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Population Dynamics And Harvest Response Of Beaver, Neil F. Payne Sep 1989

Population Dynamics And Harvest Response Of Beaver, Neil F. Payne

Eastern Wildlife Damage Control Conference: 4th (1989)

"For when we speak of the fur trade, we mean the beaver trade. Other furs were handled; others — notably the rich sea otter — were more valuable by far. But the beaver was the root and core of the trade ... Many men died, a continent was explored, an indigenous [human] race degraded and its culture crushed; all because beaver fur, with its tiny barbs, felted up better than any other" (Berry 1961:18).

The habits of beaver (Castor canadensis) allow them to be located and trapped readily, resulting in their extirpation from many areas. Beaver populations have …


Fertility Control As A Tool For Regulation Of Wildlife Populations, U.S. Seal Sep 1989

Fertility Control As A Tool For Regulation Of Wildlife Populations, U.S. Seal

Eastern Wildlife Damage Control Conference: 4th (1989)

Biological control of reproduction and fertility is a normal part of the life history of all organisms. Control mechanisms allow timing of reproduction with respect to age, time of day, season, and other periodic environmental events. Further modulation can occur with variations in temperature, rainfall, nutrition, and health status. Interactions with other members of the species, ranging from pherohormonal stimulation of estrus to social delay of puberty and breeding to infanticide, provide further constraints upon fertility and recruitment. All of these processes ultimately act through molecular neuroendocrine mechanisms that are under genetic control and are subject to natural selection and …


An Analysis Of The Water Situation In The United States: 1989-2040, Richard W. Guldin, Usda Forest Service Sep 1989

An Analysis Of The Water Situation In The United States: 1989-2040, Richard W. Guldin, Usda Forest Service

All U.S. Government Documents (Utah Regional Depository)

Several Federal agencies have historically had responsibilities for conducting assessments of the Nation's water resources. The U.S. Geological Survey (USGS), U.S. Army Corps of Engineers, U.S. Department of Agriculture's Soil Conservation Service (SCS), and U.S. Environmental Protection Agency (EPA) and its predecessor agencies, among others, have conducted studies assessing the current situation and future prospects for water in particular regions of the country. Responsibility for national water assessments was assigned to the U.S. Water Resources Council (WRC) by the Water Resources Planning Act of 1965. With the demise of the WRC in 1981, several member agencies have attempted to take …


Biological Reductive Dechlorination Of Tetrachloroethylene And Trichloroethylene To Ethylene Under Methanogenic Conditions, David L. Freedman, James M. Gossett Sep 1989

Biological Reductive Dechlorination Of Tetrachloroethylene And Trichloroethylene To Ethylene Under Methanogenic Conditions, David L. Freedman, James M. Gossett

Publications

A biological process for remediation of groundwater contaminated with tetrachloroethylene (PCE) and trichloroethylene (TCE) can only be applied if the transformation products are environmentally acceptable. Studies with enrichment cultures of PCE- and TCE-degrading microorganisms provide evidence that, under methanogenic conditions, mixed cultures are able to completely dechlorinate PCE and TCE to ethylene, a product which is environmentally acceptable. Radiotracer studies with [14C]PCE indicated that [14C]ethylene was the terminal product; significant conversion to 14CO2 or 14CH4 was not observed. The rate-limiting step in the pathway appeared to be conversion of vinyl chloride to ethylene. To sustain reductive dechlorination of PCE and …


Water Current, Volume 21, September 1989 Sep 1989

Water Current, Volume 21, September 1989

Water Current Newsletter

United Nations Association, Nebraska Division Hears Roger Gold's "World's Water Problems"
Groundwater--One Word or Two?
Sandhills Water Resources and Irrigation Observed on Annual Nebraska Tour
Survey Reveals Recreational Activities of Nebraskans
Farm Conservation and Water Protection Act of 1989
New Staff at Water Center
Colorado State Receives $9 Million for Somalian Water Management Project
EPA Announces Third Method to Determine Drinking Water Coliforms
NRD History and Mission Explained in Booklet Now Available to Public
White House Conference on Water Resources Proposed by NWA to Discuss Water Issues
Acid Rain International Problem; Midwest's Too
Deadline for Grant Proposals to USGS Announced …


Particle Tracks In Diverse Media, Robert Katz Sep 1989

Particle Tracks In Diverse Media, Robert Katz

Robert Katz Publications

When energetic heavy ions pass into a medium, they create a trail of excitations, ionizations, and secondary electrons whose effect is represented through their average radial “dose” distribution. The structure of the track depends on this and on the observed “end point.” Tracks may be observed microscopically or through the gross effect of a particle beam. We take the medium to be an assemblage of “targets” whose response to gamma rays is approximated by the cumulative Poisson distribution. While most detectors are 1-hit systems, we have discovered 2-hit and up to 8-hit response. Folding the gamma-ray response into the radial …


The Prairie Naturalist Volume 21, No.3 September 1989 Sep 1989

The Prairie Naturalist Volume 21, No.3 September 1989

The Prairie Naturalist

SEED DISPERSAL CHARACTERISTICS OF PLAINS SILVER SAGEBRUSH ▪ C. L. Wambolt, T. Walton, and R. S. White

ON THE TRAIL OF THE ANT, VEROMESSOR LOBOGNATHUS . ▪ G. C. Wheeler and J. Wheeler

LAND USE RELATIONSHIPS TO AVIAN CHOLERA OUTBREAKS IN THE NEBRASKA RAINWATER BASIN AREA ▪ B. J. Smith, K. F. Higgins, and C. F. Gritzner

INCIDENCE OF LEAD SHOT IN THE RAINWATER BASINS OF SOUTH CENTRAL NEBRASKA ▪ . D. W. Oates

REPRODUCTION, RECRUITMENT, AND SURVIVAL OF BROWN AND RAINBOW TROUT IN A PRAIRIE COTEAU STREAM ▪ C. L. Milewski and D. W. Willis

SIZE STRUCTURE AND CATCH …


Hplc Analysis Of Pah And Selected Substituted Derivatives In Waste Incinerator Emission Particles. Section I. Analysis Of Uptake Of Bap By Earthworms Living In Bap-Contaminated Soils. Section Ii, Chin-Fang Juang Aug 1989

Hplc Analysis Of Pah And Selected Substituted Derivatives In Waste Incinerator Emission Particles. Section I. Analysis Of Uptake Of Bap By Earthworms Living In Bap-Contaminated Soils. Section Ii, Chin-Fang Juang

Theses

Polycyclic aromatic hydrocarbons ( PAH ) are quite persistent and some of them are potent carcinogens in mammals. They have been found in many environmental media including air, water, soil, fly ash, sediment, sewage sludge, food and plants. This thesis is a study of PAH sampled from incinerator emissim particulates, air, soil, and earthworms raised in artificially contaminated soil.

In Section I, a method is described for the analysis of PAH, nitro-PAH and quinones extracted from filters and detected by HPLC. They were collected on particulate filters which were sampled using the EPA Modified Method 5 regime from incinerator emissions. …


Phase I - Preconstruction Progress Report For Biological Monitoring Of The John U. Lloyd Beach Renourishment, Richard E. Dodge, Steven C. Hess, Charles G. Messing, Glenda Kelley Aug 1989

Phase I - Preconstruction Progress Report For Biological Monitoring Of The John U. Lloyd Beach Renourishment, Richard E. Dodge, Steven C. Hess, Charles G. Messing, Glenda Kelley

Marine & Environmental Sciences Faculty Reports

In 1987, Nova University (Contractor) with ERM South (Subcontractor) was awarded a contract to provide biological monitoring services for the John U. Lloyd State Recreation Area Beach Renourishment Project. A notice to proceed for the initial biological monitoring (phase I - Preconstruction) was issued in February, 1989. Field monitoring took place in February and March, 1989. Laboratory work has continued from March, 1989 to present. The renourishment dredging took place from May 16, 1989 to July 14, 1989. Approximately 603,000 cu yds of sediment were removed and subsequently emplaced on 1.6 miles of shoreline. Within the next 6 months, Broward …


Quantitative Footprinting Analysis. Binding To A Single Site, Robert Rehfuss, Jerry Goodisman, James C. Dabrowiak Aug 1989

Quantitative Footprinting Analysis. Binding To A Single Site, Robert Rehfuss, Jerry Goodisman, James C. Dabrowiak

Chemistry - All Scholarship

The theory for measuring ligand binding constants from footprinting autoradiographic data associated with a single binding site is derived. If the ligand and DNA cleavage agent compete for a common site, the spot intensities are not proportional to the amount of DNA not blocked by ligand. The analysis of a single site is experimentally illustrated by using results for the anticancer drug actinomycin D interacting with the duplex d(TAGCGCTA)2 as probed with the hydrolytic enzyme DNase I.


The Response Of The Alanine Detector After Charged-Particle And Neutron Irradiations, M. P. R. Waligorski, G. Danialy, Robert Katz Aug 1989

The Response Of The Alanine Detector After Charged-Particle And Neutron Irradiations, M. P. R. Waligorski, G. Danialy, Robert Katz

Robert Katz Publications

Radiosensitivity parameters of track structure theory, representing alanine as a one-hit detector, have been fitted for this free-radical amino-acid system on the basis of the available experimental data on the relative effectiveness of alanine after charged particle and neutron irradiations. The experimental data set can be reproduced by theoretical calculations, roughly to within experimental accuracy. A charged-particle “equivalent radiation” is introduced which can mimic the response of alanine to neutron irradiations. Implications of the results of model calculations for alanine on the shape of the radial distribution of δ-ray dose postulated by track theory, are discussed.


Photocycloaddition Of 4,5',8-Trimethylpsoralen And Oleic Acid Methyl Ester: Product Structures And Reaction Mechanism, Kathleen G. Specht, W. Robert Midden, Miles R. Chedekel Aug 1989

Photocycloaddition Of 4,5',8-Trimethylpsoralen And Oleic Acid Methyl Ester: Product Structures And Reaction Mechanism, Kathleen G. Specht, W. Robert Midden, Miles R. Chedekel

Chemistry Faculty Publications

The stereochemical structures of the four adducts formed between oleic acid methyl ester (OAME) and 4,5',8-trimethylpsoralen (tmPso) have been determined. Assignment of the tmPso 'H NMR spectrum was accomplished by analogy to two coumarin model compounds and with the use of homonuclear decoupling and resonance enhancement. Assignment of the lH NMR spectra for the OAME-tmPso adducts was made by analogy to the spectra of OAME and tmPso and using 2D &resolved and COSY analyses. The configurations of the cyclobutyl rings in these adducts was determined by The stereochemical structures of the four adducts formed between oleic acid methyl ester (OAME) …


Effect Of Photoperiod On Developmental Morphology And Enolase Isoenzyme Immunohistochemistry In Rat And Djungarian Hamster Superficial Pineal Glands, Chalmer D. Mcclure Aug 1989

Effect Of Photoperiod On Developmental Morphology And Enolase Isoenzyme Immunohistochemistry In Rat And Djungarian Hamster Superficial Pineal Glands, Chalmer D. Mcclure

Loma Linda University Electronic Theses, Dissertations & Projects

The best understood functional activity of the pineal gland is its diurnal production of melatonin in response to environmental lighting cues. Several enzymes of the melatonin pathway respond to daily photoperiod changes, for example hydroxyindole-O-methyltransferase (HIOMT) and serotonin N-acetyltransferase (SNAT). Increased levels of the glycolytic enzyme neuron-specific enolase (NSE) are thought to reflect increased physiological demands placed on neurons and neuroendocrine tissues. Homodimer non-neuronal enolase isoenzyme (NNE) is immunolocalized to cells, and the hybrid enolase (consisting of subunits from NSE and NNE) has been seen in cerebellar stellate and basket cells. Although not rate limiting, concentrations of both NSE and …


Department Of Fisheries Annual Report 1988/89, Department Of Fisheries, Western Australia Aug 1989

Department Of Fisheries Annual Report 1988/89, Department Of Fisheries, Western Australia

Department of Fisheries Annual Reports

In accordance with Section 62 of the Financial Administration and Audit Act 1985, I submit for your information and presentation to Parliament the Annual Report of the Fisheries Department for the financial year ending 30 June 1989.

The Annual Report has been prepared in accordance with the provisions of the Financial Administration and Audit Act 1985.

Section 57 of the Fisheries Act 1905 requires me to report to you as to the state of the fisheries of the State and for such report to be laid before both Houses of Parliament


Wetland Study Of Southeastern Portage Township, Kalamazoo County, Michigan, Kevin M. Walsh Aug 1989

Wetland Study Of Southeastern Portage Township, Kalamazoo County, Michigan, Kevin M. Walsh

Masters Theses

Under the Clean Water Act, Congress passed legislation to maintain and restore the chemical, physical, and biological integrity of the water of the United States. The objective of this study is to determine if the wooded area located in Upjohn Company's Property in southeastern Portage Township, Portage, Michigan falls under the classification of a wetland.

This objective has been pursued through an examination of the hydrology of the area, the soil characteristics of the area, and the vegetation types and characteristics of the area. These parameters have been utilized following the guidelines outlined in the "Corps of Engineers Wetland Delineation …


Bioremediation Of Contaminated Surface Soils, J. L. Sims, R. C. Sims, J. E. Matthews Aug 1989

Bioremediation Of Contaminated Surface Soils, J. L. Sims, R. C. Sims, J. E. Matthews

Reports

Biological remediation of soils contaminated with organic chemicals is an alternative treatment technology that can often meet the goal of achieving a permanent clean-up remedy at hazardous waste sites, as encouraged by the U.S. Environmental Protection Agency (U.S. EPA) for implementation of The Superfund Amendments and Authorization Act (SARA) of 1986. Bioremediation is consistent with the philosophical thrust of SARA, for it involves the use of naturally occurring microorganisms to degrade and/or detoxify hazardous constituents in the soil at a contaminated slip to protect public health and the environment.Bioremediation of contaminated soils, including applications and limitations, has been addressed.


Santa Clara Magazine, Volume 31 Number 4, Summer 1989, Santa Clara University Jul 1989

Santa Clara Magazine, Volume 31 Number 4, Summer 1989, Santa Clara University

Santa Clara Magazine

10 - COMPETITION AND CHANGE The way we organize human affairs is undergoing its most profound transformation in 2,000 years. By Thomas J. Peters

15 - WHAT'S A CHRISTIAN FAMILY TO DO? Some practical suggestions on family life in today's too busy world. By Mitch Finley '73

18 - REFLECTIONS OF A JESUIT'S EARLY YEARS Santa Clara's former president writes movingly of his experiences as a Jesuit novice. By William J. Rewak, SJ.

24 - A TOUCH OF WRY B.T. Collins '70 is an outrageously funny man who just can't seem to leave politics alone. By Barbara Wyman

28 - …


Testing Macroevolutionary Hypotheses With Cladistic Analysis: Evidence Against Rectangular Evolution, Cliff A. Lemen, Patricia W. Freeman Jul 1989

Testing Macroevolutionary Hypotheses With Cladistic Analysis: Evidence Against Rectangular Evolution, Cliff A. Lemen, Patricia W. Freeman

School of Natural Resources: Faculty Publications

The properties of cladistic data sets from small monophyletic groups (6-1 2 species) are investigated using computer simulations of macroevolution. Two evolutionary models are simulated: gradualism and the punctuated-equilibrium hypothesis. Under the conditions of our simulations these two models of evolution make consistently different predictions about the distribution of autapomorphies among species. When strict stasis is enforced, the punctuated-equilibrium hypothesis predicts that the most expected number of autapomorphies per species will be zero, no matter how many characters are used in the analysis. As the number of characters used in the analysis increases, the distribution of the number of autapomorphies …


Mounting Sex Pheromone: A Novel Pheromone Responsible For Mate Recognition In The Ixodidae, Jgc Hamilton Jul 1989

Mounting Sex Pheromone: A Novel Pheromone Responsible For Mate Recognition In The Ixodidae, Jgc Hamilton

Theses and Dissertations in Biomedical Sciences

Cholesterol oleate was demonstrated to be the cuticular contact sex pheromone of Dermacentor variabilis. This pheromone which has been termed the Mounting Sex Pheromone (MSP) was also demonstrated to be present on the surface of D. andersoni, Amblyomma maculatum and A. americanum. This contact sex pheromone enables males excited and attracted by 2,6-dichlorophenol to identify the female as a potential mating partner. The MSP is the second in the series of three sex pheromones guiding the hierarchy of behavioral responses which constitute tick courtship behavior. Tests with D. variabilis and D. andersoni showed that this pheromone …


Mathematical Models Of Prevascular Tumor Growth By Diffusion, Sophia A. Maggelakis Jul 1989

Mathematical Models Of Prevascular Tumor Growth By Diffusion, Sophia A. Maggelakis

Mathematics & Statistics Theses & Dissertations

A study of several complementary mathematical models that describe the early, prevascular stages of solid tumor growth by diffusion under various simplifying assumptions is presented. The advantage of these models is that their degree of complexity is relatively low, which ensures fairly straightforward comparisons with experimental or clinical data (as it becomes available), yet they are mathematically sophisticated enough to capture the main biological phenomena of interest.

The tumor growth and cell proliferation rate are assumed to depend on the local concentrations of nutrients and inhibitory factors. The effects of geometry and spatially non-uniform inhibitor production and non-uniform nutrient consumption …


The Remipedia (Crustacea): A Study Of Their Reproduction And Ecology, Jill Yager Jul 1989

The Remipedia (Crustacea): A Study Of Their Reproduction And Ecology, Jill Yager

Biological Sciences Theses & Dissertations

Remipedes are an unusual group of troglobitic crustaceans that live exclusively in anchialine caves. Since their discovery in 1979, nine species have been described, seven of which are found in caves in the West Indies, one from the Yucatan peninsula of Mexico and one from the Canary Islands. Most of what is known about these animals has come mainly from taxonomic descriptions. Little has been published about their reproductive biology or ecology. The objectives of this dissertation were to investigate the reproductive biology and ecology of the remipedes inhabiting Sagittarius Cave on Grand Bahama Island, Bahamas.

Sagittarius Cave was chosen …


Picoplankton/Phytoplankton Dynamics In Hampton Roads, Virginia, Leslie E. Dorworth Jul 1989

Picoplankton/Phytoplankton Dynamics In Hampton Roads, Virginia, Leslie E. Dorworth

OES Theses and Dissertations

The biomass distribution of the three main size components of the phytoplankton (net, nano, and picoplankton) was examined in the lower Chesapeake Bay. Work was done at two stations during the spring and neap tidal cycles when freshwater flow into the bay was at its seasonal minimum and maximum. Emphasis was placed on how the picoplankton ( < 2.0 μm, > 0.2 μm) reacted during the sampling period.

Picoplankton made up approximately 13% of the total biomass, during the observed time period, at the more oceanic station. The picoplankton fraction contributed up to 16% of the total biomass at the estuarine station. From this …


The Temporal And Spatial Distribution Of Blue Crab Larvae On The Mid-Atlantic Bight Adjacent To The Chesapeake Bay, 1982-1983, Lyle Michael Varnell Jul 1989

The Temporal And Spatial Distribution Of Blue Crab Larvae On The Mid-Atlantic Bight Adjacent To The Chesapeake Bay, 1982-1983, Lyle Michael Varnell

OES Theses and Dissertations

Recruitment processes are important information for the management of commercially and recreationally exploited marine species. Recruitment processes of the Chesapeake Bay's most important commercial and recreational species, the blue crab, are unknown, due in part to the lack of knowledge of the processes directly preceeding recruitment.

The present study was undertaken to investigate and explain the movement and developmental patterns of blue crab larvae while offshore. Interannual and intraseasonal variations of these patterns were also examined.

Sampling occurred from May to November during 1982 and 1983. Larvae were collected at three depths (neuston layer (upper 10 cm), one meter and …


Simultaneous Determination Of 3-Methoxy-4-Hydroxyphenyl-Glycol, Homovanillic Acid, And 5-Hydroxyindoleacetic Acid In Plasma By High Performance Liquid Chromatography, Yung-Te Tseng Jul 1989

Simultaneous Determination Of 3-Methoxy-4-Hydroxyphenyl-Glycol, Homovanillic Acid, And 5-Hydroxyindoleacetic Acid In Plasma By High Performance Liquid Chromatography, Yung-Te Tseng

Chemistry & Biochemistry Theses & Dissertations

A rapid, reliable, and sensitive method for simultaneous determination of 3-methoxy-4-hydroxyphenylglycol (MHPG), Homovanillic acid (HVA), and 5-hydroxyindoleacetic acid (5- HIAA) in plasma is described. The method is based on high performance liquid chromatography with electrochemical detection. Samples were filtered with Amicon Centrifree micropartition systems and extracted with organic solvent before chromatography. Chromatographic separation of sample components was achieved isocratically in a C18 reverse-phase column. Quantitation was performed by measuring the peak height ratios of the sample components to an internal standard. Analytical recoveries ranged from 50.78 (SD 4.2%) to 67.94 (SD 3.28). Within-run coefficient of variations (CVs) ranged from 3.78 …


A Comparison Of Magnetite Particles Produced Anaerobically By Magnetotactic And Dissimilatory Iron‐Reducing Bacteria, Bruce M. Moskowitz, Richard B. Frankel, Dennis A. Bazylinski, Holger W. Jannasch, Derek R. Lovley Jul 1989

A Comparison Of Magnetite Particles Produced Anaerobically By Magnetotactic And Dissimilatory Iron‐Reducing Bacteria, Bruce M. Moskowitz, Richard B. Frankel, Dennis A. Bazylinski, Holger W. Jannasch, Derek R. Lovley

Physics

We compare the magnetic properties of fine‐grained magnetite produced by two newly isolated anaerobic bacteria, a magnetotactic bacterium (MV‐1) and a dissimilatory iron‐reducing bacterium (GS‐15). Although room‐temperature magnetic properties are generally different between the two microorganisms, MV‐1 and GS‐15 magnetites can be most easily distinguished by the temperature variation of saturation remanence obtained at liquid helium temperatures. Magnetite produced by MV‐1 displays a sharp discontinuity in intensity at 100 K related to the Verwey transition. Magnetite produced by GS‐15 displays a gradual decrease in intensity with temperature due to the progressive unblocking of magnetization. The differing behavior is due exclusively …


State Of The Fisheries Report 1988, Fisheries Department Of Western Australia Jun 1989

State Of The Fisheries Report 1988, Fisheries Department Of Western Australia

Status Reports of the Fisheries and Aquatic Resources

The State of the Fisheries is published annually by the Fisheries Department as part of the statutory reporting process required under the Fisheries Act. This report covers developments and production in the State's fisheries up to the end of December 1988. Full details of the department's operations for this period are published separately in the department's annual reports for the financial years ending June 1988 and 1989. Figures provided in the tables are derived from catch returns completed by fishermen which are processed by the Australian Bureau of Statistics. Other information provided in the text comes from research programs conducted …


Within The Hundredth Meridian: Western States And Their River Basins In A Time Of Transition, John M. Volkman, Kai N. Lee Jun 1989

Within The Hundredth Meridian: Western States And Their River Basins In A Time Of Transition, John M. Volkman, Kai N. Lee

Boundaries and Water: Allocation and Use of a Shared Resource (Summer Conference, June 5-7)

29 pages.

Contains footnotes.


Interjurisdictional Relations Under Federal Water Quality Law: A Guide Through The Maze, Michael C. Blumm, Daniel Rohlf Jun 1989

Interjurisdictional Relations Under Federal Water Quality Law: A Guide Through The Maze, Michael C. Blumm, Daniel Rohlf

Boundaries and Water: Allocation and Use of a Shared Resource (Summer Conference, June 5-7)

53 pages.

Contains references.


The Colorado River Compact: A Breeding Ground For International, National, And Interstate Controversies, John U. Carlson Jun 1989

The Colorado River Compact: A Breeding Ground For International, National, And Interstate Controversies, John U. Carlson

Boundaries and Water: Allocation and Use of a Shared Resource (Summer Conference, June 5-7)

38 pages.

Contains references.


Interstate Allocation Of The Platte River, J. David Aiken Jun 1989

Interstate Allocation Of The Platte River, J. David Aiken

Boundaries and Water: Allocation and Use of a Shared Resource (Summer Conference, June 5-7)

27 pages.

Contains references.