Impacts of O2:CH4 ratios and CH4 concentrations on the denitrification and CH4 oxidations of a novel AME-AD system.

Aerobic methane (CH4) oxidation coupled to denitrification (AME-D) is a promising process for the denitrification of low C/N wastewater. Compared with anaerobic denitrifying bacteria, aerobic denitrifying bacteria may enable AME-D have high denitrification ability under aerobic conditions. This study constructed a novel aerobic methane oxidation coupled to aerobic denitrification (AME-AD) system using the typical aerobic denitrifying bacteria Paracoccus pantotrophus ATCC35512 and the typical aerobic methane oxidizing bacteria Methylosinus trichosporium OB3b. The denitrification and CH4 oxidations of AME-AD with different O2:CH4 ratios (0:1, 0.25:1, 0.5:1, 0.75:1, 1:1 and 1.25:1) and CH4 concentrations (0, 14000, 28000, 42000, 56000 and 70000 mg m-3) were investigated in batch experiments. Higher O2:CH4 ratios can significantly improve the denitrification and CH4 oxidations of the AME-AD (P < 0.05). The treatment with an O2:CH4 ratio of 1.25:1 had the highest denitrification rate (0.036 mg h-1) and highest CH4 oxidation rate (0.20 mg h-1). The CH4 concentration in the headspace was positively correlated with the AME-AD denitrification rate. The calculated CH4/NO3-(mol/mol) in most treatments ranged from 5.76 to 6.84. In addition, excessively high O2 and CH4 concentrations can lead to increased nitrous oxide (N2O) production in AME-AD. The N2O production rate was up to 1.00 µg h-1 when the O2:CH4 was 1.25:1. These results can provide data support for the application of AME-AD for low-C/N wastewater treatment and greenhouse gas emission reduction.

Separation efficiency of different solid-liquid separation technologies for slurry and gas emissions of liquid and solid fractions: A meta-analysis.

Solid-liquid separation (SLS) technology is widely used in the slurry management in animal farms. This study conducted a comprehensive meta-analysis of 45 published articles to evaluate the differences in separation efficiencies (SEX-SF) of various SLSs and the changes of gas emissions before and after the separation during on-farm slurry storage. The results indicated that the SEX-SF of the untreated raw slurry and acidified slurry were consistently greater than those of the digested slurry, and centrifugation resulted in greater SEX-SF than the other mechanical methods. Both measured and simulated data showed that the centrifuge technology had greater reductions in greenhouse gas (GHG) emissions relative to the screw press (56.1-58.0% vs. 38.9-40.2% for untreated slurry, and 29.7-30.2% vs. 22.5-23.2% for digested slurry), mainly due to CH4 reduction. Additionally, we identify the need for further assessment of the environmental risks that are associated with SLSs for the development of an optimal slurry management chain.

Impacts of slurry application methods and inhibitors on gaseous emissions and N2O pathways in meadow-cinnamon soil.

This study aimed to evaluate the impact of mitigation practices (slurry application methods and inhibitors applications) on gas emissions and identify the soil N2O production pathways in cattle slurry applied soil using isotopocule mapping approach. First, we compared the NH3 and N2O emissions of cattle slurry applied soil in a summer maize field experiment in north China plain (NCP) with four treatments: control (CK, no fertilization), slurry application using surface (SA-S), slurry application using band application (BA-S), and chemical fertilizer application using band application (BA-C). Then, an incubation experiment was conducted to investigate the mitigation effect of nitrification inhibitors (dicyandiamide, DCD) and denitrification inhibitors (procyanidins, PC) and their combination (DCD + PC) on gaseous N emissions with slurry applied using incorporation (IA) or surface application (SA) methods. The results showed that the total gaseous N emissions (N2O-N and NH3-N) in field were in the order of SA-S (1534 mg m-2) > BA-S (338 mg m-2) > BA-C (128 mg m-2) > CK (55 mg m-2), and the dominant N loss contributor varied from NH3 in SA-S (∼89%) to N2O in BA-S (∼94%) and BA-C (∼88%). Moreover, the isotopocule mapping approach indicated that emitted N2O of the slurry applied soil in field appeared to have lower rN2O values and led to more N2O + N2 emissions at the initial fertilization period. The incubation experiment indicated that the N2O emissions of slurry-applied soil were significantly reduced by DCD (∼45%) and DCD + PC (∼67%) application in comparison with CK (p < 0.05), and the stronger contributions of bacterial denitrification/nitrifier denitrification to N2O production were revealed by the lower δ15NSP in N2O using the isotopocule mapping approach. In conclusion, in NCP the gaseous losses of the slurry applied field can be largely reduced by using incorporation method, and greater reduction could be achieved given the simultaneous application of nitrification/denitrification inhibitors.

Exploratory research on influential factors of China's sulfur dioxide emission based on symbolic regression.

The amount of China's sulfur dioxide emission remains significantly large in recent years. To further reduce sulfur dioxide emission, the key is to find out the leading factors affecting sulfur dioxide emission and then take measures to control it accordingly. In order to investigate the influential factors of sulfur dioxide emission of various provinces, the data of sulfur dioxide emission of 30 provinces in China from 2001 to 2020 were collected. We established the symbolic regression model to explore the relationship between the GDP (x1), total population (x2), total energy consumption (x3), thermal power installed capacity (x4), and sulfur dioxide emission (dependent variable) for each province. The results show that the amount of China's total sulfur dioxide emission and sulfur dioxide emission in most provinces meet the environmental Kuznets curve (EKC). The influential degree of the factors affecting China's sulfur dioxide emission are GDP, total energy consumption, thermal power installed capacity, and total population. The provinces with the primary factor of GDP have the lowest average total energy consumption and average thermal power installed capacity, and their average sulfur dioxide emissions are also relatively low. The provinces with the primary factor of GDP do not show obvious geographical characteristics, but the provinces with the primary factor of total energy consumption are all distributed in southern China. Based on the research results, some control measures are also put forward.

Understanding the Reduction of Transition-Metal Phosphates to Transition-Metal Phosphides by Combining Temperature-Programmed Reduction and Infrared Spectroscopy.

Temperature-programmed reduction of transition-metal phosphate precursors is the most commonly used method for the preparation of transition-metal phosphides (a new class of versatile metal catalysts), but the reduction processes are still not clear. Here we describe the construction of a temperature-programmed reduction-infrared spectroscopy apparatus (TPR-IR) to analyze the gas flows during the reduction of nickel, molybdenum, and tungsten phosphates. PH3 and Pn+ species already appeared in the gas flows at low temperature (ca. 200 °C), and PH3 was involved in the formation of phosphides. The emission of PH3 and Pn+ during the reduction of the molybdenum and tungsten phosphates was smaller than that of the nickel phosphate. Ni2 P drastically accelerated the formation of the PH3 and Pn+ . These results explain why excess phosphorus is needed for the preparation of Ni2 P, and also demonstrate that the TPR-IR technique is an efficient method to understand the complex processes of catalyst preparation.

Purification efficiency of zeolite and two planted grasses on sewage and relationship with carbon-nitrogen-phosphorus ratios in simulated constructed wetland system.

For achieving the economical and efficient configuration of constructed wetlands (CWs), a simulated device of vertical flow CWs was used to investigate the effects of different volume ratios of substrates to two cold-resistant plants on pollutant concentrations as well as their ratios in effluent under different inflow domestic sewage concentrations. The average removal rates (ARRs) of ammonia nitrogen, total nitrogen (TN) and total phosphorus were 82.7%, 84.9% and 80.6% respectively in the treatments with zeolite but no plants, which increased by 22.6%, 20.8% and 14.9% compared with those without zeolite and plants. However, in the treatments with zeolite and planted grasses, the ARRs of the three pollutants were over 90%, and those of chemical oxygen demand were lower. The removal rates of ammonia nitrogen, TN and total phosphorus had negative correlations with C:N and N:P ratios and positive correlations with the C:P ratios. Increasing the ratio of zeolite to soil from 1:1 to 2:1 had no significant effects in the removal efficiency. It was suggested that planting Lolium perenne or Poa annua on the substrate with a zeolite to soil volume ratio of 1:1 could be considered as the optimum combination to purify the domestic sewage in north rural areas of China.

Characterization of a novel p110ß-specific inhibitor BL140 that overcomes MDV3100-resistance in castration-resistant prostate cancer cells.

BACKGROUND: Our previous studies demonstrated that the class IA PI3K/p110ß is critical in castration-resistant progression of prostate cancer (CRPC) and that targeting prostate cancer with nanomicelle-loaded p110ß-specific inhibitor TGX221 blocked xenograft tumor growth in nude mice, confirming the feasibility of p110ß-targeted therapy for CRPCs. To improve TGX221's aqueous solubility, in this study, we characterized four recently synthesized TGX221 analogs. METHODS: TGX221 analog efficacy were examined in multiple prostate cancer cell lines with the SRB cell growth assay, Western blot assay for AKT phosphorylation and cell cycle protein levels. Target engagement with PI3K isoforms was evaluated with cellular thermal shift assay. PI3K activity was determined with the Kinase-Glo Plus luminescent kinase assay. Cell cycle distribution was evaluated with flow cytometry after propidium iodide staining. RESULTS: As expected, replacing either one of two major functional groups in TGX221 by more hydrophilic groups dramatically improved the aqueous solubility (about 40-fold) compared to TGX221. In the CETSA assay, all the analogs dramatically shifted the melting curve of p110ß protein while none of them largely affected the melting curves of p110α, p110γ, or Akt proteins, indicating target-specific engagement of these analogs with p110ß protein. However, functional evaluation showed that only one of the analogs BL140 ubiquitously inhibited AKT phosphorylation in all CRPC cell lines tested with diverse genetic abnormalities including AR, PTEN, and p53 status. BL140 was superior than GSK2636771 (IC50 5.74 vs 20.49 nM), the only p110ß-selective inhibitor currently in clinical trials, as revealed in an in vitro Kinase-Glo assay. Furthermore, BL140 exhibited a stronger inhibitory effect than GSK2636771 on multiple CRPC cell lines including a MDV3100-resistant C4-2B cell subline, indicating BL140 elimination of MDV3100 resistance. Mechanistic studies revealed that BL140 blocked G1 phase cell cycle entry by reducing cyclin D1 but increasing p27kip1 protein levels. CONCLUSION: These studies suggested that BL140 is a promising p110ß-specific inhibitor with multiple superb properties than GSK2636771 worthy for further clinical development.

Effects of color centers absorption on the spectrum of the temperature-dependent radiation-induced attenuation in fiber.

Spectra ranging from 800 to 1650 nm of the temperature-dependent radiation-induced attenuation (RIA) in the irradiated and sufficiently annealed fiber with germanium and phosphorous dopant has been measured. These RIA spectra were investigated based on the mechanism of color centers absorption. With the configurational coordinate model, these RIA spectra were decomposed by the absorption bands of three kinds of color centers. The effects of color centers absorption on the spectrum of temperature-dependent RIA is discussed by comparing the absorption intensity of different color centers at a same wavelength. Moreover, the temperature-dependent RIA of the fiber has been measured separately at 850, 1310, and 1550 nm. The measured results agreed well with the analysis of RIA spectra.

Therapeutic drug monitoring of perampanel: Clinical utility and impact of co-medication on pharmacokinetic variability.

Background: Perampanel (PER) is a newly developed antiseizure medication (ASM). This study aimed to determine the utilization of therapeutic drug monitoring (TDM) for PER in a real-world clinical setting and investigate the influence of concomitant use of ASMs on the plasma concentration profile of PER. Method: We analyzed data from the Chang Gung Research Database, which is the largest multi-institutional electronic medical records database in Taiwan. The main outcomes were the comparisons of PER plasma concentration and the ratio of concentration to the weight-adjusted dose (C/D; [ng/mL]/[mg/kg/d]) among patients received TDM of different clinical indication and among different ASM co-medication subgroups. Results: Overall, 88 plasma samples were collected from 66 epilepsy patients treated with PER. The majority of patients (77.3 %) underwent PER TDM owing to poorly controlled seizures. There was a trend toward a higher plasma concentration and C/D ratio in those suspected of having PER toxicity owing to adverse events than of other indications. The PER concentration exhibited dose linearity. The mean PER plasma concentrations in patients co-medicated with enzyme-inducing ASMs were significantly lower than those in the patients who were not prescribed enzyme-inducing or enzyme-inhibiting ASMs, and co-medication with carbamazepine (CBZ) resulted in a significant reduction in the PER concentration. Conclusion: PER concentration exhibited a linear regression relationship with PER dose, and the plasma concentration of the drug was highly susceptible to the drug's interactions with enzyme-inducing ASMs. TDM with clear indication could help determine the influence of ASMs used concomitantly on PER concentrations and guide clinical adjustments.

Exploring the factors effecting on carbon emissions in each province in China: A comprehensive study based on symbolic regression, LMDI and Tapio models.

Carbon emission (CE) has led to increasingly severe climate problems. The key to reducing CE is to identify the dominant influencing factors and explore their influence degree. The CE data of 30 provinces from 1997 to 2020 in China were calculated by IPCC method. Based on this, the importance order of six factors included GDP, Industrial Structure (IS), Total Population (TP), Population Structure (PS), Energy Intensity (EI) and Energy Structure (ES) affecting the CE of China's provinces were obtained by using symbolic regression, then the LMDI and the Tapio models were established to deeply explore the influence degree of different factors on CE. The results showed that the 30 provinces were divided into five categories according to the primary factor, GDP was the most important factor, followed by ES and EI, then IS, and the least TP and PS. The growth of per capita GDP promoted the increase of CE, while reduced EI inhibited the increase of CE. The increase of ES promoted CE in some provinces but inhibited in others. The increase of TP weakly promoted the increase of CE. These results can provide some references for governments to formulate relevant CE reduction policies under dual carbon goal.

Association of Long-term Antiseizure Medication Use and Incident Type 2 Diabetes Mellitus.

BACKGROUND AND OBJECTIVES: Diabetes mellitus (DM) contributes significantly to metabolic syndrome and cardiovascular events, and it may be a comorbidity of epilepsy. The objective of this study was to investigate whether long-term antiseizure medication (ASM) use is associated with the risk of developing type 2 diabetes. METHODS: We analyzed data from the Chang Gung Research Database. Patients aged ≥45 years who received ASM treatment from January 2001 to May 2019 were identified. Patients with DM-associated diseases and short-term ASM use were excluded. The patients were classified into nonenzyme interaction, enzyme-inducing, enzyme-inhibiting, and mixed ASM groups. The rate of incident diabetes associated with individual ASM was further analyzed. Propensity score weighting was performed to balance between-group differences. Analyses were conducted with Cox proportional regression models and stabilized inverse probability of treatment weighting (IPTW). Hazard ratios (HRs) were calculated at 3, 4, 6, and 9 years after the index date and the end of follow-up. RESULTS: A total of 5,103 patients were analyzed, of whom 474 took nonenzyme interaction ASMs, 1,156 took enzyme-inducing ASMs, 336 took enzyme-inhibiting ASMs, and 3,137 took mixed ASMs. During follow-up (39,248 person-years), 663 patients developed new-onset DM, and the prevalence was 13.0%. The incidence of DM plateaued at 6-9 years after ASM initiation. Enzyme-inhibiting ASMs were significantly associated with a higher HR starting at the third year and then throughout the study period. The HRs were 1.93 (95% CI 1.33-2.80), 1.85 (95% CI 1.24-2.75), and 2.08 (95% CI 1.43-3.03) in unadjusted, adjusted, and stabilized IPTW models, respectively, at the end of follow-up. The dosing of ASM did not increase the risk of DM, and none of the individual ASM analyses reached statistical significance. DISCUSSION: The long-term use of enzyme-inhibiting ASMs was associated with an increased risk of incident DM, and the risk increased with the duration of treatment. These findings may guide the choice of drugs in those requiring long-term ASM therapy, particularly in high-risk individuals. CLASSIFICATION OF EVIDENCE: This study provides Class IV evidence that enzyme-inhibiting ASMs were associated with an increased risk of developing DM compared with nonenzyme interaction ASMs.

Optimizing treatment persistence in epilepsy: a comparative analysis of combined antiseizure medications with different mechanisms of action.

Background: Combination therapy with antiseizure medications (ASMs) is a rational strategy if monotherapy cannot effectively control seizures, thereby aiming to improve tolerance and treatment persistence. Objectives: To compare the efficacy of different ASM combinations among patients. Design: Patients with epilepsy on monotherapy who had a second ASM added as concomitant two-drug therapy from January 2009 to May 2019 in the Chang Gung Research Database, Taiwan, were included in the analysis. Methods: ASM combinations were compared based on their primary mechanism of action (MoA) which are as follows: gamma-aminobutyric acid receptor (G), sodium channel blocker (SC), synaptic vesicle protein 2A (SV2), calcium channel blocker (C), and multiple mechanisms (M). Treatment persistence was compared, and the predictors of persistence were analyzed. Results: In total, 3033 patients were enrolled in this study. Combined ASMs with different MoAs had significantly longer treatment persistence than ASMs with similar MoAs, specifically SC and M combinations. Patients receiving combined ASMs with different MoAs were less likely to discontinue treatment [adjusted hazards ratio: 0.83 (95% CI: 0.75-0.93), p < 0.001]. Among all combinations, the SC + SV2 combination had the longest treatment persistence (mean ± SD: 912.7 ± 841.6 days). Meanwhile, patients receiving the G combination had a higher risk of treatment discontinuation than those receiving the SC + SV2 combination. Underlying malignancies were associated with an increased risk of treatment discontinuation across all MoA categories. Male patients receiving the SC, SV2, and M combinations were more likely to discontinue treatment than female patients. Moreover, patients with renal disease were more likely to discontinue treatment with the SV2 combinations. Conclusion: ASM combinations with different MoAs had superior efficacy and tolerability to ASM combinations with similar MoAs, particularly SC and M combinations. In our cohort, factors associated with treatment discontinuation included underlying malignancy, male sex, and renal disease. These findings may provide valuable insights into the use of ASM combinations if monotherapy cannot adequately control seizures.

Juvenile Myoclonic Epilepsy: Seizure and Social Outcomes in Taiwan.

Patients with juvenile myoclonic epilepsy (JME) may not achieve seizure freedom despite optimal treatment with antiseizure medications (ASMs). The aim of this study was to investigate the clinical and social features of patients with JME, and to determine the factors associated with outcomes. We retrospectively identified 49 patients with JME (25 females, mean age 27.6 ± 8.9 years) who were assessed at the Epilepsy Centre of Linkou Chang Gung Memorial Hospital in Taiwan. The patients were divided into two groups, those who were seizure-free and those with ongoing seizures according to their seizure outcome at the last follow-up for one year. Clinical features and social status were compared between these two groups. Twenty-four (49%) of the JME patients were seizure-free for at least one year, while 51% continued to experience seizures despite being treated with multiple ASMs. The presence of epileptiform discharges in the last electroencephalogram and seizures during sleep were significantly associated with worse seizure outcomes (p < 0.05). The patients who were seizure-free had a higher employment rate compared to those who continued to experience seizures (75% vs. 32%, p = 0.004). Despite receiving ASM treatment, a considerable proportion of the patients with JME continued to have seizures. Moreover, poor seizure control was associated with a lower employment rate, which may lead to negative socioeconomic consequences related to JME.

Clinical impact of therapeutic drug monitoring for newer anti-seizure medications in patients with epilepsy: A real-world observation study.

BACKGROUND: The clinical value of therapeutic drug monitoring (TDM) for newer anti-seizure medications (ASMs) remains uncertain. This study aimed to assess the impact of newer ASM TDM on clinical decision making in patients with epilepsy. METHODS: We retrospectively identified all plasma requests for newer ASM level measurement as part of routine clinical management in the outpatient departments of seven medical institutes across Taiwan between September 2016 and May 2019. Data collected from reviewed medical records included clinical and medication details, indications for TDM request, test results, interpretation, and impact on patient management. RESULTS: A total of 682 visits with 1051 plasma samples were included. The most frequently analyzed ASMs were levetiracetam (36.1%), oxcarbazepine (18.4%), and lamotrigine (12.0%). Reasons for TDM included poorly controlled seizures (55.3%), concerns about drug-drug interactions (12.3%), and suspicion of drug overdose (10.6%). 68.8% of samples were within the orienting therapeutic range, even for patients with poorly controlled seizures. TDM for non-adherence concerns showed 54.3% below the orienting therapeutic range, while ASM-related adverse events assessment only 8.9% showed levels exceeding the orienting therapeutic range. Following TDM results, 64.2% of cases had medication adjustments, mainly dosage increases. Overall, 55.9% of newer ASM TDM visit showed improved outcomes, including reduced seizures (47.5%) and fewer ASM-related side effects (8.4%). CONCLUSIONS: These findings suggest that appropriate utilization of TDM for newer ASMs provides clinical benefits in adjunct to complement clinical decision making in the management of epilepsy patients in a real-world clinical setting.

Prodrug strategy for PSMA-targeted delivery of TGX-221 to prostate cancer cells.

TGX-221 is a potent, selective, and cell membrane permeable inhibitor of the PI3K p110ß catalytic subunit. Recent studies showed that TGX-221 has antiproliferative activity against PTEN-deficient tumor cell lines including prostate cancers. The objective of this study was to develop an encapsulation system for parenterally delivering TGX-221 to the target tissue through a prostate-specific membrane aptamer (PSMAa10) with little or no side effects. In this study, PEG-PCL micelles were formulated to encapsulate the drug, and a prodrug strategy was pursued to improve the stability of the carrier system. Fluorescence imaging studies demonstrated that the cellular uptake of both drug and nanoparticles was significantly improved by targeted micelles in a PSMA positive cell line. The area under the plasma concentration time curve of the micelle formulation in nude mice was 2.27-fold greater than that of the naked drug, and the drug clearance rate was 6.16-fold slower. These findings suggest a novel formulation approach for improving site-specific drug delivery of a molecular-targeted prostate cancer treatment.

Construction of Garden Landscape Design System Based on Multimodal Intelligent Computing and Deep Neural Network.

The problem of module discrimination and identification in the field of landscape design is the focus of researchers. Based on multimodal intelligent computing, this paper constructs a landscape design system based on deep neural network. The article first uses a deep neural network to train multimodal garden landscape images, and then performs pooling and convolution operations on garden landscape images on the multimodal training model of convergence speed on the edge and solve the problem of low model accuracy. In the simulation process, the neural network module of MATLAB software is used to extract the spatiotemporal features of the dynamic garden landscape image from the three directions of the bottom block of the garden to achieve feature complementarity. This method only uses 15% of the features of the original feature set. The complexity of the recognition system also reduces the recognition error rate. The experimental results show that by adopting the design of feature series fusion, maximum value fusion, and multiplicative fusion in the score layer, the feature series fusion achieves a high accuracy rate under the multiplicative fusion of the three modalities, reaching 77.1%, and the test error is within 0.118, which effectively improves the multimodal characteristics of the integrated landscape and makes the modeling results more accurate.

Association of screen exposure with psychosocial problems in primary school students.

Introduction: This study aimed to investigate the current status of screen exposure and the factors related to screen exposure in primary school students and explore the relationship between screen exposure and psychosocial problems, which may provide evidence for the scientific use of electronic products and psychological interventions used in these children. Methods: The parents of 811 primary school students aged 6-12 years received a questionnaire survey in Beijing between January 13 and January 16, 2022. The demographic data and daily screen exposure time were collected, and the Strengths and Difficulties Questionnaire (SDQ) about their children was administered online. Results: In 793 students, the average daily screen exposure of <2 h and ≥2 h was noted in 75.0% and 25% of patients, respectively. The mobile phone was the main medium for screen exposure (40.9%). The family's economic level, parental relationship, and main supervisor were related to screen exposure time (χ 2 = 44.8,14.5 and 12.4, P < 0.05). A low family economic level with a monthly income not meeting the basic living needs, poor parental relationship, and an elderly person responsible for supervision were related to increased screen exposure time. The abnormal emotional and behavioral symptoms, conduct problems, hyperactivity inattention, peer communication, prosocial behaviors, and a total difficulties score were found in 11.6%, 9.8%, 15.3%, 22.1%, 6.8%, and 13.4% of children, respectively. Excessive screen exposure was related to peer interaction and prosocial behaviors (χ 2 = 12.18 and 7.76, P < 0.05). The children with excessive screen exposure were more likely to have abnormal peer interaction (χ 2 = 12.09, P = 0.001) and prosocial behaviors (χ 2 = 7.76, P = 0.005). Excessive screen exposure was a risk factor for peer interaction problems (P < 0.05). Discussion: In conclusion, the detection rate of excessive screen exposure is higher in primary school students, which is related to the family's economic level, parental relationship, and main supervisor. Excessive screen exposure is harmful to the psychosocial health of these children, which is characterized by abnormal peer intercommunion and prosocial behaviors. More attention should be paid to screen exposure time in primary school students.

Biodegradation of Dibutyl Phthalate by the New Strain Acinetobacter baumannii DP-2.

Optimizing the culture conditions of DBP degradation by bacteria and investigating its biodegradation pathways have a great importance to develop effective PAEs pollution control strategies. In this study, we investigated the cultivation condition optimization, degradation kinetics, and degradation pathways of a newly isolated dibutyl phthalate (DBP) degradation strain, which was isolated from activated sludge and identified as Acinetobacter baumannii DP-2 via morphological observation, biochemical identification, and 16S rDNA sequence analysis. The degradation conditions were optimized based on the results of single-factor experiments and response surface optimization experiments. The DBP degradation rate of Acinetobacter baumannii DP-2 reached up to 85.86% when the inoculation amount was 17.14%, the DBP concentration was 9.81 mg·L-1 and the NaCl concentration was 5 g·L-1. The GC-MS analysis results indicated that the intermediate metabolites of Acinetobacter baumannii DP-2 mainly consisted of DMP, MBP, PA, and benzoic acid derivatives, which confirmed the degradation pathway from DBP to PA under aerobic pathway and then to BA under anaerobic pathway. In summary, Acinetobacter baumannii DP-2 shows great potential for the degradation of DBP in contaminated soils.

Effects of methyl halide flux characteristics following Spartina alterniflora invasion in a seaward direction in a temperate salt marsh, China.

In this study, we explored the source-sink characteristics of methyl halide (CH3X; X = Cl, Br, I) in coastal wetlands located in temperate regions, and identified key factors affecting the spatio-temporal variation of CH3X during the invasion of Spartina alterniflora. We used static chamber-gas chromatography to monitor CH3X fluxes in the S. alterniflora area and bare flat area of the Jiaozhou Bay salt marsh for a long time from August 2015 to May 2017. Our results indicated that CH3X emissions showed obvious seasonal and diurnal variations. The S. alterniflora area was a source of CH3X, with higher fluxes in the spring and autumn seasons. CH3X fluxes were higher during the daytime than at night, and the diurnal difference in CH3Br was the most significant (4.51 times). The bare flat area was mainly a sink for CH3X, and the maximum absorption flux occurred in summer. At this time, the microbial activity was greater, and the consumption rate during the day was higher than that at night. Extreme linear correlations existed between the fluxes of CH3Cl, CH3Br, and CH3I (P < 0.01), indicating that the production and consumption of the three gases were likely to have similar mechanisms and were affected by the same factors. S. alterniflora invasion increased CH3X emissions and shifted the original bare flat area from a sink to a source of CH3X. The biomass of S. alterniflora, especially the leaf, significantly affects CH3X fluxes. Additionally, S. alterniflora increased the content of total organic carbon, total sulfur, available sulfur, and iron (III) in the soil, which were the main factors promoting the source-sink transformation of CH3X. Based on the current invasive area of S. alterniflora in China, we estimated that the annual emissions of CH3Cl, CH3Br, and CH3I from S. alterniflora into the troposphere were 9.04 × 106, 2.42 × 105 and 2.06 × 105 mol, respectively.

Mitigating gas emissions from poultry litter composting with waste vinegar residue.

The composting process is important in the recycling of organic wastes produced in agriculture, food, and municipal waste management. This study explored the suitability of using waste vinegar residue (WVR) as an amendment in poultry litter (PL) composting. Four treatments, including poultry litter (CK), poultry litter+vinegar residue (VR), poultry litter+vinegar residue+lime (VR_Ca) and poultry litter+vinegar residue+biochar (VR_B), were conducted. During a 42-day composting period, the dynamics of carbon dioxide (CO2), ammonia (NH3), nitrous oxide (N2O) and methane (CH4) emissions, as well as the physicochemical properties and abundances of the bacteria and fungi of the feedstock were tracked to examine the potential barriers in the co-composting of WVR and PL. Compared to those of the CK, using a WVR amendment lowered the pH, increased the electrical conductivity significantly at the early stage, resulted in a strong inhibition of bacterial and fungal growth and delayed the thermophilic period of poultry litter composting while significantly reducing NH3 and N2O and GHG (CO2-e) emissions. A preadjustment of the WVR with alkaline biochar or lime lengthened the thermophilic period and increased the germination index (GI) by alleviating the inhibitory effect of the WVR on bacterial and fungal growth during composting. However, such preadjustment might reduce the mitigation effect on NH3. In conclusion, WVR can be recycled through co-composting with poultry litter, and the additional mitigation of N losses and N conservation can be achieved without halting compost quality.