bluuebunny/crossref_metadata_2025_split huggingface dataset:
Changes in biogeochemical cycling following forest defoliation by pine wilt disease in Kiryu experimental catchment in Japan
Authors: Tokuchi Naoko , Ohte Nobuhito , Hobara Satoru , Kim Su‐Jin , Masanori Katsuyama 
Published: October 2004

AbstractChanges in nutrient budgets and hydrological processes due to the natural disturbance of pine wilt disease (PWD) were monitored in a small, forested watershed in Japan. The disturbance caused changes in soil nitrogen transformations. Pre‐disturbance, mineralized nitrogen remained in the form of NH4+, whereas in disturbed areas most mineralized nitrogen was nitrified. Stream NO3− concentrations increased following PWD. There was a delay between time of disturbance and the increase of NO3− in ground and stream waters. Stream concentrations of NO3− and cations (Ca2+ + Mg2+) were significantly correlated from 1994 to 1996, whereas the correlation among NO3−, H+, and SO42− was significant only in 1995. Although both cation exchange and SO42− adsorption buffered protons, cation exchange was the dominant and continuous mechanism for acid buffering. SO42− adsorption was variable and highly pH dependent. The disturbance also resulted in slight delayed changes of input–output nutrient balances. The nitrogen contribution to PWD litter inputs was 7·39 kmol ha−1, and nitrogen loss from streamwater was less than 0·5 kmol ha−1 year−1 throughout the observation period. This large discrepancy suggested substantial nitrogen immobilization. Copyright © 2004 John Wiley & Sons, Ltd.
Matrix hydrodynamic properties of carbonate rocks from the Betic Cordillera (Spain)
Authors: Pulido‐Bosch A. , Motyka J. , Pulido‐Leboeuf P. , Borczak S. 
Published: October 2004

AbstractLaboratory tests performed on 181 rock samples from boreholes drilled in different areas of the Betic Cordillera allow us to calculate their hydraulic conductivity and open porosity values. Higher values are generally associated with Miocene calcareous sandstones, although hydraulic conductivity reaches its highest values in some isolated limestone and dolostone samples. Lower values were found in marly limestones and marbles. Specific yield ranged from 0 to 0·0798, with a mean value of 0·00579. A total of 79 samples did not release water during the specific yield test, while another 11 samples released water for more than 30 min. Such wide ranges of variation show the great diversity of behaviour that the matrix of the carbonate rocks can have, referring to water storage and transfer, and its influence on pollutants spread, for example. A weak relation between interconnected porosity and hydraulic conductivity was found. The relation between interconnected porosity and specific yield is slightly stronger, except in the case of the dolomites, where a high correlation was found. No dependence on depth was found for hydraulic conductivity and interconnected porosity. Copyright © 2004 John Wiley & Sons, Ltd.
Estimates of flow resistance and eddy viscosity coefficients for 2D modelling on vegetated floodplains
Authors: Vionnet C. A. , Tassi P. A. , Martín Vide J. P. 
Published: October 2004

AbstractThe problem of quantifying the effects of flexible plants on flow resistance and eddy viscosity by vegetated floodplains is first addressed with a one‐dimensional (1D) approximation based upon the so‐called lateral distribution method. The estimates so obtained are then tested with two‐dimensional (2D) numerical simulations based on the full shallow water equations through the use of the computational code Telemac‐2D. Data obtained on a physical model of the Besòs River (Spain), whose floodplains were covered with plastic ornamental plants to mimic the effect of flexible vegetation, is used for the validation of the numerical results. Additionally, the values of flow resistance estimated numerically with the 1D and 2D simulations are compared with values obtained in a rectangular flume under flow conditions (slope, water depth and artificial lining) similar to those used on the reduced model. It is then established that as more physical mechanisms are included in the mathematical model used to study the problem, the ratio between the floodplain and the main channel flow resistance coefficient increases. The approach demonstrates that whenever enough flow data is available, the lateral distribution method delivers values of flow resistance and eddy viscosity which are highly consistent with 2D numerical modelling. This finding could mean considerable savings in the burdensome task of specifying flow resistance and turbulence dissipation values for 2D modelling of large compound channel systems. Copyright © 2004 John Wiley & Sons, Ltd.
Protein‐like fluorescence intensity as a possible tool for determining river water quality
Authors: Baker Andy , Inverarity Roger 
Published: October 2004

AbstractThe results of a comparison between chemical water quality determinants and river water fluorescence on the River Tyne, NE England, demonstrate that tryptophan‐like fluorescence intensity shows statistically significant relationships between nitrate, phosphate, ammonia, biochemical oxygen demand (BOD) and dissolved oxygen. Tryptophan‐like fluorescence intensity at the 280 nm excitation/350 nm emission wavelength fluorescence centre correlates with both phosphate (r = 0·80) and nitrate (r = 0·87), whereas tryptophan‐like fluorescence intensity at the 220 nm excitation/350 nm emission wavelength centre correlates with BOD (r = 0·85), ammonia (r = 0·70) and dissolved oxygen (r = −0·65). The strongest correlations are between tryptophan‐like fluorescence intensity and nitrate and phosphate, which in the Tyne catchment derive predominantly from point and diffuse source sewage inputs. The correlation between BOD and the tryptophan‐like fluorescence intensity suggests that this fluorescence centre is related to the bioavailable or labile dissolved organic matter pool. The weakest correlations are observed between tryptophan‐like fluorescence intensity and ammonia concentration and dissolved oxygen. The weaker correlation with ammonia is due to removal of the ammonia signal by wastewater treatment, and that with dissolved oxygen due to the natural aeration of the river such that this is not a good indicator of water quality. The observed correlations only hold true when treated sewage, sewerage overflows or cross connections, or agricultural organic pollutants dominate the water quality—this is not true for two sites where airport deicer (propylene glycol, which is non‐fluorescent) or landfill leachate (which contains high concentrations of humic and fulvic‐like fluorescent DOM) dominate the dissolved organic matter in the river. Mean annual tryptophan‐like fluorescence intensity agrees well with the General Water Quality Assessment as determined by the England and Wales environmental regulators, the Environment Agency. Copyright © 2004 John Wiley & Sons, Ltd.
Sensitivity evaluation of the Daphtoxkit and Thamnotoxkit microbiotests on blind samples
Authors: Törökné Andrea 
Published: October 2004

AbstractAt the Oregon State University Workshop we utilized two ‘culture/maintenance‐free’ microbiotests, the Thamnotoxkit F™ with the anostracan crustacean Thamnocephalus platyurus and the Daphtoxkit F™ magna with the cladoceran crustacean Daphnia magna, to determine the toxicity of water samples in a blind format. The Thamnotoxkit was applied to 7 samples and the Daphtoxkit to 12 samples. The chemical composition of the water samples to which the Toxkit microbiotests had been applied was disclosed a posteriori by the organizers and appeared to contain chlordimeform, colchicine, phosdrin, mercuric chloride, sodium arsenite, metham sodium, sodium cyanide, trimethylol propane phosphate, p‐chlorophenol and a natural sediment sample containing mercury. Three of the water samples were blanks that had not been spiked with chemicals. No false positives were obtained with the two Toxkits and all the toxic waters were earmarked as such by the microbiotests, except trimethylol propane phosphate, which was not found to induce acute effects in Daphnia magna in the non‐diluted water sample containing 100 mg l−1 of this compound. Copyright © 2004 John Wiley & Sons, Ltd.
EILATox‐Oregon Workshop: blind study evaluation of vitotox test with genotoxic and cytotoxic sample library
Authors: Meriläinen Jari , Lampinen Jorma 
Published: October 2004

AbstractIn order to assess the robustness, sensitivity and speciﬁcity of a recently developed Vitotox™ test, 17 blind coded chemicals and three environmental water samples were tested at the EILATox‐Oregon Workshop using the Thermo Electron Vitotox kit. The Vitotox test is a rapid geno‐ and cytotoxicity test using standard 96‐ or 384‐well microtitre plates. The genotoxicity test is based on two genetically modiﬁed Salmonella typhimurium strains containing bacterial luciferase operon from Vibrio ﬁsheri under the SOS inducible promoter. The SOS system is an inducible network in Escherichia coli that responds to DNA damage and activates DNA repair. The Vitotox genotoxicity test bacteria strain carries bacterial luciferase genes under the control of SOS inducible promoter and therefore any DNA damage inside the cells induces the production of bacterial luciferase. The luciferase expression is then followed with a microtitre plate luminometer for 3 h after mixing different dilutions of sample with the test bacteria. The genotoxicity index is calculated for each dilution and the genotoxicity of the sample is interpreted based on kinetic time curves and genotoxicity vs concentration/dilution curves. Cytotoxicity of the sample is determined simultaneously with another test strain containing the same luciferase operon controlled by the constitutive promoter. This bacterium produces constant bioluminescence and any decrease of the bioluminescence production is used as a marker for cytotoxicity.As a miniaturized microtitre plate assay the Vitotox test requires a very small quantity of the sample material. The samples used in the workshop were diluted 1 : 10 or 1 : 100 before testing. Genotoxicity and cytotoxicity data were collected at dilutions of 1 : 10–1 : 2000. When the samples of the EILATox‐Oregon Workshop were tested using the Vitotox test, four coded chemicals out of 17 were determined to be genotoxic. Seven chemicals and one environmental sample were found to be cytotoxic. Three chemical samples were found to be both geno‐ and cytotoxic. Copyright © 2004 John Wiley & Sons, Ltd.
Detection of bioavailable heavy metals in EILATox‐Oregon samples using whole‐cell luminescent bacterial sensors in suspension or immobilized onto fibre‐optic tips
Authors: Hakkila Kaisa , Green Tal , Leskinen Piia , Ivask Angela , Marks Robert , Virta Marko 
Published: October 2004

AbstractAt the EILATox‐Oregon Workshop, nine luminescent whole‐cell bacterial sensors were used for the determination of bioavailable metals in blind samples (17 synthetic and 3 environmental). A non‐inducible luminescent control strain was used to determine sample matrix effects and bacterial toxicity. Whole‐cell bacterial sensors capable of determining arsenic, inorganic mercury and its organic derivatives, cadmium, lead or copper were used in suspensions and a bacterial sensor for the detection of inorganic mercury was immobilized onto ﬁbre‐optic tips using calcium alginate. Bioavailable amounts of metals were estimated using calibration plots, that were constructed to determine the range of metals giving rise to a linear relationship between luminescence and the amount of metals present in the standard solutions. EILATox‐Oregon sample 5, which contained 74 mg l−1 of Hg, gave a signiﬁcant response with both formats of the mercury sensor. The bioavailable amounts of mercury according to the measurement of bacterial sensor in suspension and immobilized onto a ﬁbre‐optic tip were 76 and 93 mg l−1, respectively. The bacterial sensor for arsenic and copper showed a response with sample 6 (58 mg l−1 of As) and sample 8 (400 mg l−1 of metham sodium), respectively. This study showed that the bacterial sensors in suspension or immobilized onto optical ﬁbres are capable of quantifying bioavailable metals from unknown samples. The measurement protocol of bacterial sensors is simple and possible to perform in the ﬁeld. Moreover, the samples do not need any pretreatment before analysis. Construction and characterization of the strain for the detection of bioavailable copper are described. Copyright © 2004 John Wiley & Sons, Ltd.
Toxicity detection from EILATox‐Oregon Workshop samples by using kinetic photobacteria measurement: the flash method
Authors: Hakkila Kaisa , Lappalainen Juha , Virta Marko 
Published: October 2004

AbstractThe Flash test, which can be used to measure the toxicity from clear, turbid and coloured samples with identical protocol, was used in the EILATox‐Oregon Workshop. During the workshop, 17 synthetic samples and three environmental samples were tested. In the Flash method the photobacteria Vibrio ﬁscheri are initially dispensed on top of the sample and the light output of the bioluminescence reaction is recorded at a rate of several readings per second. The change in the light production was measured at two points: 30 s and 30 min after exposure at room temperature. Toxicity calculations were done by using either the peak height of the sample or the peak height of the control sample (maximum signal at 0–2 s). When the peak height of the sample is used as a reference, the colour and turbidity effect of solid particles are taken into account throughout the whole measurement period. In the EILATox‐Oregon Workshop toxicity was seen in samples 1 (chlordimeform), 4 (phosdrin), 5 (HgCl2), 6 (sodium arsenite), 8 (metham sodium), 12 (p‐chlorophenol), 14 (sodium selenite) and 17 (MNNG). Only samples 1, 4 and 12 showed different ec50 values between different calculations of toxicity. The ec50 values were calculated and compared with the ec50 values of Microtox derived from the literature. The Flash test will not replace the standardized photobacteria test, but is the advanced version of it and is needed when the sample matrix is complex and when speed and low costs are required. Copyright © 2004 John Wiley & Sons, Ltd.
Blind and naïve classiﬁcation of toxicity by fish chromatophores
Authors: Mojovic Ljiljana , Dierksen Karen P. , Upson Rosalyn H. , Caldwell Bruce A. , Lawrence Jeannine R. , Trempy Janine E. , McFadden Philip N. 
Published: October 2004

AbstractCellular and molecular pathways involved in the ability of animals to change color have been studied previously as biosensors and cytosensors of active and toxic agents, but such studies generally have been limited to just a few standardized agents. Here we describe the performance of cultured chromatophore pigment cells from the ﬁn tissue of Siamese ﬁghting ﬁsh as sensors of toxic agents under blind sampling conditions at the September 2002 EILATox‐Oregon Workshop. Detection was accomplished by monitoring motor protein‐mediated movements of cellular pigment in chromatophores at both the gross population level as well as in singly imaged cells. Pigment responses were recorded both during the exposure of chromatophores to each blind sample as well as afterwards when the cells were examined for after‐effects by challenging them with clonidine, an adrenergic drug that induces standardized pigment movements. After recording all results and upon breaking the key to reveal the identities of the toxic agents, it was found that all of the toxic samples in the study had been distinguished accurately from non‐toxic controls that were included among the blind samples. Furthermore, it was revealed that most of the toxic agents detected had never before been tested or calibrated against chromatophores, demonstrating that detection can be achieved under naïve conditions that have not been optimized for the analysis of any particular toxic agent. Finally, by organizing the results into categories of pigment responses, a binary classiﬁcation tree was generated that distinguished each toxic agent as having a distinct response pattern from the others. Thus, chromatophore‐based cytosensors can discover toxicity in the absence of prior knowledge of the agent in question, and the categories of responses of the cells can be used to distinguish one toxic agent from another. Copyright © 2004 John Wiley & Sons, Ltd.
Water toxicity detection by a panel of stress‐responsive luminescent bacteria
Authors: Pedahzur R. , Polyak B. , Marks R.S. , Belkin S. 
Published: October 2004

AbstractA panel of Escherichia coli strains harbouring different stress‐responsive promoters fused to a lux reporter system was used to assess the potential toxicity of 17 unknown model water samples. Using liquid cultures, nine out of 14 toxic samples were properly identiﬁed as toxic, whereas ﬁve were false negatives. All three non‐toxic controls were identiﬁed correctly (no false positives). Two strains containing promoter–lux fusions were also tested when immobilized onto ﬁbre‐optic tips. One genotoxic sample and six toxic samples were correctly identiﬁed in this manner. The potential advantages and limitations in the use of genetically engineered bacteria as biosensors for water toxicity are discussed in view of these results. Copyright © 2004 John Wiley & Sons, Ltd.
Detection and classiﬁcation of threat agents via high‐content assays of mammalian cells
Authors: Tencza Sarah B. , Sipe Michael A. 
Published: October 2004

AbstractOne property common to all chemical or biological threat agents is that they damage mammalian cells. A threat detection and classiﬁcation method based on the effects of compounds on cells has been developed. This method employs high‐content screening (HCS), a concept in drug discovery that enables those who practice cell‐based assays to generate deeper biological information about the compounds they are testing. A commercial image‐based cell screening platform comprising ﬂuorescent reagents, automated image acquisition hardware, image analysis algorithms, data management and informatics was used to develop assays and detection/classiﬁcation methods for threat agents. These assays measure a cell's response to a compound, which may include activation or inhibition of signal transduction pathways, morphological changes or cytotoxic effects. Data on cell responses to a library of compounds was collected and used as a training set. At the EILATox‐Oregon Workshop, cellular responses following exposure to unknown samples were measured by conducting assays of p38 MAP kinase, NF‐κB, extracellular‐signal related kinase (ERK) MAP kinase, cyclic AMPresponse element binding protein (CREB), cell permeability, lysosomal mass and nuclear morphology. Although the assays appeared to perform well, only four of the nine toxic samples were detected. However the system was speciﬁc, because no false positives were detected. Opportunities for improvement to the system were identiﬁed during the course of this enlightening workshop. Some of these improvements were applied in subsequent tests in the Cellomics laboratories, resulting in a higher level of detection. Thus, an HCS approach was shown to have potential in detecting threat agents, but additional work is necessary to make this a comprehensive detection and classiﬁcation system. Copyright © 2004 John Wiley & Sons, Ltd.
Cultured neuronal networks as environmental biosensors
Authors: O'Shaughnessy Thomas J. , Gray Samuel A. , Pancrazio Joseph J. 
Published: October 2004

AbstractContamination of water by toxins, either intentionally or unintentionally, is a growing concern for both military and civilian agencies and thus there is a need for systems capable of monitoring a wide range of natural and industrial toxicants. The EILATox‐Oregon Workshop held in September 2002 provided an opportunity to test the capabilities of a prototype neuronal network‐based biosensor with unknown contaminants in water samples. The biosensor is a portable device capable of recording the action potential activity from a network of mammalian neurons grown on glass microelectrode arrays. Changes in the action potential ﬁring rate across the network are monitored to determine exposure to toxicants. A series of three neuronal networks derived from mice was used to test seven unknown samples. Two of these unknowns later were revealed to be blanks, to which the neuronal networks did not respond. Of the ﬁve remaining unknowns, a signiﬁcant change in network activity was detected for four of the compounds at concentrations below a lethal level for humans: mercuric chloride, sodium arsenite, phosdrin and chlordimeform. These compounds — two heavy metals, an organophosphate and an insecticide — demonstrate the breadth of detection possible with neuronal networks. The results generated at the workshop show the promise of the neuronal network biosensor as an environmental detector but there is still considerable effort needed to produce a device suitable for routine environmental threat monitoring. Copyright © 2004 John Wiley & Sons, Ltd.
Use of a complex approach for assessment of metamizole sodium and acetylsalicylic acid toxicity, genotoxicity and cytotoxicity
Authors: Arkhipchuk V. V. , Goncharuk V. V. , Chernykh V. P. , Maloshtan L. N. , Gritsenko I. S. 
Published: October 2004

AbstractA complex approach based on the use of test organisms belonging to different systematic groups (plants, invertebrates and vertebrates), as well as the nucleolar biomarker and the micronucleus test on their cells, was applied to assess the toxicity, cytotoxicity and genotoxicity of two pharmaceutical substances (metamizole sodium and acetylsalicylic acid) applied at ic50 concentrations for mammalian cells. The compound acetylsalicylic acid was evaluated at a concentration (1.6 × 103 mg l−1) that was non‐toxic for bioassays based on ﬁsh (Carassius auratus gibelio) and hydra (Hydra attenuata) and acutely toxic for bioassays with ceriodaphnia (Ceriodaphnia afﬁnis) and onion (Allium cepa). The metamizole sodium solution (6.25%) demonstrated acute toxicity for the whole set of test organisms. Both drugs, after their 30–360 min inﬂuence on the test organisms, ﬁrst changed the nucleolar size in plant and animal cells (i.e. the transcriptional activity of ribosomal genes was affected most signiﬁcantly). Moreover, the metamizole sodium solution caused nucleolar structural damage in 90% of hydra cells as early as after 30 min of exposure. The acetylsalicylic acid solution inhibited essentially the rate of cell division in the meristem of onion roots (the mitotic index decreased to 9.6‰, as compared 51.7‰ for the control). The carp incubation and the onion germination in the acetylsalicylic acid solution showed a reproducible increase in the frequency of cells with micronuclei (2 and 5.5 times, respectively) and double nuclei (3 and 1.5 times, respectively). The approach described herein may be applied for obtaining rapid, cost‐efﬁcient and useful supplementary data on different types of toxicity for marketed drugs as well as for drugs under development. Copyright © 2004 John Wiley & Sons, Ltd.