We present the first geochemical data of archaeological obsidian for Isla Victoria, Nahuel Huapi National Park in Patagonia. XRF analyses were performed on 15 samples of obsidian-like rocks from the Puerto Tranquilo 1 site. Only five of the artifacts—all of which come from upper levels of the site—correspond to obsidian as a raw material. The provenance analysis indicates the use of obsidian sources located in the Andean Forest area of southern Neuquen Province. Based on these preliminary results, we propose a north–south circulation axis for this raw material. These geographic results are discussed in relation to the information available regionally.

In November 2009, we initiated a multistate investigation of Salmonella Montevideo infections with pulsed-field gel electrophoresis pattern JIXX01.0011. We identified 272 cases in 44 states with illness onset dates ranging from 1 July 2009 to 14 April 2010. To help generate hypotheses, warehouse store membership card information was collected to identify products consumed by cases. These records identified 19 ill persons who purchased company A salami products before onset of illness. A case-control study was conducted. Ready-to-eat salami consumption was significantly associated with illness (matched odds ratio 8·5, 95% confidence interval 2·1–75·9). The outbreak strain was isolated from company A salami products from an environmental sample from one manufacturing plant, and sealed containers of black and red pepper at the facility. This outbreak illustrates the importance of using membership card information to assist in identifying suspect vehicles, the potential for spices to contaminate ready-to-eat products, and preventing raw ingredient contamination of these products.

Solid-stemmed varieties of common wheat are more resistant than hollowstemmed varieties to the wheat stem sawfly, Cephus cinctus Nort. If closely related lines of wheat with a considerable range of sawfly-resistance and stem solidness were available, entomologists could use them to analyse some of the mechanisms of resistance.

The hypothesis that schizophrenia is caused by the release of prostaglandin E into the hypothalamus and may sometimes be accompanied by an elevation of temperature was examined by a clinical trial of the prostaglandin E suppressant N-acetyl-p-amino-phenol (paracetamol, acetaminophen). Ten acute schizophrenic patients were included in a double-blind, crossover trial of paracetamol and a placebo, in which each treatment was given for a week. Regular 4-hourly temperatures were recorded in all these cases and in 5 non-schizophrenic patients for comparison. The findings provided no evidence that paracetamol mitigated the symptoms of schizophrenia. The temperatures of the schizophrenics were not elevated more than those of the controls, but the number of cases used was probably too small for this finding to be conclusive.

Extended abstract of a paper presented at Microscopy and Microanalysis 2009 in Richmond, Virginia, USA, July 26 – July 30, 2009

The Mesozoic forearc of Alexander Island, Antarctica, is one of the few places in the world where the original stratigraphic relationship between a forearc basin and an accretionary complex is exposed. Newlydiscovered sedimentary rocks exposed at the western edge of the forearc basin fill (the Kimmeridgian–Albian Fossil Bluff Group) record the events associated with the basin formation. These strata are assigned to the newly defined Selene Nunatak Formation (?Bathonian) and Atoll Nunataks Formation (?Bathonian-Tithonian) within the Fossil Bluff Group.

The Selene Nunatak Formation contains variable thicknesses of conglomeratesand sandstones, predominantly derived from the LeMay Group accretionary complex upon which it is unconformable. The formation marks emergence and subsequent erosion of the inner forearc area. It is conformably overlain by the1 km thick Atoll Nunataks Formation, characterized by thinly-bedded mudstones and silty mudstones representing a marine transgression followed by trench-slope deposition. The Atoll Nunataks Formation marks a phase of subsidence, possibly in response to tectonic events in the accretionary prism that are known to have occurred at about the same time.

The Atoll Nunataks Formation is conformably overlain by the Himalia Ridge Formation, a thick sequence of basin-wide arc-derived conglomerates. This transition from fine- to coarse-grained deposition suggests that a well-developed depositional trough (and hence trench-slope break) had formed by that time. The Atoll Nunataks Formation therefore spans the formation of the forearc basin, and marks the transition from trench-slope to forearc basin deposition.

Is it possible for a finite p-group to have only one conjugacy class of maximal size? This question was opened to public consideration in a paper [2] of John Meldrum dealing with the breadth of the wreath product of finite p-groups. His Theorem 21 gives a formula for the breadth of A wr B in terms of various constants including the breadths of A and B, a formula which differs according to whether or not A has a unique largest class. Hence the question.

In (2) a finite p-group G is said to be nearly regular if it has the following two properties:

(i) There exists a central subgroup Z of order p and G/Z is regular.

(ii) If x ∈ G and y ∈ γ2(G), then gp{x, y} is regular.

Let

and

be, respectively, the upper and lower central series of a group G. Our purpose in this note is to extend known results and find some information as to which of the factors Zk/Zk−1 and Γk/Γk+1 may be infinite. Though our conclusions about the lower central series will be quite general we assume in the other case that the group is f.n., i.e. an extension of a finite group by a nilpotent group. The essential facts about f.n. groups are to be found in P. Hall's paper (4). We also refer to (4) for general notation; we reserve the letter k for positive integers.

We investigated the effects of crop type on numbers and movements of wood mice Apodemus sylvaticus in field edges and in arable fields containing either winter wheat, winter barley or oil-seed rape, grown on a 3-year rotation. We also investigated the effect of habitat (field centre vs edge), and of season and year. This was done at the individual level using radio-tracking, and at the population level using live-trapping. Wood mouse population size (estimated as minimum number alive) was significantly affected by season. Wood mouse numbers also differed between crop types. Rape field centres and edges had significantly lower numbers than did barley or wheat field centres and edges. Populations were largest from April to July, when the crop was tall. In winter, significantly more mice were found in field edges compared with field centres. The patterns of movement of individual mice also showed differences between habitats and between seasons. Mice were found to move more quickly when they were tracked through rape compared with the other crops. When the crop was growing, they moved faster through field edges bordered with hedgerow than they did through wood. This pattern was reversed later in the year when the crop was tall. The distances moved during a session of tracking showed differences which paralleled those for speed of movement. Also, males tended to move faster than females. Differences between the sexes in movement patterns were affected by season; when the crop was down (in winter) females moved further than males during a session of tracking, but when the crop was growing and tall, this was reversed.

Forty-eight wood mice Apodemus sylvaticus were radio-tracked over an estimated 1500 h yielding 9000 fixes. The mice were living in three contiguous arable fields, and showed that they respond to weedy microhabitat patches within superficially homogeneous crops. Plant species' abundance and the composition of the seed bank were assessed in quadrats taken in areas in which (a) mice foraged, (b) through which mice travelled, or (c) at random within each home range. Wood mice avoided foraging in areas with a high abundance of bare earth, and selected areas with a high abundance of Alopecurus myosuroides, Stellaria media, Avena fatua, Galium aparine or Bromus sterilis. The food plants apparently selected by wood mice differed markedly between months and between sexes. This may relate to the energetic and nutritional demands incurred by the contrasting reproductive tactics of male and female wood mice. There were no differences between seed bank samples taken from quadrats where the mice foraged, travelled through, or which were selected at random. Our study, the first large-scale analysis of wood mouse microhabitat preference using radio-tracking, reveals that whereas the mice do not react to heterogeneity on the scale of the mosaic of crop fields, they are greatly influenced by the dispersion of food plants within the superficially homogeneous crop itself.

Wood mice Apodemus sylvaticus were radio-tracked in an area covering three cereal fields, which was notionally divided into 5×5 m squares; each of these squares was classified to one of four habitat types (hedgerow, wheat, barley and oil-seed rape). From a sample of 79 radio-tracked wood mice, yielding 8500 fixes, we defined home-range boundaries and estimated for two seasons: (a) the extent to which each habitat was present in each individual's home range relative to its overall availability in the surrounding landscape; (b) the extent to which each habitat was used by the mice relative to its abundance within a home range. Hedgerow ranked highest in preference (as distinct from use) for all comparisons made in both winter and summer. In winter, home ranges contained significantly more hedgerow than barley and wheat, and significantly more rape than wheat. Animals also used the habitats within their home ranges non-randomly, with a significant preference for hedgerow. In summer, home ranges contained significantly less rape than other habitats. Habitats within home ranges were used at random. Seasonal patterns in habitat use appeared to be largely a response to seasonal disturbance and the availability of cover in the fields.

The northern, James Ross Island region of the Larsen Basin, on the eastern, back-arc margin of the Antarctic Peninsula magmatic arc, includes one of the thickest and most complete Upper Cretaceous sedimentary successions exposed in the Southern Hemisphere. However, the southern part of the basin remains poorly known, mainly owing to inaccessibility and lack of exposure. Table Nunatak, an isolated, 1-km-long, 400-m-wide outcrop at the tip of Kenyon Peninsula, is the only known exposure of Upper Cretaceous or younger strata in this region. The 62-m-thick succession exposed there is assigned to the newly defined Table Nunatak Formation. It consists mainly of sharp-based, amalgamated beds of fine-grained sandstone up to 2.8 m thick, with subordinate intervals of intensely bioturbated mudstone. Wave ripples are present at some levels, and locally developed swaley cross-stratification provides evidence for storm-generated combined-flow deposition. However, most sandstone beds appear to be internally structureless apart from normal grading, and are interpreted as the direct suspension deposits of highly sediment-charged storm- and/or flood-related flows. The succession represents relatively nearshore deposition, probably at the mouth of a river or deltaic distributary channel. Charcoalified plant debris, abundant at the tops of some sandstone beds, suggests a periodically wildfire-swept hinterland forested largely by coniferous trees. Dinoflagellate cyst assemblages indicate a late Santonian age, and suggest correlation with the basal part of the Lachman Crags Member of the Santa Marta Formation (Marambio Group) on James Ross Island. Palaeocurrents, sandstone petrography and the high sediment supply rate proposed for the Table Nunatak Formation, suggest a relatively high-relief source area to the west, with large-scale erosion of granitoid plutons and metamorphic rocks, possibly related to arc uplift during a mid-Cretaceous compressional episode. The formation is evidence of a major southward extension of the Upper Cretaceous strata exposed in the northern Larsen Basin, and suggests lateral continuity of shallow-marine deposition for at least 500–600 km along the Weddell Sea margin of the Antarctic Peninsula in Santonian times.