Find Research Output

Research Output
  • All
  • Scholar Profiles
  • Research Units
  • Research Output
Filter
Department Publication Year Content Type Data Sources

SELECTED FILTERS

Department of Health and Environmental Sciences
Clear all

1.Prepared for PrEP: preferences for HIV pre-exposure prophylaxis among Chinese men who have sex with men in an online national survey (vol 19, 1057, 2019)

Author:Huang, WT;Wu, D;Ong, JJ;Smith, MK;Yang, F;Fu, HY;Tang, WM;Pan, S;Tucker, JD

Source:BMC INFECTIOUS DISEASES,2020,Vol.20

Abstract:© 2020 The Author(s). After publication of the original article [1], the authors would like to add a co-author, Dr. Stephen Pan, who contributed sufficiently to this manuscript. He was not included in the original article due to a miscommunication.

2.Total phosphorus concentrations in surface water of typical agro- and forest ecosystems in China, 2004-2010

Author:Xie Juan;Zhang Xinyu;Xu Zhiwei;Yuan Guofu;Tang Xinzhai;Sun Xiaomin;Ballantine D J

Source:Frontiers of Environmental Science & Engineering,2014,Vol.8

Abstract:The concentrations of total phosphorus (TP) from 83 surface water sampling sites in 29 of the Chinese Ecosystem Research Network (CERN) monitored ecosystems, representing typical agro- and forest ecosystems, were assessed using monitoring data collected between 2004 and 2010 from still and flowing surface water. Results showed that, TP concentrations were significantly higher in agro-ecosystems than those in forest ecosystems both for still and flowing surface water. For agroecosystems, TP concentrations in the southern area were significantly higher than those in the northern and northwestern areas for both still and flowing surface water, however no distinct spatial pattern was observed for forest ecosystems. In general, the median values of TP within agro- and forest ecosystems did not exceed the Class V guideline for still (0.2 mg·L~(-1)) or flowing (0.4 mg·L~(-1)) surface water, however, surface water at some agroecosystem sampling sites was frequently polluted by TP. Elevated concentrations were mainly found in still surface water at the Changshu, Fukang, Linze and Naiman monitored ecosystems, where exceedance (>0.2 mg·L~(-1)) frequencies varied from 43%% to 78%%. For flowing water, elevated TP concentrations were found at the Hailun, Changshu and Shapotou monitored ecosystems, where exceedance (>0.4 mg·L~(-1)) frequencies varied from 29%% to 100%%. Irrational fertilization, frequent irrigation and livestock manure input might be the main contributors of high TP concentrations in these areas, and reduced fertilizer applications, improvements in irrigation practices and centralized treatment of animal waste are necessary to control P loss in these TP vulnerable zones.

3.Whole-cell bioreporters and risk assessment of environmental pollution: A proof-of-concept study using lead (vol 229, pg 902, 2017)

Author:Zhang, XK;Qin, BQ;Deng, JM;Wells, M

Source:ENVIRONMENTAL POLLUTION,2020,Vol.257

Abstract:The authors regret that we incorrectly identified the wild type in the paper. In the methods, the first sentence of the passage in section 2.1 should read In this research, Escherichia coli strain zntA, which has the capacity to emit a dose-dependent bioluminescence in response to available Pb (Riether et al., 2001), was used for Pb bioavailability evaluation. The subsequent mentions of the wild type Cupriavidus metallidurans should be Escherichia coli. The authors would like to apologise for any inconvenience caused. © 2019 Elsevier Ltd

4.Anthropogenic stressors affect fungal more than bacterial communities in decaying leaf litter: A stream mesocosm experiment

Author:Juvigny-Khenafou, NPD;Zhang, YX;Piggott, JJ;Atkinson, D;Matthaei, CD;Van Bael, SA;Wu, NC

Source:SCIENCE OF THE TOTAL ENVIRONMENT,2020,Vol.716

Abstract:Despite the progress made in environmental microbiology techniques and knowledge, the succession and functional changes of the microbial community under multiple stressors are still poorly understood. This is a substantial knowledge gap as microbial communities regulate the biogeochemistry of stream ecosystems. Our study assessed the structural and temporal changes in stream fungal and bacterial communities associated with decomposing leaf litter under a multiple-stressor scenario. We conducted a fully crossed 4-factor experiment in 64 flow-through mesocosms fed by a pristine montane stream (21 days of colonisation, 21 days of manipulations) and investigated the effects of nutrient enrichment, flow velocity reduction and sedimentation after 2 and 3 weeks of stressor exposure. We used high-throughput sequencing and metabarcoding techniques (16S and 18S rRNA genes) to identify changes in microbial community composition. Our results indicate that (1) shifts in relative abundances of the pre-existing terrestrial microbial community, rather than changes in community identity, drove the observed responses to stressors; (2) changes in relative abundances within the microbial community paralleled decomposition rate patterns with time; (3) both fungal and bacterial communities had a certain resistance to stressors, as indicated by relatively minor changes in alpha diversity or multivariate community structure; (4) overall, stressor interactions were more common than stressor main effects when affecting microbial diversity metrics or abundant individual genera; and (5) stressor effects on microbes often changed from 2 weeks to 3 weeks of stressor exposure, with several response patterns being reversed. Our study suggests that future research should focus more on understanding the temporal dynamics of fungal and bacterial communities and how they relate to ecosystem processes to advance our under- standing of the mechanisms associated with multiple-stressor interactions. (C) 2019 Elsevier B.V. All rights reserved.

5.A global synthesis reveals biodiversity-mediated benefits for crop production

Author:Dainese, M;Martin, EA;Aizen, MA;Albrecht, M;Bartomeus, I;Bommarco, R;Carvalheiro, LG;Chaplin-Kramer, R;Gagic, V;Garibaldi, LA;Ghazoul, J;Grab, H;Jonsson, M;Karp, DS;Kennedy, CM;Kleijn, D;Kremen, C;Landis, DA;Letourneau, DK;Marini, L;Poveda, K;Rader, R;Smith, HG;Tscharntke, T;Andersson, GKS;Badenhausser, I;Baensch, S;Bezerra, ADM;Bianchi, FJJA;Boreux, V;Bretagnolle, V;Caballero-Lopez, B;Cavigliasso, P;Cetkovic, A;Chacoff, NP;Classen, A;Cusser, S;Silva, FDDE;de Groot, GA;Dudenhoffer, JH;Ekroos, J;Fijen, T;Franck, P;Freitas, BM;Garratt, MPD;Gratton, C;Hipolito, J;Holzschuh, A;Hunt, L;Iverson, AL;Jha, S;Keasar, T;Kim, TN;Kishinevsky, M;Klatt, BK;Klein, AM;Krewenka, KM;Krishnan, S;Larsen, AE;Lavigne, C;Liere, H;Maas, B;Mallinger, RE;Pachon, EM;Martinez-Salinas, A;Meehan, TD;Mitchell, MGE;Molina, GAR;Nesper, M;Nilsson, L;O'Rourke, ME;Peters, MK;Plecas, M;Potts, SG;Ramos, DD;Rosenheim, JA;Rundlof, M;Rusch, A;Saez, A;Scheper, J;Schleuning, M;Schmack, JM;Sciligo, AR;Seymour, C;Stanley, DA;Stewart, R;Stout, JC;Sutter, L;Takada, MB;Taki, H;Tamburini, G;Tschumi, M;Viana, BF;Westphal, C;Willcox, BK;Wratten, SD;Yoshioka, A;Zaragoza-Trello, C;Zhang, W;Zou, Y;Steffan-Dewenter, I

Source:SCIENCE ADVANCES,2019,Vol.5

Abstract:Human land use threatens global biodiversity and compromises multiple ecosystem functions critical to food production. Whether crop yield-related ecosystem services can be maintained by a few dominant species or rely on high richness remains unclear. Using a global database from 89 studies (with 1475 locations), we partition the relative importance of species richness, abundance, and dominance for pollination; biological pest control; and final yields in the context of ongoing land-use change. Pollinator and enemy richness directly supported ecosystem services in addition to and independent of abundance and dominance. Up to 50%% of the negative effects of landscape simplification on ecosystem services was due to richness losses of service-providing organisms, with negative consequences for crop yields. Maintaining the biodiversity of ecosystem service providers is therefore vital to sustain the flow of key agroecosystem benefits to society.

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

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

Source:STOCHASTIC ENVIRONMENTAL RESEARCH AND RISK ASSESSMENT,2017,Vol.31

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.

7.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.

8.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

Source:BMC INFECTIOUS DISEASES,2020,Vol.20

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.

9.An extended Last Glacial Maximum in subtropical Australia

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

Source:QUATERNARY INTERNATIONAL,2017,Vol.432

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.

10.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

Source:ENVIRONMENTAL SCIENCE-PROCESSES & IMPACTS,2020,Vol.22

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.

11.Antibiotic resistance genes in manure-amended soil and vegetables at harvest

Author:Wang, FH;Qiao, M;Chen, Z;Su, JQ;Zhu, YG

Source:JOURNAL OF HAZARDOUS MATERIALS,2015,Vol.299

Abstract:Lettuce and endive, which can be eaten raw, were planted on the manure-amended soil in order to explore the influence of plants on the abundance of antibiotic resistance genes (ARGs) in bulk soil and rhizosphere soil, and the occurrence of ARGs on harvested vegetables. Twelve ARGs and one integrase gene Until) were detected in all soil samples. Five ARGs (sulI, tetG, tetC, tetA, and tetM) showed lower abundance in the soil with plants than those without. ARGs and intI1 gene were also detected on harvested vegetables grown in manure-amended soil, including endophytes and phyllosphere microorganisms. The results demonstrated that planting had an effect on the distribution of ARGs in manure-amended soil, and ARGs were detected on harvested vegetables after growing in manure-amended soil, which had potential threat to human health. (C) 2015 Elsevier B.V. All rights reserved.

12.A photovoltaic self-powered gas sensor based on a single-walled carbon nanotube/Si heterojunction

Author:Liu, L;Li, GH;Wang, Y;Wang, YY;Li, T;Zhang, T;Qin, SJ

Source:NANOSCALE,2017,Vol.9

Abstract:We present a novel photovoltaic self-powered gas sensor based on a p-type single-walled carbon nanotube (SWNT) and n-type silicon (n-Si) heterojunction. The energy from visible light suffices to drive the device owing to a built-in electric field (BEF) induced by the differences between the Fermi levels of SWNTs and n-Si.

13.Assessment of self-medication practices with antibiotics among undergraduate university students in Rwanda

Author:Tuyishimire, J;Okoya, F;Adebayo, AY;Humura, F;Lucero-Prisno, DE

Source:PAN AFRICAN MEDICAL JOURNAL,2019,Vol.33

Abstract:Introduction: antimicrobial resistance (AR) is on a rise as one of the major global public health threats. It is therefore important to assess contributory factors to the rise in the cases of resistance reported. The main objective of this study was to assess the self-medication practices with antibiotics among the University of Rwanda students in Huye Campus. Methods: a sample of 570 students from all levels and colleges of the University of Rwanda in Huye Campus were selected using a simple random sampling to participate in this study. A questionnaire was administered to be answered individually by the consented respondents where the self-medication practices with antibiotics in the past 6 months were assessed. The results were statistically analyzed using SPSS v.16. Results: the study showed that 12.1%% (n=69) practiced self-medication with antibiotics. The major reason for self-medication with antibiotics was illness not serious to have a consultation (50.72%%). The main diseases being treated were common cold/fever/cough (47.83%%). The most used antibiotic for self-medication was Amoxicillin capsules (59.42%%), while the main source of antibiotics was the community pharmacy (72.42%%). Conclusion: self-medication with antibiotics is not uncommon among the university students. Regarding the main reasons of self-medication with antibiotics, diseases being treated, and the antibiotics used, it was found that all these may be related to the students' lack of knowledge about the need for rational use of antibiotics and a study was needed to confirm it.

14.Adequate Iodine Intake among Young Adults in Jiangsu Province, China Despite a Medium Iodine Knowledge Score

Author:Jin, YF;Luo, XQ;Ma, ZF;Dong, ZH;Carciofo, R;Li, XL;Skeaff, S

Source:EUROPEAN JOURNAL OF INVESTIGATION IN HEALTH PSYCHOLOGY AND EDUCATION,2020,Vol.10

Abstract:Lack of iodine knowledge might be a risk factor for inadequate iodine intake in populations. Therefore, we aimed to determine the relationship between iodine knowledge and intake in young Chinese adults. A cross-sectional study was conducted in Suzhou, China. Iodine intake was assessed using a validated 33-item iodine-specific Chinese food frequency questionnaire (FFQ) and iodine knowledge was determined using a Chinese iodine knowledge questionnaire. A total of 150 participants (mean age 20.3 years) completed the study. The median iodine intake plus iodized salt was 260 mu g /d, indicating iodine sufficiency ( >150 mu g/d). The median iodine knowledge score was 16/24, suggesting a medium level of knowledge. The majority of participants correctly recognized fish and seafood (95%%) and iodized salt (83%%) as the most important dietary iodine sources. After adjusting for age and sex, studying in the science cluster and having received iodine education were the predictors of having a higher iodine knowledge score, with adjusted odd ratios (OR) of 4.33 (1.49, 12.61) and 2.73 (1.21, 6.14), respectively. In conclusion, young Chinese adults had an adequate iodine intake despite a medium iodine knowledge score. This study provides support that iodine fortification in China has been successful, but further research is required to more fully substantiate this finding.

15.Arsenic mitigation in paddy soils by using microbial fuel cells

Author:Gustave, W;Yuan, ZF;Sekar, R;Chang, HC;Zhang, J;Wells, M;Ren, YX;Chen, Z

Source:ENVIRONMENTAL POLLUTION,2018,Vol.238

Abstract:Arsenic (As) behavior in paddy soils couples with the redox process of iron (Fe) minerals. When soil is flooded, Fe oxides are transformed to soluble ferrous ions by accepting the electrons from Fe reducers. This process can significantly affect the fate of As in paddy fields. In this study, we show a novel technique to manipulate the Fe redox processes in paddy soils by deploying soil microbial fuel cells (sMFC). The results showed that the sMFC bioanode can significantly decrease the release of Fe and As into soil porewater. Iron and As contents around sMFC anode were 65.0%% and 47.0%% of the control respectively at day 50. The observed phenomenon would be explained by a competition for organic substrate between sMFC bioanode and the iron- and arsenic-reducing bacteria in the soils. In the vicinity of bioanode, organic matter removal efficiencies were 10.3%% and 14.0%% higher than the control for lost on ignition carbon and total organic carbon respectively. Sequencing of the 16S rRNA genes suggested that the influence of bioanodes on bulk soil bacterial community structure was minimal. Moreover, during the experiment a maximum current and power density of 0.31 mA and 12.0 mWm(-2) were obtained, respectively. This study shows a novel way to limit the release of Fe and As in soils porewater and simultaneously generate electricity. (C) 2018 Elsevier Ltd. All rights reserved.

16.Arsenic alleviation in rice by using paddy soil microbial fuel cells

Author:Gustave, W;Yuan, ZF;Ren, YX;Sekar, R;Zhang, J;Chen, Z

Source:PLANT AND SOIL,2019,Vol.441

Abstract:Background and aims Rice (Oryza sativa L.) consumption is a major route of dietary exposure to arsenic (As) in humans. One main reason for the high accumulation of As in rice grain is the high bioavailability of As in porewater of flooded paddy soil. Recently, it has been shown that the application of soil microbial fuel cell (sMFC) can significantly reduce soil porewater As concentration, however, the effect of sMFC on As accumulation in rice is unknown. Hence, this study was aimed at reducing the As uptake in rice grown in As contaminated soil by sMFCs. Methods A pot experiment was performed to investigate As distribution in rice tissues and the functional microbial communities in soil when the sMFC was installed. The As in the soil porewater and rice plant parts were analyzed. 16S rRNA sequencing and Quantitative PCR were used to examine the microbial community and to quantify the relative abundance of As resistance genes in the rhizosphere, respectively. Results The results suggest that the sMFC can simultaneously work as an electricity generator and As mitigator. The total As concentrations in the stems, leaves, husks, and rice grains were significantly decreased by 53.4%%, 44.7%%, 62.6%%, and 67.9%%, respectively in the plants with sMFC compared to the control. This decrease in As accumulation in the sMFC treatment may be explained by the decrease in the soil porewater dissolve organic matter content and abundance of As reducing gene (arsC). Moreover, known As reducing classes such as Clostridia, Bacilli and Thermoleophilia were significantly enhanced in the control treatment. Conclusions Integrating the sMFC in rice paddy soil offers a promising way to mitigate As accumulation in rice tissue and reduce dietary As exposure, while simultaneously producing electricity.

17.Arsenic modulates the composition of anode-respiring bacterial community during dry-wet cycles in paddy soils

Author:Wang, YJ;Chen, Z;Liu, PP;Sun, GX;Ding, LJ;Zhu, YG

Source:JOURNAL OF SOILS AND SEDIMENTS,2016,Vol.16

Abstract:Bacteria able to extracelluar respiration, which could be enriched in the anode of microbial fuel cells (MFCs), play important roles in dissimilatory iron reduction and arsenic (As) desorption in paddy soils. However, the response of the bacteria to As pollution is unknown. Using soil MFCs to investigate the effects of As on anode respiring bacteria (ARB) communities in paddy soils exposed to As stress. The soil MFC performances were evaluated by electrochemical methods. The bacterial community compositions on anodes were studied using Illumina sequencing. In wet 1 phase, polarization curves of MFCs showed cathode potentials were enhanced at low As exposure but inhibited at high As exposure. In the meantime, anode potentials increased with As levels. The dry-wet alternation reduced As levels in porewater and their impacts on electrodes microorganisms. Arsenic addition significantly influenced the anode microbial communities. After dry-wet cycles, Deltaproteobacteria dominated in the anode with high As. The dynamic changes of the communities on cathodes and anodes of soil MFCs in paddy soils with different As addition might be explained by their different mechanisms for As detoxification. These results provide new insights into the microbial evolution in As-contaminated paddy soils.

18.A wind tunnel study of aeolian sediment transport response to unsteady winds

Author:Li, BL;Neuman, CM

Source:GEOMORPHOLOGY,2014,Vol.214

Abstract:Although moderate attention has been paid to the response of the aeolian mass transport rate to wind gusts, it is still unclear how the particle size and volumetric concentration affect this relation. Very little is known about the response time of the particle speed, and specifically, how the sensor scale and elevation affect measurements of this variable. The present study addresses this knowledge gap through a series of wind tunnel experiments in which a gusty wind was generated by programming the fan motor to adjust to a randomly selected rpm every 10 s. Beds consisting of either medium or coarse sand were investigated through synchronous, co-located measurements of the local wind speed and particle speed/count rate obtained via a customized laser Doppler anemometry (LDA) system. The vertically integrated sand transport rate (Q) and the wind speed in the freestream were quantified using a passive sand trap and pitot tube, respectively. The results of the experiments indicate that the response of the aeolian transport system to wind gusts is generally faster in terms of the particle speed than the mass transport rate, while the degree of correlation is found to vary with the sensor elevation, as well as with the particle size and volumetric concentration. In essence, the coupling within the transport system is demonstrated to be strongly scale dependent. (C) 2014 Elsevier B.V. All rights reserved.

19.Assessment of Iodine Status among Pregnant Women and Neonates Using Neonatal Thyrotropin (TSH) in Mainland China after the Introduction of New Revised Universal Salt Iodisation (USI) in 2012: A Re-Emergence of Iodine Deficiency?

Author:Zhou, H;Ma, ZF;Lu, YM;Pan, BY;Shao, J;Wang, LY;Du, YY;Zhao, QH

Source:INTERNATIONAL JOURNAL OF ENDOCRINOLOGY,2019,Vol.2019

Abstract:Iodine deficiency during pregnancy can cause iodine deficiency disorders (IDD). However, it is unclear about iodine and thyroid status of Chinese pregnant women and neonates after the implementation of the revised universal salt iodisation (USI) level in 2012. Therefore, the aim of the cross-sectional study was to determine iodine nutrition and thyroid status among pregnant women and their neonates in China after the implementation of USI. Medical records of pregnant women and neonates in Northern Jiangsu People's Hospital between January 2016 and December 2017 were reviewed and included. We included 3060 mother-and-newborn pairs in the study. Mean age of participants was 28.2 +/- 4.1 years. TSH, FT3, and FT4 of participants were within normal reference range. The overall mean neonatal TSH, birth weight, and prevalence of low birth weight (LBW) were 4.86 +/- 2.06 mIU/L, 3358 +/- 455 g, and 3.2%%, respectively. The prevalence of neonatal TSH values >5 mIU/L was 29.3%%, suggesting iodine deficiency in the region. In conclusion, our results indicated iodine deficiency in the region, according to the neonatal TSH cutoff recommended by WHO/UNICEF/IGD. More efforts are urgently required to improve iodine status of pregnant women in the region in order to prevent a re-emergence of iodine deficiency.

20.Aerodynamics and morphodynamics of sand fences: A review

Author:Li, BL;Sherman, DJ

Source:AEOLIAN RESEARCH,2015,Vol.17

Abstract:This paper reviews literature on the aerodynamics and morphodynamics of sand fences. We consider both wind fences for reducing wind erosion, and sand-trapping fences for controlling sand deposition. There has been substantial trial-and-error research based upon installations of sand fences, but only limited research on the fence and site attributes that provide the main aerodynamic and morphodynamic controls of interactions between aeolian systems and the fences. Such attributes include: fence porosity, height, length, width, opening size and geometry, porosity distribution, and external factors such as incoming flow characteristics, roughness length, atmospheric stability, grain size and local landform change. Considerations for the optimal design for both wind fences and sand-trapping fences are presented. (C) 2014 Elsevier B.V. All rights reserved.
Total 206 results found
Copyright 2006-2020 © Xi'an Jiaotong-Liverpool University 苏ICP备07016150号-1 京公网安备 11010102002019号