
Abertay University
UniversityDundee, United Kingdom
Research output, citation impact, and the most-cited recent papers from Abertay University (United Kingdom). Aggregated across the NobleBlocks index of 300M+ scholarly works.
Top-cited papers from Abertay University
Soil is the most complicated biomaterial on the planet. As with any material, the physical habitat is of prime importance in determining and regulating biological activity. However, until recently the opaque nature of soil has meant that any interrogation of its interior architecture has been relatively rudimentary, restricted to simple qualitative expressions of the physical heterogeneity that fail to relate to any specific function. However, new techniques and insights into the biophysical and biochemical processes of this inner space are leading to the developments of theoretical frameworks and experimental approaches that will allow us to sustainably manage Earth's most important resource. We introduce the concept that the soil-microbe system is self-organized and suggest new priorities for research based on an integrative approach that combines biochemistry and biophysics.
Recently, MOEA/D (multi-objective evolutionary algorithm based on decomposition) has achieved great success in the field of evolutionary multi-objective optimization and has attracted a lot of attention. It decomposes a multi-objective optimization problem (MOP) into a set of scalar subproblems using uniformly distributed aggregation weight vectors and provides an excellent general algorithmic framework of evolutionary multi-objective optimization. Generally, the uniformity of weight vectors in MOEA/D can ensure the diversity of the Pareto optimal solutions, however, it cannot work as well when the target MOP has a complex Pareto front (PF; i.e., discontinuous PF or PF with sharp peak or low tail). To remedy this, we propose an improved MOEA/D with adaptive weight vector adjustment (MOEA/D-AWA). According to the analysis of the geometric relationship between the weight vectors and the optimal solutions under the Chebyshev decomposition scheme, a new weight vector initialization method and an adaptive weight vector adjustment strategy are introduced in MOEA/D-AWA. The weights are adjusted periodically so that the weights of subproblems can be redistributed adaptively to obtain better uniformity of solutions. Meanwhile, computing efforts devoted to subproblems with duplicate optimal solution can be saved. Moreover, an external elite population is introduced to help adding new subproblems into real sparse regions rather than pseudo sparse regions of the complex PF, that is, discontinuous regions of the PF. MOEA/D-AWA has been compared with four state of the art MOEAs, namely the original MOEA/D, Adaptive-MOEA/D, [Formula: see text]-MOEA/D, and NSGA-II on 10 widely used test problems, two newly constructed complex problems, and two many-objective problems. Experimental results indicate that MOEA/D-AWA outperforms the benchmark algorithms in terms of the IGD metric, particularly when the PF of the MOP is complex.
Alcoholic beverages are produced following the fermentation of sugars by yeasts, mainly (but not exclusively) strains of the species, Saccharomyces cerevisiae. The sugary starting materials may emanate from cereal starches (which require enzymatic pre-hydrolysis) in the case of beers and whiskies, sucrose-rich plants (molasses or sugar juice from sugarcane) in the case of rums, or from fruits (which do not require pre-hydrolysis) in the case of wines and brandies. In the presence of sugars, together with other essential nutrients such as amino acids, minerals and vitamins, S. cerevisiae will conduct fermentative metabolism to ethanol and carbon dioxide (as the primary fermentation metabolites) as the cells strive to make energy and regenerate the coenzyme NAD+ under anaerobic conditions. Yeasts will also produce numerous secondary metabolites which act as important beverage flavour congeners, including higher alcohols, esters, carbonyls and sulphur compounds. These are very important in dictating the final flavour and aroma characteristics of beverages such as beer and wine, but also in distilled beverages such as whisky, rum and brandy. Therefore, yeasts are of vital importance in providing the alcohol content and the sensory profiles of such beverages. This Introductory Chapter reviews, in general, the growth, physiology and metabolism of S. cerevisiae in alcoholic beverage fermentations.
Abstract Background Pseudomonas fluorescens are common soil bacteria that can improve plant health through nutrient cycling, pathogen antagonism and induction of plant defenses. The genome sequences of strains SBW25 and Pf0-1 were determined and compared to each other and with P. fluorescens Pf-5. A functional genomic in vivo expression technology (IVET) screen provided insight into genes used by P. fluorescens in its natural environment and an improved understanding of the ecological significance of diversity within this species. Results Comparisons of three P. fluorescens genomes (SBW25, Pf0-1, Pf-5) revealed considerable divergence: 61% of genes are shared, the majority located near the replication origin. Phylogenetic and average amino acid identity analyses showed a low overall relationship. A functional screen of SBW25 defined 125 plant-induced genes including a range of functions specific to the plant environment. Orthologues of 83 of these exist in Pf0-1 and Pf-5, with 73 shared by both strains. The P. fluorescens genomes carry numerous complex repetitive DNA sequences, some resembling Miniature Inverted-repeat Transposable Elements (MITEs). In SBW25, repeat density and distribution revealed 'repeat deserts' lacking repeats, covering approximately 40% of the genome. Conclusions P. fluorescens genomes are highly diverse. Strain-specific regions around the replication terminus suggest genome compartmentalization. The genomic heterogeneity among the three strains is reminiscent of a species complex rather than a single species. That 42% of plant-inducible genes were not shared by all strains reinforces this conclusion and shows that ecological success requires specialized and core functions. The diversity also indicates the significant size of genetic information within the Pseudomonas pan genome.
Consensual qualitative research: A practical resource for investigating social science phenomena. Edited by Clara E. Hill (2012). Washington DC: American Psychological Association. 329 pages, $59.9...
Concerns have been growing about the veracity of psychological research. Many findings in psychological science are based on studies with insufficient statistical power and nonrepresentative samples, or may otherwise be limited to specific, ungeneralizable settings or populations. Crowdsourced research, a type of large-scale collaboration in which one or more research projects are conducted across multiple lab sites, offers a pragmatic solution to these and other current methodological challenges. The Psychological Science Accelerator (PSA) is a distributed network of laboratories designed to enable and support crowdsourced research projects. These projects can focus on novel research questions, or attempt to replicate prior research, in large, diverse samples. The PSA's mission is to accelerate the accumulation of reliable and generalizable evidence in psychological science. Here, we describe the background, structure, principles, procedures, benefits, and challenges of the PSA. In contrast to other crowdsourced research networks, the PSA is ongoing (as opposed to time-limited), efficient (in terms of re-using structures and principles for different projects), decentralized, diverse (in terms of participants and researchers), and inclusive (of proposals, contributions, and other relevant input from anyone inside or outside of the network). The PSA and other approaches to crowdsourced psychological science will advance our understanding of mental processes and behaviors by enabling rigorous research and systematically examining its generalizability.
Biological soil thin-sections and a combination of image analysis and geostatistical tools were used to conduct a detailed investigation into the distribution of bacteria in soil and their relationship with pores. The presence of spatial patterns in the distribution of bacteria was demonstrated at the microscale, with ranges of spatial autocorrelation of 1 mm and below. Bacterial density gradients were found within bacterial patches in topsoil samples and also in one subsoil sample. Bacterial density patches displayed a mosaic of high and low values in the remaining subsoil samples. Anisotropy was detected in the spatial structure of pores, but was not detected in relation to the distribution of bacteria. No marked trend as a function of distance to the nearest pore was observed in bacterial density values in the topsoil, but in the subsoil bacterial density was greatest close to pores and decreased thereafter. Bacterial aggregation was greatest in the cropped topsoil, though no consistent trends were found in the degree of bacterial aggregation as a function of distance to the nearest pore. The implications of the results presented for modelling and predicting bacterial activity in soil are discussed.
Asymptotics and Mellin-Barnes Integrals, first published in 2001, provides an account of the use and properties of a type of complex integral representation that arises frequently in the study of special functions typically of interest in classical analysis and mathematical physics. After developing the properties of these integrals, their use in determining the asymptotic behaviour of special functions is detailed. Although such integrals have a long history, the book's account includes recent research results in analytic number theory and hyperasymptotics. The book also fills a gap in the literature on asymptotic analysis and special functions by providing a thorough account of the use of Mellin-Barnes integrals that is otherwise not available in other standard references on asymptotics.
Purpose This paper seeks to present findings from an SME case study situated in the computer games industry, the youngest and fastest growing of the new digital industries. The study aims to examine changing people management practices as the case company undergoes industry‐typical strategic change to embark on explorative innovation and it seeks to argue that maintaining an organisational context conducive to innovation over time risks turning into a contest between management and employees, as both parties interpret organisational pressures from their different perspectives. Design/methodology/approach A single case study design is used as the appropriate methodology to generate in‐depth qualitative data from multiple organisational member perspectives. Findings Findings indicate that management and worker perspectives on innovation as strategic change and the central people management practices required to support this differ significantly, resulting in tensions and organisational strain. As the company moves to the production of IP work, the need for more effective duality management arises. Research limitations/implications The single case study has limitations in terms of generalisability. Multiple data collection and triangulation were used to mitigate the limitations. Practical implications The economic contribution of small businesses in the new creative industries is widely acknowledged. While the sector shows high business birth rates, the business failure rate is equally high. This remains of concern for policy makers. This study aims to contribute to understanding why businesses in the sector either fail to grow or decline. Social implications The economic contribution of small businesses in the new creative industries is widely acknowledged. While the sector shows high business birth rates, the business failure rate is equally high. This remains of concern for policy makers. This study aims to contribute to understanding why businesses in the sector either fail to grow or decline. Originality/value Few qualitative studies have examined people management practices in the industry in the context of organisational/strategic change, and few have adopted a process perspective.
The survival of all microbes depends upon their ability to respond to environmental challenges. To establish infection, pathogens such as Candida albicans must mount effective stress responses to counter host defences while adapting to dynamic changes in nutrient status within host niches. Studies of C. albicans stress adaptation have generally been performed on glucose-grown cells, leaving the effects of alternative carbon sources upon stress resistance largely unexplored. We have shown that growth on alternative carbon sources, such as lactate, strongly influence the resistance of C. albicans to antifungal drugs, osmotic and cell wall stresses. Similar trends were observed in clinical isolates and other pathogenic Candida species. The increased stress resistance of C. albicans was not dependent on key stress (Hog1) and cell integrity (Mkc1) signalling pathways. Instead, increased stress resistance was promoted by major changes in the architecture and biophysical properties of the cell wall. Glucose- and lactate-grown cells displayed significant differences in cell wall mass, ultrastructure, elasticity and adhesion. Changes in carbon source also altered the virulence of C. albicans in models of systemic candidiasis and vaginitis, confirming the importance of alternative carbon sources within host niches during C. albicans infections.
• Plant root mucilages contain powerful surfactants that will alter the interaction of soil solids with water and ions, and the rates of microbial processes. • The lipid composition of maize, lupin and wheat root mucilages was analysed by thin layer chromatography and gas chromatography-mass spectrometry. A commercially available phosphatidylcholine (lecithin), chemically similar to the phospholipid surfactants identified in the mucilages, was then used to evaluate its effects on selected soil properties. • The lipids found in the mucilages were principally phosphatidylcholines, composed mainly of saturated fatty acids, in contrast to the lipids extracted from root tissues. In soil at low tension, lecithin reduced the water content at any particular tension by as much as 10 and 50% in soil and acid-washed sand, respectively. Lecithin decreased the amount of phosphate adsorption in soil and increased the phosphate concentration in solution by 10%. The surfactant also reduced net rates of ammonium consumption and nitrate production in soil. • These experiments provide the first evidence we are aware of that plant-released surfactants will significantly modify the biophysical environment of the rhizosphere.
Fully articulated hand tracking promises to enable fundamentally new interactions with virtual and augmented worlds, but the limited accuracy and efficiency of current systems has prevented widespread adoption. Today's dominant paradigm uses machine learning for initialization and recovery followed by iterative model-fitting optimization to achieve a detailed pose fit. We follow this paradigm, but make several changes to the model-fitting, namely using: (1) a more discriminative objective function; (2) a smooth-surface model that provides gradients for non-linear optimization; and (3) joint optimization over both the model pose and the correspondences between observed data points and the model surface. While each of these changes may actually increase the cost per fitting iteration, we find a compensating decrease in the number of iterations. Further, the wide basin of convergence means that fewer starting points are needed for successful model fitting. Our system runs in real-time on CPU only, which frees up the commonly over-burdened GPU for experience designers. The hand tracker is efficient enough to run on low-power devices such as tablets. We can track up to several meters from the camera to provide a large working volume for interaction, even using the noisy data from current-generation depth cameras. Quantitative assessments on standard datasets show that the new approach exceeds the state of the art in accuracy. Qualitative results take the form of live recordings of a range of interactive experiences enabled by this new approach.
This study examines the value of voluntary and mandatory disclosure in a market that applies International Accounting Standards (IAS) with limited penalties for non compliance. The lack of enforcement creates an element of choice in the level of mandatory disclosure by companies. Using panel-data analysis, our empirical results show that, after controlling for factors such as asset size and profitability, mandatory disclosure has a highly significant but negative relationship with firm value. This result, although puzzling from a traditional perspective, is consistent with the predictions of analytical accounting models, which emphasize the complex interplay of factors determining disclosure effects. Our results also show that voluntary disclosure has a positive but insignificant association with firm value. This lack of statistical significance supports the view that there is a complex interplay of different factors determining the relationship between disclosure and firm value.
Plasmids drive genomic diversity in bacteria via horizontal gene transfer [1Thomas C.M. Nielsen K.M. Mechanisms of, and barriers to, horizontal gene transfer between bacteria.Nat. Rev. Microbiol. 2005; 3: 711-721Crossref PubMed Scopus (1283) Google Scholar, 2Jain R. Rivera M.C. Moore J.E. Lake J.A. Horizontal gene transfer accelerates genome innovation and evolution.Mol. Biol. Evol. 2003; 20: 1598-1602Crossref PubMed Scopus (242) Google Scholar]; nevertheless, explaining their survival in bacterial populations is challenging [3Harrison E. Brockhurst M.A. Plasmid-mediated horizontal gene transfer is a coevolutionary process.Trends Microbiol. 2012; 20: 262-267Abstract Full Text Full Text PDF PubMed Scopus (194) Google Scholar]. Theory predicts that irrespective of their net fitness effects, plasmids should be lost: when parasitic (costs outweigh benefits), plasmids should decline due to purifying selection [4Bergstrom C.T. Lipsitch M. Levin B.R. 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Commun. 2015; 6: 6845Crossref PubMed Scopus (102) Google Scholar], the propensity for this to occur across the parasitism-mutualism continuum is unknown. We experimentally evolved Pseudomonas fluorescens and its mercury resistance mega-plasmid, pQBR103 [16Tett A. Spiers A.J. Crossman L.C. Ager D. Ciric L. Dow J.M. Fry J.C. Harris D. Lilley A. Oliver A. et al.Sequence-based analysis of pQBR103; a representative of a unique, transfer-proficient mega plasmid resident in the microbial community of sugar beet.ISME J. 2007; 1: 331-340PubMed Google Scholar], across an environment-mediated parasitism-mutualism continuum. Compensatory evolution stabilized plasmids by rapidly ameliorating the cost of plasmid carriage in all environments. Genomic analysis revealed that, in both parasitic and mutualistic treatments, evolution repeatedly targeted the gacA/gacS bacterial two-component global regulatory system while leaving the plasmid sequence intact. Deletion of either gacA or gacS was sufficient to completely ameliorate the cost of plasmid carriage. Mutation of gacA/gacS downregulated the expression of ∼17% of chromosomal and plasmid genes and appears to have relieved the translational demand imposed by the plasmid. Chromosomal capture of mercury resistance accompanied by plasmid loss occurred throughout the experiment but very rarely invaded to high frequency, suggesting that rapid compensatory evolution can limit this process. Compensatory evolution can explain the widespread occurrence of plasmids and allows bacteria to retain horizontally acquired plasmids even in environments where their accessory genes are not immediately useful.
The concept of transformation in relation to climate and other global change is increasingly receiving attention. The concept provides important opportunities to help examine how rapid and fundamental change to address contemporary global challenges can be facilitated. This paper contributes to discussions about transformation by providing a social science, arts and humanities perspective to open up discussion and set out a research agenda about what it means to transform and the dimensions, limitations and possibilities for transformation. Key focal areas include: (1) change theories; (2) knowing whether transformation has occurred or is occurring; (3) knowledge production and use; (4) governance; (5) how dimensions of social justice inform transformation; (6) the limits of human nature; (7) the role of the utopian impulse; (8) working with the present to create new futures; and (9) human consciousness. In addition to presenting a set of research questions around these themes the paper highlights that much deeper engagement with complex social processes is required; that there are vast opportunities for social science, humanities and the arts to engage more directly with the climate challenge; that there is a need for a massive upscaling of efforts to understand and shape desired forms of change; and that, in addition to helping answer important questions about how to facilitate change, a key role of the social sciences, humanities and the arts in addressing climate change is to critique current societal patterns and to open up new thinking. Through such critique and by being more explicit about what is meant by transformation, greater opportunities will be provided for opening up a dialogue about change, possible futures and about what it means to re-shape the way in which people live.
Effective coaching is a mixture of pedagogy and principles of sciences, e.g., motor skill acquisition, sociology, and physiology, often referred to as the science of coaching. Instinctive or intuitive coaching has often been incorrectly viewed as the art of coaching. More important should be how coaches develop knowledge, how they access that knowledge at the appropriate times and how this affects their decision-making process. The study of expert coaches should allow inferences to be drawn from their development and applied to coach education. This article intends to clarify coaching expertise and examine the role of tacit knowledge within coaching. The lack of a clear development pathway for aspiring expert coaches is a clear indicator that the current coach education system needs review. Any effective education system should be based on knowledge and understanding rather than mimicry and the implications for the future of coach education are considered.
Reicher has recently developed the social identity model of crowd behaviour based on self-categorization theory (SCT). This model begins to tackle the thorny theoretical problems posed by the dynamic nature of crowd action (Reicher, 1996b). The present paper describes an ethnographic study of a crowd event in which there were changes in the inter-group relationships over time. It is suggested that the laboratory evidence in support of SCT is complemented by ethnographic research of this type. By exploring situations in which definitions of context and/or categories are not purposefully manipulated, we can demonstrate the explanatory power of a dynamic and interactive approach to social categorization.
Purpose Prior studies have suggested that organizational and environmental antecedents are influential to the development of a balance dimension of innovation ambidexterity, which are proposed to be central to superior firm performance. However, little is known about how such antecedents affect the shaping of innovation ambidexterity in small to medium‐sized enterprises (SMEs) and how these innovations go on to shape firm performance. This paper aims to examine internal and external antecedents of SMEs' innovation ambidexterity outcomes. Design/methodology/approach The research used a survey method to investigate the 1,000 small‐and medium sized enterprises in Scotland. Firms were randomly selected from the FAME database. Of this sample, 265 firms (26.5 percent) responded to the survey. Findings The data analysis reveals that internal organizational structures in a highly dynamic environment stimulate the appearance of innovation ambidexterity. Moreover, it is found that the relationship between organizational and environmental forces and firm performance is partially mediated by a balance dimension of innovation ambidexterity. Practical implications The results show how dangerous the lack of adequate research of these issues at the SME level is. By contrast to larger firms, the results show how internal organizational structures and external environmental conditions affect SMEs to pursue a balance dimension of innovation ambidexterity. Originality/value Prior studies have paid little attention to the effects of internal organizational structures and external environmental conditions on the appearance of a balance dimension of innovation ambidexterity within SMEs. This paper fills some of the gaps.
Traditional crowd theory decontextualizes crowd incidents and explains behaviour entirely in terms of processes internal to the crowd itself. This ignores the fact that such incidents are characteristically intergroup encounters and draws attention away from the role of groups such as the police in the development of events. This paper begins to rectify this omission through an analysis of interviews with 26 Public Order trained police concerning crowds in general and the Poll Tax ‘riot’ of 31 March 1990 in particular. The analysis shows that, despite a perception of crowd composition as heterogeneous, officers perceive crowd dynamics as involving an anti-social minority seeking to exploit the mindlessness of ordinary people in the mass. Consequently, all crowds are seen as potentially dangerous and, in situations of actual conflict, all crowd members are seen as equally dangerous. In addition, police tactics for dealing with disorder make it very difficult to distinguish between individuals or subgroups in the crowd. This convergence of ideological and practical factors leads to the police treating crowds in disorder as an homogeneous whole. It is argued that such action can often play an important role in escalating (if not initiating) collective conflict and is also a key component of social change in crowd contexts. © 1998 John Wiley & Sons, Ltd.
Cryopreservation techniques exist for some 100-plant species. Cryopreservation for the long-term conservation of in vitro germplasm results in the exposure of tissues to physical, chemical and physiological stresses causing cryoinjury. Although, the effects of cryoinjury upon the genome are often unknown, any accumulative DNA polymorphisms may not be induced by cryopreservation per se but are the result of the whole culture-cryoprotection-regeneration process. It is desirable to assess the genetic integrity of plants surviving cryogenic storage to determine if they are true to type after cryopreservation. This can be done at the phenotypic, histological, cytological, biochemical and molecular levels. The relevance of these approaches to stability investigations is discussed with their limitations. This review provides a definition for Cryobionomics - a novel term describing the re-modelled concept of genetic stability and the re-introduction of cryopreserved plants into the environment.