Sustained lower incidence of thyroid cancer in West Cumbria, UK

Background: In recent years, incidences of thyroid cancer have increased in developed countries; one of the known risk factors for thyroid cancer is exposure to radioiodine. Previous research by Bowlt and Tiplady [5] has shown an inverse link between radioactive iodine levels contained in thyroid tissue of deceased inhabitants and the distance they lived from the Sellafield nuclear facility in Cumbria, UK. Objectives: The present study aimed to determine what thyroid cancer incidences were in the regional localities in Cumbria for the last decade. Methods: An ethics-approved retrospective cohort study in which age-standardised incidence of thyroid cancer per 100,000 population was compared between localities within Cumbria and with UK average figures. Conclusions: The present study shows that the apparent lower incidence of thyroid cancer in West Cumbria has persisted, although due to the limited number of thyroid cancers diagnosed, a statistically significant difference was not observed. Further research – potentially involving populations living near sources of radioiodine emission - is indicated to investigate if there are any mechanisms that underlie this apparent trend

Red nuggets grow inside-out: evidence from gravitational lensing

We present a new sample of strong gravitational lens systems where both the foreground lenses and background sources are early-type galaxies. Using imaging from HST/ACS and Keck/NIRC2, we model the surface brightness distributions and show that the sources form a distinct population of massive, compact galaxies at redshifts $0.4 \lesssim z \lesssim 0.7$, lying systematically below the size-mass relation of the global elliptical galaxy population at those redshifts. These may therefore represent relics of high-redshift red nuggets or their partly-evolved descendants. We exploit the magnifying effect of lensing to investigate the structural properties, stellar masses and stellar populations of these objects with a view to understanding their evolution. We model these objects parametrically and find that they generally require two S\'ersic components to properly describe their light profiles, with one more spheroidal component alongside a more envelope-like component, which is slightly more extended though still compact. This is consistent with the hypothesis of the inside-out growth of these objects via minor mergers. We also find that the sources can be characterised by red-to-blue colour gradients as a function of radius which are stronger at low redshift -- indicative of ongoing accretion -- but that their environments generally appear consistent with that of the general elliptical galaxy population, contrary to recent suggestions that these objects are predominantly associated with clusters.Comment: 21 pages; accepted for publication in MNRA

Stellar Parameters for HD 69830, a Nearby Star with Three Neptune Mass Planets and an Asteroid Belt

We used the CHARA Array to directly measure the angular diameter of HD 69830, home to three Neptune mass planets and an asteroid belt. Our measurement of 0.674+/-0.014 milli-arcseconds for the limb-darkened angular diameter of this star leads to a physical radius of R$_*$ = 0.9058$\pm$0.0190 R\sun and luminosity of L* = 0.622+/-0.014 Lsun when combined with a fit to the spectral energy distribution of the star. Placing these observed values on an Hertzsprung-Russel (HR) diagram along with stellar evolution isochrones produces an age of 10.6+/-4 Gyr and mass of 0.863$\pm$0.043 M\sun. We use archival optical echelle spectra of HD 69830 along with an iterative spectral fitting technique to measure the iron abundance ([Fe/H]=-0.04+/-0.03), effective temperature (5385+/-44 K) and surface gravity (log g = 4.49+/-0.06). We use these new values for the temperature and luminosity to calculate a more precise age of 7.5+/-Gyr. Applying the values of stellar luminosity and radius to recent models on the optimistic location of the habitable zone produces a range of 0.61-1.44 AU; partially outside the orbit of the furthest known planet (d) around HD 69830. Finally, we estimate the snow line at a distance of 1.95+/-0.19 AU, which is outside the orbit of all three planets and its asteroid belt.Comment: 5 pages, 3 figures, accepted to Ap

Prevalence of HPV infection and other risk factors in a Fijian population.

BACKGROUND: Cancer is among the leading contributors to morbidity and mortality in the Pacific, but the magnitude of the problem and the potential for prevention have not been comprehensively studied. Over the past decade, cervical cancer has been the most common cancer among women in Fiji with an age standardised cervical cancer incidence rate of 51 per 100,000. This rate is among the highest in the South Pacific region and in the world. This high cervical cancer incidence rate is likely linked to the low cervical screening rate, but it points also to the possibility of a high burden of human papillomavirus (HPV) infection. METHODS: We conducted a population-based survey in Fiji to provide information on human papillomavirus (HPV) prevalence, and the distribution of individual HPV types in a Fijian health-sub-district. We included 1,261 women aged between 16 and 64 years. A general primer GP5+/6+ mediatedpolymerase chain reaction (PCR) assay was used for HPV testing of 44 HPV types. RESULTS: The crude HPV prevalence in 1,244 women with an adequate HPV sample was 24.0% (95% confidence interval (CI), 21.7-26.4%) and the corresponding age standardised prevalence was 25.5% (95% CI, 23.1-28.1%). The prevalence of high-risk HPV types was 13.6% (95% CI, 11.8-15.6%). Among 1,192 women with adequate cytological results, 13 (1.1%) showed cervical abnormalities, the majority of which were high-grade intraepithelial lesions or worse. HPV prevalence declined from 35.8% in women aged <25 years to 18.6% in those aged 55-64 years of age. After adjustment, the only variables significantly associated with HPV-positivity were age (ranging from odds ratio (OR) 0.57 (95% CI, 0.36-0.89) for 25-34 year-old-women to OR 0.43 (95% CI, 0.20-0.89) for 55-64 year-old-women) and 'husband's extramarital sexual relationships' (OR 1.69; 95% CI, 1.17-2.34). CONCLUSION: These findings on HPV provide key information for future policy decisions on the most appropriate methods of cervical cancer prevention in Fiji and in the Pacific region

Planet Hunters VII. Discovery of a New Low-Mass, Low-Density Planet (PH3 c) Orbiting Kepler-289 with Mass Measurements of Two Additional Planets (PH3 b and d)

We report the discovery of one newly confirmed planet ($P=66.06$ days, $R_{\rm{P}}=2.68\pm0.17R_\oplus$) and mass determinations of two previously validated Kepler planets, Kepler-289 b ($P=34.55$ days, $R_{\rm{P}}=2.15\pm0.10R_\oplus$) and Kepler-289-c ($P=125.85$ days, $R_{\rm{P}}=11.59\pm0.10R_\oplus$), through their transit timing variations (TTVs). We also exclude the possibility that these three planets reside in a $1:2:4$ Laplace resonance. The outer planet has very deep ($\sim1.3$), high signal-to-noise transits, which puts extremely tight constraints on its host star's stellar properties via Kepler's Third Law. The star PH3 is a young ($\sim1$ Gyr as determined by isochrones and gyrochronology), Sun-like star with $M_*=1.08\pm0.02M_\odot$, $R_*=1.00\pm0.02R_\odot$, and $T_{\rm{eff}}=5990\pm38$ K. The middle planet's large TTV amplitude ($\sim5$ hours) resulted either in non-detections or inaccurate detections in previous searches. A strong chopping signal, a shorter period sinusoid in the TTVs, allows us to break the mass-eccentricity degeneracy and uniquely determine the masses of the inner, middle, and outer planets to be $M=7.3\pm6.8M_\oplus$, $4.0\pm0.9M_\oplus$, and $M=132\pm17M_\oplus$, which we designate PH3 b, c, and d, respectively. Furthermore, the middle planet, PH3 c, has a relatively low density, $\rho=1.2\pm0.3$ g/cm$^3$ for a planet of its mass, requiring a substantial H/He atmosphere of $2.1^{+0.8}_{-0.3}$ by mass, and joins a growing population of low-mass, low-density planets.Comment: 21 pages, 10 figures, 5 tables, accepted into Ap

Planet Hunters. V. A Confirmed Jupiter-Size Planet in the Habitable Zone and 42 Planet Candidates from the Kepler Archive Data

We report the latest Planet Hunter results, including PH2 b, a Jupiter-size (R_PL = 10.12 \pm 0.56 R_E) planet orbiting in the habitable zone of a solar-type star. PH2 b was elevated from candidate status when a series of false positive tests yielded a 99.9% confidence level that transit events detected around the star KIC 12735740 had a planetary origin. Planet Hunter volunteers have also discovered 42 new planet candidates in the Kepler public archive data, of which 33 have at least three transits recorded. Most of these transit candidates have orbital periods longer than 100 days and 20 are potentially located in the habitable zones of their host stars. Nine candidates were detected with only two transit events and the prospective periods are longer than 400 days. The photometric models suggest that these objects have radii that range between Neptune to Jupiter. These detections nearly double the number of gas giant planet candidates orbiting at habitable zone distances. We conducted spectroscopic observations for nine of the brighter targets to improve the stellar parameters and we obtained adaptive optics imaging for four of the stars to search for blended background or foreground stars that could confuse our photometric modeling. We present an iterative analysis method to derive the stellar and planet properties and uncertainties by combining the available spectroscopic parameters, stellar evolution models, and transiting light curve parameters, weighted by the measurement errors. Planet Hunters is a citizen science project that crowd-sources the assessment of NASA Kepler light curves. The discovery of these 43 planet candidates demonstrates the success of citizen scientists at identifying planet candidates, even in longer period orbits with only two or three transit events.Comment: 35 pages, 11 figures, 6 tables, accepted and published on ApJ ApJ, 776, 1

Supramolecular self-assembled network formation containing N···Br halogen bonds in physisorbed overlayers.

The formation of a halogen bonded self-assembled co-crystal physisorbed monolayer containing N···Br interactions is reported for the first time. The co-crystal monolayer is identified experimentally by synchrotron X-ray diffraction and the structure determined. Density functional theory (DFT) calculations are also employed to assess the magnitudes of the different interactions in the layer. Significantly, compared to other halogen bonds in physisorbed monolayers we have reported recently, the N···Br bond here is found to be non-linear. It is proposed that the increasing importance of the lateral hydrogen bond interactions, relative to the halogen bond strength, leads to the bending of the halogen bonds.We acknowledge financial support for AB from EPSRC DTA award from the Department of Chemistry, University of Cambridge. We acknowledge Diamond Light Source for time on beamline I11 under proposals EE6511 and EE7761.This is the final version of the article. It first appeared from the Royal Society of Chemistry via http://dx.doi.org/10.1039/C4CP03379

A Global lake ecological observatory network (GLEON) for synthesising high-frequency sensor data for validation of deterministic ecological models

A Global Lake Ecological Observatory Network (GLEON; www.gleon.org) has formed to provide a coordinated response to the need for scientific understanding of lake processes, utilising technological advances available from autonomous sensors. The organisation embraces a grassroots approach to engage researchers from varying disciplines, sites spanning geographic and ecological gradients, and novel sensor and cyberinfrastructure to synthesise high-frequency lake data at scales ranging from local to global. The high-frequency data provide a platform to rigorously validate processbased ecological models because model simulation time steps are better aligned with sensor measurements than with lower-frequency, manual samples. Two case studies from Trout Bog, Wisconsin, USA, and Lake Rotoehu, North Island, New Zealand, are presented to demonstrate that in the past, ecological model outputs (e.g., temperature, chlorophyll) have been relatively poorly validated based on a limited number of directly comparable measurements, both in time and space. The case studies demonstrate some of the difficulties of mapping sensor measurements directly to model state variable outputs as well as the opportunities to use deviations between sensor measurements and model simulations to better inform process understanding. Well-validated ecological models provide a mechanism to extrapolate high-frequency sensor data in space and time, thereby potentially creating a fully 3-dimensional simulation of key variables of interest