Recent Submissions

  • A Case Study on the Microstructure of Fibrous Peat (West Lake, China)

    Wilkinson, Stephen; Zhao, Chaofa; Yang, Zhongxuam; Kun, Pan (Springer, 2018-09-21)
    The classification of peat soils generates a very large number of different types, from a descriptive perspective this is useful, however such a system generates too many options for engineering purposes. The behaviour of organic soils varies based on the quantity and type of organic material present within the soil. The effects of fibre content are particularly important. The West Lake in Hangzhou has been dredged many times during its history to allow it to maintain its beauty. During the most recent dredging the sludge from the lake was transported via a 4km pipeline and deposited inside the Jiangyangfan Reservoir. The organic soil situated in Jiangyangfan Ecopark is a particularly interesting peaty material. The organic sludge was mixed and homogenised during the transportation process, and then would have settled out within the reservoir. This resulted in a more than 20m thick peat layer deposited with an uneven surface. The Ecopark buildings were then constructed on top of this in 2008. A combined electron microscope and mechanical study of the microstructure and behaviour of the peat has been used to identify the engineering impact of the presence of relatively small numbers of fibres within the soil matrix. The fibres within the peat modify its behaviour such that it can no longer be understood within the typical critical state framework for soils. The peat starts to plastically deform from very small levels of applied stress, in addition it does not display a tension cut-off failure, and ultimately fails in shear.
  • Cost-effectiveness of using small vertebrates as indicators of disturbance.

    Peck, Mika Robert; Maddock, Simon T; Morales, Jorge Noe; Oñate, Hugolino; Mafla-Endara, Paola; Peñafiel, Vanessa Aguirre; Torres-Carvajal, Omar; Pozo-Rivera, Wilmer E; Cueva-Arroyo, Xavier A; Tolhurst, Bryony A (Wiley, 2014-10-01)
    In species-rich tropical forests, effective biodiversity management demands measures of progress, yet budgetary limitations typically constrain capacity of decision makers to assess response of biological communities to habitat change. One approach is to identify ecological-disturbance indicator species (EDIS) whose monitoring is also monetarily cost-effective. These species can be identified by determining individual species' responses to disturbance across a gradient; however, such responses may be confounded by factors other than disturbance. For example, in mountain environments the effects of anthropogenic habitat alteration are commonly confounded by elevation. EDIS have been identified with the indicator value (IndVal) metric, but there are weaknesses in the application of this approach in complex montane systems. We surveyed birds, small mammals, bats, and leaf-litter lizards in differentially disturbed cloud forest of the Ecuadorian Andes. We then incorporated elevation in generalized linear (mixed) models (GL(M)M) to screen for EDIS in the data set. Finally, we used rarefaction of species accumulation data to compare relative monetary costs of identifying and monitoring EDIS at equal sampling effort, based on species richness. Our GL(M)M generated greater numbers of EDIS but fewer characteristic species relative to IndVal. In absolute terms birds were the most cost-effective of the 4 taxa surveyed. We found one low-cost bird EDIS. In terms of the number of indicators generated as a proportion of species richness, EDIS of small mammals were the most cost-effective. Our approach has the potential to be a useful tool for facilitating more sustainable management of Andean forest systems.
  • Lizard diversity in response to human-induced disturbance in Andean Ecuador

    Tolhurst, Bryony; Peñafiel, Vanessa Aguirre; Mafla-Endara, Paola; Berg, Maureen J; Peck, Mika R; Maddock, Simon T (British Herpetological Society, 2016-01)
    The cloud-forests of the Western Ecuadorean Andes are highly diverse and under threat from anthropogenic habitat disturbance. Reptiles are sensitive to habitat change and are therefore useful indicators of ecosystem state. Overall diversity has been shown to be highest in old-growth (primary) forest, although older secondary forests can recover to near pre-disturbance levels. We systematically surveyed leaf-litter lizard diversity along a gradient of disturbance in a montane cloud-forest fragment whilst controlling for the potentially confounding effect of elevation. We deployed 21 pitfall trap-lines equally between primary forest, secondary forest of mid-age (18–30 years), and agroforestry, between three altitudinal bands for ten days each over a period of three years. We investigated diversity patterns using Chao 1 and 2 indices (estimated richness), effective species number (ESN), relative abundance of individual species, relative abundance of pooled species, and observed species richness. We also conducted an opportunistic inventory of reptile species. We recorded 7 species of leaf-litter lizards and 15 other species of squamate, the majority of which are rare, recently described and/or of restricted distribution. Elevation was strongly negatively correlated with diversity. Richness and most indices of diversity were higher in primary forest but abundance was similar in primary forest and agroforestry. ESN followed a negative linear response to disturbance but for all other measures agroforestry supported diversity that was either higher than or equal to secondary forest. We conclude that, particularly at high elevations, mid-aged secondary forest is depauperate of leaf-litter lizards but agroforestry potentially supports relatively large populations of generalist species.
  • A new species of death adder (Acanthophis: Serpentes: Elapidae) from north-western Australia

    Maddock, Simon T; Ellis, Ryan J; Doughty, Paul; Smith, Lawrence A; Wüster, Wolfgang (Magnolia Press, 2015-08-28)
    Australian death adders (genus Acanthophis) are highly venomous snakes with conservative morphology and sit-and-wait predatory habits, with only moderate taxonomic diversity that nevertheless remains incompletely understood. Analyses of mitochondrial and nuclear gene sequences and morphological characteristics of death adders in northern Australia reveal the existence of a new species from the Kimberley region of Western Australia and the Northern Territory, which we describe as Acanthophis cryptamydros sp. nov. Although populations from the Kimberley were previously considered conspecific with Northern Territory death adders of the A. rugosus complex, our mtDNA analysis indicates that its closest relatives are desert death adders, A. pyrrhus. We found that A. cryptamydros sp. nov. is distinct in both mtDNA and nDNA analysis, and possesses multiple morphological characteristics that allow it to be distinguished from all other Acanthophis species. This study further supports the Kimberley region as an area with high endemic biodiversity.
  • First record of Chrysopelea taprobanica Smith, 1943 (Squamata: Colubridae) from India

    Guptha, Bubesh; Prasad, Nimmakayla Venkata Sivaram; Maddock, Simon T; Deepak, V (Pensoft, 2015-01-01)
    Chrysopelea taprobanica Smith, 1943 was previously considered to be endemic to the dry and intermediate zones of Sri Lanka. However, an adult specimen of C. taprobanica was collected from Seshachalam Biosphere Reserve of Andhra Pradesh, India, being the first record of this snake species from India, significantly extending the known range of distribution of the species. The dry zones of peninsular India were connected with Sri Lanka as recently as ca. 17,000 years ago, which probably allowed movement of species between these two regions.
  • Technological and economic evaluation of conversion of potential flare gas to electricity in Nigeria

    Ojijiagwo, Emeka Nnanna; Oduoza, Chike F; Emekwuru, Nwabueze (Elsevier, 2018-06-11)
    Globally, over 100 billion cubic metres (BCM) of gas is flared annually and linked to an annual emission of 400 million tons of carbon dioxide. In Nigeria the annual gas production is valued at 33.21 BCM, out of which more than 50% of this volume is wasted through flaring, thereby emitting about 35 million tons of carbon dioxide. About 14.94 BCM of gas produced in Nigeria is used for a variety of activities including electricity generation. Despite this scenario, Nigeria is still unable to generate and distribute enough electricity for the citizenry. This paper therefore proposes the option to divert gas which is normally flared to generate electricity in Nigeria while minimising the associated environmental impacts. The research methodology was based on interviewing top level managers in an electricity generation company, and gas Production Company, as well as the researchers’ site observations within the two case companies. Results from this study showed that electricity generation could be improved from its current daily production rate of 4358 MW to about 12000 MW. This improvement comes from the use of 18.27 BCM of gas currently flared annually in Nigeria, which could potentially be diverted as fuel for 50 units of gas turbine with power output of 150 MW each, with an increase in daily electricity generation of 7500 MW. The study also incorporates an economic analysis for the option to generate electricity as aforementioned.
  • Guideline to Aid Project Managers in Conceptualizing and Implementing Risk Management in Building Projects

    Odimabo, Nengi; Oduoza, Chike F (Elsevier, 2018-06-11)
    Risk management has become a critical issue as a result of globalisation and the continued quest for greater returns. Construction organisations most especially in developing countries, approach risk management in building construction projects by using a set of practices that are normally insufficient, produce poor results often, and turn profitable building construction projects into loosing ventures. An integrated risk management approach allows construction organisations to consistently deliver superior performance while proactively managing risk. To address this gap, this paper offers a consolidated risk management system for building projects and provides project managers with guidelines for its proper implementation. In addition to helping project managers in improving risk management capability in building projects, the guideline profiled in this paper may also be of use to practitioners in other project risk management settings.
  • Influence of Lean Practice on Performance of Manufacturing SMEs in Kurdistan Region of Iraq (KRI)

    Mohammad, Ibrahim Salih; Oduoza, Chike F (Elsevier, 2018-06-11)
    Lean Manufacturing (LM) is a global initiative that can create continuous improvement in business performance by eliminating waste, reducing cycle time and promoting value-added activities. This study aims to examine empirically the influences of LM practices on the performance of SMEs. A comprehensive review of the LM literature was conducted, and seven variables were presented that dominate LM practices in Kurdistan Region of Iraq (KRI). Data was collected and analysed from 207 manufacturing SMEs showing that LM practices partially influence the business performance. The findings could be a good driver for introducing Lean techniques to the manufacturing SMEs within developing countries. It also provides valuable information for SMEs managers to improve the performance of their business in terms of increasing customer satisfaction, profitability, employee satisfaction, competitiveness and ergonomic design.
  • Chytrid Fungus (Batrachochytrium dendrobatidis) Undetected in the Two Orders of Seychelles Amphibians

    Labisko, Jim; Maddock, Simon T; Taylor, Michelle L; Chong-Seng, Lindsay; Gower, David J; Wynne, Felicity J; Wombwell, Emma; Morel, Charles; French, Georgia C A; Bunbury, Nancy; Bradfield, Kay S (Society For The Study Of Amphibians And Reptiles, 2015-03-16)
  • Downregulation of aquaporin 3 inhibits cellular proliferation, migration and invasion in the MDA‑MB‑231 breast cancer cell line

    Arif, Muhammad; Kitchen, Philip; Conner, Matthew; Hill, Eric; Nagel, David; Bill, Roslyn; Dunmore, Simon; Armesilla, Angel; Gross, Stephane; Carmichael, Amtul; Conner, Alex; Brown, James (Spandidos Publications, 2018-05-21)
    Aquaporins are membrane proteins that regulate cellular water flow. Recently, aquaporins have been proposed as mediators of cancer cell biology. A subset of aquaporins, referred to as aquaglyceroporins are known to facilitate the transport of glycerol. The present study describes the effect of gene knockdown of the aquaglyceroporin AQP3 on MDA‑MB‑231 breast cancer cell proliferation, migration, invasion, adherence and response to the chemotherapeutic agent 5‑fluorouracil. shRNA mediated AQP3 gene knockdown induced a 28% reduction in cellular proliferation (P<0.01), a 39% decrease in migration (P<0.0001), a 24% reduction in invasion (P<0.05) and a 25% increase in cell death at 100 µM 5‑FU (P<0.01). Analysis of cell permeability to water and glycerol revealed that MDA‑MB‑231 cells with knocked down AQP3 demonstrated a modest decrease in water permeability (17%; P<0.05) but a more marked decrease in glycerol permeability (77%; P<0.001). These results suggest that AQP3 has a role in multiple aspects of breast cancer cell pathophysiology and therefore represents a novel target for therapeutic intervention.
  • Integrated work-based placements – shifting the paradigm

    Smith, Sara (Emerald, 2018-05-14)
    Purpose The role of higher education institutions in enhancing capability development of the healthcare professionals workforce has resulted in work-based learning becoming an essential component of awards linked to professional registration. The purpose of this paper is to explore how key stakeholders (academics, workplace tutors and students) on a programme leading to registration as a Biomedical Scientist (BMS) position themselves in their role and the subsequent impact of this upon delivery of pre-registration training and the development of professional capability. Design/methodology/approach Constructivist grounded theory methodology and a mixed-methods approach were drawn upon for the study. Findings Findings expose the challenges of a positivist focus and assumptions around workplace learning and professional development presenting a barrier to developing professional capability. In addressing this barrier, two strategies of “doing the portfolio” and “gaining BMS currency” are adopted. The registration portfolio has become an objective reductionist measure of learning, reflecting the positivist typology of practice in this profession. Practical implications To ensure that students are supported to develop not only technical skills but also professional capability there is a need for a paradigm shift from a positivist episteme to one that embraces both the positivist and socio-cultural paradigms, viewing them as complimentary and parallel. Originality/value The study provides a novel insight into how stakeholders interact with the pressures of internal and external influences and the impact this has upon behaviours and strategies adopted. The theoretical understanding proposed has a range of implications for practice and for the development of practitioner capability through pre-registration training and beyond.
  • Cilia: Development and Disease

    Goggolidou, Paraskevi (CRC press, Taylor and Francis group, 2018-04)
    The scope of the book is to highlight the diverse roles of cilia in human development and disease. Almost all cell types form cilia and although they were first detected about 200 years ago, their significance was unclear. In the past ten years, it has become obvious that cilia have got sensory functions, as well as roles in motility and their mis-formation or the deregulation of the signaling pathways they control has been associated with defective development and human disease. Although research has concentrated on the role of the cilium in each organ, no effort has been made so far to bring all this information together and relate it to the various human diseases. This book aims to gather all the expertise that has been acquired on primary cilia and translate it into a medical and research context that will be of interest to postgraduate students, researchers, medics and scientists.
  • Creating Time and Responsive Dimensions in Science with Mobile Technology

    Khechara, Marin; Smith, S (Routledge, 2017-12-06)
    Mobile learning (mlearning) is now used extensively in higher education (HE) (El-Hussain & Cronje, 2010). The use of this technology, most commonly represented by smartphones (Ofcom, 2015), allows approaches such as the flipped classroom or ‘flipping’ to be facilitated (Bishop & Verleger, 2013). Content is recorded and made available online before class through a mobile device (Bergman & Sams, 2012), leaving face-to-face sessions free for other activities that support learning. The use of the flipped approach has been shown to have a range of positive impacts on students (Smith, Brown, Purnell & Martin, 2015; Witton, 2016).
  • Sleep patterns, daytime predation, and the evolution of diurnal sleep site selection in lorisiforms.

    Svensson, Magdalena S; Nekaris, K A I; Bearder, Simon K; Bettridge, Caroline M; Butynski, Thomas M; Cheyne, Susan M; Das, Nabajit; de Jong, Yvonne A; Luhrs, Averee M; Luncz, Lydia V; Maddock, Simon T; Perkin, Andrew; Pimley, Elizabeth; Poindexter, Stephanie A; Reinhardt, Kathleen D; Spaan, Denise; Stark, Danica J; Starr, Carly R; Nijman, Vincent (Wiley, 2018-07-01)
    Synthesize information on sleep patterns, sleep site use, and daytime predation at sleep sites in lorisiforms of Asia and Africa (10 genera, 36 species), and infer patterns of evolution of sleep site selection. We conducted fieldwork in 12 African and six Asian countries, collecting data on sleep sites, timing of sleep and predation during daytime. We obtained additional information from literature and through correspondence. Using a phylogenetic approach, we established ancestral states of sleep site selection in lorisiforms and traced their evolution. The ancestral lorisiform was a fur-clinger and used dense tangles and branches/forks as sleep sites. Use of tree holes and nests as sleep sites emerged ∼22 Mya (range 17-26 Mya) in Africa, and use of bamboo emerged ∼11 (7-14) Mya in Asia and later in Africa. Fur clinging and some sleep sites (e.g., tree holes, nests, but not bamboo or dense tangles) show strong phylogenetic signal. Nests are used by Galagoides, Paragalago, Galago and Otolemur; tree holes by Galago, Paragalago, Sciurocheirus and Perodicticus; tangles by Nycticebus, Loris, Galagoides, Galago, Euoticus, Otolemur, Perodicticus and Arctocebus; all but Sciurocheirus and Otolemur additionally sleep on branches/forks. Daytime predation may affect sleep site selection and sleep patterns in some species of Nycticebus, Galago, Galagoides, Otolemur and Perodicticus. Most lorisiforms enter their sleep sites around sunrise and leave around sunset; several are active during twilight or, briefly, during daytime. Variations in sleep behavior, sleep patterns and vulnerability to daytime predation provide a window into the variation that was present in sleep in early primates. Overall, lorisiforms use the daytime for sleeping and no species can be classified as cathemeral or polycyclic.
  • Next-Generation Mitogenomics: A Comparison of Approaches Applied to Caecilian Amphibian Phylogeny

    Maddock, Simon; Briscoe, Andrew; Wilkinson, Mark; Waeschenbach, Andrea; San Mauro, Diego; Day, Julia J; Littlewood, Tim J; Foster, Peter G; Nussbaum, Ronald A; Gower, David J (PLOS One, 2016-06-09)
  • Effect of zeolite types LTX and LTA on physicochemical parameters of drinking water sample in Ghana, assisted by light transmission experiment

    Sefa-Ntiri, B; Kwakye-Awuah, B; Williams, Craig (IJRET, 2014-03-01)
    In this study, the effect of zeolite types LTX and LTA, assisted by laser light transmission experiment on the physico-chemical parameters of drinking water samples have been investigated. Water samples were collected from rivers, streams, and wells from Central and Volta regions of Ghana, and zeolite masses of 0.2 and 0.5 g were added to 100 ml portions of the samples in turn. Laser light intensities transmitted through the samples before and after zeolite addition were measured and recorded. The results obtained showed raw water turbidity of 33.8 NTU and treated water turbidity of 3.0 NTU (WHO recommends the limit of 5 NTU for drinking water); transmitted light intensity for the raw and treated water samples of 0.3122 AU and 0.3345 AU, respectively. Our results also showed that water turbidity highly correlates the transmitted light intensity, and water conductivity depends on dissolved metal concentrations and temperature.
  • Fruit Fly Optimization Algorithm for Network-Aware Web Service Composition in the Cloud

    Shefu, Umar; Ali Safdar, Ghazanfar; Epiphaniou, Gregory (IJACSA, 2017-02-01)
    Service Oriented Computing (SOC) provides a framework for the realization of loosely coupled service oriented applications. Web services are central to the concept of SOC. Currently, research into how web services can be composed to yield QoS optimal composite service has gathered significant attention. However, the number and spread of web services across the cloud data centers has increased, thereby increasing the impact of the network on composite service performance experienced by the user. Recently, QoS-based web service composition techniques focus on optimizing web service QoS attributes such as cost, response time, execution time, etc. In doing so, existing approaches do not separate QoS of the network from web service QoS during service composition. In this paper, we propose a network-aware service composition approach which separates QoS of the network from QoS of web services in the Cloud. Consequently, our approach searches for composite services that are not only QoS-optimal but also have optimal QoS of the network. Our approach consists of a network model which estimates the QoS of the network in the form of network latency between services on the cloud. It also consists of a service composition technique based on fruit fly optimization algorithm which leverages the network model to search for low latency compositions without compromising service QoS levels. The approach is discussed and the results of evaluation are presented. The results indicate that the proposed approach is competitive in finding QoS optimal and low latency solutions when compared to recent techniques.
  • Quantisation feasibility and performance of RSS-based secret key extraction in VANETs

    Bottarelli, Mirko; Epiphaniou, Gregory; Kbaier Ben Ismail, Dhouha; Karadimas, Petros; Al-Khateeb, Haider (IEEE, 2018-06-12)
    Vehicular Ad Hoc Networks (VANETs) has emerged as a unique implementation of Mobile Ad Hoc Networks (MANETs). These networks promise to increase road safety and improve the driving experience by exploiting recent advances in wireless technologies for both intra-vehicle and inter-vehicle communications. Physical layer security is a promising alternative approach to secure communication in VANETs where physical and applications’ constraints encourage the use of lightweight and fast cryptographic algorithms. Our work focuses on the quantisation stage of the secret generation process, by reviewing existing schemes in the public domain and associated performance metrics. Evaluations are done through simulation with the aid of a wireless channel model which includes three-dimensional scattering and scatterers’ mobility. Preliminary findings show that RSS-based algorithms do not perform efficiently in the proposed vehicular stochastic wireless model. Hence they are not able to satisfy the typical low latency required in safetyrelated broadcasting messaging. We conclude that more research is desirable to design protocols capable of taking advantage from the nodes’ high-mobility and the consequent variability of both coherence intervals and level crossing rates, to further improve secret bit extraction throughput.
  • Testing for zero-modification relative to a negative-binomial distribution

    Wilson, Paul (International Statistical Modelling Society, 2018-07)

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