Evaporite-karst processes, landforms, and environmental problems

Evaporite karst is widespread, but relatively unknown when compared with carbonate karst; this special issue addresses that lack of familiarity. Evaporite rocks have much higher solubilities and faster dissolution rates than carbonate rocks and they also commonly have lower mechanical strengths and more ductile reheologies. Many of these factors are dependent on the local hydrogeology, and when combined they can result in areas where karst features evolve on a human time scale, rather than a geological timescale. Karst collapse and subsidence are common in such areas, making them problematical for the local population. The evaporite-karst environment is very sensitive to changes in the local hydrology and hydrogeology, so that human factors such as groundwater extraction, drainage, and irrigation can act as triggering events for karst collapses. Some evaporite-karst features such as caves and saline springs have been beneficially exploited, but most of them, including sinkholes, subsidence, and groundwater degradation, pose a threat to the local environment and a hazard to development. The papers in this special issue of Environmental Geology arose from a successful session on Evaporite Karst convened by us at the Sixth International Conference on Geomorphology. This was held in Zaragoza, Spain, in September 2005 and was organised by Zaragoza University and the International Association of Geomorphologists (IAG; http://www.geomorph.org/). Authors of the twenty-eight presented abstracts were invited to submit full papers to this special issue. Nineteen papers were proposed and sixteen papers have been accepted and are published here

Northern Ireland Housing Market Areas

No abstract available

Identification, prediction and mitigation of sinkhole hazards in evaporite karst areas

Abstract Sinkholes usually have a higher probability of occurrence and a greater genetic diversity in evaporite terrains than in carbonate karst areas. This is because evaporites have a higher solubility, and commonly a lower mechanical strength. Subsidence damage resulting from evaporite dissolution generates substantial losses throughout the world, but the causes are only well-understood in a few areas. To deal with these hazards, a phased approach is needed for sinkhole identification, investigation, prediction, and mitigation. Identification techniques include field surveys, and geomorphological mapping combined with accounts from local people and historical sources. Detailed sinkhole maps can be constructed from sequential historical maps, recent topographical maps and digital elevation models (DEMs) complemented with building-damage surveying, remote sensing, and high-resolution geodetic surveys. On a more detailed level, information from exposed paleosubsidence features (paleokarst), speleological explorations, geophysical investigations, trenching, dating techniques, and boreholes, may help to recognize dissolution and subsidence features. Information on the hydrogeological pathways including caves, springs and swallow holes, are particularly important especially when corroborated by tracer tests. These diverse data sources make a valuable database - the karst inventory. From this dataset, sinkhole susceptibility zonations (relative probability) may be produced based on the spatial and temporal distribution of the features and good knowledge of the local geology. Sinkhole distribution can be investigated by spatial distribution analysis techniques including studies of preferential elongation, alignment and nearest neighbor analysis. More objective susceptibility models may be obtained by analyzing the statistical relationships between the known sinkholes and the conditioning factors, such as weather conditions. Chronological information on sinkhole formation is required to estimate the probability of occurrence of sinkholes (number of sinkholes/km² year). Such spatial and temporal predictions, derived from limited records and based on the assumption that past sinkhole activity may be extrapolated to the future, are non-corroborated hypotheses. Validation methods allow us to assess the predictive capability of the susceptibility maps and to transform them into probability maps. Avoiding the most hazardous areas by preventive planning is the safest strategy for development in sinkhole-prone areas. Corrective measures could be to reduce the dissolution activity and subsidence processes, but these are difficult. A more practical solution for safe development is to reduce the vulnerability of the structures by using subsidence-proof designs

Density Forecasting: A Survey

A density forecast of the realization of a random variable at some future time is an estimate of the probability distribution of the possible future values of that variable. This article presents a selective survey of applications of density forecasting in macroeconomics and finance, and discusses some issues concerning the production, presentation and evaluation of density forecasts.

Local attitudes in the treatment of low prognosis head and neck squamous cell carcinoma

The incidence of head and neck carcinoma in Malta is 2.44 per 100,000 population, with 5-year survival rate of 20%. International studies have however shown that head and neck squamous cell carcinoma (HNSCC) carries an average 30% survival rate. The cost of treatment of low prognosis HNSCC patients in Malta is roughly €62,500 per year per person and considering that 7 patients out of those diagnosed are treated curatively annually, the total cost would increase to nearly half a million Euros per annum. In view of this, one is bound to ask the question whether not treating patients with a 30% survival rate is justifiable, especially in view that surgical and oncologic treatment can result in severe disfigurement and poses great physical and psychological stress on patients. No studies about local decision-making with respect to HNSCC have been published. This study set out to explore this issue from the ethical point of view, taking into account a number of variables with respect to treatment and the patient factors. A pre-determined set of questions was formulated and these questions were tackled by ten medical professionals, nine of which had direct contact with HNSCC patients. Issues such as informed consent, old age, quality of life, social variables, autonomy, healthcare rationing, medico-legal problems and past experiences with patients have been identified and discussed with reference to the local situation. It was noted that the majority of interviewed professionals (70%), still emphasised the need to provide full treatment for low prognosis HNSCC.peer-reviewe

Non-Fundamental Expectations and Economic Fluctuations: Evidence from Professional Forecasts

It is theoretically possible that non-fundamental idiosyncratic shocks to agents’ rational expectations are a source of economic fluctuations. Studies using data on consumer and investor sentiment suggest that this is indeed a significant source of fluctuations. We present the results of a study that uses forecasts from professional forecasters to extract non-fundamental shocks to expectations. In contrast to previous studies, we show that non-fundamental expectations are not a significant source of output fluctuations.Non-fundamental expectations; Sunspots; Economic fluctuations; Survey of Professional Forecasters; Vector autoregressions

Cost as a Prohibitive Factor on Effectiveness of Informational Campaigns to Reduce Dental Sealant Disparities

To the Editor: The authors of the abstract “Reducing Dental Sealant Disparities in School-aged Children Through Better Targeting of Informational Campaigns” (1) state: The lack of an association between sealant prevalence and knowledge among low-income families may reflect higher levels of public provision of sealants to this group. This suggests that informational campaigns could increase demand for sealants in both income groups

Experimental studies of supporting wire disturbances in the near viscous wakes of slender supersonic bodies

Wires have often been used as a means of mechanically supporting a model so that its wake will be relatively free of support interference. Such support systems have many advantages over stings and are less costly than magnetic suspension systems. Investigations into the disturbances caused by these supporting wires have been carried out with the use of a two-dimensional flat plate and a wire supported slender cone. The tests were conducted in the University of Missouri-Rolla axisymmetric, supersonic wind tunnel at Mach 3.15, and at a Reynolds number of 2.14 X 10⁶ per inch. Schlieren photography, pitot and static pressure traverses in the near, viscous wake of an 8 degree half-angle wire supported cone were conducted in order to determine the effect of supporting wires on the flow. Additional related data is presented for a two-dimensional, sharp leading edge flat plate with an interference wire used to disturb the plate\u27s wake. Wires were shown to have no effect on the pitot pressures in the viscous wake. Data presented is compared to the previous work of others using supporting wires as a means of model support --Abstract, page ii

Grounded theory as a macromarketing methodology: critical insights from researching the marketing dynamics of Fairtrade Towns

This paper details and justifies Grounded Theory as a methodology for researching into significant and emerging macromarketing phenomena, through an exploration of its use to investigate the marketing dynamics of the Fairtrade Towns Movement. The paper describes the research ‘journey’ undertaken from the initial consideration of Fairtrade Towns as an under-researched and challenging topic, through to the final production of new theory rooted in the reality of the research context. The philosophy and systematic processes that underpin Grounded Theory are explained, along with examples of how the key processes of data collection and analysis were undertaken. The insights generated in this paper demonstrate Grounded Theory as a suitable, yet underused, research approach available to macromarketers. It is revealed as a methodology that can bring rigor and confidence to research into emerging macromarketing themes, and the paper concludes by considering its potential for application in key spheres for future research