bluuebunny/crossref_metadata_2025_split huggingface dataset:
Tensile Properties of Sn-10Sb-5Cu High Temperature Lead Free Solder
Authors: Zeng Qiulian , Guo Jianjun , Gu Xiaolong , Zhu Qingsheng , Liu Xiaogang 
Published: May 2010

Abstract
The Sn-10Sb-5Cu high temperature lead free solder was developed, and the mechanical property of such bulk solder and the solder joint was investigated in the present work. The microstructure of the Sn-10Sb-5Cu bulk solder was composed of long strip-like Cu6Sn5 and square Sn3Sb2 intermetallic compounds (IMCs). In the solder joint, the IMCs were the same as in the bulk solder but with a much finer microstructure. The test results showed that the tensile properties of the Sn-10Sb-5Cu bulk solder were sensitive to the strain rate. The higher the strain rate, the higher the ultimate strength. The ductility after fracture was enhanced by lowering strain rates. The fracture elongation approached 6.5 % when the strain rate was 10−5/s. Compared with that of the bulk Sn-10Sb-5Cu solder, the tensile strength of the Sn-10Sb-5Cu/Cu solder joint was much lower. The joint showed excellent plasticity with a large nominal engineering strain of 80 % during tensile tests. The tensile strength of the solder joint decreased after some aging time. However, the strength remained at about 80 % of the original value after aging for 15 days at the temperature of 150°C. The difference in the tensile properties between bulk solder and solder joint resulted from the difference in microstructures. Coarser Cu6Sn5 IMC in the bulk solder led to the higher ultimate strength, and the finer Cu6Sn5 IMC in the solder joint resulted in much better fracture ductility of the solder joint.
A Study on the Influence of Measurement Procedures on Suction-Water Content Relationship of a Sandy Soil
Authors: Malaya C. , Sreedeep S. 
Published: May 2010

AbstractSoil suction and its relationship with water content (gravimetric or volumetric) are inevitable in the study of unsaturated soil mechanics. Suction-water content relationship (designated as SWR) is an important input parameter for the mathematical modeling of unsaturated soil response pertained to physico-mechanical, hydraulic, and volume change behavior and hence needs to be accurate and unambiguous. There are two commonly adopted procedures for establishing the SWR. In the first method (designated as continuous measurement), continuous drying suction measurements are performed on the same soil sample, starting from a high water content (corresponding to insignificant suction), which is termed as soil-water characteristic curve. In the second method (designated as spot measurement), remolded soil samples are packed at different compaction states, varying in unit weight and water content, on which suction measurements are performed. It is noted that there is no comparison and critical evaluation of these two procedures adopted for determining SWR. Such a study is important as the particle rearrangement in the soil samples undergoing a drying process might be different from that of the reconstituted/remolded samples. Therefore, the present study attempts to understand the uniqueness of SWR obtained by using two procedures for a locally available sandy soil. In this study, tensiometer and a capacitance probe have been used for measuring suction and volumetric water content, respectively. The study indicates that SWR established by using different procedures may not be unique and there is a need to highlight it while reporting such relationship for the soil.
Development and Evaluation of a Bioenergetics Model for Saugeye
Authors: Zweifel Richard D. , Landis Andrew M. Gascho , Hale R. Scott , Stein Roy A. 
Published: May 2010

AbstractWe parameterized and evaluated a bioenergetics model for saugeye (walleyeSander vitreus× saugerS. canadensis) by using laboratory experiments in an effort to improve predictions of prey consumption. First, we measured daily prey consumption rate and growth of age‐0 and age‐1 saugeyes fed two daily rations (ad libitum and 50% of maximum) at five temperatures ranging from 10°C to 28°C. Additional experiments quantified routine respiration rates and waste losses for three ages of saugeye (ages 0, 1, and 2) at five temperatures ranging from 10°C to 28°C. Mean daily rates of prey consumption (g·g−1·d−1) by saugeyes increased from 10°C to 25°C, declining at 28°C. Respiration rates (g O2·g−1·d−1) increased over the entire range of water temperatures. Waste losses were minor for saugeyes as egestion averaged 3.5% of consumed energy and energy lost via excretion was 4.5% of assimilated energy. We evaluated the accuracy of bioenergetics model predictions of saugeye prey consumption using daily prey consumption and corresponding growth data from our first set of experiments. Model estimates of prey consumption rates (g·g−1·d−1) closely followed observed trends, providing reasonable estimates of cumulative prey consumption across temperature and fish size. The saugeye model provided improved estimates of consumption compared with a model published for walleyes (Kitchell et al. 1977), especially when water temperatures were in excess of 25°C. The differences we observed in predictive performance between the two models resulted from higher thermal optima for saugeyes compared with walleyes, and waste constants for saugeyes were two to three times lower than those calculated from the walleye model. These differences may largely be responsible for the walleye model's overestimation of consumption. Saugeye thermal optima are warmer than those of either parent species, and saugeye is better suited for warm, productive midwestern U.S. reservoirs. The saugeye model developed herein will improve the ability of managers to more accurately predict the consumptive demand of in situ saugeye populations and better tailor stocking rates to match available prey biomass.
Temperature and Salinity Effects on Survival and Growth of Early Life Stage Shubenacadie River Striped Bass
Authors: Cook A. M. , Duston J. , Bradford R. G. 
Published: May 2010

AbstractA series of short, laboratory‐based trials was conducted on striped bass Morone saxatilis from the Shubenacadie River, Nova Scotia, Canada, starting with wild‐caught eggs and proceeding through to the early juvenile stage. The levels of the experimental factors—salinity (0–35‰) and temperature (10–30°C)—spanned the range occurring in the natal estuary. Survival of eggs to 1 d posthatch (dph) was highest, more than 60%, between 2‰ and 20‰ salinity and was reduced significantly (to <50%) only in salinities of 30‰ or greater. Similarly, survival of prefeeding larvae was reduced only at salinities above 30‰, suggesting that their salinity tolerance is higher than that of U.S. populations. Moreover, 1–7‐dph larvae were tolerant to temperature decreases that are lethal to other populations, with around 40% surviving between 10°C and 14°C at intermediate salinities. Older, 23‐dph larvae were less tolerant to cold, with fewer than 20% surviving 7 d at 10°C, but these larvae thrived at high temperature, exhibiting highest survival and growth at 26°C across salinities from 1‰ to 35‰. Growth of early juvenile stages (55–104 dph) was independent of salinity (1–30‰) and was highest between 26°C and 30°C, suggesting a temperature optimum similar to that of U.S. populations.
Sediment and Salmon: The Role of Spawning Sockeye Salmon in Annual Bed Load Transport Characteristics in Small, Interior Streams of British Columbia
Authors: Macdonald J. Stevenson , King Cher A. , Herunter Herb 
Published: May 2010

AbstractThe redd construction process of sockeye salmon Oncorhynchus nerka may be an important and unique component of bed load transport in some northern, interior British Columbia streams. Using pit trap samplers in four streams over 6 years, we examined bed load accumulation and size composition after three distinct periods: spring flood (high flow), salmon spawning (low flow), and winter (low flow). Bed load movement increased with stream velocity and more accumulated during the spring floods than during the winter. However, bed load accumulations were greater during the spawning period than during the winter at similar thalweg velocities. There was a significant influence of spawning fish density on the amount of bed load accumulated. The variability in bed load size composition was most attributable to the tendency for spawners to move proportionally more large material than was moved during the flood and winter periods, with a grain‐size distribution that was comparable to the source material in all but one of the creeks. Mobilization of intermediate‐size material distinguished the spring flood period from the low‐flow winter period but accounted for considerably less of the overall variation. Variability among years was minor. Relative to hydraulic factors, salmon spawning activities have a density‐dependent and unique influence on the mobilization of bed material in interior watersheds. We speculate that there is a positive feedback mechanism by which healthy salmonid stocks contribute to the maintenance of the small stream ecosystems on which they depend.
Accuracy of Using Scales to Age Mixed‐Stock Chinook Salmon of Hatchery Origin
Authors: McNicol Richard E. , MacLellan Shayne E. 
Published: May 2010

AbstractDespite a long history of using scales to age Pacific salmon, there have been few attempts to validate scale‐derived ages. This is particularly true for Chinook salmon Oncorhynchus tshawytscha, a species exhibiting a wide range of life histories across stocks. This has led to continuing questions regarding the accuracy of scale‐based age determination for Chinook salmon. This study assessed the accuracy of Chinook salmon scale age data produced by multiple readers from multiple agencies, who aged hatchery fish of known age from mixed‐stock, nonterminal fisheries conducted along the Pacific coast of Canada from 1991 to 2003. The test sample consisted of scales from 434 fish from both stream‐ and ocean‐type stocks marked with coded wire tags (i.e., fish origin and total age were known). Sample stocks originated from Oregon, Washington, and British Columbia. Five readers from three federal or state Pacific Northwest fisheries agencies participated in the study. The readers possessed various levels of experience, which was classified as (1) deep or shallow (depth) depending on the number of years the reader was involved in aging Chinook salmon scales and (2) broad or narrow (breadth) depending on the variety of stocks the reader had previously encountered. Accuracy ranged from 84% to 94%, although readers with both deep and broad experience consistently achieved accuracies greater than 90%, while those with a narrower breadth of experience tended to show age bias. Overall, the results suggest that aging Chinook salmon scales from ocean‐caught hatchery fish can be accurate and that readers' previous exposure to stocks comprising a wide range of life history types may be at least as important as the number of years of experience in achieving a high level of aging accuracy.
A Simple Biomass‐Based Length‐Cohort Analysis for Estimating Biomass and Fishing Mortality
Authors: Zhang Chang Ik , Megrey Bernard A. 
Published: May 2010

AbstractA biomass‐based length‐cohort analysis (LCA) was examined for its performance in estimating total stock biomass and fishing mortality (F) for a population in equilibrium. We compared two LCA methods—(1) a numbers‐based LCA that relies on catch numbers at length as input data and (2) a new biomass‐based LCA that relies on catch biomass at length—by applying both to simulated data that generally followed characteristics of Pacific chub mackerelScomber japonicusin Korean waters. We investigated the effects of using two length aggregation methods, two data simulation methods, and three expressions of weight growth (i.e., exponential growth over the length increment of the analysis, arithmetic mean growth, and geometric mean growth). Biomass andFwere estimated from the new model and compared with those estimated from the numbers‐based LCA model. A sensitivity analysis was performed to understand which aspect of the model parameters controlled the results. Sensitivity to estimates of terminalFwas also examined. Results of the analysis showed that the allometric power coefficient β was the most important model parameter and that sensitivity of biomass‐based LCA to terminalFwas similar to that of numbers‐based LCA. Monte Carlo simulation was used to evaluate the equilibrium assumption and to calculate confidence intervals for biomass estimates. We applied the biomass‐based LCA model to data for northern rock soleLepidopsetta polyxystrain the eastern Bering Sea. A comparison of biomass‐based LCA population biomass estimates with northern rock sole research survey biomass estimates showed good agreement between the two types of estimates. The biomass‐based LCA described in this study is unique in that it incorporates growth explicitly into the estimation procedure, which can be useful under data‐deficient situations when simple length composition data and estimates of total catch biomass from just one sampling year are the only available data.
Relative Importance of Water Temperature, Water Level, and Lunar Cycle to Migratory Activity in Spawning‐Phase Sea Lampreys in Lake Ontario
Authors: Binder Thomas R. , McLaughlin Robert L. , McDonald D. Gordon 
Published: May 2010

AbstractWe analyzed historical trapping records from six Lake Ontario tributaries to (1) compare the relative importance of water temperature, water level, and lunar cycle to migratory activity in upstream‐migrating sea lampreys Petromyzon marinus and (2) determine whether the relative importance of these variables differs among streams. We found significant stream‐dependent differences in the relative importance of the environmental variables. Water temperature was the best predictor of migratory activity in all six streams. The seasonal distribution of migratory activity was related to mean stream temperature, with an estimated peak migration temperature of approximately 15°C. Changes in stream temperature were equally as important. Migratory activity was stimulated when mean stream temperature increased between consecutive days and was suppressed when mean stream temperature decreased between consecutive days. Water level was a reliable predictor of migratory activity only in the two smallest streams. We hypothesize that high water levels may increase migratory activity in small streams by making them more noticeable. There was no evidence to support either a circumlunar rhythm or gravitational influence on migratory activity. However, because we did not account for cloud cover or the presence of artificial light sources, we cannot exclude the possibility that nighttime light levels influence migratory activity. Our findings provide a set of rules for coarsely projecting migratory activity in upstream‐migrating sea lampreys.
Population Dynamics of Larval Trematodes in Juvenile Bluegills from Three Lakes II, Michigan, and the Potential for Overwinter Parasite‐Induced Host Mortality
Authors: Pracheil Brenda M. , Muzzall Patrick M. 
Published: May 2010

AbstractPrior studies of the population dynamics of larval trematodes infecting juvenile bluegills Lepomis macrochirus have suggested that there may be overwinter loss of the most heavily infected juvenile bluegills from the population. Our study objectives were to (1) describe population dynamics of the four most common larval trematodes—Cryptogonimus sp., Posthodiplostomum minimum, Diplostomum sp., and Neascus sp.—and the overall larval trematode burden for three year‐classes of juvenile bluegills in Three Lakes II, Michigan; and (2) assess the potential for larval trematode infections as a cause of first‐winter bluegill mortality based on changes in parasite overdispersion. We examined 393 juvenile bluegills for larval trematodes, and more than 99% of examined bluegills were infected with a parasite. Decreases in overdispersion of several larval trematode species in spring and summer 2003 may have been the result of larval trematode‐induced host mortality. The results of this study suggest that heavy larval trematode infections may be negatively influencing bluegill survival, particularly during and after winter. Additionally, this study demonstrates that population dynamics of larval trematodes in Three Lakes II are similar to those of trematodes found in the southeastern USA but that the larval trematodes in the present study may have a more negative effect on bluegill survival due to more harsh winter conditions.
Tail‐Beat Patterns in Dual‐Frequency Identification Sonar Echograms and their Potential Use for Species Identification and Bioenergetics Studies
Authors: Mueller Anna‐Maria , Burwen Deborah L. , Boswell Kevin M. , Mulligan Tim 
Published: May 2010

AbstractWe observed patterns in echograms of data collected with a dual‐frequency identification sonar (DIDSON) that were related to the tail beats of fish. These patterns reflect the size, shape, and swimming motion of the fish and also depend on the fish's angle relative to the axis of the beam. When the tail is large enough to reflect sound of sufficient intensity and the body is angled such that the tail beat produces periodic changes in the range extent covered by the fish image, then the tail beat becomes clearly visible on echograms that plot the intensity maximum of all beams. The analysis of DIDSON echograms of a mix of upstream‐migrating Chinook salmon Oncorhynchus tshawytscha and sockeye salmon O. nerka resulted in the separation of two groups: (1) fish of sockeye salmon size that swam with a tail‐beat frequency (TBF) between 2.0 and 3.5 beats/s and (2) fish of Chinook salmon size with a TBF between 1.0 and 2.0 beats/s. There was no correlation between TBF and fish size within each group, which suggests that the observed difference in TBF between the two groups was species‐specific rather than an indirect effect of the groups' difference in size. The technique of extracting TBF from DIDSON echograms may also be useful for bioenergetics studies. Compared with electromyogram telemetry, it offers the advantages of being nonintrusive and faster to set up and analyze and therefore is suitable for analyzing larger sample sizes. The disadvantages are that the technique's potential is limited to relatively large fish, it can cover only relatively small areas, it cannot be used to follow individual fish over long distances, and some environments are too noisy to produce DIDSON images of sufficient quality.
Do Nonnative Salmonines Exhibit Greater Density and Production than the Natives They Replace? A Comparison of Nonnative Brook Trout with Native Cutthroat Trout
Authors: Benjamin Joseph R. , Baxter Colden V. 
Published: May 2010

AbstractThe replacement of native species by nonnative species has been widely documented. In aquatic ecosystems, nonnative trout often replace native trout species to which they are closely related. For example, nonnative brook trout Salvelinus fontinalis have replaced native cutthroat trout Oncorhynchus clarkii throughout western North America. We hypothesized that when brook trout replace cutthroat trout, they exhibit greater density, biomass, and annual production than were achieved by the cutthroat trout before replacement. We tested this hypothesis in five paired streams in the Teton River drainage, Idaho, over a 4‐year period. Streams were paired based on similar habitat characteristics and the presence of brook trout or cutthroat trout as the dominant species. Fish were surveyed annually by means of multipass depletion along representative stream reaches. Consistent with our hypothesis, brook trout exhibited 2.4 times greater density, 1.7 times greater biomass, and 2.5 times higher annual production than cutthroat trout. Because age‐0 fish were difficult to capture during electrofishing, we also analyzed the data without this age‐class. When age‐0 fish were excluded, brook trout exhibited 1.3, 1.6, and 2.1 times greater density, biomass, and annual production, respectively, than cutthrout trout. These results are consistent with the hypothesis that nonnative salmonines exhibit greater density and production than the native fishes they replace, though the generality of this finding remains to be tested. The differences that we observed not only testify to the success of brook trout as an introduced species in western North America but also point to likely changes in ecosystem function that may accompany their replacement of native cutthroat trout.
Identification of Marine‐Derived Lipids in Juvenile Coho Salmon and Aquatic Insects through Fatty Acid Analysis
Authors: Heintz Ron A. , Wipfli Mark S. , Hudson John P. 
Published: May 2010

AbstractThe energetic benefits enjoyed by consumers in streams with salmon runs depend on how those benefits are accrued. Adult Pacific salmon Oncorhynchus spp. deliver significant amounts of nutrients (i.e., nitrogen and phosphorus) and carbon to streams when they spawn and die; these nutrient additions can have demonstrable effects on primary production in streams. Consumption of carcass tissues or eggs provides for direct energy subsidies to consumers and may have significant effects on their condition. In this study, comparisons of juvenile coho salmon O. kisutch and aquatic insects exposed to terrestrial and marine energy sources demonstrated that direct consumption of marine‐derived lipids had a significant effect on the lipid reserves of consumers. Direct consumption of marine‐derived tissues was verified through fatty acid analysis. Selected aquatic insects and juvenile coho salmon were reared for 6 weeks in experimental streams supplied with terrestrial or marine energy sources. Chironomid midges, nemourid stoneflies, and juvenile coho salmon exposed to the marine energy source altered their fatty acid compositions by incorporating the long‐chain polyunsaturated fatty acids that are characteristic of marine fish. The fatty acid composition of baetid mayflies was unaffected. The direct movement of specific fatty markers indicated that direct consumption of marine‐derived tissues led to increased energy reserves (triacylglycerols) in consumers. Similar results were obtained for juvenile coho salmon sampled from natural streams before and after the arrival of adult salmon runs. These data indicate that marine‐derived lipids from anadromous fish runs are an important source of reserve lipids for consumers that overwinter in streams.