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41.Randomised clinical trial: the effectiveness of Gaviscon Advance vs non-alginate antacid in suppression of acid pocket and post-prandial reflux in obese individuals after late-night supper

Author:Deraman, MA;Hafidz, MIA;Lawenko, RM;Ma, ZF;Wong, MS;Coyle, C;Lee, YY


Abstract:Background Late-night supper increases the risk of postprandial reflux from the acid pocket especially in obesity. An alginate-based, raft-forming medication may be useful for obese patients with GERD. Aims To compare the efficacy of Gaviscon Advance (Reckitt Benckiser, UK) and a non-alginate antacid in post-supper suppression of the acid pocket and post-prandial reflux among obese participants. Methods Participants underwent 48 h wireless and probe-based pH-metry recording of the acid pocket and lower oesophagus, respectively, and were randomised to single post-supper (10 pm) dose of either Gaviscon Advance or a non-alginate antacid on the second night. Primary outcomes were suppression of median pH of acid pocket and lower oesophagus, measured every 10-minutes post-supper for 1 h. Secondary outcomes were suppression of %% time pH < 4 at lower oesophagus and improvement in frequency and visual analogue score (VAS) of regurgitation. Results Of the 81 screened participants, 55 were excluded and 26 (mean age 33.5 years, males 77.8%% and BMI 32.8 kg/m(2)) were randomised to Gaviscon Advance (n = 13) or antacid (n = 13). Median pH of the acid pocket but not the lower oesophagus was suppressed with Gaviscon Advance vs antacid (all P < 0.04) Gaviscon Advance but not antacid significantly reduced in %% time pH < 4, symptom frequency and VAS on day 2 vs day 1 (all P < 0.05). Conclusions Among obese individuals, Gaviscon Advance is was superior to a non-alginate antacid in post-supper suppression of the acid pocket. (Clinical trial registration unique identifier: NCT03516188).

42.In Situ Growth of NiO@SnO2 Hierarchical Nanostructures for High Performance H2S Sensing

Author:Liu, L;Wang, YY;Dai, YB;Li, GH;Wang, SQ;Li, T;Zhang, T;Qin, SJ


Abstract:Heterostructured metal oxides with large specific surface area are crucial for constructing gas sensors with high performance. However, using slurry-coating and screen-printing methods to fabricate gas sensors cannot result in high uniformity and reproducibility of the sensors. Here, NiO nanowalls decorated by SnO2 nanoneedles (NiO@SnO2) were in situ grown on ceramic microchips via a chemical bath deposition method to detect H2S instead of print-coating and slurry-coating methods. The morphologies and compositions of the NiO@SnO2 hierarchical nanostructures (HNSs) were well tuned by varying the growth time of the NiO@SnO2 HNSs to optimize the sensing performance. The response of the NiO@SnO2 HNSs (2 h) to 1 ppm of H2S was over 23-fold higher than that of the pure NiO nanowalls and 17-fold higher than that of the pure SnO2 nanosheets. This dramatic enhancement is attributed to the large surface area of the NiO@SnO2 HNSs and the p-n heterojunction at the heterointerface of SnO2 and NiO. The variation in the depletion layers (W-SnO2 and W-NiO) at the heterointerface of SnO2 and NiO greatly depends on the properties of the target gases (e.g., electron-withdrawing property (NO2) or electron-donating property (H2S)).

43.The embryonic toxicity evaluation of deoxynivalenol (DON) by murine embryonic stem cell test and human embryonic stem cell test models

Author:Fang, HQ;Zhi, Y;Yu, Z;Lynch, RA;Jia, XD

Source:FOOD CONTROL,2018,Vol.86

Abstract:Deoxynivalenol (DON) is a group B trichothecene and a common contaminant of food crops worldwide. DON is known to cause a spectrum of diseases in animals and humans such as vomiting and gastroenteritis and has been shown to cross the human placental barrier: therefore, dietary exposure during pregnancy could lead to exposure of the fetus. Since the mechanism of DON toxicity action has not been thoroughly elucidated, further evaluation of the underlying mechanisms of DON's embryotoxicity is needed. This is especially important for developing exposure guidance recommendations, especially those targeted towards pregnant women. In the present study, murine embryonic stem cell test (mEST) and human embryonic stem cell test (hEST) models were developed according to protocols of the European Centre for the Validation of Alternative Methods (ECVAM). Different concentrations of DON were administered to mouse embryonic stem cells D3 (mESC-D3), mouse Balbic-3T3 (3T3) embryo fibroblast cells, and human embryonic stem cells H9 (hESC-H9) for 10 days to detect the 50%% inhibitory proliferation concentration (1050) of mESC-D3 cells, 313 cells, and hESC-H9 cells with DON. Differentiation of ESCs was initiated by embryoid body (EBs) formation. EBs were exposed to different concentrations of DON for 10 days. The expression of cardiomyocyte differentiation gene alpha-myosin heavy chain (alpha-MHC) was detected by real-time PCR and the 50%% inhibition of cardiomyocyte differentiation (ID50) was determined. Based on the values of IC50 and ID50, functions I, II, and III were calculated by three linear discriminant functions in the EST model and the embryotoxicity of DON was described by comparing the three functions. Results of the three endpoints of DON in murine EST were 0.141 mu g/ml (IC50 3T3), 0.085 mu g/ml (IC50 D3), and 0.110 mu g/ml (ID50 D3). The function I (-34.43), function II (-18.62), and function III (1.98) were calculated for DON by them EST model. The three endpoints of DON in hEST were 0.13 mu g/ml (IC50 313), 0.11 mu g/ml (IC50 H9), and 0.078 mu g/ml (ID50). Function I (-25.97), function II (-13.18), and function III (-0.12) were calculated based on IC50 and ID50. Since function III > function II > function I, according to the EST criteria, DON was determined to have strong embryo toxicity both by mEST and hEST. Moreover, the hEST model, which excluded species differences, is suggested to be a more accurate and reliable method for the evaluation of chemical embryotoxicity. (C) 2017 Elsevier Ltd. All rights reserved.

44.Mild-to-moderate iodine deficiency in a sample of pregnant women and salt iodine concentration from Zhejiang province, China

Author:Yu, ZL;Zheng, CJ;Zheng, WF;Wan, ZX;Bu, YJ;Zhang, GF;Ding, SB;Wang, EH;Zhai, DS;Ma, ZF


Abstract:Since 2011, Zhejiang province has eliminated iodine deficiency disorders (IDD) in its populations. Following this achievement, a new revised iodine concentration in iodised salt was implemented in Zhejiang in 2012. However, the re-emergence of iodine deficiency has been reported in pregnant women. Therefore, the aim of this study was to assess household salt iodine concentration and iodine status of pregnant women in Zhejiang province, China. We conducted a cross-sectional study between April 2018 and August 2018 in Quzhou, Zhejiang province. Pregnant women aged >= 18 years who did not have a history of thyroid disease were recruited into the study. They were asked to complete socio-demographic questionnaires including a food frequency questionnaire (FFQ). In addition, a spot urine sample and a household table salt sample were also provided by each participant. A total of 625 pregnant women agreed to participate. The overall median urinary iodine concentration (UIC) was 130 mu g/L, indicating mild-to-moderate iodine deficiency in pregnant women. The coverage of iodised salt was 85.2%%, and of these, the rate of adequately iodised salt was 98.1%%. In conclusion, our results confirmed the re-emergence of iodine deficiency in pregnant women as reported by other studies conducted in Zhejiang province. Therefore, urgent public health actions are needed to improve iodine status of pregnant women in order to prevent the adverse consequences of IDD on the neurodevelopment of foetus.

45.Driving force of condomless sex after online intervention among Chinese men who have sex with men

Author:Huang, WT;Wu, D;Pan, SW;Li, K;Ong, JJ;Fu, HY;Liu, CC;Mao, J;Tucker, JD;Tang, WM

Source:BMC PUBLIC HEALTH,2019,Vol.19

Abstract:Background: Condom use remains consistently low among Chinese men who have sex with men (MSM). This study aims to identify factors associated with condom use after online video intervention. Methods: This is a secondary data analysis of data collected from an online non-inferiority trial comparing the effectiveness of two condom use promotion video interventions among Chinese MSM. Participants from the two groups were combined since the effectiveness of two video interventions were shown to be non-inferior. Univariable and multivariable logistic regression were used to identify factors associated with condomless sex after the intervention during the follow-up interval. Results: Overall, 1173 participants were recruited at baseline and 791 (67.4%%) completed the three-month follow-up survey. 57.3%% (453/791) of the participants reported condomless sex after intervention in the three-month follow-up interval. MSM who have had sex under the influence of alcohol in the last 3 months (Odds Ratio(OR) = 1.90; 95%% CI: 1.22, 2.97; Adjusted OR(AOR) = 1.79; 95%% CI: 1.13, 2.83) and ever have had sex tourism (OR = 2.75; 95%% CI: 1.34, 5.63; AOR = 2.40; 95%% CI: 1.15, 5.07) at baseline were more likely to have condomless sex after intervention in the three-month follow-up period. MSM who had a higher level of community engagement in sexual health (OR = 0.54; 95%% CI: 0.35, 0.82; AOR = 0.49; 95%% CI: 0.32, 0.75 with substantial engagement) and who viewed additional condom promotion videos during the follow-up period by themselves (OR = 0.67; 95%% CI = 0.50, 0.89; AOR = 0.67; 95%% CI: 0.50, 0.91). were less likely to have condomless sex during the follow-up period. Conclusion: The intervention appeared to be effective among MSM who reported viewing additional condom promotion videos by themselves and more community engagement after the intervention. In MSM who reported risky sexual behaviors at baseline, the intervention appeared less effective. Tailored intervention videos that target particular subgroups, active in-person community engagement, and optimized intervention frequency should be considered in future sexual health interventions.

46.Microbial Organic Matter Utilization in High-Arctic Streams: Key Enzymatic Controls

Author:Pastor, A;Freixa, A;Skovsholt, LJ;Wu, NC;Romani, AM;Riis, T

Source:MICROBIAL ECOLOGY,2019,Vol.78

Abstract:In the Arctic, climate changes contribute to enhanced mobilization of organic matter in streams. Microbial extracellular enzymes are important mediators of stream organic matter processing, but limited information is available on enzyme processes in this remote area. Here, we studied the variability of microbial extracellular enzyme activity in high-Arctic fluvial biofilms. We evaluated 12 stream reaches in Northeast Greenland draining areas exhibiting different geomorphological features with contrasting contents of soil organic matter to cover a wide range of environmental conditions. We determined stream nitrogen, phosphorus, and dissolved organic carbon concentrations, quantified algal biomass and bacterial density, and characterized the extracellular enzyme activities involved in catalyzing the cleavage of a range of organic matter compounds (e.g., beta-glucosidase, phosphatase, beta-xylosidase, cellobiohydrolase, and phenol oxidase). We found significant differences in microbial organic matter utilization among the study streams draining contrasting geomorphological features, indicating a strong coupling between terrestrial and stream ecosystems. Phosphatase and phenol oxidase activities were higher in solifluction areas than in alluvial areas. Besides dissolved organic carbon, nitrogen availability was the main driver controlling enzyme activities in the high-Arctic, which suggests enhanced organic matter mineralization at increased nutrient availability. Overall, our study provides novel information on the controls of organic matter usage by high-Arctic stream biofilms, which is of high relevance due to the predicted increase of nutrient availability in high-Arctic streams in global climate change scenarios.

47.A copula-based model for air pollution portfolio risk and its efficient simulation

Author:Sak, H;Yang, GY;Li, BL;Li, WF


Abstract:This paper introduces a portfolio approach for quantifying pollution risk in the presence of PM concentration in cities. The model used is based on a copula dependence structure. For assessing model parameters, we analyze a limited data set of PM levels of Beijing, Tianjin, Chengde, Hengshui, and Xingtai. This process reveals a better fit for the t-copula dependence structure with generalized hyperbolic marginal distributions for the PM log-ratios of the cities. Furthermore, we show how to efficiently simulate risk measures clean-air-at-risk and conditional clean-air-at-risk using importance sampling and stratified importance sampling. Our numerical results show that clean-air-at-risk at 0.01 probability level reaches up to (initial PM concentrations of cities are assumed to be ) for the constructed sample portfolio, and that the proposed methods are much more efficient than a naive simulation for computing the exceeding probabilities and conditional excesses.

48.Water quality trends in New Zealand rivers: 1989-2009

Author:Ballantine, DJ;Davies-Colley, RJ


Abstract:Recent assessments of water quality in New Zealand have indicated declining trends, particularly in the 40 %% of the country's area under pasture. The most comprehensive long-term and consistent water quality dataset is the National Rivers Water Quality Network (NRWQN). Since 1989, monthly samples have been collected at 77 NRWQN sites on 35 major river systems that, together, drain about 50 %% of New Zealand's land area. Trend analysis of the NRWQN data shows increasing nutrient concentrations, particularly nitrogen (total nitrogen and nitrate), over 21 years (1989-2009). Total nitrogen and nitrate concentrations were increasing significantly over the first 11 years (1989-2000), but for the more recent 10-year period, only nitrate concentrations continued to increase sharply. Also, the increasing phosphorus trends over the first 11 years (1989-2000) levelled off over the later 10-year period (2000-2009). Conductivity has also increased over the 21 years (1989-2009). Visual clarity has increased over the full time period which may be the positive result of soil conservation measures and riparian fencing. NRWQN data shows that concentrations of nutrients increase, and visual clarity decreases (i.e. water quality declines), with increasing proportions of pastoral land in catchments. As such, the increasing nutrient trends may reflect increasing intensification of pastoral agriculture.

49.Enteral combined with parenteral nutrition improves clinical outcomes in patients with traumatic brain injury

Author:Li, XM;Yang, YF;Ma, ZF;Gao, S;Ning, Y;Zhao, L;He, ZY;Luo, XQ


Abstract:Objective: To investigate the effect of nutritional support on nutritional status and clinical outcomes of patients with traumatic brain injury (TBI). Methods: Sixty-one patients with TBI from the intensive care unit and neurosurgery of Xianyang Central Hospital from 2017 to 2019 were retrospectively included. General and clinical data of the study subjects were collected. The control group (n = 28) received parenteral nutrition alone, and the observation group (n = 33) received parenteral nutrition combined with enteral nutrition. The general conditions and biochemical indicators of both groups of patients were divided into two groups of <= 8 and >= 9 for stratified analysis to compare the nutritional support status and infection complications during hospitalization Occurrence, ICU length of stay, total length of stay, total cost of stay, and prognostic indicators of the patients were analyzed and compared. Results: There were no significant differences in biochemical indicators between both groups of patients when they were discharged. Among patients with GCS <= 8 points, the incidence of lung infection in the observer was significantly higher than that in the control group (P < 0.001), but the incidence of intracranial infection, stress ulcers, and diarrhea was not statistically different from that in the control group (P = 0.739). No significant differences were observed in hospitalization time and hospitalization costs between both groups (P = 0.306 and P = 0.079, respectively). The observation group was significantly better than the control group in GSC score and long-term quality of life score (P = 0.042 and P = 0.025, respectively). When GCS was >= 9 points, there was no statistical difference in the incidence of lung infections and intracranial infections between both groups of patients (P = 0.800 and P = 0.127, respectively). The observation group was significantly higher than the control group in terms of length of hospital stay, nasal feeding time and hospitalization costs (P < 0.001, P < 0.001 and P = 0.006, respectively). The observation group was significantly better than the control group in GSC score and long-term quality of life score (P = 0.001 and P = 0.015, respectively). There was no significant difference in the incidence of pulmonary infection and intracranial infection between both groups of patients (P = 0.800 and P = 0.127, respectively). Conclusion: Enteral nutrition combined with parenteral nutrition intervention has a positive effect on the clinical prognosis of TBI patients.

50.A new perspective on landscape impact in bee populations:Considering the bee gut microbiome

Author:Tang Min;Zou Yi;Su Qinzhi;Zhou Xin

Source:Biodiversity Science,2019,Vol.27

Abstract:Pollinator bees are providers of an important ecosystem service,and their survival relies completely on the landscape.Now with the landscape dominated by agriculture,bee diversity has been significantly reduced.Studies suggest that bee populations decline as agricultural land-use increases due to increased exposure to detrimental pesticides.Further,the protein content of pollen is highly important for the growth and development of a bee,and different landscapes provide distinct sources of nutrition.Although many studies have demonstrated the apparent impacts of landscape change on the population dynamics and individual survival of the bees,the underpinning mechanisms remain largely unknown.On the other hand,an increasing body of literature has shown that bee gut symbionts are of great importance to the health of the host bees in absorbing nutrients and resisting pathogens.When foraging,pollinator bees are exposed to particular microbes from pollen and nectar which have been suggested to be a source of some bee gut symbionts and could be either probiotics or pathogens.Together with landscape-related nutrition and pesticides,environmental microbes have been reported to affect bee microbiomes significantly.A number of pilot studies suggest that landscape change could affect bee microbiota,thereby influencing host health.An important linkage,however,is missing between environmental microbiota,especially those associated with the flowers,and that of the bee gut in a changing habitat.It is worth exploring how gut microbiomes respond to landscape changes.This will hopefully help us identify landscape types that are friendly to bees,so proper land-use can be implemented to protect the bees.

51.Anticipated HIV stigma among HIV negative men who have sex with men in China: a cross-sectional study

Author:Liu, CC;Zhang, Y;Pan, SW;Cao, BL;Ong, JJ;Fu, HY;Wu, D;Fu, R;Wei, CY;Tucker, JD;Tang, WM


Abstract:BackgroundAnticipated HIV stigma, i.e., the expectation of adverse experiences from one's seroconversion, is associated with both negative psychological and behavioral outcomes. We know little about anticipated HIV stigma's relationship with emerging technologies, such as HIV self-testing (HIVST) and online sex-seeking platforms, that have become popular among populations that are disproportionately affected by HIV/AIDS. This study examined correlates of anticipated HIV stigma among Chinese men who have sex with men (MSM).MethodsIn July 2016, MSM, who were >= 16years old and self-reported as HIV negative or unknown, were recruited from a gay mobile phone application in China. Information regarding socio-demographics, sexual behaviors, sexual health service utilization, and anticipated HIV stigma were collected. Anticipated HIV stigma (i.e., negative attitude toward future stigmatization of HIV seroconversion by others) was measured as the mean score from a 7-item Likert-scale ranging from 1 (low) to 4 (high). Generalized linear models were conducted to examine the factors associated with the anticipated HIV stigma scores.ResultsOverall, 2006 men completed the survey. Most men completed high school (1308/2006, 65.2%%) and had an annual personal income of <= 9200 USD (1431/2006, 71.3%%). The mean anticipated HIV stigma score for the participants was 2.980.64. Using social media to seek sexual partners was associated with higher anticipated HIV stigma (Adjusted beta =0.11, 95%% confidence interval (CI): 0.05 to 0.17, p=0.001). HIV self-testing (Adjusted beta=-0.07, 95%%CI: -0.13 to -0.01, p=0.02) and having disclosed one's sexual orientation to a healthcare provider (Adjusted beta=-0.16, 95%%CI: -0.22 to -0.96, p<0.001) were associated with lower anticipated HIV stigma.Conclusion p id=Par Our data suggested that anticipated HIV stigma is still common among Chinese MSM not living with HIV. Tailored anti-HIV stigma campaigns on social media are especially needed, and the promotion of HIVST may be a promising approach.

52.An extended Last Glacial Maximum in subtropical Australia

Author:Petherick, LM;Moss, PT;McGowan, HA


Abstract:A continuous, record encompassing the termination of the Last Glacial cycle (defined here as ca. 30 -18 cal. kyr BP) has been developed using multiple proxies (viz. clastic sediment flux, grain size, moisture content, pollen and charcoal) archived in lake sediments from Tortoise Lagoon, North Stradbroke Island, Australia. The record indicates an extended Last Glacial Maximum, with an onset at ca. 30 kyr BP. The presence of rainforest and arboreal taxa for the 30-18 kyr BP period indicate a positive moisture balance, while the presence of the now regionally extinct Asteraceae (Tubuliflorae) and Tubulifloridites pleistocenicus indicate relatively cool temperatures. Total clastic sediment flux and the vegetation assemblage suggest that, at least in subtropical Australia, the Last Glacial Maximum was characterized by two peaks in aridity at ca. 29-26 kyr BP and 24.5-20 kyr BP. (C) 2016 Elsevier Ltd and INQUA. All rights reserved.

53.Diversity and seasonal changes in carabid assemblages of a mature, secondary and plantation forest mosaic in the Zhangguangcai Mountains in northeastern China

Author:Sun, XJ;Diekman, M;Yan, X;Zou, Y;Sang, WG;Axmacher, JC


Abstract:While China is promoting the re-establishment of forests across the country on a globally unprecedented scale, the biodiversity harboured by the resulting secondary and plantation forests remains poorly understood. Here, we assess the carabid diversity at Zhangguangcai Mountains in northeastern China that comprise a unique mosaic of mature forest remnants, secondary forests and forest plantations. We located pitfall traps in five distinct forest types: mature conifer and mature mixed forest, secondary mixed forest, secondary broadleaved forest dominated by birch (Betula platyphylla) and poplar (Populus davidiana), and in larch plantations. We recorded 9073 carabid beetles representing 42 species, with richness, abundance and diversity of ground beetles all peaking in secondary broadleaved forests. Assemblages sampled in larch plantations were least species rich, but species extrapolation curves indicate a potentially high overall species richness. Carabid communities were clearly differentiated according to forest type, with larch plantations and secondary broadleaved forests containing beetle assemblages distinct from the other three forest types, while the mixed secondary and mature forest types harboured similar assemblages. Carabid communities also showed a clear seasonality in all forest types, with the plantation forest communities remaining distinctly different from the clustered communities of the mature and mixed secondary forest types throughout the year. Broadleaved secondary forest assemblages occupy an intermediate position throughout the sampling season.

54.Ethnicity and HIV vulnerabilities among men who have sex with men in China

Author:Pan, SW;Carpiano, RM;Li, DL;Zhang, Z;Schechter, MT;Spittal, PM;Ruan, YH


Abstract:Ethnic affiliation can define sociocultural boundaries and contribute to the HIV vulnerabilities faced by men who have sex with men (MSM). This study investigated the influence of ethnic affiliation on HIV vulnerabilities among MSM in North China. Our study analyzed a cross-sectional survey of MSM (n=398) in two major North China cities. We examined associations between ethnic affiliation and (a) HIV status, (b) sexual behaviors and experiences, and (c) substance use. Compared to ethnic majority Han MSM: MSM belonging to ethnic minority groups of South China had significantly greater odds of HIV infection (AOR: 7.40; 95%% CI: 2.33-23.47) and experience of forced sex (AOR: 3.27; 95%% CI: 1.12-9.52). Compared to ethnic majority Han MSM, Ethnic Hui MSM had significantly lower odds of condomless anal sex (AOR: 0.41; 95%% CI: 0.21-0.82) and significantly greater odds of circumcision (AOR: 2.62; 95%% CI: 1.24-5.51). HIV prevalence and riskier sexual behaviors among MSM in China appear to vary significantly by ethnic affiliation. Current epidemiological practices of aggregating all ethnic minority groups in China into a single category may be masking important interethnic differences in HIV risk, and precluding opportunities for more culturally appropriate interventions.

55.Inter-Specific Competition, but Not Different Soil Microbial Communities, Affects N Chemical Forms Uptake by Competing Graminoids of Upland Grasslands

Author:Medina-Roldan, E;Bardgett, RD

Source:PLOS ONE,2012,Vol.7

Abstract:Evidence that plants differ in their ability to take up both organic (ON) and inorganic (IN) forms of nitrogen (N) has increased ecologists' interest on resource-based plant competition. However, whether plant uptake of IN and ON responds to differences in soil microbial community composition and/or functioning has not yet been explored, despite soil microbes playing a key role in N cycling. Here, we report results from a competition experiment testing the hypothesis that soil microbial communities differing in metabolic activity as a result of long-term differences to grazing exposure could modify N uptake of Eriophorum vaginatum L. and Nardus stricta L. These graminoids co-occur on nutrient-poor, mountain grasslands where E. vaginatum decreases and N. stricta increases in response to long-term grazing. We inoculated sterilised soil with soil microbial communities from continuously grazed and ungrazed grasslands and planted soils with both E. vaginatum and N. stricta, and then tracked uptake of isotopically labelled NH4+ (IN) and glycine (ON) into plant tissues. The metabolically different microbial communities had no effect on N uptake by either of the graminoids, which might suggest functional equivalence of soil microbes in their impacts on plant N uptake. Consistent with its dominance in soils with greater concentrations of ON relative to IN in the soluble N pool, Eriophorum vaginatum took up more glycine than N. stricta. Nardus stricta reduced the glycine proportion taken up by E. vaginatum, thus increasing niche overlap in N usage between these species. Local abundances of these species in mountain grasslands are principally controlled by grazing and soil moisture, although our results suggest that changes in the relative availability of ON to IN can also play a role. Our results also suggest that coexistence of these species in mountain grasslands is likely based on non-equilibrium mechanisms such as disturbance and/or soil heterogeneity.

56.Acetotrophic methanogens are sensitive to long-term nickel contamination in paddy soil

Author:Chen, XP;Yu, J;Chen, Z;Zhang, HM;Cheng, WD;Bai, FY;Zheng, Y;Ahamed, KI;He, CQ;Liu, XY


Abstract:Paddy soil accounts for approximately one-fifth of the world's cultivated area and faces a serious threat from nickel (Ni). Ni pollution has an impact on the activity, composition and emission of methanogens in paddy, which is a major natural source of methane (CH4) emissions. We combined a high-throughput sequencing approach and laboratory incubation methods to evaluate the impact of long-term Ni pollution on the methanogenic archaeal community in paddy soil. The highest rate of CH(4)production was 697 mg kg(-1)of dry soil per d with the addition of sodium acetate at 50 mg kg(-1)of Ni, which was significantly negatively correlated with the total and available Ni (p< 0.05). While the highest CH(4)production rates were 485 and 544 mg kg(-1)of dry soil per d with the addition of sodium formate and methanol, respectively, there was no significant difference in the CH(4)production rate and maximum CH(4)accumulation between the different Ni additions. Heavy pollution with 500 mg kg(-1)of Ni unexceptionally inhibited the relative abundance of various genera of methanogens (22.2%% in total). The abundance of acetotrophicMethanosaetadecreased with an increasing concentration of Ni (3.25-1.11%%). The diverse nutrient types of species belonging toMethanosarcinawere the highest under treatment with Ni200 (18.0%%), and lowest in the soil with 500 mg kg(-1)of Ni (2.8%%). Similarly, the abundances of the most abundant hydrogenotrophic methanogens ofMethanocellaleswere relatively high with Ni200 (26.2%%) compared with those with Ni500 (5.4%%). ThemcrA gene was enriched under the light pollution treatment (50 mg kg(-1)of Ni, 6.73 x 10(7)+/- 9.0 x 10(6)copies per g of soil) compared with the control (4.18 x 10(7)+/- 5.1 x 10(6)copies per g of soil). These results indicate that the long-term pollution by Ni has an impact on the activity and composition of methanogens with heavy Ni pollution, and in particular, acetotrophic methanogens are sensitive to Ni pollution in paddy soil.

57.One-step fabrication of binder-free air cathode for microbial fuel cells by using balsa wood biochar

Author:Chang, HC;Gustave, W;Yuan, ZF;Xiao, Y;Chen, Z


Abstract:Efficient cathode performance is crucial for the power generation of microbial fuel cells (MFCs). Therefore, the development of a cost effective and efficient cathode is urgently needed for the wider application of MFCs. In this study, a novel biochar air cathode with naturally porous structure and high oxygen reduction reaction (ORR) activity prepared from the pyrolysis of Balsa Wood chip at 800 degrees C was proposed. The biochar chips can be installed directly in the MFC as an air cathode without the need to apply expensive catalysts, binders and a gas diffusion layers. In the single chamber MFC tests, the biochar air cathode achieved a maximum power density of 200 mW/m(2) which was comparable to those of the other biochar based air cathodes. Moreover, when they were used in soil MFCs, our results showed that the chip thickness had effect on the performance of the soil MFCs. The 3.5 mm biochar produced the highest power density of 72 mW/m(2), which was 45%% higher than that of the soil MFC equipped with common carbon felt floating cathode. These findings demonstrate for the first time, that whole biochar chip could be considered as an effective and environmental-friendly material for the production of binder- and catalysis-free air cathode. (C) 2020 Elsevier B.V. All rights reserved.

58.Water quality change along urbanization processes according to pesticides and PPCPs distribution within different population area in Suzhou, China

Author:Qin, SJ;Jeong, HJ


59.Pathways to optimising antibiotic use in rural China: identifying key determinants in community and clinical settings, a mixed methods study protocol

Author:Zhao, LH;Kwiatkowska, RM;Chai, J;Cabral, C;Chen, MX;Bowker, K;Coope, C;Shen, JL;Shen, XR;Cheng, J;Feng, R;Kadetz, P;MacGowan, A;Oliver, I;Hickman, M;Wang, DB;Lambert, H

Source:BMJ OPEN,2019,Vol.9

Abstract:Introduction This study aims to investigate patterns of antibiotic treatment-seeking, describe current levels of and drivers for antibiotic use for common infections (respiratory tract and urinary tract infections) and test the feasibility of determining the prevalence and epidemiology of antimicrobial resistance (AMR) in rural areas of Anhui province, in order to identify potential interventions to promote antibiotic stewardship and reduce the burden of AMR in China. Methods and analysis We will conduct direct observations, structured and semistructured interviews in retail pharmacies, village clinics and township health centres to investigate treatment-seeking and antibiotic use. Clinical isolates from 1550 sputum, throat swab and urine samples taken from consenting patients at village and township health centres will be analysed to identify bacterial pathogens and ascertain antibiotic susceptibilities. Healthcare records will be surveyed for a subsample of those recruited to the study to assess their completeness and accuracy. Ethics and dissemination The full research protocol has been reviewed and approved by the Biomedical Ethics Committee of Anhui Medical University (reference number: 20170271). Participation of patients and doctors is voluntary and written informed consent is sought from all participants. Findings from the study will be disseminated through academic routes including peer-reviewed publications and conference presentations, via tailored research summaries for health professionals, health service managers and policymakers and through an end of project impact workshop with local and regional stakeholders to identify key messages and priorities for action.

60.The response of grassland mycorrhizal fungal abundance to a range of long-term grazing intensities

Author:Faghihinia, M;Zou, Y;Chen, Z;Bai, YF;Li, WH;Marrs, R;Staddon, PL


Abstract:Keystone root symbiotic arbuscular mycorrhizal fungi play a major role in maintaining plant biodiversity, increasing plant productivity and enhancing storage of carbon in soil. AM fungi are ubiquitous and found in most ecosystems including grasslands currently experiencing increasing pressures form human activity. Grazing is known to impact AM fungi but very little is known about how AM fungi are affected by different levels of grazing intensity. Here we report on results from a long-term experimental site in a typical steppe in the north of China, containing seven levels of field-manipulated grazing intensities maintained for over 13 years. We assessed arbuscular mycorrhizal fungal abundance, represented by soil hyphal length density and mycorrhizal root colonization (mycorrhizal root frequency, intensity and arbuscule intensity) within the farm-scale field experiment. We also measured environmental variables to explain the responses of mycorrhizal fungi to grazing intensity. Our results showed that with an increase in grazing intensity, soil hyphal length density linearly decreased. There was, however, no significant trend for mycorrhizal root colonization variables in relation to grazing intensity. Mycorrhizal root frequency was negatively correlated with topographic-induced changes in soil nitrogen and phosphorus, while arbuscule intensity was marginally negatively correlated with soil available phosphorus. Further, we found a possible hump-shaped relationship between the ratio of external to internal AM fungal structures and grazing intensity. Our finding showed that external AM fungal structure was clearly impacted by grazing intensity but that this was not the case for internal mycorrhizal structures. This indicated that mycorrhizal functioning was impacted by the intensity of grazing as the mycorrhizal structures responded differently. Indeed the ratio of the foraging extra-radical mycorrhizal hyphae to intra-radical mycorrhizal structures was highest at moderate grazing intensity but strongly decreased by high grazing intensity. Our study suggests that the impacts of grazing intensity on the plant-AMF association could lead to further knock-on effects on the plant-soil system via the feedbacks that exist between plant and AMF communities.
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