Showing papers by "Royal Holloway, University of London published in 2010"

Review of Particle Physics

Abstract: This biennial Review summarizes much of particle physics. Using data from previous editions, plus 2158 new measurements from 551 papers, we list, evaluate, and average measured properties of gauge bosons, leptons, quarks, mesons, and baryons. We also summarize searches for hypothetical particles such as Higgs bosons, heavy neutrinos, and supersymmetric particles. All the particle properties and search limits are listed in Summary Tables. We also give numerous tables, figures, formulae, and reviews of topics such as the Standard Model, particle detectors, probability, and statistics. Among the 108 reviews are many that are new or heavily revised including those on neutrino mass, mixing, and oscillations, QCD, top quark, CKM quark-mixing matrix, V-ud & V-us, V-cb & V-ub, fragmentation functions, particle detectors for accelerator and non-accelerator physics, magnetic monopoles, cosmological parameters, and big bang cosmology.

Towards a Politics of Mobility

Abstract: This paper proposes an approach to mobility that takes both historical mobilities and forms of immobility seriously. It is argued that is important for the development of a politics of mobility. To...

Genome Sequence of the Pea Aphid Acyrthosiphon pisum

Abstract: Aphids are important agricultural pests and also biological models for studies of insect-plant interactions, symbiosis, virus vectoring, and the developmental causes of extreme phenotypic plasticity. Here we present the 464 Mb draft genome assembly of the pea aphid Acyrthosiphon pisum. This first published whole genome sequence of a basal hemimetabolous insect provides an outgroup to the multiple published genomes of holometabolous insects. Pea aphids are host-plant specialists, they can reproduce both sexually and asexually, and they have coevolved with an obligate bacterial symbiont. Here we highlight findings from whole genome analysis that may be related to these unusual biological features. These findings include discovery of extensive gene duplication in more than 2000 gene families as well as loss of evolutionarily conserved genes. Gene family expansions relative to other published genomes include genes involved in chromatin modification, miRNA synthesis, and sugar transport. Gene losses include genes central to the IMD immune pathway, selenoprotein utilization, purine salvage, and the entire urea cycle. The pea aphid genome reveals that only a limited number of genes have been acquired from bacteria; thus the reduced gene count of Buchnera does not reflect gene transfer to the host genome. The inventory of metabolic genes in the pea aphid genome suggests that there is extensive metabolite exchange between the aphid and Buchnera, including sharing of amino acid biosynthesis between the aphid and Buchnera. The pea aphid genome provides a foundation for post-genomic studies of fundamental biological questions and applied agricultural problems.

Modelling the influence of human behaviour on the spread of infectious diseases: a review

Abstract: Human behaviour plays an important role in the spread of infectious diseases, and understanding the influence of behaviour on the spread of diseases can be key to improving control efforts. While behavioural responses to the spread of a disease have often been reported anecdotally, there has been relatively little systematic investigation into how behavioural changes can affect disease dynamics. Mathematical models for the spread of infectious diseases are an important tool for investigating and quantifying such effects, not least because the spread of a disease among humans is not amenable to direct experimental study. Here, we review recent efforts to incorporate human behaviour into disease models, and propose that such models can be broadly classified according to the type and source of information which individuals are assumed to base their behaviour on, and according to the assumed effects of such behaviour. We highlight recent advances as well as gaps in our understanding of the interplay between infectious disease dynamics and human behaviour, and suggest what kind of data taking efforts would be helpful in filling these gaps.

Refugia revisited: individualistic responses of species in space and time

Abstract: Climate change in the past has led to significant changes in species' distributions. However, how individual species respond to climate change depends largely on their adaptations and environmental tolerances. In the Quaternary, temperate-adapted taxa are in general confined to refugia during glacials while cold-adapted taxa are in refugia during interglacials. In the Northern Hemisphere, evidence appears to be mounting that in addition to traditional southern refugia for temperate species, cryptic refugia existed in the North during glacials. Equivalent cryptic southern refugia, to the south of the more conventional high-latitude polar refugia, exist in montane areas during periods of warm climate, such as the current interglacial. There is also a continental/oceanic longitudinal gradient, which should be included in a more complete consideration of the interaction between species ranges and climates. Overall, it seems clear that there is large variation in both the size of refugia and the duration during which species are confined to them. This has implications for the role of refugia in the evolution of species and their genetic diversity.

Functional and evolutionary insights from the genomes of three parasitoid Nasonia species.

Abstract: We report here genome sequences and comparative analyses of three closely related parasitoid wasps: Nasonia vitripennis, N. giraulti, and N. longicornis. Parasitoids are important regulators of arthropod populations, including major agricultural pests and disease vectors, and Nasonia is an emerging genetic model, particularly for evolutionary and developmental genetics. Key findings include the identification of a functional DNA methylation tool kit; hymenopteran-specific genes including diverse venoms; lateral gene transfers among Pox viruses, Wolbachia, and Nasonia; and the rapid evolution of genes involved in nuclear-mitochondrial interactions that are implicated in speciation. Newly developed genome resources advance Nasonia for genetic research, accelerate mapping and cloning of quantitative trait loci, and will ultimately provide tools and knowledge for further increasing the utility of parasitoids as pest insect-control agents.

Trophic level asynchrony in rates of phenological change for marine, freshwater and terrestrial environments

Abstract: Recent changes in the seasonal timing (phenology) of familiar biological events have been one of the most conspicuous signs of climate change. However, the lack of a standardized approach to analysing change has hampered assessment of consistency in such changes among different taxa and trophic levels and across freshwater, terrestrial and marine environments. We present a standardized assessment of 25 532 rates of phenological change for 726 UK terrestrial, freshwater and marine taxa. The majority of spring and summer events have advanced, and more rapidly than previously documented. Such consistency is indicative of shared large scale drivers. Furthermore, average rates of change have accelerated in a way that is consistent with observed warming trends. Less coherent patterns in some groups of organisms point to the agency of more local scale processes and multiple drivers. For the first time we show a broad scale signal of differential phenological change among trophic levels; across environments advances in timing were slowest for secondary consumers, thus heightening the potential risk of temporal mismatch in key trophic interactions. If current patterns and rates of phenological change are indicative of future trends, future climate warming may exacerbate trophic mismatching, further disrupting the functioning, persistence and resilience of many ecosystems and having a major impact on ecosystem services.

Distinct and Overlapping Functional Zones in the Cerebellum Defined by Resting State Functional Connectivity

Abstract: The cerebellum processes information from functionally diverse regions of the cerebral cortex. Cerebellar input and output nuclei have connections with prefrontal, parietal, and sensory cortex as well as motor and premotor cortex. However, the topography of the connections between the cerebellar and cerebral cortices remains largely unmapped, as it is relatively unamenable to anatomical methods. We used resting-state functional magnetic resonance imaging to define subregions within the cerebellar cortex based on their functional connectivity with the cerebral cortex. We mapped resting-state functional connectivity voxel-wise across the cerebellar cortex, for cerebral-cortical masks covering prefrontal, motor, somatosensory, posterior parietal, visual, and auditory cortices. We found that the cerebellum can be divided into at least 2 zones: 1) a primary sensorimotor zone (Lobules V, VI, and VIII), which contains overlapping functional connectivity maps for domain-specific motor, somatosensory, visual, and auditory cortices; and 2) a supramodal zone (Lobules VIIa, Crus I, and II), which contains overlapping functional connectivity maps for prefrontal and posterior-parietal cortex. The cortical connectivity of the supramodal zone was driven by regions of frontal and parietal cortex which are not directly involved in sensory or motor processing, including dorsolateral prefrontal cortex and the frontal pole, and the inferior parietal lobule.

Observation of a centrality-dependent dijet asymmetry in lead-lead collisions at √sNN=2.76 Tev with the ATLAS detector at the LHC

Abstract: By using the ATLAS detector, observations have been made of a centrality-dependent dijet asymmetry in the collisions of lead ions at the Large Hadron Collider. In a sample of lead-lead events with a per-nucleon center of mass energy of 2.76 TeV, selected with a minimum bias trigger, jets are reconstructed in fine-grained, longitudinally segmented electromagnetic and hadronic calorimeters. The transverse energies of dijets in opposite hemispheres are observed to become systematically more unbalanced with increasing event centrality leading to a large number of events which contain highly asymmetric dijets. This is the first observation of an enhancement of events with such large dijet asymmetries, not observed in proton-proton collisions, which may point to an interpretation in terms of strong jet energy loss in a hot, dense medium.

Trade-offs in corporate sustainability: you can't have your cake and eat it

Abstract: The mainstream of the literature on corporate sustainability follows the win-win paradigm, according to which economic, environmental and social sustainability aspects can be achieved simultaneously; indeed, corporate sustainability has often been defined by the intersection of these three areas. However, given the multi-faceted and complex nature of sustainable development, we argue that trade-offs and conflicts in corporate sustainability are the rule rather than the exception. Turning a blind eye to trade-offs thus results in a limited perspective on corporate contributions to sustainable development. In order to overcome this situation, we propose an initial framework for the analysis of trade-offs in corporate sustainability. By doing so, we pursue two aims. First, the framework serves as a starting point for a more systematic analysis of trade-offs in corporate sustainability, as it identifies different levels and dimensions to characterize such trade-offs. Second, it serves to contextualize the contributions to this special issue on trade-offs in corporate sustainability. Based on the framework, we finally point to some promising avenues for future research on trade-offs in, and a more inclusive notion of, corporate sustainability.

Searches for Lepton Flavor Violation in the Decays tau(+/-) -> e(+/-)gamma and tau(+/-) -> mu(+/-)gamma

Abstract: Searches for lepton-flavor-violating decays of a tau lepton to a lighter mass lepton and a photon have been performed with the entire data set of (963 +/- 7) x 10(6) tau decays collected by the BABAR detector near the Y(4S), Y(3S) and Y(2S) resonances. The searches yield no evidence of signals and we set upper limits on the branching fractions of B(tau(+/-) -> e(+/-)gamma) mu(+/-)gamma) < 4.4 X 10(-8) at 90% confidence level.

The Ontogeny of Plant Defense and Herbivory: Characterizing General Patterns Using Meta‐Analysis

Abstract: Defense against herbivores often changes dramatically as plants develop. Hypotheses based on allocation theory and herbivore selection patterns predict that defense should increase or decrease, respectively, across ontogeny, and previous research partly supports both predictions. Thus, it remains unclear which pattern is more common and what factors contribute to variability among studies. We conducted a meta-analysis of 116 published studies reporting ontogenetic patterns in plant defense traits and herbivory. Patterns varied depending on plant life form (woody, herbaceous, grass), type of herbivore (insect, mollusk, mammal), and type of defense trait (secondary chemistry, physical defense, tolerance). In woody plants, chemical defense increased during the seedling stage, followed by an increase in physical defenses during the vegetative juvenile stage. Mammalian herbivores showed a strong preference for mature compared to juvenile tissues in woody plants. Herbs experienced a significant increase in secondary chemistry across the entire ontogenetic trajectory, although the magnitude of increase was greatest during the seedling stage. Correspondingly, mollusks preferred young compared to older herbs. Future research investigating growth/defense trade-offs, allometry, herbivore selection patterns, and ecological costs would shed light on the mechanisms driving the ontogenetic patterns observed.

The Cognitive Interview: A meta-analytic review and study space analysis of the past 25 years.

Abstract: The Cognitive Interview (CI) is a well-established protocol for interviewing wit- nesses The current article presents a study space analysis of laboratory studies of the CI together with an empirical meta-analysis summarizing the past 25 years of research The study space comprises 57 published articles (65 experiments) on the CI, providing an assessment of the boundary conditions underlying the analysis and application of this interview protocol The current meta-analysis includes 46 pub- lished articles, including 20 articles published since the last meta-analysis conducted a decade earlier (Kohnken, Milne, Memon, & Bull, 1999) Reassuringly for prac- titioners, the findings of the original meta-analysis were replicated with a large and significant increase in correct details and a small increase in errors In addition we found that there were no differences in the rate at which details are confabulated Importantly, the effect sizes were unaffected by the inclusion of recent studies using modified versions of the CI The CI appeared to benefit older adult witnesses even more than younger adults We highlight trends and gaps in research and discuss how our findings can inform policy and training decisions The Cognitive Interview (or CI) is perhaps one of the most successful developments in psychology and law research in the last 25 years It is a method that comprises a series of memory retrieval and communication techniques designed to increase the amount of information that can be obtained from an interviewee The CI was initially developed 25 years ago by psychologists Ed Geiselman and Ron Fisher as a response to the many requests they received from police officers and legal professionals for a method of improving witness inter- views It is based upon established psychological principles of remembering and retrieval of information from memory, and empirical laboratory research on the CI has documented its ability to dramatically improve the number of correct details while only slightly increasing the number of incorrect details (Schrieber & Fisher, 2006; Kohnken et al, 1999; Memon, 2006) Field tests of the CI have also indicated that police officers trained in its techniques gain more information and

Prejudice and truth about the effect of testosterone on human bargaining behaviour.

Abstract: Both biosociological and psychological models, as well as animal research, suggest that testosterone has a key role in social interactions. Evidence from animal studies in rodents shows that testosterone causes aggressive behaviour towards conspecifics. Folk wisdom generalizes and adapts these findings to humans, suggesting that testosterone induces antisocial, egoistic, or even aggressive human behaviours. However, many researchers have questioned this folk hypothesis, arguing that testosterone is primarily involved in status-related behaviours in challenging social interactions, but causal evidence that discriminates between these views is sparse. Here we show that the sublingual administration of a single dose of testosterone in women causes a substantial increase in fair bargaining behaviour, thereby reducing bargaining conflicts and increasing the efficiency of social interactions. However, subjects who believed that they received testosterone-regardless of whether they actually received it or not-behaved much more unfairly than those who believed that they were treated with placebo. Thus, the folk hypothesis seems to generate a strong negative association between subjects' beliefs and the fairness of their offers, even though testosterone administration actually causes a substantial increase in the frequency of fair bargaining offers in our experiment.

Asymptotic formulae for likelihood-based tests of new physics

Abstract: We describe likelihood-based statistical tests for use in high energy physics for the discovery of new phenomena and for construction of confidence intervals on model parameters. We focus on the properties of the test procedures that allow one to account for systematic uncertainties. Explicit formulae for the asymptotic distributions of test statistics are derived using results of Wilks and Wald. We motivate and justify the use of a representative data set, called the "Asimov data set", which provides a simple method to obtain the median experimental sensitivity of a search or measurement as well as fluctuations about this expectation.

Fluvial form in modern continental sedimentary basins: Distributive fluvial systems

Abstract: Analysis of more than 700 modern continental sedimentary basins that are both endorheic (internally drained) and exorheic (externally drained) and cover a wide range of climatic and tectonic settings shows that sedimentation is dominated by distributive fluvial systems (DFSs). Facies distributions on DFSs are different from those of rivers in degradational settings, yet rivers in non-aggradational settings are commonly used to develop fluvial facies models. DFS rivers typically decrease in size downstream, are not confined to valleys, and form a radial pattern from an apex. Confined rivers are present in specific locations in sedimentary basins, including basin axial positions, areas between adjacent DFSs, and valleys incised into the DFS. DFSs and adjacent axial fluvial systems develop in a predictable manner that allows interpretation and prediction of fluvial architecture at the basin scale.

Hands only illusion: multisensory integration elicits sense of ownership for body parts but not for non-corporeal objects

Abstract: The experience of body ownership can be successfully manipulated during the rubber hand illusion using synchronous multisensory stimulation. The hypothesis that multisensory integration is both a necessary and sufficient condition for body ownership is debated. We systematically varied the appearance of the object that was stimulated in synchrony or asynchrony with the participant’s hand. A viewed object that was transformed in three stages from a plain wooden block to a wooden hand was compared to a realistic rubber hand. Introspective and behavioural results show that participants experience a sense of ownership only for the realistic prosthetic hand, suggesting that not all objects can be experienced as part of one’s body. Instead, the viewed object must fit with a reference model of the body that contains important structural information about body parts. This body model can distinguish between corporeal and non-corporeal objects, and it therefore plays a critical role in maintaining a coherent sense of one’s body.

Large Distributive Fluvial Systems: Characteristics, Distribution, and Controls on Development

Abstract: An analysis of remotely sensed imagery reveals that fluvial planform geometries within aggrading continental areas are dominated by distributive fluvial systems (DFSs). We documented the gradient, length, apex location, planform, termination type, and tectonic and climatic setting of 415 examples of fluvial systems which in planform display a radial, distributive channel pattern and have an apex–toe distance > 30 km (large DFSs). The longest of these DFSs is 704 km in length, with the majority (72%) ranging between 30 and 100 km in length. Gradients on individual systems range from 0.00003 (0.0018°) to 0.02656 (1.5°). Six planform types are recognized, those with: (1) a single braided channel that bifurcates downstream into braided and/or straight channels, (2) a single dominant braided channel, (3) a single dominant braided channel which becomes sinuous downstream often bifurcating, (4) a single dominant sinuous channel, (5) a single sinuous channel that bifurcates downstream into smaller sinuous channels, and (6) multiple sinuous channels. Of the studied examples 58% occur within exorheic basins and 42% in endorheic basins, with seven different termination types recognized. In many examples, channel planform changes downstream from a distributive pattern to a contributory pattern. In others, channels terminate at an axial fluvial system, at the coast, in eolian dune fields, playa lakes, permanent lakes, or wetlands. Large DFSs and their catchments are developed in all climatic regimes, including drylands, tropical, subtropical, continental, and polar climates. Large DFSs occur in all tectonic settings, including extensional, compressional, strike-slip, and cratonic tectonic regimes. General trends and relationships between the different studied parameters can be observed, leading to a broad understanding of the main controls on large DFS development. All of the planform types occur in all tectonic settings and all climate zones. Braided planforms dominate all tectonic settings, but particularly compressional regimes. High-gradient braided systems tend to be associated with areas of high relief and are well developed in dryland climates where discharge is inferred to be intermittent in comparison to tropical climates. Large DFSs with sinuous planforms do occur in dryland climates but tend to predominate in wetter, more tropical climates where discharge is more constant and the fluvial systems can distribute bedload more efficiently. Sinuous systems also tend to have significantly lower gradients than braided systems. Although these general observations can be made, there are significant variations from these trends, which are inferred to be controlled by variations in (1) discharge related to climate and (2) sediment supply, which is a function of climate, catchment size, catchment lithology, and catchment relief. Large DFS length is controlled by the available horizontal accommodation space, which in turn is strongly related to tectonic setting. The longest DFSs occur in peripheral foreland basins and cratonic settings where lateral systems can develop across an extensive basinwards slope. Extensional, strike-slip, and piggy-back basins are narrower and have much more limited horizontal accommodation space. Consequently DFSs developed in these settings are shorter, with radii often less than 30 km. DFSs dominate in aggradational settings such as actively subsiding sedimentary basins and therefore form a significant proportion of alluvial sedimentary successions preserved in the rock record.

International differences in IFRS policy choice: A research note

Abstract: Building on literature that suggests motives and opportunities for national versions of IFRS practice, we examine whether there are systematic differences in IFRS accounting policies between countries. Using information from the annual reports of companies in the blue chip indices of the largest five stock markets that use IFRS, we reject a null hypothesis that IFRS practice is the same across countries. For 16 accounting policy issues, we find instead significant evidence that pre‐ IFRS national practice continues where this is allowed within IFRS. By this, we document the existence of national patterns of accounting within IFRS. We also point out some policy implications that arise from our findings.

Surface deformation and slab–mantle interaction during Banda arc subduction rollback

Abstract: The reason for the spectacular curvature of the Banda subduction zone is debated. Tomographic images and plate reconstructions reveal subduction of a single slab. The ancient geometry of the Australian plate, as well as the interaction between the slab and the mantle, caused the deformation of the slab. The spectacularly curved Banda arc comprises young oceanic crust1,2 enclosed by a volcanic inner arc, outer arc islands and a trough parallel to the Australian continental margin3,4,5. Strong seismic activity in the upper mantle defines a folded surface6,7, for which there are two contrasting explanations: deformation of a single slab5,8 or two separate slabs subducting from the north and south6,9. Here we combine seismic tomography with the plate tectonic evolution of the region to infer that the Banda arc results from subduction of a single slab. Our palaeogeographic reconstruction shows that a Jurassic embayment, which consisted of dense oceanic lithosphere enclosed by continental crust, once existed within the Australian plate. Banda subduction began about 15 million years ago when active Java subduction tore eastwards into the embayment. The present morphology of the subducting slab is only partially controlled by the shape of the embayment. As the Australian plate moved northward at a high speed of about 7 cm yr−1, the Banda oceanic slab rolled back towards the south–southeast accompanied by active delamination separating the crust from the denser mantle. Increasing resistance of the mantle to plate motion progressively folded the slab and caused strong deformation of the crust. The Banda arc represents an outstanding example of large-scale deformation of the Earth’s crust in response to coupling between the crust, slab and surrounding mantle.

Phanerozoic concentrations of atmospheric oxygen reconstructed from sedimentary charcoal

Abstract: Varying concentrations of atmospheric oxygen have affected the development of animals and the role of wildfire in ecosystems. Reconstructions of past oxygen concentrations from fossil charcoal constrain atmospheric oxygenation over the past 400 million years. Variations of the Earth’s atmospheric oxygen concentration (pO2) are thought to be closely tied to the evolution of life, with strong feedbacks between uni- and multicellular life and oxygen1,2. On the geologic timescale, pO2 is regulated by the burial of organic carbon and sulphur, as well as by weathering3. Reconstructions of atmospheric O2 for the past 400 million years have therefore been based on geochemical models of carbon and sulphur cycling4,5,6. However, these reconstructions vary widely4,5,6,7,8,9,10, particularly for the Mesozoic and early Cenozoic eras. Here we show that the abundance of charcoal in mire settings is controlled by pO2, and use this proxy to reconstruct the concentration of atmospheric oxygen for the past 400 million years. We estimate that pO2 was continuously above 26% during the Carboniferous and Permian periods, and that it declined abruptly around the time of the Permian–Triassic mass extinction. During the Triassic and Jurassic periods, pO2 fluctuated cyclically, with amplitudes up to 10% and a frequency of 20–30 million years. Atmospheric oxygen concentrations have declined steadily from the middle of the Cretaceous period to present-day values of about 21%. We conclude, however, that variation in pO2 was not the main driver of the loss of faunal diversity during the Permo–Triassic and Triassic–Jurassic mass extinction events.

Parasite and host assemblages: embracing the reality will improve our knowledge of parasite transmission and virulence

Abstract: Interactions involving several parasite species (multi-parasitized hosts) or several host species (multi-host parasites) are the rule in nature. Only a few studies have investigated these realistic, but complex, situations from an evolutionary perspective. Consequently, their impact on the evolution of parasite virulence and transmission remains poorly understood. The mechanisms by which multiple infections may influence virulence and transmission include the dynamics of intrahost competition, mediation by the host immune system and an increase in parasite genetic recombination. Theoretical investigations have yet to be conducted to determine which of these mechanisms are likely to be key factors in the evolution of virulence and transmission. In contrast, the relationship between multi-host parasites and parasite virulence and transmission has seen some theoretical investigation. The key factors in these models are the trade-off between virulence across different host species, variation in host species quality and patterns of transmission. The empirical studies on multi-host parasites suggest that interspecies transmission plays a central role in the evolution of virulence, but as yet no complete picture of the phenomena involved is available. Ultimately, determining how complex host-parasite interactions impact the evolution of host-parasite relationships will require the development of cross-disciplinary studies linking the ecology of quantitative networks with the evolution of virulence.

ICT4WHAT?—Using the choice framework to operationalise the capability approach to development

Abstract: Identifying the particular contribution of information and communication technologies (ICTs) to specific development goals has proven to be extremely difficult. This paper argues that instead of trying to make ICTs fit with a linear conceptualisation of impacts and an often economistic view of development, the field of information and communication technologies for development (ICT4D) should be used as a prime example of a development process which has to be analysed in a systemic and holistic way. Amartya Sen's capability approach offers a way of thinking about development not as economic growth, but as individual freedom. The Choice Framework is presented as a way of operationalising this approach and visualising the elements of a systemic conceptualisation of the development process. An individual case study, related to telecentres in rural Chile, is used to demonstrate the way the Choice Framework can be applied as a guide to a systemic and holistic analysis. Copyright © 2010 John Wiley & Sons, Ltd.

Knowledge sharing in organisational contexts: a motivation‐based perspective

Abstract: Purpose – Facilitating knowledge sharing within organisations is a difficult task: the willingness of individuals to share and integrate their knowledge is one of the central barriers. This paper aims to develop a motivation‐based perspective to explore how organisations resolve the social dilemma of knowledge sharing.Design/methodology/approach – The analysis builds on a three‐category taxonomy of motivation, adding “hedonic” motivation to the traditional dichotomy of “extrinsic” and “intrinsic” motivation. It uses case studies gleaned from the literature to explore the interactive effects between the different motivators in two different types of knowledge‐intensive organisations: professional bureaucracy and operating adhocracy.Findings – Within a professional bureaucracy, the social dilemma of knowledge sharing may be overcome through normative motivation, with provision of hedonic motivation through extrinsic incentives such as training and career progression. In an operating adhocracy where interdep...

Traditional accountants and business professionals: Portraying the accounting profession after Enron

Abstract: Society’s perception of the legitimacy of the accounting profession and its members is grounded in the verbal and visual images of accountants that are projected not only by accountants themselves but also by the media. The paper uses the critical literature on stereotypes to examine how books written for a general readership on Enron and other recent corporate failures portray accountants and accounting, and the implications their authors draw for corporate governance and the survival of the financial system. The paper explores how commentators have analyzed the changing activities of accountants (including the rise of consulting) and have contrasted the personalities of “founding fathers” of the US accounting profession with their early 21st-century successors. The paper concludes that changing stereotypes of accountants are evidence of “negative signals of movement” for accounting as a profession.