bluuebunny/crossref_metadata_2025_split huggingface dataset:
New Chemical Antistripping Additives for Bituminous Mixtures
Authors: Abo-Qudais S , Walid Mulqi M 
Published: August 2005

Abstract
The main objective of this study was to develop new, low cost, chemical antistripping additives that have low negative effects on Hot-Mix Asphalt (HMA) properties such as stability and low temperature cracking potential. To achieve this objective, HMA specimens were prepared using limestone aggregate, asphalt with 80/100 penetration, and different types of chemical antistripping compounds. Eighteen different low cost chemical compounds were prepared and added to the HMA at different percentages. The effect of 28 different combinations of additive types and amounts on the HMA stripping was evaluated using the modified Texas Boiling Test. The results indicated that out of the 28 evaluated combinations of additive type and amount, five combinations caused a negative or no impact on stripping resistance. On the other hand, twelve additive combinations show relatively small improvements in stripping resistance. Another 11 additive combinations showed a positive effect on stripping resistance. Five of these 11 additives showed a high positive improvement in the stripping resistance (increase in coating areas was greater than 20%). However, of these five additives, four caused a high reduction in the asphalt ductility and penetration, while the fifth one (Aluminum mono-stearate) caused a small reduction in ductility and an insignificant change in penetration. This suggests that this additive is suitable for use as an antistripping agent.
The effects of antistripping additives in improving stripping resistance may be explained by the formation of strong links between the metal surfactant and with both the aggregate and asphalt. The stripping resistance of metal surfactants derived from the saponification reaction between the metal hydroxide [Ca(OH)2 and Al(OH)3] and the triglyceride of stearic acid was less than those derived from pure stearic acid (by neutralizing the stearic acid with the metal hydroxides). This may be explained by the presence of glycerol in the metal surfactants derived from the saponification reaction. Since glycerol contains three hydroxyl groups, it makes strong hydrogen bonding with water and appreciable interaction with the metal surfactant due to the presence of dipole-dipole forces. Accordingly, some of the metal surfactant and its attached asphalt are leached out during the boiling test producing a lower anti stripping effect.
Brown Bullhead as an Indicator Species: Seasonal Movement Patterns and Home Ranges within the Anacostia River, Washington, D.C.
Authors: Sakaris Peter C. , Jesien Roman V. , Pinkney Alfred E. 
Published: August 2005

AbstractElevated liver and skin tumor prevalence has been reported in brown bullhead Ameiurus nebulosus from the tidal Anacostia River, Washington, D.C. Movement data are needed to effectively use tumor prevalence as an indicator of habitat quality. We used ultrasonic telemetry to verify the residency of 40 adult brown bullheads (250–310 mm total length) in the Anacostia River during summer 2000, spring 2001, and fall–winter 2001–2002. During summer (10 fish tagged), fish remained within 500 m of their capture–release location, and their mean 95% minimum area polygon (MAP) and linear home ranges were 4.5 ha and 0.50 km. During spring (12 fish tagged), most fish traveled upstream of the capture–release location as water temperatures increased; they were approximately 1 km upriver by the end of the season. Mean 95% MAP and linear home ranges in spring were 19.7 ha and 2.1 km. During fall–winter (18 fish tagged), fish released in the river remained within 4.2 km upstream and 3.1 km downstream of their capture– release location, and their mean 95% MAP and linear home ranges were 15.9 ha and 2.1 km. In comparison, the 95% MAP and linear home ranges of fish released in Lake Kingman (a tidal freshwater impoundment of the Anacostia) were 5.8 ha and 0.58 km. No fish were located outside of the Anacostia River. We conclude that adult brown bullheads were resident in the system throughout the year.
Recolonization by Warmwater Fishes and Crayfishes after Severe Drought in Upper Coastal Plain Hill Streams
Authors: Adams Susan B. , Warren Melvin L. 
Published: August 2005

AbstractExtreme hydrologic disturbance, such as a supraseasonal drought, can dramatically influence aquatic communities. Documentation of the responses of aquatic communities after such disturbances provides insight into the timing, order, and mechanisms of recolonization. Postdisturbance recolonization of streams depends on many factors, including the region and characteristics of the disturbance relative to the disturbance regime. A supraseasonal drought that ended in the fall of 2000 resulted in the desiccation of numerous small streams or stream segments in northern Mississippi that were normally perennial. We repeatedly sampled fish and crayfish during predrought and postdrought periods in seven stream reaches that dried and five that remained flowing during the drought. From immediately after the drought until early summer of 2001, postdrought fish and crayfish assemblages differed from predrought assemblages in dry sites but not in flowing sites. The initially slow recolonization rates increased considerably during early spring 2001 so that by June 2001 fish catch per unit effort, species composition, and species richness in dry sites no longer differed significantly from predrought values. The fish recolonization process was highly ordered, as indicated by significant patterns of species nestedness over time in dry sites. Crayfish numerical recovery followed a pattern similar to that for fish, and we captured more crayfish in June 2001 than in the predrought period. Patterns in fish and crayfish population size structures over time indicated that repopulation was due to both immigration and reproduction. Recolonization was indicative of high mobility, particularly during spring and early summer. Although the fauna was quite resilient to stream desiccation, the effects on fish species composition and fish and crayfish size structure persisted 1 year after the drought.
Close Encounters with a Fish Screen: Integrating Physiological and Behavioral Results to Protect Endangered Species in Exploited Ecosystems
Authors: Swanson Christina , Young Paciencia S. , Cech Joseph J. 
Published: August 2005

AbstractProtection of endangered species that are restricted to highly modified ecosystems and threatened by anthropogenic activities often includes regulatory design and operational criteria for structures and facilities located within the species' critical habitat. In many freshwater systems, loss of fishes at water diversions has contributed to population declines of multiple species. Fish screens prevent removal of fish from the habitat; however, under current design criteria, the degree of protection provided by screens is unknown for most affected species. We used a large laboratory‐based flume to observe and quantify the responses of delta smelt Hypomesus transpacificus, an endangered osmerid threatened by water diversions in California's Sacramento–San Joaquin Estuary, to a simulated fish screen. For a range of flow and environmental conditions, we measured screen contact frequency, swimming behavior, injuries, and survival. Delta smelt experienced frequent temporary contact with the screen, and contact rates were influenced by flow and time of day–light level. Contact was injurious, and postexperiment mortality rates were directly related to both contact frequency and severity as well as temperature. Quantitative models showed that, for this species, both behavioral responses such as swimming velocity and physiological responses to fish screen contact, as modified by environmental conditions, controlled the species' performance and its risk from the diversion and the screen. The results illustrate that ecologically effective protection strategies and regulatory criteria developed on the basis of multiple integrated responses of the organism to the stressor offer greater benefits and certainty to both the organism and the regulated activities.
Simple and Efficient Isolation of Hematopoietic Stem Cells from H2K-zFP Transgenic Mice
Authors: Surdez Didier , Kunz Beatrice , Wagers Amy J. , Weissman Irving L. , Terskikh Alexey V. 
Published: August 2005

Abstract
We have generated a transgenic mouse line that allows for simple and highly efficient enrichment for mouse hematopoietic stem cells (HSCs). The transgene expresses a green fluorescent protein variant (zFP) under the control of H2Kb promoter/enhancer element. Despite the broad zFP expression, transgenic HSCs express exceptionally high levels of zFP, allowing prospective isolation of a population highly enriched in HSCs by sorting the 0.2% of the brightest green cells from the enriched bone marrow of H2K-zFP mice. Up to 90% of zFPbright cells are also c-kithigh, Sca-1high, Linneg, Flk-2neg, which is a bona fide phenotype for long-term HSCs. Double-sorted zFPbright HSCs were capable of long-term multilineage reconstitution at a limiting dilution dose of approximately 12 cells, which is comparable to that of highly purified HSCs obtained by conventional multicolor flow cytometry. Thus, the H2K-zFP transgenic mice provide a straightforward and easy setup for the simple and highly efficient enrichment for genetically labeled HSCs without using fluorescence-conjugated monoclonal antibodies. This approach will greatly facilitate gene transfer, including short interfering RNA for gene knockdown, into HSCs and, consequently, into all other hematopoietic lineages.
Metals Distribution and Interactions in Tissues of Shrews (Sorexspp.) from Copper‐ and Zinc‐Contaminated Areas in Poland
Authors: Świergosz‐Kowalewska R. , Gramatyka M. , Reczyński W. 
Published: August 2005

ABSTRACTTo assess the risk from heavy metal accumulation to insectivorous species exposed to different pollutants, shrews [Sorex araneus(Linnaeus 1758) andSorex minutus(Linnaeus 1766)] were collected in the Olkuski Ore Region (OOR; a Zn and Cd smelter area), Legnicko–Głogowski Copper Mine Region (LGCR; a copper ore‐mining area), and Białowieża Forest (BF; a control area). A few sites were chosen in each region and a total of 57 animals were collected from them. The liver and kidneys were dissected from the animals, dried, and digested in a 4:1 mixture of HNO3(nitric acid) and HClO4(perchloric acid). Cadmium, lead, zinc, copper, and iron were determined in the samples by flame or flameless atomic absorption spectrometry. The interactions between toxic and essential metals were calculated for each tissue. The data showed that accumulation of metals by insectivores is high; shrews accumulated much higher amounts of cadmium and lead than bank voles, studied by other researchers, from the same areas. The expected high tissue accumulation of copper at LGCR and zinc at OOR was not seen, but the levels of both elements were higher in the tissues of shrews from OOR than from LGCR. The lowest copper concentrations were in the tissues of shrews from BF. The highest cadmium and lead concentrations were found in the tissues of shrews from OOR. Some significant correlations were found between the tissue concentrations of xenobiotic and essential metals (e.g., between cadmium and zinc and between lead and iron).
The Effect of Flow Path and Mixing Layer on Phosphorus Release
Authors: Sánchez M. , Boll J. 
Published: August 2005

ABSTRACTSoil phosphorus (P) concentrations typically are greater in surface soils compared with subsurface soils. Surface soils have a greater chance to interact with runoff leading to P transport to streams. The thin surface layer where P concentrates is referred to as the mixing layer denoting where water and chemicals mix during transport. The objective of this study was to evaluate the effect of hydrologic flow paths on soluble reactive phosphorus (SRP) loss at two temperatures. Laboratory flumes were built to simulate infiltration, return flow, saturation excess, and interflow, and subsequent interaction with the mixing layer. The sandy loam soil in the flumes was kept at saturation throughout all experiments, so that biochemical effects were normalized. Flow through the flumes was maintained at 3.6 mm/h for 24 to 99 h (at 6 and 25°C) with water entering and exiting the flumes at different ports (to simulate different flow paths) or as low intensity rainfall. Experiments were performed with and without an artificially created P‐enriched surface layer (5 mm thick, total P increased from 1010 mg/kg in the original soil to 2310 mg/kg by addition of dissolved phosphate). Results indicated that (i) SRP release was greater in soil with a mixing layer than in soil without a mixing layer; (ii) SRP release was greater during experiments at 25°C than at 6°C; (iii) at 25°C, SRP release was greatest when water traversed the mixing layer in the upward direction (i.e., in return flow), and by flow parallel to the mixing layer (i.e., surface runoff); and (iv) at 6°C, SRP release in subsurface flow following rainfall was slightly greater than in return flow and infiltration. Our results confirmed the presence of a variable, temperature‐dependent desorption process when runoff water interacted with the mixing layer. Our findings have important implications for how different water flow paths in and over the soil interact with P in the soil, and what the ultimate concentration will be in runoff and interflow.
Degradation of Potassium Formate in the Unsaturated Zone of a Sandy Aquifer
Authors: Hellstén Pasi P. , Kivimäki Anna‐Liisa , Miettinen Ilkka T. , Mäkinen Risto P. , Salminen Jani M. , Nystén Taina H. 
Published: August 2005

ABSTRACTThis paper presents results from a lysimeter experiment on the fate of potassium formate, an alternative deicing agent. The experiment was performed through the winter and spring to identify any thermal sensitivity in the transport and biodegradation of formate in the lysimeter. Ninety‐eight percent of the total quantity of formate applied was degraded while percolating through the 1.7‐m‐thick unsaturated sand layer within the lysimeter. Concomitantly, the bicarbonate concentration of the percolating water increased. The low concentrations of nitrogen (0.02 mg L−1) and phosphorous (<0.002 mg L−1) in the percolated water, however, potentially limited microbial activity. During the study period, 99% of the applied potassium was retained in the lysimeter, and the ion exchange between the potassium and a variety of monovalent and divalent ions was assumed to be responsible for the leaching of barium, calcium, magnesium, and sodium from the soil material. Except for manganese, the concentrations of the studied metals in the percolated water did not exceed the threshold values set for drinking water by the Council of the European Union. By contrast, the application of potassium formate had a detrimental effect on the vegetation on the lysimeter. To conclude, formate was effectively degraded in the sandy lysimeter and its application did not cause major undesirable changes in the quality of the percolating water. Further research at field scale is, however, needed for instance on the biodegradation of potassium formate and on its impacts on roadside vegetation.
Environmental Implications of Adopting a Dominant Factor Approach to Salinity Management
Authors: Shani Uri , Ben‐Gal Alon , Dudley Lynn M. 
Published: August 2005

ABSTRACTAdditive or multiplicative models of crop response on which salinity management theory have been developed may lead to an erroneous perception regarding compensative interaction among salinity and other growth factors. We present results from studies of biomass production and transpiration of corn (Zea mays L. cv. Jubilee), melon (Cucumis melo L. subsp. melo cv. Galia), tomato (Lycopersicon esculentum Mill. cv. 5656), onion (Allium cepa L. cv. HA 944), and date palms (Phoenix dactylifera L. cv. Medjool) under salinity combined with water or nitrate (growth promoters) or with boron (growth inhibitor). The measured crop responses were to the more severe stress rather than to combinations of the individual effects of the various stresses. Consequences of shifting management of saline water to a dominant factor approach include reduction of environmental contamination and conservation of water resources.
Degradation of Methyl Isothiocyanate and Chloropicrin in Forest Nursery Soils
Authors: Zhang Y. , Spokas K. , Wang D. 
Published: August 2005

ABSTRACTRecent studies have observed enhanced degradation of methyl isothiocyanate (MITC) from repeated fumigation in agricultural soils. Little is known about fumigant degradation in forest and nursery soils. This study was conducted to determine degradation rates of MITC and chloropicrin (CP) in two forest soils and the impacts of nursery management on degradation of MITC and CP. The half‐life values of MITC and CP were evaluated in the laboratory under isothermal conditions (22 ± 2°C). Three rates representing 0.5×, 1×, and 2× field application rates for each fumigant were used in laboratory incubations. Effect of microbial degradation was determined by conducting incubations with both fresh and sterilized soils. Soil moisture effects were also studied. There was no difference in MITC or CP degradation between fumigated and nonfumigated forest nursery soils. Soil sterilization and high soil moisture content (15% by wt.) reduced MITC and CP degradation. The degradation rates of MITC and CP varied with factors such as nursery history, fumigant application rates, and freshness of tested soils.
Cadmium Solubility and Sorption in a Long‐Term Sludge‐Amended Arable Soil
Authors: Bergkvist Petra , Berggren Dan , Jarvis Nicholas 
Published: August 2005

ABSTRACTCadmium solubility and sorption in an arable clay loam soil that had received sewage sludge for 41 years were compared to an unsludged control in batch studies. Soil pH dominated Cd sorption, explaining >92% of the variation in Kd values in both treatments. At any pH, Cd sorption was apparently slightly but significantly (p < 0.05) smaller in the sludge‐amended soil compared to the control, even though the organic carbon content was 70% larger and the ammonium oxalate–extractable iron content was roughly doubled. Correction for dissolved organic carbon (DOC) complexation with the speciation model WHAM reduced the difference in sorption between treatments, but the sludged soil still had significantly smaller Kd values (p < 0.01). Batch equilibrations without addition of Cd showed that there was no significant difference in the solubility of “native” cadmium (defined as EDTA‐extractable Cd) in sludged and control soils. The reason for the lack of increase in Cd sorption in the sludge‐amended soil has not been established, but it may be due to competition for sorption sites on humic compounds with sludge‐derived Fe and trace metals such as zinc. The fact that the pyrophosphate‐extractable (i.e., organically associated) iron content was seven times larger in the sludged soil provides some supporting evidence for this hypothesis.
Corn Residue Level and Manure Application Timing Effects on Phosphorus Losses in Runoff
Authors: Grande Joseph D. , Karthikeyan K. G. , Miller Paul S. , Powell J. Mark 
Published: August 2005

ABSTRACTGrowing interest in corn (Zea mays L.) silage utilization on Wisconsin dairy farms may have implications for nutrient losses from agricultural lands. Increasing the silage cutting height will increase residue cover and could reduce off‐site migration of sediments and associated constituents compared with conventional silage harvesting. We examined the effects of residue level and manure application timing on phosphorus (P) losses in runoff from no‐till corn. Treatments included conventional corn grain (G) and silage (SL; 10‐ to 15‐cm cutting height) and nonconventional, high‐cut (60–65 cm) silage (SH) subjected to different manure application regimes: no manure (N) or surface application in fall (F) or spring (S). Simulated rainfall (76 mm h−1; 1 h) was applied in spring and fall for two years (2002–2003), runoff from 2.0‐ × 1.5‐m plots was collected, and subsamples were analyzed for dissolved reactive phosphorus (DRP), total phosphorus (TP), and P mass distribution in four particle size classes. Total P and DRP loads were inversely related to percent residue cover, but both TP and DRP concentrations were unaffected by residue level. Manure application increased DRP concentrations in spring runoff by two to five times but did not significantly affect DRP loads, since higher concentrations were offset by lower runoff volumes. Spring manure application reduced TP loads in spring runoff by 77 to 90% compared with plots receiving no manure, with the extent of reductions being greatest at the lower residue levels (<24%). The TP concentration in sediments increased as particle size decreased. Manure application increased the TP concentration of the 0‐ to 2‐μm fraction by 79 to 125%, but elevated the 2‐ to 10‐ and 10‐ to 50‐μm fractions to a lesser extent. Recent manure additions were most influential in enriching transported sediments with P. By itself, higher residue cover achieved by high‐cutting silage was often insufficient to lower P losses; however, the combination of manure application and higher residue levels significantly reduced P losses from corn fields harvested for silage.
Fire and Grazing Effects on Wind Erosion, Soil Water Content, and Soil Temperature
Authors: Vermeire Lance T. , Wester David B. , Mitchell Robert B. , Fuhlendorf Samuel D. 
Published: August 2005

ABSTRACTSelective grazing of burned patches can be intense if animal distribution is not controlled and may compound the independent effects of fire and grazing on soil characteristics. Our objectives were to quantify the effects of patch burning and grazing on wind erosion, soil water content, and soil temperature in sand sagebrush (Artemisia filifolia Torr.) mixed prairie. We selected 24, 4‐ha plots near Woodward, OK. Four plots were burned during autumn (mid‐November) and four during spring (mid‐April), and four served as nonburned controls for each of two years. Cattle were given unrestricted access (April–September) to burned patches (<2% of pastures) and utilization was about 78%. Wind erosion, soil water content, and soil temperature were measured monthly. Wind erosion varied by burn, year, and sampling height. Wind erosion was about 2 to 48 times greater on autumn‐burned plots than nonburned plots during the dormant period (December–April). Growing‐season (April–August) erosion was greatest during spring. Erosion of spring‐burned sites was double that of nonburned sites both years. Growing‐season erosion from autumn‐burned sites was similar to nonburned sites except for one year with a dry April–May. Soil water content was unaffected by patch burn treatments. Soils of burned plots were 1 to 3°C warmer than those of nonburned plots, based on mid‐day measurements. Lower water holding and deep percolation capacity of sandy soils probably moderated effects on soil water content and soil temperature. Despite poor growing conditions following fire and heavy selective grazing of burned patches, no blowouts or drifts were observed.