bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparison of Gas and Water Pycnometry of Coal Mine Wastes
Authors: Morris PH , Williams DJ 
Published: February 2009

Abstract
Coal mine washery wastes comprise two major components whose specific gravities differ markedly. Consequently, their specific gravity is much more variable than that of natural soils and is determined relatively frequently. The specific gravity of coal mine wastes is determined more rapidly and efficiently by gas pycnometry than by water pycnometry. However, the two methods give significantly different results. Results of specific gravity determinations for washery wastes from Goonyella Coal Mine in central Queensland, Australia, by gas and water pycnometry, are compared. The differences between them are shown to arise from the pore structure and particle sizes of the wastes and the interaction between the internal surface of the wastes and the pycnometric fluids.
Determination of Ionic Strength and Equilibrium Concentrations of Heavy Metals by the Electrical Conductivity Method
Authors: Kayyal MK , Mohamed AMO 
Published: February 2009

Abstract
A laboratory investigation of several types of heavy metal-soil solutions was conducted to evaluate the possibility of determining ionic strength and equilibrium concentrations of heavy metals and exchangeable cations by means of the electrical conductivity method. The characteristics of the heavy metal-soil interactions including retention of metals and release of exchangeable cations by the illitic soil were examined, and electrical conductivity and pH measurements of the heavy metal-soil solutions were performed. Test results revealed that direct determination of equilibrium concentrations of certain ionic species could be realized by means of electrical conductivity measurements of soil suspensions. This laboratory technique is based on determining the relationship between the ionic strengths of the heavy metal-soil solutions and their electrical conductivity in order to derive the necessary correlations to estimate the equilibrium concentrations. The proposed technique is expected to aid in the direct calculation of equilibrium concentrations of metal ions and heavy metals from data collected during site investigation for remedial activity via electric conductivity or soil resistivity techniques.
Determination of Shear Strength Parameters of Unsaturated Silts and Sands Based on the Water Retention Curve
Authors: Öberg AL , Sällfors G 
Published: February 2009

Abstract
Great efforts have been made to understand and determine the stress parameters of unsaturated soils. However, this requires elaborate laboratory tests, which are both difficult and time consuming to perform. A hypothesis for determination of the shear strength of unsaturated soils is suggested. The hypothesis suggests a simple way of determining the shear strength based on the water retention curve and the angle of internal friction. Values of shear strengths have been taken from the literature and compared with shear strengths calculated according to this hypothesis. The shear strengths obtained from the hypothesis are in surprisingly good agreement with those found in the literature. The suggested hypothesis is critically examined and its limitations discussed. Finally, a reasonable way of applying the hypothesis in engineering practice is proposed.
Equipment for One-Dimensional Compression and Triaxial Testing of Unsaturated Granular Soils at Low Stress Levels
Authors: Anderson WF , Goodwin AK , Pyrah IC , Salman TH 
Published: February 2009

Abstract
This paper describes the design of equipment for examining the behavior of unsaturated granular soils at low stress levels. The one-dimensional compressibility is examined in a 254-mm-diameter compression cell whose unique features include the measurement and control of low-level stresses using load cells incorporated in the loading platen and the ability to determine suctions at the base and top of the specimen. Stiffness and strength behavior is examined in a new double wall triaxial cell that allows accurate determination of the volume change of the 150-mm-diameter unsaturated specimen. Facilities are incorporated in the cell for monitoring axial and radial strains on the central portion of the specimen. A technique for preparing compacted specimens without damaging the brittle high-entry ceramics in the base plates of the cells is described. The performance of the new equipment is discussed, and results of repeatability tests are reported.
Diel Movement Patterns of Yellow Perch in a Simple and a Complex Lake Basin
Authors: Bauer William F. , Radabaugh Nicholas B. , Brown Michael L. 
Published: February 2009

Abstract
To investigate the influence habitat may have on fish movement, we tagged two length-groups of adult yellow perch Perca flavescens with ultrasonic transmitters to determine diel movement patterns in two glacial lakes with differing basin morphometries and habitat characteristics. In both lakes, movement rates increased from dawn to the diurnal period, and decreased from dusk to the nocturnal period, with lowest activity in the nocturnal period. Overall, mean period movement rates for yellow perch were higher in the simple lake than in the complex lake. Offshore movement from the nocturnal to the dawn period and onshore movement from the diurnal to the nocturnal period was evident in both length-groups in the complex lake, but not evident in the simple lake. Size segregation was apparent in the complex lake, where the small length-group was located farther from shore than the large length-group. Yellow perch in the simple lake most often used the deepest depths, whereas yellow perch in the complex lake used moderate depths. These results suggest that habitat characteristics and the complexity of a lake basin may have an influence on behavior and habitat use. With this insight into the movement patterns of yellow perch in two distinct types of lake basins, managers may consider refining sampling plans for individual lake types.
Habitat Characteristics of Black Crappie Nest Sites in an Illinois Impoundment
Authors: Phelps Quinton E. , Lohmeyer Adam M. , Wahl Nicholas C. , Zeigler John M. , Whitledge Gregory W. 
Published: February 2009

Abstract
Ten nest colonies of black crappie Pomoxis nigromaculatus were visually located and verified by angling in Campus Lake, a small urban impoundment in southern Illinois. Habitat characteristics were measured at these nest sites and compared to habitat measurements obtained from 45 unused sites. Seven habitat characteristics (substrate firmness, temperature, dissolved oxygen, distance to deep water [3.8-m depth contour], substrate type, vegetation height, and vegetation density) were significantly different between nest sites and unused sites. Although temperature and dissolved oxygen were significantly different between nest sites and unused sites, all values were within the suitable range for black crappie spawning to occur. Black crappies selected nest sites close to deep water with firm substrates and low vegetation height and density. Our results present insight on habitat characteristics of black crappie spawning locations in a small urban impoundment. Interestingly, we located several black crappie nesting colonies with more than 10 individual nests in close proximity to one another; colonial nesting by black crappies has not previously been reported in the literature. Furthermore, we suggest that degree of shoreline modification and other anthropogenic influences in and adjacent to Campus Lake did not affect black crappie nest site selection. Black crappie nest sites in Campus Lake were always located near deep water (3.8 m), in low-density, short vegetation, and on firm clay or sand substrate; because nest site selection can influence earlylife survival and recruitment of black crappie, the availability of these habitat characteristics may regulate black crappie population demographics in Campus Lake. Efforts to limit sediment inputs will be important for maintaining suitable black crappie spawning habitat in Campus Lake and other small impoundments.
Developing Model-Based Indices of Lake Whitefish Abundance Using Commercial Fishery Catch and Effort Data in Lakes Huron, Michigan, and Superior
Authors: Deroba Jonathan J. , Bence James R. 
Published: February 2009

Abstract
Fishery catch per effort (CPE) is often used to assess relative fish abundance, and in many Great Lakes and other freshwater applications the CPE index is based on either an average or the ratio of summed aggregate catch to summed aggregate effort. In particular, assessments used to estimate the abundance of lake whitefish Coregonus clupeaformis and recommend harvest quotas in 1836 Treaty-ceded waters of Lakes Huron, Michigan, and Superior assume that commercial CPE from gill-net and trap-net fisheries is proportional to abundance; however, CPE may change due to factors other than abundance, leading to violations of this assumption. To account for sources of CPE variation that are not attributable to abundance, general linear mixed models (GLMMs) were developed for each management unit and least-squares means (LSMs) for each year were used as the index of abundance. The effect of using the GLMM method for standardization was evaluated by examining the temporal trends in the proportional difference between LSMs and CPE (i.e., aggregate catch divided by aggregate effort for each year). Of the random effects included in the final GLMM for the gill-net fishery, license holder accounted for the most variation. The fixed effect of boat size category on CPE depended on lake; on average, there was little difference between boat sizes in Lake Superior, whereas large boats had a lower CPE than medium and small boats in Lakes Michigan and Huron. On average, CPE was higher from October to December than during other months. The proportional difference between LSMs and CPE trended through time in some management units, suggesting the importance of adjusting fishery CPE for effects like boat size, season, and license holder. Factors that influence lake whitefish commercial fishery CPE are similar to factors important for marine commercial fisheries.
At Loggerheads: Gear Damage in the Blue Crab Fishery Attributed to Loggerhead Sea Turtles
Authors: Avissar Naomi , Hart Kristen M. , Crowder Larry B. , Gannon Janet , Marsh Jesse C. 
Published: February 2009

Abstract
North Carolina's fishery for the blue crab Callinectes sapidus is experiencing problems with gear damage during the summer season. Individuals of a protected species, the loggerhead sea turtle Caretta caretta, are the likely culprits of crab pot damage, bait theft, and reduced crab catch, perhaps with important economic impacts. In summer 2005, we conducted a fishing study in cooperation with a pair of crabbers operating one commercial blue crab boat in Core Sound, North Carolina, to characterize location, timing, and extent of damage to crab pots. We examined spatial and temporal overlap of fishing activity with loggerhead sea turtle sightings and quantified blue crab catch. Eighty-seven percent of pots were damaged throughout the course of the study, and gear damage peaked in late June to early July. We measured a 40% reduction in blue crab catch in crab pots that were damaged. Loggerhead sea turtle sightings were consistent with areas of high gear damage. Our results should be considered by managers, who may be able to guide crabbers to concentrate fishing effort at times and areas of reduced overlap with loggerhead sea turtles so as to minimize damage.
The Physiological Response of Port Jackson Sharks and Australian Swellsharks to Sedation, Gill-Net Capture, and Repeated Sampling in Captivity
Authors: Frick Lorenz H. , Reina Richard D. , Walker Terence I. 
Published: February 2009

Abstract
Studying postrelease effects of fisheries capture on chondrichthyans in the wild poses considerable logistical challenges. We report a laboratory-based technique to (1) simulate gill-net capture of sharks, which allows monitoring the condition of animals during recovery from a controlled capture event, and (2) assess effects of sedation, serial blood sampling, and repeated exposure to experimental treatment on stress-related blood variables. Exposing Port Jackson sharks Heterodontus portusjacksoni and Australian swellsharks Cephaloscyllium laticeps to 30 min of simulated gill-net capture elicited behavioral stress (struggling and elevated ventilation rate) and minor physiological stress (elevated plasma lactate) responses but did not cause any mortality. Sedation of Australian swellsharks affected some stress-related blood variables. Repeated handling of Port Jackson sharks and Australian swellsharks at short intervals may result in elevated stress levels, but repeated exposure to simulated capture does not affect the physiological response of these two species to the treatment. Overall, the results of this study demonstrate the feasibility of simulated capture events as a technique to investigate the physiological response of sharks to capture stress.
Effects of Commercial Harvest on Shovelnose Sturgeon Populations in the Upper Mississippi River
Authors: Koch Jeff D. , Quist Michael C. , Pierce Clay L. , Hansen Kirk A. , Steuck Michael J. 
Published: February 2009

Abstract
Shovelnose sturgeon Scaphirhynchus platorynchus have become an increasingly important commercial species in the upper Mississippi River (UMR) because of the collapse of foreign sturgeon (family Acipenseridae) populations and bans on imported caviar. In response to concerns about the sustainability of the commercial shovelnose sturgeon fishery in the UMR, we undertook this study to describe the demographics of the shovelnose sturgeon population and evaluate the influence of commercial harvest on shovelnose sturgeon populations in the UMR. A total of 1,682 shovelnose sturgeon were collected from eight study pools in 2006 and 2007 (Pools 4, 7, 9, 11, 13, 14, 16, and 18). Shovelnose sturgeon from upstream pools generally had greater lengths, weights, and ages than those from downstream pools. Additionally, mortality estimates were lower in upstream pools (Pools 4, 7, 9, and 11) than in downstream pools (Pools 13, 14, 16, and 18). Linear regression suggested that the slower growth of shovelnose sturgeon is a consequence of commercial harvest in the UMR. Modeling of potential management scenarios suggested that a 685-mm minimum length limit is necessary to prevent growth and recruitment overfishing of shovelnose sturgeon in the UMR.
The national Fire and Fire Surrogate study: effects of fuel reduction methods on forest vegetation structure and fuels
Authors: Schwilk Dylan W. , Keeley Jon E. , Knapp Eric E. , McIver James , Bailey John D. , Fettig Christopher J. , Fiedler Carl E. , Harrod Richy J. , Moghaddas Jason J. , Outcalt Kenneth W. , Skinner Carl N. , Stephens Scott L. , Waldrop Thomas A. , Yaussy Daniel A. , Youngblood Andrew 
Published: February 2009

Changes in vegetation and fuels were evaluated from measurements taken before and after fuel reduction treatments (prescribed fire, mechanical treatments, and the combination of the two) at 12 Fire and Fire Surrogate (FFS) sites located in forests with a surface fire regime across the conterminous United States. To test the relative effectiveness of fuel reduction treatments and their effect on ecological parameters we used an information‐theoretic approach on a suite of 12 variables representing the overstory (basal area and live tree, sapling, and snag density), the understory (seedling density, shrub cover, and native and alien herbaceous species richness), and the most relevant fuel parameters for wildfire damage (height to live crown, total fuel bed mass, forest floor mass, and woody fuel mass).In the short term (one year after treatment), mechanical treatments were more effective at reducing overstory tree density and basal area and at increasing quadratic mean tree diameter. Prescribed fire treatments were more effective at creating snags, killing seedlings, elevating height to live crown, and reducing surface woody fuels. Overall, the response to fuel reduction treatments of the ecological variables presented in this paper was generally maximized by the combined mechanical plus burning treatment. If the management goal is to quickly produce stands with fewer and larger diameter trees, less surface fuel mass, and greater herbaceous species richness, the combined treatment gave the most desirable results. However, because mechanical plus burning treatments also favored alien species invasion at some sites, monitoring and control need to be part of the prescription when using this treatment.
Pregnancy-Induced Rise in Serum C-Peptide Concentrations in Women With Type 1 Diabetes
Authors: Nielsen Lene Ringholm , Rehfeld Jens F. , Pedersen-Bjergaard Ulrik , Damm Peter , Mathiesen Elisabeth R. 
Published: February 2009

OBJECTIVE
The purpose of this study was to investigate whether pregnancy induces increased insulin production as a marker of improved β-cell function in women with long-term type 1 diabetes.

RESEARCH DESIGN AND METHODS
This was a prospective study of 90 consecutive pregnant women with type 1 diabetes. At 8, 14, 21, 27, and 33 weeks blood samples were drawn for measurements of A1C, C-peptide, and serum glucose. C-peptide (detection limit: 6 pmol/l) was considered stimulated at a corresponding serum glucose concentration ≥5.0 mmol/l. GAD antibody concentration was determined at 8 and 33 weeks in 35 women.

RESULTS
C-peptide concentrations gradually increased throughout pregnancy regardless of serum glucose concentrations in the 90 women with a median duration of diabetes of 17 years (range 1–36 years). Among 35 women with paired recordings of stimulated C-peptide, C-peptide production was detectable in 15 (43%) at 8 weeks and in 34 (97%) at 33 weeks (P &lt; 0.0001), and median C-peptide gradually increased from 6 to 11 pmol/l (P = 0.0004) with a median change of 50% (range −50 to 3,271%) during pregnancy. GAD antibodies were present in 77% with no change from 8 to 33 weeks (P = 0.85). Multivariate regression analysis revealed a positive association between the absolute increase in C-peptide concentrations during pregnancy and decreased A1C from 8 to 33 weeks (P = 0.003).

CONCLUSIONS
A pregnancy-induced increase in C-peptide concentrations in women with long-term type 1 diabetes was demonstrated, even in women with undetectable C-peptide concentrations in early pregnancy. This increase is suggestive of improved β-cell function and was associated with improvement in glycemic control during pregnancy.
Serum Amyloid A, C-Reactive Protein, and Retinal Microvascular Changes in Hypertensive Diabetic and Nondiabetic Individuals
Authors: Stettler Christoph , Witt Nicholas , Tapp Robyn J. , Thom Simon , Allemann Sabin , Tillin Therese , Stanton Alice , O'Brien Eoin , Poulter Neil , Gallimore J. Ruth , Hughes Alun D. , Chaturvedi Nish 
Published: February 2009

OBJECTIVE
To study the association of the inflammatory markers serum amyloid A (SAA) and C-reactive protein (CRP) with retinal microvascular parameters in hypertensive individuals with and without type 2 diabetes.

RESEARCH DESIGN AND METHODS
This cross-sectional analysis was a substudy in 711 patients (159 with and 552 without diabetes) of the Anglo-Scandinavian Cardiac Outcomes Trial (ASCOT) based on digital 30-degree images of superior and inferior temporal retinal fields.

RESULTS
SAA was associated with arteriolar length-to-diameter ratio positively in nondiabetic patients (Ptrend= 0.028) but negatively in diabetic patients (Ptrend= 0.005). The difference was unlikely to be a chance finding (P = 0.007 for interaction). Similar results were found for the association of SAA with arteriolar tortuosity (P = 0.05 for interaction). Associations were less pronounced for CRP and retinal parameters.

CONCLUSIONS
Inflammatory processes are differentially involved in retinal microvascular disease in diabetic compared with nondiabetic hypertensive individuals.
Abdominal Subcutaneous Adipose Tissue: A Protective Fat Depot?
Authors: Porter Stacy A. , Massaro Joseph M. , Hoffmann Udo , Vasan Ramachandran S. , O'Donnel Christopher J. , Fox Caroline S. 
Published: February 2009

OBJECTIVE
Obesity is associated with increased metabolic and cardiovascular risk. The ectopic fat hypothesis suggests that subcutaneous fat may be protective, but this theory has yet to be fully explored.

RESEARCH DESIGN AND METHODS
Participants from the Framingham Heart Study (n = 3,001, 48.5% women) were stratified by visceral adipose tissue (VAT) into sex-specific tertiles. Within these tertiles, age-adjusted abdominal subcutaneous adipose tissue (SAT) tertiles were examined in relation to cardiometabolic risk factors.

RESULTS
In the lowest VAT tertile, risk factor prevalence was low, although systolic blood pressure in women and rates of high triglycerides, impaired fasting glucose, hypertension, and the metabolic syndrome in men increased with increasing SAT tertile (all P &lt; 0.04). In contrast, in the top VAT tertile, lower triglycerides were observed in men with increasing SAT (64.4% high triglycerides in SAT tertile 1 vs. 52.7% in SAT tertile 3, P = 0.03). Similar observations were made for women, although results were not statistically significant (50.6% high triglycerides in SAT tertile 1 vs. 41.0% in tertile 3, P = 0.10). Results in the highest VAT tertile were notable for a lack of increase in the prevalence of low HDL in men and women and in rates of impaired fasting glucose in men with increasing subcutaneous fat, despite sizable differences in BMI across SAT tertiles (27.1 to 36.3 kg/m2[women]; 28.1 to 35.7 kg/m2[men]).

CONCLUSIONS
Although adiposity increases the absolute risk of metabolic and cardiovascular disease, abdominal subcutaneous fat is not associated with a linear increase in the prevalence of all risk factors among the obese, most notably, high triglycerides.
Brief communication: Plio‐Pleistocene eagle predation on fossil cercopithecids from the Humpata Plateau, southern Angola
Authors: Gilbert Christopher C. , McGraw W. Scott , Delson Eric 
Published: February 2009

AbstractRecent studies suggest a large raptor such as the crowned eagle (Stephanaoetus coronatus) was responsible for collecting at least a portion of the primate fauna from the South African fossil site of Taung, including its lone hominin specimen. This taphonomic signature at Taung is currently regarded as a unique and, most likely, isolated case in primate and human evolution. However, the activities of large, carnivorous birds should also be detectable at other primate fossil localities in Africa if raptors have been a strong selective force throughout primate evolution. Over the last 60 years, a collection of extinct cercopithecids has been assembled from several cave breccias on the Humpata Plateau in southern Angola. The material, dated near the Plio‐Pleistocene boundary, includes an assortment of craniodental and postcranial remains variably assigned to Papio (Dinopithecus) cf. quadratirostris, Parapapio, Cercopithecoides, and Theropithecus. We compare the Angolan and Taung material to remains of extant primates killed by crowned eagles in the Ivory Coast's Tai National Park. Our analysis indicates that the size distribution and composition of fauna from the localities is quite similar and that there are striking consistencies in damage to the crania from each site. The absence of large bodied (>20 kg) primates and other mammalian taxa at the Taung hominin locality and Tai, and their rarity in Angola, combined with the strong likelihood that raptor nests were positioned near fissure openings at both fossil localities, provides additional support for eagle involvement. On the basis of this evidence, we conclude that at least some of the Angolan cercopithecids were most likely raptor prey and hypothesize that raptor predation has been a strong and perhaps underappreciated selective force during the course of primate evolution. Am J Phys Anthropol 2009. © 2009 Wiley‐Liss, Inc.