Research capacity building in general practice: A new opportunity in Fremantle, WA

One of the great disappointments of primary care medicine has been the failure to develop a strong research tradition among general practitioners. This has happened despite the great legacy left by William Budd, James MacKenzie, and Will Pickles, and the clear acceptance that such research is necessary to improve patient care

Young Red Spheroidal Galaxies in the Hubble Deep Fields: Evidence for a Truncated IMF at ~2M_solar and a Constant Space Density to z~2

The optical-IR images of the Northern and Southern Hubble Deep Fields are used to measure the spectral and density evolution of early-type galaxies. The mean optical SED is found to evolve passively towards a mid F-star dominated spectrum by z ~ 2. We demonstrate with realistic simulations that hotter ellipticals would be readily visible if evolution progressed blueward and brightward at z > 2, following a standard IMF. The colour distributions are best fitted by a `red' IMF, deficient above ~2 M_solar and with a spread of formation in the range 1.5 < z_f < 2.5. Traditional age dating is spurious in this context, a distant elliptical can be young but appear red, with an apparent age >3 Gyrs independent of its formation redshift. Regarding density evolution, we demonstrate that the sharp decline in numbers claimed at z > 1 results from a selection bias against distant red galaxies in the optical, where the flux is too weak for morphological classification, but is remedied with relatively modest IR exposures revealing a roughly constant space density to z ~ 2. We point out that the lack of high mass star-formation inferred here and the requirement of metals implicates cooling-flows of pre-enriched gas in the creation of the stellar content of spheroidal galaxies. Deep-field X-ray images will be very helpful to examine this possibility.Comment: 6 pages, 3 figures, submitted to Astrophysical Journal Letters, typographical errors corrected, simulated images with different IMFs illustrated at http://astro.berkeley.edu/~bouwens/ellip.htm

Unrecognised Ebola virus infection in contact persons: what can we learn from it?

The epidemic of Ebola virus disease in west Africa in 2014–16 was the largest and most complex the world has ever seen. The four pillars of Ebola response include: case management, case finding and contact tracing, safe and dignified burial, and social mobilisation and community engagement. These four pillars are being implemented in the current outbreak in the Democratic Republic of the Congo (DRC), which is further complicated by its location in a conflict zone.1 Increased understanding of disease pathogenesis and the evaluation of novel therapeutics and vaccine candidates has informed current control measures, while access to survivors and their contacts in west Africa has also provided a unique opportunity to research filovirus transmission

The impact and response of mini-haloes and the interhalo medium on cosmic reionization

An ionization front (I-front) that propagates through an inhomogeneous medium is slowed down by self-shielding and recombination's. We perform cosmological radiation hydrodynamics simulations of the I-front propagation during the epoch of cosmic reionization. The simulations resolve gas in mini-haloes (halo mass 104 ≲ Mh[M⊙] ≲ 108) that could dominate recombination's, in a computational volume that is large enough to sample the abundance of such haloes. The numerical resolution is sufficient (gas-particle mass ∼20 M⊙ and spatial resolution <0.1 ckpc) to allow accurate modelling of the hydrodynamic response of gas to photoheating. We quantify the photoevaporation time of mini-haloes as a function of Mh and its dependence on the photoionization rate, Γ−12, and the redshift of reionization, zi. The recombination rate can be enhanced over that of a uniform medium by a factor ∼10−20 early on. The peak value increases with Γ−12 and decreases with zi, due to the enhanced contribution from mini-haloes. The clumping factor, cr, decreases to a factor of a few at ∼100 Myr after the passage of the I-front when the mini-haloes have been photoevaporated; this asymptotic value depends only weakly on Γ−12. Recombination's increase the required number of photons per baryon to reionize the Universe by 20 per cent–100 per cent, with the higher value occurring when Γ−12 is high and zi is low. We complement the numerical simulations with simple analytical models for the evaporation rate and the inverse Strömgren layer. The study also demonstrates the proficiency and potential of SPH-M1RT to address astrophysical problems in high-resolution cosmological simulations

All the colours of the rainbow.

Our perception of colour has always been a source of fascination, so it's little wonder that studies of the phenomenon date back hundreds of years. What, though, can modern scientists learn from medieval literature — and how do we go about it

Stereospecific Alkene Aziridination Using a Bifunctional Amino-Reagent:An Aza-Prilezhaev Reaction

In situ deprotection (TFA) of O-Ts activated N-Boc hydroxylamines triggers intramolecular aziridination of N-tethered alkenes to provide complex N-heterocyclic ring systems. Synthetic and computational studies corroborate a diastereospecific aza-Prilezhaev-type mechanism. The feasibility of related intermolecular alkene aziridinations is also demonstrated