Subglacial Antarctic aquatic environments are important targets for scientific exploration due to the unique ecosystems they support and their sediments containing palaeoenvironmental records. Directly accessing these environments while preventing forward contamination and demonstrating that it has not been introduced is logistically challenging. The Whillans Ice Stream Subglacial Access Research Drilling (WISSARD) project designed, tested and implemented a microbiologically and chemically clean method of hot-water drilling that was subsequently used to access subglacial aquatic environments. We report microbiological and biogeochemical data collected from the drilling system and underlying water columns during sub-ice explorations beneath the McMurdo and Ross ice shelves and Whillans Ice Stream. Our method reduced microbial concentrations in the drill water to values three orders of magnitude lower than those observed in Whillans Subglacial Lake. Furthermore, the water chemistry and composition of microorganisms in the drill water were distinct from those in the subglacial water cavities. The submicron filtration and ultraviolet irradiation of the water provided drilling conditions that satisfied environmental recommendations made for such activities by national and international committees. Our approach to minimizing forward chemical and microbiological contamination serves as a prototype for future efforts to access subglacial aquatic environments beneath glaciers and ice sheets.

Measurements made at John Evans Glacier, eastern Ellesmere Island, Nunavut, Canada in 1994 and 1996 provide new insight into the internal hydrology of polythermal glaciers. During the early part of each melt season, supraglacial waters enter the glacier via a crevasse field about 4 km from the terminus and are stored in a subglacial reservoir. Release of the water from the reservoir occurs initially via an artesian fountain on the glacier surface and by upwelling of waters through subglacial sediments at the terminus (event1). Channelization of the subglacial waters then occurs and water is discharged as an outburst flood (event 2), which releases a considerably larger volume of water than event 1. Thus, drainage of the subglacial reservoir follows a cyclical pattern in which discharge oscillations increase in amplitude over time. The cycle may end with complete reservoir drainage. The total volume of water released was much greater in 1994 than in 1996, primarily because the 1994 melt season was longer and warmer than the 1996 season. Interannual differences in the form of the outflow hydrographs, and in the extent and timing of connections between the subglacial reservoir and marginal melt streams, are linked to variations in the size and rate of growth of the subglacial reservoir. This hydrological behaviour may have important implications for the dynamics of polythermal glaciers.

The Whillans Ice Stream Subglacial Access Research Drilling (WISSARD) project will test the overarching hypothesis that an active hydrological system exists beneath a West Antarctic ice stream that exerts a major control on ice dynamics, and the metabolic and phylogenetic diversity of the microbial community in subglacial water and sediment. WISSARD will explore Subglacial Lake Whillans (SLW, unofficial name) and its outflow toward the grounding line where it is thought to enter the Ross Ice Shelf seawater cavity. Introducing microbial contamination to the subglacial environment during drilling operations could compromise environmental stewardship and the science objectives of the project, consequently we developed a set of tools and procedures to directly address these issues. WISSARD hot water drilling efforts will include a custom water treatment system designed to remove micron and sub-micron sized particles (biotic and abiotic), irradiate the drilling water with germicidal ultraviolet (UV) radiation, and pasteurize the water to reduce the viability of persisting microbial contamination. Our clean access protocols also include methods to reduce microbial contamination on the surfaces of cables/hoses and down-borehole equipment using germicidal UV exposure and chemical disinfection. This paper presents experimental data showing that our protocols will meet expectations established by international agreement between participating Antarctic nations.

To examine the contribution of genetic factors to food choice, we determined dietary patterns from food frequency questionnaires in 3262 UK female twins aged 18 to 79 years. Five distinct dietary patterns were identified (fruit and vegetable, high alcohol, traditional English, dieting, low meat) that accounted for 22% of the total variance. These patterns are similar to those found in other singleton Western populations, and were related to body mass index, smoking status, physical activity and deprivation scores. Older subjects had higher scores on the fruit and vegetable and traditional English patterns, while lower social deprivation was associated with higher scores for fruit and vegetable, and lower scores for traditional English patterns. All 5 patterns were heritable, with estimates ranging from 41% to 48%. Among individual dietary components, a strongly heritable component was identified for garlic (46%), coffee (41%), fruit and vegetable sources (49%), and red meat (39%). Our results indicate that genetic factors have an important influence in determining food choice and dietary habits in Western populations. The relatively high heritability of specific dietary components implicates taste perception as a possible target for future genetic studies.

Properties of radiatively cooled supersonic plasma jets formed by ablation of thin Al foils driven by 1.4 MA, 250 ns current pulse are presented. The jets are highly collimated with half-opening angles of ~2°. Measurements of the flow velocity (~60 km/s) and plasma temperature (~15 eV) in the jet with Thomson scattering diagnostic give internal Mach number of M ~ 3, suggesting additional collimation of the jet by toroidal magnetic fields.

The formation of supersonic, radiatively cooled plasma jets with applications to laboratory astrophysics has been an active area of research on the MAGPIE generator. One of the ways of producing astrophysically-relevant jets in the laboratory is by using the ablation of plasma from a radial foil Z-pinch. In this configuration a ~1.4 MA, 250 ns current pulse is introduced into an aluminium disk with a thickness of 15 μm. The ablated plasma from the foil converges on the axis, producing a steady and collimated jet with a typical axial velocity of ~100 km/s. The setup allows for the addition of argon above the foil for jet-ambient interaction studies. The interaction is characterised by the formation of several shock features, which are presented and discussed from experimental data and numerical simulations.

An outbreak of suspected infectious hepatitis in a primary school was investigated using sensitive diagnostic methods for hepatitis A. A total of 116 sera from children were tested for the presence of both IgM and IgG antibodies to hepatitis A (HAV). The results were compared to those obtained for samples from a control school. IgG antibodies were present in 45 % and 10% of the children in the outbreak and control schools respectively.

The sera of 3522 women who attended an antenatal clinic in Birmingham. England were tested anonymously for antibodies against HTLV-1. Samples from 5 women (0·14%) were positive, one serum showed indeterminate reactivity. Two of the women (0·06%) were born in the West Indies (of Afro-Caribbean ethnic origin), one (0·03%) in Africa (of African ethnic origin), and three (0·09%) were white Caucasian women born in the UK. Thus, HTLV-1 infection in pregnant women in the UK, though comparatively rare, is not negligible. As transmission of HTLV-1 to the newborn via breast milk has been observed and as seropositive mothers can be advised to refrain from breastfeeding or to treat their milk, the question of routine screening for HTLV-1 infection during antenatal care is discussed.

The long-term physiological effects of refined carbohydrates on appetite and mood remain unclear. Reported effects when subjects are not blind may be due to expectations and have rarely been studied for more than 24 h. The present study compared the effects of supplementary soft drinks added to the diet over 4 weeks on dietary intake, mood and BMI in normal-weight women (n 133). Subjects were categorised as ‘watchers’ or ‘non-watchers’ of what they ate then received sucrose or artificially sweetened drinks (4 × 250 ml per d). Expectancies were varied by labelling drinks ‘sugar’ or ‘diet’ in a counter-balanced design. Sucrose supplements provided 1800 kJ per d and sweetener supplements provided 67 kJ per d. Food intake was measured with a 7 d diary and mood with ten single Likert scales. By 4 weeks, sucrose supplements significantly reduced total carbohydrate intake (F(1,129) = 53·81; P < 0·001), fat (F(2,250) = 33·33; P < 0·001) and protein intake (F(2,250) = 28·04; P < 0·001) compared with sweetener supplements. Mean daily energy intake increased by just under 1000 kJ compared with baseline (t (67 df) = 3·82; P < 0·001) and was associated with a non-significant trend for those receiving sucrose to gain weight. There were no effects on appetite or mood. Neither dietary restraint status as measured by the Dutch Eating Behaviour Questionnaire nor the expectancy procedure had effects. Expectancies influenced mood only during baseline week. It is concluded that sucrose satiates, rather than stimulates, appetite or negative mood in normal-weight subjects.

Extended abstract of a paper presented at Microscopy and Microanalysis 2006 in Chicago, Illinois, USA, July 30 – August 3, 2005

The Norse colonisation or landnám of the North Atlantic islands of the Faroes, Iceland, and Greenland from the ninth century AD onwards provides opportunities to examine human environmental impacts on ‘pristine’ landscapes on an environmental gradient from warmer, more maritime conditions in the east to colder, more continental conditions in the west. This paper considers key environmental contrasts across the Atlantic and initial settlement impacts on the biota and landscape. Before landnám, the modes of origin of the biota (which resulted in boreo-temperate affinities), a lack of endemic species, limited diversity, and no grazing mammals on the Faroes or Iceland, were crucial in determining environmental sensitivity to human impact and, in particular, the impact of introduced domestic animals. Gathering new data and understanding their geographical patterns and changes through time are seen as crucial when tackling fundamental questions about human interactions with the environment, which are relevant to both understanding the past and planning for the future.

We present fast (72ms) spectroscopy of AM Her obtained at an intermediate brightness state just before a rise to a high state. Interesting features in the line behaviour of AM Her are noted and the variability spectrum is presented and compared to that of SS Cyg.

We review our understanding of the prototype “Propeller” system AE Aqr and we examine its flaring behaviour in detail. The flares are thought to arise from collisions between high density regions in the material expelled from the system after interaction with the rapidly rotating magnetosphere of the white dwarf. We show calculations of the time-dependent emergent optical spectra from the resulting hot, expanding ball of gas and derive values for the mass, lengthscale and temperature of the material involved. We see that the fits suggest that the secondary star in this system has reduced metal abundances and that, counter-intuitively, the evolution of the fireballs is best modelled as isothermal.

Greenland, far north land of the Atlantic, has often been beyond the limit of European farming settlement. One of its Norse settlements, colonized just before AD 1000, is — astonishingly — not even at the southern tip, but a way up the west coast, the ‘Western Settlement’. Environmental studies show why its occupation came to an end within five centuries, leaving Greenland once more a place of Arctic-adapted hunters.

Genetic and technological studies have revealed correlations between different individual, or combinations of, alleles of milk proteins and parameters such as cheese yield, the compositional characteristics of milk and total lactation yield. The kappa casein B allele is better for cheese-making, for example (Table 1): the mutation may alter the mechanism by which this protein stabilises the micelles of the caldum-sensitive caseins against precipitation. When rennin cleaves kappa casein between amino acids 105 and 106 the micelle is destabilised and clotting of milk into curds ensues. Therefore, selection for defined alleles or haplotypes could be desirable.

Until now selection for milk protein alleles was only possible by the analysis of the proteins in milk. For sire selection this required analysis of milk from daughters which is time consuming and expensive. However, phenotypic variation in the proteins arises from base substitutions in the DNA, as is illustrated in Figure 1 for the kappa casein gene.