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Coastal dunes are effective natural buffers against climate change-induced sea-level rise and storminess. Coastlines characterised by the presence of blowouts at the beach-dune interface may be more susceptible to coastline retreat through the enhanced landward transport of beach and foredune sediment. Blowouts are highly effective transport pathways, but the dynamics of aeolian sediment transport governing their evolution are poorly understood. Their morphological form is indicative of aeolian transport, and the propensity of their topography to modify airflow sufficiently to support transport has been extensively researched. Although there is a growing number of studies detailing blowout sediment flux, those involving synchronous measurement of flow and sediment movement from the beach into the dune field are rare.This study examined airflow and sediment transport dynamics at the beach-dune interface of a trough blowout at Sefton Dunes, northwest England. A dense array of 3D sonic anemometers were co-located with transport sensors and deployed during an oblique onshore wind event. Instantaneous flow and transport dynamics were measured on the back beach, the adjacent upwind foredune, and within the throat of the blowout. Strong alongshore deflected airflow across the upwind foredune led to high-intensity sediment transport into the blowout throat. Inside the blowout throat, airflow and transport displayed extremely high spatial and temporal variability across the relatively confined throat area. Airflow speeded up close to the upwind blowout wall but sped ‘down’ close to the exposed (downwind) blowout wall. Transport (expressed in counts min-1 and Activity Parameter) showed low correlations with a range of wind variables such as wind speeds and TKE. Transport intensity followed a general pattern opposite wind speeds, with lower transport intensities close to the upwind blowout wall and higher transport intensities close to the downwind blowout wall area. Multiple topographically-forced flow modifications were observed (particularly at the blowout throat), and relatively minor 10-20° directional shifts led to large variations in flux intensity within the blowout. Results have provided detailed, high temporal, and spatial insights into how beach sediment is delivered to the blowout throat area and then driven landwards and reveals how foredune blowouts help facilitate beach sediment bypassing through foredunes, contributing to medium-scale coastal dune evolution behaviour.

Shoreline vectors are extracted from TerraSAR-X imagery based on the identification of peak backscatter intensity levels. The vectors are being catalogued and analysed to assess the accuracy/suitability of SAR imagery for identifying coastal erosion hotspots and for monitoring coastal change as input to forecasting models. The technique is being developed, tested and refined using data collected from three study sites on the west coast of Ireland (Brandon Bay; Clew Bay; Galway Bay).The shoreline vectors are extracted from both archived and tasked TerraSAR-X imagery. The extracted shorelines are being validated using a combination of: 1) panchromatic and multispectral satellite imagery (VHR1 & VHR2), 2) panchromatic and RGB aerial imagery (VHR1), 3) LiDAR data and 4) repeat DGPS field survey data. In addition, these shoreline vectors are also being compared with equivalent extractions from other very high-resolution X-band SAR imagery (Cosmo-SkyMed) and high-resolution C-band and L-band SAR imagery (RADARSAT-2, ALOS PALSAR). The spatial accuracy of the extracted shorelines from tasked acquisitions will be further assessed using temporarily installed corner reflectors at a selection of the study sites.SAR acquisition parameters (orbit pass direction, incidence angle, polarisation) and a selection of speckle noise reduction filters (e.g. Boxcar, Frost, Lee) were evaluated to determine the optimum combination for coastal sites with different physical characteristics.Results are presented in high-definition video format using a combination of GIS, Earth browser and 3D visualisation platforms.

Background: Levels of psychological distress appear to be increasing in the workplace, in parallel with the growth of employee assistance programme (EAP) provision offering a range of talking treatments. However, such growth takes place in the absence of a substantive body of supporting research evidence despite a quarter of a decade of research activity. Aims: To analyse a national sample of EAP data and profile relative service quality on a set of key service indicators. Method: CORE System data profiles of over 28,000 clients were voluntarily donated by six EAP service providers. An established benchmarking methodology was used to assess the relative quality of EAP service provision compared with published CORE System benchmarks for NHS primary care and UK higher education student counselling services. Results: High quality data profiled an EAP service clientele who were quantifiably distressed, accessed treatment quickly, with the majority completing treatment and demonstrating high rates of ...

A 22nd Dynasty (945–730 BC) cartonnage mummy case was studied to identify the materials and methods used in its fabrication and to better understand its conservation requirements. Analysis of the organic and inorganic materials by microscopy, energy dispersive x-ray spectroscopy, gas chromatography-mass spectrometry, and Fourier transform infrared spectroscopy revealed that traditional Egyptian pigments characteristic of the period were used over layers of calcite ground and linen. Further study aided by x-radiography revealed that prior to insertion of the mummified body of Pa-di-mut, the case was fabricated over a removable mud model. A review of archives from the time of the case's excavation, combined with the examination and analysis, led to the development of a conservation strategy that combined accepted practices of stabilization with passive measures to promote preservation.

Films of Liquitex gloss medium, an acrylic dispersion polymer product, have been reported to become turbid slowly due to the formation of microscopic crystalline inclusions. This report describes the analysis of the melting point, morphology, solubility and infrared absorption spectrum of these included crystals and of the crystalline solids extracted from the acrylic films with water. The results of these analyses indicate that the crystals that cause turbidity in these acrylic films are poly (ethane-1,2-diol) [poly (ethylene glycol)] type compounds. A mechanism by which these crystals form in the films is described, and the conditions that favor crystallization are identified. These parameters suggest avenues which might be explored in seeking appropriate treatments to prevent or remedy the turbidity in acrylic media films.

At the Neolithic archaeological site at Liangzhu in China, located 16 kilometers northwest of Hangchou in Cheking province, many objects of stone, jade, and black pottery were discovered between 1936 and 1939. While the exact date of the Liangzhu culture is uncertain, it is considered to be between 3500 and 2000 BC. A characteristic feature of the Liangzhu-culture pottery is a thin black finish and a layered structure of the body consisting of a black core sharply changing to a gray or red band ending in the black surface.The focus of this paper is to explain why the cores of the vessels are black and why the colored bands occur and what they indicate about the firing conditions of the pottery. Analyses were ca rried out using SEM, electron-beam microprobe, X-ray diffraction, photo-electron spectroscopy, and polarizing microscopy. From this evidence, it is clear thait a clay vessel containing abundant charcoal was thrown on the wheel and then fired under reducing conditions so that charcoal was retained and iron reduced. Just before completion of the firing or during the cooling phase, air was allowed to enter the kiln and a limited thickness of the outer core was oxidized. Then, for decorative purposes, the surface was heavily smoked, and/or a thin iron-containing slip layer was reduced in smoke and burnished.

(1998). JOHN SINGER SARGENT'S FORGOTTEN MURAL CYCLE, THE TRIUMPH OF RELIGION AT THE BOSTON PUBLIC LIBRARY. Studies in Conservation: Vol. 43, Painting Techniques History, Materials and Studio Practice: Summaries of the Posters at the Dublin Congress, 7-11 September 1998, pp. 25-25.

Carefully documented specimens of ancient Persian pigments taken from the surface of the limestone reliefs at Persepolis and Pasargadae, and several bulk specimens excavated at Persepolis, have been identified as Egyptian blue, malachite, hematite, cinnabar and yellow ochre. A separate group of excavated materials, also thought to have been used as pigments, were determined to be Egyptian blue, azurite, the rare green mineral tyrolite, orthorhombic sulfur, a calcite-yellow ochre mixture, and realgar. These materials were studied and identified using a combination of optical and scanning electron microscopic, atomic emission spectrographic, X-ray diffractionand fluorescence, and Fourier transform infrared spectrophotometric techniques.