bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mechanisms of cesium sorption onto magnetite
Authors: Granizo Noelia , Missana T. 
Published: November 2006

One of the current options for the final disposal of high level radioactive wastes is the deep geological repository (DGR). The metal canisters represent the first physical barrier to radionuclide migration towards the geosphere and their corrosion products may play a significant role in sequestering radionuclides by sorption and/or (co)precipitation phenomena.
In this work, the sorption of 137Cs on pure nanocrystalline magnetite has been experimentally studied in a wide range of pH, ionic strength, and radionuclide and sorbent concentration. The magnetite was synthesized in laboratory under controlled conditions and its main physico-chemical properties as microstructure, surface area and surface charge were analysed previous to sorption experiments.
Sorption was negligible up to pH 8.5 and maximum sorption values were reached around pH 12. A significant increase in Cs sorption was observed when decreasing the ionic strength. Linear sorption isotherms were observed within the range of Cs concentration used (up to 10-6 M).
As expected, Cs showed very small sorption onto the oxide, but the whole experimental results could be satisfactorily fit with a simple model. In addition, the model developed in the oxide-electrolyte system was able to reproduce fairly well the sorption of Cs onto magnetite in two more complex waters (synthetic bentonite and cement porewaters).
All the possible effects on sorption that could increase the uncertainties on the (small) sorption values were analysed in depth. In addition, the possible influence of mineral trace impurities on the sorption (for example silicates from experimental vessels), already discussed in the literature, was avoided.
Fish Entrainment into Irrigation Canals: An Analytical Approach and Application to the Bow River, Alberta, Canada
Authors: Post John R. , Poorten Brett T. , Rhodes Trevor , Askey Paul , Paul Andrew 
Published: November 2006

Abstract
The Carseland Canal on the Bow River, Alberta, diverted water at a rate of 1.4–37.7 m3/s during the 2003 irrigation season. We estimated daily entrainment rates of rainbow trout Oncorhynchus mykiss, brown trout Salmo trutta, and mountain whitefish Prosopium williamsoni throughout the diversion season using population assessments of fish in the Bow River and the irrigation canal coupled to an estimate of the evacuation rate of intentionally entrained fish. Total entrainment during the irrigation season was estimated at 3,996 rainbow trout, 664 brown trout, and 2,352 mountain whitefish. Large fish (&gt;150 mm fork length [FL]) made up 42.0% of the total number of entrained rainbow trout, 17.0% of entrained brown trout, and 0.5% of entrained mountain whitefish, representing 1.1, 0.8, and 0.3% of the total mortality observed in these Bow River populations. Earlier estimates of canal losses based on fall rescues of fish suggest that entrainment varies annually and that the 2003 estimates were low for rainbow trout and brown trout and high for mountain whitefish. We also identified 11 additional species that were either entrained or resident in the system within the canal and associated settling pond.
Evaluation of an Unsuccessful Brook Trout Electrofishing Removal Project in a Small Rocky Mountain Stream
Authors: Meyer Kevin A. , Lamansky James A. , Schill Daniel J. 
Published: November 2006

Abstract
In the western United States, exotic brook trout Salvelinus fontinalis frequently have a deleterious effect on native salmonids, and biologists often attempt to remove brook trout from streams by means of electrofishing. Although the success of such projects typically is low, few studies have assessed the underlying mechanisms of failure, especially in terms of compensatory responses. A multiagency watershed advisory group (WAG) conducted a 3-year removal project to reduce brook trout and enhance native salmonids in 7.8 km of a southwestern Idaho stream. We evaluated the costs and success of their project in suppressing brook trout and looked for brook trout compensatory responses, such as decreased natural mortality, increased growth, increased fecundity at length, and earlier maturation. The total number of brook trout removed was 1,401 in 1998, 1,241 in 1999, and 890 in 2000; removal constituted an estimated 88% of the total number of brook trout in the stream in 1999 and 79% in 2000. Although abundance of age-1 and older brook trout declined slightly during and after the removals, abundance of age-0 brook trout increased 789% in the entire stream 2 years after the removals ceased. Total annual survival rate for age-2 and older brook trout did not decrease during the removals, and the removals failed to produce an increase in the abundance of native redband trout Oncorhynchus mykiss gairdneri. Lack of a meaningful decline and unchanged total mortality for older brook trout during the removals suggest that a compensatory response occurred in the brook trout population via reduced natural mortality, which offset the removal of large numbers of brook trout. Although we applaud WAG personnel for their goal of enhancing native salmonids by suppressing brook trout via electrofishing removal, we conclude that their efforts were unsuccessful and suggest that similar future projects elsewhere over such large stream lengths would be costly, quixotic enterprises.
Managing a Migratory Pest Species: A Selective Trap for Common Carp
Authors: Stuart Ivor G. , Williams Alan , McKenzie John , Holt Terry 
Published: November 2006

Abstract
Trapped common carp Cyprinus carpio display a pronounced escape behavior of jumping out of the water; this behavior is not exhibited by most Australian native fishes. Hence, there appears to be an important opportunity to exploit the unique jumping behavior of nonnative common carp to aid selective removal. We report on the Williams cage, a simple device that automatically separates jumping common carp from nonjumping fish. Between November 2002 and April 2005, the Williams cage was tested at Torrumbarry Weir fishway on the Murray River, Victoria, Australia, and trapped fish were counted every 24 h. The Williams cage successfully separated 88% of adult common carp into a confinement area. In contrast, more than 99.9% of 8,031 native fish passed through the Williams cage and exited the fishway. The Williams cage may provide a method for controlling dispersal and abundance of common carp and may be applicable to other nuisance fish species.
Effectiveness of a Plastic Mesh Substrate Cover for Reducing the Effects of Common Carp on Aquatic Ecosystems
Authors: Parkos Joseph J. , Santucci Victor J. , Wahl David H. 
Published: November 2006

Abstract
A great deal of effort has been directed at eliminating or controlling common carp Cyprinus carpio populations, but these efforts have had limited success. We assessed the effectiveness of an alternative approach, using plastic-mesh substrate covers, to reduce environmental effects of common carp, Multiple trophic levels were monitored in 0.06-ha enclosures in experimental ponds that contained either common carp with mesh covers, common carp with no mesh covers, no common carp with mesh covers, or neither fish nor mesh covers. Macroinvertebrates and macrophytes were also sampled over a 1-year period in six field sites with paired mesh cover and control plots. Common carp significantly increased turbidity (NTU) and total phosphorus (μg/L), decreased macrophyte cover (%), altered the relative abundance of zooplankton taxa (N/L), and suppressed macroinvertebrate abundance (N/m2) in ponds. In contrast, carp did not significantly affect either total nitrogen (μg/L) or phytoplankton (μg/L) concentrations. Mesh substrate covers did not significantly reduce any effects of common carp in the pond enclosures. Abundances of macroinvertebrates and macrophytes also did not differ between field plots with and without mesh covers. The lack of effective reduction of common carp-induced effects limits the usefulness of mesh substrate covers as a tool for habitat restoration.
Diet and Bioenergetics of Lake‐Rearing Juvenile Chinook Salmon in Lake Washington
Authors: Koehler Michele E. , Fresh Kurt L. , Beauchamp David A. , Cordell Jeffery R. , Simenstad Charles A. , Seiler David E. 
Published: November 2006

AbstractUse of lake habitats by ocean‐type Chinook salmonOncorhynchus tshawytschais rare under natural conditions. We studied aspects of the trophic ecology of naturally and hatchery‐produced juvenile Chinook salmon rearing in the littoral zone of highly urbanized Lake Washington in Washington State. During February through May, naturally produced juvenile Chinook salmon occupied littoral habitats and consumed mostly epibenthic prey, primarily chironomid pupae (Diptera). In June, they switched to a diet dominated by plankton, specificallyDaphniaspp. This diet shift from littoral prey to limnetic prey coincided with increasing temperature, a shift by the fish from littoral to limnetic habitats, the spring bloom ofDaphnia, and increasing fish size. Bioenergetics modeling for these populations estimated that naturally produced juvenile Chinook salmon had high consumption rates and were generally feeding close to their maximum ration, even after large numbers of hatchery‐produced Chinook salmon entered the lake. The feeding rates, growth rates, and proportions of maximum daily ration from the modeling suggested that under current conditions, both naturally produced and hatchery‐produced juvenile Chinook salmon were finding ample food in littoral habitats of Lake Washington. These results further reveal that hatchery‐produced Chinook salmon did not compete with naturally produced fish and that this was probably a result of hatchery juveniles entering the lake during the springDaphniabloom when this prey is abundant. Our results suggest that managers should focus Chinook salmon recovery efforts in the Lake Washington basin on other aspects of the species' lake use, such as predation or disease, or on other life stages (e.g., spawning adults).
Poststocking Movements and Habitat Use of Hatchery‐Reared Juvenile Pallid Sturgeon in the Missouri River below Fort Randall Dam, South Dakota and Nebraska
Authors: Jordan George R. , Klumb Robert A. , Wanner Greg A. , Stancill Wayne J. 
Published: November 2006

AbstractTelemetry was used to evaluate seasonal and diel movement patterns, general habitat use, survival, and spatial distributions of hatchery‐reared juvenile pallid sturgeon Scaphirhynchus albus stocked in the Missouri River below Fort Randall Dam, South Dakota and Nebraska. Sampling occurred at about 2‐week intervals during spring through fall. Of 22 ultrasonically tagged fish, 13 were intensively followed to assess hourly diel movement rates. A total of 258 relocations were made for the 22 tagged fish; 19 fish were relocated at least once, and 16 were relocated multiple times. At least 68% of tagged fish survived for 2.5 years. In 2000, fish were found mainly upstream of the stocking site, whereas in 2001 and 2002 the entire reach was used. Juveniles were found primarily in the main channel at depths exceeding 80% of the maximum channel cross‐section depth, where bottom current velocities ranged from 0.1 to 0.9 m/s. Clusters of juvenile pallid sturgeon (i.e., two or more fish) within 750 m of each other were observed on 15 dates, and clusters of juveniles within 500 m of each other were observed on 10 dates. Clusters were observed during all seasons. Mean (±2 SE) range of movement was significantly less in 2000 (8.3 ± 5.8 km) than in 2001 (29.3 ± 8.8 km) and 2002 (28.9 ± 15.0 km). We detected no significant differences in movement rates among years, seasons, or diel periods (i.e., dawn, daytime, dusk, and night). Our study indicates that range of movements of juvenile pallid sturgeon based on shorter studies (i.e., ≤1 year) should be interpreted cautiously because hatchery‐reared fish may not have acclimated to the riverine environment until the second year after stocking. Based on survival and distribution of juvenile pallid sturgeon throughout the study area, we conclude that this reach is suitable for recovery efforts.
Effect of Discharge on Daytime Habitat Use and Selection by Muskellunge in the New River, Virginia
Authors: Brenden Travis O. , Murphy Brian R. , Hallerman Eric M. 
Published: November 2006

AbstractFor several fish species, increased river discharge has been linked to behavioral changes, including movement towards particular habitats. From 2000 to 2003, we used radiotelemetry to monitor habitat use by 42 muskellunge Esox masquinongy within a 17‐km reach of the New River, Virginia; to evaluate habitat selection; and to determine whether habitat use and selection were affected by discharge. Water depth, occurrence of aquatic vegetation, substrate type, and distance to riverbanks within the study reach were mapped with hydroacoustic and Global Positioning System technologies. Real‐time discharge measurements from an upstream U.S. Geological Survey stream gauge were used to classify fish locations into those made during periods of reduced (<75 m3/s) or increased (>75 m3/s) discharge. Seasonal habitat selection models for the different discharge levels were created using logistic regression. Differences in logistic regression coefficients between models were tested with multivariate chi‐square tests and Bonferroni‐corrected pairwise comparisons. Meta‐analytic averaging of Pearson's correlation coefficients was used to determine the overall effect size of discharge on habitat use by muskellunge. Overall, muskellunge exhibited a positive selection for deeper habitats; however, discharge was found to significantly affect both habitat use and selection. Habitat use was consistent with the hypothesis that fish moved to shallower habitats (both summer and winter) located closer to riverbanks (winter only) during periods of increased discharge. In terms of habitat selection, selection strengths for variables such as water depth (summer and winter) and distance to shoreline (winter only) generally weakened during periods of increased discharge, indicating that habitat use became more proportionate to availability. Increased movement as a result of increased discharge has been theorized to potentially reduce winter survival of fish because of seasonal energetic limitations. Thus, indirect effects on fish from dam operating modes (e.g., hydropeaking) may be as important as direct effects when evaluating biotic implications of water release schedules.
A Bioenergetics‐Based Approach to Explain Largemouth Bass Size in Tropical Reservoirs
Authors: Neal J. Wesley , Noble Richard L. 
Published: November 2006

AbstractIn tropical systems where largemouth bass Micropterus salmoides have been introduced, maximum age is reduced to the point where few fish live beyond 3 years and adult growth rates are very slow. Concurrently, tropical largemouth bass have an extended spawning period (up to 8 months) and individual fish spawn multiple times each year. In this study, we examined the relationship between latitude and maximum size (record angler‐caught fish) of largemouth bass from temperate to tropical environments and tested the hypothesis that the slow growth of adult largemouth bass is the result of excessive energy reallocation to reproduction. State and national record‐sized largemouth bass were plotted against latitude for the USA, Cuba, Dominican Republic, Japan, Portugal (European record), Mexico, and Puerto Rico. Largemouth bass maximum weight increased as latitude decreased from 46.8°N; peak maximum weight occurred at 27.9°N. Below 27.9°N, largemouth bass size records decreased as latitude decreased (R2 = 0.67, P < 0.0001). Bioenergetics models were used to model observed growth (in Puerto Rico) and predicted growth based on a 2% mean daily ration (MDR), and reproduction scenarios were used to explain the difference between observed and predicted growth. The predicted weight in Puerto Rico was 2.7 times higher than observed weight during a simulated 6‐month spawning season. This discrepancy could be accounted for by a range of spawning frequencies (events per season) and levels (percent body weight per spawn) for females (e.g., 10 spawns at 6% body weight per spawn). Similarly, a 15% decrease in MDR of nest‐guarding males due to reduced ability to feed accounted for the difference between predicted and observed growth.
Tag Return Estimation of Annual and Semiannual Survival Rates of Adult Female Blue Crabs
Authors: Lambert Debra M. , Hoenig John M. , Lipcius Romuald N. 
Published: November 2006

AbstractStock status of the blue crab Callinectes sapidus in Chesapeake Bay is determined by comparing current estimates of fishing mortality with biological reference points. Given the recent focus on blue crab conservation, there is a need to obtain reliable estimates of survival to compare with the biological reference points. A tagging program was initiated on the terminally molted, mature female component of the Chesapeake Bay blue crab stock to estimate annual and semiannual survival rates. Crabs were obtained from fishery‐independent research surveys throughout the bay and were measured, tagged, and released on‐site. Tagging was conducted twice per year (winter and summer) from November 2001 to March 2005. Annual survival and tag recovery rates were estimated independently for the winter and summer tagging data using Brownie models. The two independent estimates of annual survival based on winter tagging (mean ± SE = 0.081 ± 0.031) and summer tagging (0.080 ± 0.024) data were virtually identical and low. The estimated tag recovery rate was 24% based on winter tagging data and 17% based on summer tagging data. The estimated monthly survival rate during winter (mean ± SE = 0.868 ± 0.016) was higher than that during summer (0.748 ± 0.019). The low estimates of annual survival are consistent with (1) historical estimates of the percentage of age‐2 and older females in the winter dredge fishery, and (2) recent estimates of exploitation rate obtained from the ratio of catch to initial abundance. These findings indicate that survival rates of mature female blue crabs in Chesapeake Bay have remained extremely low during a period of depressed abundance, which may be preventing stock recovery. Moreover, this study represents one of the few to derive experimental Brownie model estimates of semiannual survival of an invertebrate species subject to a continuous fishery.
Marginal Decomposition of Risk Measures
Authors: Venter Gary G. , Major John A. , Kreps Rodney E. 
Published: November 2006

The marginal approach to risk and return analysis compares the marginal return from a business decision to the marginal risk imposed. Allocation distributes the total company risk to business units and compares the profit/risk ratio of the units. These approaches coincide when the allocation actually assigns the marginal risk to each business unit, i.e., when the marginal impacts add up to the total risk measure. This is possible for one class of risk measures (scalable measures) under the assumption of homogeneous growth and by a subclass (transformed probability measures) otherwise. For homogeneous growth, the allocation of scalable measures can be accomplished by the directional derivative. The first well known additive marginal allocations were the Myers-Read method from Myers and Read (2001) and co-Tail Value at Risk, discussed in Tasche (2000). Now we see that there are many others, which allows the choice of risk measure to be based on economic meaning rather than the availability of an allocation method. We prefer the term “decomposition” to “allocation” here because of the use of the method of co-measures, which quantifies the component composition of a risk measure rather than allocating it proportionally to something.Risk adjusted profitability calculations that do not rely on capital allocation still may involve decomposition of risk measures. Such a case is discussed. Calculation issues for directional derivatives are also explored.
In vivo protective performance of N95 respirator and surgical facemask
Authors: Li Y. , Wong T. , Chung J. , Guo Y.P. , Hu J.Y. , Guan Y.T. , Yao L. , Song Q.W. , Newton E. 
Published: November 2006

AbstractBackgroundThe SARS outbreak in 2003 has spawned a major controversy concerning protective performance facemasks for healthcare workers. This study reports a study on in‐vivo protective performance of surgical masks and N95 respirators.MethodsTypical surgical masks and N95 respirators used in Hong Kong hospitals were tested in comparison with those treated with nano‐functional materials (called nano‐masks) on various physical properties and in‐vivo wear filtration efficiency, as well as usability test in hospitals for surgical masks.ResultsTests on physical properties showed that N95 respirators had significantly lower air permeability and water vapor permeability than surgical masks. The in‐vivo filtration tests illustrated that N95 respirators filtered out 97% of potassium chloride (KCl) solution, while surgical masks filtered out 95% of KCl solution. Nano‐masks show stronger water repellency and antibacterial activities, but no difference in usability, comparing with normal N95 and surgical masks.ConclusionsSurgical masks can provide in‐vivo filtration protection of 95% filtration efficiency. N95 respirators provide higher in‐vivo filtration efficiency of 97% with significant reduction of air permeability and water vapor permeability. Compared to normal surgical masks/respirators, the nano‐masks can provide additional protective functions in stopping capillary diffusion and antibacterial activities. Am. J. Ind. Med. 2006. © 2006 Wiley‐Liss, Inc.
Smoking behavior in trucking industry workers
Authors: Jain Nitin B. , Hart Jaime E. , Smith Thomas J. , Garshick Eric , Laden Francine 
Published: November 2006

AbstractBackgroundIn retrospective occupational studies, the degree of confounding by smoking depends on variation in smoking among job‐related exposure groups. We assessed the relationship between job title and smoking behavior as part of a study on occupational exposures and lung cancer.MethodsA questionnaire on smoking was mailed to a sample of 11,986 trucking industry workers. Company records were used to gather other relevant information.ResultsThe response rate was 40.5%. Among white males, the age‐adjusted prevalence of ever smoking was highest among longhaul truck drivers (67%) and lowest among clerks (44%). Smoking rates among workers with other job titles were similar.ConclusionsOur results will be used to adjust for the differences in smoking among job‐related exposure groups when assessing the association between particulate matter exposure and lung cancer mortality. Our study also suggests that an assessment of methods to control for smoking should be considered in the design of retrospective occupational health studies. Am. J. Ind. Med. 2006. © 2006 Wiley‐Liss, Inc.