Interdisciplinary studies on the technical and economic feasibility of deep underground coal gasification with CO<Subscript>2</Subscript> storage in bulgaria

This paper presents the outcome of a feasibility study on underground coal gasification (UCG) combined with direct carbon dioxide (CO₂) capture and storage (CCS) at a selected site in Bulgaria with deep coal seams (>1,200 m). A series of state-of-the-art geological, geo-mechanical, hydrogeological and computational models supported by experimental tests and techno-economical assessments have been developed for the evaluation of UCG-CCS schemes. Research efforts have been focused on the development of site selection requirements for UCG-CCS, estimation of CO₂ storage volumes, review of the practical engineering requirements for developing a commercial UCG-CCS storage site, consideration of drilling and completion issues, and assessments of economic feasibility and environmental impacts of the scheme. In addition, the risks of subsidence and groundwater contamination have been assessed in order to pave the way for a full-scale trial and commercial applications. The current research confirms that cleaner and cheaper energy with reduced emissions can be achieved and the economics are competitive in the future European energy market. However the current research has established that rigorous design and monitor schemes are essential for productivity and safety and the minimisation of the potential environmental impacts. A platform has been established serving to inform policy-makers and aiding strategies devised to alleviate local and global impacts on climate change, while ensuring that energy resources are optimally harnessed.     

Brownfields Update: The Reform of the Brownfields Economic Redevelopment Initiative

This journal first reported on the U.S. EPA's Brownfields Initiative in the summer 1995 edition of Remediation. At that time, the initiative was only about 15 months old, most of the state programs were in proposal stages, and little federal legislation addressing brownfields had been proposed. Today, brownfields has become such a common term that almost every environmental professional is familiar with it. The EPA has placed extremely high priority on the Brownfields Initiative and it has become a politically hot issue. This article provides an update on the current status of EPA's Brownfields program and also discusses recent legislation proposed by Congress to promote brownfields redevelopment. © 2001 John Wiley & Sons, Inc.     

Metabolic rate throughout the annual cycle reveals the demands of an Arctic existence in great cormorants

Aquatic endotherms living in polar regions are faced with a multitude of challenges, including low air and water temperatures and low illumination, especially in winter. Like other endotherms from cold environments, Great Cormorants (Phalacrocorax carbo) living in Arctic waters were hypothesized to respond to these challenges through a combination of high daily rate of energy expenditure (DEE) and high food requirements, which are met by a high rate of catch per unit effort (CPUE). CPUE has previously been shown in Great Cormorants to be the highest of any diving bird. In the present study, we tested this hypothesis by making the first measurements of DEE and foraging activity of Arctic-dwelling Great Cormorants throughout the annual cycle. We demonstrate that, in fact, Great Cormorants have surprisingly low rates of DEE. This low DEE is attributed primarily to very low levels of foraging activity, particularly during winter, when the cormorants spent only 2% of their day submerged. Such a low level of foraging activity can only be sustained through consistently high foraging performance. We demonstrate that Great Cormorants have one of the highest recorded CPUEs for a diving predator; 18.6 g per minute submerged (95% prediction interval 13.0-24.2 g/min) during winter. Temporal variation in CPUE was investigated, and highest CPUE was associated with long days and shallow diving depths. The effect of day length is attributed to seasonal variation in prey abundance. Shallow diving leads to high CPUE because less time is spent swimming between the surface and the benthic zone where foraging occurs. Our study demonstrates the importance of obtaining accurate measurements of physiology and behavior from free-living animals when attempting to understand their ecology.     

Fumarylacetoacetase activity in cultured and non-cultured chorionic villus cells,and assay in two high-risk pregnancies

We describe further development of the fumarylacetoacetase (FAA) assay for the prenatal diagnosis of tyrosinaemia type 1 using chorionic villus sampling (CVS). We have established a reference range for FAA activity in cultured villus cells and have confirmed previously reported data on the FAA activity in uncultured chorionic villus cells. This should allow confirmation of results using CVS, without the need for further invasive procedures. We report the FAA enzyme stability at −70°C, +4°C, and at room temperature, and we have shown no obvious difference in enzyme activity with gestational age. We have analysed cultured and non-cultured CVS activity of FAA in two pregnancies at risk of tyrosinaemia type 1. In both, the fetus was designated unaffected, and these results were confirmed postnatally.     

Fibrinopeptide a increases after Chorionic villus sampling

Fibrinopeptide levels were measured in 20 women during transcervical chorionic villus sampling (CVS). Fibrinopeptide A, a sensitive indicator of fibrinogen cleavage by thrombin, significantly increased in five subjects, whereas there was no change in Bβ peptide, an indicator of fibrinolysis. The data suggest that modest fibrin formation, uncompensated by fibrinolysis, may be induced in some women by CVS.     

Prenatal exclusion of the hhh syndrome

Prenatal diagnosis of the hyperornithinaemia, hyperammonaemia, and homocitrullinuria syndrome is described by the analysis of ornithine incorporation in second-trimester cultured amniotic fluid cells. An unaffected fetus was predicted and confirmed in the newborn child. This is the third reported prenatal diagnosis for this disorder and the second predicting an unaffected fetus.     

Kin recognition and cannibalistic behaviours by adult male fathead minnows (<Emphasis Type="Italic">Pimephales promelas</Emphasis>)

Parental care is an energetically demanding activity that ensures genes are efficiently passed from one generation to the next. According to evolutionary theory, the greatest energetic investment should be directed towards offspring that are most closely related to the parent. Male fathead minnows, Pimephales promelas, provide this parental investment to developing embryos but not newly hatched larvae. Therefore, selection should favour recognition of embryonic kin to ensure energetic expenditure is optimally invested. In this study, adult male fathead minnows were tested using behavioural assays, with egg cannibalism as an endpoint, to determine whether adult males could discriminate between related and unrelated embryos. Egg cannibalism was highest when adult male fathead minnows were presented with unrelated eggs and lowest when presented with eggs fertilized by the test subject (related eggs). The degree of cannibalism was also a function of breeding status. Unrelated males in breeding condition showed an intermediate response between the low cannibalism demonstrated by related males and the high cannibalism demonstrated by unrelated males in a nonbreeding condition. These results suggest that although male fathead minnows can discriminate between unrelated and related embryos, at least some component of parental investment is a simple function of breeding status.     

Tidal salt marsh sediment in California, USA. Part 1: occurrence and sources of organic contaminants

Surface sediment samples (0-5 cm) from five tidal marshes along the coast of California, USA were analyzed for organic pollutants to investigate their relationship to land use, current distribution within marshes, and possible sources. Among the study areas, Stege Marsh, located in San Francisco Bay, was the most contaminated. Compared to San Francisco Bay, Stege Marsh had much higher levels of organic contaminants such as PCBs (polychlorinated biphenyls), DDTs, and chlordanes. At reference marshes (Tom's Point and Walker Creek in Tomales Bay), organic contaminants in sediments were very low. While PAHs (polycyclic aromatic hydrocarbons) were found at all of the study areas (22-13,600 ng g(-1)), measurable concentrations of PCBs were found only in the sediments from Stege Marsh (80-9,940 ng g(-1)). Combustion related (pyrogenic) high molecular weight PAHs were dominant in sediments from Stege and Carpinteria Marshes, while in sediments from Tom's Point and Walker Creek petroleum related (petrogenic) low molecular weight PAHs and alkyl-substituted PAHs were much more abundant than pyrogenic PAHs. PCB congener patterns in all of the Stege Marsh samples were the same and revealed that Aroclor 1248 was a predominant source. In all marshes, the sum of DDE and DDD accounted for more than 90% of total DDTs, indicating that DDT has degraded significantly. The ratios of p,p'-DDE to p,p'-DDD in sediments from Stege Marsh provide evidence of possible previous use of technical DDD. Chlordane ratios indicated that chlordanes have degraded slightly. Bis(2-ethylhexyl)phthalate (280-32,000 ng g(-1)) was the most abundant phthalate. The data indicates that Stege Marsh may be a source of contaminants that continue to be discharged into San Francisco Bay.     

Oxidative damage in gill of Mytilus edulis from Merseyside, UK, and reversibility after depuration

Mussels were collected from the urban/industrialized site of New Brighton, Merseyside and the relatively non-industrial site of Llandudno, North Wales. All mussels were identified as Mytilus edulis by PCR amplification of Mefp1. DNA single strand breaks and 8-oxo-7,8-dihydro-2'-deoxyguanosine were measured in gill within 24h of collection, using the COMET assay, both with and without formamidopyrimidine glycosylase. Gill lipid peroxidation was also measured within 24h. No difference between sites was found for frank SSB and malonaldehyde levels, however 8-oxo-dG and 4-hydroxynonenal were significantly greater in New Brighton mussels compared to Llandudno mussels. After 1-month laboratory maintenance, lipid peroxidation and 8-oxo-dG levels were lower. In contrast, frank SSB were higher. This could reflect enhanced DNA repair excision, though we cannot exclude the possibility of other non-oxidative DNA damage. The results suggest that laboratory maintenance allows recovery from environmentally induced oxidative damage, which was more extensive at Merseyside.