Infiltration Through Reconstructed Surface Mined Spoils and Soils

An extensive series of tests involving reconstructed profiles of spoil and topsoil material from a Western Kentucky surface mine site was conducted with a laboratory infiltrometer system. Infiltration through the reconstructed spoil profiles was very slow despite the coarse nature of the material. Low infiltration rates could be attributed to the material having a well-graded texture and to the high densities of the profiles. Infiltration through topsoil horizons was controlled, for the most part, by conditions at the surface. Following wetting, infiltration rates were primarily controlled by the hydraulic characteristics of the less permeable sub horizon of the spoil material. Except in very early stages, rainfall rate had little effect upon infiltration rate (or volume) through the spoil and topsoil profiles. Infiltration was, however, significantly influenced by initial moisture content and density

Predicting Infiltration and Surface Runoff from Reconstructed Spoils and Soils

A laboratory system was fabricated to measure infiltration and runoff from spoil and soil profiles constructed in rectangular bins. Construction, calibration and operation of a rainfall simulator is discussed and instrumentation used to measure transient infiltration and transmittance of water through experimental profiles is described. Spoil and soil materials from surface mines in Eastern and Western Kentucky were transported to the laboratory and used in constructing experimental profiles in rectangular bins (0.91 x 1.83 x 1.07 m). An extensive series of infiltration experiments were conducted utilizing a rainfall simulator and soil moisture monitoring instrumentation. A dual probe gamma density gauge was used to measure moisture content and tensiometers were used to measure soil matric suction. Initial moisture content, bulk density and rainfall rate were varied and respective responses of infiltration characteristics determined. Extremely low infiltration rates in Western Kentucky spoil material was attributed to relatively high bulk densities and well-graded particle constituency. Conversely, extremely high infiltration rates were observed for Eastern Kentucky shale material even at very high bulk densities. The sandstone material, however, exhibited infiltration rates of the same order of magnitude as that of Western Kentucky spoil material. Soil water characteristic curves were developed using the Brooks-Corey and Gardner procedures, based upon desortpion tensiometer data. Unsaturated hydraulic conductivity values were determined using the plane of zero flux procedure and compared with predictions resulting from models described by Campbell, Burdine and Mualem for situations involving reconstructed soil and spoil materials. There was generally good agreement between the models and plane of zero flux results, and excellent agreement with Campbell\u27s predictions. The infiltration process was modeled with the SCS curve number method, a modified form of Holtan\u27s equation, the Green-Ampt model and Richard\u27s equation. SCS curve numbers were determined by fitting the method to the observed results. Richards\u27 equation gave very good estimates of the infiltration process through the spoil profiles, but was only slightly better than the Green-Ampt model. None .of the models worked well for the profiles where macropore flow occurred through a two layer topsoil over spoil system

Comparison of Four Infiltration Models in Characterizing Infiltration Through Surface Mine Profiles

A laboratory infiltrometer system was used to evaluate the infiltration process through reconstructed surface mine profiles. Six different profiles were subjected to constant simulated rainfall intensities for selected test conditions. Surface runoff rates were monitored and transient soil moisture contents in the profiles were measured with a gamma density gauge. Unsaturated hydraulic conductivity relationships were determined using Campbelfs method and the zero-flux procedure. The infiltration process was modeled by the SCS curve number method, a form of Holtan\u27s equation, the Green-Ampt model and Richards\u27 equation. SCS curve numbers were determined by fitting the method to the observed results. Richards\u27 equation gave very good estimates of the infiltration process through the spoil profiles, but was only slightly better than the Green-Ampt model. None of the models worked well for the profiles where macropore flow occurred through a two layer, topsoil-over-spoil system

Use of high resolution bathymetry and backscatter for mapping depositional environments on the New Hampshire continental shelf

The New Hampshire continental shelf is extremely heterogeneous and includes extensive bedrock outcrops, sand and gravel deposits and muddy basins. Many of the depositional features are glacial in origin and have been significantly modified by marine processes as sea level fluctuated since the end of the last major glaciation. Recent high resolution multibeam echosounder (MBES) bathymetric and backscatter surveys by the National Ocean Survey and University of New Hampshire Center for Coastal and Ocean Mapping/Joint Hydrographic Center has revealed features of the seafloor in exceptional detail that had not been previously described. Synthesis of the MBES bathymetry and backscatter, coupled with an extensive archived database consisting of subbottom seismics, bottom sediment grain size data and vibracores, is being used to develop new surficial geology maps and significantly improve our knowledge of the character and origin of the major depositional features of the New Hampshire shelf and vicinity (with support from the Bureau of Ocean Energy Management). Included are a number of large glacial features (e.g., drumlins) covering the bedrock that have been modified by marine processes (waves and currents). Some of the larger features were previously mapped (Birch, F.S. 1984. A geophysical survey of sedimentary deposits on the inner continental shelf of New Hampshire. Northeastern Geology 6:207-221), but the lack of high resolution bathymetry limited their characterization and interpretation. The new high resolution bathymetry and backscatter has resolved this limitation. Some of these deposits may represent significant sand and gravel deposits on the New Hampshire continental shelf that have the potential for future use for beach nourishment and other efforts to build coastal resiliency

Measuring Self-assessment: Current State of the Art

The competent physician pursues lifelong learning through the recognition of deficiencies and the formulation of appropriate learning goals. Despite the accepted theoretical value of self-assessment, studies have consistently shown that the accuracy of self-assessment is poor. This paper examines the methodological issues that plague the measurement of self-assessment ability and presents several strategies that address these methodological problems within the current paradigm. In addition, the article proposes an alternative conceptualization of self-assessment and describes its associated methods. The conclusions of prior research in this domain must be re-examined in light of the common pitfalls encountered in the design of the studies and the analyses of the data. Future efforts to elucidate self-assessment phenomena need to consider the implications of this review.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/41768/1/10459_2004_Article_397832.pd

Regulatory effects of interleukin‐11 during acute lung inflammatory injury

The role of interleukin‐11 (IL‐11) was evaluated in the IgG immune complex model of acute lung injury in rats. IL‐11 mRNA and protein were both up‐regulated during the course of this inflammatory response. Exogenously administered IL‐11 substantially reduced, in a dose‐dependent manner, the intrapulmonary accumulation of neutrophils and the lung vascular leak of albumin. These in vivo anti‐inflammatory effects of IL‐11 were associated with reduced NF‐κB activation in lung, reduced levels of tumor necrosis factor α (TNF‐α) in bronchoalveolar lavage (BAL) fluids, and diminished up‐regulation of lung vascular ICAM‐1. It is interesting that IL‐11 did not affect BAL fluid content of the CXC chemokines, macrophage inflammatory protein‐2 (MIP‐2) and cytokine‐inducible neutrophil chemoattractant (CINC); the presence of IL‐11 did not affect these chemokines. However, BAL content of C5a was reduced by IL‐11. These data indicate that IL‐11 is a regulatory cytokine in the lung and that, like other members of this family, its anti‐inflammatory properties appear to be linked to its suppression of NF‐κB activation, diminished production of TNF‐α, and reduced up‐regulation of lung vascular ICAM‐1. J. Leukoc. Biol. 66: 151–157; 1999.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141937/1/jlb0151.pd

The Elusive Baseline of Marine Disease: Are Diseases in Ocean Ecosystems Increasing?

Disease outbreaks alter the structure and function of marine ecosystems, directly affecting vertebrates (mammals, turtles, fish), invertebrates (corals, crustaceans, echinoderms), and plants (seagrasses). Previous studies suggest a recent increase in marine disease. However, lack of baseline data in most communities prevents a direct test of this hypothesis. We developed a proxy to evaluate a prediction of the increasing disease hypothesis: the proportion of scientific publications reporting disease increased in recent decades. This represents, to our knowledge, the first quantitative use of normalized trends in the literature to investigate an ecological hypothesis. We searched a literature database for reports of parasites and disease (hereafter “disease”) in nine marine taxonomic groups from 1970 to 2001. Reports, normalized for research effort, increased in turtles, corals, mammals, urchins, and molluscs. No significant trends were detected for seagrasses, decapods, or sharks/rays (though disease occurred in these groups). Counter to the prediction, disease reports decreased in fishes. Formulating effective resource management policy requires understanding the basis and timing of marine disease events. Why disease outbreaks increased in some groups but not in others should be a priority for future investigation. The increase in several groups lends urgency to understanding disease dynamics, particularly since few viable options currently exist to mitigate disease in the oceans

Neutrophil Chemotactic Activity and C5a Following Systemic Activation of Complement in Rats

Using ELISA analysis, rat C5a was stimulated in serum from rats undergoing systemic activation of complement after intravenous infusion of purified cobra venom factor (CVF). Biological (neutrophil chemotactic) activity was also assessed. Serum levels of C5a were directly proportional to the amount of CVF infused. C5a and neutrophil chemotactic activity, peaked by 5 min, then plateaued. In vitro addition of anti-C5a to serum samples of CVF-infused rats totally abolished chemotactic activity, indicating that all biological activity could be ascribed to C5a. Blood neutrophils obtained from CVF-infused animals showed a significant upregulation of CD11b, the increase being reduced (38%) in animals pretreated with anti-C5a. These findings indicate that infusion of CVF into rats produces generation of C5a, all chemotactic activity in serum being related to C5a. The in vivo generation of C5a is, at least inpart, responsible for upregulation of CD11b on blood neutrophils.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44517/1/10753_2004_Article_426059.pd