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The Occurrence Of Fish Remains In Modern Lake Systems : A Test Of The Stratified-Lake Mode, Douglas R. Britton Jun 1988

The Occurrence Of Fish Remains In Modern Lake Systems : A Test Of The Stratified-Lake Mode, Douglas R. Britton

Loma Linda University Electronic Theses, Dissertations & Projects

Theories regarding the taphonomy of fishes in lacustrine environments have traditionally relied on an anoxic water column to explain the excellent preservation. This concept has never been directly tested in modern lacustrine environments that are thought to be analogous to the lacustrine environments predicted by the Stratified-lake Model. This research tested that model by searching for fish remains in 38 collected bottom samples of six modern lacustrine analogues, including Fayetteville Green Lake, New York. The bottom sediments of a warm, holomictic, shallow, and saline lake (Salton Sea, California) were also examined. Although laminated sediments were found in all of the …


Characterization Of The Aquatic Environment In Lake Mead Near The Proposed Spring Canyon Pumped-Storage Project, And Assessment Of Potential Aquatic Impacts, Charles R. Liston, Stephen J. Grabowski, Bureau Of Reclamation Jun 1988

Characterization Of The Aquatic Environment In Lake Mead Near The Proposed Spring Canyon Pumped-Storage Project, And Assessment Of Potential Aquatic Impacts, Charles R. Liston, Stephen J. Grabowski, Bureau Of Reclamation

Publications (WR)

A pumped storage system consists of an upper reservoir and lower reservoir separated by an elevation difference. During low demand energy periods such as nights and weekends water is pumped from the lower to the upper reservoir using available energy from conventional steam electric power plants. During high energy demand periods, such as mornings and afternoons of weekdays, upper reservoir water is allowed to drop back down through the same system of water conduits and turbines, generating electricity to conveniently meet abrupt electrical energy requirements. The same water turbines thus act both as pumps and as conventional hydroelectric turbines. Because …


Callianassa Trilobata (Crustacea: Thalassinidea) Influences Abundance Of Meiofauna And Biomass, Composition, And Physiologic State Of Microbial Communities Within Its Burrow, Fred C. Dobbs, James B. Guckert Jun 1988

Callianassa Trilobata (Crustacea: Thalassinidea) Influences Abundance Of Meiofauna And Biomass, Composition, And Physiologic State Of Microbial Communities Within Its Burrow, Fred C. Dobbs, James B. Guckert

OES Faculty Publications

Biochemical and traditional methods were used to determine the influence of Callianassa trilobata on microbiological and meiofaunal communities within its large, highly consolidated burrow. Sediment was collected from the lining of the shrimp's burrow, the burrow matrix, and ambient, subsurface sediment. The lining and matrix were composed of poorly sorted, fine-grained material compared to sandy ambient sediment. Meiofauna, predominantly nematodes, were most abundant in ambient sediment, not in the burrow as has been found for other species of macrofauna. Concentrations of chlorophyll a were very high in the lining, consistent with the suggestion that C. trilobata lines its burrow walls …


Microbial Food Resources Of The Macrofaunal-Deposit Feeder Ptychodera Bahamensis (Hemichordata: Enteropneusta), Fred C. Dobbs, James B. Guckert Jun 1988

Microbial Food Resources Of The Macrofaunal-Deposit Feeder Ptychodera Bahamensis (Hemichordata: Enteropneusta), Fred C. Dobbs, James B. Guckert

OES Faculty Publications

Biochemical and traditional analyses were used to characterize the microbial food resources and digestive efficiency of Ptychodera bahamensis, an enteropneust hemichordate. Sediment was collected from freshly extruded fecal casts and adjacent feeding depressions. There were no significant differences between casts and depressions in median grain size, percent silt-clay, density of total meiofauna and of nematodes, and concentrations of chlorophyll a and phaeophytin. Nematodes in casts had a median diameter greater than those in depressions. Measures of total, viable microbial biomass were 30% (total phospholipid, ester-linked fatty acids) and 49% (extractible phospholipid phosphate) lower in casts. Concentrations of 33 fatty …


Pentachlorophenol And Oxygen Consumption Of Immobilized Mixed Bacterial Culture, Tesfamariam Stephanos Tsadwa May 1988

Pentachlorophenol And Oxygen Consumption Of Immobilized Mixed Bacterial Culture, Tesfamariam Stephanos Tsadwa

Theses

This study was undertaken to investigate the effects of Pentachlorophenol (PCP) concentration on oxygen consumption of immobilized microbial cells. The microbial population, from a municipal wastewater treatment plant, was immobilized in calcium alginate gel. The following studies have also been conducted in this project:

  1. Comparison of the effect of PCP concentration on oxygen uptake between immobilized and free cells.
  2. Comparison of the effects of PCP concentration on oxygen uptake between acclimated and an unacclimated bacterial beads.

Dissolved oxygen concentration was monitored using a flow Clark-type oxygen probe, in a micro-assay bioreactor. It was found that PCP concentrations higher than 2000ppm …


Use Of Economic Instruments In Biodiversity Conservation Projects: The Sustainability Of Projects In The Ecuadorian Amazon, Amy Lyons May 1988

Use Of Economic Instruments In Biodiversity Conservation Projects: The Sustainability Of Projects In The Ecuadorian Amazon, Amy Lyons

Honors Theses

Under what conditions do biodiversity conservation projects that use economic incentives promote the most significant and sustainable biodiversity protection? The study of how nations can best invest their resources to promote conservation while simultaneously encouraging a sustainable form of economic development has recently become a major focus for ecologically rich, less-developed countries. There have been many innovative and successful attempts at combining biodiversity protection with economic development, and others that have done more harm than good. Since there is no guaranteed recipe for a successful project, it is crucial to examine projects in detail to discern which type of project …


Problems And Opportunities For The Republic Of China In Regard To Distant Water Tuna Fisheries, Chih-I Sha May 1988

Problems And Opportunities For The Republic Of China In Regard To Distant Water Tuna Fisheries, Chih-I Sha

Marine Affairs Theses and Major Papers

The extension of fishery jurisdiction out to 200 miles from the baselines used to measure the territorial sea by most of the coastal states was the dominant event in global fisheries during the decade of the 1970s. In principle, under extended jurisdiction, the coastal states have the authority to eliminate economic waste and to reduce excessive fishing pressure; on the other hand, the distant water fishing states will have to curtail their fishing activities from the traditional fishing grounds off the coastal states. The Republic of China is a typical distant water fishing state, and is seriously impacted by the …


Water Current, Volume 20, May 1988 May 1988

Water Current, Volume 20, May 1988

Water Current Newsletter

Major Changes in Water Center During Past Nine Years
Water Law Expert Says Policies May Cause Pollution
Director's Report, A Glance Back
On the Other End of the Phone
Sheffield Announces Tours for July and September
Annual Awards Presented at Banquet
Water Resources Program Will Study Impact of Water Quality Legislation
Change Called for at Nebraska Water Conference
Nitrate Exposure Impacts Prenatal Mortality in Beef Cattle


Relocation Movement In A Stalked Crinoid (Echinodermata), Charles G. Messing, M. Christine Rosesmyth, Stuart R. Mailer, John E. Miller May 1988

Relocation Movement In A Stalked Crinoid (Echinodermata), Charles G. Messing, M. Christine Rosesmyth, Stuart R. Mailer, John E. Miller

Marine & Environmental Sciences Faculty Articles

No abstract provided.


The Probe, Issue 83 - May 1988 May 1988

The Probe, Issue 83 - May 1988

The Probe: Newsletter of the National Animal Damage Control Association

GOODBYE STRYCHNINE

NO ROOM FOR CATS

PESTICIDE TOXICITY

Texas Seminar

Sugar-Coating the Bear Problem

Letters to Ye Ed

Tn. Wildlife Soc. Hilites


A Cytochemical Study Of The Transcriptional And Translational Regulation Of Nuclear Transition Protein 1 (Tp1), A Major Chromosomal Protein Of Mammalian Spermatids, Mohammad A. Heidaran, Richard M. Showman, Wilson Stephen Kistler May 1988

A Cytochemical Study Of The Transcriptional And Translational Regulation Of Nuclear Transition Protein 1 (Tp1), A Major Chromosomal Protein Of Mammalian Spermatids, Mohammad A. Heidaran, Richard M. Showman, Wilson Stephen Kistler

Faculty Publications

Immunocytochemical localization and in situ hybridization techniques were used to investigate the presence of spermatid nuclear transition protein 1 (TP1) and its mRNA during the various stages of spermatogenesis in the rat. A specific antiserum to TP1 was raised in a rabbit and used to show that TP1 is immunologically crossreactive among many mammals including humans. During spermatogenesis the protein appears in spermatids as they progress from step 12 to step 13, a period in which nuclear condensation is underway. The protein is lost during step 15. An asymmetric RNA probe generated from a TP1 cDNA clone identified TP1 mRNA …


Structure-Activity Relationships Of Retinoids In Developmental Toxicology, W. Brian Howard May 1988

Structure-Activity Relationships Of Retinoids In Developmental Toxicology, W. Brian Howard

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The teratogenic potency of retinoid analogs was determined in Syrian hamsters and compared to the teratogenic potency of all-trans-retinoic acid (all-trans-RA, ED50 = 10.5 mg/kg). A total of 15 analogs having variations in the cyclohexene ring were evaluated following various amounts of single oral doses on day 8 of gestation. Retinoids containing a five- or six-membered ring were as teratogenic as all-trans-RA, provided they had sufficient lipophilic substituents on the ring. The same pattern emerged for retinoids that had six-membered aromatic ring substitution for the natural cyclohexene ring of vitamin A. Incorporation of a supplementary …


Interactions Of Vanadium Compounds With Reducing Equivalents: Evidence Of Free Radical Involvement And Possible Mechanisms Of Toxicity, Randal J. Keller May 1988

Interactions Of Vanadium Compounds With Reducing Equivalents: Evidence Of Free Radical Involvement And Possible Mechanisms Of Toxicity, Randal J. Keller

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Vanadium compounds have been reported to cause numerous toxicological effects including NAD(P)H oxidation and lipid peroxidation. The purpose of this thesis is to determine the active form of vanadium in causing these effects, and to determine any possible free radical involvement in these processes. Vanadium-stimulated oxidation of NADH was studied spectrophotometrically and by electron spin resonance spectroscopy. In 25 mM sodium phosphate buffer at pH 7. 4, vanadyl, (V(IV)), is slightly more effective in stimulating NADH oxidation than was vanadate (V(V)). Addition of a superoxide generating system, xanthine/xanthine oxidase, results in a marked increase in NADH oxidation by vanadyl, and …


A Model Of Energy Expenditure In White-Tailed Jackrabbits (Lepus Townsendii) Based On Integrated Studies Of Energetics And Field Ecology, Gordon L. Rogowitz May 1988

A Model Of Energy Expenditure In White-Tailed Jackrabbits (Lepus Townsendii) Based On Integrated Studies Of Energetics And Field Ecology, Gordon L. Rogowitz

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Field and laboratory studies were conducted to develop a model of energy expenditure in a population of white-tailed jackrabbits (Lepus townsendii). Field work in southwestern Wyoming during 1985-87 showed that the breeding season commenced at snowmelt and ceased during late- July drought. Adult females reproduced relatively synchronously and produced a mean of three litters annually. Greatest fetal production occurred in the second litter period. Collections indicated a 1:1 sex ratio, few jackrabbits >2 years-old, and a density of 7 animals / km2 in the population. Postnatal growth was sigmoidal, culminating in heavier adult females than males. Using …


Model Generation And Modification For Dynamic Systems From Geometric Data, Christoph M. Hoffmann, John E. Hopcroft Apr 1988

Model Generation And Modification For Dynamic Systems From Geometric Data, Christoph M. Hoffmann, John E. Hopcroft

Department of Computer Science Technical Reports

No abstract provided.


The Annual Meeting Of The Iowa Academy Of Science April 21-23, 1988 [Program, 100th Meeting], Iowa Academy Of Science Apr 1988

The Annual Meeting Of The Iowa Academy Of Science April 21-23, 1988 [Program, 100th Meeting], Iowa Academy Of Science

Iowa Academy of Science Documents

Program Contents:

Program Summary --- 5
General Session Speakers --- 9
Awards --- 13
Distinguished Fellows --- 13, 14
Distinguished Iowa Scientist --- 15
Distinguished Service --- 16
Symposia Programs --- 17
Video Film Preview --- 19
Special Meetings --- 20
Field Trip --- 20
Poster Papers --- 21
Campus Map --- Centerfold
Section Programs --- 25
Agricultural Sciences --- 26
Anthropology --- 28
Biotechnology --- 30
Botany --- 32
Chemistry, Inorganic --- 37
Chemistry, Organic --- 42
Conservation --- 44
Earth Science Teaching --- 46
Elementary Science Teaching --- 47
Engineering --- 48
Geology --- 53
Linguistics --- 58 …


Program Abstracts, 100th Session, Iowa Academy Of Science, April 21-23, 1988, Iowa Academy Of Science Apr 1988

Program Abstracts, 100th Session, Iowa Academy Of Science, April 21-23, 1988, Iowa Academy Of Science

Iowa Academy of Science Documents

Presentation abstracts from the annual meeting of the Iowa Academy of Science


Instream Flows, The Public Trust, And The Future Of The West, Harrison C. Dunning Apr 1988

Instream Flows, The Public Trust, And The Future Of The West, Harrison C. Dunning

Instream Flow Protection in the Western United States: A Practical Symposium (March 31-April 1)

65 pages (includes illustrations).

Contains 28 pages of footnotes.


The Probe, Issue 82 - April 1988 Apr 1988

The Probe, Issue 82 - April 1988

The Probe: Newsletter of the National Animal Damage Control Association

THE PROBE
National Animal Damage Control Association
APRIL 1988
Rodenticide Update
Overview of Anticoagulant Rodenticide Usage and Resistance
APHIS Activity Report
Childhood Antiques
“Non-Pesticide” Control
Wildlife Population Control
Letters to Ye Ed
California Vertebrate Pest Conference
101 Things To Do With an Incontinent Cat


Use Of 52Cr For The Quantitative Determination Of Red Cell Volume, Claude Michael Hanbury Apr 1988

Use Of 52Cr For The Quantitative Determination Of Red Cell Volume, Claude Michael Hanbury

Chemistry & Biochemistry Theses & Dissertations

Chromium-52 has recently been suggested for use as a new agent to label red cells for the in vivo quantitation of red cell volume (1). In this paper, the development and validation of a routine 52cr labeling procedure is described.

The accuracy, precision, and detection limits of chromium analysis by Zeeman effect atomic absorption spectroscopy was evaluated in the concentration range of 1 - 10 ug Cr/L.

Red cell chromium uptake was evaluated as a function of time, temperature, and concentration. Red cells labeled with a 2.5 mg/L chromium solution for 30 minutes at room temperature exhibited optimal label …


Reactions Of Aqueous Chlorine In The Gastric Fluid Of The Rat, Michael Gary Nickelsen Apr 1988

Reactions Of Aqueous Chlorine In The Gastric Fluid Of The Rat, Michael Gary Nickelsen

Chemistry & Biochemistry Theses & Dissertations

Gastric fluid was recovered from Sprague-Dawley rats that had been fasted for 24 hr or 48 hr and administered 4 mL deionized water. The protein, carbohydrate and chloride ion content of the gastric fluid was determined.

When gastric fluid is chlorinated with radiolabeled chlorine to concentrations between 323 and 375 mg/L, analyzed by high performance chromatography followed by liquid scintillation counting, as much as 59% of the radiolabeled chlorine was associated with organic components of the gastric fluid.

Model studies with the aromatic amino acids and the protein pepsin showed the formation of chlorinated analogs. Two chlorinated amino acid derivatives …


Closing Remarks For The Thirteenth Vertebrate Pest Conference, Lewis R. Davis Mar 1988

Closing Remarks For The Thirteenth Vertebrate Pest Conference, Lewis R. Davis

Vertebrate Pest Conference Proceedings: 13th (1988)

This brings to an end the Thirteenth Vertebrate Pest Conference. Without the speakers and the session chairs, there would not have been a conference. Let us acknowl¬edge them for the excellent job done.


Conference Participants: Thirteenth Vertebrate Pest Conference, Mar 1988

Conference Participants: Thirteenth Vertebrate Pest Conference,

Vertebrate Pest Conference Proceedings: 13th (1988)

The Conference totalled 401 registered attendees. The wide representation from the United States and from 14 countries throughout the world contributed to the success of the Conference by providing a highly diversified group for the exchange of ideas and information.


A Lexical Extension Of Montague Semantics, William C. Purdy Mar 1988

A Lexical Extension Of Montague Semantics, William C. Purdy

Electrical Engineering and Computer Science - Technical Reports

Montague's linguistic theory provides a completely formalized account of language in general and natural language in particular. It would appear to be especially applicable to the problem of natural language understanding by computer systems. However the theory does not deal with meaning at the lexical level. As a result, deduction in a system based on Montague semantics is severely restricted. This paper considers lexical extension of Montague semantics as a way to remove this restriction. Representation of lexical semantics by a logic program or semantic net is complex. An alternative representation, called a semantic space, is described. This alternative lacks …


The Probe, Issue 81 - March 1988 Mar 1988

The Probe, Issue 81 - March 1988

The Probe: Newsletter of the National Animal Damage Control Association

THE PROBE
National Animal Damage Control Association
MARCH 1988
Monterey Pest Conference
APHIS Activity Report
EPA – The Livestock Protective Collar
Frog Dissections
Letters to Ye Ed
The Endangered Species Act (ESA), EPA, ESO


Water Current, Volume 20, March 1988 Mar 1988

Water Current, Volume 20, March 1988

Water Current Newsletter

Changing World's Impacts on State's Water Issues Explored
Natural Resources Development in Depressed Areas Goals of CSD
Center to Search for Funds
Sheffield Receives Award
Nebraska's Available Water Supply "Same as Pioneer Days" - Dreeszen
Extension Water Group Broadens Base
Nebraska's Water Research Reviewed at "Update"
Nebraska Water Resources Center Projects for 1988
Health, Legal and Management Aspects of Water Examined


Frontmatter For Volume Of Proceedings Of The Thirteenth Vertebrate Pest Conference 1988, Mar 1988

Frontmatter For Volume Of Proceedings Of The Thirteenth Vertebrate Pest Conference 1988,

Vertebrate Pest Conference Proceedings: 13th (1988)

Frontmatter and Contents for the Thirteenth Vertebrate Pest Conference held at MONTEREY SHERATON HOTEL, Monterey, California, March 1,2 & 3, 1988.


The Pest Control Industry And The Challenges Ahead , Lee C. Truman Mar 1988

The Pest Control Industry And The Challenges Ahead , Lee C. Truman

Vertebrate Pest Conference Proceedings: 13th (1988)

The pest control industry, whether it be governmental, urban, aerial, lawn and turf, trees, or whatever, has many of the same problems. Controllers of vertebrate or invertebrate pests, or plant pests, have much in common. Environmental¬ists talk of the "balance of nature," usually overlooking the fact that nature is more often out of balance than in balance. Nature is cruel in its control of plant and animal species whenever there is not enough food to go around or enough of a suitable habitat in which to live. Nature does not conserve things as they are but, rather, changes them and …


Pesticides, Scientists, Farmers, And The Public: No "White Knight" Rescue In Sight, Pamela Jones Mar 1988

Pesticides, Scientists, Farmers, And The Public: No "White Knight" Rescue In Sight, Pamela Jones

Vertebrate Pest Conference Proceedings: 13th (1988)

ABSTRACT: The pesticide controversy is much more complicated than simply a disagreement over facts and risk estimates between the "experts" and the "fearful." It is a battle over ideology as much as one over information. This paper discusses the notion of "educating the public" about pesticides, establishing realistic expectations of efforts by industry and academia, and notes some of the limitations, and potential involvement, of scientists as "translators" in dealing with this controversy.


Animal Rights And Vertebrate Pest Control, Dale L. Brooks Mar 1988

Animal Rights And Vertebrate Pest Control, Dale L. Brooks

Vertebrate Pest Conference Proceedings: 13th (1988)

ABSTRACT: Many animal rights activists are very vocal in their belief that animals are more valuable or at least equally important to humans. There is little to no compromise in their overall view that the use of animals for food, fiber, teaching, research and testing does not result in improvements for other animals or societal needs. Today's activists are well prepared and very articulate in getting their views across to the public through the press and television media. An increasing number of the public is beginning to believe the activist allegations of inhumane animal practices. The biologist can no longer …