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Spill
Kinds of Spill Selected AbstractsLENGTH-MASS AND TOTAL BODY LENGTH OF ADULT FEMALE SEA OTTERS IN PRINCE WILLIAM SOUND BEFORE AND AFTER THE EXXON VALDEZ OIL SPILLMARINE MAMMAL SCIENCE, Issue 4 2002Lisa Mignon Rotterman Abstract After the 1989 T/V Exxon Valdez oil spill (EVOS), the body condition of non-pregnant female sea otters (Enhydra lutris) ages 4 yr and older in the EVOS-affected region of western Prince William Sound, Alaska (WPWS), was significantly poorer than that of individuals captured in the same or adjacent habitat in WPWS approximately a decade earlier, and than that of individuals inhabiting unoiled habitat in eastern PWS (EPWS) between 1984 and 1990. However, the body condition of females of this age category captured in WPWS prior to EVOS was not significantly different from that of pre-and postspill EPWS females. The mean total body length (TBL) of non-pregnant females captured prespill in WPWS was significantly less than that of pre-and postspill EPWS and postspill WPWS females. Evidence from this and other studies suggests that the body condition of at least some classes of sea otters was negatively affected by one or more EVOS-related factors. [source] Early Socio-political and Environmental Consequences of the Prestige Oil Spill in GaliciaDISASTERS, Issue 3 2003J.D. García Pérez The controversial form in which the oil industry is run has once more caused a huge disaster , this one affecting the Galician coastal environment and economy. Oil-spill clean-up operations have been managed in Europe with some success but with considerable economic, environmental and social costs. The oil industry often avoids fully or even partially compensating those affected. The lack of both political will and political power has let the culprit (the oil industry) off the hook. This paper considers the spill of the Prestige to assess whether the balance of power between affected people and the oil industry can be changed. The paper examines the growing awareness of environmental issues among ordinary people in Spain, through the massive involvement of volunteers concerned with the damage done to the environment and to the livelihoods of fishing communities in Galicia. To understand these growing public concerns and the strength of opinion, the paper examines the details of the decisions taken by the central Spanish and local governments and the way these have informed the clean-up operations, the character of the oil companies involved and the feeling of impotence in the face of such disasters. The conclusion here is that the operations of the oil industry should be tightly regulated through EU legislation, and that this can come about as a result of organised political pressure from those affected by the oil spill, from the mass of volunteers, as well as from public opinion at large. [source] Incorporating Penalty Function to Reduce Spill in Stochastic Dynamic Programming Based Reservoir Operation of Hydropower PlantsIEEJ TRANSACTIONS ON ELECTRICAL AND ELECTRONIC ENGINEERING, Issue 5 2010Deependra Kumar Jha Non-member Abstract This paper proposes a framework that includes a penalty function incorporated stochastic dynamic programming (SDP) model in order to derive the operation policy of the reservoir of a hydropower plant, with an aim to reduce the amount of spill during operation of the reservoir. SDP models with various inflow process assumptions (independent and Markov-I) are developed and executed in order to derive the reservoir operation policies for the case study of a storage type hydropower plant located in Japan. The policy thus determined consists of target storage levels (end-of-period storage levels) for each combination of the beginning-of-period storage levels and the inflow states of the current period. A penalty function is incorporated in the classical SDP model with objective function that maximizes annual energy generation through operation of the reservoir. Due to the inclusion of the penalty function, operation policy of the reservoir changes in a way that ensures reduced spill. Simulations are carried out to identify reservoir storage guide curves based on the derived operation policies. Reservoir storage guide curves for different values of the coefficient of penalty function , are plotted for a study horizon of 64 years, and the corresponding average annual spill values are compared. It is observed that, with increasing values of ,, the average annual spill decreases; however, the simulated average annual energy value is marginally reduced. The average annual energy generation can be checked vis-ŕ-vis the average annual spill reduction, and the optimal value of , can be identified based on the cost functions associated with energy and spill. © 2010 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. [source] NIGERIA: Oil Spills IgnoredAFRICA RESEARCH BULLETIN: ECONOMIC, FINANCIAL AND TECHNICAL SERIES, Issue 6 2010Article first published online: 3 AUG 2010 No abstract is available for this article. [source] Eco-psychological profiling: an oil company exampleCORPORATE SOCIAL RESPONSIBILITY AND ENVIRONMENTAL MANAGEMENT, Issue 3 2004Tarja Ketola When organizational image is being challenged, use of psychological defences may become excessive. In this paper 18 defences that appeared in an oil company during an oil spill are studied. All defences except sublimation contributed to the deterioration of corporate image. Sublimation allowed the company to take responsibility. Other defences simply put off facing the truth. The selection of defences used during crises reveals organizations' true personalities. Twelve different organizational personality types are discussed. Use of certain defences leads to the development of a neurotic personality. The case company turned out to be normally and neurotically demanding, paranoid, narcissistic and attention seeking, and normally depressive. Organizations constantly using primitive defences are borderline personalities. Excessively defensive organizations may turn psychotic. The case company's reactions to the incident were psychologically revealing. Finding defences characteristic of the company allowed us to build its eco-psychological profile. Based on this case study an eco-psychological profiling model is proposed. Copyright © 2004 John Wiley & Sons, Ltd and ERP Environment. [source] Early Socio-political and Environmental Consequences of the Prestige Oil Spill in GaliciaDISASTERS, Issue 3 2003J.D. García Pérez The controversial form in which the oil industry is run has once more caused a huge disaster , this one affecting the Galician coastal environment and economy. Oil-spill clean-up operations have been managed in Europe with some success but with considerable economic, environmental and social costs. The oil industry often avoids fully or even partially compensating those affected. The lack of both political will and political power has let the culprit (the oil industry) off the hook. This paper considers the spill of the Prestige to assess whether the balance of power between affected people and the oil industry can be changed. The paper examines the growing awareness of environmental issues among ordinary people in Spain, through the massive involvement of volunteers concerned with the damage done to the environment and to the livelihoods of fishing communities in Galicia. To understand these growing public concerns and the strength of opinion, the paper examines the details of the decisions taken by the central Spanish and local governments and the way these have informed the clean-up operations, the character of the oil companies involved and the feeling of impotence in the face of such disasters. The conclusion here is that the operations of the oil industry should be tightly regulated through EU legislation, and that this can come about as a result of organised political pressure from those affected by the oil spill, from the mass of volunteers, as well as from public opinion at large. [source] Molecular detection of marine bacterial populations on beaches contaminated by the Nakhodka tanker oil-spill accidentENVIRONMENTAL MICROBIOLOGY, Issue 4 2001Yuki Kasai In January 1997, the tanker Nakhodka sank in the Japan Sea, and more than 5000 tons of heavy oil leaked. The released oil contaminated more than 500 km of the coastline, and some still remained even by June 1999. To investigate the long-term influence of the Nakhodka oil spill on marine bacterial populations, sea water and residual oil were sampled from the oil-contaminated zones 10, 18, 22 and 29 months after the accident, and the bacterial populations in these samples were analysed by denaturing gradient gel electrophoresis (DGGE) of PCR-amplified 16S rDNA fragments. The dominant DGGE bands were sequenced, and the sequences were compared with those in DNA sequence libraries. Most of the bacteria in the sea water samples were classified as the Cytophaga,Flavobacterium,Bacteroides phylum, ,- Proteobacteria or cyanobacteria. The bacteria detected in the oil paste samples were different from those detected in the sea water samples; they were types related to hydrocarbon degraders, exemplified by strains closely related to Sphingomonas subarctica and Alcanivorax borkumensis. The sizes of the major bacterial populations in the oil paste samples ranged from 3.4 × 105 to 1.6 × 106 bacteria per gram of oil paste, these low numbers explaining the slow rate of natural attenuation. [source] Analysis of micronuclei in blue mussels and fish from the Baltic and North SeasENVIRONMENTAL TOXICOLOGY, Issue 4 2004Janina Bar Abstract Micronuclei (MN) were analyzed in erythrocytes of flounder (Platichthys flesus) and wrasse (Symphodus melops) and in gill cells of blue mussels (Mytilus edulis). The organisms were collected from three study stations in the Baltic Sea and from seven stations in the North Sea (Karmsund area, Norway) 4 times. The statistically significant differences obtained were related to the season, sex of the fish, and sampling locality. Higher MN frequencies were found in fish and mussels collected from the most polluted study stations in the North Sea. The same tendency could be described in the Baltic Sea; however, it was masked by the recent oil spill from the Butinge oil terminal. Our results showing higher MN frequencies in presumably what were the most polluted study locations suggest that MN tests in fish and mussels may be used for the detection of genotoxic effects in a marine environment. The endpoint is well characterized and can be easily recognized, and the technique is convenient to use in field samplings following standard procedures and protocols. © 2004 Wiley Periodicals, Inc. Environ Toxicol 19: 365,371, 2004. [source] Genotoxicity related to transfer of oil spill pollutants from mussels to mammals via foodENVIRONMENTAL TOXICOLOGY, Issue 4 2004Sébastien Lemiere Abstract Heavy fuel oils containing high levels of polycyclic aromatic hydrocarbons (PAHs) were released into the marine environment after the Erika oil spill on the Atlantic coast. As highly condensed PAH pollutants can bioaccumulate in invertebrates, their transfer to vertebrates through the food chain was of concern. This study aimed to estimate potential genotoxic effects in rats fed for 2 or 4 weeks with the marine mussel Mytilus edulis contaminated by oil pollutants. Two levels of PAH contamination were studied, around 100 and 500 ,g of total PAHs/kg dry weight (d.w.) in mussels. Genotoxic damage in rats was investigated by single-cell gel electrophoresis (Comet assay) and micronucleus assays in liver, bone marrow, and peripheral blood. DNA damage was observed in the liver of rats fed with the most contaminated mussels (500 ,g PAHs/kg d.w.).DNA damage also was observed in the bone marrow but less than that in the liver. A small increase in micronuclei frequency was registered as well. This work underlines the bioavailability of pollutants in fuel-oil-contaminated mussels to consumers and the usefulness of the Comet assay as a sensitive tool in biomonitoring to analyze responses to PAH transfer in food. The occurrence of substituted PAHs and related compounds such as benzothiophenes in addition to nonsubstituted PAHs in fuel oils and mussels raised the question of whether they were implicated in the genotoxic effects registered in rats. © 2004 Wiley Periodicals, Inc. Environ Toxicol 19: 387,395, 2004. [source] Risk of weathered residual Exxon Valdez oil to pink salmon embryos in Prince William SoundENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 4 2007Ernest L. Brannon Abstract It has been hypothesized that pink salmon eggs incubating in intertidal streams transecting Prince William Sound (PWS) beaches oiled by the Exxon Valdez oil spill were exposed to lethal doses of dissolved hydrocarbons. Since polycyclic aromatic hydrocarbon (PAH) levels in the incubation gravel were too low to cause mortality, the allegation is that dissolved high-molecular-weight hydrocarbons (HPAH) leaching from oil deposits on the beach adjacent to the streams were the source of toxicity. To evaluate this hypothesis, we placed pink salmon eggs in PWS beach sediments containing residual oil from the Exxon Valdez oil spill and in control areas without oil. We quantified the hydrocarbon concentrations in the eggs after three weeks of incubation. Tissue PAH concentrations of eggs in oiled sediments were generally <100 ppb and similar to background levels on nonoiled beaches. Even eggs in direct contact with oil in the sediment resulted in tissue PAH loads well below the lethal threshold concentrations established in laboratory bioassays, and very low concentrations of HPAH compounds were present. These results indicate that petroleum hydrocarbons dissolved from oil deposits on intertidal beaches are not at concentrations that pose toxic risk to incubating pink salmon eggs. The evidence does not support the hypothesis that interstitial pore water in previously oiled beaches is highly toxic. [source] Alteration of normal cellular profiles in the scleractinian coral (Pocillopora damicornis) following laboratory exposure to fuel oilENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 12 2006Luc Rougée Abstract Petroleum contamination from oil spills is a continuing threat to our ocean's fragile ecosystems. Herein, we explored the effects of the water-soluble fraction of crude oil on a stony coral, Pocillopora damicornis (Linneaeus 1758). We developed methods for exposing corals to various concentrations of crude oil and for assessing the potential molecular responses of the corals. Corals were exposed to water-accommodated fraction solutions, and appropriate cellular biomarkers were quantified. When compared to the "healthy" control specimens, exposed corals exhibited shifts in biomarker concentrations that were indicative of a shift from homeostasis. Significant changes were seen in cytochrome P450 1-class, cytochrome P450 2-class, glutathione- S -transferase-pi, and cnidarian multixenobiotic resistance protein-1 biomarkers, which are involved the cellular response to, and manipulation and excretion of, toxic compounds, including polycyclic aromatic hydrocarbons. A shift in biomarkers necessary for porphyrin production (e.g., protoporphyrinogen oxidase IX and ferrochelatase) and porphyrin destruction (e.g., heme oxygenase-1 and invertebrate neuroglobin homologue) illustrates only one of the cellular protective mechanisms. The response to oxidative stress was evaluated through measurements of copper/zinc superoxide dismutase-1 and DNA glycosylase MutY homologue-1 concentrations. Likewise, changes in heat shock protein 70 and small heat shock proteins indicated an adjustment in the cellular production of proteins. Finally, the results of this laboratory study were nearly identical to what we observed previously among corals of a different species, Porites lobata, exposed to an oil spill in the field after the grounding of the Merchant Vessel Kyowa Violet. [source] Predicting single and mixture toxicity of petrogenic polycyclic aromatic hydrocarbons to the copepod Oithona davisaeENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 11 2005Carlos Barata Abstract In the present study, the acute toxicity of 10 polycyclic aromatic hydrocarbons (PAH) associated with the Prestige fuel oil spill (Spain, 2002) were evaluated, either as single substances or in mixtures, in adults of the copepod Oithona davisae. All but dimethylphenanthrene had negative effects on O. davisae survival at concentrations below their water solubility, with 48-h median lethal concentrations for naphthalene and pyrene of 56.1 and 0.8 ,mol/L, respectively, making these the least and most toxic compounds. Polycyclic aromatic hydrocarbons had narcotic effects on copepods, as evidenced by the lack of motility at lower concentrations than those causing death. Naphthalene showed the greatest narcotic effects, and phenanthrene showed minor effects. Acute toxicity of the tested PAHs was inversely related (r2 = 0.9) with their octanol,water partition coefficient, thereby confirming the validity of the baseline quantitative structure,activity regression models for predicting the toxicity of PAH compounds in copepod species. When supplied in mixtures, the toxic effect of PAHs was additive. These results indicate that the many PAHs in an oil spill can be considered unambiguous baseline toxicants (class 1) acting additively as nonpolar narcotics in copepods; hence, their individual and combined toxicity can be predicted using their octanol,water partition coefficient. [source] The Prestige oil spill.ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 9 2005Abstract In vitro biodegradation of the Prestige heavy fuel oil has been carried out using two microbial consortia obtained by enrichment in different substrates to simulate its environmental fate and potential utility for bioremediation. Different conditions, such as incubation time (i.e., 20 or 40 d), oil weathering, and addition of an oleophilic fertilizer (S200), were evaluated. Weathering slowed down the degradation of the fuel oil, probably because of the loss of lower and more labile components, but the addition of S200 enhanced significantly the extension of the biodegradation. n -Alkanes, alkylcyclohexanes, alkylbenzenes, and the two- to three-ring polycyclic aromatic hydrocarbons (PAHs) were degraded in 20 or 40 d of incubation of the original oil, whereas the biodegradation efficiency decreased for higher PAHs and with the increase of alkylation. Molecular markers were degraded according to the following sequence: Acyclic isoprenoids < diasteranes < C27 -steranes < ,,-steranes < homohopanes < monoaromatic steranes < triaromatic steranes. Isomeric selectivity was observed within the C1 - and C2 -phenanthrenes, dibenzothiophenes, pyrenes, and chrysenes, providing source and weathering indices for the characterization of the heavy oil spill. Acyclic isoprenoids, C27 -steranes, C1 - and C2 -naphthalenes, phenanthrenes, and dibenzothiophenes were degraded completely when S200 was used. The ratios of the C2 - and C3 -alkyl homologues of fluoranthene/pyrene and chrysene/benzo[a]anthracene are proposed as source ratios in moderately degraded oils. The 4-methylpyrene and 3-methylchrysene were refractory enough to serve as conserved internal markers in assessing the degradation of the aromatic fraction in a manner similar to that of hopane, as used for the aliphatic fraction. [source] The influence of pH and salinity on the toxicity of heavy metals in sediment to the estuarine clam Ruditapes philippinarum,ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 5 2004Inmaculada Riba Abstract An approach is presented for determining the influence of two key variables, pH and salinity(S), on the toxicity of four common heavy metals bound to sediments in estuaries. Two samples of environmental sediment taken from two estuaries in southern Spain (the Huelva estuary and the Guadalquivir River estuary), together with a dilution of toxic mud from the Aznalcóllar (Spain) mining spill (April 1998) were used to determine their toxicity at different values of pH (6.5, 7.5, and 8.5) and salinity (10, 20, and 30) on the estuarine clam Ruditapes philippinarum. Two different endpoints, sublethal, indicated by clam reburial (median effective burial time [ET50]), and relative mortality (median lethal concentration [LC50]), were used to quantify the toxicity associated with the heavy metals. Neither salinity nor pH was found to influence the toxic responses measured by the behavioral endpoint (ET50). However, a strong effect on the LC50 related to pH and salinity was detected, with the toxicity of the heavy metals being increased at low values of both variables (pH = 6.5 and S = 10). The mechanism of heavy metals uptake through water may explain this influence of pH and salinity on the lethal toxicity detected. The results show differences in the toxicity of these heavy metals bound to sediments depending on whether the origin of metal contamination is chronic or acute. [source] Oxidative stress biomarkers in bivalves transplanted to the Guadalquivir estuary after Aznalcóllar spillENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 1 2003Antonio Romero-Ruiz Abstract Biological effects of metals were studied in clams (Scrobicularia plana) transplanted to Guadalquivir estuary (Spain) at several times after the spill of toxic metals from Aznalcóllar pyrite mine (southwest Spain) (April 1998) using biochemical biomarkers responsive to reactive oxygen species. Significant As, Cd, Fe, Mn, Ni, and Pb uptake was found in clams living for seven months at the estuary (from July 1999). Increased activity of antioxidant (catalase, glucose-6-phosphate, and 6-phosphogluconate dehydrogenase) and glutathione-related (glutathione reductase and glyoxalase I and II) enzymes was also found after short exposures; the levels of malondialdehyde and metallothionein increased also, particularly with long exposures. Clams living four weeks at the estuary (from March 2000) but not at a reference site also accumulated metals. The higher malondialdehyde and lower reduced-glutathione levels and the more oxidized glutathione status confirmed the oxidative stress of clams living at the estuary, while no marked increase of antioxidant activities was found this time. Lower metal availability along the second transplant could explain the limited responses in this shorter experiment. Although the status of Guadalquivir estuary has recovered since Aznalcóllar spill, continuous monitoring is needed to confirm its progress and to be alert to possible deterioration after heavy rains. [source] Pollution of carbonate soils in a Mediterranean climate due to a tailings spillEUROPEAN JOURNAL OF SOIL SCIENCE, Issue 2 2002M. Simón Summary The retention walls in a pond containing the residues from the pyrite mine of Aznalcóllar (southern Spain) broke open on 25 April 1998, spilling approximately 6 × 106 m3 of polluted water and toxic tailings, which affected some 55 km2. Drying and aeration of the tailings resulted in oxidation, forming an acidic solution with high pollutant contents, the effects of which were studied in a calcareous soil. The infiltration of this solution markedly affected only the first 12 mm of the soil, where strong acidification caused the weathering of the carbonates, and where the fine mineral particles were hydrolysed. The SO42, ions in the acidic solution precipitated almost entirely at this depth, forming gypsum, hydroxysulphates and complex sulphates. The Fe3+ ions also precipitated there, mainly in amorphous or poorly crystallized forms, adsorbing to As, Sb, Tl and Pb dissolved in the acidic solution. The Al3+ ions, though partly precipitating in the acidic layer, accumulated mostly where the soil pH exceeded 5.5 (12,14 mm in depth). They did so primarily as amorphous or poorly crystallized forms, adsorbing to Cu dissolved in the acidic solution. The Zn2+ and Cd2+ ions accumulated mainly at pH > 7.0 (19,21 mm in depth), being adsorbed chiefly by clay mineral. After 15 months, only the first 20 mm of the soil were acidified by the oxidation of the tailings and most of the pollutants did not penetrate deeper than 100 mm. Consequently, the speed of the cleanup of the toxic spill is not as important as a thorough removal of tailings together with the upper 10 cm of the soil. [source] An electromagnetic modelling tool for the detection of hydrocarbons in the subsoilGEOPHYSICAL PROSPECTING, Issue 2 2000Carcione Electromagnetic geophysical methods, such as ground-penetrating radar (GPR), have proved to be optimal tools for detecting and mapping near-surface contaminants. GPR has the capability of mapping the location of hydrocarbon pools on the basis of contrasts in the effective permittivity and conductivity of the subsoil. At radar frequencies (50 MHz to 1 GHz), hydrocarbons have a relative permittivity ranging from 2 to 30, compared with a permittivity for water of 80. Moreover, their conductivity ranges from zero to 10 mS/m, against values of 200 mS/m and more for salt water. These differences indicate that water/hydrocarbon interfaces in a porous medium are electromagnetically ,visible'. In order to quantify the hydrocarbon saturation we developed a model for the electromagnetic properties of a subsoil composed of sand and clay/silt, and partially saturated with air, water and hydrocarbon. A self-similar theory is used for the sandy component and a transversely isotropic constitutive equation for the shaly component, which is assumed to possess a laminated structure. The model is first verified with experimental data and then used to obtain the properties of soils partially saturated with methanol and aviation gasoline. Finally, a GPR forward-modelling method computes the radargrams of a typical hydrocarbon spill, illustrating the sensitivity of the technique to the type of pore-fluid. The model and the simulation algorithm provide an interpretation methodology to distinguish different pore-fluids and to quantify their degree of saturation. [source] Incorporating Penalty Function to Reduce Spill in Stochastic Dynamic Programming Based Reservoir Operation of Hydropower PlantsIEEJ TRANSACTIONS ON ELECTRICAL AND ELECTRONIC ENGINEERING, Issue 5 2010Deependra Kumar Jha Non-member Abstract This paper proposes a framework that includes a penalty function incorporated stochastic dynamic programming (SDP) model in order to derive the operation policy of the reservoir of a hydropower plant, with an aim to reduce the amount of spill during operation of the reservoir. SDP models with various inflow process assumptions (independent and Markov-I) are developed and executed in order to derive the reservoir operation policies for the case study of a storage type hydropower plant located in Japan. The policy thus determined consists of target storage levels (end-of-period storage levels) for each combination of the beginning-of-period storage levels and the inflow states of the current period. A penalty function is incorporated in the classical SDP model with objective function that maximizes annual energy generation through operation of the reservoir. Due to the inclusion of the penalty function, operation policy of the reservoir changes in a way that ensures reduced spill. Simulations are carried out to identify reservoir storage guide curves based on the derived operation policies. Reservoir storage guide curves for different values of the coefficient of penalty function , are plotted for a study horizon of 64 years, and the corresponding average annual spill values are compared. It is observed that, with increasing values of ,, the average annual spill decreases; however, the simulated average annual energy value is marginally reduced. The average annual energy generation can be checked vis-ŕ-vis the average annual spill reduction, and the optimal value of , can be identified based on the cost functions associated with energy and spill. © 2010 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. [source] Heterogeneity and cross section dependence in panel data models: theory and applications introductionJOURNAL OF APPLIED ECONOMETRICS, Issue 2 2007Badi H. Baltagi The papers included in this special issue are primarily concerned with the problem of cross section dependence and heterogeneity in the analysis of panel data models and their relevance in applied econometric research. Cross section dependence can arise due to spatial or spill over effects, or could be due to unobserved (or unobservable) common factors. Much of the recent research on non-stationary panel data have focussed on this problem. It was clear that the first generation panel unit root and cointegration tests developed in the 1990's, which assumed cross-sectional independence, are inadequate and could lead to significant size distortions in the presence of neglected cross-section dependence. Second generation panel unit root and cointegration tests that take account of possible cross-section dependence in the data have been developed, see the recent surveys by Choi (2006) and Breitung and Pesaran (2007). The papers by Baltagi, Bresson and Pirotte, Choi and Chue, Kapetanios, and Pesaran in this special issue are further contributions to this literature. The papers by Fachin, and Moon and Perron are empirical studies in this area. Controlling for heterogeneity has also been an important concern for empirical researchers with panel data methods promising better handle on heterogeneity than cross-section data methods. The papers by Hsiao, Shen, Wang and Weeks, Pedroni and Serlenga and Shin are empirical contributions to this area. Copyright © 2007 John Wiley & Sons, Ltd. [source] Low temperature bioremediation of oil-contaminated soil using biostimulation and bioaugmentation with a Pseudomonas sp. from maritime AntarcticaJOURNAL OF APPLIED MICROBIOLOGY, Issue 4 2005B. Stallwood Abstract Aims:, To identify native Antarctic bacteria capable of oil degradation at low temperatures. Methods and Results:, Oil contaminated and pristine soils from Signy Island (South Orkney Islands, Antarctica) were examined for bacteria capable of oil degradation at low temperatures. Of the 300 isolates cultured, Pseudomonas strain ST41 grew on the widest range of hydrocarbons at 4°C. ST41 was used in microcosm studies of low temperature bioremediation of oil-contaminated soils. Microcosm experiments showed that at 4°C the levels of oil degradation increased, relative to the controls, with (i) the addition of ST41 to the existing soil microbial population (bioaugmentation), (ii) the addition of nutrients (biostimulation) and to the greatest extent with (iii) a combination of both treatments (bioaugmentation and biostimulation). Addition of water to oil contaminated soil (hydration) also enhanced oil degradation, although less than the other treatments. Analysis of the dominant species in the microcosms after 12 weeks, using temporal temperature gradient gel electrophoresis, showed Pseudomonas species to be the dominant soil bacteria in both bioaugmented and biostimulated microcosms. Conclusions:, Addition of water and nutrients may enhance oil degradation through the biostimulation of indigenous oil-degrading microbial populations within the soil. However, bioaugmentation with Antarctic bacteria capable of efficient low temperature hydrocarbon degradation may enhance the rate of bioremediation if applied soon after the spill. Significance and Impact of the Study:, In the future, native soil bacteria could be of use in bioremediation technologies in Antarctica. [source] Temporary Liaisons: The Commitment of ,Temps' Towards Their Agencies*JOURNAL OF MANAGEMENT STUDIES, Issue 3 2005Gerla Van Breugel abstract The majority of research on organizational commitment has focused on commitment in traditional, ongoing and open-ended relationships. The commitment of employees in non-standard work arrangements such as temporary employment has been subject to much less theoretical and empirical investigation. In this study, we examine the affective and continuance commitment of temporary workers towards their agency and its determinants. We distinguish two groups of determinants: the process by which the temporary worker chose a particular agency and the support provided by the agency. The findings can be summarized as follows: (1) affective commitment among temps is generally higher than their continuance commitment; (2) having more alternative agencies to choose from (i.e., volition) does not enhance the commitment of temporary workers; (3) a public choice for a particular agency raises both types of commitment, whereas the perceived agency dependence created by the choice increases continuance, but not affective commitment; and (4) both types of commitment are positively influenced by agency supportiveness, reflected in the way the agency deals with problems, the career support it provides, and the way it keeps in close contact with its temporary workers. Finally, the results suggest that factors raising affective commitment may ,spill over' to increase continuance commitment. [source] The confounding role of personality and trait affectivity in the relationship between job and life satisfactionJOURNAL OF ORGANIZATIONAL BEHAVIOR, Issue 7 2002Daniel Heller Previous research has demonstrated a strong positive relationship between job and life satisfaction. Traditionally, this relationship has been explained in terms of a spillover model, wherein job experiences spill over onto life, and vice versa. This study directly tests a different explanation for this relationship: personality traits that influence both job and life satisfaction. In a longitudinal test with multisource data, three typologies, which were shown by past research to be linked to both job and life satisfaction, were examined: Big Five, positive and negative affectivity, and core self-evaluations. One hundred and fifty-three university employees working in a diverse set of occupations were surveyed twice, with a six month time interval; the first survey also included a second questionnaire to be completed by a ,significant other.' Analyses of concurrent and prospective zero-order and partial correlations, as well as structural equation modeling, supported the hypothesized confounding role of all three typologies, especially core self-evaluations. Though controlling for personality reduced the magnitude of the job,life satisfaction relationship, it did not entirely eliminate it. Overall, the results suggest the presence of both dispositional and environmental factors in job and life satisfaction. Finally, implications for organizational practice and theory development are discussed. Copyright © 2002 John Wiley & Sons, Ltd. [source] Coping with technological disaster: An application of the conservation of resources model to the Exxon Valdez oil spillJOURNAL OF TRAUMATIC STRESS, Issue 1 2000Catalina M. Arata Abstract One hundred twenty-five commercial fishers in Cordova, Alaska, completed a mailed survey regarding current mental health functioning 6 years after the Exxon Valdez oil spill. Economic and social impacts of the oil spill and coping and psychological functioning (modified Coping Strategies Scales, Symptom Checklist 90-R) were measured. Multiple regression was used to test the utility of the Conservation of Resources stress model for explaining observed psychological symptoms. Current symptoms of depression, anxiety, and Posttraumatic Stress Disorder were associated with conditions resource loss and avoidant coping strategies. The Conservation of Resources model provided a framework for explaining psychological impacts of the oil spill. Future research is needed to identify factors related to recovery. [source] LENGTH-MASS AND TOTAL BODY LENGTH OF ADULT FEMALE SEA OTTERS IN PRINCE WILLIAM SOUND BEFORE AND AFTER THE EXXON VALDEZ OIL SPILLMARINE MAMMAL SCIENCE, Issue 4 2002Lisa Mignon Rotterman Abstract After the 1989 T/V Exxon Valdez oil spill (EVOS), the body condition of non-pregnant female sea otters (Enhydra lutris) ages 4 yr and older in the EVOS-affected region of western Prince William Sound, Alaska (WPWS), was significantly poorer than that of individuals captured in the same or adjacent habitat in WPWS approximately a decade earlier, and than that of individuals inhabiting unoiled habitat in eastern PWS (EPWS) between 1984 and 1990. However, the body condition of females of this age category captured in WPWS prior to EVOS was not significantly different from that of pre-and postspill EPWS females. The mean total body length (TBL) of non-pregnant females captured prespill in WPWS was significantly less than that of pre-and postspill EPWS and postspill WPWS females. Evidence from this and other studies suggests that the body condition of at least some classes of sea otters was negatively affected by one or more EVOS-related factors. [source] Bioremediation of marine oil spills: when and when not , the Exxon Valdez experienceMICROBIAL BIOTECHNOLOGY, Issue 2 2009Ronald Atlas Summary In this article we consider what we have learned from the Exxon Valdez oil spill (EVOS) in terms of when bioremediation should be considered and what it can accomplish. We present data on the state of oiling of Prince William Sound shorelines 18 years after the spill, including the concentration and composition of subsurface oil residues (SSOR) sampled by systematic shoreline surveys conducted between 2002 and 2007. Over this period, 346 sediment samples were analysed by GC-MS and extents of hydrocarbon depletion were quantified. In 2007 alone, 744 sediment samples were collected and extracted, and 222 were analysed. Most sediment samples from sites that were heavily oiled by the spill and physically cleaned and bioremediated between 1989 and 1991 show no remaining SSOR. Where SSOR does remain, it is for the most part highly weathered, with 82% of 2007 samples indicating depletion of total polycyclic aromatic hydrocarbon (Total PAH) of > 70% relative to EVOS oil. This SSOR is sequestered in patchy deposits under boulder/cobble armour, generally in the mid-to-upper intertidal zone. The relatively high nutrient concentrations measured at these sites, the patchy distribution and the weathering state of the SSOR suggest that it is in a form and location where bioremediation likely would be ineffective at increasing the rate of hydrocarbon removal. [source] Which traits promote persistence of feral GM crops?OIKOS, Issue 1 2005Part 2: implications of metapopulation structure Transgenes may spread from crops into the environment via the establishment of feral populations, often initiated by seed spill from transport lorries or farm machinery. Locally, such populations are often subject to large environmental variability and usually do not persist longer than a few years. Because secondary feral populations may arise from seed dispersal to adjacent sites, the dynamics of such populations should be studied in a metapopulation context. We study a structured metapopulation model with local dispersal, mimicking a string of roadside subpopulations of a feral crop. Population growth is assumed to be subject to local disturbances, introducing spatially random environmental stochasticity. Our aim is to understand the role of dispersal and environmental variability in the dynamics of such ephemeral populations. We determine the effect of dispersal on the extinction boundary and on the distribution of persistence times, and investigate the influence of spatially correlated disturbances as opposed to spatially random disturbances. We find that, given spatially random disturbances, dispersal slows down the decline of the metapopulation and results in the occurrence of long-lasting local populations which remain more or less static in space. We identify which life history traits, if changed by genetic modification, have the largest impact on the population growth rate and persistence times. For oilseed rape, these are seed bank survival and dormancy. Combining our findings with literature data on transgene-induced life history changes, we predict that persistence is promoted by transgenes for oil-modifications (high stearate or high laurate) and, possibly, for insect resistence (Bt). Transgenic tolerance to glufosinate herbicide is predicted to reduce persistence. [source] Pilot Scale Demonstration of the Electrochemical Peroxidation Process at a Petroleum Spill SiteREMEDIATION, Issue 1 2000William P. Healy In a pilot test experiment involving approximately 200,000 gallons of groundwater, Electrochemical Peroxidation (ECP) was used to degrade aqueous phase volatile organic compounds (VOCs) including benzene, toluene, ethylbenzene, and xylene (BTEX) compounds and methyl tertbutyl ether (MTBE) from a petroleum spill. ECP involves a form of the Fenton's Reagent reaction, which uses electrochemically generated iron and dilute hydrogen peroxide (<30 mg/L) to break down organic molecules through oxidation to carbon dioxide and water. This article discusses a pilot scale demonstration of the ECP technology and its application to aqueous phase organic contaminants. The remedial approach used at the pilot test site involves three phases: (1) ex-situ chemical oxidation, (2) in-situ oxidation by reinjection of treated effluent near the plume origin, and (3) reestablishment of aerobic biodegradation as the residual hydrogen peroxide discharged to a series of upgradient wells degrades to oxygen. Analytical results of the pilot demonstration indicate that the ex-situ chemical oxidation reduced total BTEX concentrations in groundwater from over 1,000 ppb to undetectable concentrations (<1 ppb). © 2000 John Wiley & Sons, Inc. [source] Animal decisions and conservation: the recolonization of a severely polluted river by the Eurasian otterANIMAL CONSERVATION, Issue 5 2009M. Delibes Abstract Animals make decisions relying on environmental cues associated to high survival or breeding success along their evolutionary history. However, because of rapid anthropogenic changes in the environment, they may lack useful cues, making bad decisions with potential consequences for individuals and populations. Contaminants are difficult or impossible to detect for animals, so polluted habitats could be used in spite of their dangerous effects. The Eurasian otter Lutra lutra reoccupied the Guadiamar River (SW Spain) <1 year after a toxic spill that killed the fauna living in it. The levels of heavy metals and arsenic (As) in the river trophic web at that moment were probably harmful for otters. To investigate this, we determined the amount of several heavy metals including copper, cadmium, zinc (Zn) and lead (Pb) and metalloids such as As in otter faeces and estimated the exposure of otters to these elements as average ingestion. Concentrations of Zn, Pb and As were statistically higher in faeces collected along the Guadiamar River than in those collected along the Guadalete River (reference area). An ,average otter' in the Guadiamar River would consume 3,4 mg of Pb and more than 5 mg of As daily. Such doses must be hazardous for the species and challenge the usual assertion that otter presence is a good indicator of river quality. [source] Cerebral gunshot wounds: a score based on three clinical parameters to predict the risk of early mortalityANZ JOURNAL OF SURGERY, Issue 11 2009Michael Stoffel Abstract Background:, To provide a score to predict the risk of early mortality after single craniocerebral gunshot wound (GSW) based on three clinical parameters. Methods:, All patients admitted to Baragwanath Hospital, Johannesburg, South Africa, between October 2000 and May 2005 for an isolated single craniocerebral GSW were retrospectively evaluated for the documentation of (i) blood pressure (BP) on admission; (ii) inspection of the bullet entry and exit site; and (iii) initial consciousness (n= 214). Results:, Conscious GSW victims had an early mortality risk of 8.3%, unconscious patients a more than fourfold higher risk (39.2%). Patients with a systolic BP between 100 and 199 mm Hg had an 18.2% risk of mortality. Hypotension (<100 mm Hg) doubled this risk (37.7%) and severe hypertension (,200 mm Hg) was associated with an even higher mortality rate of 57.1%. Patients without brain spilling out of the wound (,non-oozer') exhibited a mortality of 19.7%, whereas it was twice as high (43.3%) in patients with brain spill (,oozer'). By logistic regression, a prognostic index for each variant of the evaluated parameters could be established: non-oozer:0, oozer:1, conscious:0, unconscious:2, 100 ,RRsys < 200 mm Hg:0, RRsys < 100 mm Hg:1, RRsys, 200 mm Hg:2. This resulted in a score (0,5) by which the individual risk of early mortality after GSW can be anticipated. Conclusions:, Three immediately obtainable clinical parameters were evaluated and a score for predicting the risk of early mortality after a single craniocerebral GSW was established. [source] Determination of arsenic species in a freshwater crustacean Procambarus clarkiiAPPLIED ORGANOMETALLIC CHEMISTRY, Issue 3 2002V. Devesa Abstract The arsenic species present in samples of the crayfish Procambarus clarkii caught in the area affected by the toxic mine-tailing spill at Aznalcóllar (Seville, Southern Spain) were analyzed. The total arsenic contents ranged between 1.2 and 8.5,µg g,1 dry mass (DM). With regard to the different species of arsenic, the highest concentrations were for inorganic arsenic (0.34,5.4,µg g,1 DM), whereas arsenobetaine, unlike the situation found in marine fish products, was not the major arsenic species (0.16,±,0.09,µg g,1 DM). Smaller concentrations were found of arsenosugars 1a (0.18,±,0.11,µg g,1 DM), 1b (0.077,±,0.049,µg g,1 DM), 1c (0.080,±,0.089,µg g,1 DM), and 1d (0.14,±,0.13,µg g,1 DM). The presence of two unknown arsenic species was revealed (U1: 0.058,±,0.058,µg g,1 DM; U2: 0.12,±,0.12,µg g,1 DM). No significant differences were seen with respect to the total arsenic contents between the sexes. However, significant differences in the total arsenic contents were revealed between the area affected by the spill and the area not affected, the contents being greater in the affected area. Copyright © 2002 John Wiley & Sons, Ltd. [source] | |||||||||||||||||||||||||||||||