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Back mixing was frequently used to replace conventional bulking agenting, however, however, the internal effect mechanism was unclear. This study compared four bulking agents: mushroom residue (MR), MR + primary BM (BM-P), BM-P, and secondary BM (BM-S). The effect mechanism of back mixing (BM) inoculation was assessed based on biodrying performance and microbial community succession. Four trials (Trial A, Trial B, Trial C, and Trial D) reached maximum temperatures of 61.9, 68.8, 73.7, and 69.9 °C on days 6, 3, 2, and 2, respectively. Application of BM increased pile warming rate and resulted in higher temperatures. Temperature changes and microbial competition lead to decline in microbial diversity and richness during the biodrying process. Microbial diversity increased of four biodried products. The number of microorganisms shared by Trial A, Trial B, Trial C, and Trial D were 90, 119, 224, and 300, respectively. The addition of BM improved microbial community stability, and facilitating the initiation of biodrying process. Microbial genera that played an important role in the biodrying process included Ureibacillus, Bacillus, Sphaerobacter, and Tepidimicrobium. Based on these results, it was concluded that BM was efficient method to enhanced the microbial activity and reduced the usage of bulking agent.

Composting is an efficient and cost-effective technology for sewage sludge treatment, and bulking agents are essential in sewage sludge composting. In this study, perlite was chosen as inorganic bulking agent to partially substitute for the organic bulking agent. Variations in the temperature, bulk density, moisture content, pH, electrical conductivity, organic carbon, nitrogen, phosphorus and potassium were detected during sewage sludge composting. The treatment with a mass ratio of spent mushroom substrate to perlite at 3:1 exhibited the highest pile temperature and the best effect on reducing bulk density and moisture content. In addition, Fourier transform infrared spectra showed that perlite promotes the degradation of organic matter during the composting process, and the germination index showed that the compost from all treatments was safe for agricultural application. When the mass ratios of spent mushroom substrate and perlite at 3:1 and 2:2 were chosen as bulking agents, the sewage sludge compost product could be used to produce plant cultivation substrate, and economic benefits could be obtained from sewage sludge composting according to comprehensive cost analysis.

Volatile organic compounds (VOCs) are the major components of the odor emitted from sewage sludge composting plants and are generally associated with odorous nuisances and health risks. However, few studies have considered the potential ozone generation caused by VOCs emitted from sewage sludge composting plants. This study investigated the VOC emissions from a full-scale composting plant. Five major treatment units of the composting plant were chosen as the monitoring locations, including the dewatered room, dewatered sludge, blender room, fermentation workshop, and product units. The fermentation workshop units displayed the highest concentration of VOC emissions at 2595.7 ± 1367.3 μg.m−3, followed by the blender room, product, dewatered sludge, and dewatered room units, whose emissions ranged from 142.2 ± 86.8 μg.m−3 to 2107.6 ± 1045.6 μg.m−3. The detected VOC families included oxygenated compounds, alkanes, alkenes, sulfide compounds, halogenated compounds, and aromatic compounds. Oxygenated compounds, particularly acetone, were the most abundant compounds in all samples. Principal component analysis revealed that the dewatered room and dewatered sludge units clustered closely, as indicated by their similar component emissions. The product units differed from the other sampling units, as their typical compounds were methanethiol, styrene, carbon disulfide, and hexane, all of which were the products of the latter stages of composting. Among the treatment units, the fermentation workshop units had the highest propylene equivalent (propy-equiv) concentration. Dimethyl disulfide and limonene were the major contributors. Limonene had the highest propy-equiv concentration, which contributed to the increased atmospheric reactivity and ozone formation potential in the surrounding air. To control the secondary environmental pollution caused by the VOC emissions during sewage sludge composting, the emission of limonene and dimethyl disulfide must be controlled from the blender room and fermentation workshop units.

Composting has been globally applied as an effective and cost-efficient process to manage and reuse sewage sludge. In the present study, four different phosphates as well as a mixture of ferrous sulfate and monopotassium phosphate were used in sewage sludge composting. The results showed that these phosphate amendments promoted an increase in temperature and the degradation of organic matter as well as reduction on nitrogen loss during 18 days of composting. In addition, ferrous sulfate and phosphate had a synergistic effect on reducing nitrogen loss. The contents of total phosphorus and available phosphorus in the compost with addition of 1% phosphate were 40.9% and 66.1% higher than the compost with control treatment. Using the BCR (Community Bureau of Reference) sequential extraction procedure, the addition of calcium magnesium phosphate significantly reduced the mobility factor of Cd, Zn and Cu by 24.2%, 1.7% and 18.8%, respectively. The mobility factors of Pb were increased in all samples, but the monopotassium phosphate treated sample exhibited the greatest Pb passivation ability with the lowest mobility factor increase (1.8%) among all treatments. The X-ray diffraction patterns of compost samples indicated that the passivation mechanism of Cu and Zn may be the forming CuFeS2 and ZnCu(P2O7) crystals during sewage sludge composting. The germination index showed that the compost of all treatments was safe for agricultural application; the germination index of the calcium magnesium phosphate treatment was 99.9 ± 11.8%, which was the highest among all treatments.

Composting is a major sludge-treatment method and bulking agents are very important in sludge composting. In this study, ceramsite and activated alumina balls were chosen as recyclable bulking agents for sludge composting. Variations in the temperature, pH, electrical conductivity, organic matter, dissolved organic carbon, moisture content, and heavy metals were detected during composting with different bulking-agent treatments as well as differences in the germination index values. The results showed that both bulking agents could ensure the maturity of the compost; further, ceramsite treatment resulted in the best water removal efficiency. According to the sequential extraction procedure, both ceramsite and activated alumina balls could stabilize Cd but they also increased the mobility of Zn. After comparing the effects of different particle sizes of ceramsite on composting, 20 mm was determined to be the most optimal value. Additionally, the recovery rates of ceramsite and activated alumina balls were 96.9% and 99.9%, respectively.

Anaerobic digestion and incineration are widely used sewage sludge (SS) treatment and disposal approaches to recovering energy from SS, but it is difficult to select a suitable technical process from the various technologies. In this study, life-cycle assessments were adopted to compare the energy- and greenhouse gas- (GHG) emission footprints of two sludge-to-energy systems. One system uses a combination of AD with incineration (the AI system), whereas the other was simplified by direct incineration (the DI system). Comparison between three SS feedstocks (VS/TS: 57.61 -73.1 ds.%) revealed that the AI system consistently outperformed the DI system. The results of sensitivity analyses showed that the energy and GHG emission performances were mainly affected by VS content of the SS, AD conversion efficiency, and the energy consumption of sludge drying. Furthermore, the energy and GHG emission credit of the two systems increased remarkably with the increase in the VS content of the SS. For the high-organic-content sludge (VS/TS: 55%–80%), the energy and GHG emission credit of the AI system increase with the increase of AD conversion efficiency. However, for the low organic content sludge (VS/TS: 30%–55%), it has the opposite effect. In terms of energy efficiency and GHG performance, the AI system is a good choice for the treatment of high-organic-content sludge (VS/TS>55%), but DI shows superiority over AI when dealing with low organic content sludge (VS/TS

BACKGROUND: DNA methylation plays a vital role in modulating genomic function and warrants evaluation as a biomarker for the diagnosis and treatment of lung squamous cell carcinoma (LUSC). OBJECTIVE: In this study, we aimed to identify effective potential biomarkers for predicting prognosis and drug sensitivity in LUSC. METHODS: A univariate Cox proportional hazards regression analysis, a random survival forests-variable hunting (RSFVH) algorithm, and a multivariate Cox regression analysis were adopted to analyze the methylation profile of patients with LUSC included in public databases: The Cancer Genome Atlas (TCGA), and the Gene Expression Omnibus (GEO). RESULTS: A methylated region consisting of 3 sites (cg06675147, cg07064331, cg20429172) was selected. Patients were divided into a high-risk group and a low-risk group in the training dataset. High-risk patients had shorter overall survival (OS) (hazard ratio [HR]: 2.72, 95% confidence interval [CI]: 1.82–4.07, P< 0.001) compared with low-risk patients. The accuracy of the prognostic signature was validated in the test and validation cohorts (TCGA, n= 94; GSE56044, n= 23). Gene set variation analysis (GSVA) showed that activity in the cell cycle/mitotic, ERBB, and ERK/MAPK pathways was higher in the high-risk compared with the low-risk group, which may lead to differences in OS.Interestingly, we observed that patients in the high-risk group were more sensitive to gemcitabine and docetaxel than the low-risk group, which is consistent with results of the GSVA. CONCLUSION: We report novel methylation sites that could be used as powerful tools for predicting risk factors for poorer survival in patients with LUSC.

As an efficient and cost-effective biological treatment method for sewage sludge, composting has been widely used worldwide. To passivate heavy metals and enhance the nutrient content in compost, in the present study, phosphate rock, calcium magnesium phosphate, and monopotassium phosphate were added to the composting substrate. According to the Community Bureau of Reference sequential extraction procedure, phosphate rock and monopotassium phosphate amendments exhibit a good passivation effect on Cd and Pb. The X-ray diffraction patterns proved the formation of Pb3(PO4)2 and Cd5(PO4)2SiO4 crystals, and X-ray absorption near-edge structure spectroscopy illustrated the change in P speciation after phosphate amendment. Furthermore, phosphate amendment increased the contents of total P and available P, and it reduced the loss of N during sewage sludge composting. The germination index showed that the target phosphate amendments in sewage sludge compost had no negative effects on seed germination, and this method has great potential to be used as a soil amendment.

In order to obtain deformation parameters in each block of Sichuan-Yunnan Region (SYG) in China by stages and establish a dynamic model about the variation of the strain rate fields and the surface expansion in this area, we taken the Global Positioning System (GPS) sites velocity in the region as constrained condition and taken advantage of the block strain calculation model based on spherical surface. We also analyzed the deformation of the active blocks in the whole SYG before and after the Wenchuan earthquake, and analyzed the deformation of active blocks near the epicenter of the Wenchuan earthquake in detail. The results show that, (1) Under the effects of the carving from India plate and the crimping from the potential energy of Tibetan Plateau for a long time, there is a certain periodicity in crustal deformation in SYG. And the period change and the earthquake occurrence have a good agreement. (2) The differences in GPS velocity fields relative Eurasian reference frame shows that the Wenchuan earthquake and the Ya'an earthquake mainly affect the crustal movement in the central and southern part of SYG, and the average velocity difference is about 4–8 mm/a for the Wenchuan earthquake and 2–4 mm/a for the Ya'an earthquake. (3) For the Wenchuan earthquake, the average strain changed from 10 to 20 nanostrian/a before earthquake to 40–50 nanostrian/a after the earthquake, but before and after the Ya’an earthquake, the strain value increased from about 15 nanostrian/a to about 30 nanostrian/a. (4) The Wenchuan earthquake has changed the strain parameter of each active block more or less. Especially, the Longmen block and Chengdu block near the epicenter. The research provides fundamental material for the study of the dynamic mechanism of the push extrusion from the north-east of the India plate and the crimp from Qinghai Tibet Plateau, and it also provides support for the study of crustal stress variation and earthquake prediction in Sichuan Yunnan region.

In order to develop an efficient and environmental-friendly alternative for enhancing dewatering performance of waste activated sludge (WAS), the sludge derived biochar loaded with MnFe2O4 (MnFe2O4@SBC) was firstly prepared for catalyzing ozonation of sludge. The optimal condition was determined to be pH = 6, O3 dosage = 60 mg/g VS and MnFe2O4@SBC dosage = 600 mg/g VS, under which the capillary suction time (CST) and specific resistance to filtration (SRF) of WAS declined from 98.3 ± 1.0 s and 1.1 ± 0.03 × 1014 m/kg to 18.3 ± 0.8 s and 0.32 ± 0.03 × 1014 m/kg, respectively. The water content (Wc wt.%) of sludge cake declined from 87.1 ± 0.98% to 68.1 ± 0.87%. The mechanism for enhanced dewatering performance of WAS by MnFe2O4@SBC was systematically clarified. Firstly, the circulation of valence states for Fe and Mn on the surface of MnFe2O4@SBC was found promoting the conversion of O3 into highly active free radicals and the generation of hydroxyl radicals (·OH). Secondly, the density functional theory (DFT) calculation firstly manifested that O3 molecules were easier to be activated and dissociated into ·OH groups on the surface of MnFe2O4 phase. With the above promotion of ·OH generation, the inner part of sludge flocs especially the protein in extra-cellular polymers (ECPS) was destructed strongly, with significant release of bound water and the decrease in water bound energy. The organic biopolymers with negative charges were diminished followed by the increased zeta potential and enlarged particle size, resulting in the enhanced dewatering performance of WAS. This study illustrated the rationality and validity of the new strategy for enhanced sludge dewatering in both practice and theory, shedding light on the further development of sludge dewatering technology.

Composting is an effective method for treating sewage sludge. The aim of this work was to study preservation of nitrogen and sulfur and passivation of heavy metals during sewage sludge composting with KH

Volatile sulfur compounds (VSCs) are the main toxic components generated simultaneously with biogas in anaerobic digestion (AD) of sludge. The differences of chemical and biological processes involved in the VSCs conversion between conventional AD and thermal hydrolysis pretreated high solid AD (THP-HSAD), widely applied in recent years, have yet to be fully elucidated. This study evaluated the effect of solid content, initial pH, and thermal hydrolysis on the VSCs conversion in AD. This study had evidenced that neither the solids content nor the pH adjustment affects the VSCs conversion. It was found that free ammonia nitrogen concentration, which increased (>500 mg/L) in HSAD, directly inhibited the enzymatic activity of cysteine lyase (R2 = 0.87, P

Composting is an effective method for treating sewage sludge. The aim of this work was to study preservation of nitrogen and sulfur and passivation of heavy metals during sewage sludge composting with KH2PO4 and FeSO4. The results show the loss rate of N decreased by 27.5% while that of S was increased by 32.1% compared with the control treatment during composting when KH2PO4 and FeSO4 were added. X-ray absorption near-edge structure spectra show that S was converted to a highly oxidizable state during sewage sludge composting with added KH2PO4. The mobility factors of Cu, Zn, and Pb after composting were found to decrease by 13.6%, 21.6%, and 3.8%, respectively, compared with those before composting when KH2PO4 was added. Adding these two materials to Cu and Zn inhibits Zn3(PO4)2(H2O)4 and Cu5(PO4)2(OH)4 from transforming into more mobile forms, while adding these materials to Pb promotes Pb3(PO4)2 formation.

Oxygen is an important parameter for organic-waste composting, and continuous control of the oxygen in a composting pile may be beneficial. The oxygen consumption rate can be used to measure the degree of biological oxidation and decomposition of organic matter. However, without having a real-time online device to monitor oxygen levels in the composting pile, the adjustment and optimization of the composting process cannot be directly implemented. In the present study, we researched and developed such a system, and then tested its stability, reliability, and characteristics. The test results showed that the equipment was accurate and stable, and produced good responses with good repeatability. The equilibrium time required to detect oxygen concentration in the composting pile was 50 s, and the response time for oxygen detection was less than 2 s. The equipment could monitor oxygen concentration online and in real time to optimize the aeration strategy for the compost depending on the concentration indicated by the oxygen-measuring equipment.

The solubilization of 2,4,6-trichlorophenol (2,4,6-TCP) was studied in the presence of four different surfactants, namely sodium deoxycholate (NaDC), sodium cholate (NaC), sodium lauryl sulfate (SDS) and beta-cyclodextrin (beta-CD). The solubility of 2,4,6-TCP was enhanced a maximum of 72 times especially by NaDC at pH 7.5. In addition, other than great solubilization capacities, NaDC and NaC have the advantages of high biodegradability and biocompatibility as biosurfactants. The adsorption behaviors of 2,4,6-TCP on the surface of soil in the presence of these solubilizers were examined. The results showed that the adsorption isotherms for all studied surfactants matched the Henry adsorption isotherm well. The adsorption mechanisms were explored and the adsorption behaviors of 2,4,6-TCP were affected by different micelle forms of the surfactants based on their critical micelle concentration (CMC). The adsorption process was demonstrated by a redistribution procedure between surfactants in solution and surfactants adsorbed onto the soil surface. In particular, the adsorption of 2,4,6-TCP was almost zero when NaC concentration was above CMC2.The results of our study have important implications for soil remediation and non-point source pollution control. (C) 2013 Elsevier B.V. All rights reserved.

Catalase, a kind of redox enzyme and generally recognized as an efficient agent for protecting cells against hydrogen peroxide (H2O2)-induced cytotoxicity. The immobilization of catalase was accomplished by depositing the positively charged chitosan and the negatively charged catalase on electrospun cellulose nanofibrous mats through electrospining and layer-by-layer (LBL) techniques. The morphology obtained from Field emission scanning electron microscopy (FE-SEM) indicated that more orderly arranged three-dimension (3D) structure and roughness formed with increasing the number of coating bilayers. Besides, the enzyme-immobilized nanofibrous mats were found with high enzyme loading and activity, moreover, X-ray photoelectron spectroscopy (XPS) results further demonstrated the successful immobilization of chitosan and catalase on cellulose nanofibers support. Furthermore, we evaluated the cytotoxicity induced by hydrogen peroxide in the Human umbilical vascular endothelial cells with or without pretreatment of nanofibrous mats by MTT assay, LDH activity and Flow cytometric evaluation, and confirmed the pronounced hydrogen peroxide-induced toxicity, but pretreatment of immobilized catalase reduced the cytotoxicity and protected cells against hydrogen peroxide-induced cytotoxic effects which were further demonstrated by scanning electron microscopy (SEM) and Transmission Electron Microscopy (TEM) images. The data pointed toward a role of catalase-immobilized nanofibrous mats in protecting cells against hydrogen peroxide-induced cellular damage and their potential application in biomedical field.

Surface soils from the outskirts of Beijing were analyzed for 16 priority polycyclic aromatic hydrocarbons (PAHs) using gas chromatography and mass spectrometry (GC-MS). The distribution map of total PAHs content was obtained as a contour plot. The concentration range of 16 PAHs varied by over two orders of magnitude from 0.016 mu g g(-1) in rural to 3.884 mu g g(-1) in suburban soils with the relatively standard deviation of 70.5%, showing large differences in the extent of PAHs pollution at the various sampling sites. It was notable that the concentration of BaP was 0.005-0.270 mu g g(-1) with a mean of 0.055 mu g g(-1). In general, the distribution of PAHs centered on the high molecular weight PAHs known to be carcinogenic. The 4-6 ring PAHs represented about 66% in rural samples and 70% in suburban soils of the total PAHs found. There was relatively good relationship among most of the individual PAHs and the compounds of Pyr, BaA, Flu, BbF, BaP, Chr and Ph gave strong correlation (r > 0.8) with the sum of PAHs. The selected marked compounds, a principal component analysis (PCA) and special PAHs compound ratios (Ph/An vs Flu/Pyr; Sigma COMB/Sigma EPA - PAHs) suggest the pyrogenic origins, especially traffic exhausts, are the dominant sources of PAHs in Beijing outskirts soils. (c) 2004 Elsevier Ltd. All rights reserved.

In this study, albumin egg (AE) induced layered rectorite (REC) to exfoliate by electrostatic forces between the molecular chains of AE and the interlayer of REC, which was confirmed by small angle X-ray diffraction. The composite nanofibrous mats with the exfoliated layered rectorite were successfully fabricated via electrospinning poly(vinyl alcohol) (PVA)/AE/REC solutions with different mass ratios. The morphology of the nanofibrous membranes was examined by field emission scanning electron microscopy. Energy-dispersive X-ray spectroscopy and Fourier transform infrared spectra showed the existence of REC in the composite nanofibrous mats. Besides, the wide angle X-ray diffraction and Fourier transform infrared spectra results demonstrated the crystalline structure of PVA was changed by formic acid. The differential scanning calorimetry and the thermo-gravimetric analysis results suggested that REC could slightly improve the thermal stability of the composite nanofibrous mats. MTT assay showed the nanofibrous mats were nontoxic and beneficial to the proliferation of L929 cells.