3,762 research outputs found

    Natural Inflation: Particle Physics Models, Power Law Spectra for Large Scale Structure, and Constraints from COBE

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    A pseudo-Nambu-Goldstone boson, with a potential of the form V(ϕ)=Λ4[1±cos(ϕ/f)],naturallygivesrisetoinflationifV(\phi) = \Lambda^4[1 \pm \cos(\phi/f)], naturally gives rise to inflation if f \sim M_{Pl}and and \Lambda \sim M_{GUT}.Weshowhowthiscanariseintechnicolorlikeandsuperstringmodels,andworkoutanexplicitstringexampleinthecontextofmultiplegauginocondensationmodels.Westudythecosmologyofthismodelindetail,andfindthatsufficientreheatingtoensurethatbaryogenesiscantakeplacerequires. We show how this can arise in technicolor-like and superstring models, and work out an explicit string example in the context of multiple gaugino condensation models. We study the cosmology of this model in detail, and find that sufficient reheating to ensure that baryogenesis can take place requires f > 0.3 M_{Pl}.Theprimordialdensityfluctuationspectrumgeneratedisanonscaleinvariantpowerlaw,. The primordial density fluctuation spectrum generated is a non-scale-invariant power law, P(k) \propto k^{n_s},with, with n_s \simeq 1 - (M^2_{Pl}/8\pi f^2),leadingtomorepoweronlargelengthscalesthanthe, leading to more power on large length scales than the n_s = 1HarrisonZeldovichspectrum.ThestandardCDMmodelwith Harrison-Zeldovich spectrum. The standard CDM model with 0 \la n_s \la 0.6-0.7couldinprincipleexplainthelargescaleclusteringobservedintheAPMandIRASgalaxysurveysaswellaslargescaleflows,buttheCOBEmicrowaveanisotropyimpliessuchlowamplitudes(orhighbiasfactors, could in principle explain the large-scale clustering observed in the APM and IRAS galaxy surveys as well as large-scale flows, but the COBE microwave anisotropy implies such low amplitudes (or high bias factors, b>2)fortheseCDMmodelsthatgalaxyformationoccurstoolatetobeviable;combiningCOBEwithsufficientlyearlygalaxyformationorthelargescaleflowsleadsto) for these CDM models that galaxy formation occurs too late to be viable; combining COBE with sufficiently early galaxy formation or the large-scale flows leads to n_s >0.6,or, or f > 0.3 M_{Pl}aswell.Forextendedandpowerlawinflationmodels,thisconstraintiseventighter, as well. For extended and power law inflation models, this constraint is even tighter, n_s > 0.7$; combined with other bounds on large bubbles in extended inflation, this leaves little room for most extended models.Comment: 42 pages, (12 figures not included but available from the authors

    Towards a co-creation framework in the retail banking services industry: a cross-cultural analysis

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    An underlying theme in modern marketing is the notion that value is not solely created within the boundaries of the firm, it is created co-jointly with outside parties. This paper aims to study the outcomes of co-creation from a customer perspective. Specifically, it examines the effects of co-creation on customer satisfaction, loyalty and word-of-mouth (WOM) within the banking services industry. Furthermore, we consider potential differences between consumers from Spain and the UK, thus incorporating cross-cultural aspects in our research. The research demonstrates that firms should not only respond to the differences that exist within different cultural contexts and incorporate these in co-creation initiatives; more importantly, firms should undertake co-creation activities themselves as these can result in customers who are more satisfied, loyal to the company and more likely to carry out positive WOM, which can ultimately lead to new customers

    Effect on smoking quit rate of telling patients their lung age: the Step2quit randomised controlled trial

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    Objective To evaluate the impact of telling patients their estimated spirometric lung age as an incentive to quit smoking.Design Randomised controlled trial.Setting Five general practices in Hertfordshire, England.Participants 561 current smokers aged over 35.Intervention All participants were offered spirometric assessment of lung function. Participants in intervention group received their results in terms of "lung age" (the age of the average healthy individual who would perform similar to them on spirometry). Those in the control group received a raw figure for forced expiratory volume at one second (FEV1). Both groups were advised to quit and offered referral to local NHS smoking cessation services.Main outcome measures The primary outcome measure was verified cessation of smoking by salivary cotinine testing 12 months after recruitment. Secondary outcomes were reported changes in daily consumption of cigarettes and identification of new diagnoses of chronic obstructive lung disease.Results Follow-up was 89%. Independently verified quit rates at 12 months in the intervention and control groups, respectively, were 13.6% and 6.4% (difference 7.2%, P=0.005, 95% confidence interval 2.2% to 12.1%; number needed to treat 14). People with worse spirometric lung age were no more likely to have quit than those with normal lung age in either group. Cost per successful quitter was estimated at 280 pound ((euro) 365, $556). A new diagnosis of obstructive lung disease was made in 17% in the intervention group and 14% in the control group; a total of 16% (89/561) of participants.Conclusion Telling smokers their lung age significantly improves the likelihood of them quitting smoking, but the mechanism by which this intervention achieves its effect is unclear.Trial registration National Research Register N0096173751

    Modelling the neuromechanics of exploration and taxis in larval Drosophiila

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    The Drosophila larva is emerging as a useful tool in the study of complex behaviours, due to its relatively small size, its genetic tractability, and its varied behavioural repertoire. The larva executes a stereotypical exploratory routine that appears to consist of stochastic alternation between straight peristaltic crawling and reorientation events through lateral bending. The larva performs taxis by biasing this behavioural pattern, allowing it to move up or down attractive and aversive stimulus gradients. Existing explanations of exploration and taxis behaviour often neglect the larva's embodiment, focusing on central pattern generation and decision making circuits within the nervous system. In Chapter 1 of this thesis, I review the current state of knowledge regarding larval peristalsis, exploration, and taxis behaviours, as well as existing theories of their generation. I argue that an understanding of the animal's embodiment should lead to a deeper understanding of its behaviour. In Chapter 2, I present a model of the axial mechanics of the larva, and demonstrate how the animal's body physics can be exploited to produce peristalsis by using segmentally localised, positive feedback of strain rate. The mechanical model includes viscoelastic tissue mechanics, muscular inputs, and substrate interaction while sensory feedback is modelled as a linear feedback control law. In Chapter 3, I extend the mechanical model to study motion in the plane, including both axial and transverse deformations of the body. The feedback law is replaced by a simple model of the larval nervous system. The model includes both a segmentally localised reflex arc as well as long-range, mutual inhibition between segments. The complete model is capable of generating both peristalsis and spontaneous reorientation, leading to emergent exploration behaviour in the form of a deterministic superdiffusion process grounded in the chaotic mechanics of the larva's body. In Chapter 4, I consider taxis behaviour. I introduce a transverse reflex capable of modulating the effective transverse viscosity of the larval body. When the larva is experiencing an increasing attractive (aversive) stimulus, the reflex acts to increase (decrease) the effective transverse viscosity, causing bending to occur less (more) easily. As a result, the model larvae approach attractive stimuli and avoid aversive stumuli. On a population level, I show that the transverse reflex can be thought of as biasing the model animals towards sub- or super-diffusion. I compare the statistics of this behaviour to those of the real larva. In Chapter 5, I shift focus to engineered soft systems. Having successfully deployed an energy-based modelling approach in Chapters 2--4, I argue for the adoption of an energy-focused (specifically, port-Hamiltonian) approach within the field of soft robotics. In Chapter 6, I present some initial theoretical extensions to the models presented in chapter 2--4. I first focus on the mechanics of self-righting and rolling behaviours, before modelling the ventral nerve cord of the larva using a ring attractor architecture. Finally, in Chapter 7, I summarise the results of the previous chapters and discuss directions for future research

    ¿Demasiado Amor Obstaculiza la Innovación? Participación Familiar e Innovación de las Empresas en Pequeñas y Medianas Empresas (PYME) de Propiedad Familiar

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    Current literature suggests that family involvement has an impact on firm innovativeness, but it is not able to explain in which conditions. Adopting a curvilinear model, (Olson’s circumplex model of family) this research demonstrates that the family's cohesion and flexibility levels play a significant role in the relationship between family involvement and firm innovation propensity. This paper also provides evidence for the theory that previous research limitations are due to the fact that they posit a linear relationship between family involvement and innovativeness. Instead, the Circumplex curvilinear model shows a better fit for explaining the family involvement impact on innovation propensity.La literatura actual sugiere que la participación familiar tiene un impacto en la innovación empresarial, pero no puede explicar en qué condiciones. Adoptando un modelo curvilíneo (el modelo de familia circumplex de Olson) esta investigación demuestra que los niveles de cohesión y flexibilidad de la familia juegan un papel importante en la relación entre la participación familiar y la propensión a la innovación empresarial. Además, al investigar cuantitativamente una muestra de PYME (N = 125), este trabajo también muestra que un modelo curvilíneo muestra un mejor ajuste (en comparación con los modelos lineales) para explicar el impacto de la participación familiar en la propensión a la innovación. Finalmente, se discuten las implicaciones académicas y prácticas

    Hierarchical Complexity and Corporate Opaqueness

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    This thesis examines the impact of hierarchical complexity on corporate opaqueness and how this relationship varies under the moderating effect of corporate diversification, quality of the home country institutional environment and the host country institutional environment. I hypothesize that increases in firms’ hierarchical complexity are related to greater corporate opaqueness between the firm and outside investors on the capital market. Using a sample of US firms spanning 5 years from 2012 to 2016, I find a statistically and economically significant, positive relationship between hierarchical complexity and corporate opaqueness. The results of the thesis further imply that the impact of hierarchical complexity on opaqueness is alleviated when there is related corporate diversification and an increasing quality of the host country institutional environment.Thesis (Ph.D.) -- University of Adelaide, Business School, 201

    Measuring client modes of engagement in humanistic experiential psychotherapy

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    The role of clients' emotional engagement has progressively played a central role in psychotherapy. This project inserts itself in this debate by seeking to validate the Client Modes of Engagement (CME) theoretical model (Elliott 2006; 2013a). While Elliott's CME framework-a process-diagnostic map based on clients' experiential content-was grounded on decades of research and clinical practice, it had yet to be made amenable to empirical investigation.;This project responds to this absence by offering the Client Modes of Engagement Observational Coding System (CME-OCS) and the Client Modes of Engagement Questionnaire (CMEQ-R2). These instruments measure the construct from both the perspective of external observers (CME-OCS) and therapists (CMEQ-R2).;This dissertation explores the application and validation process for both the CME-OCS and the CMEQ-R2. The results confirmed that the CME-OCS is a reliable coding system for identifying CMEs during EFT psychotherapy. Additionally, the findings suggest that there are interactions between CMEs, phases of therapy, and outcome groups. Moreover, I established that there are differences in the ways outcome groups' transition between CMEs at particular stages of therapy.;I applied both classical psychometric properties methods and Rasch modelling with the purpose of examining the CMEQ-R2's psychometrics, refining the instrument, and later applying it in a process outcome study. The results suggest that levels of CME early in therapy and changes in levels of CME over therapy-as measured by the CMEQ-R2-are significantly associated with client pre-post therapeutic improvement.;I also found firm ground for arguing that therapists can distinguish between levels of CMEs and that their perspective can be systematically analysed. Together, both instruments pose important implications for research and clinical practice. Overall, this study validates the contention that researchers and therapists should be particularly attentive to clients' manner of engagement and focus of attention on specific levels of their emotion scheme.The role of clients' emotional engagement has progressively played a central role in psychotherapy. This project inserts itself in this debate by seeking to validate the Client Modes of Engagement (CME) theoretical model (Elliott 2006; 2013a). While Elliott's CME framework-a process-diagnostic map based on clients' experiential content-was grounded on decades of research and clinical practice, it had yet to be made amenable to empirical investigation.;This project responds to this absence by offering the Client Modes of Engagement Observational Coding System (CME-OCS) and the Client Modes of Engagement Questionnaire (CMEQ-R2). These instruments measure the construct from both the perspective of external observers (CME-OCS) and therapists (CMEQ-R2).;This dissertation explores the application and validation process for both the CME-OCS and the CMEQ-R2. The results confirmed that the CME-OCS is a reliable coding system for identifying CMEs during EFT psychotherapy. Additionally, the findings suggest that there are interactions between CMEs, phases of therapy, and outcome groups. Moreover, I established that there are differences in the ways outcome groups' transition between CMEs at particular stages of therapy.;I applied both classical psychometric properties methods and Rasch modelling with the purpose of examining the CMEQ-R2's psychometrics, refining the instrument, and later applying it in a process outcome study. The results suggest that levels of CME early in therapy and changes in levels of CME over therapy-as measured by the CMEQ-R2-are significantly associated with client pre-post therapeutic improvement.;I also found firm ground for arguing that therapists can distinguish between levels of CMEs and that their perspective can be systematically analysed. Together, both instruments pose important implications for research and clinical practice. Overall, this study validates the contention that researchers and therapists should be particularly attentive to clients' manner of engagement and focus of attention on specific levels of their emotion scheme

    Finding Thermal Forms:A Method and Model for Thermally Defined Masonry Structures

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    Bricks / Systems

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    Bricks and Sustainability

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