventional composting process. For P distribution, the contents of total-P and citric acid extracted-P(CAP) of products were increased during composting, while that of Olsen-P was decreased. HCl extracted inorganic P(HCl-Pi), a slowly release fraction of P, was dominated in the product, which showed an increasing trend during the composting. These results suggest that the industrial-scale composting with novel YPS additive can be accomplished, and its product contains abundant slowly released P.

Co-precipitation of heavy metals with struvite from digested swine wastewater: Role of suspended solids

Struvite production can recover ammonia and phosphorous from digested wastewater as fertilizer. During struvite generation, most of the heavy metals was co-precipitated with ammonia and phosphorous into struvite. Understanding the precipitation behavior of heavy metals with suspended solids (SS) might provide the possible strategy for the control of co-precipitation. In this study, the distribution of heavy metals in SS and their role on the co-precipitation during struvite recovery from digested swine wastewater were investigated. The results showed that the concentration of heavy metal (including Mn, Zn, Cu, Ni, Cr, Pb and As) ranged from 0.05 to 17.05 mg/L in the digested swine wastewater. The distribution analysis showed that SS with particles > 50 μm harbored most of individual heavy metal (41.3-55.6%), followed by particles 0.45-50 μm (20.9-43.3%), and SS-removed filtrate (5.2-32.9%). During struvite generation, 56.9-80.3% of individual heavy metal was co-precipitated into struvite. The contributions of SS with particles > 50 μm, 0.45-50 μm, and SS-removed filtrate on the individual heavy metal co-precipitation were 40.9-64.3%, 25.3-48.3% and 1.9-22.9%, respectively. These finding provides potential way for controlling the co-precipitation of heavy metals in struvite.

High-rate iron sulfide and sulfur-coupled autotrophic denitrification system: Nutrients removal performance and microbial characterization

Iron sulfides-based autotrophic denitrification (IAD) is a promising technology for nitrate and phosphate removal from low C:N ratio wastewater due to its cost-effectiveness and low sludge production. However, the slow kinetics of IAD, compared to other sulfur-based autotrophic denitrification (SAD) processes, limits its engineering application. This study constructed a co-electron-donor (FeS and S⁰ with a volume ratio of 2:1) iron sulfur autotrophic denitrification (ISAD) biofilter and operated at as short as 1 hr hydraulic retention time (HRT). Long-term operation results showed that the superior total nitrogen and phosphate removals of the ISAD biofilter were 90-100% at 1-12 h HRT, with the highest denitrification rate up to 960 mg/L/d. Considering low sulfate production, HRT of 3 h could be the optimal condition. Such superior performance in the ISAD biofilter was achieved due to the interactions between FeS and S⁰, which accelerated the denitrification process and maintained the acidity-alkalinity balance. Metagenomic analysis found that the enriched nitrate-dependent iron-oxidizing (NDFO) bacteria (Acinetobacter and Acidovorax), sulfur-oxidizing bacteria (SOB), and dissimilatory nitrate reduction to ammonia (DNRA) bacteria likely supported stable nitrate reduction. The metabolic pathway analysis showed that completely denitrification and DNRA, coupled with sulfur oxidation, disproportionation, iron oxidation and phosphate precipitation with FeS and S⁰ as co-electron donors, were responsible for the high-rate nitrate and phosphate removal. This study provides the potential of ISAD as a highly efficient post-denitrification technology and sheds light on the balanced microbial S-N-Fe transformation.

Ca(ClO)2 pretreatment enhancing suspended solids removal through flocculation from digested dairy wastewater and its mechanisms

Intensive animal farming produces large volume of digested liquid, and overdose application often causes the pollution of surface water and groundwater. Therefore, post-treatment is very necessary for the discharging of surplus digested liquid, but the removal of high concentrations of suspended solids (SS) in the digested liquid is a challenge. In this study, the effect of Ca(ClO)₂ pretreatment on SS flocculation removal of digested dairy wastewater was investigated. The results showed that, without Ca(ClO)₂ pretreatment, the flocculation by polyacrylamide (PAM), polyferric sulfate (PFS) or polymeric aluminum chloride (PAC) only removed 42.6 %-50.4 % SS from anaerobic digested liquid. With the combination of Ca(ClO)₂ pretreatment and PAC flocculation together, the SS removal efficiency can reach 80 %. The total chemical oxygen demand (TCOD) removal had a similar trend with SS removal, but soluble chemical oxygen demand (SCOD) removal was less affected by the pretreatment and flocculation. More than 75 % of orthophosphate (SRP) and total soluble phosphorus (TSP) was removed after Ca(ClO)₂ pretreatment and flocculation with PFS or PAC. Ca(ClO)₂ pretreatment also effectively inactivated fecal bacteria. The mechanisms of Ca(ClO)₂ pretreatment enhancing SS flocculation removal were further elucidated. The SS removal was the action of ClO^- and Ca²⁺ together. The function of ClO^- was to break down suspended particles, change the surface, and decrease the absolute Zeta potential, while the function of Ca²⁺ was to form precipitation. This result indicates that Ca(ClO)₂ pretreatment can effectively enhance the SS flocculation removal of anaerobic digested liquid.

Role of iron(II) sulfide in autotrophic denitrification under tetracycline stress: Substrate and detoxification effect

Autotrophic denitrification using inorganic compounds as electron donors has gained increasing attention in the field of wastewater treatment due to its numerous advantages, such as no need for exogenous organic carbon, low energy input, and low sludge production. Tetracycline (TC), a refractory contaminant, is often found coexisting with nutrients (NO₃^- and PO₄^3-) in wastewater, which can negatively affect the biological nutrient removal process because of its biological toxicity. However, the performance of autotrophic denitrification under TC stress has rarely been reported. In this study, the effects of TC on autotrophic denitrification with thiosulfate (Na₂S₂O₃) and iron (II) sulfide (FeS) as the electron donors were investigated. With Na₂S₂O₃ as the electron donor, TC slowed down the nitrate removal rate, which decreased from 1.32 to 0.18 d^-1, when TC concentration increased from 0 mg/L to 50 mg/L. When TC concentration was higher than 2 mg/L, nitrite reduction was seriously inhibited, leading to nitrite accumulation. With FeS as the electron donor, nitrate removal was much more efficient under TC-stressed conditions, and no distinct nitrite accumulation was observed when the initial TC concentration was as high as 10 mg/L, indicating the effective detoxification of FeS. The detoxification effects in the FeS autotrophic denitrification system mainly resulted from the rapid adsorption of TC by FeS and effective degradation of TC, as proven by a relatively higher living biomass area. This study offers new insights into the response of sulfur-based autotrophic denitrifiers to TC stress and demonstrates that the FeS-based autotrophic denitrification process is a promising technology for the treatment of wastewater containing emerging contaminants and nutrients.

Systematic Analysis of Mobile Genetic Elements Mediating β-Lactamase Gene Amplification in Noncarbapenemase-Producing Carbapenem-Resistant Enterobacterales Bloodstream Infections

Noncarbapenemase-producing carbapenem-resistant Enterobacterales (non-CP-CRE) are increasingly recognized as important contributors to prevalent carbapenem-resistant Enterobacterales (CRE) infections. However, there is limited understanding of mechanisms underlying non-CP-CRE causing invasive disease. Long- and short-read whole-genome sequencing was used to elucidate carbapenem nonsusceptibility determinants in Enterobacterales bloodstream isolates at MD Anderson Cancer Center in Houston, Texas. We investigated carbapenem nonsusceptible Enterobacterales (CNSE) mechanisms (i.e., isolates with carbapenem intermediate resistance phenotypes or greater) through a combination of phylogenetic analysis, antimicrobial resistance gene detection/copy number quantification, porin assessment, and mobile genetic element (MGE) characterization. Most CNSE isolates sequenced were non-CP-CRE (41/79; 51.9%), whereas 25.3% (20/79) were Enterobacterales with intermediate susceptibility to carbapenems (CIE), and 22.8% (18/79) were carbapenemase-producing Enterobacterales (CPE). Statistically significant copy number variants (CNVs) of extended-spectrum β-lactamase (ESBL) genes (Wilcoxon Test; P-value < 0.001) were present in both non-CP-CR E. coli (median CNV = 2.6×; n = 17) and K. pneumoniae (median CNV = 3.2×, n = 17). All non-CP-CR E. coli and K. pneumoniae had predicted reduced expression of at least one outer membrane porin gene (i.e., ompC/ompF or ompK36/ompK35). Completely resolved CNSE genomes revealed that IS26 and ISEcp1 structures harboring blaCTX-M variants along with other antimicrobial resistance elements were associated with gene amplification, occurring in mostly IncFIB/IncFII plasmid contexts. MGE-mediated β-lactamase gene amplifications resulted in either tandem arrays, primarily mediated by IS26 translocatable units, or segmental duplication, typically due to ISEcp1 transposition units. Non-CP-CRE strains were the most common cause of CRE bacteremia with carbapenem nonsusceptibility driven by concurrent porin loss and MGE-mediated amplification of blaCTX-M genes. IMPORTANCE Carbapenem-resistant Enterobacterales (CRE) are considered urgent antimicrobial resistance (AMR) threats. The vast majority of CRE research has focused on carbapenemase-producing Enterobacterales (CPE) even though noncarbapenemase-producing CRE (non-CP-CRE) comprise 50% or more of isolates in some surveillance studies. Thus, carbapenem resistance mechanisms in non-CP-CRE remain poorly characterized. To address this problem, we applied a combination of short- and long-read sequencing technologies to a cohort of CRE bacteremia isolates and used these data to unravel complex mobile genetic element structures mediating β-lactamase gene amplification. By generating complete genomes of 65 carbapenem nonsusceptible Enterobacterales (CNSE) covering a genetically diverse array of isolates, our findings both generate novel insights into how non-CP-CRE overcome carbapenem treatments and provide researchers scaffolds for characterization of their own non-CP-CRE isolates. Improved recognition of mechanisms driving development of non-CP-CRE could assist with design and implementation of future strategies to mitigate the impact of these increasingly recognized AMR pathogens.

[Clinical and StAR genetic characteristics of 33 children with congenital lipoid adrenal hyperplasia]

Objective: To analyze the clinical and genetic characteristics of 33 children with congenital lipoid adrenal hyperplasia (CLAH) caused by StAR gene defects. Methods: The clinical, biochemical, genetic, and follow-up (until December 2021) data of 33 children diagnosed with CLAH from 2006 to 2021 were retrospectively analyzed in Xinhua Hospital, Shanghai Jiao Tong University School of Medicine. Results: Of the 33 children with CLAH, 17 had a karyotype of 46, XX and 16 had a karyotype of 46, XY; 31 were female and 2 were male by social gender. Classic type and non-classic type were found in 30 and 3 children respectively. The age at diagnosis was 9.0 (3.0, 34.5) months. All the 30 cases with classic CLAH presented within the first year of life with skin hyperpigmentation (28 cases, 93%), vomiting and(or) diarrhea (19 cases, 63%), no increase in body weight (8 cases, 27%), elevated adrenocorticotropic hormone levels (21cases (70%)>275 pmol/L), decreased cortisol levels (47 (31,126) nmol/L), hyponatremia ((126±13) mmol/L), hyperkalemia ((5.7±1.1) mmol/L), and normal 17α-hydroxyprogesterone levels (30 cases, 100%). All these with classic CLAH exhibited female external genitalia. Three children with non-classic CLAH (including 2 cases of 46, XY and 1 case of 46, XX) also showed signs and symptoms of adrenal insufficiency, but 2 of them had an age of onset later than 1 year of age, including 1 case of 46, XY with male external genitalia and 1 case of 46, XX with female external genitalia. The other 46, XY patient with non-classic CLAH presented with adrenal insufficiency at 2 months of age, showing micropenis and hypospadias. In the 17 females with 46, XX, 4 older than 10 years of age showed spontaneous pubertal development. A total of 25 StAR gene pathogenic variants were identified in 33 patients, with p.Q258* (18/66, 27%), p.K236Tfs*47 (8/66, 12%) and p.Q77* (6/66, 9%) being the common variantion. Six novel variants were found, including c.358T>G, c.713_714del, c.125del, c.745-1G>A, c.179-2A>C, and exon 1 deletion. Conclusions: Patients with classic CLAH typically present with signs and symptoms of primary adrenal insufficiency in the early infancy period and female external genitalia. p.Q258*, p.K236Tfs*47 and p.Q77* are common variants in CLAH patients.

Distinguishing responses of acetoclastic and hydrogenotrophic methanogens to ammonia stress in mesophilic mixed cultures

A shift from the acetoclastic to the hydrogenotrophic pathway in methanogenesis under ammonia inhibition is a common observation in anaerobic digestion. However, there are still considerable knowledge gaps concerning the differential ammonia tolerance of acetoclastic and hydrogenotrophic methanogens (AMs and HMs), their responses to different ammonia species (NH₄⁺, NH₃), and their recoverability after ammonia inhibition. With the successful enrichment of mesophilic AMs and HMs cultures, this study aimed at addressing the above knowledge gaps through batch inhibition/recovery tests and kinetic modeling under varying total ammonia (TAN, 0.2-10 g N/L) and pH (7.0-8.5) conditions. The results showed that the tolerance level of HMs to free ammonia (FAN, IC₅₀=1345 mg N/L) and NH₄⁺ (IC₅₀=6050 mg N/L) was nearly 11 times and 3 times those of AMs (NH₃, IC₅₀=123 mg N/L; NH₄⁺, IC₅₀=2133 mg N/L), respectively. Consistent with general belief, the AMs were more impacted by FAN. However, the HMs were more adversely affected by NH₄⁺ when the pH was ≤8.0. A low TAN (1.0-4.0 g N/L) could cause irreversible inhibition of the AMs due to significant cell death, whereas the activity of HMs could be fully or even over recovered from severe ammonia stress (FAN≤ 0.9 g N/L or TAN≤10 g N/L; pH ≤8.0). The different tolerance responses of AMs and HMs might be associated with the cell morphology, multiple energy-converting systems, and Gibbs free energy from substrate-level phosphorylation.

FexN produced in pharmaceutical sludge biochar by endogenous Fe and exogenous N doping to enhance peroxymonosulfate activation for levofloxacin degradation

For preparing high performance biochar to be applicated in persulfate-based oxidation treatment of wastewater, the feasibility of deriving Fe-N biochar from pharmaceutical sludge by endogenous Fe and exogenous N doping was investigated. With exogenous urea doping, Fe_xN contained biochar (PZBC800U) was successfully derived from endogenous Fe(OH)₃ contained pharmaceutical sludge. PZBC800U effectively activated peroxymonosulfate (PMS) to remove 80 mg·L^-1 levofloxacin (LEV) within 90 min. The main mechanism of PMS activation by PZBC800U for LEV degradation was revealed as non-radical pathways dominated by ¹O₂ generation and direct electron transfer. The formation of Fe_xN combined with the increase of pyridinic-N in the biochar changed the electronic structure, improved the electron transfer ability, and thus achieved the excellent PMS activation capacity of the biochar. The vital function of endogenous Fe(OH)₃ was verified by comparing PZBC800U to Fe leached and extra Fe added controls. A total of 18 intermediates in the degradation of LEV were identified, and degradation pathways were proposed. Combined with the average local ionization energy calculation, the priority of piperazine breakage during LEV degradation was experimentally proved and mechanistically elucidated. This study provides a new insight into Fe_xN biochar preparation from pharmaceutical sludge and the mechanisms of its excellent PMS activation performance for LEV degradation.

Low energy harvesting of hydrophobic microalgae (Tribonema sp.) by electro-flotation without coagulation

Microalgae have great potential for biofuel production and wastewater treatment, but the high cost of harvesting hinders their practical application. In this study, economical harvesting of hydrophobic microalgae by electro-flotation without coagulation was assessed. The harvesting performance of this method for selected species of freshwater microalgae with different degrees of hydrophobicity (Tribonema sp., highly hydrophobic; Scenedesmus sp., moderately hydrophobic; and Pandorina sp., hydrophilic) were compared. It was found that microalgal hydrophobicity played a critical role in electro-flotation. Under the same condition (current 0.3 A, velocity gradient 200 s^-1, biomass concentration 1 g/L), Tribonema sp. could be effectively harvested (96.2 ± 0.4%) after 20 min of electro-flotation, while the harvesting efficiency decreased significantly with Scenedesmus sp. (70.1 ± 5.2%, 20 min) and Pandorina sp. (<10%, 1 h). The influences of current, electrolysis time, mixing intensity (velocity gradient) and biomass concentration on Tribonema sp. (hydrophobic) harvesting were further investigated. Increasing the current within a certain range (0.1 A-0.4 A) was beneficial to harvesting, while it's further increase decreased floating velocity, which was similar to the effect of the velocity gradient. Under the optimal condition, the harvesting efficiency of Tribonema sp. was 96.3% and the energy consumption (0.19 kWh/kg biomass) was much lower than other harvesting techniques, indicating that electro-flotation is a time-saving and economical approach for hydrophobic microalgae harvesting.

[Disease spectrum analysis of children with inherited metabolic diseases detected by gas chromatography-mass spectrometry of urinary organic acids]

Objective: To investigate the spectrum of amino acid, organic acid, and fatty acid oxidative metabolic diseases in children diagnosed by detecting urinary organic acid levels using gas chromatography-mass spectrometry. Methods: From January 2005 to December 2021, clinical data of 2 461 children diagnosed with inherited metabolic diseases (IMD) by gas chromatography-mass spectrometry, in combination with tandem mass spectrometry and genetic testing in Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine were retrospectively analyzed. Results: Among 2 461 children, 1 446 were male and 1 051 were female. A total of 32 types of IMD were detected among 2 461 patients, which included 10 amino acid disorders in 662 cases (26.9%), 6 common diseases were hyperphenylalaninemia, citrin deficiency, ornithine carbamoyltransferase deficiency, maple syrup urine disease, alkaptonuria, and tyrosinemia-I, 17 types of organic acidemias in 1 683 cases (68.4%), 6 common diseases were methylmalonic acidemia, propionic acidemia, valeric acidemia-type Ⅰ, isovaleric acidemia, 3-methylcrotonyl-CoA carboxylase deficiency and multiple carboxylase deficiency and 5 fatty acid β oxidative defects in 116 cases (4.7%), 2 common diseases were multiple acyl-CoA dehydrogenase deficiency and short-chain acyl-CoA dehydrogenase deficiency). Conclusion: Among the diseases diagnosed by analyzing urinary organic acid profiling with gas chromatography-mass spectrometry, the most common are organic acidemias, followed by amino acid disorders and fatty acid oxidation defects.

Stimulatory effects of biochar addition on dry anaerobic co-digestion of pig manure and food waste under mesophilic conditions

The stimulatory effect of biochar addition on dry anaerobic digestion (AD) has been rarely investigated. In this study, the effects of commonly used biochars (bamboo, rice husk, and pecan shell) on dry co-AD were investigated using mesophilic batch digesters fed with pig manure and food waste as substrates. The results show that the specific methane yield was mildly elevated with the addition of biochars by 7.9%, 9.4%, and 12.0% for bamboo, rice husk, and pecan shell-derived biochar additions, respectively. Biochar did facilitate the degradation of poorly biodegradable organics. In comparison, there was no significant effect on the peak methane production rate by the supplementation of the selected biochars. Among the three mechanisms of enhancing methanogenesis by biochar (buffering, providing supporting surface, and enhancing electron transfer), the first two mechanisms did not function significantly in dry co-AD, while the third mechanism (i.e., enhancing electron transfer) might play an important part in dry AD process. It is recommended that the utilization of biochar for the enhancement of biomethanation in dry AD should be more focused on mono digestion in future studies.

Photodegradation of roxarsone in the aquatic environment: influencing factors, mechanisms, and artificial neural network modeling

Roxarsone (ROX), an organoarsenic feed additive, can be discharged into aquatic environment and photodegraded into more toxic inorganic arsenics. However, the photodegradation behavior of ROX in aquatic environment is still unclear. To better understand ROX photodegradation behavior, the influencing factors, photodegradation mechanism, and process modelling of ROX photodegradation were investigated in this study. The results showed that ROX in the aquatic environment was degraded to inorganic As(III) and As(V) under light irradiation. The degradation efficiency was enhanced by 25% with the increase of light intensity from 300 to 800 μW/cm² via indirect photolysis. The photodegradation was temperature dependence, but was only slightly affected by pH. Nitrate ion (NO₃^-) had an obvious influence, but sulfate, carbonate, and chlorate ions had a negligible effect on ROX degradation. Dissolved organic matter (DOM) in the solution inhibited the photodegradation. ROX photodegradation was mainly mediated by reactive oxygen species (in the form of single oxygen ¹O₂) generated through ROX self-sensitization under irradiation. Based on the data of factors affecting ROX photodegradation, ROX photodegradation model was built and trained by an artificial neural network (ANN), and the predicted degradation rate was in good agreement with the real values with a root mean square error of 1.008. This study improved the understanding of ROX photodegradation behavior and provided a basis for controlling the pollution from ROX photodegradation.

[HBx promotes ubiquitination and degradation of ZO1 and increases the migration and invasion of liver cancer cells]

Objective: To study the effect of hepatitis B virus X protein (HBx) expression level on migration and invasion of zonula occludens protein-1 (ZO-1) in HepG2 liver cancer cells. Methods: Liver cancer cells were transfected with HBV full gene plasmid (pcDNA3.1-HBV1. 1 or pcDNA3.1-HBV1.3), empty plasmid (pcDNA3.1) and HBV-encoded protein plasmids (pHBc, pHBs, pHBp and pHBx), respectively. Western blot and RT-PCR were used to detect ZO1 protein and mRNA levels. Immunoprecipitation was used to detect transfected pHBx. Western blot was used to detect ZO1 ubiquitination levels. Transwell chambers were used to assess cell migration and invasion. Cell proliferation and lactate dehydrogenase assay was used to detect siRNA transfecting targeting ZO1. Flow cytometry was used to detect cell apoptosis and cycle. The data was compared between two and multiple groups by using an independent sample t-test and one-way analysis of variance. Results: Compared with the empty plasmid, ZO1 protein level in HepG2 cells after transiently transfected with pHBV1.1 and pHBV1.3 was decreased by 42.99% ± 6.8% and 55.0% 5 ± 4.56%, respectively, and their mRNA levels did not change significantly. ZO1 protein level in Huh7 cells was decreased by 17.46% ± 4.94% and 47.53% ± 3.38%, respectively. ZO1 protein level after transfection with pHBx was decreased by 47.02% ± 3.4%, while the ZO1 protein level after transfection with pHBc, pHBs and pHBp did not change significantly. ZO1 mRNA level was unaffected with pHBx transfection. ZO1 ubiquitin level and cell migration and invasion ability in HepG2 cells was significantly increased with transfected pHBx. HepG2 cells proliferation, apoptosis and cycle after transfection with ZO1-targeted siRNA did not change significantly, but the migration and invasion ability were significantly increased. Conclusion: HBx can increase the migration and invasion of liver cancer cells by promoting the ubiquitination and degradation of ZO1 protein level.

[Analysis of six children with 3-methylglutaconic aciduria]

Objective: To explore the clinical characteristics, genotypes and long-term outcomes of individuals with 3-methylglutaconic aciduria. Methods: The clinical features, biochemical data, genetic test results and treatment outcomes of six children with 3-methylglutaconic aciduria admitted to the Department of Endocrinology, Genetics and Metabolism, Xinhua Hospital from February 2017 to February 2019 were retrospectively analyzed and the Gesell developmental diagnosis schedule was performed to evaluate the development of four patients. Results: Among 6 children with 3-methylglutaconic aciduria 2 were males and 4 were females.Four cases had 3-methylglutaconic aciduria type Ⅰ and 2 cases had 3-methylglutaconic aciduria with deafness,encephalopathy, and Leigh-like syndrome. Five of 6 patients were detected by newborn screening among whom 4 remained asymptomatic, and only one had a postmortem diagnosis. Among them, 4 patients remained asymptomatic, while two presented with clinical symptoms such as jaundice and dyspnea and the age of disease onset was 1 and 2 days respectively. The concentration of 3-methylglutaconic acid in urine of all affected individuals was between 22.38 and 77.09 mmol/molCr, which was above the normal value. Genetic tests were performed for all patients. Eleven variants were identified in 2 genes, of which 10 variants were novel and only c.442C>T p.(R148X) has been previously reported; Seven variants (c.656-2delA, EX5-EX6 Del, c.942+3A>G, c.373C>T p.(R125W), c.895-3C>G, c.667C>T p.(R223X) and c.894+5G>A) were in AUH gene. The others (c.548G>A p.(R138Q), c.442C>T p.(R148X), c.1339C>T p.(R447X) and c.973dupA p.(M325Nfs*5) were in SERAC1 gene. After being treated with leucine diet restriction and L-carnitine, 4 patients with AUH gene variation who were from asymptomatic phase developed normally, whereas those 2 patients with SERAC1 gene variation had a poor prognosis. During the follow-up, 2 patients exhibited varying degrees of psychomotor retardation, the rest had normal course of development. Conclusions: There are significant clinical heterogeneities among individuals with 3-methylglutaconic aciduria. The most common pathogenic variants are splicing variations, followed by nonsense, missense and frameshift mutations. Leucine-free diet and oral L-carnitine therapy are effective for some patients. Newborn screening is essential for early diagnosis and improvement of prognosis.

Enrichment of Autotrophic Denitrifiers From Anaerobic Sludge Using Sulfurous Electron Donors

This study compared the rates and microbial community development in batch bioassays on autotrophic denitrification using elemental sulfur (S0), pyrite (FeS2), thiosulfate (S2O3 2-), and sulfide (S2-) as electron donor. The performance of two inocula was compared: digested sludge (DS) from a wastewater treatment plant of a dairy industry and anaerobic granular sludge (GS) from a UASB reactor treating dairy wastewater. All electron donors supported the development of a microbial community with predominance of autotrophic denitrifiers during the enrichments, except for sulfide. For the first time, pyrite revealed to be a suitable substrate for the growth of autotrophic denitrifiers developing a microbial community with predominance of the genera Thiobacillus, Thioprofundum, and Ignavibacterium. Thiosulfate gave the highest denitrification rates removing 10.94 mM NO3 - day-1 and 8.98 mM NO3 - day-1 by DS and GS, respectively. This was 1.5 and 6 times faster than elemental sulfur and pyrite, respectively. Despite the highest denitrification rates observed in thiosulfate-fed enrichments, an evaluation of the most relevant parameters for a technological application revealed elemental sulfur as the best electron donor for autotrophic denitrification with a total cost of 0.38 € per m3 of wastewater treated.

[Effects of pressure steam sterilization times on the accuracy of the digital intraoral scanning data]

Objective: To provide a scientific basis for the standardized operation of clinical disinfection by comparing and analyzing the influence of disinfection times on the accuracy of digital intraoral scanning. Methods: The author prepared 10 brand-new intraoral scanning heads (Trios, 3Shape, Denmark), scan the same plaster standard dentition model after 1, 20, 40, and 60 times of pressure steam sterilization, and obtained the data of four groups of experimental groups A, B, C, D, and scan the model 5 times repeatedly after each disinfection cycle of each scanning head. A model scanner (D2000, 3Shape, Denmark) was used to scan the standard dentition model, and the scan results were used as the control group data. Vernier calipers and measurement software were used to measure the arch length (the distance between the mesial cheek tips of the first molars on both sides of the maxillary) and the front and back length (the distance from the tongue protrusion of the right incisor to the buccal tip of the first molar on the right of the upper jaw) of the plaster model and the data of the 4 experimental groups. The line distance results of the 4 groups of experimental groups were compared for statistical analysis, and the trueness and precision values of the 4 groups of experimental groups were compared for statistical analysis. Results: The length of the arch across the 4 experimental groups increased with the increase in the number of disinfection (P<0.05), and there were statistical differences compared with the measurement results of the plaster model (P<0.05); the differences in the length of the dental arch were not statistically significant (P>0.05). The treness of the 4 experimental groups is statistically significant (P<0.05), and the trueness was from high to low in order of group A [(114.85±3.75) μm], group B [(124.65±3.85) μm], group C [(131.45±3.04) μm] and group D [(144.64±3.34) μm]; the precision of the 4 experimental groups was not statistically significant (P>0.05). Conclusions: The number of times of pressure steam sterilization can affect the accuracy of the scanning results of the digital intraoral scanner, and with the increase of the number of sterilizations, the error of the scanning results also tends to increase. The number of sterilizations has no effect on the repeatability of the digital scanning results. The increase in the number of times of pressure steam sterilization affects the accross of the arch but has no effect on the length of the dental arch, and the range of change of the length of the arch is within the clinically acceptable range. After 60 times of pressure steam sterilization, the accuracy of digital scan data can still meet clinical needs.

Fermentation liquid production of food wastes as carbon source for denitrification: Laboratory and full-scale investigation

Nitrogen removal is often limited in municipal wastewater treatment due to the insufficiency of carbon source, and using food wastes fermentation liquid as carbon source could cut down the cost of operating and recycle food wastes. Food wastes fermentation liquid production and application as external carbon source were explored in the laboratory and full-scale system in this study. In the laboratory scale, lactic acid and VFAs were the main components of fermentation liquid, and the highest total chemical oxygen demand (TCOD) production was obtained with activated sludge as inoculum. The yield of TCOD was around 794.5 mg/g TS_fed and NH₄⁺-N was 3.5 mg/g TS_fed. The denitrification rate with fermentation liquid was slightly lower than acetic acid and butyric acid, but higher than lactic acid and starch. In the full-scale investigation, the TCOD concentration in fermentation liquid was in the range of 6.9-12.8 g/L and the ratio of TCOD/inorganic nitrogen was 210.5-504.5:1. NO₃^--N removal increased from 52.1% to 94.2% after fermentation liquid addition, confirming the potentiality of food wastes fermentation liquid replace the commercial carbon source in wastewater treatment plants.

Improved reduction of antibiotic resistance genes and mobile genetic elements from biowastes in dry anaerobic co-digestion

This study investigated the performance of anaerobic co-digestion (AcoD) of pig manure and food waste on the reduction of antibiotic resistomes under wet and dry AcoD conditions. High-throughput quantitative PCR technology was utilized for a comprehensive assessment of the performances of the two processes. The results show that dry AcoD with a total solids (TS) content of 20% effectively reduced total antibiotic resistance genes (ARGs) by 1.24 log copies/g wet sample, while only 0.54 log copies/g wet sample was reduced in wet AcoD with a TS content of 5%. Dry AcoD was more efficient in reduction of aminoglycosides, multidrug and sulfonamide resistance genes compared with the reduction of other classes of ARGs. Dry AcoD caused a significant reduction of ARGs with resistance mechanisms of efflux pump and antibiotic deactivation. In contrast, there was no obvious difference in reductions of ARGs with different resistance mechanisms in wet AcoD. Network analysis showed that ARGs were significantly correlated with mobile genetic elements (MGEs) (Spearman's r > 0.8, P < 0.05), as well as microbial communities. Enrichment of ARGs and MGEs was found at the early period of AcoD processes, indicating some ARGs and MGEs increased during the hydrolysis and acidogenesis stages. But after a long retention time, their abundances were effectively reduced by dry AcoD in the subsequent stages.

Organoarsenic feed additives in biological wastewater treatment processes: Removal, biotransformation, and associated impacts

Aromatic organoarsenicals are widely used in animal feeding operations and cause arsenic contamination on livestock wastewater and manure, thereby raising the risk of surface water pollution. Biological wastewater treatment processes are often used for livestock wastewater treatment. Organoarsenic removal and biotransformation under aerobic and anaerobic conditions, and the associated impacts have received extensive attention due to the potential threat to water security. The removal efficiency and biotransformation of organoarsenicals in biological treatment processes are reviewed. The underlying mechanisms are discussed in terms of functional microorganisms and genes. The impacts associated with organoarsenicals and their degradation products on microbial activity and performance of bioreactors are also documented. Based on the current research advancement, knowledge gaps and potential research in this field are discussed. Overall, this work delivers a comprehensive understanding on organoarsenic behaviors in biological wastewater treatment processes, and provides valuable information on the control of arsenic contamination from the degradation of organoarsenicals in biological wastewater treatment processes.

A review on control of harmful algal blooms by plant-derived allelochemicals

Harmful algal blooms (HABs) have several negative impacts on aquatic ecosystem, and even harm to humans. Utilization of allelochemicals to inhibit microalgal overgrowth is an environment-friendly approach for controlling HABs. This paper demonstrated the development of allelochemicals with algicidal effects, including the development history of allelopathy, the application methods, the reported allelopathic plants and their derived allelochemicals. Allelopathy is a promising strategy to control HABs as the effectiveness of allelochemicals on inhibiting microalgae cells has been discovered and confirmed for many years. The proposed allelopathic mechanisms and species-selective properties were expounded as well. Moreover, this paper further proposed suggestions for the further research and development of allelopathy strategy for HABs control.

Filamentous microalgae as an advantageous co-substrate for enhanced methane production and digestate dewaterability in anaerobic co-digestion of pig manure

This study aimed at exploring filamentous microalgae (Tribonema sp.) as an advantageous co-substrate for anaerobic digestion (AD) of pig manure. Its impacts on the AD performance were assessed in terms of methane yield, energy conversion efficiency, digestion kinetics, and digestate dewaterability. The microalgae substantially improved methane yield, AD kinetics, and digestate dewaterability of the AD process. The enhancement in methane yield ranged from 2 to 27.4%, with the maximum enhancement (corresponding to an energy conversion efficiency of 81%) occurring at a mixing ratio of 1:1 (VS basis). The AD kinetics was improved as indicated by the increased hydrolysis rate constants and diminished lag time. The specific resistance to filtration (SRF) of the digestate decreased significantly with the increasing proportion of the microalgae in the co-substrates, which would facilitate digestate processing and valorisation. Subsequently, the high biomass productivity of the microalgae (441 mg/L/d) in liquid digestate would enable sustainable bioenergy production through nutrient recycling.

Anaerobic biotransformation of roxarsone regulated by sulfate: Degradation, arsenic accumulation and volatilization

Roxarsone, an extensively used organoarsenical feed additive, is often pooled in livestock wastewater. Sulfate exists ubiquitously in livestock wastewater and is capable for arsenic remediation. However, little is known about impacts of sulfate on roxarsone biotransformation during anaerobic digestion of livestock wastewater. In this study, the biodegradation of 5.0 mg L^-1 roxarsone, and the accumulation and volatilization of the generated arsenical metabolites in a sulfate-spiked upflow anaerobic granular blanket reactor were investigated. Based on the analysis of degradation products, the nitro and arsenate groups of roxarsone were successively reduced to amino and arsenite groups before the C-As bond cleavage. Effluent arsenic concentration was ∼0.75 mg L^-1, of which 82.9-98.5% were organoarsenicals. The maximum arsenic volatilization rate reached 32.6 μg-As kg^-1-VS d^-1. Adding 5.0 mg L^-1 sulfate enabled 66.7% and 45.9% decrease in inorganic arsenic concentration and arsenic volatilization rate, respectively. Arsenic content in the anaerobic granular sludge (AGS) was accumulated to 1250 mg kg^-1 within 420 days. Based on the results of FESEM-EDS and XPS, sulfate addition induced arsenic precipitation in the AGS through the formation of orpiment. Arsenic in the effluent, biogas and AGS accounted for 52.9%, 0.01% and 47.1% of the influent arsenic when the reactor operated stably. The findings from this study suggest that sulfate has effectively regulatory effects on arsenic immobilization and volatilization during anaerobic digestion of organoarsenic-contaminated livestock wastewater.

A novel technology with precise oxygen-input control: Application of the partial nitritation-anammox process

Reliable and accurate oxygen-input control, which is critical to maintaining efficient nitrogen removal performance for partial nitritation-anammox (PN-A) process, remains one of the main operational difficulties. In this study, a novel, yet simple system (a simple process for autotrophic nitrogen-removal, SPAN) with precise oxygen-input control was developed to treat ammonium-rich wastewater via PN-A process. SPAN brings oxygen to biomass by circulating water and creating water spray (shower) at the water-air interface, and effectively balances the activities of core functional microorganisms through precise oxygen-input control. The oxygen-input rate is decided by the water circulation rate and shower rate and is measurable and predictable. Therefore, the required amount of oxygen for ammonium oxidation can be precisely delivered to the biomass by adjusting the circulation rate and shower rate. The results of two parallel SPAN reactors demonstrated that during long-term operation, the required oxygen input was precisely and reliably controlled. More than 99% of NH₄⁺-N and 81% - 85% of total nitrogen were stably removed, with anammox bacteria contributing to more than 96% of total nitrogen removal. Anammox bacteria were efficiently enriched to the highest level among the key nitrogen-converting microbial groups, both in terms of abundance (8.17%) and nitrogen-conversion capacity, while ammonium oxidizing bacteria were well controlled to provide sufficient ammonium-oxidizing capacity. Nitrite oxidizing bacteria were maintained stable (relative abundance of 1.08%-1.88%) and their activity was effectively suppressed. This study provided a novel technology, SPAN, to precisely control oxygen input in PN-A system, and proved that SPAN was effective and reliable in achieving long-term high-efficiency nitrogen removal.

[Postinflammatroy pulmonary fibrosis of COVID-19: the current status and perspective]

The novel coronavirus pneumonia (COVID-19) has been well controlled in China. Most of the COVID-19 patients were having postinflammatory pulmonary fibrosis (PPF) on the follow-up CT scan when discharged, and complaining about exertional dyspnea of different levels, presenting with an UIP (usual interstitial pneumonia) pattern or NSIP (non-specific interstitial pneumonia) pattern on the CT scans. Will the PPF get improved or stay stable, or progress? Such questions could only be answered by follow-up and monitoring of the pulmonary function. At the same time, we should learn from the lessons on pulmonary function loss of the SARS patients and MERS patients, some of whom had persistent impaired lung function after discharge. Pirfenidone and Nintedanib had been approved for the treatment of idiopathic pulmonary fibrosis(IPF), showing effectiveness on non-IPF pulmonary fibrosis as well. However, there are no studies about the application on PPF resulting from viral pneumonia. Given the follow-up status of SARS patients and MERS patients, and the PPF of COVID-19 patients, we should be careful about the discharged patients with a close follow-up, and further studies on PPF of COVID-19 are needed.

Impact of total solids content on anaerobic co-digestion of pig manure and food waste: Insights into shifting of the methanogenic pathway

Dry anaerobic digestion (AD) has advantages over wet AD in treating high-solid organic wastes like livestock and food wastes, but an elevated total solids (TS) content would affect the AD performances. In this study, methane production of digesters co-digesting pig manure (PM) and food waste (FW) at different TS contents (R₁, TS 5%; R₂, TS 10%; R₃, TS 15%; and R₄, TS 20%) was assessed. The results showed the specific methane yield had no significant difference with the increase of TS contents from 5% to 15% (278.8-291.7 NmL/g VS_added), while it was reduced at a 20% TS content (259.8 NmL/g VS_added). Two peaks of total volatile fatty acids and daily methane production were observed in the high-solid digesters (R₂-R₄), while only one peak occurred in wet AD (R₁). A new kinetics model was developed to describe the two-peak methane production behavior at high TS contents. The analysis on the microbial community structure clearly showed the different evolutions of methanogenic pathways in low and high solids content systems. In dry AD (R₄), there was a general shifting from the acetoclastic pathway, to mixotrophic pathway and hydrogenotrophic pathway, with the dominance of mixotrophic and hydrogenotrophic methanogens.

Iron sulphides mediated autotrophic denitrification: An emerging bioprocess for nitrate pollution mitigation and sustainable wastewater treatment

Iron sulphides, mainly in the form of mackinawite (FeS), pyrrhotite (Fe_1-xS, x = 0-0.125) and pyrite (FeS₂), are the most abundant sulphide minerals and can be oxidized under anoxic and circumneutral pH conditions by chemoautotrophic denitrifying bacteria to reduce nitrate to N₂. Iron sulphides mediated autotrophic denitrification (ISAD) represents an important natural attenuation process of nitrate pollution and plays a pivotal role in linking nitrogen, sulphur and iron cycles in a variety of anoxic environments. Recently, it has emerged as a promising bioprocess for nutrient removal from various organic-deficient water and wastewater, due to its specific advantages including high denitrification capacity, simultaneous nitrogen and phosphorus removal, self-buffering properties, and fewer by-products generation (sulphate, waste sludge, N₂O, NH₄⁺, etc.). This paper provides a critical overview of fundamental and engineering aspects of ISAD, including the theoretical knowledge (biochemistry, and microbial diversity), its natural occurrence and engineering applications. Its potential and limitations are elucidated by summarizing the key influencing factors including availability of iron sulphides, low denitrification rates, sulphate emission and leaching heavy metals. This review also put forward two key questions in the mechanism of anoxic iron sulphides oxidation, i.e. dissolution of iron sulphides and direct substrates for denitrifiers. Finally, its prospects for future sustainable wastewater treatment are highlighted. An iron sulphides-based biotechnology towards next-generation wastewater treatment (NEO-GREEN) is proposed, which can potentially harness bioenergy in wastewater, incorporate resources (P and Fe) recovery, achieve simultaneous nutrient and emerging contaminants removal, and minimize waste sludge production.

Arsenic volatilization in roxarsone-loaded digester: Insight into the main factors and arsM genes

The extensive use of roxarsone (ROX) in livestock and poultry husbandry causes the production of arylarsenic-contaminated manure/wastewater. Anaerobic digestion is a conventional technique for livestock manure/wastewater treatment. However, the factors affecting arsenic volatilization are poorly understood in arylarsenic-loaded anaerobic reactors. The main factors such as ROX loading, exposure time of anaerobic granular sludge (AGS) to ROX, and volatile fatty acid (VFA) levels, affecting arsenic volatilization were investigated in this study. The results indicated that ROX loading of 5.70 mg-As·L^-1 triggered the maximum volatile arsenic yield of 6.78 ng-As·g^-1-VSS·d^-1, which was 4.95 times higher compared to the ROX-free assay. The conversion of ROX into inorganic arsenic was an essential step for arsenic volatilization. The 160-day and 270-day exposure of AGS to ROX caused 6-fold and 8-fold increase in volatile arsenic yield, respectively, compared to the 0-day exposure. With the longer-time exposure to ROX, AGS provided more available arsenic for volatilization and its arsenic-volatilizing capacity was significantly enhanced. VFA level was positively associated with arsenic volatilization (r = 0.832-0.950; p < 0.05). The abundance of arsM genes in AGS increased by 34.62-129.05% after the 100-day incubation, and was strongly correlated to arsenic volatilization. Based on these results, possible pathway of arsenic volatilization in ROX-loaded digesters were proposed. The result from this study improves a better understanding of the potential of arsenic volatilization in arylarsenic-contaminated environments.

[Pharmacotherapeutics for the new coronavirus pneumonia]

The new coronavirus pneumonia (NCP), also named as COVID-19 by WHO on Feb 11 2020, is now causing a severe public health emergency in China since. The number of diagnosed cases is more than 40,000 until the submission of this manuscript. Coronavirus has caused several epidemic situations world widely, but the present contagious disease caused by 2019 new coronavirus is unprecedentedly fulminating. The published cohorts of 2019 new coronavirus (n-Cov) are single-center studies, or retrospective studies. We here share the therapeutic experiences of NCP treatment with literature review. Combination of Ribavirin and interferon-α is recommended by the 5(th) edition National Health Commission's Regimen (Revised Edition) because of the effect on Middle East respiratory syndrome (MERS), and the effectiveness of Lopinavir/Ritonavir and Remdisivir needs to be confirmed by randomized controlled trial (RCT), given the situation of no specific antivirus drug on NCP is unavailable. Systemic glucocorticosteroid is recommended as a short term use (1~2 mg·kg(-1)·d(-1), 3~5 d) by the 5(th) edition National Health Commission's Regimen (Revised Edition) yet RCTs are expected to confirm the effectiveness. Inappropriate application of antibiotics should be avoided, especially the combination of broad-spectrum antibiotics, for the NCP is not often complicated with bacterial infection.

[Pharmacotherapeutics for the New Coronavirus Pneumonia]

The New Coronavirus Pneumonia (NCP, also named as COVID-19 by WHO on Feb 11 2020, is now causing a severe public health emergency in China since. The number of diagnosed cases is more than 40,000 until the submission of this manuscript. Coronavirus has caused several epidemic situations world widely, but the present contagious disease caused by 2019 new Coronavirus is unprecedentedly fulminating. The published cohorts of 2019 new Coronavirus (n-Cov) are single-center studies, or retrospective studies. We here share the therapeutic experiences of NCP treatment with literature review. Combination of Ribavirin and Interferon-α is recommended by the 5(th) edition National Health Commission's Regimen (Revised Edition) because of the effect on MERS (Middle East Respiratory Syndrome), and the effectiveness of Lopinavir/Ritonavir and Remdisivir needs to be confirmed by randomized controlled trial (RCT), given the situation of no specific antivirus drug on NCP is unavailable. Systemic glucocorticosteroid is recommended as a short term use (1~2 mg.kg(-1).d(-1), 3~5d ) by the 5(th) edition National Health Commission's Regimen (Revised Edition) yet RCTs are expected to confirm the effectiveness. Inappropriate application of antibiotics should be avoided, especially the combination of broad-spectrum antibiotics, for the NCP is not often complicated with bacterial infection.

Nutrient removal through pyrrhotite autotrophic denitrification: Implications for eutrophication control

This study investigated nutrient removal kinetics and main influencing factors of natural pyrrhotite autotrophic denitrification (PAD), and nutrient removal performance and the microbial community in the PAD biofilter (PADB). Results demonstrated that both NO₃^- and PO₄^3- in wastewater were nearly completely removed, and biological N removal and chemical P removal took place simultaneously in the PAD process. NO₃^- removal kinetics of the PAD can be described with half-order kinetics. The PAD was effective across a wide temperature range of 11-34 °C, initial NO₃^--N range of 13-52 mg·L^-1 and PO₄^3--P below 60 mg·L^-1. Both NO₃^- and PO₄^3- decreased gradually with wastewater flowing along the PADB. The PADB operation results show that at 12 h HRT, when the PADB treated wastewater containing 30.95 ± 0.97 mg·L^-1 of NO₃^- and 3.02 ± 0.10 mg·L^-1 of PO₄^3--P, the effluent contained 1.15 ± 2.08 and 0.09 ± 0.11 mg·L^-1 of NO₃^--N and PO₄^3--P on average, respectively. In the PADB the dominant bacteria were Thiobacillus and Sulfurimonas, which used pyrrhotite as the electron donor to reduce NO₃^-. The relative abundance of Thiobacillus at the bottom of the PADB increased from 0.81% to 58.65% and that of Sulfurimonas decreased from 97.22% to 12.30%, with exposure to pyrrhotite. From the bottom to the top of the PADB, the relative abundance of Thiobacillus increased from 58.65% to 86.23% and Sulfurimonas decreased from 12.30% to 0.52%. Technologies based on the PAD are promising ways to control eutrophication.