bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of Diet and Strain on Growth and Performance in Hybrid Bluegills
Authors: Stinefelt Beth M , Eya Jonathan C , Semmens Kenneth J , Blemings Kenneth P 
Published: September 2006

Abstract
Little is known about the diets and genetic strains that are optimal for the production of hybrids of bluegill Lepomis macrochirus. The objective of this study was to determine whether there are differences in feed, nitrogen and amino acid conversion, lipid deposition, liver lysine oxidation, and liver glycogen in two such hybrids—Georgia Giant (GG, a proprietary strain of hybrid bluegill) and a commercial hybrid bluegill (CHBG, green sunfish L. cyanellus × bluegill)—fed five commercially available diets. The diets were formulated to the following minimum crude protein (CP)–fat ratios: 32/3, 38/8, 40/10, 42/16, and 45/20. Fish were randomly allotted to 20 tanks, with two tanks per diet within each strain. After 12 weeks in experimental conditions, GGs had higher feed intake (P &lt; 0.001), higher weight gain (P &lt; 0.001), better feed conversion (P &lt; 0.05), and lower liver glycogen (P &lt; 0.05) than CHBG. Liver lysine oxidation and whole-body lipid deposition was not significantly different between strains. Consumption of the 42/16 diet resulted in increased growth, a better feed conversion (P &lt; 0.05), and a better retention of specific amino acids than all other diets, regardless of strain. Diet composition did not result in significant differences in liver lysine oxidation, liver glycogen, and lipid deposition, regardless of strain. These data demonstrate that genetic strain and diet have important impacts on bluegill production and that the most nutrient-dense diets do not necessarily lead to enhanced performance relative to diets of lower CP and fat.
Rapid and Slow Sand Filtration Techniques and Their Efficacy at Filtering Triactinomyxons of Myxobolus cerebralis from Contaminated Water
Authors: Arndt Ronney E , Wagner Eric J 
Published: September 2006

Abstract
Slow and rapid sand filtration methods were tested for their ability to remove triactinomyxon actinospores (Tams), the waterborne infective stage of the salmonid parasite Myxobolus cerebralis, from contaminated water. Within the rapid sand filtration treatments, two backflush protocols were tested. The first consisted of extended backflush duration, and the second consisted of diverted flow past the aquaria with fish for 5 min after backflushing. A slow sand filter treatment served as a nonbackflushed control to the two rapid sand filters and also as its own unique filtration technique. Negative and positive controls were run simultaneously and served both slow and rapid sand filters. The sand used consisted only of particles greater than 180 μm (diameter). Triactinomyxon actinospores were regularly introduced to the fish-rearing systems above the sand filters. After 60 d, clinical signs of whirling behavior and black tails were seen among the positive controls. A polymerase chain reaction (PCR) assay for M. cerebralis conducted at the study's conclusion indicated no infection among the negative controls and both of the rapid sand filter treatments. In the slow sand filter treatment 1.6% of all fish were infected, whereas 98% of the positive controls were infected. Portions of the same tissue samples used for the PCR analysis were also assayed according to the pepsin–trypsin digest (PTD) test. Within the rapid sand filters, 2.9% of fish within the long back flush treatment were infected, as were 100% of the positive controls. The diverted backflush, slow sand filter, and negative controls were all negative according to the PTD test. These results demonstrate that the backflush technique is important in the proper function of rapid sand filters used to remove Tams and that both rapid and slow sand filtration could be viable options in treating hatchery water supplies that are contaminated with whirling disease.
Safer High-Density Polyethylene Plastic Paddles for Hatching Channel Catfish Eggs
Authors: Steeby James A , Nobile Jerry , Wright Wayne 
Published: September 2006

Abstract
A new paddle made from high-density polyethylene plastic has been devised for use in egg hatching troughs. This paddle is very safe as it will paddle properly through water and can be stopped easily when grabbed by hand. The plastic used to fabricate this paddle is 1/8 inch thick and cut from a drum with a reciprocating saw. New 30-gal drums, made of food-grade federally approved high-density polyethylene can be purchased for about US$30.
The Effect of Hatchery Spawning Protocols on Coho Salmon Return Timing in the Cowlitz River, Washington
Authors: Tipping Jack M , Busack Craig A 
Published: September 2006

Abstract
We compared the pre- and posthatchery return times of adult coho salmon Oncorhynchus kisutch on the Cowlitz River, Washington, after 30 years of hatchery operation. In addition, at the Cowlitz Salmon Hatchery in fall 1998, 1999, and 2000, we differentially tagged juveniles for release in 1999, 2000, and 2001 that were produced from broodstock originating from early (August to mid-October), middle (mid-October through November), and late (December and thereafter) time arrival windows to determine the fidelity of adult return time distribution to the window of origin. We found that posthatchery mean and median coho salmon adult return times were delayed about 2 weeks compared with prehatchery conditions, that October–November returns increased from 46% to 81% after hatchery operation, that a mean of 57% of 3-year-old adult fish returned in the return time window of origin, and that many of the early- and late-origin fish returned in the middle time period. A mean of 70.4% of 2-year-old jacks from all releases returned in the middle return window. Much of the increase in October–November returns was probably due to a hatchery production emphasis of the middle-returning fish. We recommend that broodstock be accumulated at historically proportional rates with respect to run timing, which may require additional adult holding ponds at the hatchery.
The Effect of Juvenile Rearing Density on Adult Returns of Summer Steelhead
Authors: Tipping Jack M , Byrne James B , Hillson Todd D 
Published: September 2006

Abstract
Juvenile steelhead Oncorhynchus mykiss were reared at two hatcheries in an attempt to determine the influence of loading (kg · L−1 · min−1) and density (kg/m3) on adult survival. At one hatchery in which fish were reared and released from raceways for 3 years, there was no significant difference in recovery rates of fish reared at levels 20% below normal loadings and densities compared with those reared at 20% above normal loadings and densities. At a second hatchery in which fish were reared in ponds for 3 years before release, flows were adjusted so that loadings were similar but densities differed; a significant decrease was observed in returns of test fish when loading was 2.1 kg · L−1 · min−1 and density was 5.8 kg/m3, and returns greatly decreased when test fish loading was 2.3 kg · L−1 · min−1 and density was 6.3 kg/m3.
Evaluation of 36%-Protein Diets with or without Animal Protein for Rearing Tank-Hatched Golden Shiner Fry in Ponds
Authors: Lochmann Rebecca , Stone Nathan , Phillips Harold , Bodary Melinda 
Published: September 2006

Abstract
The objective of this study was to determine whether fry of golden shiners Notemigonus crysoleucas reared in ponds differed with respect to growth, survival, feed conversion, total yield, condition, and response to low dissolved oxygen when fed a practical diet of 36% protein from animal and plant sources (five ponds) versus a diet of only plant sources (six ponds). Newly hatched fry (1 mg) were stocked at 2.5 × 106/ha in 12 fertilized ponds (0.04 ha each). Fish were fed twice daily at a rate of 8.0–15.9 kg/ha for 12 weeks. Chlorophyll a was not different between diets, indicating that natural food production in ponds was similar between treatments. Between-treatment differences in average individual weight (0.56–0.59 g), relative weight (114.4– 115.6), Fulton's condition index (K = 0.88), total yield (40.8–45.6 kg), feed conversion (0.85– 0.95), and survival (75.9–79.2%) were not significant. Postharvest survival of fish exposed to low dissolved oxygen at 20°C in a laboratory test was not affected by diet. These results indicate that diets with all plant protein sources are suitable for raising golden shiners in fertilized ponds from first-feeding fry to small juveniles.
Comparison of Hatchery Performance Attributes among Three Strains of Age-0 Coaster Brook Trout
Authors: Volkman Eric T , Pangle Kevin L , Rajchel Deborah A , Sutton Trent M , Bast Dale R 
Published: September 2006

Abstract
The hatchery performance attributes of three strains (Lake Nipigon [Nipigon], Siskiwit Bay [Siskiwit], and Tobin Harbor [Tobin]) of fingerling coaster brook trout Salvelinus fontinalis were compared during a 12-week laboratory experiment. Despite similar initial sizes, the final mean length and weight of Nipigon fish (94.1 mm and 9.9 g) were significantly greater than those of the Siskiwit (86.7 mm and 7.7 g) and Tobin (90.4 mm and 7.2 g) strains. There were no differences in mean specific growth rates in length and weight or mean daily growth rate in length among the strains. However, there was a difference in the mean daily absolute growth rate in weight, the Nipigon and Siskiwit strains (0.10%/d and 0.08%/d, respectively) displaying a greater rate of growth than Tobin Harbor (0.07%/d) fish. Mean survival rates (range = 97–98%) and relative weights (range = 100.1–101.1 g) did not differ significantly among the three strains. Based on our results, we recommend that these strains of fingerling coaster brook trout be reared similarly in hatchery environments and that strain selection for rehabilitation stocking purposes consider hatchery residence time and the natural genetic variation of the source population of broodstock fish.
Accounting for Demographic and Environmental Stochasticity, Observation Error, and Parameter Uncertainty in Fish Population Dynamics Models
Authors: Newman Ken B. , Lindley Steven T. 
Published: September 2006

Abstract
Bayesian hierarchical state-space models are a means of modeling fish population dynamics while accounting for both demographic and environmental stochasticity, observation noise, and parameter uncertainty. Sequential importance sampling can be used to generate posterior distributions for parameters, unobserved states, and random effects for population models with realistic dynamics and error distributions. Such a state-space model was fit to the Sacramento River winter-run Chinook salmon Oncorhynchus tshawytscha population, where a key objective was to develop a tool for predicting juvenile out-migration based on multiple sources of data. One-year-ahead 90% prediction intervals based on 1992−2003 data, while relatively wide, did include the estimated values for 2004. Parameter estimates for the juvenile production function based on the state-space model formulation differed appreciably from Bayesian estimates that ignored autocorrelation and observation noise.
Ontogenetic Trophic Interactions and Benthopelagic Coupling in Lake Washington: Evidence from Stable Isotopes and Diet Analysis
Authors: McIntyre J. K. , Beauchamp D. A. , Mazur M. M. , Overman N. C. 
Published: September 2006

AbstractStable isotopes of nitrogen and carbon and stomach content analysis were used to determine the trophic position and relative importance of benthic and pelagic pathways for different life stages and species of the major fishes and invertebrate prey in Lake Washington. Significant coupling of the benthic and pelagic pathways was evident in this complex food web across seasons and fish ontogenies. Among apex predators, cutthroat trout Oncorhynchus clarkii and northern pikeminnow Ptychocheilus oregonensis shifted ontogenetically from benthic omnivory to pelagic piscivory, whereas yellow perch Perca flavescens shifted from pelagic zooplanktivory to benthic piscivory. Apex predators continued to rely on benthic prey seasonally, particularly in winter and spring. Benthic pathways were less important to the current diets of apex predators than they were during the recovery from eutrophication in the 1970s. Surprisingly, the δ15N values for copepods during winter and for zooplanktivorous longfin smelt Spirinchus thaleichthys and threespine sticklebacks Gasterosteus aculeatus were similar to those for top piscivores, whereas the significantly lower values for zooplanktivorous juvenile sockeye salmon O. nerka were more similar to expectations. Nitrogen and carbon isotope ratios of pelagic planktivores and invertebrates also varied seasonally. Mixing model results showed that stable isotopes and stomach contents were comparable for determining ontogenetic trends, but stable isotopes established these trends with many fewer samples and less variability and accurately portrayed ontogenetic trends when few stomach samples were available. However, stomach content analysis was critical in delineating seasonal trends in diets and for identifying specific prey species.
Status of Yellowstone Cutthroat Trout in Idaho
Authors: Meyer Kevin A. , Schill Daniel J. , Lamansky James A. , Campbell Matthew R. , Kozfkay Christine C. 
Published: September 2006

AbstractIn this study, we electrofished 961 study sites to estimate the abundance of trout (in streams only) throughout the upper Snake River basin in Idaho (and portions of adjacent states) to determine the current status of Yellowstone cutthroat troutOncorhynchus clarkii bouvieriiand other nonnative salmonids and to assess introgressive hybridization between Yellowstone cutthroat trout and rainbow troutO. mykiss. Yellowstone cutthroat trout were the most widely distributed species of trout, followed by brook troutSalvelinus fontinalis, rainbow trout and rainbow trout × Yellowstone cutthroat trout hybrids, and brown troutSalmo trutta. Of the 457 sites that contained Yellowstone cutthroat trout, less than half also contained nonnative salmonids and only 88 contained rainbow trout and hybrids. In the 11 geographic management units (GMUs) for which sample size permitted abundance estimates, the number of 100‐mm and larger trout was estimated to be about 2.2 ± 1.2 million (mean ± confidence interval); of these, about 1.0 ± 0.4 million were Yellowstone cutthroat trout. Similarly, the estimated abundance of trout smaller than 100 mm was 2.0 ± 1.4 million, of which about 1.2 ± 0.7 million) were Yellowstone cutthroat trout. Both estimates are almost certainly biased downward owing to methodological constraints. Yellowstone cutthroat trout were divided into approximately 70 subpopulations, but estimates could be made for only 55 subpopulations; of these, 44 and 28 subpopulations contained more than 1,000 and 2,500 Yellowstone cutthroat trout, respectively. We compared morphological assessments of purity with subsequent molecular DNA analysis from 51 of the study sites and found that levels of purity were positively correlated between methods (r= 0.84). Based on this agreement, we classified Yellowstone cutthroat trout (based on morphological characteristics alone) as pure at 81% of the study sites within these GMUs. Our results suggest that despite the presence of nonnative threats (genetic and competitive), Yellowstone cutthroat trout remain widely distributed and appear to have healthy populations in numerous river drainages in Idaho.
Spatial Variation in Brown Trout Production: The Role of Environmental Factors
Authors: Almodóvar Ana , Nicola Graciela G. , Elvira Benigno 
Published: September 2006

AbstractSpatial variation in Spanish populations of brown troutSalmo truttawas studied in 10 streams of contrasting environmental and biological characteristics based on data compiled over 7 years (1992–1998). Three of the streams had soft water (mean alkalinity as CaCO3= 19.3 mg/L) supplied by granite catchments at elevations around 1,250 m above sea level and had a low abundance of macroinvertebrates (mean density = 598 individuals/m2; mean biomass = 0.63 g/m2). The remaining streams had hard water (mean alkalinity = 253.6 mg/L) flowing over limestone at 850–1,400‐m elevations and possessed a greater benthic faunal abundance (mean density = 2,433 individuals/m2; mean biomass = 2.76 g/m2). Mean brown trout population characters varied significantly throughout the study area (density = 1,567–5,594 fish/ha; biomass = 56.6–240.2 kg/ha; annual production = 47.0–182.0 kg/ha, and the ratio of annual production to mean biomass = 1.01–1.56). A stepwise multiple regression analysis revealed a significant relationship between brown trout production and chemical features indicative of high water productivity, which accounted for 61% of the variance explained by the model. A broader spatial analysis, based on a review of the available European work, corroborated that annual brown trout production in streams flowing over limestone bedrock was greater (mean = 121.6 kg/ha; range = 30.0–253.3 kg/ha) than that in streams flowing over siliceous bedrock (mean = 76.6 kg/ha; range = 3.5–234.0 kg/ha). Data from brown trout populations throughout Europe showed a significant positive correlation between production and alkalinity according to the model log10(production) = 1.41 + 0.31·log10(alkalinity), which explained 53% of the variance. Our findings support previous evidence on the influence of water fertility on salmonid production and expand knowledge of the factors that influence brown trout production within the native range of the species.
Optimal control of a two-stage reactor system
Authors: Hirmajer T. , Fikar M. 
Published: September 2006

AbstractOptimal operation policies were investigated for a batch reactor system with two different operation stages. At the end of the first nonisothermal stage one of the reactants was added. Since that moment the reactor was operated isothermally. In each stage behavior of the reactor was described by a set of differential equations. The maximum conversion problem was investigated subject to various operating constraints. Dynamic optimization based on the control vector parametrization was used to find the optimal control profile. Gradients of the resulting nonlinear programming problem were obtained by adjoint method based on the optimal control theory.
Children's narrative memory for accidents and their post‐traumatic distress
Authors: O'Kearney Richard , Speyer Joanne , Kenardy Justin 
Published: September 2006

AbstractThis study examines how the quality of children's memory for a traumatic event is related to trauma‐related distress and adjustment. Four to 7 weeks after an accident requiring hospitalisation, 80 children aged 7–16 were asked to provide a narrative memory of the event. Age and the quality of the memory report based on its lexical and cohesive structure accounted for a significant and sizable proportion of the variability in the children's intrusive symptoms about the event after considering trauma severity and the child's language ability and gender. There was no significant relationship between memory quality and event specific avoidant symptoms. Children who were troubled by intrusive symptoms at 4 to 7 weeks continue to seek personal control and mastery by cognitively making sense of their experiences. The study's implications for understanding the process of children's adaptation to such events and for the development of chronic problematic adjustment are discussed. Copyright © 2006 John Wiley & Sons, Ltd.
Yield Functions for Porous Materials with Cubic Symmetry Using Different Definitions of Yield
Authors: McElwain D. L. S. , Roberts A. P. , Wilkins A. H. 
Published: September 2006

AbstractPlastic yield criteria for porous ductile materials are explored numerically using the finite‐element technique. The cases of spherical voids arranged in simple cubic, body‐centred cubic and face‐centred cubic arrays are investigated with void volume fractions ranging from 2 % through to the percolation limit (over 90 %). Arbitrary triaxial macroscopic stress states and two definitions of yield are explored. The numerical data demonstrates that the yield criteria depend linearly on the determinant of the macroscopic stress tensor for the case of simple‐cubic and body‐centred cubic arrays – in contrast to the famous Gurson‐Tvergaard‐Needleman (GTN) formula – while there is no such dependence for face‐centred cubic arrays within the accuracy of the finite‐element discretisation. The data are well fit by a simple extension of the GTN formula which is valid for all void volume fractions, with yield‐function convexity constraining the form of the extension in terms of parameters in the original formula. Simple cubic structures are more resistant to shear, while body‐centred and face‐centred structures are more resistant to hydrostatic pressure. The two yield surfaces corresponding to the two definitions of yield are not related by a simple scaling.
Iron Based Cellular Structures – Status and Prospects
Authors: Stephani G. , Andersen O. , Göhler H. , Kostmann C. , Kümmel K. , Quadbeck P. , Reinfried M. , Studnitzky T. , Waag U. 
Published: September 2006

AbstractCellular metals based on iron have been intensively investigated during the last two decades. Because of the significant decrease in of the structural density of iron based cellular structures, numerous technologies have been developed for their manufacturing. Besides the tremendous weight reduction a combination with other properties like energy and noise absorption, heat insulation and mechanical damping can be achieved. This contribution will give an overview about the latest state in iron based cellular materials, including technologies in manufacturing, properties and potential applications.
Characterization and Mechanical Behavior of Nanoporous Gold
Authors: Hodge A. M. , Hayes J. R. , Caro J. A. , Biener J. , Hamza A. V. 
Published: September 2006

AbstractHere we present current issues in understanding the mechanical behavior of nanoporous foams as a new class of high yield strength / low density materials. Gold nanoporous foams are used for a systematic study of mechanical properties since they can be synthesized with a wide range of ligaments sizes and densities. Preliminary tests demonstrate that a) Au foams have a fracture behavior dictated by the ligament size, and b) nanoporous Au is a high yield strength material.
Elastic Response of Titanium Foams During Compression Tests and Using Laser‐Ultrasonic Probing
Authors: Lefebvre L.‐P. , Blouin A. , Rochon S.‐M. , Bureau M. N. 
Published: September 2006

AbstractThis paper presents an evaluation of the elastic properties of titanium foams by two methods: the evaluation of the unloading slopes measured during destructive compression tests and the measurements of the resonance frequencies of foams using laser‐ultrasonics. The results show that the elastic moduli evolve during the compression tests. The values extrapolated at zero deformation can be used to determine the elastic properties of undeformed specimens. Besides, laser‐ultrasonic techniques can be used to bring foam specimens into resonance and to measure the elastic modulus and Poisson's ratio. The values measured by the two methods are in good agreement.