An indirect estimation of x-ray spectrum via convolutional neural network and transmission measurement.

OBJECTIVE: In this work, we aim to propose an accurate and robust spectrum estimation method by synergistically combining X-ray imaging physics with a convolutional neural network (CNN). Approach: The approach relies on transmission measurements, and the estimated spectrum is formulated as a convolutional summation of a few model spectra generated using Monte Carlo simulation. The difference between the actual and estimated projections is utilized as the loss function to train the network. We contrasted this approach with the weighted sums of model spectra approach previously proposed. Comprehensive studies were performed to demonstrate the robustness and accuracy of the proposed approach in various scenarios. Main results: The results show the desirable accuracy of the CNN-based method for spectrum estimation. The ME and NRMSE were -0.021 keV and 3.04% for 80kVp, and 0.006 keV and 4.44% for 100kVp, superior to the previous approach. The robustness test and experimental study also demonstrated superior performances. The CNN-based approach yielded remarkably consistent results in phantoms with various material combinations, and the CNN-based approach was robust concerning spectrum generators and calibration phantoms. Significance: We proposed a method for estimating the real spectrum by integrating a deep learning model with real imaging physics. The results demonstrated that this method was accurate and robust in estimating the spectrum, and it is potentially helpful for broad X-ray imaging tasks.

Deciphering the spatial heterogeneity of groundwater arsenic in Quaternary aquifers of the Central Yangtze River Basin.

Significant spatial variability of groundwater arsenic (As) concentrations in South/Southeast Asia is closely associated with sedimentogenesis and biogeochemical cycling processes. However, the role of fine-scale differences in biogeochemical processes under similar sedimentological environments in controlling the spatial heterogeneity of groundwater As concentrations is poorly understood. Within the central Yangtze Basin, dissolved organic matter (DOM) and microbial functional communities in the groundwater and solid-phase As-Fe speciation in Jianghan Plain (JHP) and Jiangbei Plain (JBP) were compared to reveal mechanisms related to the spatial heterogeneity of groundwater As concentration. The optical signatures of DOM showed that low molecular terrestrial fulvic-like with highly humified was predominant in the groundwater of JHP, while terrestrial humic-like and microbial humic-like with high molecular weight were predominant in the groundwater of JBP. The inorganic carbon isotope, microbial functional communities, and solid-phase As-Fe speciation suggest that the primary process controlling As accumulation in JHP groundwater system is the degradation of highly humified OM by methanogens, which drive the reductive dissolution of amorphous iron oxides. While in JBP groundwater systems, anaerobic methane-oxidizing microorganisms (AOM) coupled with fermentative bacteria, iron reduction bacteria (IRB), and sulfate reduction bacteria (SRB) utilize low molecular weight DOM degradation to drive biotic/abiotic reduction of Fe oxides, further facilitating the formation of carbonate associated Fe and crystalline Fe oxides, resulting in As release into groundwater. Different biogeochemical cycling processes determine the evolution of As-enriched aquifer systems, and the coupling of multiple processes involving organic matter transformation­iron cycling­sulfur cycling-methane cycling leads to heterogeneity in the spatial distribution of As concentrations in groundwater. These findings provide new perspectives to decipher the spatial variability of As concentrations in groundwater.

Sulfate-reducing bacteria (SRB) mediated carbonate dissolution and arsenic release: Behavior and mechanisms.

Carbonate bound arsenic act as an important reservoir for arsenic (As) in nature aquifers. Sulfate-reducing bacteria (SRB), one of the dominant bacterial species in reductive groundwater, profoundly affects the biogeochemical cycling of As. However, whether and how SRB act on the migration and transformation of carbonate bound arsenic remains to be elucidated. Batch culture experiment was employed using filed collected arsenic bearing calcite to investigate the release and species transformation of As by SRB. We found that arsenic in the carbonate samples mostly exist as inorganic As(V) (93.92 %) and As(III). The present of SRB significantly facilitated arsenic release from carbonates with a maximum of 22.3 µg/L. The main release mechanisms of As by SRB include 1) calcite dissolution and the liberate of arsenic in calcite lattices, and 2) the break of H-bonds frees arsenic absorbed on carbonate surface. A redistribution of arsenic during culture incubation took place which may due to the precipitation of As2Sx or secondary FeAl minerals. To our best knowledge, it is the first experimental study focusing on the release of carbonate bound arsenic by SRB. This study provides new insights into the fate and transport of arsenic mediated by microorganism within high arsenic groundwater-sediment system.

Effects of MEK1/2 inhibitor U0126 on FGF10-enhanced buffalo oocyte maturation in vitro.

Fibroblast growth factor 10 (FGF10) plays critical roles in oocyte maturation and embryonic development; however, the specific pathway by which FGF10 promotes in vitro maturation of buffalo oocytes remains elusive. The present study was aimed at investigating the mechanism underlying effects of the FGF10-mediated extracellular regulated protein kinases (ERK) pathway on oocyte maturation and embryonic development in vitro. MEK1/2 (mitogen-activated protein kinase kinase) inhibitor U0126, alone or in combination with FGF10, was added to the maturation culture medium during maturation of the cumulus oocyte complex. Morphological observations, orcein staining, apoptosis detection, and quantitative real-time PCR were performed to evaluate oocyte maturation, embryonic development, and gene expression. U0126 affected oocyte maturation and embryonic development in vitro by substantially reducing the nuclear maturation of oocytes and expansion of the cumulus while increasing the apoptosis of cumulus cells. However, it did not have a considerable effect on glucose metabolism. These findings suggest that blocking the MEK/ERK pathway is detrimental to the maturation and embryonic development potential of buffalo oocytes. Overall, FGF10 may regulate the nuclear maturation of oocytes and cumulus cell expansion and apoptosis but not glucose metabolism through the MEK/ERK pathway. Our findings indicate that FGF10 regulates resumption of meiosis and expansion and survival of cumulus cells via MEK/ERK signaling during in vitro maturation of buffalo cumulus oocyte complexes. Elucidation of the mechanism of action of FGF10 and insights into oocyte maturation should advance buffalo breeding. Further studies should examine whether enhancement of MEK/ERK signaling improves embryonic development in buffalo.

Geogenic Phosphorus Enrichment in Groundwater due to Anaerobic Methane Oxidation-Coupled Fe(III) Oxide Reduction.

Accumulation of geogenic phosphorus (P) in groundwater is an emerging environmental concern, which is closely linked to coupled processes involving FeOOH and organic matter under methanogenic conditions. However, it remains unclear how P enrichment is associated with methane cycling, particularly the anaerobic methane oxidation (AMO). This study conducted a comprehensive investigation of carbon isotopes in dissolved inorganic carbon (DIC), CO2, and CH4, alongside Fe isotopes, microbial communities, and functions in quaternary aquifers of the central Yangtze River plain. The study found that P concentrations tended to increase with Fe(II) concentrations, δ56Fe, and δ13C-DIC, suggesting P accumulation due to the reductive dissolution of FeOOH under methanogenic conditions. The positive correlations of pmoA gene abundance versus δ13C-CH4 and Fe concentrations versus δ13C-CH4, and the prevalent presence of Candidatus_Methanoperedens, jointly demonstrated the potential significance of Fe(III)-mediated AMO process (Fe-AMO) alongside traditional methanogenesis. The increase of P concentration with δ13C-CH4 value, pmoA gene abundance, and Fe concentration suggested that the Fe-AMO process facilitated P enrichment in groundwater. Redundancy analysis confirmed this assertion, identifying P concentration as the primary determinant and the cooperative influence of Fe-AMO microorganisms such as Candidatus_Methanoperedens and Geobacter on P enrichment. Our work provided new insights into P dynamics in subsurface environments.

Enrichment of Geogenic Organoiodine Compounds in Alluvial-Lacustrine Aquifers: Molecular Constraints by Organic Matter.

Organoiodine compounds (OICs) are the dominant iodine species in groundwater systems. However, molecular mechanisms underlying the geochemical formation of geogenic OICs-contaminated groundwater remain unclear. Based upon multitarget field monitoring in combination with ultrahigh-resolution molecular characterization of organic components for alluvial-lacustrine aquifers, we identified a total of 939 OICs in groundwater under reducing and circumneutral pH conditions. In comparison to those in water-soluble organic matter (WSOM) in sediments, the OICs in dissolved organic matter (DOM) in groundwater typically contain fewer polycyclic aromatics and polyphenol compounds but more highly unsaturated compounds. Consequently, there were two major sources of geogenic OICs in groundwater: the migration of the OICs from aquifer sediments and abiotic reduction of iodate coupled with DOM iodination under reducing conditions. DOM iodination occurs primarily through the incorporation of reactive iodine that is generated by iodate reduction into highly unsaturated compounds, preferably containing hydrophilic functional groups as binding sites. It leads to elevation of the concentration of the OICs up to 183 µg/L in groundwater. This research provides new insights into the constraints of DOM molecular composition on the mobilization and enrichment of OICs in alluvial-lacustrine aquifers and thus improves our understanding of the genesis of geogenic iodine-contaminated groundwater systems.

[Clinical and genetic analysis of a child with Canavan disease due to compound heterozygous variants of ASPA gene].

OBJECTIVE: To analyze the clinical phenotype and genetic characteristics for a child with Canavan disease. METHODS: A child who was admitted to the Children's Hospital Affiliated to Shandong University on April 9, 2021 for inability to uphold his head for 2 months and increased muscle tone for one week was subjected to whole exome sequencing, and candidate variants were verified by Sanger sequencing. RESULTS: Genetic testing revealed that the child has harbored compound heterozygous variants of the ASPA gene, including a paternally derived c.556_559dupGTTC (p. L187Rfs*5) and a maternally derived c.919delA (p. S307Vfs*24). Based on the guidelines from the American College of Medical Genetics and Genomics, both variants were predicted to be pathogenic (PVS1+PM2_Supporting+PM3). CONCLUSION: The c.556_559dupGTTC (p.L187Rfs*5) and c.919delA (p.S307Vfs*24) compound heterozygous variants of the ASPA gene probably underlay the pathogenesis of Canavan disease in this child.

Unravelling the impacts of soluble Mn(III)-NOM on arsenic immobilization by ferrihydrite or goethite under aquifer conditions.

The environmental fate of arsenic (As) relies substantially on its speciation, which occurs frequently coupled to the redox transformation of manganese. While trivalent manganese (Mn(III)), which is known for its high reactivity, is believed to play a role in As mobilization by iron (oxyhydr)oxides in dynamic aquifers, the exact roles and underlying mechanisms are still poorly understood. Using increasingly complex batch experiments that mimick As-affected aquifer conditions in combination with time-resolved characterization, we demonstrate that Mn(III)-NOM complexes play a crucial role in the manganese-mediated immobilization of As(III) by ferrihydrite and goethite. Under anaerobic condition, Mn(III)-fulvic acid (FA) rapidly oxidized 31.8% of aqueous As(III) and bound both As(III) and As(V). Furthermore, Mn(III)-FA exerted significantly different effects on the adsorption of As by ferrihydrite and goethite. Mn(III)-FA increased the adsorption of As by 6-16% due to the higher affinity of oxidation-produced As(V) for ferrihydrite under circumneutral conditions. In contrast, As adsorption by crystalline goethite was eventually inhibited due to the competitive effect of Mn(III)-FA. To summarize, our results reveal that Mn(III)-NOM complexes play dual roles in As retention by iron oxides, depending on the their crystallization. This highlights the importance of Mn(III) for the fate of As particularly in redox fluctuating groundwater environments.

Heterologous Expression and Characterization of a Novel Mesophilic Maltogenic α-Amylase AmyFlA from Flavobacterium sp. NAU1659.

A novel amylase AmyFlA from Flavobacterium sp. NAU1659, AmyFlA, was cloned and expressed in Esherichia coli. Based on phylogenetic and functional analysis, it was identified as a novel member of the subfamily GH13_46, sharing high sequence identity. The protein was predicted to consist of 620 amino acids, with a putative signal peptide of 25 amino acids. The enzyme was able to hydrolyze soluble starch with a specific activity of 352.97 U/mg at 50 °C in 50 mM phosphate buffer (pH 6.0). The Km and Vmax values of AmyFlA were respectively 3.15 mg/ml and 566.36 µmol·ml-1·min-1 under optimal conditions. Its activity towards starch was enhanced by 63% in the presence of 1 mM Ca2+, indicating that AmyFlA was a Ca2+-dependent amylase. Compared to the reported maltogenic amylases, AmyFlA produced a lower variety of intermediate oligosaccharides at the start of the reaction so that the product mixture contained a higher proportion of maltose. These results indicate that AmyFlA may be potential application value in the production of high-maltose syrup.

Integration of hydrothermal liquefaction of Cyanophyta and supercritical water oxidation of its aqueous phase products: Biocrude production and nutrient removal.

Cyanophyta has the potential to produce biocrude via hydrothermal liquefaction (HTL). However, aqueous phase products (APs), as by-products of HTL, pose a risk of eutrophication for the high levels of carbon, nitrogen, and phosphorus. Supercritical water oxidation (SCWO) can efficiently convert organics into small molecules, offering a technique for the harmless treatment of APs. Effects of holding time, pressure, and moisture content on the biocrude yields from isothermal HTL (300 °C) and fast HTL (salt bath temperature of 500 °C) were comprehensively investigated. Biocrude properties were characterized by elemental analysis, FT-IR and GC-MS. Subsequently, the APs obtained under the conditions producing the highest biocrude yield were subjected to SCWO at 550 °C with different oxidation coefficients (n) from 0 to 2. Removal rates of chemical oxygen demand (COD), ammonia nitrogen (NH3-N), and total phosphorus (TP) were further explored. The results show that the highest biocrude yields from isothermal HTL and fast HTL were 24.2 wt% (300 °C, 1800 s, 25 MPa, and 80 wt% moisture content) and 21.9 wt% (500 °C, 40 s, 25 MPa, and 80 wt% moisture content), respectively. The biocrude primarily consisted of N-containing heterocyclic compounds, amides, and acids. SCWO effectively degraded the COD and TP in APs, while the NH3-N required further degradation. At n = 2, the highest removal rates of COD, NH3-N and TP were 98.5 %, 22.6 % and 89.1 %, respectively.

Clinical characteristics of outpatients with influenza-B-associated pneumonia and molecular evolution of influenza B virus in Beijing, China, during the 2021-2022 influenza season.

We analyzed the clinical characteristics of outpatients with influenza-B-associated pneumonia during the 2021-2022 influenza season and analyzed the molecular epidemiology and evolution of influenza B virus. The presence of influenza B virus was confirmed by reverse transcription polymerase chain reaction (RT-PCR). Electronic medical records were used to collect and analyze data of outpatients. The HA and NA genes were phylogenetically analyzed using ClustalW 2.10 and MEGA 11.0. Out of 1569 outpatients who tested positive for influenza B virus, 11.7% (184/1569) developed pneumonia, and of these, 19.0% (35/184) had underlying diseases. Fever, cough, and sore throat were the most common symptoms. Among the complications, acute respiratory distress syndrome (ARDS), acute kidney injury (AKI), and shock accounted for 2.7% (5/184), 4.9% (9/184), and 1.6% (3/184), respectively. Of the outpatients, 2.7% (5/184) were admitted to the hospital, and 0.5% (1/184) of them died. All of the strains from Beijing were identified as belonging to the B/Victoria lineage. The HA and NA gene sequences of 41 influenza B viruses showed high similarity to each other, and all of them belonged to clade 1A.3. Compared with the vaccine strain B/Washington/02/2019, all of the isolates contained N150K, G181E, and S194D mutations. S194D, E195K, and K200R mutations were detected in the 190 helix of the receptor binding region of HA. Co-mutations of H122Q, A127T, P144L, N150K, G181E, S194D, and K200R in HA and D53N, N59S, and G233E in NA were detected in 78.0% (32/41) of the isolates, and 56.3% (18/32) of these were from outpatients with influenza-B-associated pneumonia. Influenza outpatients with underlying diseases were more likely to develop pneumonia. No significant differences were observed in clinical symptoms or laboratory results between outpatients with and without pneumonia, so testing for influenza virus seems to be a good choice. The observed amino acid variations suggest that current vaccines might not provide effective protection.

Occurrence and source identification of antibiotics and antibiotic resistance genes in groundwater surrounding urban hospitals.

Urban groundwater, serving as a critical reservoir for potable water, faces susceptibility to contamination from discrete sources such as hospital wastewater. This study investigates the distribution and plausible origins of antibiotics and antibiotic resistance genes (ARGs) in urban groundwater, drawing comparisons between areas proximal to hospitals and non-hospital areas. Ofloxacin and oxytetracycline emerged as the prevalent antibiotics across all samples, with a discernibly richer array of antibiotic types observed in groundwater sourced from hospital-adjacent regions. Employing a suite of multi-indicator tracers encompassing indicator drugs, Enterococci, ammonia, and Cl/Br mass ratio, discernible pollution from hospital or domestic sewage leakage was identified in specific wells, correlating with an escalating trajectory in antibiotic contamination. Redundancy analysis underscored temperature and dissolved organic carbon as principal environmental factors influencing antibiotics distribution in groundwater. Network analysis elucidated the facilitating role of mobile genetic elements, such as int1 and tnpA-02 in propagating ARGs. Furthermore, ARGs abundance exhibited positive correlations with temperature, pH and metallic constituents (e.g., Cu, Pb, Mn and Fe) (p < 0.05). Notably, no conspicuous correlation manifested between antibiotics and ARGs. These findings accentuate the imperative of recognizing the peril posed by antibiotic contamination in groundwater proximal to hospitals and advocate for the formulation of robust prevention and control strategies to mitigate the dissemination of antibiotics and ARGs.

A strategy to boost xanthine oxidase and angiotensin converting enzyme inhibitory activities of peptides via molecular docking and module substitution.

Molecular docking and activity evaluation screened the dipeptide module GP with low xanthine oxidase (XOD) inhibitory activity and modules KE and KN with high activity, and identified them as low- and high-contribution modules, respectively. We hypothesized the substitution of low-contribution modules in peptides with high contributions would boost their XOD inhibitory activity. In the XOD inhibitory peptide GPAGPR, substitution of GP with both KE and KN led to enhanced affinity between the peptides and XOD. They also increased XOD inhibitory activity (26.4% and 10.3%) and decreased cellular uric acid concentrations (28.0% and 10.4%). RNA sequencing indicated that these improvements were attributable to the inhibition of uric acid biosynthesis. In addition, module substitution increased the angiotensin-converting enzyme inhibitory activity of GILRP and GAAGGAF by 84.8% and 76.5%. This study revealed that module substitution is a feasible strategy to boost peptide activity, and provided information for the optimization of hydrolysate preparation conditions.

Arsenic biogeochemical cycling association with basin-scale dynamics of microbial functionality and organic matter molecular composition.

Geogenic arsenic (As)-contaminated groundwater is a sustaining global health concern that is tightly constrained by multiple interrelated biogeochemical processes. However, a complete spectrum of the biogeochemical network of high-As groundwater remains to be established, concurrently neglecting systematic zonation of groundwater biogeochemistry on the regional scale. We uncovered the geomicrobial interaction network governing As biogeochemical pathways by merging in-field hydrogeochemical monitoring, metagenomic analyses, and ultrahigh resolution mass spectrometry (FT-ICR MS) characterization of dissolved organic matter. In oxidizing to weakly reducing environments, the nitrate-reduction and sulfate-reduction encoding genes (narGHI, sat) inhibited the dissolution of As-bearing iron minerals, leading to lower As levels in groundwater. In settings from weakly to moderately reducing, high abundances of sulfate-reduction and iron-transport encoding genes boosted iron mineral dissolution and consequent As release. As it evolved to strongly reducing stage, elevated abundance of methane cycle-related genes (fae, fwd, fmd) further enhanced As mobilization in part by triggering the formation of gaseous methylarsenic. During redox cycling of N, S, Fe, C and As in groundwater, As migration to groundwater and immobilization in mineral particles are geochemically constrained by basin-scale dynamics of microbial functionality and DOM molecular composition. The study constructs a theoretical model to summarize new perspectives on the biogeochemical network of As cycling.

Biological oxidation of As(III) and Sb(III) by a novel bacterium with Sb(III) oxidase rather than As(III) oxidase under anaerobic and aerobic conditions.

Sb and As are chemically similar, but the sequences and structures of Sb(III) and As(III) oxidase are totally distinct. It is thus interesting to explore whether Sb(III) oxidase oxidizes As(III), and if so, how microbial oxidations of Sb(III) and As(III) influence one another. Previous investigations have yielded ambiguous or even erroneous conclusions. This study aimed to clarify this issue. Firstly, we prepared a consortium of Sb(III)-oxidizing prokaryotes (SOPs) by enrichment cultivation. Metagenomic analysis reveals that SOPs with the Sb(III) oxidase gene, but lacking the As(III) oxidase gene are predominant in the SOP community. Despite this, SOPs exhibit comparable Sb(III) and As(III)-oxidizing activities in both aerobic and anaerobic conditions, indicating that at the microbial community level, Sb(III) oxidase can oxidize As(III). Secondly, we isolated a representative cultivable SOP, Ralstonia sp. SbOX with Sb(III) oxidase gene but without As(III) oxidase gene. Genomic analysis of SbOX reveals that this SOP strain has a complete Sb(III) oxidase (AnoA) gene, but lacks As(III) oxidase (AioAB or ArxAB) gene. It is interesting to discover that, besides its Sb(III) oxidation activities, SbOX also exhibits significant capabilities in oxidizing As(III) under both aerobic and anaerobic conditions. Moreover, under aerobic conditions and in the presence of both Sb(III) and As(III), SbOX exhibited a preference for oxidizing Sb(III). Only after the near complete oxidation of Sb(III) did SbOX initiate rapid oxidation of As(III). In contrast, under anaerobic conditions and in the presence of both Sb(III) and As(III), Sb(III) oxidation notably inhibited the As(III) oxidation pathway in SbOX, while As(III) exhibited minimal effects on the Sb(III) oxidation. These findings suggest that SOPs can oxidize As(III) under both aerobic and anaerobic conditions, exhibiting a strong preference for Sb(III) over As(III) oxidation in the presence of both. This study unveils a novel mechanism of interaction within the Sb and As biogeochemical cycles.

Understanding spatial heterogeneity of groundwater arsenic concentrations at a field scale: Taking the Datong Basin as an example to explore the significance of hydrogeological factors.

The spatial heterogeneity of arsenic (As) concentration exceeding the 10 µg/L WHO limit at the field scale poses significant challenges for groundwater utilization, but it remains poorly understood. To address this knowledge gap, the Daying site was selected as a representative case (As concentration ranged from 1.55 to 2237 µg/L within a 250 × 150 m field), and a total of 28 groundwater samples were collected and analyzed for hydrochemistry, As speciation, and stable hydrogen and oxygen isotope. Principal component analysis was employed to identify the primary factors controlling groundwater hydrochemistry. Results indicate that the spatial heterogeneity of groundwater As concentration is primarily attributed to vertical recharge and competitive adsorption. Low vertical recharge introduces reductive substances, such as dissolved organic matter, which enhances the reductive environment and facilitates microbial-induced reduction and mobilization of As. Conversely, areas with high vertical recharge introduce oxidizing agents like SO42- and DO, which act as preferred electron acceptors over Fe(III), thus inhibiting the reductive dissolution of Fe(III) oxides and the mobilization of As. PCA and hydrochemistry jointly indicate that spatial variability of P and its competitive adsorption with As are important factors leading to spatial heterogeneity of groundwater As concentration. However, the impacts of pH, Si, HCO3-, and F- on As adsorption are insignificant. Specifically, low vertical recharge can increase the proportion of As(III) and promote P release through organic matter mineralization. This process further leads to the desorption of As, indicating a synergistic effect between low vertical recharge and competitive adsorption. This field-scale spatial heterogeneity underscores the critical role of hydrogeological conditions. Sites with close hydraulic connections to surface water often exhibit low As concentrations in groundwater. Therefore, when establishing wells in areas with widespread high-As groundwater, selecting sites with open hydrogeological conditions can prove beneficial.

Achievements and challenges in improving air quality in China: Analysis of the long-term trends from 2014 to 2022.

Due to the implementation of air pollution control measures in China, air quality has significantly improved, although there are still additional issues to be addressed. This study used the long-term trends of air pollutants to discuss the achievements and challenges in further improving air quality in China. The Kolmogorov-Zurbenko (KZ) filter and multiple-linear regression (MLR) were used to quantify the meteorology-related and emission-related trends of air pollutants from 2014 to 2022 in China. The KZ filter analysis showed that PM2.5 decreased by 7.36 ± 2.92% yr-1, while daily maximum 8-h ozone (MDA8 O3) showed an increasing trend with 3.71 ± 2.89% yr-1 in China. The decrease in PM2.5 and increase in MDA8 O3 were primarily attributed to changes in emission, with the relative contribution of 85.8% and 86.0%, respectively. Meteorology variations, including increased ambient temperature, boundary layer height, and reduced relative humidity, also contributed to the reduction of PM2.5 and the enhancement of MDA8 O3. The emission-related trends of PM2.5 and MDA8 O3 exhibited continuous decrease and increase, respectively, from 2014 to 2022, while the variation rates slowed during 2018-2020 compared to that during 2014-2017, highlighting the challenges in further improving air quality, particularly in simultaneously reducing PM2.5 and O3. This study recommends reducing NH3 emissions from the agriculture sector in rural areas and transport emissions in urban areas to further decrease PM2.5 levels. Addressing O3 pollution requires the reduction of O3 precursor gases based on site-specific atmospheric chemistry considerations.

Three-dimensional glass scaffolds improve the In Vitro maturation of porcine cumulus-oocyte complexes and subsequent embryonic development after parthenogenetic activation.

In vitro maturation (IVM) methods for porcine oocytes are still deficient in achieving full developmental capacity, as the currently available oocyte in vitro culture systems still have limitations. In vitro embryo production must also improve the porcine oocyte IVM system to acquire oocytes with good developmental potential. Herein, we tested a three-dimensional (3D) glass scaffold culture system for porcine oocyte maturation. After 42 h, we matured porcine cumulus-oocyte complexes (COCs) on either two-dimensional glass dishes (2D-B), two-dimensional microdrops (2D-W), or 3D glass scaffolds. The 3D glass scaffolds were tested for porcine oocyte maturation and embryonic development. Among these culture methods, the extended morphology of the 3D group maintained a 3D structure better than the 2D-B and 2D-W groups, which had flat COCs that grew close to the bottom of the culture vessel. The COCs of the 3D group had a higher cumulus expansion index and higher first polar body extrusion rate, cleavage rate, and blastocyst rate of parthenogenetic embryos than the 2D-B group. In the 3D group, the cumulus-expansion-related gene HAS2 and anti-apoptotic gene Bcl-2 were significantly upregulated (p < 0.05), while the pro-apoptotic gene Caspase3 was significantly downregulated (p < 0.05). The blastocysts of the 3D group had a higher relative expression of Bcl-2, Oct4, and Nanog than the other two groups (p < 0.05). The 3D group also had a more uniform distribution of mitochondrial membrane potential and mitochondria (p < 0.05), and its cytoplasmic active oxygen species content was much lower than that in the 2D-B group (p < 0.05). These results show that 3D glass scaffolds dramatically increased porcine oocyte maturation and embryonic development after parthenogenetic activation, providing a suitable culture model for porcine oocytes.

Supplemental low-dose esketamine to propofol versus propofol alone on perioperative characteristics in children undergoing surgery: a prospective randomized controlled trial.

BACKGROUND: Limited data exist regarding the use of the esketamine-propofol combination (esketofol) in pediatric surgery. This study aimed to investigate the effect of esketofol versus propofol alone on the perioperative characteristics of children undergoing minor surgery. METHODS: Eighty-four children aged two to six years were randomly assigned to either the propofol group or the esketofol group. Intraoperative outcomes included bispectral index, dosage of anesthetics, and extubation time. Postoperative outcomes comprised oropharyngeal airway usage, time to orientation, time to eye-opening, length of stay in the post-anesthesia care unit, the need for rescue opioids, pain rating using the Face, Legs, Activity, Cry, Consolability (FLACC) Scale, Pediatric Anesthesia Emergence Delirium Score, nausea and vomiting, and psychotomimetic symptoms. The FLACC pain score was the primary outcome, and the remaining parameters were considered secondary outcomes. RESULTS: The FLACC Score (2 [1, 3.3] vs. 4 [3, 5.3], P<0.001) and frequency of rescue opioids (14.3% vs. 33.3%, P=0.040) were significantly lower, while Bispectral Index (BIS) was higher (P<0.001) in the esketofol group compared with the propofol group. Moreover, the time to orientation and length of stay in the post-anesthesia care unit (PACU) were significantly longer in the esketofol group compared with the propofol group (P=0.029 and P=0.025, respectively). The other outcomes were similar between the two groups. CONCLUSIONS: Esketofol reduces postoperative pain and the need for rescue opioids, but it extends recovery time in the PACU and increases BIS without affecting other outcomes.

Characteristics of dissolved organic matter contribute to Geogenic ammonium enrichment in coastal versus alluvial-lacustrine aquifers.

Elevated concentration levels of geogenic ammonium in groundwater arise from the mineralization of nitrogen-containing natural organic matter in various geological settings worldwide, especially in alluvial-lacustrine and coastal environments. However, the difference in enrichment mechanisms of geogenic ammonium between these two types of aquifers remains poorly understood. To address this knowledge gap, we investigated two representative aquifer systems in central Yangtze (Dongting Lake Plain, DTP) and southern China (Pearl River Delta, PRD) with contrasting geogenic ammonium contents. The use of optical and molecular characterization of DOM combined with hydrochemistry and stable carbon isotopes has revealed differences in DOM between the two types of aquifer systems and revealed contrasting controls of DOM on ammonium enrichment. The results indicated higher humification and degradation of DOM in DTP groundwater, characterized by abundant highly unsaturated compounds. The degradation of DOM and nitrogen-containing DOM was dominated by highly unsaturated compounds and CHO+N molecular formulas in highly unsaturated compounds, respectively. In contrast, the DOM in PRD groundwater was more biogenic, less degraded, and contained more aliphatic compounds in addition to highly unsaturated compounds. The degradation of DOM and nitrogen-containing DOM was dominated by aliphatic compounds and polyphenols and CHO+N molecular formulas in highly unsaturated compounds and polyphenols, respectively. As DOM degraded, the ammonium production efficiency of DOM decreased, contributing to lower ammonium concentrations in DTP groundwater. In addition, the CHO+N(SP) molecular formulas were mainly of microbial-derived and gradually accumulated with DOM degradation. In this study, we conducted the first comprehensive investigation into the patterns of groundwater ammonium enrichment based on DOM differences in various geological settings.