Systematics of Moduli Stabilization, Inflationary Dynamics and Power Spectrum

We study the scalar sector of type IIB superstring theory compactified on Calabi-Yau orientifolds as a place to find a mechanism of inflation in the early universe. In the large volume limit, one can stabilize the moduli in stages using perturbative method. We relate the systematics of moduli stabilization with methods to reduce the number of possible inflatons, which in turn lead to a simpler inflation analysis. Calculating the order-of-magnitude of terms in the equation of motion, we show that the methods are in fact valid. We then give the examples where these methods are used in the literature. We also show that there are effects of non-inflaton scalar fields on the scalar power spectrum. For one of the two methods, these effects can be observed with the current precision in experiments, while for the other method, the effects might never be observable.Comment: 20 pages, JHEP style; v.2 and v.3: typos fixed, discussion and references adde

Sparticle Spectra and LHC Signatures for Large Volume String Compactifications

We study the supersymmetric particle spectra and LHC collider observables for the large-volume string models with a fundamental scale of 10^{11} GeV that arise in moduli-fixed string compactifications with branes and fluxes. The presence of magnetic fluxes on the brane world volume, required for chirality, perturb the soft terms away from those previously computed in the dilute-flux limit. We use the difference in high-scale gauge couplings to estimate the magnitude of this perturbation and study the potential effects of the magnetic fluxes by generating many random spectra with the soft terms perturbed around the dilute flux limit. Even with a 40% variation in the high-scale soft terms the low-energy spectra take a clear and predictive form. The resulting spectra are broadly similar to those arising on the SPS1a slope, but more degenerate. In their minimal version the models predict the ratios of gaugino masses to be M_1 : M_2 : M_3=(1.5 - 2) : 2 : 6, different to both mSUGRA and mirage mediation. Among the scalars, the squarks tend to be lighter and the sleptons heavier than for comparable mSUGRA models. We generate 10 fb^{-1} of sample LHC data for the random spectra in order to study the range of collider phenomenology that can occur. We perform a detailed mass reconstruction on one example large-volume string model spectrum. 100 fb^{-1} of integrated luminosity is sufficient to discriminate the model from mSUGRA and aspects of the sparticle spectrum can be accurately reconstructed.Comment: 42 pages, 21 figures. Added references and discussion for section 3. Slight changes in the tex

Flamelet/flow interaction in premixed turbulent flames - Simultaneous measurements of gas velocity and flamelet position

An experimental technique for obtaining simultaneous measurements of fluid velocity and flamelet position in premixed flames is described and applied in a turbulent V-flame. The flamelet position information is used to calculate conditional velocity statistics, conditional on both zone (reactants or products) as well as conditional on distance from the flamelet. The conditional zone statistics demonstrate that increases (or decreases) in turbulence across the flame are dependent on axial position and location within the flame brush. The product- zone conditional covariance, coupled with the measured conditional mean velocity profiles, indicate that turbulence generation by shear may be a significant contribution to product zone turbulence levels. Velocity statistics conditional on distance from the flamelet demonstrate a considerable interaction between the flamelet and velocity field. Man and rms velocities vary significantly with proximity to the flamelet, such that differences in velocities which which occur just across the flamelet surface. The change in rms velocities just across the flamelet is found to be anisotropic, with the largest increase (smallest decrease) occurring in the axial velocity component. Rms velocities conditional on flamelet position further support the hypothesis that increased product gas velocity fluctuations may have a significant component associated with turbulence generation by mean shear

Learning from the experience of peer support facilitators and study nurses in diabetes peer support: a qualitative study

Objectives We report on the experiences of peer support facilitators and study nurses who participated in a large trial of peer support for type 2 diabetes. The support was led by volunteer peer support facilitators, who were trained in overcoming barriers to diabetes care, motivational interviewing, listening skills and setting up and running group support sessions. There is currently a distinct lack of qualitative evidence on what works in peer support. Methods The peer support facilitators and study nurses completed open-answer questionnaire items on what worked well and less well, problems encountered and how they were resolved, group dynamics and suggestions for improvement. We also collected data from end-of-study meetings. Inductive thematic analysis was used to allow the emergent themes to be strongly based in the data. Findings: We find that process factors, peer support facilitator and peer characteristics, their relationships with each other and group dynamics are all fundamental for effective peer support. Sustaining and ending support also emerged as a key theme. Discussion Given the increasing interest in peer support, these findings will be useful to those interested in running groups in the future. Training programmes should help peer support facilitators develop confidence whilst emphasising that peer support ideally entails an equal, democratic dynamic. More attention is needed on to how to end groups appropriately

Does job crafting affect employee outcomes via job characteristics? A meta‐analytic test of a key job crafting mechanism

Job crafting refers to the self-initiated work behaviours employees use to change their job characteristics. According to job design theory, these crafting-induced changes in job characteristics should impact employee outcomes. Job characteristics can therefore be proposed as a key mechanism through which job crafting affects employee outcomes and we present cross-sectional meta-analytic structural equation modelling of this key mechanism (K = 58 independent samples, N = 20,347 employees). Results show significant indirect effects between task resource crafting and employee outcomes (well-being and positive job attitudes) via task resources, and significant indirect effects between social job crafting and employee outcomes (well-being and positive job attitudes) via social resources. Results also indicated that challenge and hindrance demand crafting increase job strain via increases in job demand. Overall, our findings indicate that job characteristics are an important job crafting mechanism, that employees may have difficulty in crafting job demands in ways that produce beneficial outcomes, and that future research needs to consider simultaneously the range of mechanisms through which job crafting affects outcomes

Phenomenology of a Pseudo-Scalar Inflaton: Naturally Large Nongaussianity

Many controlled realizations of chaotic inflation employ pseudo-scalar axions. Pseudo-scalars \phi are naturally coupled to gauge fields through c \phi F \tilde{F}. In the presence of this coupling, gauge field quanta are copiously produced by the rolling inflaton. The produced gauge quanta, in turn, source inflaton fluctuations via inverse decay. These new cosmological perturbations add incoherently with the "vacuum" perturbations, and are highly nongaussian. This provides a natural mechanism to generate large nongaussianity in single or multi field slow-roll inflation. The resulting phenomenological signatures are highly distinctive: large nongaussianity of (nearly) equilateral shape, in addition to detectably large values of both the scalar spectral tilt and tensor-to-scalar ratio (both being typical of large field inflation). The WMAP bound on nongaussianity implies that the coupling, c, of the pseudo-scalar inflaton to any gauge field must be smaller than about 10^{2} M_p^{-1}.Comment: 45 pages, 7 figure

Seriation and Multidimensional Scaling: A Data Analysis Approach to Scaling Asymmetric Proximity Matrices

A number of model-based scaling methods have been developed that apply to asymmetric proximity matrices. A flexible data analysis approach is pro posed that combines two psychometric procedures— seriation and multidimensional scaling (MDS). The method uses seriation to define an empirical order ing of the stimuli, and then uses MDS to scale the two separate triangles of the proximity matrix defined by this ordering. The MDS solution con tains directed distances, which define an "extra" dimension that would not otherwise be portrayed, because the dimension comes from relations between the two triangles rather than within triangles. The method is particularly appropriate for the analysis of proximities containing temporal information. A major difficulty is the computa tional intensity of existing seriation algorithms, which is handled by defining a nonmetric seriation algorithm that requires only one complete itera tion. The procedure is illustrated using a matrix of co-citations between recent presidents of the Psychometric Society.Yeshttps://us.sagepub.com/en-us/nam/manuscript-submission-guideline

Accidental Inflation in the Landscape

We study some aspects of fine tuning in inflationary scenarios within string theory flux compactifications and, in particular, in models of accidental inflation. We investigate the possibility that the apparent fine-tuning of the low energy parameters of the theory needed to have inflation can be generically obtained by scanning the values of the fluxes over the landscape. Furthermore, we find that the existence of a landscape of eternal inflation in this model provides us with a natural theory of initial conditions for the inflationary period in our vacuum. We demonstrate how these two effects work in a small corner of the landscape associated with the complex structure of the Calabi-Yau manifold P^4_[1,1,1,6,9] by numerically investigating the flux vacua of a reduced moduli space. This allows us to obtain the distribution of observable parameters for inflation in this mini-landscape directly from the fluxes.Comment: 40 pages, 11 figure

Managing groundwater supplies subject to drought: perspectives on current status and future priorities from England (UK)

Effective management of groundwater resources during drought is essential. How is groundwater currently managed during droughts, and in the face of environmental change, what should be the future priorities? Four themes are explored, from the perspective of groundwater management in England (UK): (1) integration of drought definitions; (2) enhanced fundamental monitoring; (3) integrated modelling of groundwater in the water cycle; and (4) better information sharing. Whilst these themes are considered in the context of England, globally, they are relevant wherever groundwater is affected by drought

Topology from Cosmology

We show that cosmological observables can constrain the topology of the compact additional dimensions predicted by string theory. To do this, we develop a general strategy for relating cosmological observables to the microscopic parameters of the potentials and field-dependent kinetic terms of the multiple scalar fields that arise in the low-energy limit of string theory. We apply this formalism to the Large Volume Scenarios in Type IIB flux compactifications where analytical calculations are possible. Our methods generalize to other settings