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This article argues for the need to significantly adjust the process and focus of the educational thesis and dissertation to better match the preparation and needs of students who are practitioners in order to help these students become stronger and better educators and leaders. To that end, the article presents innovative approaches to improve experiences for graduate students who are developing, conducting and completing master’s degree theses and doctoral dissertations in the field of education. The vast majority of students who pursue master’s or doctoral degrees in education do not intend to become researchers or university faculty. Rather, most of these students are looking to improve their skills as teachers and educational leaders, and will likely never conduct a major research effort beyond the thesis or dissertation. While these students have a great deal of practical experience in their field, most of them have had little or no exposure to graduate level research, scholarly literature or academic writing. Recognizing that research skills including data collection and analysis, and academic writing are essential skills for all graduate students including those in educational programs, these skills alone are inadequate in preparing educators for the realities they face as they work to conduct multi-tiered and multi-faceted research that will affect positive change and contribute to the field to improve overall student success. For many of these students the thesis and dissertation, while a significant requirement for the degree, are viewed as major “hurdles” that are too often disconnected from the realities and complexities of the classroom and administrative office. Appropriate theoretical and conceptual frameworks are used to examine how the educational thesis and dissertation process can be improved to better serve the needs of educational practitioners. This includes the use of Role AcquisitionTheory (Thornton & Nardi, 1975) to examine and help facilitate the intrinsic change process in graduate students in education during the thesis and dissertation process. Transformative Learning Framework (Cranton, 2016) is used to better understand and advance developmental changes and scaffolding that are necessary to examine problematic frames of reference, openly reflect, and to emotionally change from the experience. The Loss/Momentum Framework (RP Group, 2012) is used in two separate ways; first to scrutinize specific institutional barriers and supports that exist in graduate and doctoral programs in education as well throughout the university that influence the process of completing the thesis and dissertation. Second, it is used to identify and examine individual characteristics, skills, and attributes of these students that serve as either barriers or assets to completing a meaningful thesis or dissertation. Practical recommendations for improving the educational thesis and dissertation process are provided, and mentoring and strategic coaching approaches discussed.

Free-ocean CO2 enrichment (FOCE) experiments have been deployed in marine ecosystems to manipulate carbonate system conditions to those predicted in future oceans. We investigated whether the pH/carbonate chemistry of extremely cold polar waters can be manipulated in an ecologically relevant way, to represent conditions under future atmospheric CO2 levels, in an in-situ FOCE experiment in Antarctica. We examined spatial and temporal variation in local ambient carbonate chemistry at hourly intervals at two sites between December and February and compared these with experimental conditions. We successfully maintained a mean pH offset in acidified benthic chambers of −0.38 (±0.07) from ambient for approximately 8 weeks. Local diel and seasonal fluctuations in ambient pH were duplicated in the FOCE system. Large temporal variability in acidified chambers resulted from system stoppages. The mean pH, Ωarag and fCO2 values in the acidified chambers were 7.688 ± 0.079, 0.62 ± 0.13 and 912 ± 150 µatm, respectively. Variation in ambient pH appeared to be mainly driven by salinity and biological production and ranged from 8.019 to 8.192 with significant spatio-temporal variation. This experiment demonstrates the utility of FOCE systems to create conditions expected in future oceans that represent ecologically relevant variation, even under polar conditions.

Anthropogenic inputs of CO2 are changing ocean chemistry and will likely affect calcifying marine organisms, particularly aragonite producers such as pteropods. This work seeks to set a benchmark analysis of pteropod shell properties and variability using nanoindentation and electron microscopy to measure the structural and mechanical properties of Subantarctic pteropod shells (Limacina helicina antarctica) collected in 1998 and 2007. The 1998 shells were collected by a sediment trap deployed at 2000 m, 47°S, 142°E, and the 2007 shells were collected using nets from mixed-layer waters in the region (44°–54°S, 140°–155°E). Transmission electron microscopy revealed that the shells are composed of a polycrystalline structure, and no obvious porosity was visible. The hardness and modulus of the shells were measured using shell cross-section nanoindentation, across various regions of the shell from the inner to outer whorl. No change in mechanical properties was found with respect to the region of the shell cross-section probed. There was no statistically significant difference in the mean modulus or hardness of the shells between the 1998 and 2007 data sets. No major changes in the mechanical properties of these pteropod shells were detected between the 1998 and 2007 data sets, and we discuss the possible biases in the sampling techniques in complicating our analysis. However, quantifying the mechanical properties and microstructure of calcified may still provide insights into the responses of calcification to environmental changes, such as ocean acidification.

The Grand Jeu (literally translated "The Great Game") was a group of artists, poets, and writers that published an eponymous periodical in Paris between 1928 and 1930. Simplisme was intended as a talisman against the impending threat of adulthood and it was during this period that Daumal and Gilbert-Lecomte became absorbed in a discourse of psychology, Bergsonism, metaphysics, Hindu, and Occidental mysticism. These include paramnesia; depersonalisation or states of dissociation from a coherent self; and the idea of dreams as a form of transpersonal memory. Despite the emphatic message of revolt, however, the Grand Jeu's interest in metaphysics and mysticism drew great suspicion from the surrealist group. In closing, in line with the paradoxical character of the Grand Jeu, this chapter turns to an opening, sketching out a possibly fruitful new perspective on the Grand Jeu by outlining how the group's thought can be approached from a Deleuzian angle.

Domestic violence is a pervasive, significant social and public health issue that often has physical, emotional, social, legal, economic and political ramifications. The present qualitative study sought to address the paucity of knowledge in the domestic violence literature by identifying the psychological impact of the Family Court process on women who have left abusive relationships. A thematic analysis was conducted on the narratives of 15 women who had left abusive relationships and who had, or were currently, engaged with the Family Court. The results revealed that the experience of engaging with the court process caused considerable distress for the women. Principal themes related to fear of the ex-partner and having to confront him at hearings, constantly reliving the relationship via affidavits, and the insensitivity of some legal professionals to the difficulties experienced by women confronted with these experiences.

Free-ocean CO2 enrichment (FOCE) systems are designed to assess the impact of ocean acidification on biological communities in situ for extended periods of time (weeks to months). They overcome some of the drawbacks of laboratory experiments and field observations by enabling (1) precise control of CO2 enrichment by monitoring pH as an offset of ambient pH, (2) consideration of indirect effects such as those mediated through interspecific relationships and food webs, and (3) relatively long experiments with intact communities. Bringing perturbation experiments from the laboratory to the field is, however, extremely challenging. The main goal of this paper is to provide guidelines on the general design, engineering, and sensor options required to conduct FOCE experiments. Another goal is to introduce xFOCE, a community-led initiative to promote awareness, provide resources for in situ perturbation experiments, and build a user community. Present and existing FOCE systems are briefly described and examples of data collected presented. Future developments are also addressed as it is anticipated that the next generation of FOCE systems will include, in addition to pH, options for oxygen and/or temperature control. FOCE systems should become an important experimental approach for projecting the future response of marine ecosystems to environmental change.

The impact of ocean acidification on key ocean calcifiers is predicted to be imminent, particularly in high-latitude ecosystems. Long-term field observations are essential to ground truth predictions of change in regional ecosystems. Here, we report on aragonitic pteropods collected to sediment traps at 800 m depth at 54°S, 140°E in the Polar Frontal Zone (PFZ) of the Southern Ocean from 1997 to 2007. Statistically significant trends were not identified in either mass or number flux from 1997 to 2007; however, differences emerged in decadal trends seen in shell weight for each of the three common taxa collected: Limacina helicina antarctica forma antarctica shells became significantly lighter (P

Teniswood, C. M. H., Roberts, D., Howard, W. R., and Bradby, J. E. 2013. A quantitative assessment of the mechanical strength of the polar pteropod Limacina helicina antarctica shell. – ICES Journal of Marine Science, 70: . This work directly measures the mechanical properties of pteropod shells collected from the Southern Ocean on the 2007 midsummer Subantarctic Zone Sensitivity to Environmental Change (SAZ-Sense) voyage. Shells from the common Southern Ocean pteropod Limacina helicina antarctica were subjected to mechanical analyses in combination with detailed morphological studies. Average hardness and modulus of 2.30 ± 0.07 GPa and 45.27 ± 0.91 GPa, respectively were calculated from several hundred nanoindentation measurements taken from multiple positions across twelve shells of the same species collected under identical conditions. Quantitative data such as these are critical to establish a reference point for future comparative studies and to both understand and evaluate the implications of further ocean acidification on the structural integrity of these common polar calcifiers, particularly in light of their role in the Southern Ocean carbon cycle and food web.

Empirically assessing sanitary and phytosanitary regulations has proven difficult because most data sources indicate whether a regulation exists but provide no information on the type or importance of the respective measure. In this article, we construct a novel database of U.S. phytosanitary measures and match these to 47 fresh fruit and vegetable product imports from 89 exporting countries over the period 1996--2008. A product-line gravity equation that accounts for zero trade flows is developed to investigate the trade impact of different pest-mitigation measures. While the results suggest that phytosanitary treatments generally reduce trade, the actual restrictiveness of these measures diminishes dramatically as exporters accumulate experience, and it vanishes when exporters reach a certain threshold. The results have important policy implications considering the number of empirical studies that find a negative impact of non-tariff measures on trade. Copyright 2013, Oxford University Press.

Antarctic snow samples collected from the Wilkins Runway, c. 50 km inland from the Windmill Islands, East Antarctica, contain aeolian-derived diatoms. The diatom assemblage preserved is exclusively of marine origin. As diatoms are excellent indicators of source conditions, we are able to confirm that an unusual weather event, with anomalous north-westerly winds blowing at around 10 m s-1, resulted in the deposition of coastal marine species at the Wilkins Runway. The composition of the floral assemblage collected indicate that the parent water mass was from a coastal marine region undergoing typical Antarctic summer conditions with periods of both consolidated sea ice and open water. On inspection of available satellite imagery, these conditions were found upwind of the deposition site. This study provides a methodology for diatoms found within ice cores to be identified and the source region to be determined. It also provides evidence for a large-scale aeolian deposition of marine diatoms to an ice sheet, which may have implications for the interpretation of controversial marine diatoms found in sediments that have been used as evidence for the retreat of the East Antarctic Ice Sheet.

Pteropods were identified from epipelagic net and trawl samples in the Sub-Antarctic Zone during the 2007 mid-summer (January 17–February 20) Sub-Antarctic Zone Sensitivity to Environmental Change (SAZ-Sense) voyage, as well as in a moored sediment trap in the same region. Overall pteropod densities during SAZ-Sense were lower than those reported for higher-latitude Southern Ocean waters. The four major contributors to the Sub-Antarctic Zone pteropod community during the SAZ-Sense voyage, Clio pyramidata forma antarctica, Clio recurva, Limacina helicina antarctica and Limacina retroversa australis, accounted for 93% of all pteropods observed. The distribution of the two dominant pteropods collected in the Sub-Antarctic Zone, L. retroversa australis and C. pyramidata forma antarctica, is strongly related to latitude and depth. L. retroversa australis is typical of cold southern (50–54°S) polar waters and C. pyramidata forma antarctica is typical of shallow (top 20 m) Sub-Antarctic Zone waters. A moored sediment trap deployed to 2100 m at 47°S, 141°E in 2003/04 showed the pteropod flux in the Sub-Antarctic Zone had late-Spring and mid-summer peaks. The diversity, abundance and distribution of pteropods collected during SAZ-Sense provide a timely benchmark against which to monitor future changes in SAZ ocean pteropod communities, particularly in light of predictions of declining aragonite saturation in the Southern Ocean by the end of the century.

Anthropogenic inputs of CO2 are altering ocean chemistry and may alter the role of marine calcifiers in ocean ecosystems. Laboratory research and ocean models suggest calcifiers in polar waters are especially at risk, particularly pteropods: pelagic aragonite-shelled molluscs. However, baseline data for natural populations of pteropods are limited, especially for polar and sub-polar waters. In order to establish baseline data on diversity, preservation state and shell flux of in situ populations of Sub-Antarctic Southern Ocean pteropods, we deployed sediment traps above (1,000 m) and below (2,000 m) the aragonite saturation horizon (ASH) (currently at 1,200 m) from 1997 to 2006 at 47°S, 142°E. We identified seven pteropod taxa. We applied a shell opacity index to each shell collected and found 50% of shells collected above the ASH to be in pristine condition but only 3% of the shells collected below the ASH showed such a high degree of preservation. We estimated pteropod shell mass fluxes for the region (0.17–4.99 mg m−2 day−1), and we identified significant reductions in shell flux for Limacina helicina antarctica forma rangi and Clio recurva to the trap series above the ASH and for Limacina helicina antarctica forma rangi and Limacina helicina antarctica forma antarctica to the trap series below the ASH over the interval 1997–2006. Our data establish a temporal and vertical snapshot of the current Sub-Antarctic pelagic pteropod community and provide a baseline against which to monitor Southern Ocean pteropods responses, if any, to changing ocean conditions projected for the region in the coming decades.

To date, little is known about the relative importance of dispersal related versus local factors in shaping microbial metacommunities. A common criticism regarding existing datasets is that the level of taxonomic resolution might be too coarse to reliably assess microbial community structure and study biogeographical patterns. Moreover, few studies have assessed the importance of geographic distance between habitats, which may influence metacommunity dynamics through its effect on dispersal rates. We applied variation partitioning analyses to 15 separate regional datasets on diatoms found in lakes in Eurasia, Africa and Antarctica. These analyses quantified the relative contributions of dispersal related and local factors in determining patterns of taxonomic turnover at the species and at the genus level. In general, results were similar at both taxonomic levels. Local environmental factors accounted for most of the explained variation (median=21%), whereas dispersal related factors were much less important (median of significant fractions=5.5% variation explained) and failed to significantly explain any variation, independent of the environmental variables, in the majority of the datasets. However, the amount of variation explained by dispersal related factors increased with increasing geographic distance and increasing taxonomic resolution. We extrapolated our regional scale observations to the global scale by combining the regional datasets into a global dataset comprising 1039 freshwater lakes from both hemispheres and spanning a geographic distance of over 19 000 km. At this global scale, taxonomic turnover was lowest in highly connected habitats, once environmental factors were partialled out. In common with many other studies of macro-organisms, these analyses showed that both dispersal related and local variables significantly contribute to the structure of global lacustrine diatom communities.

This article reviews the performance of the World Trade Organization in the oversight of national regulatory decisions affecting agricultural and food trade. A picture emerges of modest international disciplines on the regulatory decisions of sovereign nations and the need for ongoing improvements. A road map to regulations is presented and empirical assessments of the effects of technical regulation on trade are reviewed. Conflicts over sanitary and phytosanitary barriers raised in the relevant World Trade Organization committee are summarized and formal dispute settlement cases involving technical trade barriers are evaluated. Drawing on these reviews, suggestions are made for improving international food regulation.

This study presents compelling evidence for a diverse and abundant seabed community that developed over the course of the Holocene beneath the Amery Ice Shelf, East Antarctica. Fossil analysis of a 47 cm long sediment core revealed a rich modern fauna dominated by filter feeders (sponges and bryozoans). The down-core assemblage indicated a succession in the colonisation of this site. The lower portion of the core (before ~9600 yr BP) was completely devoid of preserved fauna. The first colonisers (at ~10 200 yr BP) were mobile benthic organisms. Their occurrence was matched by the first appearance of planktonic taxa, indicating a retreat of the ice shelf following the last glaciation to within sufficient distance to advect planktonic particles via bottom currents. The benthic infauna and filter feeders emerged during the peak abundance of the planktonic organisms, indicating their dependence on the food supply sourced from the open shelf waters of Prydz Bay. Understanding patterns of species succession in this environment has important implications for determining the potential significance of future ice shelf collapse.

Samples of marine ice were collected from the Amery Ice Shelf, a large embayed ice shelf in East Antarctica, during the Austral summer of 2001–2002. The samples came from a site ∼90 km from the iceberg calving front of the shelf, where the ice is 479 m thick and the lower 203 m is composed of accreted marine ice. Protists identified within the marine ice layer of the Amery Ice Shelf include diatoms, chrysophytes, silicoflagellates and dinoflagellates. The numerical dominance of sea ice indicator diatoms such as Fragilariopsis curta, Fragilariopsis cylindrus, Fragilariopsis rhombica and Chaetoceros resting spores, and the presence of cold open water diatoms such as Fragilariopsis kerguelensis and species of Thalassiosira suggest the protist composition of the Amery marine ice is attributable to seeding from melting pack and/or fast ice protist communities in the highly productive waters of Prydz Bay to the north.

Research in East Antarctica has shown several recent environmental changes that may be linked to human impacts on climate. In order to detect the influence and context of these changes on coastal aquatic ecosystems we examined lake sediment cores from three lakes in the Windmill Islands, East Antarctica; Beall Lake, Holl Lake and ȁ8Lake Mȁ9. Cores were sectioned at␣2.5 mm intervals. Their diatom species composition was examined to detect changes in lake salinity using a diatom-salinity transfer function, and their algal pigment content was examined to detect photoautotrophic community responses to environmental change. Results showed that Holl Lake originated in a depression exposed by Holocene recession of the continental ice sheet and that Beall Lake and Lake M originated as isolated marine basins formed by changes in relative sea level. A general late Holocene trend of declining lake salinity was evident in all three lakes, interrupted by one short-term high salinity event in Beall Lake. This is consistent with a long-term positive moisture balance. This general decline in salinity has been followed by a remarkable recent rapid increase in salinity in all three lakes in the last few decades. We speculate that this rapid increase in salinity might be linked to changes taking place in the region including feedbacks resulting from decreasing sea ice extent as recorded in the nearby Law Dome ice core, and positive feedbacks in the catchments whereby reduced snow cover has led to decreased albedo, which in turn has caused increased evaporation and sublimation. Collectively these changes have shifted the lakes across a threshold from positive to negative moisture balance. A minor, but not rapid shift in the abundance of diatom pigments relative to pigments from green algae and cyanobacteria was also detected suggesting that some changes in photoautotrophic community composition have occurred. Measurements of modern nutrient levels are also higher than would be expected in Beall Lake and Holl Lake, given the extremely low sediment accumulation rates. This may be associated with a c. 300% increase in the population of Adelie penguins in the Windmill Islands recorded since the 1950s, or may a first signs of a rapid increase in catchment development and associated lake productivity as experienced in Antarctic and Arctic lakes subject to recent rapid regional warming. The most marked feature of the records is the rapid increase in salinity in all three lakes in␣the last few decades, which has occurred in lakes both with and without resident penguin populations.

1. Many coastal lagoons in eastern Australia have changed as a result of recent human activities. However, it is often difficult to determine the extent of change and the ecological implications. A palaeoecological approach allows a quantitative assessment of how an aquatic ecosystem changes and responds to human impacts beyond what is possible with historical data or monitoring programmes. 2. Orielton Lagoon (south-east Tasmania, Australia) is a Ramsar-listed coastal wetland of international importance for conservation. This study was undertaken at the site to determine whether recent anthropogenic hydrological modifications to the lagoon had influenced its ecology, particularly salinity, and compromised its Ramsar status. 3. A diatom–salinity transfer function was constructed from a training data set of 96 diatom taxa from 34 sampling sites in 19 lagoons along the east coast of Tasmania. 4. The salinity of Orielton Lagoon has changed in response to a causeway constructed across its mouth, which has transformed the lagoon from an open marine environment to an enclosed, virtually stagnant, brackish water body. 5. These changes have compromised the protected coastal wetland status of Orielton Lagoon. Environmental remediation attempts have since partially restored the natural hydrology of the lagoon and it is now returning towards the state it was in prior to causeway construction. 6. A palaeoecological approach using diatoms was found to be successful in reconstructing recent salinity changes and investigating human impacts on Orielton Lagoon over the last 50–55 years.

Technical regulations are increasingly visible in agricultural trade, yet their idiosyncratic nature has limited prior aggregate analysis. This article draws on a unique data source for systematic enumeration of the technical regulations questioned by one exporter among all of its trading partners in mid-1996. Political economy analysis indicates that barriers decrease when the relative contribution of agriculture to an economy increases, when the anticipated future level of protection through other forms of government intervention increases, and when economies are more open. Despite increased scrutiny and discipline by the World Trade Organization, technical barriers remain a significant impediment in world agricultural markets.

A mid-Holocene climate optimum is inferred from a palaeosalinity reconstruction of a closed saline lake (Beall Lake) from the Windmill Islands, East Antarctica using an expanded diatom salinity weighted averaging (WA) regression and calibration model. The addition of 14 lakes and ponds from the Windmill Islands, East Antarctica, to an existing weighted averaging regression and calibration palaeosalinity model of 33 lakes from the Vestfold Hills, East Antarctica expands the number of taxa and lakes and the range of salinity in the existing model and improves the model's predictive ability. This improved model was used to infer Holocene changes in lake water salinity in Beall Lake, Windmill Islands. Six changes in diatom-inferred salinity in Beall Lake are put into broad chronological context based on three radiocarbon dates: as the East Antarctic Ice Sheet (EAIS) retreated from the Windmill Islands during the early Holocene (∼9000–8130 corr. yr BP), Beall Lake formed as a melt water-fed freshwater lake, which gradually became more saline as marine influence increased from ∼8000 corr. yr BP. Between ∼8000 and 4800 corr. yr BP, the diatom assemblage included planktonic marine taxa such as Chaetoceros spp. and cryophilic taxa such as Fragilariopsis cylindrus, which indicate favourable summer growth conditions. A mid-Holocene warm period produced a climate that was warmer and more humid with increased precipitation and snow accumulation. This is reflected in the Beall Lake core as a reduction in the salinity of the lake diatom assemblage from ∼4800–4600 corr. yr BP. Holocene isostatic uplift rates in the Windmill Islands vary from 5–6 m/1000 yr. By applying this uplift rate, it is calculated that the bedrock would have risen above sea level by ∼4000 yr BP. The Beall Lake core diatom assemblage from ∼4600–2900 corr. yr BP includes both marine cryophilic and planktonic taxa together with freshwater benthic and planktonic lacustrine taxa. This mix of species indicates the emergence of the lake from the sea around ∼4600 corr. yr BP. From ∼2800 corr. yr BP, retreat of the ice margin led to increasing melt water inputs and associated freshening of the lake basin until ∼1900 corr. yr BP. The lake basin had no oceanic influence by this time, allowing a terrestrial freshwater flora to establish and thrive for the next ∼1000 yr. At ∼1850 corr. yr BP, a sudden and rapid salinity change is evident in Beall Lake. A late Holocene warm period between 2000 and 1000 yr BP has been observed in ice core records from Law Dome (an ice cap abutting the Windmill Islands to the east and north). It is therefore inferred that, at ∼1850 corr. yr BP, summer temperatures within the Beall Lake catchment area were much higher than present summer temperatures. The climate optimum identified in the Beall Lake core ∼4800 yr BP confirms mid-Holocene warming of the Windmill Islands and suggests a synchronous mid-Holocene climate optimum occurred across coastal East Antarctica. In addition, the abrupt climate change inferred at ∼1850 yr BP suggests that higher resolution sampling of sediment cores from coastal East Antarctic limnological oases will provide more evidence of rapid climate change events over coastal East Antarctica in future.

The late Quaternary palaeoenvironmental history of the southern Windmill Islands, East Antarctica, has been reconstructed using diatom assemblages from two long, well-dated sediment cores taken in two marine bays. The diatom assemblage of the lowest sediment layers suggests a warm climate with mostly open water conditions during the late Pleistocene. During the following glacial, the Windmill Islands were covered by grounded ice preventing any in situ bioproductivity. Following deglaciation, a sapropel with a well-preserved diatom assemblage was deposited from ∼10 500 cal yr BP. Between ∼10 500 and ∼4000 cal yr BP, total organic carbon (Corg) and total diatom valve concentrations as well as the diatom species composition suggest relatively cool summer temperatures. Hydrological conditions in coastal bays were characterised by combined winter sea-ice and open water conditions. This extensive period of glacial retreat was followed by the Holocene optimum (∼4000 to ∼1000 cal yr BP), which occurred later in the southern Windmill Islands than in most other Antarctic coastal regions. Diatom assemblages in this period suggest ice-free conditions and meltwater-stratified waters in the marine bays during summer, which is also reflected in high proportions of freshwater diatoms in the sediments. The diatom assemblage in the upper sediments of both cores indicates Neoglacial cooling from ∼1000 cal yr BP, which again led to seasonally persistent sea-ice on the bays. The Holocene optimum and cooling trends in the Windmill Islands did not occur contemporaneously with other Antarctic coastal regions, showing that the here presented record reflects partly local environmental conditions rather than global climatic trends.

The water chemistry of lake systems on the edge of the Antarctic continent responds quickly to changes in the moisture balance. This is expressed as increasing salinity and decreasing lake water level during dry periods, and the opposite during wet periods. The diatom composition of the lakes also changes with these fluctuations in salinity and lake water depth. This is important, as their siliceous remains become incorporated into lake sediments and can provide long-term records of past salinity using transfer functions. In order to develop transfer functions, diatoms and water chemistry data were inter-calibrated from five different East Antarctic oases, namely the Larsemann Hills, the Bolingen Islands, the Vestfold Hills, the Rauer Islands and the Windmill Islands. Results indicate that salinity is the most important environmental variable explaining the variance in the diatom flora in East Antarctic lakes. In oligo- saline lakes the variance is mainly explained by lake water depth. This dataset was used to construct a weighted averaging transfer function for salinity in order to infer historical changes in the moisture balance. This model has a jack-knifed r2 of 0.83 and a RMSEP of 0.31. The disadvantage of this transfer function is that salinity changes in oligo-saline lakes are reconstructed inaccurately due to the ‘edge effect’ and due to the low species turnover along the salinity gradient at its lower end. In order to infer changes in the moisture balance in these lakes, a second transfer function using weighted averaging partial least squares (with two components) for depth was constructed. This model has a jack-knifed r2 of 0.76 and a RMSEP of 0.22. Both transfer functions can be used to infer climate driven changes in the moisture balance in lake sediment cores from oligo-, hypo-, meso- and hyper-saline lakes in East Antarctic oases between 102–75°E. The transfer function for lake water depth is promising to track trends in the moisture balance of small freshwater lakes, where changes in shallow and deep-water sediments are readily reflected in changing diatom composition.

For nearly 40 years, the photographer Emila Medková (1928–1985) produced intimate and yet oblique images of textures and suggestive patterns inscribed across the surfaces of her native city of Prague. Medková was a member of the post-war Czech surrealist group, which boasts a notable history of weathering the fluctuating political and ideological pressures of first the Nazi occupation and then the Soviet era. Medková's work reflects the rich and various currents running through the development of photographic art and surrealism in pre- and post-war Czechoslovakia, and is identifiable by the combination of certain distinct elements: notably, the close-up attention to surface associated with the Czech New Objectivity movement; the documenting of the evocative corners of the city of Prague associated with the photography of pre-war surrealist Jindřich Štyrský; the exploration of a characteristically surrealist approach to visual analogy; and the black-humoured critique of reality that would become a defining characteristic of the Czech surrealist group. While Medková's work has very much been seen from within the history of the Czech surrealists' critique of assumed or imposed notions of reality, in the course of this essay we would like to suggest another route into her work that takes into account the feminist revision of art history in Eastern Central Europe over the last 15 years or so.

Platelet endothelial cell adhesion molecule-1 (PECAM-1) is a newly assigned member of the Ig-immunoreceptor tyrosine-based inhibitory motif superfamily, and its functional role is suggested to be an inhibitory receptor that modulates immunoreceptor tyrosine-based activation motif-dependent signaling cascades. In this study, we hypothesized that PECAM-1 plays an essential in vivo role as a counterregulator of immediate hypersensitivity reactions. We found that PECAM-1 was highly expressed on the surface of immature bone marrow mast cells and at a lower density on mature peritoneal mast cells. Examination of skin biopsies from PECAM-1+/+ and PECAM-1−/− mice revealed that absence of PECAM-1 did not affect mast cell development or the capacity of mast cells to populate tissues. To examine whether the absence of PECAM-1 would influence immediate hypersensitivity reactions, PECAM-1+/+ and PECAM-1−/− mice were presensitized with anti-DNP mouse IgE and then challenged 20 h later with DNP-BSA or PBS. PECAM-1−/− mice exhibited elevated serum histamine concentrations after Ag stimulation compared with PECAM-1+/+ mice, indicating an increased severity of systemic IgE-mediated anaphylaxis. PECAM-1−/− mice have increased sensitivity to local cutaneous IgE-dependent anaphylaxis compared with PECAM-1+/+ mice, as assessed by greater tissue swelling of their ears and mast cell degranulation in situ. PECAM-1−/− bone marrow mast cells showed enhanced dense granule serotonin release after FcεRI cross-linking in vitro. These results suggest that PECAM-1 acts as a counterregulator in allergic disease susceptibility and severity and negatively modulates mast cell activation.

Although considered pristine, Antarctica has not been impervious to hydrocarbon pollution. Antarctica’s history is peppered with oil spills and numerous abandoned waste disposal sites. Both spill events and constant leakages contribute to previous and current sources of pollution into marine sediments. Here we compare the response of the benthic diatom communities over 5 years to exposure to a commonly used standard synthetic lubricant oil, an alternative lubricant marketed as more biodegradable, in comparison to a control treatment. Community composition varied significantly over time and between treatments with some high variability within contaminated treatments suggesting community stress. Both lubricants showed evidence of significant effects on community composition after 5 years even though total petroleum hydrocarbon reduction reached approximately 80% over this time period. It appears that even after 5 years toxicity remains high for both the standard and biodegradable lubricants revealing the temporal scale at which pollutants persist in Antarctica.

The limnology and sedimentary diatom flora of fourteen lakes and ponds from the Windmill Islands, East Antarctica, is presented. Saline lakes, saline ponds and freshwater ponds are represented in this dataset. The Windmill Island lake diatom flora represents an intermediate floral assemblage between that of the freshwater lakes of the Larsemann Hills and the saline lakes of Vestfold Hills, East Antarctica. Variations within this assemblage are related to water chemistry variables in the Windmill Island lakes. In particular, a lakewater salinity/phosphate gradient can explain the variation observed in the sedimentary diatom flora of the lakes and ponds included in this study.

A high resolution mixed carbonate and siliciclastic sequence from DSDP Site 594 contains a detailed record of climate change in the late Pliocene. The sequence can be accurately dated by the LAD of Nitzschia weaveri, the LAD of Thalassiosira insigna, the LAD of T. vulnifica and the LAD of T. kolbei diatom datums. Carbonate content and δ18O signatures provide added resolution and place the sequence between isotope stages 100 and 92. The sequence contains well-preserved and diverse dinoflagellate cyst floras. Use of principal component (PCA) and canonical correspondence analyses (CCA) identifies changes in the assemblages that principally reflect warming and cooling trends. Species associated with warmer climates included Impagidinium patulum, I. paradoxum and I. sp. cf. paradoxum while those from cooler climates include Invertecysta tabulata and I. velorum. CCA is shown to be a valuable method of determining the past environmental preferences of extinct species such as I. tabulata.

A high-resolution record of evaporation for the last 650 years was derived from the diatom-salinity signal preserved in a sediment core taken from Ace Lake, Vestfold Hills (68° 28's, 78° 11'E), Antarctica. The seasonal oxygen isotope signal preserved in an ice core from Law Dome (66° 44'S, 112° 50'E), Antarctica, revealed a high-resolution summer temperature record for the same time period. The two proxies show highly correlated behaviour despite having significantly different climatic response mechanisms and a large geographic separation. The correlation observed between proxies based on such differing processes and analytical method ologies provides not only a climate record for the past 650 years that is both robust and regionally representative of coastal East Antarctica but also confirmation of the utility of reconstructions using these methods.

There is growing recognition of the communicative potential in many of the informal and idiosyncratic behaviors exhibited by children with developmental and physical disabilities. To assist in assessment and intervention planning, it would seem important to identify these potential communicative acts. To this end, the present article describes the development of the Inventory of Potential Communicative Acts (IPCA). The IPCA is an interview schedule designed to be completed by parents, teachers, and therapists of children with developmental and physical disabilities and severe communication impairment. It consists of 53 questions asking informants to indicate how the child communicates 10 distinct pragmatic functions. To date, pilot testing, development research, and field trials have involved 30 children. The results of this development work indicate that the IPCA is an efficient means of collecting accurate and verifiable data on the potential communicative acts of children with severe communication impairment associated with a range of developmental and physical disabilities. Use of the IPCA in communication assessment and intervention is discussed.

The granulocyte-macrophage colony-stimulating factor (GM-CSF) gene is part of a cytokine gene cluster and is directly linked to a conserved upstream inducible enhancer. Here we examined thein vitroandin vivofunctions of the human GM-CSF enhancer and found that it was required for the correctly regulated expression of the GM-CSF gene. An inducible DNase I-hypersensitive site appeared within the enhancer in cell types such as T cells, myeloid cells, and endothelial cells that express GM-CSF, but not in nonexpressing cells. In a panel of transfected cells the human GM-CSF enhancer was activated in a tissue-specific manner in parallel with the endogenous gene. Thein vivofunction of the enhancer was examined in a transgenic mouse model that also addressed the issue of whether the GM-CSF locus was correctly regulated in isolation from other segments of the cytokine gene cluster. After correction for copy number the mean level of human GM-CSF expression in splenocytes from 11 lines of transgenic mice containing a 10.5-kb human GM-CSF transgene was indistinguishable from mouse GM-CSF expression (99% ± 56% SD). In contrast, a 9.8-kb transgene lacking just the enhancer had a significantly reduced (P= 0.004) and more variable level of activity (29% ± 89% SD). From these studies we conclude that the GM-CSF enhancer is required for the correct copy number-dependent expression of the human GM-CSF gene and that the GM-CSF gene is regulated independently from DNA elements associated with the closely linked IL-3 gene or other members of the cytokine gene cluster.

The major influences on the salinity and water level of an Antarctic lake are parameterized and a palaeohydrological model linking the palaeosalinity of an Antarctic lake to the palaeohydrology of the lake is developed. Climatic change in this lake is recorded in the evaporative loss trend reconstructed from water level and lakewater salinity estimates. A decrease in salinity betweeñ700 and 200 years BP corresponds with c. 5 m increase in water level over the same time period. Both water level and lakewater salinity then stabilize in the last ~200 years BP. The palaeohydrological model derived from the changes inferred in salinity and water level shows that there is no significant change in evaporation for the last ~700 years but that a lower evaporation period is evident at ~150–200 years BP suggestive of a mild ‘Little Ice Age’ event in the Vestfold Hills.