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We present the first high-resolution (sub-annual) dust particle data set from West Antarctica, developed from the West Antarctic Ice Sheet (WAIS) Divide deep ice core (79.468° S, 112.086° W), and use it to reconstruct changes in atmospheric circulation over the past 2400 years. We find a background dust flux of ~4 mg m−2 year−1 and a mode particle size of 5–8 μm diameter. Through comparing the WAIS Divide record with other Antarctic ice core particle records, we observe that coastal and lower-elevation sites have higher dust fluxes and coarser particle size distributions (PSDs) than sites on the East Antarctic plateau, suggesting input from local dust sources at these lower-elevation sites. In order to explore the use of the WAIS Divide dust PSD as a proxy for past atmospheric circulation, we make quantitative comparisons between both mid-latitude zonal wind speed and West Antarctic meridional wind speed and the dust size record, finding significant positive interannual relationships. We find that the dust PSD is related to mid-latitude zonal wind speed via cyclonic activity in the Amundsen Sea region. Using our PSD record, and through comparison with spatially distributed climate reconstructions from the Southern Hemisphere (SH) middle and high latitudes, we infer that the SH westerlies occupied a more southerly position from circa 1050 to 1400 CE (Common Era), coinciding with the Medieval Climate Anomaly (MCA). Subsequently, at ca. 1430 CE, the wind belt shifted equatorward, where it remained until the mid-to-late twentieth century. We find covariability between reconstructions of El Niño–Southern Oscillation (ENSO) and the mid-latitude westerly winds in the eastern Pacific, suggesting that centennial-scale circulation changes in this region are strongly influenced by the tropical Pacific. Further, we observe increased coarse particle deposition over the past 50 years, consistent with observations that the SH westerlies have been shifting southward and intensifying in recent decades.

Dimethyl sulfide (DMS) is primarily emitted by marine phytoplankton and oxidized in the atmosphere to form methanesulfonic acid (MSA) and sulfate aerosols. Ice cores in regions affected by anthropogenic pollution show an industrial-era decline in MSA, which has previously been interpreted as indicating a decline in phytoplankton abundance. However, a simultaneous increase in DMS-derived sulfate (bioSO4) in a Greenland ice core suggests that pollution-driven oxidant changes caused the decline in MSA by influencing the relative production of MSA versus bioSO4. Here we use GEOS-Chem, a global chemical transport model, and a zero-dimensional box model over three time periods (preindustrial era, peak North Atlantic NOx pollution, and 21st century) to investigate the chemical drivers of industrial-era changes in MSA and bioSO4, and we examine whether four DMS oxidation mechanisms reproduce trends and seasonality in observations. We find that box model and GEOS-Chem simulations can only partially reproduce ice core trends in MSA and bioSO4 and that wide variation in model results reflects sensitivity to DMS oxidation mechanism and oxidant concentrations. Our simulations support the hypothesized increase in DMS oxidation by the nitrate radical over the industrial era, which increases bioSO4 production, but competing factors such as oxidation by BrO result in increased MSA production in some simulations, which is inconsistent with observations. To improve understanding of DMS oxidation, future work should investigate aqueous-phase chemistry, which produces 82 %–99 % of MSA and bioSO4 in our simulations, and constrain atmospheric oxidant concentrations, including the nitrate radical, hydroxyl radical, and reactive halogens.

Within ice core science, woman-led studies contain 20% more women co-authors than man-led studies, and exceed the estimated proportion of women within the community by nearly 10%. We conclude that collaboration with other women is a key factor in closing gender gaps in science.Authorship statistics from ice core science suggest that collaboration between women is a key factor in closing gender gaps in scientific publishing.

A new ice core from West Antarctica shows that, during the last ice age, abrupt Northern Hemisphere climate variations were followed two centuries later by a response in Antarctica, suggesting an oceanic propagation of the climate signal to the Southern Hemisphere high latitudes. Climate seesaw swings north to south The bipolar seesaw theory explains certain abrupt episodes of climate change as a consequence of an interhemispheric redistribution of heat; when one polar region is warming, the other cools. So far, it has been unclear if the Northern Hemisphere is forcing the Southern Hemisphere or vice versa, and whether the seesaw operates via oceanic or atmospheric mechanisms. This study, synthesizing data from several climate laboratories, uses high-resolution data from the recently drilled WAIS Divide Antarctic ice core, combined with data from Greenland, to show that during much of the past 65,000 years, the north has led the south for both cooling and warming events. Abrupt Northern Hemisphere climate variations were followed two centuries later by a response in Antarctica, suggesting an oceanic propagation of the climate signal to the Southern Hemisphere high latitudes. The last glacial period exhibited abrupt Dansgaard–Oeschger climatic oscillations, evidence of which is preserved in a variety of Northern Hemisphere palaeoclimate archives 1 . Ice cores show that Antarctica cooled during the warm phases of the Greenland Dansgaard–Oeschger cycle and vice versa 2 , 3 , suggesting an interhemispheric redistribution of heat through a mechanism called the bipolar seesaw 4 , 5 , 6 . Variations in the Atlantic meridional overturning circulation (AMOC) strength are thought to have been important, but much uncertainty remains regarding the dynamics and trigger of these abrupt events 7 , 8 , 9 . Key information is contained in the relative phasing of hemispheric climate variations, yet the large, poorly constrained difference between gas age and ice age and the relatively low resolution of methane records from Antarctic ice cores have so far precluded methane-based synchronization at the required sub-centennial precision 2 , 3 , 10 . Here we use a recently drilled high-accumulation Antarctic ice core to show that, on average, abrupt Greenland warming leads the corresponding Antarctic cooling onset by 218 ± 92 years (2 σ ) for Dansgaard–Oeschger events, including the Bølling event; Greenland cooling leads the corresponding onset of Antarctic warming by 208 ± 96 years. Our results demonstrate a north-to-south directionality of the abrupt climatic signal, which is propagated to the Southern Hemisphere high latitudes by oceanic rather than atmospheric processes. The similar interpolar phasing of warming and cooling transitions suggests that the transfer time of the climatic signal is independent of the AMOC background state. Our findings confirm a central role for ocean circulation in the bipolar seesaw and provide clear criteria for assessing hypotheses and model simulations of Dansgaard–Oeschger dynamics.

Background: Palliative care is not accessed by all those who can benefit from it. Survey aim: To explore awareness of palliative care and related services among UK oncology out-patients, and to analyse the relationship between demographic characteristics and knowledge. Design: Cross-sectional interview-based survey. Analysis comprised univariate and multiple logistic regression. Participants and settings: Oncology out-patients receiving curative treatments at two district general hospitals in north-west London between December 2004 and April 2005. Results: A total of 252 (94%) eligible clinic patients were interviewed. Only 47 (18.7%) patients recognised the term ‘palliative care’, but 135 (67.8%) understood the role of the hospice, and 164 (66.7%) understood the role of Macmillan nurses. Age-adjusted multiple logistic regression showed that recognizing the term ‘palliative care’ was more likely among the most socially and materially affluent patients than those who were the poorest (OR: 8.4, CI: 2.17-31.01, p =0.002). Understanding the role of Macmillan nurses was also more likely among the most socially and materially affluent patients compared with the poorest patients (OR: 7.0, CI: 2.41-18.52, p <0.0001), and was independently less likely among patients from black and minority ethnic groups than those who were classified as being white British (OR=0.5, CI:0.25-0.96, p =0.04). Conclusions: Awareness of palliative care and related services was low among black and minority ethnic groups, and the least affluent.

The Uniontown, Alabama Community Health Project trained and facilitated Community Health Advisors (CHAs) in conducting a theory-based intervention designed to reduce the risk for cardiovascular disease (CVD) among rural African-American women. The multiphased project included formative evaluation and community organization, CHA recruitment and training, community intervention and maintenance. Formative data collected to develop the training, intervention and evaluation methods and materials indicated the need for programs to increase knowledge, skills and resources for changing behaviors that increase the risk of CVD. CHAs worked in partnership with staff to develop, implement, evaluate and maintain strategies to reduce risk for CVD in women and to influence city officials, business owners and community coalitions to facilitate project activities. Process data documented sustained increases in social capital and community capacity to address health-related issues, as well as improvements in the community’s physical infrastructure. This project is unique in that it documents that a comprehensive CHA-based intervention for CVD can facilitate wide-reaching changes in capacity to address health issues in a rural community that include improvements in community infrastructure and are sustained beyond the scope of the originally funded intervention.

Balcer-Kubiczek, E. K., Harrison, G. H., Davis, C. C., Haas, M. L. and Koffman, B. H. Expression Analysis of Human HL60 Cells Exposed to 60 Hz Square- or Sine-Wave Magnetic Fields. A total of 960 complementary DNA (cDNA) clones from an HL60 cell cDNA library were screened to discover genes that were differentially expressed in HL60 cells exposed to 60 Hz square-wave magnetic fields (MFs) compared to sham-exposed cells. Square-wave fields are rich in odd harmonic frequency content. We used a two-gel cDNA library screening method (BIGEL) to identify treatment-induced alterations in gene expression. Four cDNA clones were tentatively identified as differentially expressed after exposure to square-wave MFs at 2 mT for 24 h. BIGEL-identified genes (GenBank accession number) corresponding to these clones were: TI227H (D50525), EST Homo sapiens partial cDNA (Z17814), human ribosomal protein S13 (L01124), and AICAR transformylase mRNAs (D82348). The differences in mRNA levels were not confirmed in test compared to experimental cells by Northern analysis. In other experiments, we used concurrent exposure to 60 Hz sine- or square-wave MFs (0 or 2 mT, duration of 3 or 24 h, no postexposure delay). In addition to the four BIGEL genes, we also investigated MYC, HSP70, RAN and SOD1. In the case of MYC and HSP70, square-wave MFs appeared to exhibit more marked alterations when compared to sinusoidal waveforms, but the overall results indicated no effect of possible differential magnetic-field-induced expression of all eight genes. In contrast, alterations of mRNA levels were observed for seven genes after exposure to X irradiation, hyperthermia and TPA. These results are contrary to previously proposed similarities between the action of these agents and MF effects on gene transcription.

A one-hour infusion of 0.25 micrograms/kg urogastrone administered to seven patients with duodenal ulceration resulted in significant reduction of basal acid secretion (p less than 0.05) but was without significant effect on basal pepsin and intrinsic factor secretion or on serum gastrin concentration. In another group of five patients with duodenal ulceration a one-hour infusion of urogastrone was given on five successive days. On day 1 and 5 urogastrone was administered after establishing a plateau response to intravenous pentagastrin 1.2 micrograms/kg/h. A mean reduction of 65% in acid output during the urogastrtone infusion was seen on day 1 and this was maintained during the next hour. On day 5 the pentagastrin-stimulated acid output was less than on day 1 and a further significant decrease was noted after urogastrone. Pepsin and intrinsic factor output were also significantly inhibited. There was no change in fasting serum gastrin or urogastrone concentration.