The Geoff Egan Memorial Lecture 2011. Artefacts, art and artifice: reconsidering iconographic sources for archaeological objects in early modern Europe

A first systematic analysis of historic domestic material culture depicted in contemporaneous Western painting and prints, c.1400-1800. Drawing on an extensive data set, the paper proposes to methodologies and hermeneutics for historical analysis and archaeological correspondence

Weak Lensing Determination of the Mass in Galaxy Halos

We detect the weak gravitational lensing distortion of 450,000 background galaxies (20<R<23) by 790 foreground galaxies (R<18) selected from the Las Campanas Redshift Survey (LCRS). This is the first detection of weak lensing by field galaxies of known redshift, and as such permits us to reconstruct the shear profile of the typical field galaxy halo in absolute physical units (modulo H_0), and to investigate the dependence of halo mass upon galaxy luminosity. This is also the first galaxy-galaxy lensing study for which the calibration errors are negligible. Within a projected radius of 200 \hkpc, the shear profile is consistent with an isothermal profile with circular velocity 164+-20 km/s for an L* galaxy, consistent with typical disk rotation at this luminosity. This halo mass normalization, combined with the halo profile derived by Fischer et al (2000) from lensing analysis SDSS data, places a lower limit of (2.7+-0.6) x 10^{12}h^{-1} solar masses on the mass of an L* galaxy halo, in good agreement with satellite galaxy studies. Given the known luminosity function of LCRS galaxies, and the assumption that $M\propto L^\beta$ for galaxies, we determine that the mass within 260\hkpc of normal galaxies contributes $\Omega=0.16\pm0.03$ to the density of the Universe (for $\beta=1$) or $\Omega=0.24\pm0.06$ for $\beta=0.5$. These lensing data suggest that $0.6<\beta<2.4$ (95% CL), only marginally in agreement with the usual $\beta\approx0.5$ Faber-Jackson or Tully-Fisher scaling. This is the most complete direct inventory of the matter content of the Universe to date.Comment: 18 pages, incl. 3 figures. Submitted to ApJ 6/7/00, still no response from the referee after four months

Development of an mHealth platform for HIV Care: gathering user perspectives through co-design workshops and interviews

Background: Despite advances in testing and treatment, HIV incidence rates within European countries are at best stable or else increasing. mHealth technology has been advocated to increase quality and cost-effectiveness of health services while dealing with growing patient numbers. However, studies suggested that mHealth apps are rarely adopted and often considered to be of low quality by users. Only a few studies (conducted in the United States) have involved people living with HIV (PLWH) in the design of mHealth. Objective: The goal of this study was to facilitate a co-design process among PLWH and clinicians across 5 clinical sites in the European Union to inform the development of an mHealth platform to be integrated into clinical care pathways. We aimed to (1) elicit experiences of living with HIV and of working in HIV care, (2) identify mHealth functionalities that are considered useful for HIV care, and (3) identify potential benefits as well as concerns about mHealth. Methods: Between January and June 2016, 14 co-design workshops and 22 semistructured interviews were conducted, involving 97 PLWH and 63 clinicians. Data were analyzed thematically and iteratively, drawing on grounded theory techniques. Results: Findings were established into 3 thematic clusters: (1) approaching the mHealth platform, (2) imagining the mHealth platform, and (3) anticipating the mHealth platform’s implications. Co-design participants approached the mHealth platform with pre-existing concerns arising from their experiences of receiving or providing care. PLWH particularly addressed issues of stigma and questioned how mHealth could enable them to manage their HIV. Clinicians problematized the compatibility of mHealth with existing information technology systems and questioned which patients should be targeted by mHealth. Imagining the potential of mHealth for HIV care, co-design participants suggested medical functionalities (accessing test results, managing medicines and appointments, and digital communication channels), social functionalities (peer support network, international travel, etc), and general features (security and privacy, credibility, language, etc). Co-design participants also anticipated potential implications of mHealth for self-management and the provision of care. Conclusions: Our approach to co-design enabled us to facilitate early engagement in the mHealth platform, enabling patient and clinician feedback to become embedded in the development process at a preprototype phase. Although the technologies in question were not yet present, understanding how users approach, imagine, and anticipate technology formed an important source of knowledge and proved highly significant within the technology design and development process

The X-ray Spectral Properties and Variability of Luminous High-Redshift Active Galactic Nuclei

We perform a detailed investigation of moderate-to-high quality X-ray spectra of ten of the most luminous active galactic nuclei (AGNs) known at z>4 (up to z~6.28). This study includes five new XMM observations and five archived X-ray observations (four by XMM and one by Chandra). We find that the X-ray power-law photon indices of our sample, composed of eight radio-quiet sources and two that are moderately radio loud, are not significantly different from those of lower redshift AGNs. The upper limits obtained on intrinsic neutral hydrogen column densities, N_H<~10^{22}-10^{23} cm^{-2}, indicate that these AGNs are not significantly absorbed. A joint fit performed on our eight radio-quiet sources, with a total of ~7000 photons, constrains the mean photon index of z>4 radio-quiet AGNs to Gamma=1.97^{+0.06}_{-0.04}, with no detectable intrinsic dispersion from source to source. We also obtain a strong constraint on the mean intrinsic column density, N_H<~3x10^{21} cm^{-2}, showing that optically selected radio-quiet AGNs at z>4 are, on average, not more absorbed than their lower-redshift counterparts. All this suggests that the X-ray production mechanism and the central environment in radio-quiet AGNs have not significantly evolved over cosmic time. The mean equivalent width of a putative neutral narrow Fe Ka line is constrained to be <~190 eV, and similarly we place constraints on the mean Compton reflection component (R<~1.2). None of the AGNs varied on short (~1 hr) timescales, but on longer timescales (months-to-years) strong variability is observed in four of the sources. In particular, the X-ray flux of the z=5.41 radio-quiet AGN SDSS 0231-0728 dropped by a factor of ~4 over a rest-frame period of 73 d. This is the most extreme X-ray variation observed in a luminous z>4 radio-quiet AGN.Comment: 10 pages (emulateapj), 5 figures. Accepted by Ap

Factors shaping attitudes towards UK bank brands: An exploratory analysis of social media data

Social media provides a huge amount of data and rich market insight, and has changed the way customers interact with brands. This interaction is of great concern for any organisation as it transfers the power to shape brand image from advertisers to consumers. In light of the global financial crisis and the ensuing negative attitudes towards bank brands, this study has extracted 1176 comments on bank advertisements from the verified Facebook pages of 10 UK banks. These comments have been thematically analysed to identify seven key factors that shape customer attitudes to bank brands. The study presents the power of social media as a platform for brands and customers to engage and build relationships, especially bank–customer relationships in the UK, providing managers with important insights that can guide the development and execution of their brand-relationship campaigns. The fact that this study is based on real-life advertisements and real-life responses from social media network users can be considered as one of its strengths, as it does not suffer from various issues relating to experimental studies. Nonetheless, the study’s limitations and suggestions for future research directions are provided