• Microbial oxidation of arsenite in a subarctic environment: diversity of arsenite oxidase genes and identification of a psychrotolerant arsenite oxidiser

      Osborne, Thomas H.; Jamieson, Heather E.; Hudson-Edwards, Karen A.; Nordstrom, D. Kirk; Walker, Stephen R.; Ward, Seamus A.; Santini, Joanne M. (Biomed Central, 2010-07-30)
      Arsenic is toxic to most living cells. The two soluble inorganic forms of arsenic are arsenite (+3) and arsenate (+5), with arsenite the more toxic. Prokaryotic metabolism of arsenic has been reported in both thermal and moderate environments and has been shown to be involved in the redox cycling of arsenic. No arsenic metabolism (either dissimilatory arsenate reduction or arsenite oxidation) has ever been reported in cold environments (i.e. < 10°C).
    • Models for oil refinery waste management using determined and fuzzy conditions

      Zhumadillayeva, Ainur; Orazbayеv, Batyr; Santeyeva, Saya; Dyussekeyev, Kanagat; Li, Rita Yi Man; Crabbe, M. James C.; Yue, Xiao-Guang; L.N.Gumilyov Eurasian National University, Kazakhstan; Hong Kong Shue Yan University; Rajamangala University of Technology Rattanakosin, Thailand; et al. (MDPI, 2020-06-03)
      This study developed models to solve problems of optimisation, production, and consumption in waste management based on methods of system analysis. Mathematical models of the problems of optimisation and sustainable waste management in deterministic conditions and in a fuzzy environment were formulated. The income from production was maximised considering environmental standards that apply to the field of macroeconomics and microeconomics. The proposed approach used MANAGER software to formalise and solve the problem of revenue optimisation with production waste management to optimise the production of oil products with waste management at a specific technological facility of the Atyrau oil refinery in Kazakhstan. Based on the combined application of the principles of maximin and Pareto optimality, a formulation of the problem of production optimisation with waste management was obtained and a heuristic algorithm for solving the formulated fuzzy optimisation problem with waste management was developed.
    • Resolving relationships in an exceedingly young Neotropical orchid lineage using Genotyping-by-sequencing data

      Pérez-Escobar, Oscar Alejandro; Bogarin, Diego; Schley, Rowan; Bateman, Richard M.; Gerlach, Günter; Harpke, Dörte; Brassac, Jonathan; Fernández-Mazuecos, Mario; Dodsworth, Steven; Hagsater, Eric; et al. (Elsevier, 2019-11-14)
      Poor morphological and molecular differentiation in recently diversified lineages is a widespread phenomenon in plants. Phylogenetic relationships within such species complexes are often difficult to resolve because of the low variability in traditional molecular loci. Furthermore, biological phenomena responsible for topological incongruence such as Incomplete Lineage Sorting (ILS) and hybridisation complicate the resolution of phylogenetic relationships among closely related taxa. In this study, we employ a Genotyping-by-sequencing (GBS) approach to disentangle evolutionary relationships within a species complex belonging to the Neotropical orchid genus Cycnoches. This complex includes seven taxa distributed through Central America and the Colombian Chocó, and is nested within a clade estimated to have first diversified in the early Quaternary. Previous phylogenies inferred from few loci failed to provide support for internal relationships within the complex. Our Neighbour-net and coalescent-based analyses inferred from ca. 13,000 GBS loci obtained from 31 individuals belonging to six of the seven traditionally accepted Cycnoches taxa provided a robust phylogeny for this group. The genus Cycnoches includes three main clades that are further supported by morphological traits and geographic distributions. Similarly, a topology reconstructed through maximum likelihood (ML) inference of concatenated GBS loci produced results that are comparable with those reconstructed through coalescence and network-based methods. Our comparative phylogenetic informativeness analyses suggest that the low support evident in the ML phylogeny might be attributed to the abundance of uninformative GBS loci, which can account for up to 50% of the total number of loci recovered. The phylogenomic framework provided here, as well as morphological evidence and geographical patterns, suggest that the six entities previously thought to be different species or subspecies might actually represent only three distinct segregates. We further discuss the limited phylogenetic informativeness found in our GBS approach and its utility to disentangle relationships within recent and rapidly evolving species complexes. Our study is the first to demonstrate the utility of GBS data to reconstruct relationships within young (~2 Ma) Neotropical plant clades, opening new avenues for studies of species complexes that populate the species-rich orchid family.
    • Salicylic acid collaborates with gene silencing to tomato defense against tomato yellow leaf curl virus (TYLCV)

      Li, Yunzhou; Muhammad, Tayab; Wang, Yong; Zhang, Dalong; Crabbe, M. James C.; Liang, Yan; Northwest A&F University; Guizhou University; Shangdong Agricultural University; University of Oxford; et al. (Pakistan Botanical Society, 2018-07-10)
      Antiviral research in plants has been focused on RNA silencing (i.e. RNA interference), and several studies suggest that salicylic acid (SA)-mediated resistance is a key part of plant antiviral defense. However, the antiviral defense mechanism of SA-mediation is still unclear, and several recent studies have suggested a connection between SA-mediated defense and RNA silencing, which needs further characterization in TYLCV infection. In this study, both SA-mediated defense and the RNA silencing mechanism were observed to play an important role in the antiviral response against TYLCV. First, we found that SA application enhanced the resistance to TYLCV in tomato plants. The expression of RNA-silencing-related genes, such as SlDCL1, SlDCL2, SlDCL4, SlRDR2, SlRDR3a, SlRDR6a, SlAGO1, and SlAGO4, were significantly triggered by exogenous SA application and inoculation with TYLCV, respectively. Furthermore, silencing of SlDCL2, SlDCL4 in tomato resulted in attenuated resistance to TYLCV, and reduced the expression of defense-related genes (SlPR1 and SlPR1b) in SA-mediated defense after infection with TYLCV, particularly in SlDCL2/SlDCL4-silenced plants. Taken together, we conclude that SA collaborates with gene silencing in tomato defense against TYLCV.
    • Scenarios for the development of smart grids in the UK: literature review

      Xenias, Demitrios; Axon, Colin; Balta-Ozkan, Nazmiye; Cipcigan, Liana; Connor, Peter; Davidson, Rosemary; Spence, Alexa; Taylor, Gary; Whitmarsh, Lorraine (UKERC, 2014-01-01)
      Smart grids are expected to play a central role in any transition to a low-carbon energy future, and much research is currently underway on practically every area of smart grids. However, it is evident that even basic aspects such as theoretical and operational definitions, are yet to be agreed upon and be clearly defined. Some aspects (efficient management of supply, including intermittent supply, two-way communication between the producer and user of electricity, use of IT technology to respond to and manage demand, and ensuring safe and secure electricity distribution) are more commonly accepted than others (such as smart meters) in defining what comprises a smart grid. It is clear that smart grid developments enjoy political and financial support both at UK and EU levels, and from the majority of related industries. The reasons for this vary and include the hope that smart grids will facilitate the achievement of carbon reduction targets, create new employment opportunities, and reduce costs relevant to energy generation (fewer power stations) and distribution (fewer losses and better stability). However, smart grid development depends on additional factors, beyond the energy industry. These relate to issues of public acceptability of relevant technologies and associated risks (e.g. data safety, privacy, cyber security), pricing, competition, and regulation; implying the involvement of a wide range of players such as the industry, regulators and consumers. The above constitute a complex set of variables and actors, and interactions between them. In order to best explore ways of possible deployment of smart grids, the use of scenarios is most adequate, as they can incorporate several parameters and variables into a coherent storyline. Scenarios have been previously used in the context of smart grids, but have traditionally focused on factors such as economic growth or policy evolution. Important additional socio-technical aspects of smart grids emerge from the literature review in this report and therefore need to be incorporated in our scenarios. These can be grouped into four (interlinked) main categories: supply side aspects, demand side aspects, policy and regulation, and technical aspects. 
    • Seasonal variations in carbon, nitrogen and phosphorus concentrations and C:N:P stoichiometry in different organs of a Larix principis-rupprechtii Mayr. plantation in the Qinling Mountains, China

      Li, Haliang; Crabbe, M. James C.; Xu, Fuli; Wang, Weiling; Ma, Lihua; Niu, Ruilong; Gao, Xing; Li, Xingxing; Zhang, Pei; Ma, Xin; et al. (Public library of science, 2017-09-22)
      Understanding how concentrations of elements and their stoichiometry change with plant growth and age is critical for predicting plant community responses to environmental change. Weusedlong-term field experiments to explore how the leaf, stem and root carbon (C), nitrogen (N) and phosphorous (P) concentrations and their stoichiometry changed with growth and stand age in a L.principis-rupprechtii Mayr. plantation from 2012–2015 in the Qinling Mountains, China. Our results showed that the C, N and P concentrations and stoichiometric ratios in different tissues of larch stands were affected by stand age, organ type andsampling month and displayed multiple correlations with increased stand age in different growing seasons. Generally, leaf C and N concentrations were greatest in the fast-growing season, but leaf P concentrations were greatest in the early growing season. However, no clear seasonal tendencies in the stem and root C, N and P concentrations were observed with growth. In contrast to N and P, few differences were found in organ-specific C concentrations. Leaf N:P was greatest in the fast-growing season, while C:N and C:P were greatest in the late-growing season. No clear variations were observed in stem and root C:N, C:P andN:Pthroughout the entire growing season, but leaf N:P was less than 14, suggesting that the growth of larch stands was limited by N in our study region. Compared to global plant element concentrations and stoichiometry, the leaves of larch stands had higher C, P, C:NandC:PbutlowerNandN:P,andtherootshadgreater PandC:NbutlowerN,C:Pand N:P. Our study provides baseline information for describing the changes in nutritional elements with plant growth, which will facilitates plantation forest management and restoration, and makes avaluable contribution to the global data pool on leaf nutrition and stoichiometry.
    • Seasonal variations in carbon, nitrogen and phosphorus concentrations and C:N:P stoichiometry in the leaves of differently aged Larix principis-rupprechtii Mayr. plantations

      Li, Hailiang; Crabbe, M. James C.; Xu, Fuli; Wang, Weiling; Niu, Ruilong; Gao, Xing; Zhang, Pei; Chen, Haikui; Northwest A & F University, Yangling; University of Oxford; et al. (MDPI, 2017-09-30)
      The concentrations and stoichiometry of certain elements (carbon, nitrogen and phosphorus) are critical to the maintenance of plant functional and environmental adaptation during plant growth. We explore how the concentrations of C, N and P and the ratios of C:N, C:P, and N:P in the leaves of differently aged Larix principis-rupprechtii Mayr. plantations changed with growing season and stand age from 2012 to 2015 in the Qinling Mountains, China. The results showed that the element concentration and stoichiometric ratios in leaves were significantly affected by sampling month, stand age and sampling year; and multiple correlations with stand age were observed in different growing seasons. Compared to global element concentrations and stoichiometry in plants, the leaves of larch stands in the study region had higher C and P concentrations and C:N and C:P ratios but lower N concentrations and N:P ratios than global levels. The leaf N:P ratios of all of the larch stands were generally less than 14, suggesting that the growth of larch stands was limited by N in the study region. Our study facilitates the management and restoration of forest plantation and provides a valuable contribution to the global pool of leaf nutrition and stoichiometry data.
    • Sustainability assessment of bioenergy from a global perspective: a review

      Wang, Jianliang; Yang, Yuru; Bentley, Yongmei; Geng, Xu; Liu, Xiaojie; China University of Petroleum; University of Bedfordshire; Chinese Academy of Sciences (MDPI, 2018-08-01)
      Bioenergy, as a renewable energy resource, is expected to see significant development in the future. However, a key issue that will affect this trend is sustainability of bioenergy. There have been many studies on this topic, but mainly focusing on only one- or two-dimensions of the issue, and also with much of the literature directed at studies of European regions. To help understand the wider scope of bioenergy sustainability, this paper reviews a broad range of current research on the topic, and places the literature into a multi-dimensional framework covering the economic, environmental and ecological, social, and land-related aspects of bioenergy sustainability, as well as a geographical analysis of the areas for which the studies have been carried out. The review indicates that it is hard to draw an overall conclusion on the sustainability of bioenergy because of limited studies or contradictory results in some aspects. In addition, this review shows that crop-based bioenergy and forest bioenergy are seen as the main sources of bioenergy, and that most studies discuss the final utilization of bioenergy as being for electricity generation. Finally, research directions for future study are suggested, based on the literature reviewed here.
    • Valuation impacts of environmental protection taxes and regulatory costs in heavy-polluting industries

      Tu, Wen-Jun; Yue, Xiao-Guang; Liu, Wei; Crabbe, M. James C.; Ningbo University; European University Cyprus; Porto Polytechnic; Qingdao University; Oxford University; University of Bedfordshire; et al. (MDPI, 2020-03-20)
      In 2016, the issue of the Environmental Protection Tax Law indicated the enhancement of environmental protection in China. This study examines the market reaction to firms in heavy-polluting industries, and the effects of external legal institutional quality and internal environmental disclosure on firm value around the passage of Environmental Protection Tax Law. Using an event study approach coupled with ordinary least square regressions, the researchers find a significantly negative market reaction to firms in heavy-polluting industries, but this negative reaction varies depending on the expected increase in future regulatory costs. Specifically, the above negative reaction is stronger when the firm reveals that itself or its subsidiary belongs to heavy-polluting industry, however it would be mitigated when a firm is in a region with better quality of legal institutions or discloses environmental improvement activities. Overall, the results are consistent with the market perceiving that the environmental protection tax law enacted would increase regulatory costs for firms in heavy-polluting industries, and also show the higher-quality regional legal institutions and more efforts on environmental protection could relieve the market’s pessimism caused by uncertainty.
    • Water use for shale gas extraction in the Sichuan Basin, China

      Wang, Jianliang; Liu, Mingming; Bentley, Yongmei; Feng, Lianyong; Zhang, Chunhua; China University of Petroleum; University of Bedfordshire; Economics & Technology Research Institute, Beijing (Elsevier, 2018-08-07)
      This study investigates the use of water for extracting shale gas in the Sichuan Basin of China. Both net water use and water intensity (i.e., water use per unit of gas produced) of shale wells are estimated by applying a process-based life cycle inventory (LCI) model. The results show that the net water use and water intensity are around 24500 m3/well and 1.9 m3 water/104m3 gas respectively, and that the fracturing and completion stage of shale gas extraction accounts for the largest share in net water use. A comparison shows that China's water use for shale gas extraction is generally higher than that of other countries. By considering the predicted annual drilling activities in the Sichuan Basin, we find that the annual water demand for shale gas development is likely to be negligible compared to total regional water supply. However, considering the water demand for shale gas extraction and the water demand from other sectors may make water availability a significant concern for China's shale gas development in the future.