The role of social media in promoting special events: acceptance of Facebook ‘events’

This study examines Facebook ‘events’ as a medium for promoting special events to consumers. This study proposes a Social Technology Acceptance Model, an extension of the TAM model, to examine the influence of trust, expected relationships and perceived enjoyment in forming consumer attitudes towards Facebook and consumers intentions to attend an event. Data was collected through an online survey administered through special event organizer’s Facebook ‘Pages’. Findings of the study suggest that users’ trust and expected relationship through Facebook had a significant effect on users’ acceptance of Facebook and their intended offline behaviour to attend the event. Practical and theoretical implications are discussed

Large non-Gaussianities in the Effective Field Theory Approach to Single-Field Inflation: the Bispectrum

The methods of effective field theory are used to study generic theories of inflation with a single inflaton field and to perform a general analysis of the associated non-Gaussianities. We investigate the amplitudes and shapes of the various generic three-point correlators, the bispectra, which may be generated by different classes of single-field inflationary models. Besides the well-known results for the DBI-like models and the ghost inflationary theories, we point out that curvature-related interactions may give rise to large non-Gaussianities in the form of bispectra characterized by a flat shape which, quite interestingly, is independently produced by several interaction terms. In a subsequent work, we will perform a similar general analysis for the non-Gaussianities generated by the generic four-point correlator, the trispectrum.Comment: Version matching the one published in JCAP, 2 typos fixed, references added. 30 pages, 20 figure

A parton picture of de Sitter space during slow-roll inflation

It is well-known that expectation values in de Sitter space are afflicted by infra-red divergences. Long ago, Starobinsky proposed that infra-red effects in de Sitter space could be accommodated by evolving the long-wavelength part of the field according to the classical field equations plus a stochastic source term. I argue that--when quantum-mechanical loop corrections are taken into account--the separate-universe picture of superhorizon evolution in de Sitter space is equivalent, in a certain leading-logarithm approximation, to Starobinsky's stochastic approach. In particular, the time evolution of a box of de Sitter space can be understood in exact analogy with the DGLAP evolution of partons within a hadron, which describes a slow logarithmic evolution in the distribution of the hadron's constituent partons with the energy scale at which they are probed.Comment: 36 pages; uses iopart.cls and feynmp.sty. v2: Minor typos corrected. Matches version published in JCA

Large non-Gaussianities in the Effective Field Theory Approach to Single-Field Inflation: the Trispectrum

We perform the analysis of the trispectrum of curvature perturbations generated by the interactions characterizing a general theory of single-field inflation obtained by effective field theory methods. We find that curvature-generated interaction terms, which can in general give an important contribution to the amplitude of the four-point function, show some new distinctive features in the form of their trispectrum shape-function. These interesting interactions are invariant under some recently proposed symmetries of the general theory and, as shown explicitly, do allow for a large value of the trispectrum.Comment: 29 pages, 13 figure

Signatures of Planck-scale interactions in the cosmic microwave background?

Based on a rather general low-energy effective action (interacting quantum fields in classical curved space-times), we calculate potential signatures of new physics (such as quantum gravity) at ultra-high energies (presumably the Planck scale) in the anisotropies of the cosmic microwave background. These Planck-scale interactions create non-Gaussian contributions, where special emphasis is laid on the three-point function as the most promising observable, which also allows the discrimination between models violating and those obeying Lorentz invariance. PACS: 98.80.Cq, 04.62.+v, 98.70.Vc, 98.80.Qc.Comment: 4 page

Infectious disease screening outcomes and reducing barriers to care for unaccompanied asylum-seeking children: a single centre retrospective clinical analysis

Objective: Evaluate the Unity Clinic’s infectious disease screening programme for unaccompanied asylum-seeking children (UASC), calculate rates of infection and identify further health needs. Design: Retrospective audit of electronic patient data. Setting and patients UASC who attended the Unity Clinic between 1 November 2019 and 22 March 2022. Main outcome measures: Baseline demographics, social, mental health and journey details, infection screening and investigation results. Results: 155 UASC were reviewed: 89% (138 of 155) male, median age 17 years (IQR 16–17). Most frequent countries of origin were Sudan, Eritrea and Afghanistan. Median duration of travel to the UK (n=79) was 2 years (IQR 0.5–4); 35.6% (47 of 132) arrived by boat and 54.5% (72 of 132) by road. 44.8% (69 of 154) had one or more positive infection screening results: 22.7% (35 of 154) and 1.3% (2 of 154) positive for latent and active tuberculosis, respectively; 4.6% (7 of 152) chronic active hepatitis B and 17.1% (26 of 152) for past infection; 1.3% (2 of 154) for HIV; 13.0% (19 of 146) for Strongyloides. There were three cases of syphilis (n=152; 2.0%) and one chlamydia (n=148; 0.7%)—none of whom disclosed prior sexual activity during screening. 39.6% (61 of 154) and 27.9% (43/154) reported disturbances to mood or sleep, respectively. 55.2% (85 of 154) disclosed traumatic incidents during and/or prior to their journey, including physical and sexual assault. Conclusions: The Unity Clinic provides a thorough infectious disease screening service for UASC following national guidance. Results highlight the need for universal, non-judgemental screening for sexually transmitted infections, as targeted screening would not identify positive cases. High rates of well-being issues and previous abuse emphasise the need for multidisciplinary, collaborative approaches to care

Infrared effects in inflationary correlation functions

In this article, I briefly review the status of infrared effects which occur when using inflationary models to calculate initial conditions for a subsequent hot, dense plasma phase. Three types of divergence have been identified in the literature: secular, "time-dependent" logarithms, which grow with time spent outside the horizon; "box-cutoff" logarithms, which encode a dependence on the infrared cutoff when calculating in a finite-sized box; and "quantum" logarithms, which depend on the ratio of a scale characterizing new physics to the scale of whatever process is under consideration, and whose interpretation is the same as conventional field theory. I review the calculations in which these divergences appear, and discuss the methods which have been developed to deal with them.Comment: Invited review for focus section of Classical & Quantum Gravity on nonlinear and nongaussian perturbation theory. Some improvements compared to version which will appear in CQG, especially in Sec. 2.3. 30 pages + references