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A Classical Molecular Approach To Computer Simulation Of Biological Sorting, Donald Greenspan May 1980

A Classical Molecular Approach To Computer Simulation Of Biological Sorting, Donald Greenspan

Mathematics Technical Papers - Archive

Steinberg's theory of sorting is modified by replacing the free energy minimization principle with dynamical equations of a molecular nature. Correct cellular sorting then follows in all cases where the mixture is in a liquid or a near-liquid state. Computer examples are described and discussed, primarily for two dimensional, but also for three dimensional, interactions.


Stochastic Parameters In Compartmental Systems, Jerome Eisenfeld May 1980

Stochastic Parameters In Compartmental Systems, Jerome Eisenfeld

Mathematics Technical Papers - Archive

Let [see pdf for notation] denote the probability that a particle in compartment j will reach (or enter) compartment i. We present several formulas for obtaining the [see pdf for notation] in terms of the fractional transfer coefficients. The parameter are interesting for their own sake and they are also useful for obtaining qualitative properties of compartmental systems and for interpreting results already obtained. The reachability parameters also play a role in structural identification since they give us a new method for expressing the transfer function.


Water Current, Volume 12, No. 3, May/June 1980 May 1980

Water Current, Volume 12, No. 3, May/June 1980

Water Current Newsletter

From the Desk of the Director
Change of Address
Staff Members Resign
MRBC Adopts Regional Water Plan
Nebraska Game and Parks Commission
Mandatory Best Management Practices for New Federal Irrigation Projects in Nebraska
USGS FY 1981 Budget Request Cut $6.3 Million
WRC Completes Fiscal Year 1980 Grants to States
NSF Announces Anti-Inflation Budget for FY 1981
EPA Soliciation for Proposals


Effects Of Relaxation Therapy On Anxiety In Depressed Clients, Patricia Anne Worret May 1980

Effects Of Relaxation Therapy On Anxiety In Depressed Clients, Patricia Anne Worret

Loma Linda University Electronic Theses, Dissertations & Projects

During a psychiatric field placement, it was noted by this nurse researcher that patients with a diagnosis of depression often overtly displayed symptoms of anxiety. A brief literature review revealed that this anxiety-depression duality occurred frequently.

The purpose of this study was to determine if relaxation therapy was a therapeutic intervention which could be utilized by nurses to provide relief from the symptoms of the anxiety-depression syndrome. This was a clinical, quasi-experimental research investigation. The sample was chosen by a purposive, non-random selection of 20 experimental and 10 control subjects who were hospitalized with a diagnosis of depression in an …


A Study Of The Physiological And Mental Effects Of Various Shift Patterns On Registered Nurses, Carolyn Taylor Smith May 1980

A Study Of The Physiological And Mental Effects Of Various Shift Patterns On Registered Nurses, Carolyn Taylor Smith

Loma Linda University Electronic Theses, Dissertations & Projects

The effects of shift work on circadian I an rhythms has become a subject of great Interest to many industries, hospitals, and sleep researchers. More and more recognition is being given to the results of these studies, especially the possible adverse effects on those working the night shift or a shift they are unable to adapt to adequately. Only a few of these studies, however, have been conducted on registered nurses, a major group involved with shift work.

The purpose of the present study was to investigate the effects on nurses working the a.m. shift (7 a.m. to 3:30 p.m.), …


Chlorophyll Fluorescence Probe Of Ultraviolet-B Photoinhibition Of Primary Photoreactions In Intact Leaves, Robert S. Nowak May 1980

Chlorophyll Fluorescence Probe Of Ultraviolet-B Photoinhibition Of Primary Photoreactions In Intact Leaves, Robert S. Nowak

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Damage to primary photosynthetic reactions caused by environmental stress can be assessed by measurement of chlorophyll fluorescence induction in intact leaves. This approach was applied in studies of ultraviolet-B photoinhibition of photosynthesis in Pisum sativum L. and Rumex patientia L. leaves. At ultraviolet-B dose rates insufficient to cause inhibition of net photosynthesis, changes in the magnitude of fluorescence transients did occur, which suggested direct effects on chloroplast pigments in Pisum and inhibition of photosynthetic electron transport between the photosystems in both species. Leaves of these two species subjected to a much higher dose rate had a significant reduction of net …


Characteristics And Genesis Of Certain Soils In The Southern Foothills Of Central Alborz, Iran, Firouz Rooyani May 1980

Characteristics And Genesis Of Certain Soils In The Southern Foothills Of Central Alborz, Iran, Firouz Rooyani

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Characteristics and genesis of five pedons representing some of the soils of the central Alborz mountain northeast of Tehran were investigated. The present climate of the area is similar to the Mediterranean climate. The parent materials for the soils under study have apparently been derived from the Ecocene Alborz Green Beds (a thinly bedded light green mudstone), the Pliocene Hezardareh Formation (a poorly-cemented conglomerate) and Recent alluvium and colluvium. Pedons 2 and 4 are located at lower elevations (plain and river terraces) on 1 to 2 percent slopes. Pedons 3 and 5 are located at higher elevations (hills that surround …


Effects Of Host Plant Patch Size And Surrounding Plant Type On Insect Population Dynamics, Lynn A. Maguire May 1980

Effects Of Host Plant Patch Size And Surrounding Plant Type On Insect Population Dynamics, Lynn A. Maguire

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of the present study was to investigate how plant spatial patterns and insect behavior interact to influence the population dynamics of insects using the plants. The study included three phases: l) field experiments using collards (Brassica oleracea) and the crucifer insect fauna; 2) simulation models representing the population dynamics of an insect herbivore as functions of insect dispersal behavior and host plant patch size; and 3) model-field syntheses integrating model predictions and field variability estimates to choose an appropriate spatial scale for future field experiments or applications.

In field experiments on surrounding plant type, collards were …


Production Of Mountain Whitefish (Prosopium Williamsoni) In Altered And Unaltered Reaches Of Two Intermountain Streams In Their Alluvial Flood Plains, Michael J. Ottenbacher May 1980

Production Of Mountain Whitefish (Prosopium Williamsoni) In Altered And Unaltered Reaches Of Two Intermountain Streams In Their Alluvial Flood Plains, Michael J. Ottenbacher

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Estimates of production and related parameters (growth rate, density, standing crop) were made for populations of mountain whitefish in altered and "unaltered" areas of the Blacksmith Fork and Logan River, Utah from spring 1975 through summer 1976. Capture records of marked whitefish were also analyzed to describe fish movement and check on assumptions implicit in the population estimator.

Mean weights and instantaneous growth rates of whitefish were similar at all sites for comparable size/age groups. Among sites, differences in production per sampling interval and annual production were due mainly to differences in standing crop and/or age structure.

Estimates of mountain …


Resource Partitioning In Breeding Populations Of Marsh Hawks And Short-Eared Owls, Susan C. Linner May 1980

Resource Partitioning In Breeding Populations Of Marsh Hawks And Short-Eared Owls, Susan C. Linner

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

During the 1979 breeding season four pairs of northern harriers, or marsh hawks (Circus cyaneus) and four pairs of short-eared owls (Asio flammeus) were studied in Cache Valley, Utah. The study was concerned solely with diurnal resource utilization, and did not examine the owls' nocturnal activities. The home range of each harrier pair overlapped substantially with that of an owl pair. Percent habitat overlap for hawk-owl pairs varied from 39 percent to 72 percent. Observations were made to determine if differences existed in their utilization of habitat and food resources, or in their daily and seasonal …


Effects Of Pesticides On Immune Competency: Influence Of Methyl Parathion And Carbofuran On Immunologic Responses To Salmonella Typhimurium Infection, Anna M. Fan May 1980

Effects Of Pesticides On Immune Competency: Influence Of Methyl Parathion And Carbofuran On Immunologic Responses To Salmonella Typhimurium Infection, Anna M. Fan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Immunologic competence is correlated with resistance to infectious disease which may be affected by exposure to certain compounds. Methyl parathion (MP) and carbofuran (CF) have been reported to affect the development of active immunity in the rabbit and the present research was conducted to quantify the dosage relationships of these two pesticides to both host resistance and acquired resistance in the mouse.

Preliminary study was made on the virulence of Salmonella typhimurium in mice. Mortality rates among infected animals fed Purina Laboratory Chow diet providing 0.08, 0.7 3.0 mg MP/kg/day or 0.1, 0.6, 1.0 mg CF/kg/day along with untreated controls …


An Investigation Into A New England Fisheries Development Project: Towards The Expansion Of The Whiting Fishery, J. H. Kaelin Apr 1980

An Investigation Into A New England Fisheries Development Project: Towards The Expansion Of The Whiting Fishery, J. H. Kaelin

Marine Affairs Theses and Major Papers

In 1973, the New England Fishery Development Program (NEFDP), an industry/government partnership was formed to offset a portion of the economic decline of the New England fishing industry while encouraging the development of underutilized species and nontraditional fishery products. The purpose of this paper is to examine one of the NEFDP's development projects and to comment on its apparent success. This paper attempts to determine if domestic processors can be expected to produce whiting fillet blocks that can compete in the market place with foreign imports. Several aspects of the problem are favorably resolved-an abundant whiting resource is available; the …


Abstracts Of Papers, 92nd Session, Iowa Academy Of Science, April 18-19, 1980, Iowa Academy Of Science Apr 1980

Abstracts Of Papers, 92nd Session, Iowa Academy Of Science, April 18-19, 1980, Iowa Academy Of Science

Iowa Academy of Science Documents

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


The Annual Meeting Of The Iowa Academy Of Science April 18-19, 1980 [Program, 92nd Meeting], Iowa Academy Of Science Apr 1980

The Annual Meeting Of The Iowa Academy Of Science April 18-19, 1980 [Program, 92nd Meeting], Iowa Academy Of Science

Iowa Academy of Science Documents

No abstract provided.


Allocation Of Reproductive Effort To The Male And Female Strategies In Wind-Pollinated Plants, Cliff A. Lemen Apr 1980

Allocation Of Reproductive Effort To The Male And Female Strategies In Wind-Pollinated Plants, Cliff A. Lemen

School of Natural Resources: Faculty Publications

Amaranthus and several other wind-pollinated species of plants are used to test some of the theoretical models of relative reproductive effort towards the male and female sexes. Consistent with these models, in self-compatible, monoecious Amaranthus, Chenopodium, Digitaria, Setaria, and Lepidium, female effort represented over 90% of the total reproductive effort. Also consistent with predictions, Lolium, a self-incompatible wind-pollinated species, was found to have about equal male and female effort. A method is described here that should prove useful in quantifying male and female effort in both wind and insect-pollinated species of plants.


Intrapopulational Morphological Variation As A Predictor Of Feedlng Behavior In Deermice, Richard A. Smartt, Cliff A. Lemen Apr 1980

Intrapopulational Morphological Variation As A Predictor Of Feedlng Behavior In Deermice, Richard A. Smartt, Cliff A. Lemen

School of Natural Resources: Faculty Publications

Within populations of animals that have determinate growth, all fully grown adults, even of one sex, are not identical. Both genetic and environmental factors are responsible for this variation. In recent years the importance of this variation has received much attention (Mayr 1963; Van Valen 1965; Fretwell 1969; Soule and Stewart 1970; Rothstein 1973). The important question asked has been, What effect does this morphological variation have on niche width and the ecology of a population? Implicit in many of these works is the concept that differences in the morphologies of population members can result in differences in their niches. …


Relationship Between Relative Brain Size And Climbing Ability In Peromyscus, Cliff A. Lemen Apr 1980

Relationship Between Relative Brain Size And Climbing Ability In Peromyscus, Cliff A. Lemen

School of Natural Resources: Faculty Publications

Eisenberg and Wilson (Evolution, 32:740-751, 1978) have documented an interesting relationship between the relative brain size of bats and the complexity of the habitat in which they forage. They found that bats that fly and forage through foliage have larger brains relative to their body size than those that forage in open air. Their explanation was that bats in the complex habitat must process more complex sonic information to navigate through the foliage. In order to do this a larger brain is required.

The Peromyscus of North America may offer a similar paradigm as far as habitat complexity …


Ward V. Coleman, Cert. Granted (Sub Nom. United States V. Ward): A Fifth Amendment Problem In The Enforcement Of The Federal Water Pollution Control Act, Mark Cohen Apr 1980

Ward V. Coleman, Cert. Granted (Sub Nom. United States V. Ward): A Fifth Amendment Problem In The Enforcement Of The Federal Water Pollution Control Act, Mark Cohen

Marine Affairs Theses and Major Papers

On March 23, 1975 oil leaked out of an oil retention pit at a drilling site owned by L.O. Ward. Ward was an Oklahoma wildcatter and the owner and operator of L.O. Ward Oil and Gas Operations. The spilled oil ran down a gully and into Boggie Creek. Boggie Creek is a tributary of the navigable Arkansas River. The discharge of oil from Ward's property therefore amounted to the discharge of a harmful quantity of oil within the meaning of Section 1321 (b)(3) of the Federal Water Pollution Control Act and also a harmful quantity within the meaning of regulations …


Studies Of The Reorientational Relaxation Of Pyridine In Water By Depolarized Rayleigh Light Scattering, C. H. Wang, Scott L. Whittenburg, P. A. Lund, D. H. Christensen Apr 1980

Studies Of The Reorientational Relaxation Of Pyridine In Water By Depolarized Rayleigh Light Scattering, C. H. Wang, Scott L. Whittenburg, P. A. Lund, D. H. Christensen

Chemistry and Biochemistry Faculty Publications

The depolarized Rayleigh spectra of aqueous solutions of pyridine have been studied using a high‐finesse Fabry–Perot interferometer as a function of temperature and concentration. The Rayleigh relaxation times are found to have a complex concentration and viscosity dependence. The classical Stokes–Einstein–Debye equation for molecular reorientation breaks down in this system. The Rayleigh relaxation time of pyridine molecules is not determined by the macroscopic shear viscosity of the solution. The specific interaction due to the formation of hydrogen bonds between pyridine and water molecules plays a very important role in affecting the relaxation time. At a fixed temperature the plot of …


An Avoidance Response Bioassay For Aquatic Pollutants, Jeffrey A. Black, Wesley J. Birge Apr 1980

An Avoidance Response Bioassay For Aquatic Pollutants, Jeffrey A. Black, Wesley J. Birge

KWRRI Research Reports

Avoidance response bioassays were conducted with eight aquatic contaminants, including cadmium, copper, mercury, zinc, chloroform, dioctyl phthalate (DOP), trisodium nitrilotriacetic acid (NTA), and phenol. Tests were performed in a dual-channel fluviarium system, and the toxicant injection procedure used provided good regulation of exposure concentrations. Juvenile stages of largemouth bass (Micropterus salmoides), bluegill sunfish (Lepomis macrochirus), and rainbow trout (Salmo gairdneri), and tadpoles of the American toad (Bufo americanus) proved to be suitable animals for evaluating avoidance or attraction responses. The trout was the most sensitive species tested.

Avoidance was significant in tests …


Distribution Of The Dinoflagellate Symbiosis In Astragia Danae As Affected By Light Attenuation, Michael Perry Weston Apr 1980

Distribution Of The Dinoflagellate Symbiosis In Astragia Danae As Affected By Light Attenuation, Michael Perry Weston

OES Theses and Dissertations

Spatial zonation of symbiotic and aposymbiotic forms of the temperate coral Astrangia danae provides evidence that light attenuation is an important factor in the distribution of this animal. At four locations in the lower Chesapeake Bay and adjacent offshore waters, symbiotic colonies were observed only in well illuminated surface waters, while aposymbiotic colonies were observed in less illuminated deeper waters. A transition zone exists in which both colony types are found. Colonies on substrates forming a plane parallel to the sea-surface receive a greater radiant flux than colonies on vertical substrates. This extends the depth range of symbiotic colonies located …


Isolation And Enumeration Of Enteric Viruses From Primary Wastewater Sludge, Michael Wayne Nath Apr 1980

Isolation And Enumeration Of Enteric Viruses From Primary Wastewater Sludge, Michael Wayne Nath

Biological Sciences Theses & Dissertations

The presence of large numbers of enteric viruses in wastewaters has resulted in concern regarding their significance and consequences for humans. Assessments of relative significance or consequences may most accurately be made following precise measurements of the range of virus types and amounts in wastewaters and sludges and after epidemiological considerations. In this study, results are presented pertaining to enteric virus isolation, concentration, and enumeration from primary wastewater sludges.

As an integral part of a comparison of isolation procedures, several anionic surfactants were examined for extraction of enteric viruses from primary wastewater sludges. Plaquing efficiencies for poliovirus type 2 and …


Macrobenthic Communities Of An Industrialized Seaport Ecosystem: The Southern Branch Of The Elizabeth River, Virginia, Steven D. Hawthorne Apr 1980

Macrobenthic Communities Of An Industrialized Seaport Ecosystem: The Southern Branch Of The Elizabeth River, Virginia, Steven D. Hawthorne

Biological Sciences Theses & Dissertations

Macrobenthic invertebrates of an industrialized seaport ecosystem were studied seasonally from October, 1977 through July, 1978. Five stations were selected along the Southern Branch of the Elizabeth River, Virginia. The stations ranged from an area of heavy industrialization to a non-urbanized environment. At each station, bottom water was measured for salinity, temperature, dissolved oxygen, and pH. Within each sampling area, macrobenthic infauna! invertebrates were collected from in and out of channel sites along with sediment samples for various types of physicochemical analysis.

Community structure was spatially homogeneous at station sites and throughout the stations along the River. Slightly acidic pH …


Filtration Ingestion And Assimilation Rates Of The Mysid Shrimp Neomysis Americana Smith, Fed Three Food Sources, Robert W. Grabb Apr 1980

Filtration Ingestion And Assimilation Rates Of The Mysid Shrimp Neomysis Americana Smith, Fed Three Food Sources, Robert W. Grabb

OES Theses and Dissertations

Laboratory grazing and assimilation experiments were conducted on the mysid shrimp Neomysis americana in an attempt to assess the suitability of three potential food sources. It was hypothesized that the smaller size classes were primarily herbivores, not becoming omnivorous until attaining lengths of approximately 5-6 mm. Four size classes of mysids from the summer generation, juveniles, immature, adult males, and adult ovigerous females were each fed three concentrations of Artemia salina nauplii, the rotifer Brachionus plicatilis, and the diatom Coscinodiscus lineatus. The mean lengths of the size classes utilized, plus or minus one standard deviation, were 2.5 …


Mountain Beaver Problems In The Forests Of California, Oregon And Washington, John E. Borrecco, Robert J. Anderson Mar 1980

Mountain Beaver Problems In The Forests Of California, Oregon And Washington, John E. Borrecco, Robert J. Anderson

Vertebrate Pest Conference Proceedings: 9th (1980)

Mountain beavers (Aplodontia rufa) cause considerable damage to forest trees in the Pacific Northwest. Feeding injuries result in mortality, growth losses, deformity of trees, and understocked plantations. Losses are most severe in new plantations with significant damage problems also occurring in sapling stands. Trapping, and placing physical barriers around individual trees, are the most common methods of control. Both methods are costly but effective in reducing damage.


The Situation Of Grain-Eating Birds In Somalia, Richard L. Bruggers Mar 1980

The Situation Of Grain-Eating Birds In Somalia, Richard L. Bruggers

Vertebrate Pest Conference Proceedings: 9th (1980)

Research into the biology and control of pest birds in Somalia has continued intermittently since 1971 under UNDP funding of four projects. Data have been gathered on the identification, distribution, and status of the principal pest species to agriculture. These species include the Red-billed Quelea (Quelea quelea), of which northern and southern races occur, and several other ploceid weavers (Ploceus spp.) which may damage cereal crops. The movements, food habits, and corresponding impact of these species on agriculture in Somalia are discussed in detail. As a result of the information obtained during these years of research, emphasis has recently shifted …


Armadillos: Problems And Control, Patricia A. Chamberlain Mar 1980

Armadillos: Problems And Control, Patricia A. Chamberlain

Vertebrate Pest Conference Proceedings: 9th (1980)

The nine-banded armadillo (Dasypus novemcinctus) has been successful in extending its range throughout the southeastern states. It occupies such a diverse range of habitats that its effects on its surroundings depend largely on where it is located. It offers benefits from its burrowing and eating patterns by creating dens for furbearers and destroying large quantities of injurious insects and their larva. Those same activities in urban and suburban areas are now being recognized as a source of considerable nuisance and moderate damage. Damage is most severe from July through early November. They have been recognized in connection with several diseases …


Proceedings: Ninth Vertebrate Pest Conference Mar 1980

Proceedings: Ninth Vertebrate Pest Conference

Vertebrate Pest Conference Proceedings: 9th (1980)

Proceedings: Ninth Vertebrate Pest Conference


Socioeconomic And Ecological Aspects Of Field Rat Control In Tropical And Subtropical Countries, Hans Kurylas Mar 1980

Socioeconomic And Ecological Aspects Of Field Rat Control In Tropical And Subtropical Countries, Hans Kurylas

Vertebrate Pest Conference Proceedings: 9th (1980)

The vital question, as to the cause of the permanent increase in field rat populations throughout most tropical and subtropical areas, has been the subject of researchers and fieldmen during the past years, in the hope of finding an answer to this problem. Man has made his way through history wherein he was gradually able to renounce nature and establish his own man-made cultural frame. Unlike other mammals, man has no natural instincts to guide him through life. Brain and spirit have to compensate for lack of physical capabilities and instincts. Man was forced to change his natural surroundings in …


Closing Remarks ─ Ninth Vertebrate Pest Conference , Rex E. Marsh Mar 1980

Closing Remarks ─ Ninth Vertebrate Pest Conference , Rex E. Marsh

Vertebrate Pest Conference Proceedings: 9th (1980)

Closing Remarks