UHF Syledis for Coastal Survey Positioning

UHF positioning systems are intermediate between groundwave HF radio aids, such as Argo and Hi-Fix, and line-of-sight systems, such as Mini-Ranger III and Trisponder. The Canadian Hydrographic Service conducted tests along the coast of Nova Scotia in 1982/83 which showed that UHF propagation velocity is unaffected by the terrain that the signal passes over, that UHF Syledis is effective to about 100 km over water and low-lying land, and that low pressure weather systems reduce Syledis performance. This paper will describe test procedures and results, and the subsequent CHS experience with Syledis in the first year of operational use in 1983

Mapping the spectrum of psychological and behavioural responses to low-dose CT lung cancer screening offered within a Lung Health Check

BACKGROUND: Research on the psychological impact of low-dose computed tomography (LDCT) lung cancer screening has typically been narrow in scope and restricted to the trial setting. OBJECTIVE: To explore the range of psychological and behavioural responses to LDCT screening offered as part of a Lung Heath Check (LHC), including lung cancer risk assessment, spirometry testing, a carbon monoxide reading and smoking cessation advice. METHODS: Semi-structured interviews were carried out with 28 current and former smokers (aged 60-75), who had undergone LDCT screening as part of a LHC appointment and mostly received an incidental or indeterminate result (n = 23). Framework analysis was used to map the spectrum of responses participants had across the LHC appointment and screening pathway, to their LDCT results and to surveillance. RESULTS: Interviewees reported a diverse range of both positive and negative psychological responses, beginning at invitation and spanning the entire LHC appointment (including spirometry) and LDCT screening pathway. Similarly, positive behavioural responses extended beyond smoking cessation to include anticipated implications for other cancer prevention and early detection behaviours, such as symptom presentation. Individual differences in responses appeared to be influenced by smoking status and LDCT result, as well as modifiable factors including perceived risk and health status, social support, competing priorities, fatalism and perceived stigma. CONCLUSIONS: The diverse ways in which participants responded to screening, both psychologically and behaviourally, should direct a broader research agenda to ensure all stages of screening delivery and communication are designed to promote well-being, motivate positive behaviour change and maximize patient benefit

XO-5b: A Transiting Jupiter-sized Planet With A Four Day Period

The star XO-5 (GSC 02959-00729, V=12.1, G8V) hosts a Jupiter-sized, Rp=1.15+/-0.12 Rjup, transiting extrasolar planet, XO-5b, with an orbital period of P=4.187732+/-0.00002 days. The planet mass (Mp=1.15+/-0.08 Mjup) and surface gravity (gp=22+/-5 m/s^2) are significantly larger than expected by empirical Mp-P and Mp-P-[Fe/H] relationships. However, the deviation from the Mp-P relationship for XO-5b is not large enough to suggest a distinct type of planet as is suggested for GJ 436b, HAT-P-2b, and XO-3b. By coincidence XO-5 overlies the extreme H I plume that emanates from the interacting galaxy pair NGC 2444/NGC 2445 (Arp 143).Comment: 10 pages, 9 Figures, Submitted to Ap

Maximal entropy inference of oncogenicity from phosphorylation signaling

Point mutations in the phosphorylation domain of the Bcr-Abl fusion oncogene give rise to drug resistance in chronic myelogenous leukemia patients. These mutations alter kinase-mediated signaling function and phenotypic outcome. An information theoretic analysis of the correlation of phosphoproteomic profiling and transformation potency of the oncogene in different mutants is presented. The theory seeks to predict the leukemic transformation potency from the observed signaling by constructing a distribution of maximal entropy of site-specific phosphorylation events. The theory is developed with special reference to systems biology where high throughput measurements are typical. We seek sets of phosphorylation events most contributory to predicting the phenotype by determining the constraints on the signaling system. The relevance of a constraint is measured by how much it reduces the value of the entropy from its global maximum, where all events are equally likely. Application to experimental phospho-proteomics data for kinase inhibitor-resistant mutants shows that there is one dominant constraint and that other constraints are not relevant to a similar extent. This single constraint accounts for much of the correlation of phosphorylation events with the oncogenic potency and thereby usefully predicts the trends in the phenotypic output. An additional constraint possibly accounts for biological fine structure

A Transiting Planet of a Sun-like Star

A planet transits an 11th magnitude, G1V star in the constellation Corona Borealis. We designate the planet XO-1b, and the star, XO-1, also known as GSC 02041-01657. XO-1 lacks a trigonometric distance; we estimate it to be 200+-20 pc. Of the ten stars currently known to host extrasolar transiting planets, the star XO-1 is the most similar to the Sun in its physical characteristics: its radius is 1.0+-0.08 R_Sun, its mass is 1.0+-0.03 M_Sun, V sini < 3 km/s, and its metallicity [Fe/H] is 0.015+-0.04. The orbital period of the planet XO-1b is 3.941534+-0.000027 days, one of the longer ones known. The planetary mass is 0.90+-0.07 M_Jupiter, which is marginally larger than that of other transiting planets with periods between 3 and 4 days. Both the planetary radius and the inclination are functions of the spectroscopically determined stellar radius. If the stellar radius is 1.0+-0.08 R_Sun, then the planetary radius is 1.30+-0.11 R_Jupiter and the inclination of the orbit is 87.7+-1.2 degrees. We have demonstrated a productive international collaboration between professional and amateur astronomers that was important to distinguishing this planet from many other similar candidates.Comment: 31 pages, 9 figures, accepted for part 1 of Ap

Pulmonary nodules and CT screening: the past, present and future

Lung cancer screening has come a long way since the early studies with chest X-ray. Advancing technology and progress in the processing of images have enabled low dose CT to be tried and tested, and evidence suggests its use can result in a significant mortality benefit. There are several issues that need refining in order to successfully implement screening in the UK and elsewhere. Some countries have started patchy implementation of screening and there is increased recognition that the appropriate management of pulmonary nodules is crucial to optimise benefits of early detection, while reducing harm caused by inappropriate medical intervention. This review summarises and differentiates the many recent guidelines on pulmonary nodule management, discusses screening activity in other countries and exposes the present barriers to implementation in the UK

XO-2b: Transiting Hot Jupiter in a Metal-rich Common Proper Motion Binary

We report on a V=11.2 early K dwarf, XO-2 (GSC 03413-00005), that hosts a Rp=0.98+0.03/-0.01 Rjup, Mp=0.57+/-0.06 Mjup transiting extrasolar planet, XO-2b, with an orbital period of 2.615857+/-0.000005 days. XO-2 has high metallicity, [Fe/H]=0.45+/-0.02, high proper motion, mu_tot=157 mas/yr, and has a common proper motion stellar companion with 31" separation. The two stars are nearly identical twins, with very similar spectra and apparent magnitudes. Due to the high metallicity, these early K dwarf stars have a mass and radius close to solar, Ms=0.98+/-0.02 Msolar and Rs=0.97+0.02/-0.01 Rsolar. The high proper motion of XO-2 results from an eccentric orbit (Galactic pericenter, Rper<4 kpc) well confined to the Galactic disk (Zmax~100 pc). In addition, the phase space position of XO-2 is near the Hercules dynamical stream, which points to an origin of XO-2 in the metal-rich, inner Thin Disk and subsequent dynamical scattering into the solar neighborhood. We describe an efficient Markov Chain Monte Carlo algorithm for calculating the Bayesian posterior probability of the system parameters from a transit light curve.Comment: 14 pages, 10 Figures, Accepted in ApJ. Negligible changes to XO-2 system properties. Removed Chi^2 light curve analysis section, and simplified MCMC light curve analysis discussio