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Articles 69841 - 69870 of 78967
Full-Text Articles in Entire DC Network
Long-Term Prairie Falcon Population Changes In Relation To Prey Abundance, Weather, Land Uses, And Habitat Conditions, Karen Steenhof, Michael Kochert, Leslie B. Carpenter, Robert N. Lehman
Long-Term Prairie Falcon Population Changes In Relation To Prey Abundance, Weather, Land Uses, And Habitat Conditions, Karen Steenhof, Michael Kochert, Leslie B. Carpenter, Robert N. Lehman
United States Geological Survey: Staff Publications
We studied a nesting population of Prairie Falcons (Falco mexicanus) in the Snake River Birds of Prey National Conservation Area (NCA) from 1974-1997 to identify factors that influence abundance and reproduction. Our sampling period included two major droughts and associated crashes in Townsend's ground squirrel (Spermophilus townsendii) populations. The number of Prairie Falcon pairs found on long-term survey segments declined significantly from 1976-1997. Early declines were most severe at the eastern end of the NCA, where fires and agriculture have changed native shrubsteppe habitat. More recent declines occurred in the portion of canyon near the Orchard …
Source Water Assessment Plan, Water Quality Division
Source Water Assessment Plan, Water Quality Division
Publications (WR)
The safe drinking water amendments of 1996 placed a strong emphasis on the goal to establish a nationwide effort to protect drinking water sources. As part of that goal, the legislation provided for a preliminary assessment of drinking water sources and an inventory of surrounding adjacent land use (ALUs). This nationwide effort will result in the first comprehensive look at the nation's drinking water sources from an assessment perspective. One of the outcomes of this nationwide assessment will be information that public water systems (PWSs) can use to help determine appropriate monitoring frequencies and to protect their sources of drinking …
Arizona Source Water Assessment Plan Final Draft, Arizona Department Of Environmental Quality
Arizona Source Water Assessment Plan Final Draft, Arizona Department Of Environmental Quality
Publications (WR)
The safe drinking water amendments of 1996 placed a strong emphasis on the goal to establish a nationwide effort to protect drinking water sources. As part of that goal, the legislation provided for a preliminary assessment of drinking water sources and an inventory of surrounding adjacent land use (ALUs). This nationwide effort will result in the first comprehensive look at the nation's drinking water sources from an assessment perspective. One of the outcomes of this nationwide assessment will be information that public water systems (PWSs) can use to help determine appropriate monitoring frequencies and to protect their sources of drinking …
Internal Temperature Of Douglas-Fir Buds Is Altered At Elevated Temperature, Martha E. Apple, Melissa S. Lucash, David M. Olszyk, David T. Tingey, Donald L. Phillips
Internal Temperature Of Douglas-Fir Buds Is Altered At Elevated Temperature, Martha E. Apple, Melissa S. Lucash, David M. Olszyk, David T. Tingey, Donald L. Phillips
Environmental Science and Management Faculty Publications and Presentations
Pseudotsuga menziesii (Douglas-fir) saplings were grown in sun-lit controlled environment chambers at ambient or elevated (4°C above ambient) temperature. We measured internal temperatures of vegetative buds with thermocouple probes and compared temperatures of normal buds and abnormal buds with loosened, rosetted outer scales in elevated temperature chambers. The abnormal buds had higher and earlier peak daily temperatures than normal buds. Elevated temperature may influence the internal temperature of buds and contribute to the development of abnormal, rosetted buds with loosened outer scales. Abnormal bud development may alter branching patterns and allometry of Douglas-fir trees subjected to climatic change.
Preliminary Ecological Risk Assessment To Assess The Implications Of Replacing Chromium Plating With Tantalum Coating, Erik Jonathan Weiss
Preliminary Ecological Risk Assessment To Assess The Implications Of Replacing Chromium Plating With Tantalum Coating, Erik Jonathan Weiss
Theses
An ecological risk assessment process requires a modeling tool that can adapt to changing environmental conditions. Computer simulation tools are a useful means to develop an ecological risk assessment, because if properly used they can provide an organized framework to evaluate multiple data sources, complex problems and hypotheses. An evaluation was completed of the University of Tennessee CHEMS-1 model that ranks and scores contaminant toxicity and exposure potential. Tantalum posed less of a hazard than hexavalent chromium to the terrestrial and aquatic animals. Although, results indicated that the vanadium compounds, in particular vanadium pentoxide, presented the greatest hazard, with hexavalent …
A Comparative Study Of Sequence Analysis Tools In Computational Biology, Wei-Jen Chuang
A Comparative Study Of Sequence Analysis Tools In Computational Biology, Wei-Jen Chuang
Theses
A biomolecular object, such as a deoxyribonucleic acid (DNA), a ribonucleic acid (RNA) or a protein molecule, is made up of a long chain of subunits. A protein is represented as a sequence made from 20 different amino acids, each represented as a letter. There are a vast number of ways in which similar structural domains can be generated in proteins by different amino acid sequences. By contrast, the structure of DNA, made up of only four different nucleotide building blocks that occur in two pairs, is relatively simple, regular, and predictable.
Biomolecular sequence alignment/string search is the most important …
An Investigation Of The Effect Of Sonic Frequency In The Removal Of Volatile Organic Compounds From Soils Using A Siren-Pneumatic Fracturing Coupled Technique, Chin-Yu Lin
Theses
This study investigates the effect of frequency from sonic energy coupled with soil fracturing for the removal of volatile organic compounds from low permeability soils. The laboratory experiments consisted of a test cell, 12 1/2 inches by 12 1/2 inches and 23 3/4 inches high, containing a 1/2 inch geotextile made to simulate the fracture. The pneumatic sound generator used was a siren type generator designed and built at NJIT.
Laboratory experiments were performed using the NJJT siren at frequencies of 2957, 6637, 10317, 13997 Hertz and baseline tests with no sound energy were also conducted. The free moisture …
Role Of Reactive Oxygen Species In Mercapto-Methylimidazole-Induced Gastric Acid Secretion And Stress-Induced Gastric Ulceration, Uday Bandyopadhyay, Dipak Das, Debasish Bandyopadhyay, Mrinalini Bhattacharjee, Ranajit K. Banerjee
Role Of Reactive Oxygen Species In Mercapto-Methylimidazole-Induced Gastric Acid Secretion And Stress-Induced Gastric Ulceration, Uday Bandyopadhyay, Dipak Das, Debasish Bandyopadhyay, Mrinalini Bhattacharjee, Ranajit K. Banerjee
School of Integrative Biological & Chemical Sciences (Formerly Dept. of Chemistry)
The objective of the present study is to delineate the role of reactive oxygen species in drug-induced gastric hyperacidity and stress-induced gastric ulceration. We reported earlier that mercaptomethylimidazole (MMI), an antithyroid drug, induces gastric acid (HCl) secretion partially through H2receptor activation of the parietal cell by histamine release and partially through an intracellular mechanism. While studying the latter, MMI-induced acid secretion was found to correlate well with the inactivation of the peroxidase, an important H2O2metabolizing enzyme of the mucosa. MMI activates the isolated parietal cell for acid secretion, which is sensitive to omeprazole. Peroxidase and catalase activity of the isolated …
Measuring Fractional Cover And Leaf Area Index In Arid Ecosystems: Digital Camera, Radiation Transmittance, And Laser Altimetry Methods, Michael A. White, Gregory P. Asner, Ramakrishna R. Nemani, Jeff L. Privette, Steven W. Running
Measuring Fractional Cover And Leaf Area Index In Arid Ecosystems: Digital Camera, Radiation Transmittance, And Laser Altimetry Methods, Michael A. White, Gregory P. Asner, Ramakrishna R. Nemani, Jeff L. Privette, Steven W. Running
United States National Aeronautics and Space Administration: Publications
Field measurement of shrubland ecological properties is important for both site monitoring and validation of remote sensing information. During the May 1997 NASA Earth Observing System Jornada Prototype Validation Exercise, we calculated plot-level plant area index, leaf area index, total fractional cover, and green fractional cover with data from four instruments: (1) a Dycam Agricultural Digital Camera (ADC), (2) a LI-COR LAI-2000 plant canopy analyzer, (3) a Decagon sunfleck Ceptometer, and (4) a laser altimeter. Estimates from the LAI-2000 and Ceptometer were very similar (plant area index 0.3, leaf area index 0.22, total fractional cover 0.19, green fractional cover 0.14), …
Water Quality In East Pond: Factors Contributing To Algal Blooms And Strategies For Remediation, Problems In Environmental Science Course (Biology 493), Colby College, Colby Environmental Assessment Team, Colby College
Water Quality In East Pond: Factors Contributing To Algal Blooms And Strategies For Remediation, Problems In Environmental Science Course (Biology 493), Colby College, Colby Environmental Assessment Team, Colby College
Colby College Watershed Study: East and North Ponds (2011, 1999, 1996, 1991)
Human activity within the watershed can greatly accelerate the eutrophication process by increasing the rate at which nutrients such as phosphorus and nitrogen enter the lake (Fernandez et al. 1992). Increased nutrient loading causes dramatic increases in algal populations resulting in algal blooms. Many New England lakes develop a greenish tint because of algal blooms during early summer or early fall (Smith, 1992). Populations of bacteria which feed on organic material rise because of increased food supply. Bacterial activity decreases the level of dissolved oxygen in the lake (Henderson-Seller and Markland, 1987). This process has occurred in East Pond and …
Time Delay In The Kuramoto Model Of Coupled Oscillators, Stephen M.K. Yeung, S H. Strogatz
Time Delay In The Kuramoto Model Of Coupled Oscillators, Stephen M.K. Yeung, S H. Strogatz
Mathematics
We generalize the Kuramoto model of coupled oscillators to allow time-delayed interactions. New phenomena include bistability between synchronized and incoherent states, and unsteady solutions with time-dependent order parameters. We derive exact formulas for the stability boundaries of the incoherent and synchronized states, as a function of the delay, in the special case where the oscillators are identical. The experimental implications of the model are discussed for populations of chirping crickets, where the finite speed of sound causes communication delays, and for physical systems such as coupled phase-locked loops or lasers.
Relationship Between Udp-Glucose 4-Epimerase Activity And Oligoglucose Glycoforms In Two Strains Of Neisseria Meningitidis, F K. Lee, B W. Gibson, William Melaugh, A Zaleski, M A. Apicella
Relationship Between Udp-Glucose 4-Epimerase Activity And Oligoglucose Glycoforms In Two Strains Of Neisseria Meningitidis, F K. Lee, B W. Gibson, William Melaugh, A Zaleski, M A. Apicella
Chemistry Faculty Publications
Sodium dodecyl sulfate-polyacrylamide gel analysis of lipooligosaccharide (LOS) from Neisseria meningitidis has demonstrated considerable microheterogeneity in the variable region of LOS due to the presence of novel glycoforms. As a step toward understanding the basis for the expression of these novel glycoforms, we have examined the LOS structures and UDP-glucose 4-epimerase (epimerase) activity levels in two strains (NMB and MA-1) and their respective galE mutants. Strain NMB was found to have low epimerase activity and to contain multiple glycoforms, some of which appear to contain only glucose sugars. The galE mutant had only the oligoglucose glycoforms. Strain MA-1 had higher …
Notes And Correspondence: The Effects Of Data Gaps On The Calculated Monthly Mean Maximum And Minimum Temperatures In The Continental United States: A Spatial And Temporal Study, David E. Stooksbury, Craig D. Idso, Kenneth G. Hubbard
Notes And Correspondence: The Effects Of Data Gaps On The Calculated Monthly Mean Maximum And Minimum Temperatures In The Continental United States: A Spatial And Temporal Study, David E. Stooksbury, Craig D. Idso, Kenneth G. Hubbard
School of Natural Resources: Faculty Publications
Gaps in otherwise regularly scheduled observations are often referred to as missing data. This paper explores the spatial and temporal impacts that data gaps in the recorded daily maximum and minimum temperatures have on the calculated monthly mean maximum and minimum temperatures. For this analysis 138 climate stations from the United States Historical Climatology Network Daily Temperature and Precipitation Data set were selected. The selected stations had no missing maximum or minimum temperature values during the period 1951–80. The monthly mean maximum and minimum temperatures were calculated for each station for each month. For each month 1–10 consecutive days of …
The Relative Importance Of Patch Area And Perimeter–Area Ratio To Grassland Breeding Birds, Christopher J. Helzer, Dennis E. Jelinski
The Relative Importance Of Patch Area And Perimeter–Area Ratio To Grassland Breeding Birds, Christopher J. Helzer, Dennis E. Jelinski
School of Natural Resources: Faculty Publications
Habitat fragmentation has been implicated as a major cause of population decline in grassland birds. We tested the hypothesis that a combination of area and shape determines the use of grassland patches by breeding birds. We compared both species richness and individual species presence in 45 wet meadow grasslands in the floodplain of the central Platte River, Nebraska. Bird data were collected through the use of belt transects and supplemented by walking and listening outside transects. Our data supported our primary hypothesis that perimeter–area ratio, which reflects both the area and shape of a patch, is the strongest predictor of …
Skeletal Architecture And Density Banding Analysis Technique For Diploria Strigosa By X-Ray Computed Tomography, Kevin P. Helmle, Richard E. Dodge (Editor)
Skeletal Architecture And Density Banding Analysis Technique For Diploria Strigosa By X-Ray Computed Tomography, Kevin P. Helmle, Richard E. Dodge (Editor)
Marine & Environmental Sciences Faculty Proceedings, Presentations, Speeches, Lectures
Coral skeletal density information is a useful growth parameter and may be coupled with extension rates to determine calcification rates. The conventional process for density determination is often cumbersome and requires some parameters which are difficult to precisely specify (e.g., Mass absorption coefficients). We have developed a technique and windows based computer program which enables the rapid collection of coral density data. The coral skeleton slab is xradiographed with an aluminum wedge. Thickness and density of the aluminum wedge, thickness of the coral slab, density of pure coral aragonite, and digitized images of the coral and wedge x-radiographs provide necessary …
Tracks To Therapy, Robert Katz, F. A. Cucinotta
Tracks To Therapy, Robert Katz, F. A. Cucinotta
Robert Katz Publications
Studies of the structure of particle tracks have led to models of track effects based on radial dose and radiobiological target theory that have been very successful in describing and predicting track effects in physical, chemical, and biological systems. For describing mammalian cellular inactivation two inactivation modes are required, called gamma-kill aid ion-kill, the first due to synergistic effects of delta rays from adjacent ion paths thus resembling the effects from gamma rays, and the second to the effects of single ion transits through a cell nucleus. The ion-kill effect is more severe, where the fraction of cells experiencing ion …
A New Model For Predicting Probabilities Of Viable Pregnancy And Multiple Gestations For I̲N̲ V̲I̲T̲R̲O̲ Fertilization, Ray Vernon Haning Jr.
A New Model For Predicting Probabilities Of Viable Pregnancy And Multiple Gestations For I̲N̲ V̲I̲T̲R̲O̲ Fertilization, Ray Vernon Haning Jr.
Theses, Dissertations and Capstones
In vitro fertilization (IVF) can be viewed as high stakes gambling with more than one winning outcome and more than one outcome leading to failure. Knowing the odds of successful outcomes, the odds of outcomes leading to failure, and the various costs is a tremendous asset in any form of gambling. Four important variables have been reported to affect pregnancy rates in IVF programs: age of patient, number of unsuccessful prior attempts, embryo morphology, and number of embryos transferred.
While it is desirable to optimize pregnancy rates, such optimization may often result in a high incidence of multiple gestation. Data …
Grazing Arizona: Public Land Management In The Southwest, Char Miller
Grazing Arizona: Public Land Management In The Southwest, Char Miller
Pomona Faculty Publications and Research
In February of 1999, the chief of the U.S. Forest Service, Michael Dombeck, placed a moratorium on road building on most roadless areas. In October, President Clinton put forth an initiative to prohibit road building on 40 million acres of roadless area. Such modifications in Forest Service land management decisions is not new as suggested by Char Miller in this look back at early grazing decisions by Pinchot. To be proactive and reactive at the same time in relation to changing social pressures and political realties may be the legacy of the agency.
Editorial Board & Iowa Academy Of Science Officers And Directors
Editorial Board & Iowa Academy Of Science Officers And Directors
Journal of the Iowa Academy of Science: JIAS
No abstract provided.
Symposia
Journal of the Minnesota Academy of Science
Abstracts from the Symposia Papers given at the 67th Annual Meeting for the Journal of the Minnesota Academy of Science.
Effect Of Human Disturbance On Small Mammal Communities In Itasca State Park, Minnesota, Nancy L. Staus, Kathleen Conforti, Leslie N. Clapper, Jennifer A. Longhenry, C. C. Schoenbauer, Michael S. Rentz, John R. Tester
Effect Of Human Disturbance On Small Mammal Communities In Itasca State Park, Minnesota, Nancy L. Staus, Kathleen Conforti, Leslie N. Clapper, Jennifer A. Longhenry, C. C. Schoenbauer, Michael S. Rentz, John R. Tester
Journal of the Minnesota Academy of Science
We determined effects of different levels of human disturbance on small mammal richness and relative abundance from live-trapping data obtained in Itasca State Park in northwestern Minnesota. We developed a quantitative measure of human disturbance based on disturbance units and trapped small mammals on three study sites, each reflecting a different level of disturbance. Our data revealed that small mammal diversity decreased with increasing human disturbance. Amount of ground cover and litter depth also appeared to be important in explaining differences in the demographic patterns of small mammals among sites.
The Role Of Trust In The North Blackforest: An Evaluation Of A Citizen Panel Project, Ragnar E. Löfstedt
The Role Of Trust In The North Blackforest: An Evaluation Of A Citizen Panel Project, Ragnar E. Löfstedt
RISK: Health, Safety & Environment (1990-2002)
Dr. Löfstedt explores the effectiveness of a public participation project conducted in Germany, designed to involve citizens in the siting of municipal waste disposal plants.
Oceanographic Center Catalog 1999-2000, Nova Southeastern University
Oceanographic Center Catalog 1999-2000, Nova Southeastern University
Halmos College of Natural Sciences and Oceanography Course Catalogs
No abstract provided.
Analysis Of Institutional Innovation In The Natural Resources And Environmental Realm: The Emergence Of Alternative Problem-Solving Strategies In The American West, Douglas S. Kenney, William B. Lord, University Of Colorado Boulder. Natural Resources Law Center
Analysis Of Institutional Innovation In The Natural Resources And Environmental Realm: The Emergence Of Alternative Problem-Solving Strategies In The American West, Douglas S. Kenney, William B. Lord, University Of Colorado Boulder. Natural Resources Law Center
Books, Reports, and Studies
x, 109 p. ; 28 cm
Book Review: Swallow Summer, Peter E. Lowther
Book Review: Swallow Summer, Peter E. Lowther
Journal of the Iowa Academy of Science: JIAS
Swallow Summer. Charles R. Brown. 1998. The University of Nebraska Press, Lincoln, NE. 371 pages. ISBN 0-8032-6145-4.
This book, Swallow Summer, is a popular account of the Browns fifteenth year at Cedar Point Biological Station in Keith County, Nebraska. Brown presents a daily log of the activities that he undertakes for the 1995 field season, describing the work supporting his research program. In the preface, Brown hopes Swallow Summer can explain his fascination with Cliff Swallows and why he enjoys his research. His intent is to describe "the challenges, thrills, and frustrations that come with studying wild animals in the …
Editorial Board & Iowa Academy Of Science Officers And Directors
Editorial Board & Iowa Academy Of Science Officers And Directors
Journal of the Iowa Academy of Science: JIAS
No abstract provided.
Morphology, Ultrastructure, And Function Of Extrafloral Nectaries In Three Species Of Caesalpiniaceae, Lenore T. Durkee, Matthew H. Haber, Lisa Dorn, Ann Remington
Morphology, Ultrastructure, And Function Of Extrafloral Nectaries In Three Species Of Caesalpiniaceae, Lenore T. Durkee, Matthew H. Haber, Lisa Dorn, Ann Remington
Journal of the Iowa Academy of Science: JIAS
Light and electron microscopy reveal that the morphologically well-differentiated petiolar nectaries of Chamaecrista fasciculata, Senna hepecarpa, and S. marilandica have an unusually simple anatomy consisting of an epidermis immediately subtended by a mass of small, loosely-packed parenchyma cells. Vascular strands from the petiolar bundles enter the nectary and terminate as phloem within or near this parenchyma. In mature, secreting nectaries, the cuticle of the epidermis extends between the epidermal cells and into the nectary parenchyma, where it occupies, but does not occlude, much of the free space of this tissue. The cutin is not found below the level …
Awards And Recognition, Iowa Academy Of Science, 1999
Awards And Recognition, Iowa Academy Of Science, 1999
Journal of the Iowa Academy of Science: JIAS
No abstract provided.
The Deconstruction Of Mathematics: A Criticism Of Reuben Hersh's What Is Mathematics, Really? And The Humanist Philosophy Of Mathematics, David J. Stucki
The Deconstruction Of Mathematics: A Criticism Of Reuben Hersh's What Is Mathematics, Really? And The Humanist Philosophy Of Mathematics, David J. Stucki
Mathematics Faculty Scholarship
Mathematics, as an academic discipline, has stood for many years as the last bastion against a growing tide of intellectual relativism that has become all but ubiquitous. More recently, however, efforts have been made to "humanize" mathematics by advocating a social-constructivist approach to the philosophy of mathematics, both in practice and education. This paper is intended to serve as a critical response to one advocate of this approach, Reuben Hersh (What Is Mathematics, Really?, 1997), and in the process a defense of Platonism.