bluuebunny/crossref_metadata_2025_split huggingface dataset:
Disease in a Caesarian-Derived Albino Rat Colony and in a Conventional Colony
Authors: Bell Deirdre P. 
Published: June 2007

A small caesarian-derived colony of albino rats was established in 1960 and has been maintained apparently free of specific pathogens by a simple and inexpensive method. The prevalence of disease, parasite infestations and other abnormalities has been compared in the caesarian-derived colony with rats of the same strain kept under conventional conditions. The investigation has shown that rats of the caesarian-derived colony were free from chronic respiratory disease, lice, worms in the urinary bladder, tape-worms, bartonellosis, salmonellosis, labyrinthitis and various minor infections, all of which were prevalent in rats kept under conventional conditions. Animals of both colonies were subject to a low incidence of tumours, which were of various types in the caesarian-derived rats but mainly mammary carcinomas in the controls. A haemorrhagic hepatic disease occurred for a short time in both colonies. The most prevalent congenital abnormality was one associated with hydronephrosis, pyelonephritis and a haemorrhagic renal disease; both colonies had a similar prevalence of these lesions. Occasional cases of hydrocephalus, situs inversus, cleft lip and cleft palate, microphthalmia and absent organs were observed in both colonies. The study has indicated that there are considerable advantages in using caesarian-derived rats in preference to conventional stock in experimental work.
Susceptibility of caesarian-derived rats to natural infection with chronic respiratory disease
Authors: Bell Deirdre P. , Wheeler Sylvia M. 
Published: June 2007

Young caesarian-derived rats, sharing cages with conventional rats, developed chronic respiratory disease after 2 months if the conventional rats were young, and after 1 month if they were old. Old caesarian-derived rats developed the disease after only 2 weeks of exposure, irrespective of the age of the cage mate. In long-term experiments, caesarian-derived rats acquired chronic respiratory disease from conventional rats even when kept separately in wiremesh cages adjacent to theirs. If caesarian-derived rats were kept in a separate cage 4 feet away from infected stock more than 1/3 of the rats did not develop chronic respiratory disease, and in the remainder the disease was retarded. When facilities are restricted and it is desirable to use caesarian-derived stock these, if young, could be housed with young conventional rats for up to 2 months with little risk of developing chronic respiratory disease.
Manifolds with asymptotically nonnegative minimal radial curvature
Authors: Santos Newton L 
Published: June 2007

Abstract
In this paper we extend results on the geometry of manifolds with asymptotically nonnegative curvature to manifolds with asymptotically nonnegative minimal radial curvature, showing that most of the results obtained by [U. Abresch, Lower curvature bounds, Toponogov's theorem, and bounded topology. Ann. Sci. École Norm. Sup. (4) 18 (1985), 651–670. MR839689 (87j:53058) Zbl 0595.53043], [A. Kasue, A compactification of a manifold with asymptotically nonnegative curvature. Ann. Sci. École Norm. Sup. (4) 21 (1988), 593–622. MR982335 (90d:53049) Zbl 0662.53032] and [S.-H. Zhu, A volume comparison theorem for manifolds with asymptotically nonnegative curvature and its applications. Amer. J. Math.
116 (1994), 669–682. MR1277451 (95c:53049) Zbl 0953.53027] hold in a more general context. Particularly, we show that there exists one and only one tangent cone at infinity to each such manifold, in contrast with the class of manifolds of nonnegative Ricci curvature.
Hermitian indicator sets
Authors: Cossidente A , Lunardon G , Marino G , Polverino O 
Published: June 2007

Abstract
Indicator sets arising from symplectic line-spreads of a 3-dimensional projective space are characterized. Moreover, locally Hermitian ovoids of a Hermitian surface

(3, q
2) are studied in terms of “non-equivalent” associated indicator sets. Translation locally Hermitian ovoids of

(3, q
2) arising from regular spreads of PG(3, q), Kantor semifield spreads of PG(3, q) and semifield spreads of PG(3, q) with center

are also investigated.
Intersection properties of polyhedral norms
Authors: Moreno José Pedro , Schneider Rolf 
Published: June 2007

Abstract
We investigate the family

of intersections of balls in a finite-dimensional vector space with a polyhedral norm. The spaces for which

is closed under Minkowski addition are completely determined. We characterize also the polyhedral norms for which

is closed under adding a ball. A subset

of

consists of the Mazur sets K, defined by the property that for any hyperplane H not meeting K there is a ball containing K and not meeting H. We characterize the Mazur sets in terms of their normal cones and also as summands of closed balls. As a consequence, we characterize the polyhedral spaces with only trivial Mazur sets as those whose unit ball is indecomposable.
Shell Strength and Appearance in Cultured Blue Mussels Mytilus edulis, M. trossulus, and M. edulis × M. trossulus Hybrids
Authors: Penney Randy W , Hart M Jeanne , Templeman Nadine D 
Published: June 2007

Abstract
We studied shell strength and appearance in six mixed-species cultured populations of blue mussels (Mytilus edulis, M. trossulus, and their hybrids) from Newfoundland, Canada. Shell strength (defined as the force causing shell breakage) and shell thickness both increased with shell length. Strength and thickness varied significantly among sites and among genotypes within sites; M. edulis had stronger and thicker shells than M. trossulus. Shell strength was related to shell thickness and shell width, both of which were greater in M. edulis than in M. trossulus. Hybrids tended to be intermediate. Appearance was studied on the basis of shell color and shape. The frequency of brown-shelled mussels varied considerably among sites and was higher in M. trossulus than in M. edulis. Shell width, depth, width-length ratio, and depth-length ratio all varied significantly among sites. Within sites, M. edulis had a greater shell width, width-length ratio, and width-depth ratio than M. trossulus, whereas hybrids were intermediate. Intrasite variability in shell shape characteristics, expressed as total population variance, was greater in the mixed-species populations from Newfoundland than in a unispecific M. edulis population from Prince Edward Island. In a reciprocal seed transfer experiment, shell width, width-length ratio, and width-depth ratio were greater in M. edulis than in M. trossulus of similar age. Width-length and width-depth ratios decreased with increasing age. Fourteen months after transfer, shell width and depth differed between transferred and nontransferred stocks. Interspecific relationships between M. edulis and M. trossulus in shell width and width-length ratio were similar in transferred and nontransferred stocks, while the other shell dimensions and their ratios differed. We infer that genotype-related differences in shell shape may change after stock transfer owing to site-related effects on shell growth. We discuss these results in terms of their potential impact on future industry development, particularly expansion of the seed supply for further industry growth.
Efficiency of Trout Raceway Quiescent Zones in Controlling Suspended Solids
Authors: Soderberg Richard W 
Published: June 2007

Abstract
Best management practice for effluent control of trout hatchery discharges calls for separation of cleaning waste by collection in quiescent zones (QZs) at the end of each raceway. The efficiency of QZs in trapping solid waste over a range of fish densities, water velocities, and QZ areas, measured by overflow rate (OFR), were studied. Solids retention in the QZs was negligible at velocities of 2.0 and 4.4 cm/s (regardless of fish density) and at a fish density of 40 kg/m3 (regardless of velocity). Solids collection efficiency was affected more by OFR and fish density than by velocity. At OFRs of 0.5 and 1.0 cm/s, solids collection was significantly better at a fish density of 160 kg/m3 than at a density of 80 kg/m3. At a density of 80 kg/m3, solids retention was better at an OFR of 0.5 cm/s than at an OFR of 1.0 cm/s. Solids retention was not affected by OFR at a fish density of 160 kg/m3. Velocities in the range of 2.4–3.4 cm/s did not affect solids collection efficiency at either fish density. Thus, optimum conditions for solids collection in trout raceway QZs were 2.4–3.4-cm/s velocity and (1) a fish density of 160 kg/m3 at an OFR of 0.5 or 1.0 cm/s or (2) a density of 80 kg/m3 at an OFR of 0.5 cm/s. Under these conditions, up to 20% of the total solids load was collected in the raceway QZs. Although this value is lower than expected based on the literature, actual solids levels were less than 5 mg/L and solids concentrations in the effluents of downstream units of serial raceways were not additive.
Status of an Introgressed Guadalupe Bass Population in a Central Texas Stream
Authors: Littrell Bradley M. , Lutz-Carrillo Dijar J. , Bonner Timothy H. , Fries Loraine T. 
Published: June 2007

Abstract
Introductions of nonnative smallmouth bass Micropterus dolomieu into central Texas streams resulted in introgressive hybridization with an endemic allopatric congener, the Guadalupe bass M. treculii. The objectives of this study were to use the variation at 14 microsatellite DNA loci to examine the frequencies of Guadalupe bass, smallmouth bass, and their hybrids 10 years after supplemental stockings of Guadalupe bass in the Blanco River. Genetic analysis identified 40% of individuals as smallmouth bass, 51% as smallmouth bass × Guadalupe bass hybrids, and 9% as other Micropterus hybrids. Pure Guadalupe bass were not collected. Despite supplemental stocking, the frequency of pure Guadalupe bass appears to have declined in the Blanco River in the past 10 years. These results emphasize the need for a current survey of the genetic status of the species throughout its native range.
Diel Behavior of Adult Striped Bass Using Tailwater Habitat as Summer Refuge
Authors: Young Shawn P. , Isely J. Jeffery 
Published: June 2007

AbstractGeneral patterns of summer diel distribution and movement were identified for adult striped bass Morone saxatilis using tailwater habitat influenced by the diel operation cycle of a hydroelectric dam during the summers of 2003 and 2004. Striped bass distribution within the tailwater was similar during each diel‐tracking event and across both summers. The majority of fish remained within the tailwater the entire summer; however, some made periodic excursions to and from the tailwater throughout the summer. Further, most striped bass were located within 0.5 km of Richard B. Russell Dam during all stages of operation on all occasions—probably because of the constant availability of optimal habitat during all three stages of operation on all diel‐tracking events. The diel cycle of dam operation, which included pumped storage during each summer, did not degrade tailwater habitat below optimal conditions, according to summer habitat suitability index values for inland adult striped bass. Movement was significantly higher during hydroelectric generation operations than during no‐generation and pumped storage periods in summer 2003; this difference was not apparent during summer 2004. Mean absolute movement peaked during hydroelectric generation on six of eight diel‐tracking events. During both summers, movement was directed up‐reservoir during no‐generation and generation periods and down‐reservoir during pumped storage. Mean total daily movement rates ranged from 0.59 to 4.04 km/d and were greater than those previously estimated from bimonthly sampling for this population. Total daily movement rate peaked during the first tracking event each summer and then declined as summer progressed. These findings suggest that hydroelectric discharges affect adult striped bass behavior, but the effects are not adverse as long as habitat is not degraded by hydroelectric facility operations.
The use of coarse, separable, condensed-phase organic carbon particles to characterize desorption resistance of polycyclic aromatic hydrocarbons in contaminated sediments
Authors: Chai Yunzhou , Kochetkov Alexander , Reible Danny D. 
Published: June 2007

Abstract
Physical separations were employed to characterize the source of desorption-resistant behavior for polycyclic aromatic hydrocarbons (PAHs) in laboratory- and field-contaminated sediments. Size and density separation of laboratory-contaminated sediments did not effectively separate the amorphous-phase (volatile) and condensed-phase (nonvolatile) organic carbon as measured by thermal oxidation at 375°C. These separations also did not result in sediment fractions with significantly different desorption characteristics as measured by apparent partition coefficients. Coarse particles from a field-contaminated sediment from Utica Harbor (UH; Utica, NY, USA), however, could be directly separated into sandy fractions and organic fractions that were composed of woody organic matter, charcoal or charred vegetative matter, and coal-like and coal-cinder particles. Chemical analysis showed that coal-like (glassy, nonporous) and coal-cinder (porous, sintered) particles exhibited very high PAH concentrations and high apparent partition coefficients. These particles also exhibited significantly higher condensed-phase (nonvolatile) organic carbon contents as defined by thermal oxidation at 375°C. The apparent partition coefficients of PAHs in the coal-cinder particles were a good indication of the apparent partition coefficients in the desorption-resistant fraction of UH sediment, indicating that the coarse particles provided a reasonable characterization of the desorption-resistance phenomena in these sediments even though the coarse fractions represented less than 25% of the organic carbon in the whole sediment.
Deterministic and probabilistic acute-based environmental risk assessment for naproxen for Western Europe
Authors: Straub Jürg Oliver , Stewart Kathleen M. 
Published: June 2007

Abstract
An environmental risk assessment (ERA) was made for the common nonsteroidal anti-inflammatory drug naproxen. The ERA was performed according to deterministic and probabilistic methods, based on different predicted environmental concentrations (PECs) and measured environmental concentrations (MECs) on the exposure side as well as on published and newly elaborated acute ecotoxicity data on the effects side. Compilation of a large set of MECs allowed a qualification of the various PEC derivations. The European Medicines Evaluation Authority (EMEA) phase I PEC was shown to be far above realistic values, while the refined EMEA phase II (A and B) PECs were not too far from the 95th percentile MEC, in agreement with their nature as local PECs. The western European continental and regional PECs extrapolated based on actual use data, using the European Union system for the evaluation of substances, with the region reconfigured for Germany where most of the available European MECs are from, were in good to very close agreement with the median MECs. No risk to surface waters is apparent by any of the methodologies applied from the current use of naproxen; however, because only insufficient chronic ecotoxicity data are available, this is a preliminary conclusion.
Assessment of the toxicity of mixtures of nickel or cadmium with 9,10-phenanthrenequinone toDaphnia magna: Impact of a reactive oxygen-mediated mechanism with different redox-active metals
Authors: Xie Fangli , Lampi Mark A. , Dixon D. George , Greenberg Bruce M. 
Published: June 2007

AbstractRecently, we showed that reactive oxygen species (ROS) formation was involved in the toxicity of the redox-active metal Cu and mixtures of Cu plus a photomodified polycyclic aromatic hydrocarbon (PAH), phenanthrenequinone (PHQ), to Daphnia magna. It is unknown, however, if similar results can be observed for metals with lower or no redox activity and their mixtures with PHQ. In the present study using D. magna, the toxicity of Ni, a weakly redox-active metal, and of Cd, a non-redox active metal, was examined with or without PHQ. The abilities of Ni, Cd, PHQ, and binary mixtures of metal plus PHQ to generate ROS were measured using a 2′,7′-dichlorofluorescein fluorescence assay. The results were compared with the results of Cu and mixtures of Cu plus PHQ from a recent study by our group. The order of metal toxicity to D. magna was found to be Cd ≥ Cu &gt; Ni. As with Cu/PHQ mixtures, synergistic toxicity was observed for mixtures of Ni and PHQ, whereas additive toxicity was observed for mixtures of Cd and PHQ. Alone, PHQ had no impact on ROS levels in D. magna. Nickel alone caused elevated ROS, which was further enhanced in the presence of PHQ. Neither Cd nor Cd/PHQ mixtures increased ROS production. Attenuation of toxicity and ROS production was observed in response to treatment with low concentrations of L-ascorbic acid. These results indicate potential toxic interactions between metals and modified PAHs. With redox-active metals, such as Cu and Ni, and modified PAHs, such as PHQ, these interactions can involve ROS formation.
Bioenergetic and pharmacokinetic model for exposure of common loon (Gavia Immer) chicks to methylmercury
Authors: Karasov William H. , Kenow Kevin P. , Meyer Michael W. , Fournier Francois 
Published: June 2007

AbstractA bioenergetics model was used to predict food intake of common loon (Gavia immer) chicks as a function of body mass during development, and a pharmacokinetics model, based on first-order kinetics in a single compartment, was used to predict blood Hg level as a function of food intake rate, food Hg content, body mass, and Hg absorption and elimination. Predictions were tested in captive growing chicks fed trout (Salmo gairdneri) with average MeHg concentrations of 0.02 (control), 0.4, and 1.2 μg/g wet mass (delivered as CH3HgCl). Predicted food intake matched observed intake through 50 d of age but then exceeded observed intake by an amount that grew progressively larger with age, reaching a significant overestimate of 28% by the end of the trial. Respiration in older, nongrowing birds probably was overestimated by using rates measured in younger, growing birds. Close agreement was found between simulations and measured blood Hg, which varied significantly with dietary Hg and age. Although chicks may hatch with different blood Hg levels, their blood level is determined mainly by dietary Hg level beyond approximately two weeks of age. The model also may be useful for predicting Hg levels in adults and in the eggs that they lay, but its accuracy in both chicks and adults needs to be tested in free-living birds.
Removal of cadmium ions during stationary growth phase by an extremely cadmium-resistant strain of Stenotrophomonas sp.
Authors: Chien Chih-Ching , Hung Chun-Wei , Han Chu-Ting 
Published: June 2007

Abstract
Stenotrophomonas sp. CD02 was isolated from a site that previously had been contaminated with high concentrations of the heavy metals cadmium (3 mg kg−1) and chromium (115 mg kg−1). This strain was able to grow on complex (Luria Bertani) medium containing high concentrations of cadmium ion (up to 4 mM). Additionally, it could remove up to 80% of the dissolved ions but only after reaching stationary growth phase. Strain CD02 also tolerated high concentrations of other heavy metals such as chromium, zinc, copper, nickel, and lead at levels more than 2 mM. Although strain CD02 can tolerate much higher cadmium concentrations than the three Stenotrophomonas maltophilia strains tested, they all possess resistance to the same range of antibiotics. This suggests that strain CD02 possesses a mechanism that allows it to tolerate and remove cadmium differently from those conferring resistance to antibiotics. Strain CD02 can be a suitable candidate for heavy metal bioremediation in contaminated environment because it is able to tolerate high concentration of heavy metals and remove cadmium aerobically.
Hazard characterization and identification of a former ammunition site using microarrays, bioassays, and chemical analysis
Authors: Eisentraeger Adolf , Reifferscheid Georg , Dardenne Freddy , Blust Ronny , Schofer Andrea 
Published: June 2007

Abstract
More than 100,000 tons of 2,4,6-trinitrotoluene were produced at the former ammunition site Werk Tanne in Clausthal-Zellerfeld, Germany. The production of explosives and consequent detonation in approximately 1944 by the Allies caused great pollution in this area. Four soil samples and three water samples were taken from this site and characterized by applying chemical-analytical methods and several bioassays. Ecotoxicological test systems, such as the algal growth inhibition assay with Desmodesmus subspicatus, and genotoxicity tests, such as the umu and NM2009 tests, were performed. Also applied were the Ames test, according to International Organization for Standardization 16240, and an Ames fluctuation test. The toxic mode of action was examined using bacterial gene profiling assays with a battery of Escherichia coli strains and with the human liver cell line hepG2 using the PIQOR™ Toxicology cDNA microarray. Additionally, the molecular mechanism of 2,4,6-trinitrotoluene in hepG2 cells was analyzed. The present assessment indicates a danger of pollutant leaching for the soil-groundwater path. A possible impact for human health is discussed, because the groundwater in this area serves as drinking water.
Soil factors controlling the toxicity of copper and zinc to microbial processes in Australian soils
Authors: Broos Kris , Warne Michael St. J. , Heemsbergen Diane A. , Stevens Daryl , Barnes Mary B. , Correll Raymond L. , McLaughlin Mike J. 
Published: June 2007

AbstractTwo soil microbial processes, substrate-induced nitrification (SIN) and substrate-induced respiration (SIR), were measured in the topsoils of 12 Australian field trials that were amended separately with increasing concentrations of ZnSO4 or CuSO4. The median effect concentration (EC50) values for Zn and Cu based on total metal concentrations varied between 107 and 8,298 mg kg−1 for Zn and 108 and 2,155 mg kg−1 Cu among soils. The differences in both Zn and Cu toxicity across the 12 soils were not explained by either the soil solution metal concentrations or CaCl2-extractable metal concentrations, because the variation in the EC50 values was larger than those using total concentrations. Toxicity of Zn and Cu decreased with increasing soil pH for SIN. For Cu, also increasing cation exchange capacity (CEC) and percent clay decreased the toxicity towards SIN. In contrast to SIN, soil pH had no significant effect on toxicity values of SIR. Significant relationships were found between the EC50 values for SIR and background Zn and CEC for Zn, and percent clay and log CEC for Cu. Relationships such as those developed in this study will permit Australian environmental regulation to move from single-value national soil quality guidelines to soil-specific quality guidelines and permit soil-specific risk assessments to be undertaken.