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Globular clusters exhibit abundance variations, defining `multiple populations', which have prompted a protracted search for their origin. Properties requiring explanation include: the high fraction of polluted stars ($\sim 40{-}90$~percent, correlated with cluster mass), the absence of pollution in young clusters and the lower pollution rate with binarity and distance from the cluster centre. We present a novel mechanism for late delivery of pollutants into stars via accretion of sub-stellar companions. In this scenario, stars move through a medium polluted with AGB and massive star ejecta, accreting material to produce companions with typical mass ratio $q\sim 0.1$. These companions undergo eccentricity excitation due to dynamical perturbations by passing stars, culminating in a merger with their host star. The accretion of the companion alters surface abundances via injected pollutant. Alongside other self-enrichment models, the companion accretion model can explain the dilution of pollutant and correlation with intra-cluster location. The model also explains the ubiquity and discreteness of the populations and correlations of enrichment rates with cluster mass, cluster age and stellar binarity. Abundance variations in some clusters can be broadly reproduced using AGB and massive binary ejecta abundances from the literature. In other clusters, some high companion mass ratios ($q\gtrsim 1$) are required. In these cases, the available mass budget necessitates a variable degree of mixing of the polluted material with the primary star, deviations from model ejecta abundances or mixing of internal burning products. We highlight the avenues of further investigation which are required to explore some of the key processes invoked in this model., Comment: 29 pages, 20 figures, accepted for publication in MNRAS

Planet-forming disc evolution is not independent of the star formation and feedback process in giant molecular clouds. In particular, OB stars emit UV radiation that heats and disperses discs in a process called 'external photoevaporation'. This process is understood to be the dominant environmental influence acting on planet-forming discs in typical star forming regions. Our best studied discs are nearby, in sparse stellar groups where external photoevaporation is less effective. However the majority of discs are expected to reside in much stronger UV environments. Understanding external photoevaporation is therefore key to understanding how most discs evolve, and hence how most planets form. Here we review our theoretical and observational understanding of external photoevaporation. We also lay out key developments for the future to address existing unknowns and establish the full role of external photoevaporation in the disc evolution and planet formation process., Comment: Review article accepted for publication in EPJ+ - 47 pages, 17 figures

Short period, massive planets, known as hot Jupiters (HJs), have been discovered around $\sim 1$ percent of local field stars. The inward migration necessary to produce HJs may be `low eccentricity', due to torques in the primordial disc, or `high eccentricity' (HEM). The latter involves exciting high orbital eccentricity, allowing sufficiently close passages with the host star to raise circularising tides in the planet. We present an analytic framework for quantifying the role of dynamical encounters in high density environments during HEM. We show that encounters can enhance or suppress HEM, depending on the local stellar density and the initial semi-major axis $a_0$. For moderate densities, external perturbations can excite large eccentricities that allow a planet to circularise over the stellar lifetime. At extremely high densities, these perturbations can instead result in tidal disruption of the planet, thus yielding no HJ. This may explain the apparent excess of HJs in M67 compared with their local field star abundance versus their apparent deficit in 47 Tuc. Applying our analytic framework, we demonstrate that for an initial massive planet population similar to the field, the expected HJ occurrence rate in 47 Tuc is $f_\mathrm{HJ}=2.2\times 10^{-3}$, which remains consistent with present constraints. Future large (sample sizes $\gtrsim 10^5$) or sensitive transit surveys of stars in globular clusters are required to refute the hypothesis that the initial planet population is similar to the solar neighbourhood average. Non-detection in such surveys would have broad consequences for planet formation theory, implying planet formation rates in globular clusters must be suppressed across a wide range of $a_0$., Accepted for publication in MNRAS - 28 pages, 17 figures

A recent survey of the inner $0.35\times0.35$pc of the NGC 2024 star forming region revealed two distinct millimetre continuum disc populations that appear to be spatially segregated by the boundary of a dense cloud. The eastern (and more embedded) population is $\sim0.2-0.5$Myr old, with an ALMA mm continuum disc detection rate of about $45\,$per cent. However this drops to only $\sim15$per cent in the 1Myr western population. When presenting this result, van Terwisga et al. (2020) suggested that the two main UV sources, IRS 1 (a B0.5V star in the western region) and IRS 2b (an O8V star in the eastern region, but embedded) have both been evaporating the discs in the depleted western population. In this paper we report the firm discovery in archival HST data of 4 proplyds and 4 further candidate proplyds in NGC 2024, confirming that external photoevaporation of discs is occurring. However, the locations of these proplyds changes the picture. Only three of them are in the depleted western population and their evaporation is dominated by IRS 1, with no obvious impact from IRS 2b. The other 5 proplyds are in the younger eastern region and being evaporated by IRS 2b. We propose that both populations are subject to significant external photoevaporation, which happens throughout the region wherever discs are not sufficiently shielded by the interstellar medium. The external photoevaporation and severe depletion of mm grains in the 0.2-0.5Myr eastern part of NGC 2024 would be in competition even with very early planet formation., Comment: 14 pages, Accepted for publication in MNRAS

We used the Atacama Pathfinder Experiment (APEX) telescope to search for CI 1-0 (492.16GHz) emission towards 8 proplyds in NGC 1977, which is an FUV radiation environment two orders of magnitude weaker than that irradiating the Orion Nebular Cluster (ONC) proplyds. CI is expected to enable us to probe the wind launching region of externally photoevaporating discs. Of the 8 targets observed, no 3$\sigma$ detections of the CI line were made despite reaching sensitivities deeper than the anticipated requirement for detection from prior APEX CI observations of nearby discs and models of external photoevaporation of quite massive discs. By comparing both the proplyd mass loss rates and CI flux constraints with a large grid of external photoevaporation simulations, we determine that the non-detections are in fact fully consistent with the models if the proplyd discs are very low mass. Deeper observations in CI and probes of the disc mass with other tracers (e.g. in the continuum and CO) can test this. If such a test finds higher masses, this would imply carbon depletion in the outer disc, as has been proposed for other discs with surprisingly low CI fluxes, though more massive discs would also be incompatible with models that can explain the observed mass loss rates and CI non-detections. The expected remaining lifetimes of the proplyds are estimated to be similar to those of proplyds in the ONC at 0.1Myr. Rapid destruction of discs is therefore also a feature of common, intermediate UV environments., Comment: 10 pages. Accepted for publication in MNRAS

Stars in globular clusters formed and evolved in the most extreme environment: high density and low metallicity. If the formation of stars and planets are at all sensitive to environmental conditions, this should therefore be evident in globular clusters. Observations have indicated that hot Jupiters are at least an order of magnitude less prevalent in the central region of the globular cluster 47 Tucanae than in the field. In this work, we explore the claims in the literature for additional consequences for the low mass stellar initial mass function. Tidal capture, the mechanism that produces X-ray binaries in globular clusters, applies also to brown dwarfs (BDs). This process produces tight stellar-BD binaries that would be detectable by transit surveys. Applying a Monte Carlo dynamical evolution model, we compute the overall BD capture rates. We find that the number of captures is lower than previous estimates. Capture efficiency increases steeply with stellar mass, which means that mass segregation reduces capture efficiency as BDs and low mass stars occupy the same regions. The result of this effect is that the current constraints on the short period companion fraction remains marginally consistent with initially equal numbers of BDs and stars. However, our findings suggest that expanding the sample in 47 Tuc or surveying other globular clusters for close sub-stellar companions can yield constraints on the sub-stellar initial mass function in these environments. We estimate the capture rates in other globular clusters and suggest that 47 Tuc remains a promising target for future transit surveys., 15 pages, 13 figures, accepted for publication in MNRAS

INTRODUCTION: As gonococcal infections continue to increase, we wanted to review the number and clinical course of recent ocular gonococcal cases presenting to ophthalmology departments in NHS Greater Glasgow and Clyde. METHODS: A 5-year retrospective review of adult ocular gonococcal cases, where the diagnosis of Neisseria gonorrhoeae was made on microbiological culture, was undertaken. RESULTS: Fifteen cases were identified (80% male). Average age was 26 years (range 17–42; median 24). Most common presenting features included purulent discharge (14/15; 93%), haemorrhagic conjunctivitis (10/15; 67%) and pre-septal cellulitis (9/15; 60%). Corneal involvement was documented in 5 (33%), with marginal ulceration in 1 (7%) but none had corneal perforation. Most common systemic treatment was IV ceftriaxone, alone or in combination with another antibiotic (6/15; 40%), followed by IM ceftriaxone, alone or in combination with another antibiotic (5/15; 33%). Median time from presentation to treatment was 1 day (0–23). All patients were referred or recommended to attend sexual health services. Seven patients (47%) attended and received complete sexually transmitted infection (STI) testing and contact tracing: 3 patients had systemic treatment initiated or changed at this visit and 1 patient had concurrent syphilis identified. CONCLUSIONS: This series confirms purulent conjunctivitis and cellulitis as the main presenting features of ocular gonococcal infection requiring hospital review. Early identification with appropriate systemic antibiotic treatment avoided corneal melting in this cohort. As concurrent STIs were identified and/or treatments changed in 4/7 (57%) following sexual health review, we recommend a shared care approach between ophthalmology, microbiology and sexual health services to effectively address all management issues.

Tidal encounters in star clusters perturb discs around young protostars. In Cuello et al. (2019a, Paper I) we detailed the dynamical signatures of a stellar flyby in both gas and dust. Flybys produce warped discs, spirals with evolving pitch angles, increasing accretion rates, and disc truncation. Here we present the corresponding observational signatures of these features in optical/near-infrared scattered light and (sub-) millimeter continuum and CO line emission. Using representative prograde and retrograde encounters for direct comparison, we post-process hydrodynamical simulations with radiative transfer methods to generate a catalogue of multi-wavelength observations. This provides a reference to identify flybys in recent near-infrared and sub-millimetre observations (e.g., RW Aur, AS 205, HV Tau & DO Tau, FU Ori, V2775 Ori, and Z CMa)., 11 pages, 5 figures, accepted for publication in MNRAS

Protoplanetary discs (PPDs) in the Orion Nebula Cluster (ONC) are irradiated by UV fields from the massive star $��^1$C. This drives thermal winds, inducing mass loss rates of up to $\dot{M}_\mathrm{wind}\sim 10^{-7}\,M_\odot$/yr in the `proplyds' (ionised PPDs) close to the centre. For the mean age of the ONC and reasonable initial PPD masses, such mass loss rates imply that discs should have been dispersed. However, ~80% of stars still exhibit a NIR excess, suggesting that significant circumstellar mass remains. This `proplyd lifetime problem' has persisted since the discovery of photoevaporating discs in the core of the ONC by O'Dell & Wen (1994). In this work, we demonstrate how an extended period of star formation can solve this problem. Coupling N-body calculations and a viscous disc evolution model, we obtain high disc fractions at the present day. This is partly due to the migration of older stars outwards, and younger stars inwards such that the most strongly irradiated PPDs are also the youngest. We show how the disc mass distribution can be used to test the recent claims in the literature for multiple stellar populations in the ONC. Our model also explains the recent finding that host mass and PPD mass are only weakly correlated, in contrast with other regions of similar age. We conclude that the status of the ONC as the archetype for understanding the influence of environment on planet formation is undeserved; the complex star formation history (involving star formation episodes within ~0.8 Myr of the present day) results in confusing signatures in the PPD population., 16 pages, 11 figures, accepted for publication in MNRAS

Many stars form in regions of enhanced stellar density, wherein the influence of stellar neighbours can have a strong influence on a protoplanetary disc (PPD) population. In particular, far ultraviolet (FUV) flux from massive stars drives thermal winds from the outer edge of PPDs, accelerating disc destruction. In this work, we present a novel technique for constraining the dynamical history of a star forming environment using PPD properties in a strongly FUV irradiated environment. Applying recent models for FUV induced mass loss rates to the PPD population of Cygnus OB2, we constrain how long ago primordial gas was expelled from the region; $ 0.5$ Myr ago if the Shakura & Sunyaev $\alpha$-viscosity parameter is $\alpha = 10^{-2}$ (corresponding to a viscous timescale of $\tau_\mathrm{visc} \approx 0.5$ Myr for a disc of scale radius $40$ au around a $1\, M_\odot$ star). This value of $\alpha$ is effectively an upper limit, since it assumes efficient extinction of FUV photons throughout the embedded phase. With this gas expulsion timescale we are able to produce a full dynamical model that fits kinematic and morphological data as well as disc fractions. We suggest Cygnus OB2 was originally composed of distinct massive clumps or filaments, each with a stellar mass $\sim 10^4 \, M_\odot$. Finally we predict that in regions of efficient FUV induced mass loss, disc mass $M_\mathrm{disc}$ as a function of stellar host mass $m_\mathrm{star}$ follows a power law with $M_\mathrm{disc} \propto m_\mathrm{star}^\beta$, where $\beta \gtrsim 2.7$ (depending on disc initial conditions and FUV exposure). This is steeper than observed correlations in regions of moderate FUV flux ($1 < \beta, Comment: 20 pages, 17 figures, accepted by MNRAS

The exotic range of known planetary systems has provoked an equally exotic range of physical explanations for their diverse architectures. However, constraining formation processes requires mapping the observed exoplanet population to that which initially formed in the protoplanetary disc. Numerous results suggest that (internal or external) dynamical perturbation alters the architectures of some exoplanetary systems. Isolating planets that have evolved without any perturbation can help constrain formation processes. We consider the Kepler multiples, which have low mutual inclinations and are unlikely to have been dynamically perturbed. We apply a modelling approach similar to that of Mulders et al. (2018), additionally accounting for the two-dimensionality of the radius ($R =0.3-20\,R_\oplus$) and period ($P= 0.5-730$ days) distribution. We find that an upper limit in planet mass of the form $M_{\rm{lim}} \propto a^\beta \exp(-a_{\rm{in}}/a)$, for semi-major axis $a$ and a broad range of $a_{\rm{in}}$ and $\beta$, can reproduce a distribution of $P$, $R$ that is indistinguishable from the observed distribution by our comparison metric. The index is consistent with $\beta= 1.5$, expected if growth is limited by accretion within the Hill radius. This model is favoured over models assuming a separable PDF in $P$, $R$. The limit, extrapolated to longer periods, is coincident with the orbits of RV-discovered planets ($a>0.2$ au, $M>1\,M_{\rm{J}}$) around recently identified low density host stars, hinting at isolation mass limited growth. We discuss the necessary circumstances for a coincidental age-related bias as the origin of this result, concluding that such a bias is possible but unlikely. We conclude that, in light of the evidence that some planetary systems have been dynamically perturbed, simple models for planet growth during the formation stage are worth revisiting., Comment: 21 pages, 16 figures, accepted for publication in MNRAS

Massive stars are strong sources of far-ultraviolet radiation that can be hostile to the evolution of protoplanetary disks, driving mass loss by external photoevaporation and shortening disk-dissipation timescales. Their effect may also reduce the timescale of angular momentum exchanges between the disk and host star during the early pre-main-sequence phase. To improve our understanding of the environmental influence on the rotational history of stars, we developed a model that considers the influence of the local far-ultraviolet radiation on the spin evolution of low mass stars. Our model includes an assumption of disk-locking, which fixes the rotation rate during the star-disk-interaction phase, with the duration of this phase parametrised as a function of the local far-ultraviolet radiation and stellar mass (in the range 0.1--1.3 M$_\odot$). In this way, we demonstrate how the feedback from massive stars can significantly influence the spin evolution of stars and explain the mass-dependency observed in period-mass distributions of young regions like Upper Sco and NGC 2264. The high far-ultraviolet environments of high-mass stars can skew the period distribution of surrounding stars towards fast-rotation, explaining the excess of fast-rotating stars in the open cluster h Per. The proposed link between rotation and the pre-main-sequence environment opens new avenues for interpreting the rotational distributions of young stars. For example, we suggest that stellar rotation may be used as a tracer for the primordial ultraviolet irradiation for stars up to $\sim$1 Gyr, which offers a potential method to connect mature planetary systems to their birth environment., Comment: 20 pages, 7 figures. Submitted to MNRAS

We study the time evolution of molecular clouds across three Milky Way-like isolated disc galaxy simulations at a temporal resolution of 1 Myr, and at a range of spatial resolutions spanning two orders of magnitude in spatial scale from ~10 pc up to ~1 kpc. The cloud evolution networks generated at the highest spatial resolution contain a cumulative total of ~80,000 separate molecular clouds in different galactic-dynamical environments. We find that clouds undergo mergers at a rate proportional to the crossing time between their centroids, but that their physical properties are largely insensitive to these interactions. Below the gas disc scale-height, the cloud lifetime obeys a scaling relation of the form $\tau_{\rm life} \propto \ell^{-0.3}$ with the cloud size $\ell$, consistent with over-densities that collapse, form stars, and are dispersed by stellar feedback. Above the disc scale-height, these self-gravitating regions are no longer resolved, so the scaling relation flattens to a constant value of ~13 Myr, consistent with the turbulent crossing time of the gas disc, as observed in nearby disc galaxies., Comment: Accepted to MNRAS

INTRODUCTION: Since 2007, the ocular 4:1 multiplex PCR assay in NHS Greater Glasgow and Clyde includes Chlamydia trachomatis (ocular chlamydia (OC)) testing. OC can be identified following routine ‘viral’ ophthalmic testing, including in asymptomatic patients. A published audit from 2008 identified only 25% of our OC patients attended and completed sexual health management, particularly when ophthalmologists initiated treatment. We subsequently created a shared care network between ophthalmology, virology and sexual health (including a designated sexual health advisor) to address these clinical issues. METHODS: A 10-year retrospective service review audit from January 2010 to December 2019 was performed to evaluate this approach. RESULTS: A total of 86 patients were identified (49 males (57%), median age 23 years (range 16–77)). Ophthalmologists initiated treatment for 37 patients (43%) prior to onward sexual health referral. Of this group, 5 (13.5%) received sub-optimal treatments, and 15 (40.5%) subsequently failed to attend sexual health services for partner notification. Of the 49 (57%) patients who attended sexual health, 25 (51%) had genital chlamydia co-infection, and 98% received adequate systemic treatment. All were offered full sexual health screening and 46 (93.9%) completed partner notification. CONCLUSIONS: This shared care approach more than doubled the proportion of OC patients attending sexual health services over this 10-year period (previously 25%, now 57%). Ophthalmologists could defer treatment to sexual health for more effective OC management; however, challenges remain to address real-world issues of non-attendance, inadequate treatment and incomplete contact tracing. We recommend a multi-disciplinary approach to best manage OC cases identified following ophthalmic testing.

Planet formation is generally described in terms of a system containing the host star and a protoplanetary disc, of which the internal properties (e.g. mass and metallicity) determine the properties of the resulting planetary system. However, (proto)planetary systems are predicted and observed to be affected by the spatially-clustered stellar formation environment, either through dynamical star-star interactions or external photoevaporation by nearby massive stars. It is challenging to quantify how the architecture of planetary systems is affected by these environmental processes, because stellar groups spatially disperse within, 69 pages, 13 Figures, accepted for publication in Nature

The stellar birth environment can significantly shorten protoplanetary disc (PPD) lifetimes due to the influence of stellar feedback mechanisms. The degree to which these mechanisms suppress the time and mass available for planet formation is dependent on the local far-ultraviolet (FUV) field strength, stellar density, and ISM properties. In this work, we present the first theoretical framework quantifying the distribution of PPD dispersal time-scales as a function of parameters that describe the galactic environment. We calculate the probability density function for FUV flux and stellar density in the solar neighbourhood. In agreement with previous studies, we find that external photoevaporation is the dominant environment-related factor influencing local stellar populations after the embedded phase. Applying our general prescription to the Central Molecular Zone of the Milky Way (i.e. the central ~250 pc), we predict that 90% of PPDs in the region are destroyed within 1 Myr of the dispersal of the parent molecular cloud. Even in such dense environments, we find that external photoevaporation is the dominant disc depletion mechanism over dynamical encounters between stars. PPDs around low-mass stars are particularly sensitive to FUV-induced mass loss, due to a shallower gravitational potential. For stars of mass ~1 $M_\odot$, the solar neighbourhood lies at approximately the highest gas surface density for which PPD dispersal is still relatively unaffected by external FUV photons, with a median PPD dispersal timescale of ~4 Myr. We highlight the key questions to be addressed to further contextualise the significance of the local galactic environment for planet formation., Comment: 22 pages, 12 figures; accepted for publication in MNRAS

The majority of stars form in a clustered environment. This has an impact on the evolution of surrounding protoplanetary discs (PPDs) due to either photoevaporation or tidal truncation. Consequently, the development of planets depends on formation environment. Here we present the first thorough investigation of tidally induced angular momentum loss in PPDs in the distant regime, partly motivated by claims in the literature for the importance of distant encounters in disc evolution. We employ both theoretical predictions and dynamical/hydrodynamical simulations in 2D and 3D. Our theoretical analysis is based on that of Ostriker (1994) and leads us to conclude that in the limit that the closest approach distance $x_{min} \gg r$, the radius of a particle ring, the fractional change in angular momentum scales as $(x_{min}/r)^{-5}$. This asymptotic limit ensures that the cumulative effect of distant encounters is minor in terms of its influence on disc evolution. The angular momentum transfer is dominated by the $m=2$ Lindblad resonance for closer encounters and by the $m=1$, $\omega = 0$ Lindblad resonance at large $x_{min}/r$. We contextualise these results by comparing expected angular momentum loss for the outer edge of a PPD due to distant and close encounters. Contrary to the suggestions of previous works we do not find that distant encounters contribute significantly to angular momentum loss in PPDs. We define an upper limit for closest approach distance where interactions are significant as a function of arbitrary host to perturber mass ratio $M_2/M_1$., Comment: 14 pages, 11 figures

Most stars form and spend their early life in regions of enhanced stellar density. Therefore the evolution of protoplanetary discs (PPDs) hosted by such stars are subject to the influence of other members of the cluster. Physically, PPDs might be truncated either by photoevaporation due to ultraviolet flux from massive stars, or tidal truncation due to close stellar encounters. Here we aim to compare the two effects in real cluster environments. In this vein we first review the properties of well studied stellar clusters with a focus on stellar number density, which largely dictates the degree of tidal truncation, and far ultraviolet (FUV) flux, which is indicative of the rate of external photoevaporation. We then review the theoretical PPD truncation radius due to an arbitrary encounter, additionally taking into account the role of eccentric encounters that play a role in hot clusters with a 1D velocity dispersion $\sigma_v > 2$ km/s. Our treatment is then applied statistically to varying local environments to establish a canonical threshold for the local stellar density ($n_{c} > 10^4$ pc$^{-3}$) for which encounters can play a significant role in shaping the distribution of PPD radii over a timescale $\sim 3$ Myr. By combining theoretical mass loss rates due to FUV flux with viscous spreading in a PPD we establish a similar threshold for which a massive disc is completely destroyed by external photoevaporation. Comparing these thresholds in local clusters we find that if either mechanism has a significant impact on the PPD population then photoevaporation is always the dominating influence., ERC Advanced Grant grant agreement 341137

Theory and observations suggest that star formation occurs hierarchically due to the fragmentation of giant molecular clouds. In this case we would expect substructure and enhanced stellar multiplicity in the primordial cluster. This substructure is expected to decay quickly in most environments, however historic stellar encounters might leave imprints in a protoplanetary disc (PPD) population. In a low density environment such as Taurus, tidal tails from violent star-disc or disc-disc encounters might be preserved over time-scales sufficient to be observed. In this work, we investigate the possibility that just such an event occured between HV Tau C (itself a component of a triple system) and DO Tau $\sim 0.1$ Myr ago, as evidenced by an apparent `bridge' structure evident in the $160$ $\mu$m emission. By modelling the encounter using smoothed particle hydrodynamics (SPH) we reproduce the main features of the observed extended structure (`V'-shaped emission pointing west of HV Tau and a tail-like structure extending east of DO Tau). We suggest that HV Tau and DO Tau formed together in a quadruple system on a scale of $\sim 5000$ au ($0.025$ pc)., Comment: 11 pages, 8 figures, accepted by MNRAS

We present an open access grid of 3930 calculations of externally evaporating protoplanetary discs. This spans a range of disc sizes (1-400AU), disc masses, UV field strengths (10-10$^4$G$_0$) and stellar masses (0.05-1.9M$_\odot$). The grid is publicly available for download, and offers a means of cheaply including external photoevaporation in disc evolutionary calculations. It can also be queried using an online tool for quick estimates of instantaneous mass loss rates (e.g for convenient evaluation of real observed systems). The `FRIED' grid itself illustrates that for discs around stars $\leq0.3$M$_\odot$ external photoevaporation is effective down to small radii ($, 16 pages, 9 figures. Accepted for publication in MNRAS

We describe ongoing work on the modelling, verification, and implementation of Integrated Care Pathways (ICPs) for HIV patients in Scotland. Healthcare knowledge, including existing policies, guidelines, and best practices, is encoded in formal, process - based, workflow models. This is achieved through the use of our logic - based, modelling framework WorkflowFM, which provides high levels of rigour and trust about the designed ICPs. We believe this effort will result in a formally verified, easily maintainable, computer based implementation of HIV ICPs that will greatly improve the current standard of care.

Introduction Implementation of an in-house polymerase chain reaction (PCR) multiplex assay by West of Scotland Specialist Virology Centre to improve sample processing means all viral eye swabs are now routinely tested for Adenovirus, Herpes simplex, Varicella and Chlamydia. Concern was raised regarding subsequent management and sexual health attendance for Chlamydia-positive patients identified in eye casualty. Methods A retrospective review of virology results identified 76 Chlamydia-positive patients from 1914 eye swabs (4%) from May 2007 to April 2008. Of these results, 12 originated from Glasgow eye casualty and available clinical notes were cross-referenced with the sexual health network (Sandyford). Results Identified issues included no documentation of implications of testing, poor communication of positive results and poor referral pathways to sexual health for assessment; all leading to inadequate management. A shared care network was created to address these issues. A designated sexual health advisor was identified to improve sexual health referral, specialist assessment, standardised management and contact tracing. Re-audit showed more consistent follow-up. Conclusion New PCR technology has resulted in a shared care approach to address corresponding implications of testing. Effective communication with a structured protocol and a central point of contact has improved follow-up and ensures appropriate best practice management of chlamydial conjunctivitis.

This edited collection provides a unique insight into sexual health in Scotland. It sets out the challenges facing Scotland in terms of poor sexual health and inequalities, within devolved government arrangements and a different healthcare system from the rest of the UK. It suggests that these factors have facilitated the development of an integrated model of sexual health planning and delivery with resonance beyond Scotland. Chapter authors include clinical specialists, managers and policy-makers, academics and senior government officials from Scotland and other parts of the UK, all of whom have an active role in commissioning, delivering or commenting upon sexual health services or sexual health. Both editors have significant experience in developing, delivering and managing innovative sexual and reproductive health services and have held national and international leadership and advisory roles concerning health policy and service management. They were instrumental in developing and delivering Sandyford, NHS Greater Glasgow and Clyde’s sexual health service – the largest in the UK and viewed as the UK leader in progressive service development

The concluding chapter in this section of the book provides a comprehensive review of the evolution of the Scottish sexual health patient information system - NaSH, and its eventual implementation. With all NHS Health Boards, at the time of writing, either using or about to introduce NaSH, this is a significant achievement, given the previous patchy nature of sexual health patient records in Scotland as the chapter describes. Dr Winter, a GUM consultant and expert in sexual health information management, was part of the group behind the NaSH system, and conveys the multiple strands that NaSH needed to incorporate, and the internal and external challenges that needed to be overcome. The NaSH system was funded by the Scottish Government to support increased access to services and to bring all sexual health services in Scotland into the 21st century in IT terms in line with the inception of the Sexual Health Strategy. It needed to meet the needs of national governance and local commissioners for robust information about client uptake, service efficiency and sexual health demographics; of clinicians and NHS managers for a workable and efficient system that maximised client outcomes; and of clients for a system that made services increasingly accessible yet protected confidentiality in a highly sensitive clinical area. The commissioning and tendering process for the NaSH system is described, and a range of tables and documents drawn from the development process included that illuminate the complexity of the system, and the issues that had to be addressed.

In 264 genitourinary medicine clinic attenders reporting recent fellatio, the prevalence of pharyngeal Chlamydia trachomatis determined by an expanded standard including cell culture and two in-house PCR tests was 1.5% in 194 women and zero in 70 men. The ligase chain reaction (Abbott LCx) had a specificity of 99.2% and a positive predictive value of 60%.

Background Acutely deranged liver function tests (LFTs) in HIV positive pregnant women present challenges in balancing pregnancy-related conditions, antiretroviral (ARVs) toxicities and prevention of mother to child transmission (MTCT). A 34 year old HIV positive lady with a history of poor engagement in care, psychosis, cognitive impairment and recent nevirapine resistance was admitted at 26 weeks gestation under mental health legislation due to cognitive impairment and self-neglect. Method She was commenced on darunavir/ritonavir 600 mg bd, truvada and raltegravir but three weeks later, at 29 weeks gestation, she developed rapidly progressive hepatic transaminitis. Abdominal ultrasound scan was normal and tests for viral hepatitis negative. Pre-eclampsia was excluded, leaving three working diagnoses: drug-induced hepatitis, obstetric cholestasis or acute fatty liver of pregnancy. ARVs were stopped but transaminases continued to rise (ALT 614 and AST 716 U/L). Clotting screen and platelet count remained normal but the patient began to complain of epigastric pain. HIV viral load had risen to 241 copies/ml. In view of deteriorating maternal health and the increasing risk of MTCT (HIV viral load expected to rise), the baby was delivered at 31 weeks’ gestation by semi-elective caesarean after a course of antenatal steroids. The baby received antiviral prophylaxis in the form of abacavir, lamivudine and zidovudine; HIV RNA was undetectable at three months (MTCT extremely unlikely). Nine days after delivery the patient’s LFTs normalised. Conclusion Darunavir-induced hepatitis typically presents with increased AST and ALT. In this case, LFTs only started to improve following delivery of the baby, suggesting a pregnancy related cause.

EDITOR—Hargreave and Mills failed sufficiently to emphasise the importance of sexually transmitted infections in their review on investigating and managing infertility in general practice.1 Genital tract infection with Chlamydia trachomatis is a major risk factor for subsequent tubal infertility.2 Many episodes of tubal infection can be asymptomatic3; those patients who have appreciable pelvic inflammation are …

Protoplanetary disk surveys by the Atacama Large Millimeter/sub-millimeter Array (ALMA) are now probing a range of environmental conditions, from low-mass star-forming regions like Lupus to massive OB clusters like $\sigma$ Orionis. Here we conduct an ALMA survey of protoplanetary disks in $\lambda$ Orionis, a ~5 Myr old OB cluster in Orion, with dust mass sensitivities comparable to the surveys of nearby regions (~0.4 $M_\oplus$). We assess how massive OB stars impact planet formation, in particular from the supernova that may have occurred ~1 Myr ago in the core of $\lambda$ Orionis; studying these effects is important as most planetary systems, including our Solar System, are likely born in cluster environments. We find that the effects of massive stars, in the form of pre-supernova feedback and/or a supernova itself, do not appear to significantly reduce the available planet-forming material otherwise expected at the evolved age of $\lambda$ Orionis. We also compare a lingering massive "outlier" disk in $\lambda$ Orionis to similar systems in other evolved regions, hypothesizing that these outliers host companions in their inner disks that suppress disk dispersal to extend the lifetimes of their outer primordial disks. We conclude with numerous avenues for future work, highlighting how $\lambda$ Orionis still has much to teach us about perhaps one of the most common types of planet-forming environments in the Galaxy., Comment: 21 pages, 8 figures, 3 tables. Accepted to AAS Journals