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Evidence has demonstrated that the gut microbiota, which consists of probiotics and pathogenic microorganisms, is involved in the initiation of ulcerative colitis (UC) via the dysregulation of intestinal microflora and normal immune interactions, which ultimately leads to intestinal mucosal dysfunction. Irisin is released from muscle cells and displays anti-inflammatory effects; however, the mechanisms underlying irisin-mediated anti-inflammatory effects in UC have not been previously reported. In the present study, mice were divided into the following four groups: i) Control; ii) irisin; iii) dextran sulfate sodium (DSS) salt; and iv) DSS + irisin. Subsequently, the effects of irisin were investigated by observing alterations in intestinal microbes. Irisin significantly reduced the degree of inflammation in UC by reversing alterations to the macroscopic score, histological score, number of CD64+ cells and inflammatory cytokine alterations (P<0.05). Analysis of the microbial diversity in the stools of mice with active UC indicated that the five bacteria that displayed the greatest alterations in relative abundance were Alloprevotella, Bacteroides, Lachnospiraceae-UCG-001, Prebotellaceae-UCG-001 and Rikenellaceae-RCB-gut-group. Furthermore, Bactoroides were positively correlated with the histopathological score (P=0.001; R=0.977) and interleukin (IL)-23 levels (P=0.008; R=0.924). Alloprevotella (P=0.001; R=-0.943), Lachnospiraceae-UCG-001 (P=0.000; R=-0.973) and Rikenollaceae-RC8-gut-group (P=0.001; R=-0.971) were negatively correlated with the histopathological score. Furthermore, Lachnospiraceae-UCG-001 (P=0.01; R=-0.873) and Rikenollaceae-RC8-gut-group (P=0.049; R=-0.814) were negatively correlated with IL-23 levels. In summary, the results of the present study suggested that irisin improved inflammation in a UC mouse model potentially via altering the gut microbiota. [ABSTRACT FROM AUTHOR]

To investigate the potential application of nitrocellulose membrane (NCM) in water treatment, this study examined the photolysis of p -nitrophenol, with NCM as the source of reactive oxygen species. Effects of solution pH, light conditions, and water dissolved substances on p -nitrophenol photolysis were investigated, and possible mechanisms were discussed. The results demonstrated that the quantum yield for hydroxyl radicals from the NCM was 1.30×10 -4 , which is approximately 1.86 times higher than that from TiO 2 . The photolysis rate of p -nitrophenol in the presence of NCM was 0.0055 min -1 , which is much higher than that in pure water (9.52×10 -4 min -1 ). This promotion was mainly caused by photo-induced generation of ·OH on NCM surface under light, in which UVA plays an important role in photolysis. The photolysis rate of p -nitrophenol increased with the increase of light intensity and membrane area. Acidic solution (pH=2.0) was preferred for the degradation of p -nitrophenol, with a photolysis rate of 0.0165 min -1 ; the corresponding degradation of p -nitrophenol exceeded 90% in 120 min. The effects of dissolved substances on photolysis were significantly different. NO 3 - promoted photolysis by generation of ·OH, and dissolved organic matter decreased photolysis through light attenuation. The intermediate products of gas chromatography-mass spectrometry analysis mainly included phenol, hydroquinone, malonic acid, and oxalic acid, and the possible photolysis pathway was given accordingly.

Odor pollution of landfill site is a serious problem accompanied with the urbanization process that influences city life. Generally, odor emission points in landfill boundary are detected by experience, but the pollution intensity, distribution and variation in the scope of landfill boundary are difficulty to describe. In this research, odor emission points were disclosed with equal odor concentration curves that were delineated using electric nose and GPS instrument. The leakage of landfill gas and exhaust emission from biogas incineration torch was the main cause of the odor pollution in landfill area. Gas production evaluation suggested that the improvement of landfill gas consumption is the key point to control the odor pollution at the landfill site.

The odor pollution of landfill is one of seriously pollutions in city ambient area. Main pollution points in the landfill area have been detected by preliminary research. For a particular purpose to recover the materials changing in odor dispersion process and to find out odor indication material, GC-MS method was used to detect materials in the different site at down wind direction. Then, similarity coefficient of VOCs (volatile organic compounds) composition between every two site were calculated and compared to look for changing regular of odor pollution in diffusion process. The odor pollution indictor material has be found in the materials that appeared in down wind direction of operation area and compared its' olfaction threshold. The results show that: there have 19 types of common materials in the landfill area, including monoaromatics, alkanes and halogenated compounds; Materials in the air of operation area site has marked influence on down windward direction air of landfill, and m-xlyene has been selected as odor pollution indictor of landfill air by this research.