bluuebunny/crossref_metadata_2025_split huggingface dataset:
Environmental fate of the antifouling compound zinc pyrithione in seawater
Authors: Grunnet Katja S. , Dahllof Ingela 
Published: November 2005

Abstract
To perform a thorough risk assessment of the new antifouling compound zinc pyrithione (ZnPT2), additional information regarding the fate of the compound is needed. The present study examined the recovery and transchelation of ZnPT2 in controlled laboratory experiments, photodegradation experiments, and a fate study in a large-scale field experiment. Chemical analyses were performed using a newly developed method for simultaneous analyses of ZnPT2 and copper pyrithione (CuPT2). Furthermore, two antifouling paints containing ZnPT2 were examined for the fate of leaching biocide. Naturally occurring ligands and metals in seawater influence the stability of ZnPT2. The presence of free Cu2+, which is present naturally in the seawater or is released from copper-containing paints, results in a partial transchelation of ZnPT2 into CuPT2. A complete transchelation of ZnPT2 into CuPT2 was observed when Cu2+ was present at an equimolar concentration in the absence of interfering ligands. When ZnPT2 was leached from antifouling paints containing both ZnPT2 and Cu2O, CuPT2 was found, with no trace of ZnPT2. Photodegradation was low in natural waters and absent from 1 m or more below the surface. The results show that ZnPT2 has a low persistence in seawater when leached from antifouling paints. However, the more stable and toxic transchelation product CuPT2 is formed, which has the potential to accumulate in the sediments and, therefore, should be included in both chemical analysis and risk assessment of ZPT2.
Comparative sediment quality guideline performance for predicting sediment toxicity in Southern California, USA
Authors: Vidal Doris E. , Bay Steven M. 
Published: November 2005

Abstract
Several types of sediment quality guidelines (SQGs) are used by multiple agencies in southern California (USA) to interpret sediment chemistry data, yet little information is available to identify the best approaches to use. The objective of this study was to evaluate the predictive ability of five SQGs to predict the presence and absence of sediment toxicity in coastal southern California: the effects range-median quotient (ERMq), consensus moderate effect concentration (consensus MEC), mean sediment quality guideline quotient (SQGQ1), apparent effects threshold (AET), and equilibrium partitioning (EqP) for organics. Large differences in predictive ability among the SQGs were obtained when each approach was applied to the same southern California data set. Sediment quality guidelines that performed well in identifying nontoxic samples were not necessarily the best predictors of toxicity. In general, the mean ERMq, SQGQ1q, and consensus MECq approaches had a better overall predictive ability than the AET and EqP for organics approaches. In addition to evaluating the predictive ability of SQGs addressing chemical mixtures, the effect of an individual SQG value (DDT) was also evaluated for the mean ERMq with and without DDT. The mean ERMq without DDT had a better ability to predict toxic samples than the mean ERMq with DDT. Similarities in discriminatory ability between different approaches, variations in accuracy among SQG values for some chemicals, and the presence of complex mixtures of contaminants in most samples underscore the need to apply SQGs in combination, such as the mean quotient. Management objectives and SQG predictive ability using regional data should be determined beforehand so that the most appropriate SQG approach and critical values can be identified for specific applications.
4-nonylphenol-induced toxicity and apoptosis in Hydra attenuata
Authors: Pachura Sophie , Cambon Jean-Pierre , Blaise Christian , Vasseur Paule 
Published: November 2005

Abstract
Effects of 4-nonylphenol (4-NP) onthe morphology and survival of the cnidarian Hydra attenuata were studied under acute exposure conditions. The lethal concentration value inducing 50% mortality after 96 h was 97.5 ± 20 μg/L, whereas the lethal concentration value inducing 10% mortality after 96 h was 64 ± 25.5 μg/L. The no-observed-effect concentration based on morphological criteria was less than 25 μg/L. Hydra was one of the most sensitive freshwater invertebrate species behind the amphipod Hyalella azteca. Toxicity effects appeared rapidly and did not evolve substantially between 24 and 96 h of exposure. Induction of apoptosis was registered during the first hour of exposure to 4-NP at lethal concentrations, indicating rapid effects of the chemical. Abnormal increase of apoptosis may explain the acute toxicity of 4-NP in hydra. Results show that hydra viability is affected in the short term at 4-NP concentrations normally found in contaminated sites, but not at those concentrations reflecting lower levels of environmental contamination.
Improved empirical models describing hormesis
Authors: Cedergreen Nina , Ritz Christian , Streibig Jens Carl 
Published: November 2005

Abstract
During the past two decades, the phenomenon of hormesis has gained increased recognition. To promote research in hormesis, a soudund statistical quantification of important parameters, such as the level and significance of the increase in response and the range of concentration where it occurs, is strongly needed. Here, we present an improved statistical model to describe hormetic dose—response curves and test for the presence of hormesis. Using the delta method and freely available software, any percentage effect dose or concentration can be derived with its associated standard errors. Likewise, the maximal response can be extracted and the growth stimulation calculated. The new model was tested on macrophyte data from multiple-species experiments and on laboratory data of Lemna minor. For the 51 curves tested, significant hormesis was detected in 18 curves, and for another 17 curves, the hormesis model described that data better than the logistic model did. The increase in response ranged from 5 to 109%. The growth stimulation occurred at an average dose somewhere between zero and concentrations corresponding to approximately 20 to 25% of the median effective concentration (EC50). Testing the same data with the hormesis model proposed by Brain and Cousens in 1989, we found no significant hormesis. Consequently, the new model is shown to be far more robust than previous models, both in terms of variation in data and in terms of describing hormetic effects ranging from small effects of a 10% increase in response up to effects of an almost 100% increase in response.
Slow desorption behavior of one highly resistant aromatic amine in Lake Macatawa, Michigan, USA, sediment
Authors: Chen Shihua , Nyman Marianne C. 
Published: November 2005

Abstract
The desorption behavior of benzidine from Lake Macatawa (Holland, MI, USA) sediment was investigated in this study using batch solvent extraction method. Seven solvents were tested as the extracting reagents: Deionized water (DI), calcium chloride in DI (CaCl2), sodium hydroxide in DI (NaOH), acetonitrile (ACN), a mixture of acetonitrile and ammonium acetate in DI (ACNNH4OAc), methanol (MeOH), and hydrochloric acid in DI (HCl). These solvents are proposed to react with sediment-associated benzidine by different mechanisms (e.g., cation exchange, hydrophobic partitioning, and covalent binding). Three sets of sorption isotherm experiments were conducted separately in these seven solvents with a 7-d, three-week, and two-month contact time. The results demonstrated nonlinear isotherms with Freundlich 1/n values varying from 0.25 to 0.52. The desorption behavior of benzidine in the solvents was evaluated after the sorption of benzidine onto the sediment with same contact times of 7 d, three weeks, and two months. A two-stage model subsequently was applied to simulate the experimental data. The rapidly desorbing rate constants were on the order of one to two per day for ACN, ACN-NH4OAc, and NaOH solvents, and the slowly desorbing rate constants were on the order of 10−5 to 10−4/d. Sequential desorption experiment demonstrated low total extraction efficiency of less than 40%. Both the observed sorption and desorption phenomena suggested that hysteresis and/or mass-transfer limited diffusion may result in the slow desorption behavior observed in this study.
Measuring sulfide accumulation in diffusive gradients in thin films by means of purge and trap followed by ion-selective electrode
Authors: Rearick Michael S. , Gilmour Cynthia C. , Heyes Andrew , Mason Robert P. 
Published: November 2005

Abstract
A procedure for measuring in situ sulfide concentrations by coupling diffusive gradients in thin films (DGT) to solid-state ion-selective electrodes (ISE) is described and evaluated. Laboratory tests were performed to evaluate the coupling of these techniques, and these results were compared to the previously used methods of computer imaging densitometry (CID) and methylene blue. An average elution efficiency of 89%, as detected by ISE, was determined for a series of solutions containing amounts of sulfide ranging from 0.009 to 2.50 μmol. The validity of the standard mass-transfer equation for sulfide accumulation by DGT probes and subsequent detection by ISE was tested by measuring the mass of sulfide collected over time and with respect to varying diffusive gel thicknesses. Regressions of the sulfide mass accumulation versus the independent variables of time and inverse diffusive thickness proved to be linear. The use of DGT coupled to ISE provides a preconcentration method for sulfide that improves the detection limit (DL) over other techniques. This alternative method provides quantitative measurements of DGT-captured sulfide from solutions with a detection limit of at least 0.1 μmol/L for a 24-h deployment. The DGT technique also provides potential advantages in understanding sulfide speciation over existing methods.
Effects of selected biocides used in the disinfection of cooling towers on toxicity and bioaccumulation in Artemia larvae
Authors: Bartolomé Maria Carmen , Sánchez-Fortún Sebastián 
Published: November 2005

Abstract
This paper reports the acute toxicity of three biocides used in the disinfection of cooling towers, tetrakis(hydroxymethyl) phosphonium chloride (THPC), trichloroisocyanuric acid (TCIC), and sodium bromide (NaBr), on Artemia larvae, their effect on the phototactic response of this organism, and the potential of bioaccumulation in this species. The 24-h median lethal concentration (LC50) values for these biocides with respect to 24-, 48-, and 72-h-old Artemia, determined by static bioassays, showed the following rank order of toxicity: THPC &lt; TCIC &lt; NaBr. An age-dependent increase in sensitivity was seen for each compound. All three biocides reduced the phototactic response of 24-h-old Artemia larvae in 24-h static bioassays; the median inhibitory concentration ratios obtained were 30 to 40 times lower than their respective 24-h LC50 values. The results suggest that phototaxis bioassays could provide the speed and simplicity required for screening many potential pollutants for harmful effects. The bioconcentration factors obtained for Artemia larvae exposed to 10% LC50 for 168 h in renewal assays were 93.75, 1.67, and 0.23 for THPC, TCIC, and NaBr, respectively. This shows these biocides pose no bioaccumulation risk in this organism, although the value of 93.75 obtained for THPC is close to the threshold above which such a risk is considered to exist.
A comparison of the lethal and sublethal toxicity of organic chemical mixtures to the fathead minnow (Pimephales promelas)
Authors: Broderius Steven J. , Kahl Michael D. , Elonen Gregory E. , Hammermeister Dean E. , Hoglund Marilynn D. 
Published: November 2005

Abstract
The joint toxic effects of known binary and multiple organic chemical mixtures to the fathead minnow (Pimephales promelas) were defined at both the 96-h 50% lethal effect concentration (LC50) and sublethal (32-d growth) response levels for toxicants with a narcosis I, narcosis II, or uncoupler of oxidative phosphoralation mode of toxic action. Experiments were designed to define the degree of additive joint toxicity for mixtures of specific xenobiotics that are believed to act through a similar or different primary mode of toxic action. Our results support the general conclusion that concentration addition is expected for the joint toxicity of similarly acting toxicants. When chemicals were thought to act by a dissimilar mechanism, the combined effects we observed at both of the response levels tested were less than predicted by concentration addition, but usually more toxic than that predicted by the independent action/response addition model. It was demonstrated in multichemical mixtures that several toxicants can act together in a nearly additive fashion to produce effects even when they are present at concentrations below their individual no-observed-effect concentration. Concentration-response relationships for test chemicals at both the lethal and sublethal responses were defined for each of the three modes of toxic action studied. When normalized for potency, it was observed that one relationship could be defined to predict lethality to juvenile fathead minnows when exposed to individual chemicals with either a narcosis I, narcosis II, or uncoupler mode of toxic action. These sublethal relationships were similar for the narcosis I and narcosis II test chemicals, but a steeper response was observed for tests conducted with uncouplers.
Behavioral response of Corophium volutator relative to experimental conditions, physical and chemical disturbances
Authors: Hellou Jocelyne , Cheeseman Kerri , Jouvenelle Marie-Laure , Robertson Sarah 
Published: November 2005

Abstract
The preference/avoidance behavioral response of a widely used amphipod in toxicity tests, Corophium volutator, was investigated in relation to the presence of anthropogenic physical or chemical materials in sediments. Exposure conditions, including the density of amphipods, the depth of sediments, amount of overlying water, and exposure time, were examined for their influence on amphipods' preference for field sediments and avoidance of coarse sand. It was shown that these variables did not affect the response; thus, conditions similar to published standard toxicity tests were chosen. A gradient of sediments spiked with potential habitat disturbances that can be found on a beach or in contaminated sediments, such as those in harbors, were tested. These substances included sand, seaweed, burned wood, coal, crankcase oil, and diesel oil. To enhance the interpretation of results and decrease the variability observed when tests were conducted at different times over the summer, exposures were performed over a gradient of spike material in reference sediments. We conclude that physical obstacles added to reference sediments lead to less correlation with the behavioral response than observed with chemical interferences. Amphipods' behavior ranked harbor sediments similarly to previous studies concerning the health of intertidal mussels collected in proximity to the sediments sites. For five sites, preference of reference sediments was observed until the level of polycyclic aromatic hydrocarbons in diluted harbor sediments reached the Canadian Council of Ministers of the Environment sediment quality guidelines.
Polychlorinated biphenyl 126 affects expression of genes involved in stress-immune interaction in primary cultures of rainbow trout anterior kidney cells
Authors: Quabius Elgar Susanne , Krupp Guido , Secombes Christopher J. 
Published: November 2005

Abstract
Stress and immune function are linked in all vertebrates, including teleost fish. Polychlorinated biphenyls (PCBs) are immunotoxic and impair the ability of fish to respond to additional stressors. In this study, we investigated the effects of PCB126 on stress and immune function and the interaction of these systems in fish using primary cultures of rainbow trout anterior kidney cells as a model. Gene expression levels of cytochrome P4501A (CYP1A), interleukin-1β (IL-1β), and glucocorticoid receptor (GR) were measured by real-time quantitative polymerase chain reaction. These genes play important roles in detoxification and immune and stress homeostasis, respectively. Incubation with PCB126 led to increased IL-1β expression between 30 min and 2 h of exposure, with expression back to basal levels after 6 h. Lipopolysaccharide (LPS) incubation evoked normal IL-1β responses after 2 and 24 h PCB incubation. Gene expression levels of GR and CYP1A increased in a time- and dose-dependent manner, reaching a plateau after 12 h of incubation. Preincubation with cortisol resulted in decreased IL-1β expression, increased expression of CYP1A and GR and was accompanied by an abolished PCB responsiveness after more than 4 h of cortisol incubation. We conclude that PCB126 exposure is not “stressful,” as increased cortisol levels would result in depressed IL-1β expression. Incubation with PCB126 evokes a transient stimulation rather than permanent damage of the immune system, as LPS stimulation resulted in increased IL-1β expression after PCB incubation. Prolonged cortisol preincubation, resembling a chronic stress paradigm, negatively affects the immune responsiveness of the cells as well as their capacity for toxicant metabolization.
Effects of storage aging on the cure kinetics of bismaleimide prepregs
Authors: Frigione M. , Kenny J. M. 
Published: November 2005

AbstractThe effects of room temperature aging on the subsequent polymerization kinetics of a bismaleimide (BMI) matrix prepreg, for high performance composites, have been characterized by different time and storage conditions. The study has focused on the stability of BMI matrix carbon fiber prepregs, when exposed to controlled environmental conditions before being used in composite manufacturing. The effects of aging on glass transition temperature, reactivity, and processability have been investigated by calorimetry through dynamic, isothermal, and cure‐simulating tests. A theoretical kinetic model for epoxy matrix prepregs, developed in previous studies, has been applied to the polymerization of both aged and unaged BMI matrix. The model is able to satisfactorily describe the effect of processing variables such as temperature and degree of reaction during the curing of the composite under different conditions (curing temperature and heating rate). The effects of diffusion‐controlled phenomena on the reaction kinetics, associated with changes in glass transition temperature as a function of the degree of polymerization and cross‐linking, have been taken into account in the formulation of an nth‐order kinetic model. © 2005 Wiley Periodicals, Inc. Adv Polym Techn 24: 253–265, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/adv.20048
Preparation and properties of room temperature self‐crosslinking poly(MMA‐co‐BA‐co‐St‐co‐VTES) latex film
Authors: Guo Tian Ying , Xi Chen , Hao Guang Jie , Song Mou Dao , Zhang Bang Hua 
Published: November 2005

AbstractSelf‐crosslinking poly(methyl methacrylate‐co‐n‐butyl acrylate‐co‐styrene‐co‐vinyltriethoxysilane) latex particles were prepared by seed emulsion polymerization. The presence of SiOSi in the prepared copolymer latex particle was confirmed by FT‐IR. The crosslinking degree of the polymer latex particle was investigated by using tetrahydrofuran to swell the dried copolymer films with different vinyltriethoxysilane contents. The thermal properties of the solid films were investigated by using DSC and TGA. In addition, the mechanical properties and water resistances of the different copolymer films were also investigated in detail. It was found that the mechanical properties of the copolymer film could be enhanced by introducing vinyltriethoxysilane, and the water resistance of the copolymer film could be improved at certain vinyltriethoxysilane contents. © 2005 Wiley Periodicals, Inc. Adv Polym Techn 24: 288–295, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/adv.20051
Looking back, and ahead: The Panama Convention after 30 years
Authors: Erickson Helena Tavares , Gupta Preeti , Sutter Philip 
Published: November 2005

AbstractThe pullout feature returns with history and future practice surrounding the Panama Convention. Helena Tavares Erickson, Preeti Gupta and Philip Sutter, of New York, provide tips for corporate counsel facing actions under the controlling arbitration treaty for U.S. companies doing business in Latin America.
Organizational learning capacity and attitude toward complex technological innovations: An empirical study
Authors: Teo Hock‐Hai , Wang Xinwei , Wei Kwok‐Kee , Sia Choon‐Ling , Lee Matthew K. O. 
Published: November 2005

AbstractRecent studies have found organizational learning capacity to be a key factor in influencing organizational assimilation and exploitation of knowledge‐intensive innovations. Despite its increasing importance, the impact of organizational learning capacity on technology assimilation is not well understood. Distilling from extant works on organizational learning and technology assimilation, this study identifies four components of organizational learning capacity, namely, systems orientation, organizational climate for learning orientation, knowledge acquisition and utilization orientation, and information sharing and dissemination orientation. The authors subject these components to structural equation modeling analyses to better understand their structure and dimensionality. The analyses strongly support the proposed four major dimensions underlying organizational learning capacity. Organizational learning capacity, as a higher‐order factor, has a significant impact on attitude towards organizational adoption of knowledge‐intensive innovations. Implications for practice and research are discussed.
Psychophysiological tests and provocation of subjects with mobile phone related symptoms
Authors: Wilén Jonna , Johansson Amanda , Kalezic Nebojsa , Lyskov Eugene , Sandström Monica 
Published: November 2005

AbstractThe aim of the present study was to investigate the effect of exposure to a mobile phone‐like radiofrequency (RF) electromagnetic field on persons experiencing subjective symptoms when using mobile phones (MP). Twenty subjects with MP‐related symptoms were recruited and matched with 20 controls without MP‐related symptoms. Each subject participated in two experimental sessions, one with true exposure and one with sham exposure, in random order. In the true exposure condition, the test subjects were exposed for 30 min to an RF field generating a maximum SAR1g in the head of 1 W/kg through an indoor base station antenna attached to a 900 MHz GSM MP. The following physiological and cognitive parameters were measured during the experiment: heart rate and heart rate variability (HRV), respiration, local blood flow, electrodermal activity, critical flicker fusion threshold (CFFT), short‐term memory, and reaction time. No significant differences related to RF exposure conditions were detected. Also no differences in baseline data were found between subject groups, except for the reaction time, which was significantly longer among the cases than among the controls the first time the test was performed. This difference disappeared when the test was repeated. However, the cases differed significantly from the controls with respect to HRV as measured in the frequency domain. The cases displayed a shift in low/high frequency ratio towards a sympathetic dominance in the autonomous nervous system during the CFFT and memory tests, regardless of exposure condition. This might be interpreted as a sign of differences in the autonomous nervous system regulation between persons with MP related subjective symptoms and persons with no such symptoms. Bioelectromagnetics 27:204–214, 2006. © 2005 Wiley‐Liss, Inc.