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Time-resolved carbamazepine crystallization from wet ethanol has been monitored using a combination of cryoTEM and 3D electron diffraction. Carbamazepine is shown to crystallize exclusively as a dihydrate after 180 s. When the timescale was reduced to 30 s, three further polymorphs could be identified. At 20 s, the development of early stage carbamazepine dihydrate was observed through phase separation. This work reveals two possible crystallization pathways present in this active pharmaceutical ingredient.

3D electron diffraction (3DED) has been used to follow polymorph evolution in the crystallization of glycine from aqueous solution. The three polymorphs of glycine which exist under ambient conditions follow the stability order β < α < γ. The least stable β polymorph forms within the first 3 min, but this begins to yield the α-form after only 1 min more. Both structures could be determined from continuous rotation electron diffraction data collected in less than 20 s on crystals of thickness ∼100 nm. Even though the γ-form is thermodynamically the most stable polymorph, kinetics favour the α-form, which dominates after prolonged standing. In the same sample, some β and one crystallite of the γ polymorph were also observed.

A massive galaxy cluster can serve as a magnifying glass for distant stellar populations, as strong gravitational lensing magnifies background galaxies and exposes details that are otherwise undetectable. In time-domain astronomy, imaging programmes with a short cadence are able to detect rapidly evolving transients, previously unseen by surveys designed for slowly evolving supernovae. Here, we describe two unusual transient events discovered in a Hubble Space Telescope programme that combined these techniques with high-cadence imaging on a field with a strong-lensing galaxy cluster. These transients were faster and fainter than any supernovae, but substantially more luminous than a classical nova. We find that they can be explained as separate eruptions of a luminous blue variable star or a recurrent nova, or as an unrelated pair of stellar microlensing events. To distinguish between these hypotheses will require clarification of the cluster lens models, along with more high-cadence imaging of the field that could detect related transient episodes. This discovery suggests that the intersection of strong lensing with high-cadence transient surveys may be a fruitful path for future astrophysical transient studies. Two unusual transient events, discovered by Hubble behind a strong-lensing galaxy cluster, can be explained as separate eruptions of a luminous blue variable star or a recurrent nova, or as an unrelated pair of stellar microlensing events.

Environmental flows are applied to regulated rivers, predominantly with the aim of benefiting native fauna. However, the outcomes for biodiversity and the mechanisms that underpin changes due to these manipulations are poorly understood. We examined the effects of elevated water release, of the magnitude used for riffle maintenance, on the movement and habitat use of the locally-threatened two-spined blackfish, Gadopsis bispinosus , in the Cotter River, a regulated upland stream in south-eastern Australia. We compared the behaviour of radio-tagged individuals during baseline flow conditions (0.12 m 3  s −1 ) and during elevated flow releases (1.74 m 3  s −1 ). Eight individuals (196 ± 8 mm TL) were radio-tracked at one site over 22 days, and six individuals (180 ± 5 mm TL) were monitored by fixed telemetry stations at a second site for 1 month. At both the sites, two-spined blackfish were nocturnal and occupied small linear ranges (23 ± 6 m). They preferentially used pools, but also used runs and riffles. Elevated discharge did not significantly affect movement, activity or dispersal of two-spined blackfish. Two individuals utilised inundated vegetation during high flow. Despite a small number of behavioural changes, there was no response to elevated flow at the population level. It is likely that the benthic nature of this species precludes its behaviour being affected by a 15-fold increase in-stream discharge. However, the indirect effects of flows of this magnitude on two-spined blackfish, and their responses to discharges of greater magnitude, remain to be investigated.

GALAXIES, mapped in two or three dimensions, are not distributed randomly but are clustered on small scales (<5 h −1 Mpc, where h ≈ 0.5–1 is Hubble's constant in units of 100 km s −1 Mpc −1 ), for reasons conventionally ascribed to the effects of gravity. Whether galaxies remain correlated on very large scales (∼ 50–100 h −1 Mpc) is of particular interest, because such structures are unexpected in most cosmological theories. We have combined data from four distinct surveys at the north and south Galactic poles to produce a well sampled distribution of galaxies by redshift on a linear scale extending to 2,000 h −1 Mpc. Here we report our finding of an excess correlation and an apparent regularity in the galaxy distribution with a characteristic scale of 128 h −1 Mpc. This structure is revealed only after the completion of recent surveys extending to redshift z > 0.2. Similarly deep surveys with greater angular spread are needed to verify our results and to determine the implications for cosmology.

RECENT observations of faint galaxies at near-infrared wavelengths 1–3 reveal a surprisingly low surface density when compared to the excess of blue galaxies seen at optical wavelengths 4 . Attempts to determine the cosmological curvature from the asymptotic surface density of faint galaxies thus produce conflicting results 3,5–7 . We propose to resolve this conflict with an evolutionary model in which galaxies merge at recent look-back times. The contrast between optical and infrared galaxy counts then follows from the very different lifetimes of stellar types contributing to emission in the galactic rest-frame. Together with evidence we present an increased star formation rate in galaxies at moderate redshift, the merging model can account for both the number–magnitude relations and available redshift distributions. A clear prediction is that there should be an absence of high-redshift galaxies in deep infrared-selected surveys. If correct, the model confirms earlier suspicions that galaxies cannot be used as reliable tracers of the geometry of the Universe.

The ALHAMBRA photometric system was specifically designed to perform a tomography of the Universe in some selected areas. Although mainly designed for extragalactic purposes, its 20 contiguous, equal-width, medium-band photometric system in the optical wavelength range, shows a great capacity for stellar classification. In this contribution we propose a methodology for stellar classification and physical parameter estimation (Teff, log g, [Fe/H], and color excess E(B – V)) based on 18 independent reddening-free Q-values from the ALHAMBRA photometry. Based on the theoretical Spectral library BaSeL 2.2, and applied to 288 stars from the Next Generation spectral Library (NGSL), we discuss the reliability of the method and its dependence on the extinction law used.

An emission line galaxy with the enormous far-IR luminosity of 3 x 10 to the 14th solar has been found at z = 2.286. The spectrum is very unusual, showing lines of high excitation but with very weak Lyman-alpha emission. A self-absorbed synchrotron model for the IR energy distribution cannot be ruled out, but a thermal origin seems more plausible. A radio-quiet quasar embedded in a very dusty galaxy could account for the IR emission, as might a starburst embedded in 1-10 billion solar masses of dust. The latter case demands so much dust that the object would probably be a massive galaxy in the process of formation. The presence of a large amount of dust in an object of such high redshift implies the generation of heavy elements at an early cosmological epoch.

The scale and patterns of movement and habitat use are primary considerations in the conservation and management of threatened species. Movement, activity and habitat use of the threatened two-spined blackfish Gadopsis bispinosus were assessed in a small upland reservoir in south-eastern Australia using manual and remote radio-telemetry. Movements and activity of two-spined blackfish ( n  = 19) were studied over a 28-day period and exhibited proportionately large directional crepuscular movement and activity with heightened activity continuing throughout the night (although movement was subdued). Two daily movement strategies were observed: movements from diurnal home-shelter habitats (predominantly rock) to macrophytes at night (14 individuals), and occupation of macrophytes during the entire diel period and restricted movement (five individuals). Daily movement strategies were fixed (not plastic) among all individuals, with one exception, for the duration of the study period. Rock, fallen timber and macrophytes were the most commonly used daytime shelter habitat (in order of preference). Although some information exists on movements and habitat use of this species and the congeneric river blackfish G. Marmoratus in lotic environments, we present the first study of movements and habitat use for either species in lentic environments. Given the occupation of lentic environments by this threatened species, the data presented in this study provide insight into the habitat requirements for this species, and offer opportunities for habitat enhancement in existing reservoirs within the species’ geographic range.

Observations of the large-scale structure of the universe suggest inhomogeneities on scales between 100h-1and 150h-1Mpc (where h ≈ 0.5-1 is the Hubble constant in units of 100 km·s-1·Mpc-1; 1 pc = 3.09 x 1016m). A deep redshift survey with a \"pencil-beam\" geometry of galaxies at the galactic poles indicated strong clustering, with a provocative regularity at 128h-1Mpc [Broadhurst, T. J., Ellis, R. S., Koo, D. C. \\& Szalay, A. S. (1990) Nature (London) 343, 726-728]. Using newly acquired data, we demonstrate how multiple deep probes overcome most of the statistical problems associated with single pencil beams. Our results from cross correlations of multiple pencil beams, containing over 1200 galaxies, indicate that the strong peak in the power spectrum results from structures of large transverse size, in agreement with our original conjecture. We also discuss the sensitivity of pencil-beam surveys to the topology of large-scale structures and compare them with sparsely sampled wide-angle local surveys.