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Effect Of Nitrogen Levels On Metribuzin Tolerance In Tomatoes, Esther H. Nelson, Richard A. Ashley Nov 1980

Effect Of Nitrogen Levels On Metribuzin Tolerance In Tomatoes, Esther H. Nelson, Richard A. Ashley

Storrs Agricultural Experiment Station

No abstract provided.


Arrangement Of Subunits In Microtubules With 14 Profilaments, George M. Langford Nov 1980

Arrangement Of Subunits In Microtubules With 14 Profilaments, George M. Langford

Biology - All Scholarship

The structure of 14-protofilament microtubules reassembled from dogfish shark brain tubulin was analyzed by high resolution electron microscopy and optical diffraction. The simultaneous imaging of the protofilaments from near and far sides of these tubules produces a moiré pattern with a period of approximately 96 nm. Optical diffraction patterns show that the 5-nm spots that arise from the protofilaments for the two sides of the tubule are not coincident but lie off the equator by a distance of 1/192 nm-1. These data provide evidence that in reassembled microtubules containing 14 protofilaments, the protofilaments are tilted 1.5 degrees with respect to …


Beyond Conspecifics: Is Brer Rabbit Our Brother?, Gordon Burghardt, Harold Herzog Nov 1980

Beyond Conspecifics: Is Brer Rabbit Our Brother?, Gordon Burghardt, Harold Herzog

Experimentation Collection

Today, on many fronts, there is renewed interest in our relationship with nonhuman animals. Many factors have contributed to this concern. Environmental and ecological awareness has drawn public attention to the near extermination of many species and the detrimental effects of pollution, pesticides, and habitat destruction. The inefficiency of transmuting vegetable protein to meat has added to the traditional moral arguments of vegetarians. The widespread questioning of government support for basic research has been intertwined with suspicions about the use and worth of any studies on animals, even those purporting to help understand human medical and behavioral problems. New evidence …


Kentucky Warbler (Vol. 56, No. 4), Kentucky Library Research Collections Nov 1980

Kentucky Warbler (Vol. 56, No. 4), Kentucky Library Research Collections

The Kentucky Warbler

No abstract provided.


Alternative Male Life Histories In Bluegill Sunfish, Mart Gross, Eric Charnov Nov 1980

Alternative Male Life Histories In Bluegill Sunfish, Mart Gross, Eric Charnov

Biology Faculty & Staff Publications

Male bluegill sunfish are shown to have two alternative mating strategies: cuckoldry or parental care. Cuckolder males first mature at age 2. They follow a developmental sequence of sneaking and then mimicking female behavior to deceptively gain access to spawnings. Males who become parentals (construct nests, attract females, provide brood care) delay maturation until age 7. The parental investment of these males is parasitized by the cuckolders. This system is an example of a truly parasitically dependent mating strategy in vertebrates. A natural selection model is developed to predict the equilibrium frequencies of the two male types. A preliminary test …


Diversity And Dynamics Of Indigenous Rhizobium Japonicum Populations, K. Dale Noel, Winston J. Brill Nov 1980

Diversity And Dynamics Of Indigenous Rhizobium Japonicum Populations, K. Dale Noel, Winston J. Brill

Biological Sciences Faculty Research and Publications

A simple method, based upon the separation of cellular proteins by sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis, has been devised for distinguishing between isolates of Rhizobium japonicum. Eleven laboratory strains, previously classified into five serogroups, were analyzed by gel electrophoresis. Groups determined subjectively according to protein patterns matched the serogroups, with one exception. Most strains within serogroups could be distinguished from one another. For studying the ecology of Rhizobium, an important advantage of this technique compared with serology or phage typing is that it discriminates among previously unencountered indigenous bacterial isolates as well as among known laboratory strains. …


Geochemical And Biogeochemical Interactions In A Hot Spring, William Delis Knox Oct 1980

Geochemical And Biogeochemical Interactions In A Hot Spring, William Delis Knox

Dissertations and Theses

Southeast Harney Lake Hot Spring and its effluent channel were examined for spatial and temporal variations in the concentrations of several chemical species, viz. dissolved oxygen, pH, alkalinity, phosphate-phosphorous, nitrate and nitrite-nitrogen, conductivity, chloride, flouride, temperature, calcium, magnesium, potassium, and sodium. Phosphate-phosphorous and nitrate-nitrogen both exhibited downstream increases in concentration. pH and alkalinity increased also, mainly due to CO2 evolution and temperature mediated carbon species redistribution. The diurnal pH and alkalinity curves exhibited depressions during the daylight hours due to the oxidation of ammonia to nitrate within the pool and effluent stream.


South Dakota Farm And Home Research (Fall 1980), South Dakota State University Oct 1980

South Dakota Farm And Home Research (Fall 1980), South Dakota State University

South Dakota Farm and Home Research: 1949 -1998

This issue contains the 93rd South Dakota Agricultural Experiment Station Annual Report. This report covers July 1, 1979 - June 30, 1980.

Director’s Comments [p] 2
The Human Factor [p] 4
Beyond Our Borders [p] 6
Barleys Just for Us [p] 9
Bread and Butter [p] 13
Outreach [p] 15
A Day’s Work [p] 18
A Great Combination [p] 20
IPM [p] 23
93rd Annual Report [p] 25


Cultivating Killers: [Dr. William Trager], Fulvio Bardossi, Judith N. Schwartz Oct 1980

Cultivating Killers: [Dr. William Trager], Fulvio Bardossi, Judith N. Schwartz

Rockefeller University Research Profiles

Rockefeller University Research Profiles are a series of scientific profiles that were published quarterly, from 1980-1990, by the Rockefeller University. Each issue features the research and achievements of an individual Rockefeller University scientist.


Agricultural Experiment Station News October 1980 Oct 1980

Agricultural Experiment Station News October 1980

Agricultural Research Division: News and Annual Reports

CONTENTS:
FROM THE DIRECTOR'S DESK
GRANTS AND CONTRACTS
AGRICULTURAL EXPERIMENT STATION PUBLICATIONS - September 1980


Mineral Compostition Of Atriplex Hymenelytra Growing In The Northern Mojave Desert, A. Wallace, E. M. Romney, R. B. Hunter, J. E. Kinnear, G. V. Alexander Oct 1980

Mineral Compostition Of Atriplex Hymenelytra Growing In The Northern Mojave Desert, A. Wallace, E. M. Romney, R. B. Hunter, J. E. Kinnear, G. V. Alexander

Great Basin Naturalist Memoirs

Fifty samples of Atriplex hymenelytra (Torr.) S. Wats, were collected from several different locations in southern Nevada and California to test variability in mineral composition. Only Na, V, P. Ca, Mg, Mn, and Sr in the samples appeared to represent a uniform population resulting in normal curves for frequency distribution. Even so, about 40 percent of the variance for these elements was due to location. All elements differed enough with location so that no element really represented a uniform population. The coefficient of variation for most elements was over 40 percent and one was over 100 percent. The proportion of …


Parent Material Which Produces Saline Outcrops As A Factor In Differential Distribution Of Perennial Plants In The Northern Mojave Desert, A. Wallace, E. M. Romney, R. A. Wood, A. A. El-Ghonemy, S. A. Bamberg Oct 1980

Parent Material Which Produces Saline Outcrops As A Factor In Differential Distribution Of Perennial Plants In The Northern Mojave Desert, A. Wallace, E. M. Romney, R. A. Wood, A. A. El-Ghonemy, S. A. Bamberg

Great Basin Naturalist Memoirs

An area of 0.46 km2 divided into six zones in the northern Mojave Desert transitional with the Great Basin Desert has been studied. Diversity is high among the perennial plant species within the 0.46 km2 area. Common species for the two deserts that are present in the area studied are Atriplex confertifolia (Torr. & Frem.) S.Wats., Ceratoides lanata (Pursh) J. T. Howell, Grayia spinosa (Hook.) Moq., Ephedra nevadensis S. Wats. Some other species present include Lycium andersonii A. Gray, Lycium pallidum Miers, Ambrosia dumosa (A. Gray) Payne., Larrea tridentata (Sesse & Moc. ex DC) Cov., Acamptopappus shockleyi A. …


The Prairie Naturalist Volume 12, Numbers 3 And 4. September–December 1980 Oct 1980

The Prairie Naturalist Volume 12, Numbers 3 And 4. September–December 1980

The Prairie Naturalist

THE FLORA AND SANDHILLS PRAIRIE COMMUNITIES OF ARAPAHO PRAIRIE, ARTHUR COUNTY, NEBRASKA ▪ K. H. Keeler, A. T. Harrison and L. S. Vescio

USE OF ULTRASONIC SOUND TO ESTIMATE BODY FAT DEPOTS IN THE MALLARD ▪ G. A. Baldassarre, R. J. Whyte and E. G. Bolen

NORTHERN MOCKINGBIRD BREEDING IN NORTH DAKOTA ▪ D. Child, J. Fontaine, T. Gatz, M. Johnson and J. Oswald

SPRING ARRIVAL OF BIRDS AT WOODWORTH, NORTH DAKOTA ▪ K. F. Higgins, L. M. Kirsch, and J. M. Callow

HYBRIDIZATION AND TAXONOMIC STATUS OF GREATER PRAIRIE CHICKENS AND SHARP-TAILED GROUSE (HYBRIDIZATION IN GROUSE) ▪ D. W. …


Transpiration And Co2 Fixation Of Selected Desert Shrubs As Related To Soil-Water Potential, S. B. Clark, J. Letey Jr., O. R. Lunt, A. Wallace, G. E. Kleinkopf, E. M. Romney Oct 1980

Transpiration And Co2 Fixation Of Selected Desert Shrubs As Related To Soil-Water Potential, S. B. Clark, J. Letey Jr., O. R. Lunt, A. Wallace, G. E. Kleinkopf, E. M. Romney

Great Basin Naturalist Memoirs

In desert plants, transpiration rates decreased before photosynthetic rates when plants were entering a period of water stress. This may have adaptive consequences. A difference of -5 bars in the soil-moisture potential had considerable importance in reducing the rate of transpiration. In Helianthus annuus L. (sunflower) the photosynthetic rate decreased before the transpiration rate in contrast to Great Basin-Mojave Desert plants, and the changes occurred with a -1 bar difference in soil-moisture potential. Morphological changes in three desert plant species [Artemisia tridentata Nutt., Ambrosia dumosa (Gray) Payne, Larrea tridentata (Ses. Moc. ex DC) Cov.] as the soil-moisture potential decreased …


Zooplankton Abundance And Diversity In A Hydrilla Infested Central Florida Lake, Don C. Schmitz Oct 1980

Zooplankton Abundance And Diversity In A Hydrilla Infested Central Florida Lake, Don C. Schmitz

Retrospective Theses and Dissertations

Zooplankton abundance, hydrilla biomass, and physicochemical parameters were sampled for one year in a small central Florida lake. Annually, rotifers comprised most of the species collected and were the most abundant zooplankton group. Hydrilla biomass was lowest during winter and spring while orthophosphate and phtoplankton concentrations were highest. Zooplankton densities were highest when hydrilla biomass was low. Small-bodied limnetic herbivores comprised most of the zooplankton during the spring. Zooplanton abundances were lowest during summer and fall and may have been either directly or indirectly related to the hydrilla growth. Factors, such as lower phytoplankton and dissolved oxygen concentrations, possible increased …


Myxosoma Funduli Kudo 1918 (Protozoa: Myxosporida) In Fundulus Kansae (Pisces: Cyprinodontidae): Annual Prevalence And Geographic Distribution, Stephen A. Knight, John J. Janovy Jr., William L. Current Oct 1980

Myxosoma Funduli Kudo 1918 (Protozoa: Myxosporida) In Fundulus Kansae (Pisces: Cyprinodontidae): Annual Prevalence And Geographic Distribution, Stephen A. Knight, John J. Janovy Jr., William L. Current

John J. Janovy, Jr. Publications

The occurrence and distribution of the myxosporidan, Myxosoma funduli, in the Plains killifish (Fundulus kansae) were investigated. Samples from sites on the South Platte and Platte River drainages in Nebraska were collected by seining during various months of 1976, 1977, and 1978. At a number of the localities no F. kansae were found; the remainder of the collecting sites showed the host population to be abundant, but the M. funduli infections to vary in prevalence. The protozoan parasite population in F. kansae, upstream from the Nebraska Tri-County Diversion Dam and Canal, at North Platte, Nebraska, demonstrated …


An Evaluation Of Small Rodent Populations In Four Dismal Swamp Plant Communities, Fiona Elizabeth Breidling Oct 1980

An Evaluation Of Small Rodent Populations In Four Dismal Swamp Plant Communities, Fiona Elizabeth Breidling

Biological Sciences Theses & Dissertations

Diversity and density of small rodents in the Dismal Swamp are believed to be low. Reasons for this may be excessive predation, heavy interspecific pressure from larger rodents, lack of suitable habitat, low food availability or flooding.

Rodent populations were evaluated using live-traps and pitfall traps in four different Dismal Swamp plant communities. Habitat was compared on the basis of phytomass studies previously reported. Flood levels were recorded during live-trapping sessions. Mast from trees was collected in modified mast collectors, and fed to Peromyscus leucopus in the laboratory. Mast was analyzed for caloric value and nutrient content.

Only two …


The Synthesis And Biochemical Evaluation Of Potential Acetylcholinesterase Reactivators, Andrea Mcdearmid Lunsford Oct 1980

The Synthesis And Biochemical Evaluation Of Potential Acetylcholinesterase Reactivators, Andrea Mcdearmid Lunsford

Chemistry & Biochemistry Theses & Dissertations

Objectives of this research were to (1) synthesize, and (2) evaluate new compounds which would be potential reactivators of organophosphate-inhibited acetylcholinesterase.

A series of 1,8-diazafluorenone and 2,2'bipyridylketone oximes and oxime methiodides were synthesized (11, 13, 14, 22, 24). These compounds were developed as structural analogs of 2-PAM (2-Pyridinealdoxime methiodide) and TMB-4 (1,1Trimethylene-Bis(4-formylpyridinium bromide)dioxime), the current drugs of choice for treatment of organophosphorous poisoning.

Acetylcholinesterase from electric eel was inhibited with DFP (diisopropylfluorophosphate), an irreversible-type inhibitor, and the inhibited enzyme was treated with the various reactivator compounds. The reactivation assays were monitored with pH stat apparatus, and the data were evaluated …


Litter Production And Nutrient Content Of Litter In The Seasonally Flooded Dismal Swamp, Marta M. Gomez Oct 1980

Litter Production And Nutrient Content Of Litter In The Seasonally Flooded Dismal Swamp, Marta M. Gomez

Biological Sciences Theses & Dissertations

Litter production was studied in four plant communities in the Great Dismal Swamp, Virginia, that differ primarily in species composition and flooding regime. Greatest leaf deposition occurred in the more flooded communities, maple-gum (Acer-Nyssa) with 536 g m-2 yr-1 and cypress (Taxodium distichum (L.) Richard) with 528 g m-2 yr-1, followed by the cedar (Chamaecyparis thyoides (L.) BSP) and mixed hardwood (Quercus-Acer-Nyssa-Liquidambar) communities with 506 g m-2 yr-1 and 455 g m-2 yr-1, respectively. Litter nutrient concentrations were generally higher in the cypress and maple-gum stands, indicating greater nutrient availability …


Cytologic Characterization Of Human Constitutive Heterochromatin, Timothy Atchison Donlon Oct 1980

Cytologic Characterization Of Human Constitutive Heterochromatin, Timothy Atchison Donlon

Dissertations and Theses

A study was conducted to cytologically map certain subsets of constitutive heterochromatin onto specific portions of human chromosomes. This involved sequentially staining metaphase chromosomes from lymphocytes first with the Centromeric Dot, Giemsa-11, G-banding or Lateral Asymmetry staining techniques, which are cytochemical methods which stain particular chromosomes or chromosomal regions. Then those same metaphase chromosomes were stained using the C-banding technique, a method which is believed to denote constitutive heterochromatin. With the exception of the G-banding technique, areas depicted by the special staining techniques were found to reside only within the areas stained by the C-band technique and are thus believed …


Studies Of The Ichthyofauna Of Connecticut, Paul M. Jacobson Sep 1980

Studies Of The Ichthyofauna Of Connecticut, Paul M. Jacobson

Storrs Agricultural Experiment Station

No abstract provided.


The Psychological Relations Hip Between Dairy Cows And Dairy Cowmen And Its Implications For Animal Welfare, Martin F. Seabrook Sep 1980

The Psychological Relations Hip Between Dairy Cows And Dairy Cowmen And Its Implications For Animal Welfare, Martin F. Seabrook

International Journal for the Study of Animal Problems

No abstract provided.


The Effect Of Stress On Livestock And Meat Quality Prior To And During Slaughter, Temple Grandin Sep 1980

The Effect Of Stress On Livestock And Meat Quality Prior To And During Slaughter, Temple Grandin

International Journal for the Study of Animal Problems

The effects of stress on cattle, pigs and sheep prior to slaughter are reviewed. Long-term preslaughter stress, such as fighting, cold weather, fasting and transit, which occurs 12 to 48 hours prior to slaughter depletes muscle glycogen, resulting in meat which has a higher pH, darker color, and is drier. Short-term acute stress, such as excitement or fighting immediately prior to slaughter, produced lactic acid from the breakdown of glycogen. This results in meat which has a lower pH, lighter color, reduced water binding capacity, and is possibly tougher. Psychological stressors, such as excitement and fighting, will often have a …


Provisional Checklist Of Mammals Of South Dakota, Jerry R. Choate, J. Knox Jones Jr. Sep 1980

Provisional Checklist Of Mammals Of South Dakota, Jerry R. Choate, J. Knox Jones Jr.

University of Nebraska State Museum: Mammalogy Papers

Distributional patterns of mammals in South Dakota are among the most poorly known for any region of similar size in temperate North America. The only state-wide treatment of the group was the mimeographed compilation by Over and Churchill (1945), which consisted mostly of nontechnical anecdotes. Consequently, much of what is known of the distribution of South Dakotan mammals has been derived from localized inventories (Findley 1956a on Clay County ; Andersen and Jones 1971 on Harding County; Turner 1974 on the Black Hills; and Wilhelm et al. 1981 on Lacreek National Wildlife Refuge in Bennett County). These studies, supplemented with …


Agricultural Experiment Station News September 1980 Sep 1980

Agricultural Experiment Station News September 1980

Agricultural Research Division: News and Annual Reports

CONTENTS:
FROM THE DIRECTOR'S DESK
ACTIVITIES UPDATE
UPCOMING EVENTS
SAHS SEZ
GRANTS AND CONTRACTS
FOOD FOR THOUGHT


Mass Marking Of Mosquitofish: Preliminary Results, Bruce Vondracek, Wayne A. Wurtsbaugh, Joseph J. Cech Jr. Sep 1980

Mass Marking Of Mosquitofish: Preliminary Results, Bruce Vondracek, Wayne A. Wurtsbaugh, Joseph J. Cech Jr.

Watershed Sciences Faculty Publications

Three marking techniques were tested to determine their applicability for mosquitofish. Tetracycline drugs and DC Ar administered in the diet successfully marked laboratory-cultured mosquitofish, but exposure to direct sunlight in outdoor tanks resulted in the rapid disappearance of the marks. Preliminary data on fluorescent marks from a polystyrene pigment in a melamine-sulfonamide-formaldehyde resin forced into the dermal ,tissue with compressed air are more promising.

A t an optimal deliver pressure of 7.3 m Hg (140 p.s.i.) and spraying time of 15 sec., marking percentage is maximized and fish mortality is minimized. Mark retention time was up to 80 days in …


Effect Of Fish Size On Prey Size Selection In Gambusia Affinis, Wayne A. Wurtsbaugh, Joseph J. Cech Jr., James Compton Sep 1980

Effect Of Fish Size On Prey Size Selection In Gambusia Affinis, Wayne A. Wurtsbaugh, Joseph J. Cech Jr., James Compton

Watershed Sciences Faculty Publications

Food size selection of the mosquitofish , Gambusia affinis affinis. was measured in aquaria using juvenile stages of the mosquito, Clllex tarsalb;, as prey. Fish size varied from recently born fry to large adult females. Food size selection was positively correlated with fish size. Mosquitofish fry (6-8 111m standard length) attacked and ate primarily first and second instar larvae. Fry attacked larger instars, but attack success on these was low (0 - 50%). Fish larger than 20 mm attached primarily pupae and third and fourth instar larva. No first instar mosquitoes were eaten. Attack success for these fish was above …


Functions Of Deadenylation Factors In Mrna Decay And Mrna Processing Body Formation, Dinghai Zheng Sep 1980

Functions Of Deadenylation Factors In Mrna Decay And Mrna Processing Body Formation, Dinghai Zheng

Dissertations and Theses (Open Access)

Most newly synthesized messenger RNAs possess a 5’ cap and a 3’ poly(A) tail. The process of poly(A) tail shortening, also termed deadenylation, is important for post-transcriptional gene regulation, because deadenylation not only leads to mRNA translational inhibition but also is the first step of major mRNA degradation. Translationally inhibited mRNAs can be stored and/or degraded in dynamic cytoplasmic foci termed mRNA processing bodies, or P bodies, which are conserved in eukaryotes.

To shed new light on the mechanisms of P body formation and P body functions, I focused on the link between deadenylation factors and P bodies. I found …


The Effects Of Three Stretching Techniques On Flexibility, Mark Edward Wortman Sep 1980

The Effects Of Three Stretching Techniques On Flexibility, Mark Edward Wortman

Student Work

According to deVries (11), flexibility is defined as the range of possible movement in a joint or series of joints. The assessment of flexibility is a concern for both physical education and. the medical professions·. Apparently, an adequate amount of flexibility is essential for rehabilitation from injury,.prevention of injury and superior athletic performance (2, 8, 11, 14, 15, 16, 19, 21, 25, 31, 37, 43, 45). Presently, three stretching techniques are available: 1) static or slow sustained; 2) ballistic or bounce; 3) pro­-prioceptive neuromuscular facilitation (PNF). However, there appears to be no uniform agreement as to the best technique for …


The Flora And Sandhills Prairie Communities Of Arapaho Prairie, Arthur County, Nebraska, Kathleen H. Keeler, A. T. Harrison, L.S. Vescio Sep 1980

The Flora And Sandhills Prairie Communities Of Arapaho Prairie, Arthur County, Nebraska, Kathleen H. Keeler, A. T. Harrison, L.S. Vescio

School of Biological Sciences: Faculty Publications

The Arapaho Prairie is a 526-hectare (two-section) tract of upland Sandhills prairie located approximately nine miles southwest of the town of Arthur in Arthur Co., Nebraska (Sec. 31, 32 T18N R39W). The Prairie is at the extreme southwest edge of the 52,000-km2 Nebraska Sandhills (see Kaul 1975) and is floristically and ecologically typical of the slightly drier, western part of this vegetation type. Sandhills prairie which stretches across much of north central Nebraska is a unique type of "mixed" grassland (Pool 1914, Rydberg 1931, Tolstead 1942, Weaver 1965) created by impact of the dry, continental climate on the extensive …