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Supplementary results about consistence between metagenomic data and 16S rRNA data. (DOCX 29 kb)

Alpha-diversities of bacterial OTUs and DOM molecules in the tested soil samples across four typical paddy fields. A: Boxplots of alpha-diversities of bacterial OTUs using four indices: Chao1, observed species, Shannon and PD whole tree. B: Boxplots of alpha-diversities of DOM molecules using three indices: Chao1, observed species, and Shannon. We randomly subsampled 43,000 sequences and 9000 per sample ten times to correct for differences in sequencing depth for bacterial OTUs and DOM molecules. In the boxplots, the symbols indicate the following: box, lower and upper quartiles; horizontal line, median value; whiskers, lower and upper inner fence. The circle above or below the box plots indicates outliers. Differences among the four regions were tested using non-parametric Kruskal–Wallis test (P 0; N ≥ 0; H > 0; O ≥ 0; 1 ≥ P ≥ 0; 1 ≥ S ≥ 0; H ≥ C/3; H ≤ 2C + N + P + 2; 2|(N + H + P) = 0; N ≤ C; O + S ≤ C + 2 N + 3P; O + S ≥ P. Functional group relationships or “chemical building block” used in elemental formula assignment: CH4 - O (0.036385 Da), C2H2 (26.015650 Da), C2H4 (28.031300 Da), CH2 (14.015650 Da), H2 (2.015650 Da), H2O (18.010565 Da), O (15.994915 Da), CO2 (43.989830 Da), NH (15.010899 Da), S (31.972071 Da). (DOCX 1840 kb)

Global warming poses a great threat to wetland ecological stability and water quality improvement. In this paper, we sampled six types of wetlands representing different kinds of land utilisation around the TaiHu Lake Basin in southeast China. An outdoor computerized microcosm was set up in May 2008 to simulate climate scenarios of ambient temperature (control) and a warmed ambient temperature (+5 °C) using a novel minute-scale daily and seasonal temperature manipulation technology. The 18-month incubation indicated that warming impaired the ecological sink of sediment (fixing P from porewater) while strengthening the role of the ecological source, moreover, the rate of P release from sediment into porewater (19–113% for total phosphorus) was much stronger than from top sediment into overlying water. Warming enhanced the activity of neutral and alkaline phosphatases for P-deficient wetland sediments and neutral phosphatases for P-rich sediments, at the 14th month of incubation. A significant increase in total phospholipid fatty acids (PLFAs) occurred under warming in sediments with relatively low levels of PLFAs, but bacterial abundance in the sediment biomass tended to decrease (18%) along with an increase (4·5%) of the fungi-to-bacteria ratio. The variations of carbon consumption and availability indicated by measured dissolved organic carbon in sediment may have contributed to P release from sediments to water. Copyright © 2011 John Wiley & Sons, Ltd.

The South Lake Taihu region is increasingly threatened by water eutrophication,so it is important to understand phosphorus status in sediments and water of the riparian wetlands in this region and develop sound technologies for optimizing wetlands'ecological values.29 typical sampling sites in this region were chosen for the investigation,and the sites located at Hangzhou West Lake,Deqing Xiazhuohu Wetland,and Changxing Baoyanghe River were selected for static column simulation experiments and steady-flow flume simulation experiments.According to the investigation,total phosphorus(TP)and NaHCO_3 (pH=8.5)extractable phosphorus(Olsen-P)in sediments of the region reached 0.169-1.200g/kg and 7.08-67.08mg/kg,respecially, and the adsorption capacity(Q_(max))of sediments varied from 269.5 to 824.Smg/kg.NaOH+EDTA extractable phosphorus (NaOH+EDTA-P)constituted 52.0%±11.6% of TP,while Olsen-P was increased as organic phosphorus accumulated.TP in overlying water was 0.036-0.944mg/L,while dissolved reactive phosphorus(DRP)was relatively and 34.5% of the total sites was below detective limits.Total particle phosphorus(TPP)contributed 70.9%±13.2% of TP in water samples.There was no significant relationship between TP,DRP in overlying water and TP,NaOH+EDTA-P,Olsen-P in sediments,implying that phosphorus status in sediments was not the only factor restricting phosphorus in overlying water.In the static column simulation experiments,DRP in overlying water decreased slowly at the beginning,then decreased fastly later on.A quasi U-pattern curve was found in the steady-flow flume simulation experiments,i.e.DRP in the overlying water decreased at first and then turned to be increasing.It indicated that the role of the sediments might be changed from phosphorus"sink"to"source"when high phosphorus water flow over a wetland in rain season.It was also proved in the simulation experiments that organic matter accelerated the adsorption rates of phosphorus by sediments.

The purpose of this study was to observe the effects of olfactory ensheathing cell conditioned medium (OECCM) on damaged astrocytes after exposure to H2O2 in vitro. OECCM was used to treat astrocytes after injury, which was induced by exposure to 500 μmol/L H2O2 for 20 min. The cell morphology was then observed under a light microscope, cell viability assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, cell ultrastructure observed with transmission electron microscopy (TEM), and apoptosis assessed by Annexin V staining followed by cytometry and Western blot. H2O2 induced severe damage to astrocytes as evidenced by decreased cell number, pathological changes in cell morphology, and significantly elevated cell apoptosis. Cells incubated with OECCM displayed significantly improved cell viability and decreased cell apoptotic rate. Under TEM, H2O2-treated cells showed partially broken plasma membranes, swollen rough endoplasmic reticula, visible vacuoles, and swollen or deformed mitochondria with ruptured cristae. Incubation with OECCM significantly ameliorated these pathological changes in astrocytes. These results suggest that OECCM may protect astrocytes from oxidative damage by promoting cell survival while reducing apoptosis of the damaged cells.

With the rapid development of automotive industry,the requirements for engine performance has become increasingly higher and higher,such as dynamic performance,environmental performance,fuel economy performance and so on.Obviously,using lighter aluminum engine has become the future of the automobile industry.When start or stop the engine,the engine generates drastic temperature field that will make parts of the engine components into the plastic deformation zone.If the engine components continue like this,extremely high thermal strain will cause the thermal fatigue failure of aluminum alloy for automotive engine.Thermal fatigue is a more serious form of material fatigue failure.The thermal fatigue is prevalent in many important engine castings,such as cylinder body,cylinder head,piston and so on.Therefore,study on thermal fatigue properties of multivariate Al-Si-Cu cast alloy has the most important significance.Based on this thermal fatigue behaviors of multivariate Al-7.5Si-4Cu alloys under different heat treatment were investigated in the temperature ranges of room temperature to 350℃.The thermal fatigue cracks of the tested specimens were observed using OM and SEM.The results demonstrate that thermal fatigue properties of the alloy after T6 heat treatment is better than the alloy after cast-quenching+aging heat treatment and the cast alloy.Reasonable heat treatment process can improve the strength,the plasticity and the thermal fatigue property of multivariate Al-7.5Si-4Cu alloy,including reduce the rate of crack propagation. The main reason of crack initiation is oxidative microstructure induced by thermal stress.Fatigue crack expands along the grain boundary by passivation-sharpen of crack tip in the early.In the late,fatigue crack expands with both intergranular way and transgranular way by passivation-sharpen of crack tip and siamesed holes on front edge of crack tip.The Si phases can affect fatigue crack propagation.When the angle between the fatigue crack propagation and the short axis of the Si phase is more than 60°,fatigue crack expands as"bypass-wall expansion".When the angle between the fatigue crack propagation and the long axis of the Si phase is more than 60°,fatigue crack expands as"through-wall expansion".Oxidation behavior effects significantly at the crack initiation period.After T6 heat treatment,the antioxidant property of multivariate Al-7.5Si-4Cu alloy is the best.Oxidation kinetics curves of multivariate Al-7.5Si-4Cu alloy under the different heat treatment are all logarithmic relationship.