Plasticity in transmission strategies of the malaria parasite, Plasmodium chabaudi : environmental and genetic effects

Parasites may alter their behaviour to cope with changes in the within-host environment. In particular, investment in transmission may alter in response to the availability of parasite resources or host immune responses. However, experimental and theoretical studies have drawn conflicting conclusions regarding parasites' optimal (adaptive) responses to deterioration in habitat quality. We analyse data from acute infections with six genotypes of the rodent malaria species to quantify how investment in transmission (gametocytes) is influenced by the within-host environment. Using a minimum of modelling assumptions, we find that proportional investment in gametocytogenesis increases sharply with host anaemia and also increases at low parasite densities. Further, stronger dependence of investment on parasite density is associated with greater virulence of the parasite genotype. Our study provides a robust quantitative framework for studying parasites' responses to the host environment and whether these responses are adaptive, which is crucial for predicting the short-term and evolutionary impact of transmission-blocking treatments for parasitic diseases

Healthier central England or North-South divide? Analysis of national survey data on smoking and high-risk drinking.

OBJECTIVES: This paper compares patterns of smoking and high-risk alcohol use across regions in England, and assesses the impact on these of adjusting for sociodemographic characteristics. DESIGN: Population survey of 53 922 adults in England aged 16+ taking part in the Alcohol and Smoking Toolkit Studies. MEASURES: Participants answered questions regarding their socioeconomic status (SES), gender, age, ethnicity, Government Office Region, smoking status and completed the Alcohol Use Disorders Identification Test (AUDIT). High-risk drinkers were defined as those with a score of 8 or more (7 or more for women) on the AUDIT. RESULTS: In unadjusted analyses, relative to the South West, those in the North of England were more likely to smoke, while those from the East of England, South East and London were less likely. After adjustment for sociodemographics, smoking prevalence was no higher in North East (RR 0.97, p>0.05), North West (RR 0.98, p>0.05) or Yorkshire and the Humber (RR 1.03, p>0.05) but was less common in the East and West Midlands (RR 0.86, p0.05) CONCLUSIONS: In adjusted analyses, smoking and high-risk drinking appear less common in 'central England' than in the rest of the country. Regional differences in smoking, but not those in high-risk drinking, appear to be explained to some extent by sociodemographic disparities

Monitoring young associations and open clusters with Kepler in two-wheel mode

We outline a proposal to use the Kepler spacecraft in two-wheel mode to monitor a handful of young associations and open clusters, for a few weeks each. Judging from the experience of similar projects using ground-based telescopes and the CoRoT spacecraft, this program would transform our understanding of early stellar evolution through the study of pulsations, rotation, activity, the detection and characterisation of eclipsing binaries, and the possible detection of transiting exoplanets. Importantly, Kepler's wide field-of-view would enable key spatially extended, nearby regions to be monitored in their entirety for the first time, and the proposed observations would exploit unique synergies with the GAIA ESO spectroscopic survey and, in the longer term, the GAIA mission itself. We also outline possible strategies for optimising the photometric performance of Kepler in two-wheel mode by modelling pixel sensitivity variations and other systematics.Comment: 10 pages, 6 figures, white paper submitted in response to NASA call for community input for alternative science investigations for the Kepler spacecraf

Incidence and risk factors of institutionalisation in Parkinson's disease and atypical parkinsonism

Open Access via the Elsevier Agreement We would like to thank the patients for their participation and the research staff who collected data and supported the study database. The PINE study was funded by Parkinson's UK (grant numbers G0502, G0914, and G1302), the Scottish Chief Scientist Office (CAF/12/05, PCL/17/10), NHS Grampian endowments, the BMA Doris Hillier award, RS Macdonald Trust, the BUPA Foundation and SPRING. Yan Li is funded by a studentship from the Meikle Foundation.Peer reviewedPublisher PD

Can MONDian vector theories explain the cosmic speed up ?

Generalized Einstein - Aether vector field models have been shown to provide, in the weak field regime, modifications to gravity which can be reconciled with the successfull MOND proposal. Very little is known, however, on the function F(K) defining the vector field Lagrangian so that an analysis of the viability of such theories at the cosmological scales has never been performed. As a first step along this route, we rely on the relation between F(K) and the MOND interpolating function $\mu(a/a_0)$ to assign the vector field Lagrangian thus obtaining what we refer to as "MONDian vector models". Since they are able by construction to recover the MOND successes on galaxy scales, we investigate whether they can also drive the observed accelerated expansion by fitting the models to the Type Ia Supernovae data. Should be this the case, we have a unified framework where both dark energy and dark matter can be seen as different manifestations of a single vector field. It turns out that both MONDian vector models are able to well fit the low redshift data on Type Ia Supernovae, while some tension could be present in the high z regime.Comment: 15 pages, 5 tables, 4 figures, accepted for publication on Physical Review

Milky Way Mass Models and MOND

Using the Tuorla-Heidelberg model for the mass distribution of the Milky Way, I determine the rotation curve predicted by MOND. The result is in good agreement with the observed terminal velocities interior to the solar radius and with estimates of the Galaxy's rotation curve exterior thereto. There are no fit parameters: given the mass distribution, MOND provides a good match to the rotation curve. The Tuorla-Heidelberg model does allow for a variety of exponential scale lengths; MOND prefers short scale lengths in the range 2.0 to 2.5 kpc. The favored value of scale length depends somewhat on the choice of interpolation function. There is some preference for the `simple' interpolation function as found by Famaey & Binney. I introduce an interpolation function that shares the advantages of the simple function on galaxy scales while having a much smaller impact in the solar system. I also solve the inverse problem, inferring the surface mass density distribution of the Milky Way from the terminal velocities. The result is a Galaxy with `bumps and wiggles' in both its luminosity profile and rotation curve that are reminiscent of those frequently observed in external galaxies.Comment: Accepted for publication in the Astrophysical Journal. 31 pages including 8 figures and 3 table

Hunters and gatherers: Strategies for curriculum mapping and data collection for assuring learning

Assurance of learning is a predominant feature in both quality enhancement and assurance in higher education. It involves making program expectations and standards explicit, then systematically gathering, and interpreting evidence to determine how well performance matches those expectations. This benefits the institution, ensuring program aims are evaluated and used for program development, and is important for external scrutiny (AUQA, TEQSA, professional bodies). This project aims to investigate two elements of assurance of learning: (1) mapping graduate attributes throughout a program; and (2) collecting assurance data. It will conduct an audit across disciplines subject to accreditation in Australian universities to evaluate current methods of mapping graduate attributes and their impact on the curriculum, and also the systems used to collect and store data. This information will be critically analysed to develop strategy on curriculum mapping and data collection. It will draw upon the use of existing software packages (e.g., SOS - mapping; ReView, SPARKPLUS collection) to support the efficient and effective implementation strategies

The JCMT Nearby Galaxies Legacy Survey – XI. Environmental Variations in the Atomic and Molecular Gas Radial Profiles of Nearby Galaxies

We present an analysis of the radial profiles of a sample of 43 H I-flux selected spiral galaxies from the Nearby Galaxies Legacy Survey (NGLS) with resolved James Clerk Maxwell Telescope (JCMT) CO J = 3 − 2 and/or Very Large Array (VLA) H I maps. Comparing the Virgo and non-Virgo populations, we confirm that the H i discs are truncated in the Virgo sample, even for these relatively H i-rich galaxies. On the other hand, the H2 distribution is enhanced for the Virgo galaxies near their centres, resulting in higher H2 to H I ratios and steeper H2 and total gas radial profiles. This is likely due to the effects of moderate ram pressure stripping in the cluster environment, which would preferentially remove low-density gas in the outskirts while enhancing higher density gas near the centre. Combined with Hα star formation rate data, we find that the star formation efficiency (SFR/H2) is relatively constant with radius for both samples, but the Virgo galaxies have an ∼40 per cent lower star formation efficiency than the non-Virgo galaxies

The JCMT Nearby Galaxies Legacy Survey -- XI. -- Environmental Variations in the Atomic and Molecular Gas Radial Profiles of Nearby Spiral Galaxies

This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society. ©: 2017 The Author (s). Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.We present an analysis of the radial profiles of a sample of 43 HI-flux selected spiral galaxies from the Nearby Galaxies Legacy Survey (NGLS) with resolved James Clerk Maxwell Telescope (JCMT) CO $J=3-2$ and/or Very Large Array (VLA) HI maps. Comparing the Virgo and non-Virgo populations, we confirm that the HI disks are truncated in the Virgo sample, even for these relatively HI-rich galaxies. On the other hand, the H$_{2}$ distribution is enhanced for Virgo galaxies near their centres, resulting in higher H$_{2}$ to HI ratios and steeper H$_{2}$ and total gas radial profiles. This is likely due to the effects of moderate ram pressure stripping in the cluster environment, which would preferentially remove low density gas in the outskirts while enhancing higher density gas near the centre. Combined with H$\alpha$ star formation rate data, we find that the star formation efficiency (SFR/H$_{2}$) is relatively constant with radius for both samples, but Virgo galaxies have a $\sim40\%$ lower star formation efficiency than non-Virgo galaxies.Peer reviewedFinal Published versio