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Department of Health and Environmental Sciences
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1.Urbanization Impacts the Physicochemical Characteristics and Abundance of Fecal Markers and Bacterial Pathogens in Surface Water

Author:Yuan, TM;Vadde, KK;Tonkin, JD;Wang, JJ;Lu, J;Zhang, ZM;Zhang, YX;McCarthy, AJ;Sekar, R


Abstract:Urbanization is increasing worldwide and is happening at a rapid rate in China in line with economic development. Urbanization can lead to major changes in freshwater environments through multiple chemical and microbial contaminants. We assessed the impact of urbanization on physicochemical characteristics and microbial loading in canals in Suzhou, a city that has experienced rapid urbanization in recent decades. Nine sampling locations covering three urban intensity classes (high, medium and low) in Suzhou were selected for field studies and three locations in Huangshan (natural reserve) were included as pristine control locations. Water samples were collected for physicochemical, microbiological and molecular analyses. Compared to medium and low urbanization sites, there were statistically significant higher levels of nutrients and total and thermotolerant coliforms (or fecal coliforms) in highly urbanized locations. The effect of urbanization was also apparent in the abundances of human-associated fecal markers and bacterial pathogens in water samples from highly urbanized locations. These results correlated well with land use types and anthropogenic activities at the sampling sites. The overall results indicate that urbanization negatively impacts water quality, providing high levels of nutrients and a microbial load that includes fecal markers and pathogens.

2.Psychometric Evaluation of Chinese-Language 44-Item and 10-Item Big Five Personality Inventories, Including Correlations with Chronotype, Mindfulness and Mind Wandering

Author:Carciofo, R;Yang, JY;Song, N;Du, F;Zhang, K

Source:PLOS ONE,2016,Vol.11

Abstract:The 44-item and 10-item Big Five Inventory (BFI) personality scales are widely used, but there is a lack of psychometric data for Chinese versions. Eight surveys (total N = 2,496, aged 18-82), assessed a Chinese-language BFI-44 and/or an independently translated Chinese-language BFI-10. Most BFI-44 items loaded strongly or predominantly on the expected dimension, and values of Cronbach's alpha ranged .698-. 807. Test-retest coefficients ranged .694-.770 (BFI-44), and .515-.873 (BFI-10). The BFI-44 and BFI-10 showed good convergent and discriminant correlations, and expected associations with gender (females higher for agreeableness and neuroticism), and age (older age associated with more conscientiousness and agreeableness, and also less neuroticism and openness). Additionally, predicted correlations were found with chronotype (morningness positive with conscientiousness), mindfulness (negative with neuroticism, positive with conscientiousness), and mind wandering/daydreaming frequency (negative with conscientiousness, positive with neuroticism). Exploratory analysis found that the Self-discipline facet of conscientiousness positively correlated with morningness and mindfulness, and negatively correlated with mind wandering/daydreaming frequency. Furthermore, Self-discipline was found to be a mediator in the relationships between chronotype and mindfulness, and chronotype and mind wandering/daydreaming frequency. Overall, the results support the utility of the BFI-44 and BFI-10 for Chinese-language big five personality research.

3.Morningness-eveningness and affect: the mediating roles of sleep quality and metacognitive beliefs

Author:Carciofo, R


Abstract:Morningness (a preference for earlier rise and bed times) is associated with well-being, better sleep quality, and positive affect, while eveningness is associated with poor sleep quality, negative mood, maladaptive behaviours, and psychological disorder. The current study investigated: (1) whether eveningness is associated with more maladaptive metacognitive beliefs; (2) whether maladaptive metacognitive beliefs and sleep quality are related to associations between morningness-eveningness and affect. An online survey with questionnaire measures of morningness-eveningness, affect, sleep quality, and metacognitive beliefs was completed by 591 undergraduate students. More morningness correlated with more positive affect, while more eveningness correlated with more negative affect and poor sleep quality. Eveningness also showed small correlations with having less cognitive confidence and with metacognitive beliefs about uncontrollable thoughts. Mediation analysis showed that cognitive confidence and beliefs about uncontrollable thoughts, together with poor sleep quality (especially subjective sleep quality and daytime dysfunction), were mediators in the relationships between morningness-eveningness and both negative affect and positive affect. These findings suggest that metacognitive beliefs may be an important consideration in understanding the associations between morningness-eveningness and well-being.

4.Relic DNA does not obscure the microbial community of paddy soil microbial fuel cells

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


Abstract:Soil Microbial Fuel Cells (MFCs) are devices that can generate electricity by using the flooded soil's anode respiring microbial consortium. When the MFC starts to work, the microbial community in the anode vicinity rapidly changes. This shift in the microbial community results in many dead cells that may release their DNA (relic DNA) and obscure culture independent estimates of microbial community composition. Although relic DNA is expected to increase in MFCs, the effect of relic DNA has not been investigated in the soil MFCs system. In this study the effect of the MFCs on the soil microbial community composition within the soil profile and the influence of relic DNA were investigated. Microbial community analysis revealed that the MFCs deployment significantly influenced the community composition within the soil profile. The phylum Proteobacteria (34.4%% vs 23.6%%) and the class Deltaproteobacteria (16.8%% vs 5.9%%) significantly increased in the MFCs compared to the control, while the phylum Firmicutes (24.0%% vs 28.7%%) and the class Sphingobacteria (5.3%% vs 7.0%%) were more abundant in the control. Furthermore, the archaeal phyla Euryarchaeota (40.7%% vs 52.3%%) and Bathyarchaeota (10.1%% vs 17.3%%) were significantly lower in the MFCs, whereas the phylum Woesearchaeota (DHVEG6) (24.4%% vs 19.4%%) was slightly enhanced. Moreover, the results showed that relic DNA can affect the relative abundance of Geobacter and Candidatus Methanoperedens, however, it has no significant effects on the microbial community structure. These results indicate that MFCs can influence the soil microbial community profile, nevertheless the relic DNA generated has minimum effect on the culture independent estimates of microbial community composition. (C) 2018 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

5.Clinical Validity and Reliability of the Malay Language Translations of Gastroesophageal Reflux Disease Questionnaire and Quality of Life in Reflux and Dyspepsia Questionnaire in a Primary Care Setting

Author:Vadivelu, S;Ma, ZF;Ong, EW;Hassan, N;Hassan, NFHN;Aziz, SHSA;Kueh, YC;Lee, YY


Abstract:Background: Gastroesophageal Reflux Disease Questionnaire (GERDQ) and Quality of Life in Reflux and Dyspepsia Questionnaire (QOLRAD) are reliable tools for evaluation of GERD. Aim: We aimed to test validity and reliability of Malay language translations of GERDQ and QOLRAD in a primary care setting. Methods: The questionnaires were first translated into the Malay language (GERDQ-M and QOLRAD-M). Patients from primary care clinics with suspected GERD were recruited to complete GERDQ-M, QOLRAD-M, and Malay-translated 36-item short-form health survey (SF-36 or SF36-M), and underwent endoscopy and 24-h pH-impedance test. Results: A total of 104 (mean age 47.1 years, women 51.9%%) participants were enrolled. The sensitivity and specificity for GERDQ-M cut-off score >= 8 were 90.2 and 77.4%%, respectively. Based on this cut-off score, 54.7%% had a high probability of GERD diagnosis. GERD-M score >= 8 vs. <8 was associated with erosive esophagitis (p < 0.001), hiatus hernia (p = 0.03), greater DeMeester score (p = 0.001), and Zerbib scores for acid refluxes (p < 0.001) but not non-acid refluxes (p = 0.1). Mean total scores of QOLRAD-M and SF-36-M were correlated (r = 0.74, p < 0.001). GERDQ-M = 8, erosive esophagitis, and DeMeester >= 14.72 were associated with impaired QOLRAD-M in all domains (all p < 0.02) but this was not seen with SF-36. Conclusions: GERDQ-M and QOLRAD-M are valid and reliable tools applicable in a primary care setting. (C) 2018 S. Karger AG, Basel

6.The effects of the bioanode on the microbial community and element profile in paddy soil

Author:Williamson, G;Chen, Z


Abstract:In paddy soil the reductive dissolution of iron oxide and the availability of organic matter plays an important role in arsenic release under anaerobic conditions. Microbial fuel cells have been shown to reduce organic matter (OM) content and the rate in which this occurs strongly relate to the external resistance applied. In this study we investigated the effects of bioanode operating at different external resistance on the paddy soil microbial community and iron and arsenic concentration. The results show that MFC can be used to reduce soil pore water iron and arsenic concentration and the extent in which this occurs depend on the external resistance applied. The MFC is able to mitigate arsenic release by decreasing organic matter availability. Furthermore, our finding shows that external resistance had a significant influence on the bacterial community composition that develop on the bioanode however only had minimal effect on the community of the bulk soil. These findings suggest that the sMFC can influence the iron and arsenic concentration by reducing OM content and the microbial community that develop in the bioanode vicinity.

7.Macroinvertebrate drift-benthos trends in a regulated river

Author:Tonkin, JD;Death, RG


Abstract:Downstream drift plays a fundamental role in the spatial distribution and community structure of lotic macroinvertebrates. We sampled both benthic and drifting macroinvertebrates at 15 sites, in three sections of river with varying flow alteration along the Tongariro River, New Zealand. Our objectives were to examine whether (i) benthic and drift density were linearly related throughout the river, (ii) the presence of dams affected the propensity of macroinvertebrates to drift, and (iii) drift propensity was related to benthic periphyton biomass or natural longitudinal patterns down the river. More taxa were collected from the drift than the benthos, although drift and benthic samples were generally taxonomically similar, despite some structural differences. Nonetheless, differences were evident between the major groups when assessing density and relative abundance links between the benthos and drift. The presence of dams did not affect the propensity of macroinvertebrates to drift on the whole, nor was propensity affected by periphyton biomass or distance from source. These results suggest that although altered periphyton biomass in downstream sections in the Tongariro River is altering the composition of benthic and drifting macroinvertebrates, drift propensity is unaffected. However, some deviations from linear relationships between benthic and drift density are evident suggesting these links may be taxon specific.

8.Light attenuation - a more effective basis for the management of fine suspended sediment than mass concentration?

Author:Davies-Colley, RJ;Ballantine, DJ;Elliott, SH;Swales, A;Hughes, AO;Gall, MP


Abstract:Fine sediment continues to be a major diffuse pollution concern with its multiple effects on aquatic ecosystems. Mass concentrations (and loads) of fine sediment are usually measured and modelled, apparently with the assumption that environmental effects of sediment are predictable from mass concentrations. However, some severe impacts of fine sediment may not correlate well with mass concentration, notably those related to light attenuation by suspended particles. Light attenuation per unit mass concentration of suspended particulate matter in waters varies widely with particle size, shape and composition. Data for suspended sediment concentration, turbidity and visual clarity (which is inversely proportional to light beam attenuation) from 77 diverse New Zealand rivers provide valuable insights into the mutual relationships of these quantities. Our analysis of these relationships, both across multiple rivers and within individual rivers, supports the proposition that light attenuation by fine sediment is a more generally meaningful basis for environmental management than sediment mass. Furthermore, optical measurements are considerably more practical, being much cheaper (by about four-fold) to measure than mass concentrations, and amenable to continuous measurement. Mass concentration can be estimated with sufficient precision for many purposes from optical surrogates locally calibrated for particular rivers.

9.Nitrogen addition increases sexual reproduction and improves seedling growth in the perennial rhizomatous grass Leymus chinensis

Author:Gao, S;Wang, JF;Knops, JMH;Wang, J

Source:BMC PLANT BIOLOGY,2020,Vol.20

Abstract:Background: The Eurasian steppe is an important vegetation type characterized by cold, arid and nitrogen poor conditions. At the Eastern edge, including in the Songnen grassland, the vegetation is dominated by Leymus chinensis (henceforth L. chinensis) and is increasing threatened by elevated anthropogenic nitrogen deposition. L. chinensis is a perennial grass that mainly reproduces vegetatively and its sexual reproduction is limited. However, sexual reproduction plays an important role influencing colonization after large disturbances. To develop an understanding of how elevated nitrogen deposition changes the plant community structure and functioning we need a better understanding how sexual reproduction of L. chinensis changes with nitrogen enrichment. Here we report on a field experiment where we added 10 g N m(-2) yr(-1) and examined changes in seed traits, seed germination and early seedling growth. Results: Nitrogen addition increased seed production by 79%%, contributing to this seed increases were a 28%% increase in flowering plant density, a 40%% increase in seed number per plant and a 11%% increase in seed weight. Seed size increased with a 42%% increase in large seeds and a 49%% decrease in the smallest seed size category. Seed germination success improved by 10%% for small seeds and 18%% for large seeds. Combined, the increased in seed production and improved seed quality doubled the potential seed germination. Subsequent seedling above and below-ground biomass also significantly increased. Conclusions: All aspects of L. chinensis sexual reproduction increased with nitrogen addition. Thus, L. chinensis competitive ability may increase when atmospheric nitrogen deposition increases, which may further reduce overall plant diversity in the low diversity Songnen grasslands.

10.Supernatural Explanatory Models of Health and Illness and HIV Antiretroviral Therapy Use Among Young Men Who Have Sex with Men in China

Author:Pan, SW;Smith, MK;Carpiano, RM;Fu, HY;Ong, JJ;Huang, WT;Tang, WM;Tucker, JD


Abstract:Background In China, men who have sex with men (MSM) shoulder a disproportionate HIV burden. Early initiation and adherence to HIV antiretroviral therapy (ART) will be critical to reversing the HIV epidemic in China, but ART usage remains suboptimal among MSM diagnosed with HIV. One understudied but potentially important factor underpinning suboptimal ART usage is personal belief in supernatural explanatory models of health and illness (supernatural explanatory models). This study examines associations between beliefs in supernatural explanatory models and ART usage among MSM in China. Method In 2017, an online survey was distributed nationwide throughout China by gay community-based organizations. Eligible study participants were self-identified MSM between 16 and 30 years old who had tested positive for HIV and who had seen a doctor in the last 2 years. Beliefs in supernatural explanatory models were measured using a three-item scale developed specifically for the Chinese population (range, 3-15). Results Of 73 participants, the majority were currently using ART (83.6%%) and 42.5%% expressed some endorsement of belief in supernatural explanatory models. However, among 21 participants with the strongest belief in supernatural explanatory models, prevalence of current ART usage was 61.9%%. Stronger belief in supernatural explanatory models was significantly associated with lower likelihood of current ART usage (adjusted odds ratio = 0.52; 95%% confidence interval = 0.13-0.75). Conclusion Belief in supernatural explanatory models may be a powerful predictor of ART usage among MSM living with HIV in China. Further studies are needed to corroborate these findings and elucidate mechanisms of association.

11.Elevated serum uric acid, hyperuricaemia and dietary patterns among adolescents in mainland China

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


Abstract:Background: Elevated serum uric acid concentrations have been associated with metabolic syndrome. However, only limited information is available on the prevalence of hyperuricaemia in adolescents. Therefore, the aim of our cross-sectional study was to study the prevalence of hyperuricaemia and dietary patterns in adolescents aged 13-16 years living in Yangzhou, China. Methods: Adolescents were asked to complete a 20-item food frequency questionnaire (FFQ) and provide an overnight fasting finger-prick sample. Principal component analysis (PCA) with varimax rotation was used to derive the dietary patterns that might be associated with high uric acid concentrations. Results: A total of 1070 adolescents were recruited. Of these, 53.6%% (n = 574) were females, and 58.5%% (n = 625) were within the normal body mass index (BMI) range. The males had a significantly higher serving size and frequency in their weekly food consumption, including meat, poultry, Chinese cereal staple foods and Western-style fast foods, than the females (all p < 0.02). The overall mean serum uric acid concentration and prevalence of hyperuricaemia were 368.6 +/- 114.5 mu mol/L and 37.9%%, respectively. The prevalence of hyperuricaemia was 4.633 times greater among the participants who were overweight and obese than among those who were underweight. On the other hand, the prevalence of hyperuricaemia was 0.694 times lower among the participants who had normal weight than those who were underweight. Conclusions: The prevalence of hyperuricaemia was relatively high in Chinese adolescents. The prevention of hyperuricaemia measures should be strengthened in adolescents to effectively control for obesity and gout, which tend to persist into adulthood.

12.High Baseline CD4 Counts and Antiretroviral Therapy Cessation

Author:Pan, SW;Shen, ZY;Xing, H;Ruan, YH;Shao, YM


13.Goji Berries as a Potential Natural Antioxidant Medicine: An Insight into Their Molecular Mechanisms of Action

Author:Ma, ZF;Zhang, HX;Teh, SS;Wang, CW;Zhang, YT;Hayford, F;Wang, LY;Ma, T;Dong, ZH;Zhang, Y;Zhu, YF


Abstract:Goji berries (Lycium fruits) are usually found in Asia, particularly in northwest regions of China. Traditionally, dried goji berries are cooked before they are consumed. They are commonly used in Chinese soups and as herbal tea. Moreover, goji berries are used for the production of tincture, wine, and juice. Goji berries are high antioxidant potential fruits which alleviate oxidative stress to confer many health protective benefits such as preventing free radicals from damaging DNA, lipids, and proteins. Therefore, the aim of the review was to focus on the bioactive compounds and pharmacological properties of goji berries including their molecular mechanisms of action. The health benefits of goji berries include enhancing hemopoiesis, antiradiation, antiaging, anticancer, improvement of immunity, and antioxidation. There is a better protection through synergistic and additive effects in fruits and herbal products from a complex mixture of phytochemicals when compared to one single phytochemical.

14.Landscape effects on pollinator communities and pollination services in small-holder agroecosystems

Author:Zou, Y;Bianchi, FJJA;Jauker, F;Xiao, HJ;Chen, JH;Cresswell, J;Luo, SD;Huang, JK;Deng, XZ;Hou, LL;van der Werf, W


Abstract:Pollination by insects is key for the productivity of many fruit and non-graminous seed crops, but little is known about the response of pollinators to landscapes dominated by small-holder agriculture. Here we assess the relationships between landscape context, pollinator communities (density and diversity) and pollination of oilseed rape in 18 landscapes with proportions of small-holder farming ranging from 10%% to 70%% in southern China. To quantify the contribution of pollinators to oilseed rape yield, we manipulated pollinator access in a focal oilseed rape field in each landscape using open and closed cages. The pollinator communities in the focal fields were sampled using pan traps. The abundance of wild pollinators increased significantly with the proportion of cultivated land, but the diversity of the wild pollinator communities declined. The responses of pollinator abundance and diversity to cultivated land were best explained at scales of around 1000 m. The abundance of the unmanaged honey bee Apis cerana was positively associated with the proportion of cultivated land, whereas the abundance of the managed A. mellifera was not. A pollination services index (PSI) was calculated by comparing the reproductive investment in seeds between plants with or without pollinator access. PSI was positively correlated with wild pollinator abundance, but not with the abundance of honeybee species. PSI was also not significantly correlated with the area proportion of cultivated land. Our results indicate that crop dominated landscapes with numerous small fields supported an abundant, but relatively species poor bee community that delivered pollination services to oilseed rape. Conservation of (semi-)natural habitats, however, is important for maintaining the diversity of wild pollinators.

15.Environmental context for late Holocene human occupation of the South Wellesley Archipelago, Gulf of Carpentaria, northern Australia

Author:Moss, P;Mackenzie, L;Ulm, S;Sloss, C;Rosendahl, D;Petherick, L;Steinberger, L;Wallis, L;Heijnis, H;Petchey, F;Jacobsen, G


Abstract:A 2400 year record of environmental change is reported from a wetland on Bentinck Island in the southern Gulf of Carpentaria, northern Australia. Three phases of wetland development are identified, with a protected coastal setting from ca. 2400 to 500 years ago, transitioning into an estuarine mangrove forest from ca. 500 years ago to the 1940s, and finally to a freshwater swamp over the past +60 years. This sequence reflects the influence of falling sea-levels, development of a coastal dune barrier system, prograding shorelines, and an extreme storm (cyclone) event. In addition, there is clear evidence of the impacts that human abandonment and resettlement have on the island's fire regimes and vegetation. A dramatic increase in burning and vegetation thickening was observed after the cessation of traditional Indigenous Kaiadilt fire management practices in the 1940s, and was then reversed when people returned to the island in the 1980s. In terms of the longer context for human occupation of the South Wellesley Archipelago, it is apparent that the mangrove phase provided a stable and productive environment that was conducive for human settlement of this region over the past 1000 years. (C) 2015 Elsevier Ltd and INQUA. All rights reserved.

16.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


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.

17.Rhinophore bio-inspired stretchable and programmable electrochemical sensor

Author:Wang, SQ;Qu, CY;Liu, L;Li, LH;Li, T;Qin, SJ;Zhang, T


Abstract:Rhinophore, a bio-chemical sensory organ with soft and stretchable/retractable features in many marine molluscs species, exhibits tunable chemosensory abilities in terms of far/near-field chemical detection and molecules' source orientation. However, existing artificial bio-chemical sensors cannot provide tunable modality sensing. Inspired by the anatomical units (folded sensory epithelium) and the functions of a rhinophore, this work introduces a stretchable electrochemical sensor that offers a programmable electro-catalytic performance towards glucose based on the fold/unfold regulation of the gold nanomembrane on an elastic fiber. Geometrical design rationale and covalent bonding strategy are used to realize the robust mechanical and electrical stability of this stretchable bionic sensor. Electrochemical tests demonstrated that the sensitivities of the as-prepared bionic sensor exhibit a linear relationship with its strain states from 0%% to 150%%. Bio-inspired sensory functions are tested by regulating the strain of the bionic sensor. The sensor achieves a sensitivity of 195.4 mu A mM(-1) in a low glucose concentration range of 8-206 mu M at 150%% strain for potentially far-field chemical detection, and a sensitivity of 14.2 mu A mM(-1) in a high concentration range of 10-100 mM at 0%% strain for near-field chemical detection. Moreover, the bionic sensor performs the detection while extending its length can largely enhance the response signal, which is used to distinguish the molecules' source direction. This proposed bionic sensor can be useful in wearable devices, robotics and bionics applications which require diverse modality sensing and smart chemical tracking system.

18.Trait dependent roles of environmental factors, spatial processes and grazing pressure on lake phytoplankton metacommunity

Author:Guo, K;Wu, NC;Wang, C;Yang, DG;He, YF;Luo, JB;Chai, Y;Duan, M;Huang, XF;Riis, T


Abstract:Using metacommunity theory to understand the mechanisms shaping community structure is a promising framework that has been widely applied to ecological research. In lakes, the spatial pattern of phytoplankton assemblages depends on the relative importance of environmental conditions, spatial processes, and biotic interactions (e.g., grazing pressure), but the inclusion of the latter two factors was often overlooked. We tested how these three factors contributed to phytoplankton community composition in a shallow lake by separating the responses of taxonomic and trait compositions (i.e., nine species traits groups) of phytoplankton in Lake Changhu, China. Our results indicated that the taxonomic composition of phytoplankton assemblages in Lake Changhu are mainly determined by environmental factors (7.6 +/- 1.3%%), followed by spatial processes (4.7 +/- 1.0%%) and grazing pressure (2.9 +/- 0.5%%). However, for the nine species traits groups, relative influences of environmental, spatial and grazing factors were trait specific, suggesting that different mechanisms were responsible for community composition supporting the potential advantages of using traits in water quality assessment. More specifically, some traits (e.g., large cell size and filamentous) may be excellent candidates for biomonitoring in lakes as they are predominantly driven by environmental factors (12.4%% and 17.2%% for large cell size and filamentous respectively), while other traits (e.g., unicellular and non-motile) are controlled largely by spatial processes or grazing and may not be suitable as bio-indicators. We also advocate inclusion of biotic factors (e.g., grazing pressure) in community studies, since we have found relatively weak but unneglectable effects of grazing on structuring phytoplankton community (2.9 +/- 0.5%% for taxonomic composition while 3.1 +/- 4.1%% for trait composition). In general, our findings suggest that a combination of metacommunity theory and the use of traits provide a useful framework for assessing driving factors structuring phytoplankton community in lakes, and such framework can be very useful for future lake bioassessment and management efforts.

19.The Chord-Normalized Expected Species Shared (CNESS)-distance represents a superior measure of species turnover patterns

Author:Zou, Y;Axmacher, JC


Abstract:Measures of beta-diversity characterizing the difference in species composition between samples are commonly used in ecological studies. Nonetheless, commonly used dissimilarity measures require high sample completeness, or at least similar sample sizes between samples. In contrast, the Chord-Normalized Expected Species Shared (CNESS) dissimilarity measure calculates the probability of collecting the same set of species in random samples of a standardized size, and hence is not sensitive to completeness or size of compared samples. To date, this index has enjoyed limited use due to difficulties in its calculation and scarcity of studies systematically comparing it with other measures. Here, we developed a novel R function that enables users to calculate ESS (Expected Species Shared)-associated measures. We evaluated the performance of the CNESS index based on simulated datasets of known species distribution structure, and compared CNESS with more widespread dissimilarity measures (Bray-Curtis index, Chao-Sorensen index, and proportionality-based Euclidean distances) for varying sample completeness and sample sizes. Simulation results indicated that for small sample size (m) values, CNESS chiefly reflects similarities in dominant species, while selecting large m values emphasizes differences in the overall species assemblages. Permutation tests revealed that CNESS has a consistently low CV (coefficient of variation) even where sample completeness varies, while the Chao-Sorensen index has a high CV particularly for low sampling completeness. CNESS distances are also more robust than other indices with regards to undersampling, particularly when chiefly rare species are shared between two assemblages. Our results emphasize the superiority of CNESS for comparisons of samples diverging in sample completeness and size, which is particularly important in studies of highly mobile and species-rich taxa where sample completeness is often low. Via changes in the sample size parameter m, CNESS furthermore cannot only provide insights into the similarity of the overall distribution structure of shared species, but also into the differences in dominant and rare species, hence allowing additional, valuable insights beyond the capability of more widespread measures.

20.Designing an Optimized Water Quality Monitoring Network with Reserved Monitoring Locations

Author:Zhu, XH;Yue, Y;Wong, PWH;Zhang, YX;Ding, H


Abstract:The optimized design of water quality monitoring networks can not only minimize the pollution detection time and maximize the detection probability for river systems but also reduce redundant monitoring locations. In addition, it can save investments and costs for building and operating monitoring systems as well as satisfy management requirements. This paper aims to use the beneficial features of multi-objective discrete particle swarm optimization (MODPSO) to optimize the design of water quality monitoring networks. Four optimization objectives: minimum pollution detection time, maximum pollution detection probability, maximum centrality of monitoring locations and reservation of particular monitoring locations, are proposed. To guide the convergence process and keep reserved monitoring locations in the Pareto frontier, we use a binary matrix to denote reserved monitoring locations and develop a new particle initialization procedure as well as discrete functions for updating particle's velocity and position. The storm water management model (SWMM) is used to model a hypothetical river network which was studied in the literature for comparative analysis of our work. We define three pollution detection thresholds and simulate pollution events respectively to obtain all the pollution detection time for all the potential monitoring locations when a pollution event occurs randomly at any potential monitoring locations. Compared to the results of an enumeration search method, we confirm that our algorithm could obtain the Pareto frontier of optimized monitoring network design, and the reserved monitoring locations are included to satisfy the management requirements. This paper makes fundamental advancements of MODPSO and enables it to optimize the design of water quality monitoring networks with reserved monitoring locations.

21.Crop pests and predators exhibit inconsistent responses to surrounding landscape composition

Author:Karp, DS;Chaplin-Kramer, R;Meehan, TD;Martin, EA;DeClerck, F;Grab, H;Gratton, C;Hunt, L;Larsen, AE;Martinez-Salinas, A;O'Rourke, ME;Rusch, A;Poveda, K;Jonsson, M;Rosenheim, JA;Schellhorn, NA;Tscharntke, T;Wratten, SD;Zhang, W;Iverson, AL;Adler, LS;Albrecht, M;Alignier, A;Angelella, GM;Anjum, MZ;Avelino, J;Batary, P;Baveco, JM;Bianchi, FJJA;Birkhofer, K;Bohnenblust, EW;Bommarco, R;Brewer, MJ;Caballero-Lopez, B;Carriere, Y;Carvalheiro, LG;Cayuela, L;Centrella, M;Cetkovic, A;Henri, DC;Chabert, A;Costamagna, AC;De la Mora, A;de Kraker, J;Desneux, N;Diehl, E;Diekotter, T;Dormann, CF;Eckberg, JO;Entling, MH;Fiedler, D;Franck, P;van Veen, FJF;Frank, T;Gagic, V;Garratt, MPD;Getachew, A;Gonthier, DJ;Goodell, PB;Graziosi, I;Groves, RL;Gurr, GM;Hajian-Forooshani, Z;Heimpel, GE;Herrmann, JD;Huseth, AS;Inclan, DJ;Ingrao, AJ;Iv, P;Jacot, K;Johnson, GA;Jones, L;Kaiser, M;Kaser, JM;Keasar, T;Kim, TN;Kishinevsky, M;Landis, DA;Lavandero, B;Lavigne, C;Le Ralec, A;Lemessa, D;Letourneau, DK;Liere, H;Lu, YH;Lubin, Y;Luttermoser, T;Maas, B;Mace, K;Madeira, F;Mader, V;Cortesero, AM;Marini, L;Martinez, E;Martinson, HM;Menozzi, P;Mitchell, MGE;Miyashita, T;Molina, GAR;Molina-Montenegro, MA;O'Neal, ME;Opatovsky, I;Ortiz-Martinez, S;Nash, M;Ostman, O;Ouin, A;Pak, D;Paredes, D;Parsa, S;Parry, H;Perez-Alvarez, R;Perovic, DJ;Peterson, JA;Petit, S;Philpott, SM;Plantegenest, M;Plecas, M;Pluess, T;Pons, X;Potts, SG;Pywell, RF;Ragsdale, DW;Rand, TA;Raymond, L;Ricci, B;Sargent, C;Sarthou, JP;Saulais, J;Schackermann, J;Schmidt, NP;Schneider, G;Schuepp, C;Sivakoff, FS;Smith, HG;Whitney, KS;Stutz, S;Szendrei, Z;Takada, MB;Taki, H;Tamburini, G;Thomson, LJ;Tricault, Y;Tsafack, N;Tschumi, M;Valantin-Morison, M;Trinh, MV;van der Werf, W;Vierling, KT;Werling, BP;Wickens, JB;Wickens, VJ;Woodcock, BA;Wyckhuys, K;Xiao, HJ;Yasuda, M;Yoshioka, A;Zou, Y


Abstract:The idea that noncrop habitat enhances pest control and represents a win-win opportunity to conserve biodiversity and bolster yields has emerged as an agroecological paradigm. However, while noncrop habitat in landscapes surrounding farms sometimes benefits pest predators, natural enemy responses remain heterogeneous across studies and effects on pests are inconclusive. The observed heterogeneity in species responses to noncrop habitat may be biological in origin or could result from variation in how habitat and biocontrol are measured. Here, we use a pest-control database encompassing 132 studies and 6,759 sites worldwide to model natural enemy and pest abundances, predation rates, and crop damage as a function of landscape composition. Our results showed that although landscape composition explained significant variation within studies, pest and enemy abundances, predation rates, crop damage, and yields each exhibited different responses across studies, sometimes increasing and sometimes decreasing in landscapes with more noncrop habitat but overall showing no consistent trend. Thus, models that used landscape-composition variables to predict pest-control dynamics demonstrated little potential to explain variation across studies, though prediction did improve when comparing studies with similar crop and landscape features. Overall, our work shows that surrounding noncrop habitat does not consistently improve pest management, meaning habitat conservation may bolster production in some systems and depress yields in others. Future efforts to develop tools that inform farmers when habitat conservation truly represents a win-win would benefit from increased understanding of how landscape effects are modulated by local farm management and the biology of pests and their enemies.

22.Nutrient availability controls the impact of mammalian herbivores on soil carbon and nitrogen pools in grasslands

Author:Sitters, J;Wubs, ERJ;Bakker, ES;Crowther, TW;Adler, PB;Bagchi, S;Bakker, JD;Biederman, L;Borer, ET;Cleland, EE;Eisenhauer, N;Firn, J;Gherardi, L;Hagenah, N;Hautier, Y;Hobbie, SE;Knops, JMH;MacDougall, AS;McCulley, RL;Moore, JL;Mortensen, B;Peri, PL;Prober, SM;Riggs, C;Risch, AC;Schutz, M;Seabloom, EW;Siebert, J;Stevens, CJ;Veen, GF


Abstract:Grasslands are subject to considerable alteration due to human activities globally, including widespread changes in populations and composition of large mammalian herbivores and elevated supply of nutrients. Grassland soils remain important reservoirs of carbon (C) and nitrogen (N). Herbivores may affect both C and N pools and these changes likely interact with increases in soil nutrient availability. Given the scale of grassland soil fluxes, such changes can have striking consequences for atmospheric C concentrations and the climate. Here, we use the Nutrient Network experiment to examine the responses of soil C and N pools to mammalian herbivore exclusion across 22 grasslands, under ambient and elevated nutrient availabilities (fertilized with NPK + micronutrients). We show that the impact of herbivore exclusion on soil C and N pools depends on fertilization. Under ambient nutrient conditions, we observed no effect of herbivore exclusion, but under elevated nutrient supply, pools are smaller upon herbivore exclusion. The highest mean soil C and N pools were found in grazed and fertilized plots. The decrease in soil C and N upon herbivore exclusion in combination with fertilization correlated with a decrease in aboveground plant biomass and microbial activity, indicating a reduced storage of organic matter and microbial residues as soil C and N. The response of soil C and N pools to herbivore exclusion was contingent on temperature - herbivores likely cause losses of C and N in colder sites and increases in warmer sites. Additionally, grasslands that contain mammalian herbivores have the potential to sequester more N under increased temperature variability and nutrient enrichment than ungrazed grasslands. Our study highlights the importance of conserving mammalian herbivore populations in grasslands worldwide. We need to incorporate local-scale herbivory, and its interaction with nutrient enrichment and climate, within global-scale models to better predict land-atmosphere interactions under future climate change.

23.Elevational species richness gradients in a hyperdiverse insect taxon: a global meta-study on geometrid moths

Author:Beck, J;McCain, CM;Axmacher, JC;Ashton, LA;Bartschi, F;Brehm, G;Choi, SW;Cizek, O;Colwell, RK;Fiedler, K;Francois, CL;Highland, S;Holloway, JD;Intachat, J;Kadlec, T;Kitching, RL;Maunsell, SC;Merckx, T;Nakamura, A;Odell, E;Sang, W;Toko, PS;Zamecnik, J;Zou, Y;Novotny, V


Abstract:Aims We aim to document elevational richness patterns of geometrid moths in a globally replicated, multi-gradient setting, and to test general hypotheses on environmental and spatial effects (i. e. productivity, temperature, precipitation, area, mid-domain effect and human habitat disturbance) on these richness patterns. Location Twenty-six elevational gradients world-wide (latitudes 288 S to 518 N). Methods We compiled field datasets on elevational gradients for geometrid moths, a lepidopteran family, and documented richness patterns across each gradient while accounting for local undersampling of richness. Environmental and spatial predictor variables as well as habitat disturbance were used to test various hypotheses. Our analyses comprised two pathways: univariate correlations within gradients, and multivariate modelling on pooled data after correcting for overall variation in richness among different gradients. Results The majority of gradients showed midpeak patterns of richness, irrespective of climate and geographical location. The exclusion of humanaffected sampling plots did not change these patterns. Support for univariate main drivers of richness was generally low, although there was idiosyncratic support for particular predictors on single gradients. Multivariate models, in agreement with univariate results, provided the strongest support for an effect of area-integrated productivity, or alternatively for an elevational area effect. Temperature and the mid-domain effect received support as weaker, modulating covariates, while precipitation-related variables had no explanatory potential. Main conclusions Despite the predicted decreasing diversity-temperature relationship in ectotherms, geometrid moths are similar to ants and salamanders as well as small mammals and ferns in having predominantly their highest diversity at mid-elevations. As in those comparative analyses, single or clear sets of drivers are elusive, but both productivity and area appear to be influential. More comparative elevational studies for various insect taxa are necessary for a more comprehensive understanding of elevational diversity and productivity.



Source:China Scholars Abroad,2017,Vol.


25.Effects of particulate matter (PM2.5) and associated acidity on ecosystem functioning: response of leaf litter breakdown

Author:Wu, WT;Zhang, YX


Abstract:Particulate matter (PM2.5 with the diameter2.5m) as one of the most harmful and complex pollutants can reduce environment quality and affect human health. Through acidification by wet deposition, PM2.5 can cause acid rain to impact aquatic ecosystems. However, our understanding of PM2.5 effect on ecosystem functioning is highly limited. This study investigated the relationship between PM2.5 concentration, associated acidity, and leaf litter breakdown of three tree species in laboratory experimental mesocosms, which are weeping willow (Salix babylonica), camphor tree(Cinnamomum camphora), and the south magnolia (Magnolia grandiflora). We found that leaf litter breakdown was significant affected by PM2.5 and associated acidity. With the increase of acidity, the leaf breakdown rate of all three tree species decreased. With the increase of PM2.5 concentration, the leaf breakdown rates of those leaves slowed down. When considering the influence of leaf toughness, willow leaves with lower toughness had a higher breakdown rate than that of camphor tree and the south magnolia. Our study suggests that PM2.5 has significant impact on the aquatic ecosystem functioning through increasing acidification in aquatic environment. Hence, along with ecological restoration of local aquatic habitats, further freshwater ecosystem management should include reducing air pollution through regional efforts of best ecosystem management.

26.MSM Behavior Disclosure Networks and HIV Testing: An Egocentric Network Analysis Among MSM in China

Author:Cao, BL;Saffer, AJ;Yang, C;Chen, HX;Peng, K;Pan, SW;Durvasula, M;Liu, CC;Fu, HY;Ong, JJ;Tang, WM;Tucker, JD

Source:AIDS AND BEHAVIOR,2019,Vol.23

Abstract:Men who have sex with men (MSM) disclose same-sex behaviors with others, creating disclosure networks. This study examined the characteristics of disclosure networks that are associated with HIV testing among MSM in China through an online nationwide survey. Name-generator questions were used to ask each participant ("ego") to nominate up to five social network members ("alters") with whom he had disclosed same-sex behaviors. Among the 806 men, the average disclosure network size was 4.05. MSM who reported larger disclosure networks were more likely to have been tested for HIV (aOR 1.21, 95%% CI 1.08-1.34). The most common disclosure network alters were friends (45.1%%), followed by sex partners (18.7%%) and healthcare professionals (2.5%%). Men who disclosed to healthcare professionals were more likely to test for HIV compared to men who disclosed to family members (aOR 5.43, 95%% CI 2.11-14.04). Our findings can inform disclosure network-based interventions to promote MSM HIV testing.

27.Larger Seed Size Shows Less Germination and Seedling Growth Decline Caused by Seed Ageing under Na2CO3 Stress in Leymus chinensis

Author:Ao, YN;Wang, JF;Liu, MX;Wang, J;Knops, JMH;Mu, CS

Source:AGRONOMY JOURNAL,2019,Vol.111

Abstract:Understanding of seed germination in sodic soils is needed to accelerate the restoration process in degraded saline-sodic grassland. The objective of this study was to determine the influence of seed age (2 vs. 6 yr) and seed size (small vs. large) on seed germination and seedling growth in sodic grasslands. Older seeds (6 vs. 2 yr) reduced seed germination by 29%%, germination potential by 36%%, and the seedling vigor index by 52%%. Seed size (small vs. large) reduced seed germination by 18%%, germination potential by 20%%, and seedling vigor by 19%%. Sodic salt stress (>10 mM Na2CO3) decreased germination by 64%%, germination potential by 68%%, and seedling vigor index by 33%%. Sodic salt stress decreases in seed germination and seedling vigor increased with seed age. These findings suggest that younger and large seeds are preferable for restoration efforts in sodic soils. Thus, in regions where the soil has a high level of sodicity, we suggest that large seeds be selected and stored only for a short period of time for seeding.

28.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.

29.Out of the Closet, Into the Clinic: Opportunities for Expanding Men Who Have Sex With Men-Competent Services in China

Author:Watson, J;Tang, WM;Pan, S;Wu, D;Zhao, PP;Cao, BL;Liu, CC;Bien, C;Huang, WT;Luo, ZZ;Tucker, JD


Abstract:Background Despite the high human immunodeficiency virus (HIV) burden among men who have sex with men (MSM), there is little research on health services provided to MSM in China and other low- and middle-income countries. Discrimination and inadequate services may discourage MSM from seeking health care services. This study examined essential services provided to MSM and health care discrimination among MSM in China. Methods A nationwide cross-sectional online survey was conducted among MSM who saw a physician in the last 24 months in China. The survey included items on sociodemographic information, HIV testing, experiences from the last physician encounter, and history of perceived health care discrimination. We defined MSM-competent physicians as physicians who asked their patient about having sex with other men, asked about anal sex, and either asked about or recommended HIV testing at the most recent visit. Results Among the 503 participants, 35.0%% (176/503) saw an MSM-competent physician. In multivariate analyses, respondents who saw an MSM-competent physician were more likely to be younger (adjusted odds ratio [AOR], 0.87; 95%% confidence interval [CI], 0.81-0.94), have a primary care physician (AOR, 3.24; 95%% CI, 1.85-5.67), and be living with HIV (AOR, 2.01; 95%% CI, 1.13-3.56). 61.2%% (308/503) of MSM had ever experienced health care discrimination. Conclusions Our data suggest that there is variability in the extent to which physicians are meeting the needs of MSM in China. There is an urgent need to evaluate and expand MSM-competent services in China.

30.Bridging the HIV-syphilis testing gap: dual testing among men who have sex with men living in China

Author:Ong, JJ;Liao, MZ;Lee, A;Fu, HY;Pan, SW;Tang, WM;Wei, CY;Dan, W;Yang, B;Yang, LG;Wang, C;Tucker, JD


Abstract:Objectives T he WHO recommends dual testing for HIV and syphilis among key populations, including men who have sex with men (MSM). We assessed the proportion of men who had dual tested and reasons for not dual testing. Methods In 2017, an online survey of MSM was conducted in eight cities from two provinces in China. Data on sociodemographics and sexual behaviours were collected. Descriptive analysis was used to examine the experience of dual testing. Multivariable logistic regression identified characteristics associated with men who had dual tested. Results Among 802 men who had ever tested for HIV, 297 dual tested (37%%, 95%% CI 34 to 40). Men dual tested in a variety of settings: public hospital (35%%), voluntary counselling and testing sites (28%%), selftesting at home (18%%), community- based organisation (8%%), community health centre (7%%), other (3%%) or private hospital (1%%). Greater odds for dual testing was found in men who had disclosed their sexuality to a healthcare provider (adjusted OR (AOR) 1.81, 95%% CI 1.27 to 2.59, p=0.001), and who had substantial (AOR 2.71, 95%% CI 1.67 to 4.41, p0.001) or moderate community engagement in sexual health (AOR 2.30, 95%% CI 1.49 to 3.57, p0.001), compared with those with no community engagement. The most common reasons for not dual testing were no knowledge that they could be dual tested (34%%), did not ask the doctor to be dual tested (25%%) and did not believe they were at risk for syphilis (19%%). Conclusions Chinese MSM are dual testing through a variety of test sites, including home self- testing. However, the overall dual testing rate remains low despite recent efforts to integrate HIV and syphilis testing.

31.The change in biotic and abiotic soil components influenced by paddy soil microbial fuel cells loaded with various resistances

Author:Gustave, W;Yuan, ZF;Sekar, R;Ren, YX;Chang, HC;Liu, JJY;Chen, Z


Abstract:PurposeSoil microbial fuel cells (sMFC) are novel technique that uses organic matters in soils as an alternative energy source. External resistance (ER) is a key factor that influences sMFC performance and also alters the soil biological and chemical reactions. However, little information is available on how the microbial community and soil component changes in sMFC with different ER. Thus, the purpose of this study is to collectively examine the effects of different ER on paddy soil biotic and abiotic components.Materials and methodsEighteen paddy sMFC were constructed and operated at five different ER (2000, 1000, 200, 80, and 50) in triplicates for 90days. The effects of the sMFC anodes at different ER were examined by measuring organic matter (OM) removal efficiency, trace elements in porewater, and bacterial community structure in contaminated paddy soil.Results and discussionThe results indicate that ER has significant effects on sMFC power production, OM removal efficiency, and bacterial beta diversity. Moreover, ER influences iron, arsenic, and nickel concentration as well in soil porewater. In particular, greater current densities were observed at lower ER (2.6mA, 50) as compared to a higher ER (0.3mA, 2000). The removal efficiency of OM increased with decreasing ER, whereas it decreased with soil distance away from the anode. Furthermore, principal coordinate analysis (PCoA) revealed that ER may shape the bacterial community that develop in the anode vicinity but have minimal effect on that of the bulk soil.ConclusionsThe current study illustrates that lower ER can be used to selectively enhance the relative abundance of electrogenic bacteria and lead to high OM removal.

32.Local environmental, geo-climatic and spatial factors interact to drive community distributions and diversity patterns of stream benthic algae, macroinvertebrates and fishes in a large basin, Northeast China

Author:Zhou, SC;Wu, NC;Zhang, M;Peng, WQ;He, FZ;Guo, K;Yan, SY;Zou, Y;Qu, XD


Abstract:Understanding processes and mechanisms driving patterns of species distribution and diversity is a vital theme in community ecology and conservation biology. There has been a continuous increase in studies focusing on diversity patterns in freshwater ecosystems during the last few decades. However, comparative studies of species distributions, diversity patterns and underlying processes across trophic levels remain limited. The unique characteristics of the study area (i.e. Hun-Tai River in Northeast China) generates a wide range of environmental conditions to advance our understanding of what drives community assembly and diversity pattern of three stream organism groups. We applied variance partitioning (VPA) to correlate community compositions with environmental and spatial factors to infer stochastic and deterministic assembly processes, respectively. Linear regression (LR) models were used to identify the main drivers of species richness and local contributions to beta diversity (LCBD) as a function of different factors, including local environmental (e.g., in situ parameters, hydrology, nutrients), geo-climatic variables (e.g., land use, topography, climate) and spatial factors. Results indicated that species compositions of stream biota showed significant correlations with local environmental, geoclimatic and spatial factors. VPA demonstrated that both paradigms (i.e. deterministic and stochastic processes) interact to influence the biota distributions with stochastic process contributing more than deterministic process. In addition, the strongest stochastic process was found in fishes (10%%), followed by benthic algae and macroinvertebrates with the same effects (8%%). Notably, geo-climatic factors explained a substantial fraction of species composition, richness and beta diversity, although their effects were partially manifested via local and spatial variables. We demonstrate the relative importance of both stochastic and deterministic processes in shaping community composition and biodiversity of three stream organism groups in a large basin. This emphasizes the need to move beyond observed patterns and consider metacommunity theory into river management and conservation practices.

33.Spatial Variation of Urban Thermal Environment and Its Relation to Green Space Patterns: Implication to Sustainable Landscape Planning

Author:Wu, ZJ;Zhang, YX


Abstract:The rapid changes of land covers in urban areas are one of major environmental concerns because of their environmental impacts. Such land cover changes include the transformation of green space to impervious surface, and the increase of land surface temperature (LST). The objective of this study was to examine the spatial variation of urban landscape composition and configuration, as well as their influences on LST in Suzhou City, China. Landsat-8 image was processed to extract land covers and retrieve LSTs that were used to study relationship between spatial variation of LST and land covers. The results indicated that there was a significantly negative correlation between mean LST and green space coverage along the urban-rural gradients. With every 10%% increased green space coverage, the mean LST drop was about 1.41 degrees C. A grid-base analysis performed at various grid sizes indicated that an increase in the percentage of surface water body area has a greater cooling effect of the mean LST than a vegetation increase. The mean LST had a significantly negative correlation with both the shape and aggregation indexes of the green space patches. Our results suggest that the sustainable landscape planning of green space in a typical city with a large water area should include both the vegetation and the surface water covers. The increased percentage of vegetation and surface water covers had the greatest cooling effect on an urban thermal environment, which is one of the ecosystem services that green space provides. A dense distribution of green space patches with complex shapes should be considered in urban sustainable landscape planning for increasing ecosystem services.


Author:陈正;Gustave Williams;



35.Progress of Research on Aeolian Sediment Transport Influenced by Tide

Author:He Yanyu;Liu Jianhui;Cai Feng;Li Bailiang;Wang Lihui;Ning Qingqian

Source:Journal of Desert Research,2018,Vol.38

Abstract:Alternate wetting and drying beachface induced by tide is one of the most important process influencing beach aeolian sediment transport.From the aspects of temporal and spatial variabilities of surface moisture content and cyclical variation of wind fetch length,as well as their own effect on beach aeolian sediment transport in the environment of alternate wetting and drying induced by tide,this paper summarizes the main progress and achievements of beach aeolian sediment transport influenced by tide.The main conclusions of this review are shown as:(1)The relationship between surface moisture variabilities and tidal oscillation is nonlinear,which is separated by a double hysteresis effect induced by watertable and capillary fringe;(2)A positive correlation between aeolian sediment transport threshold and surface moisture has been found in the case of surface moisture less than critical moisture threshold and the beach aeolian transport system will nearly shut down once surface moisture greater than critical moisture threshold;(3)The correlation between aeolian mass flux and fetch length can be divided into three stages according to the equilibrium state of sediment transport:positive before equilibrium state,negative after equilibrium state and irrelevant during equilibrium state.Finally,some necessary future research directions in China are put forward,according to the present research situation of beach aeolian sediment transport influenced by tide.

36.Whole-cell bioreporters and risk assessment of environmental pollution: A proof-of-concept study using lead

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


Abstract:As the world burden of environmental contamination increases, it is of the utmost importance to develop streamlined approaches to environmental risk assessment in order to prioritize mitigation measures. Whole-cell biosensors or bioreporters and speciation modeling have both become of increasing interest to determine the bioavailability of pollutants, as bioavailability is increasingly in use as an indicator of risk. Herein, we examine whether bioreporter results are able to reflect expectations based on chemical reactivity and speciation modeling, with the hope to extend the research into a wider framework of risk assessment. We study a specific test case concerning the bioavailability of lead (Pb) in aqueous environments containing Pb-complexing ligands. Ligands studied include ethylene diamine tetra-acetic acid (EDTA), meso-2,3 dimercaptosuccinic acid (DMSA), leucine, methionine, cysteine, glutathione, and humic acid (HA), and we also performed experiments using natural water samples from Lake Tai (Taihu), the third largest lake in China. We find that EDTA, DMSA, cysteine, glutathione, and HA amendment significantly reduced Pb bioavailability with increasing ligand concentration according to a log-sigmoid trend. Increasing dissolved organic carbon in Taihu water also had the same effect, whereas leucine and methionine had no notable effect on bioavailability at the concentrations tested. We find that bioreporter results are in accord with the reduction of aqueous Pb2+ that we expect from the relative complexation affinities of the different ligands tested. For EDTA and HA, for which reasonably accurate ionization and complexation constants are known, speciation modeling is in agreement with bioreporter response to within the level of uncertainty recognised as reasonable by the United States Environmental Protection Agency for speciation-based risk assessment applications. These findings represent a first step toward using bioreporter technology to streamline the biological confirmation or validation of speciation modeling for use in environmental risk assessment. (C) 2017 Elsevier Ltd. All rights reserved,

37.Wild pollinators enhance oilseed rape yield in small-holder farming systems in China

Author:Zou, Y;Xiao, HJ;Bianchi, FJJA;Jauker, F;Luo, SD;van der Werf, W

Source:BMC ECOLOGY,2017,Vol.17

Abstract:Background: Insect pollinators play an important role in crop pollination, but the relative contribution of wild pollinators and honey bees to pollination is currently under debate. There is virtually no information available on the strength of pollination services and the identity of pollination service providers from Asian smallholder farming systems, where fields are small, and variation among fields is high. We established 18 winter oilseed rape (Brassica napus L.) fields along a large geographical gradient in Jiangxi province in China. In each field, oilseed rape plants were grown in closed cages that excluded pollinators and open cages that allowed pollinator access. The pollinator community was sampled by pan traps for the entire oilseed rape blooming period. Results: Oilseed rape plants from which insect pollinators were excluded had on average 38%% lower seed set, 17%% lower fruit set and 12%% lower yield per plant, but the seeds were 17%% heavier, and the caged plants had 28%% more flowers and 18%% higher aboveground vegetative biomass than plants with pollinator access. Oilseed rape plants thus compensate for pollination deficit by producing heavier seeds and more flowers. Regression analysis indicated that local abundance and diversity of wild pollinators were positively associated with seed set and yield/straw ratio, while honey bee abundance was not related to yield parameters. Conclusions: Wild pollinator abundance and diversity contribute to oilseed rape yield by enhancing plant resource allocation to seeds rather than to above-ground biomass. This study highlights the importance of the conservation of wild pollinators to support oilseed rape production in small-holder farming systems in China.

38.Enhancing Public Health Messaging: Discrete-Choice Experiment Evidence on the Design of HIV Testing Messages in China

Author:Durvasula, M;Pan, SW;Ong, JJ;Tang, WM;Cao, BL;Liu, CC;Terris-Prestholt, F;Tucker, JD


Abstract:Introduction. While a growing literature documents the effectiveness of public health messaging on social media, our understanding of the factors that encourage individuals to engage with and share messages is limited. In the context of human immunodeficiency virus (HIV) among men who have sex with men (MSM) in China, rising incidence and low testing rates despite decades of interventions suggest the need for effective, targeted messaging to reach underserved populations. Social media platforms and sex-seeking apps present a promising avenue, as web-based strategies can take advantage of existing trust within dense social networks. Methods. We conducted an online discrete-choice experiment in January 2017 with MSM from across China. Participants were presented with 6 choice tasks, each composed of 2 messages about HIV testing, and were asked in which scenario they were more likely to share the content. Participants were given information about the source of the HIV testing message, the social media sharing platform, and the recipients with whom they would share the message. They were given the option of sharing 1 message or neither. Multinomial and mixed logit models were used to model preferences within 4 subgroups. Results. In total, 885 MSM joined the survey, completing 4387 choice tasks. The most important attribute for 3 of the 4 subgroups was social media sharing platform. Men were more willing to share messages on sex-seeking mobile applications and less willing to share materials on generic (non-MSM) social media platforms. We found that men with more active online presences were less willing to share HIV testing messages on generic social media platforms. Conclusions. Our findings suggest that sex-seeking platforms represent a targeted, efficient method of actively engaging MSM in public health interventions.

39.Nutrient addition increases grassland sensitivity to droughts

Author:Bhaaath, S;Borer, ET;Biederman, LA;Blumenthal, DM;Fay, PA;Gherardi, LA;Knops, JMH;Leakey, ADB;Yahdjian, L;Seabloom, EW


Abstract:Grasslands worldwide are expected to experience an increase in extreme events such as drought, along with simultaneous increases in mineral nutrient inputs as a result of human industrial activities. These changes are likely to interact because elevated nutrient inputs may alter plant diversity and increase the sensitivity to droughts. Dividing a system's sensitivity to drought into resistance to change during the drought and rate of recovery after the drought generates insights into different dimensions of the system's resilience in the face of drought. Here, we examine the effects of experimental nutrient fertilization and the resulting diversity loss on the resistance to and recovery from severe regional droughts. We do this at 13 North American sites spanning gradients of aridity, five annual grasslands in California, and eight perennial grasslands in the Great Plains. We measured rate of resistance as the change in annual aboveground biomass (ANPP) per unit change in growing season precipitation as conditions declined from normal to drought. We measured recovery as the change in ANPP during the postdrought period and the return to normal precipitation. Resistance and recovery did not vary across the 400-mm range of mean growing season precipitation spanned by our sites in the Great Plains. However, chronic nutrient fertilization in the Great Plains reduced drought resistance and increased drought recovery. In the California annual grasslands, arid sites had a greater recovery postdrought than mesic sites, and nutrient addition had no consistent effects on resistance or recovery. Across all study sites, we found that predrought species richness in natural grasslands was not consistently associated with rates of resistance to or recovery from the drought, in contrast to earlier findings from experimentally assembled grassland communities. Taken together, these results suggest that human-induced eutrophication may destabilize grassland primary production, but the effects of this may vary across regions and flora, especially between perennial and annual-dominated grasslands.

40.Prevalence and Socio-economic Impacts of Malnutrition Among Children in Uganda

Author:Adebisi, YA;Ibrahim, K;Lucero-Prisno, DE;Ekpenyong, A;Micheal, AI;Chinemelum, IG;Sina-Odunsi, AB


Abstract:Malnutrition is one of the common problems that afflict the poor in low- and middle-income countries like Uganda. The rate of decline of malnutrition in the country has been very slow for the last 15 years. This problem is of utmost concern in this era of Sustainable Development Goals (SDGs) in which achieving the goals is imperative. The aim of our study was to review literature on the prevalence and socio-economic impacts of malnutrition among children under 5 in Uganda and provide recommendations to address identified gaps. This review assesses available evidences, including journal articles, country reports, the World Health Organization (WHO) reports, the United Nations International Children's Emergency Funds (UNICEF) reports, and other reports on issues pertaining to malnutrition among children in Uganda. Malnutrition, poverty, and chronic diseases are interconnected in such a way that each of the factors influences the presence and permanence of the other, resulting in a synergistic impact. The prevalence of acute and severe malnutrition among children under 5 is above the World Health Assembly target to reduce and maintain the prevalence under 5%% by 2025. There are also limited studies on etiology of anemia as regards its prevalence in Uganda. The study presents a better understanding of the social and economic impact of child malnutrition on the families and the country's development. The study also strongly suggests that, for Uganda to achieve sustainable development goal 2, financial investments by the government are necessary to address nutrition in the early stages of an individual's life.

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.
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