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Field Notes, Jennifer K. Frey Jan 1989

Field Notes, Jennifer K. Frey

Division of Mammals - Field Notes and Catalogs

No abstract provided.


Rock Lobster Industry Advisory Committee Report To The Minister For Fisheries., Rock Lobster Industry Advisory Committee Jan 1989

Rock Lobster Industry Advisory Committee Report To The Minister For Fisheries., Rock Lobster Industry Advisory Committee

Fisheries Management Papers

The total catch of about 12.1 million kilograms for the 1987/88 season, based on processor returns, was an increase of 44% on the 1986/87 season. This very high catch, the third highest on record, resulted from an above average perulus settlement in 1983/84 and a "flow-on" of fast growing animals stemming from the expected high recruitment in 1988/990 caught as "reds" in 1987/88.

The Committee has identified five major elements related to the state of the rock lobster fishery upon which management advice is considered.

a) The undersize fraction of the population.

b) The "whites" which provide a significant proportion …


Specimen Catalog, Forrest W. Davis Jan 1989

Specimen Catalog, Forrest W. Davis

Division of Mammals - Field Notes and Catalogs

No abstract provided.


Field Notes, Forrest W. Davis Jan 1989

Field Notes, Forrest W. Davis

Division of Mammals - Field Notes and Catalogs

No abstract provided.


Specimen Catalog, Jennifer K. Frey Jan 1989

Specimen Catalog, Jennifer K. Frey

Division of Mammals - Field Notes and Catalogs

No abstract provided.


Genetics Of Intercellular Signalling In C. Elegans, Judith Austin, Eleanor M. Maine, Judith Kimble Jan 1989

Genetics Of Intercellular Signalling In C. Elegans, Judith Austin, Eleanor M. Maine, Judith Kimble

Biology - All Scholarship

Cell-cell interactions play a significant role in controlling cell fate during development of the nematode Caenorhabditis elegans. It has been found that two genes, glp-1 and lin-12, are required for many of these decisions. glp-1 is required for induction of mitotic proliferation in the germline by the somatic distal tip cell and for induction of the anterior pharynx early in embryogenesis. lin-12 is required for the interactions between cells of equivalent developmental potential, which allow them to take on different fates. Comparison of these two genes on a molecular level indicates that they are similar in sequence and organization, suggesting …


Expression Of Holo And Apo Forms Of Spinach Acyl Carrier Protein-I In Leaves Of Transgenic Tobacco Plants, M. A. Post-Beittenmiller, Katherine M. Schmid, J. B. Ohlrogge Jan 1989

Expression Of Holo And Apo Forms Of Spinach Acyl Carrier Protein-I In Leaves Of Transgenic Tobacco Plants, M. A. Post-Beittenmiller, Katherine M. Schmid, J. B. Ohlrogge

Scholarship and Professional Work - LAS

Acyl carrier protein (ACP) is a chloroplast-localized cofactor of fatty acid synthesis, desaturation, and acyl transfer. We have transformed tobacco with a chimeric gene consisting of the tobacco ribulose-1,5-bisphosphate carboxylase promoter and transit peptide and the sequence encoding the mature spinach ACP-I. Spinach ACP-I was expressed in the transformed plants at levels twofold to threefold higher than the endogenous tobacco ACPs as determined by protein immunoblots and assays of ACP in leaf extracts. In addition to these elevated levels of the holo form, there were high levels of apoACP-I, a form lacking the 4'-phosphopantetheine prosthetic group and not previously detected …


The Drosophila Female-Specific Sex-Determination Gene, Sex-Lethal, Has Stage-, Tissue-, And Sex-Specific Rnas Suggesting Multiple Modes Of Regulation, Helen K. Salz, Eleanor M. Maine, Linda N. Keyes, Mark E. Samuels, Thomas W. Cline, Paul Schedl Jan 1989

The Drosophila Female-Specific Sex-Determination Gene, Sex-Lethal, Has Stage-, Tissue-, And Sex-Specific Rnas Suggesting Multiple Modes Of Regulation, Helen K. Salz, Eleanor M. Maine, Linda N. Keyes, Mark E. Samuels, Thomas W. Cline, Paul Schedl

Biology - All Scholarship

For proper sexual development of females, the Sex-lethal (Sxl) gene must be activated early in development and remain on during the rest of the life cycle. Conversely, in males, Sxl must remain functionally off through development. Here, we show that the Sxl transcription unit spans a DNA segment of greater than 20 kb and encodes at least 10 distinct, but overlapping, RNA species. These RNAs range in size from 4.4 to 1.7 kb and exhibit sex, stage, and tissue specificity. Six RNAs, three female specific and three male specific, are first detected by midembryogenesis and persist through the adult stage: …


Trichome Development In Arabidopsis Thaliana. Ii. Lsolation And Complementation Of The Glabrous1 Gene, Patricia L. Herman, M. David Marks Jan 1989

Trichome Development In Arabidopsis Thaliana. Ii. Lsolation And Complementation Of The Glabrous1 Gene, Patricia L. Herman, M. David Marks

School of Biological Sciences: Faculty Publications

We are using the formation of trichomes in Arabidopsis thaliana as a model system to study gene expression during cellular differentiation. To initiate the molecular characterization of this system, we tagged and isolated a gene that is specifically required for the development of the specialized trichome cell. We confirmed the identity of this gene, GLABROUS1 (GL1), by complementation. These results demonstrate that a crucial gene in a plant developmental pathway can be successfully identified by complementation.


Characterization Of Chromosome Fragmentation In Two Protozoans And Identification Of A Candidate Fragmentation Sequence In Euplotes Crassus, Scott Everet Baird, Lawrence A. Klobutcher Jan 1989

Characterization Of Chromosome Fragmentation In Two Protozoans And Identification Of A Candidate Fragmentation Sequence In Euplotes Crassus, Scott Everet Baird, Lawrence A. Klobutcher

Biological Sciences Faculty Publications

Following the sexual cycle, hypotrichous ciliated protozoans fragment a set of their micronuclear chromosomes to generate the thousands of short, linear DNA molecules present in the transcriptionally active macronucleus. We have used a hybrid selection procedure to examine macronuclear DNA molecules for subtelomeric length heterogeneity to determine whether chromosome fragmentation occurs at unique or multiple sites. The results suggest that multiple, but closely spaced, chromosome fragmentation sites are used by Oxytricha nova. In contrast, Euplotes crassus uses unique chromosome fragmentation sites in a reproducible manner to generate the ends of macronuclear DNA molecules. Additional studies compared DNA sequences in …


A Field Study Using The Polymerase Chain Reaction (Pcr) To Screen For Brugia Microfilariae In Human And Animal Blood, Janet Glover, Steven A. Williams, Susanne Szabo, David Landry, Larry A. Mcreynolds, Taniawati Supali, Felix Partono Jan 1989

A Field Study Using The Polymerase Chain Reaction (Pcr) To Screen For Brugia Microfilariae In Human And Animal Blood, Janet Glover, Steven A. Williams, Susanne Szabo, David Landry, Larry A. Mcreynolds, Taniawati Supali, Felix Partono

Biological Sciences: Faculty Publications

Blood samples from 43 humans and 14 cats with Brugia microfilariae were analyzed in a field study in Tanjung Pinang, Indonesia. The study used the polymerase chain reaction (PCR) to compare the sensitivity of radioactive and biotinylated species-specific oligonuleotide probes. The cloning char- acterization of the Hha I repeat DNA family found in filarial parasites of the genus Brugia, and the development of species-specific probes for B.malayi and B.pahangi based on these repeats has been described elsewhere (PNAS USA 83: 797-801); Mol.Biochem. Parasitol. 28: 163-170). The use of radioisotopes for labelling DNA probes is both expensive and inconvenient. To replace …


Residual Influence Of Macronutrient Enrichment On The Aquatic Food Web Of An Okefenokee Swamp Abandoned Bird Rookery, J. Douglas Oliver, Steven A. Schoenberg Jan 1989

Residual Influence Of Macronutrient Enrichment On The Aquatic Food Web Of An Okefenokee Swamp Abandoned Bird Rookery, J. Douglas Oliver, Steven A. Schoenberg

Faculty Publications and Presentations

We present evidence for residual nutrient enrichment of diverse components of a blackwater marsh, by a biotic component of the ecosystem itself. Thousands of nesting white ibis (Eudocimus albus) that foraged over a 20-km radius fertilized a rookery with guano within Okefenokee Swamp. Georgia. USA. One to two yr after the birds abandoned it. this marsh showed continued enrichment effects. Elevated available phosphorus in sediments, as measured by equilibrium phosphate concentration, contributed to enhanced biomass of phytoplankton in the overlying water column. Planktivorous fish were greater in biomass than at reference sites. Experimental phosphorus and nitrogen fertilization of enclosures at …


Age And Growth Of King Mackerel, Scomberomorus Cavalla, From The Atlantic Coast Of The United States, Mark R. Collins, David J. Schmidt, C. Wayne Waltz, James L. Pinckney Jan 1989

Age And Growth Of King Mackerel, Scomberomorus Cavalla, From The Atlantic Coast Of The United States, Mark R. Collins, David J. Schmidt, C. Wayne Waltz, James L. Pinckney

Faculty Publications

Whole sagittae from 683 and sectioned sagittae from 773 "adult" (age> 0 ; 437-1.310 mm FL), and lapilli from 29 larval (2-7 mm SL) and 69 young-of-the-year (79-320 mm FL) king mackerel, were examined. All fish were from waters off the Atlantic coast of the southeastern United States (Cape Canaveral, Florida to Cape Fear. North Carolina). Back-calculated lengths at ages and von Bertalanffy growth equations were calculated from both whole and sectioned sagittae. Ages determined from sectioned sagittae were significantly greater than ages determined from whole sagittae, and the magnitude of the difference increased with age (from sections). Rings on …


Regulatory Cell Biology Of Growth Hormone And Prolactin In The Cow Mammary Gland, David Andrew Walkup Jan 1989

Regulatory Cell Biology Of Growth Hormone And Prolactin In The Cow Mammary Gland, David Andrew Walkup

Master's Theses

Prolactin (PRL) acts directly on milk secretory cell nuclei to stimulate lactation in rats. In the cow, PRL has been detected in Golgi apparatus, endoplasmic reticulum, and secretory vesicle subcellular fractions of mammary gland , but not nuclear fractions. However, growth hormone {GH) is the galactopoeitic hormone in cows, not PRL. The possibility of GH acting directly on the cow milk secretory cells, and PRL acting on their nuclei was investigated using an immunocytochemical method. PRL and GH were detected in endoplasmic reticular and Golgi apparatus regions of the milk secretory cells, as well as, on nuclear and fat globule …


Ontogenic Changes In The Rates Of Amino Acid Transport From Seawater By Marine Invertebrate Larvae (Echinodermata, Echiura, Mollusca), Donal T. Manahan, William Jaeckle, Saeid D. Nourizadeh Jan 1989

Ontogenic Changes In The Rates Of Amino Acid Transport From Seawater By Marine Invertebrate Larvae (Echinodermata, Echiura, Mollusca), Donal T. Manahan, William Jaeckle, Saeid D. Nourizadeh

Scholarship

Transport rates of amino acids were determined for larvae of different ages of the echiuran worm Urechis caupo, the gastropod Haliotis rufescens, the bivalve Crassostrea gigas, and the sea urchin Strongylocentrotus purpuratus. All larval forms showed an increase in the transport rate of amino acids during development. Trochophores of U. caupo increased their rate of net flux for each of 5 amino acids (100 nM each) by a factor of 1.6 and 2.2 during 1-3 days and 4-8 days, respectively, for two independent cultures. In H. rufescens, the maximum transport capacity (Jmax) …


Growth And Energy Imbalance During The Development Of A Lecithotrophic Molluscan Larva (Haliotis Rufescens), William Jaeckle, Donal T. Manahan Jan 1989

Growth And Energy Imbalance During The Development Of A Lecithotrophic Molluscan Larva (Haliotis Rufescens), William Jaeckle, Donal T. Manahan

Scholarship

Larvae of the gastropod Haliotis rufescens are classified as "nonfeeding" because they cannot capture particular foods. However, for only 1 out of 5 independent cultures was a net decrease observed in dry organic weight during the complete period of larval development (5 to 7 days). In fact, there were net increases in dry organic weight from the oocyte (day 0) to the newly formed veliger larvae (2-day-old). These weight increases during early development could be explained by increases in the amounts of specific biochemical components of the larvae, relative to oocytes. The metabolic rates of larvae were measured (oxygen consumption) …


Mercury In Fish From Northeastern Minnesota Lakes: Historical Trends, Environmental Correlates, And Potential Sources, Edward B. Swain, Daniel D. Helwig Jan 1989

Mercury In Fish From Northeastern Minnesota Lakes: Historical Trends, Environmental Correlates, And Potential Sources, Edward B. Swain, Daniel D. Helwig

Journal of the Minnesota Academy of Science

ABSTRACT-High mercury concentrations in fish of some Minnesota lakes and rivers were first noted in 1971. Major anthropogenic sources of mercury to Minnesota rivers generally have been identified and controlled, but it has been difficult to identify mercury sources to remote northeastern Minnesota lakes containing fish with elevated mercury levels. Analysis of sediments from these lakes suggests that mercury deposition has increased by a factor of about 3.5 since white settlement in the state. Because the increase is spatially constant across northeastern Minnesota, atmospheric pollution appears to be responsible for the increase. Given that fish mercury varies considerably among lakes, …


Phase-Variation Of Pyelonephritis-Associated Pili In Escherichia Coli: Evidence For Transcriptional Regulation, L. B. Blyn, B. A. Braaten, C. A. White-Ziegler, D. H. Rolfson, D. A. Low Jan 1989

Phase-Variation Of Pyelonephritis-Associated Pili In Escherichia Coli: Evidence For Transcriptional Regulation, L. B. Blyn, B. A. Braaten, C. A. White-Ziegler, D. H. Rolfson, D. A. Low

Biological Sciences: Faculty Publications

The regulation of pyelonephritis-associated pill (pap) pflin gene transcription has been examined using two operons (pap-17 and pap-21) isolated from the pyelonephritogenic Escherichia coli strain C1212. DNA sequence analysis and E.coli minicell analysis were used to map two genes (papB and papl) within the pilin regulatory regions of both pap-17 and pap-21, and the protein products of these genes were identified. Pilin transcription, initiated at the papBA promoter, was monitored by constructing single copy operon fusions with lacZYA in E.coli K-12. Inocula- tion of E.coli (pap'-lac) strains onto solid M9 minimal medium containing glycerol and the Lac indicator X-gal (M9-Glycerol) …


Tallgrass Prairie Remnants Of Eastern Nebraska, Judith F. Boettcher, Thomas B. Bragg Jan 1989

Tallgrass Prairie Remnants Of Eastern Nebraska, Judith F. Boettcher, Thomas B. Bragg

Biology Faculty Proceedings & Presentations

Ten eastern Nebraska tallgrass prairie remnants were evaluated up to four times during the 1979 growing season to assess vegetative composition and the effects of mowing, topographic and size differences, and season of evaluation. Frequent mowing resulted in a reduced canopy cover of some species, such as big bluestem (Andropogon gerardii Vitman) (21% lower with frequent mowing), but increased cover of others, particularly the introduced species smooth brome (Bromus inermis Leyss. subsp. inermis) (35% higher cover with frequent mowing). In addition, frequent mowing resulted in a higher proportion of disturbance species. Comparing the time of mowing, canopy …


Effect Of Eastern Red Cedar On Seedling Establishment Of Prairie Plants, Dan J. Stipe, Thomas B. Bragg Jan 1989

Effect Of Eastern Red Cedar On Seedling Establishment Of Prairie Plants, Dan J. Stipe, Thomas B. Bragg

Biology Faculty Proceedings & Presentations

To test the hypothesis that eastern red cedar (Juniperus virginiana L.) is allelopathic, seedling establishment of five herbaceous prairie species was evaluated by growing seeds in soil collected beneath and adjacent to a stand of this tree species. While four species showed no significant effect, the germination of one species, finger coreopsis (Coreopsis palmata Nutt.), was significantly reduced. Since eastern red cedar is an early invader of unburned prairie, such an allelopathic effect, even on only a few species, is of particular concern in that it has the potential to hasten degradation of invaded prairie sites.


Effect Of Burning On Germination Of Tallgrass Prairie Plant Species, Sherry R. Rohn, Thomas B. Bragg Jan 1989

Effect Of Burning On Germination Of Tallgrass Prairie Plant Species, Sherry R. Rohn, Thomas B. Bragg

Biology Faculty Proceedings & Presentations

Seeds from 10 prairie plant species of burned and unburned portions of three tallgrass prairies were collected and tested for germinability. Germination of big bluestem (Andropogon gerardii Vitman) consistently averaged higher with burning. Indiangrass (Sorghastrum nutans L.) and sideoats grama [Bouteloua curtipendula (Michx.) Torr.] averaged 5% higher with burning on two of the three sites, although for indiangrass average germination for all three sites was 7% lower. Species for which germination declined with burning were false sunflower [Heliopsis helianthoides (L.) Sweet var. scabra (Dun.) Fern.], -13%; whole leaf rosinweed (Silphium integrifolium Michx.), -10%; and white …


Establishing Warm-Season Grasses And Forbs Using Herbicides And Mowing, Thomas B. Bragg, David M. Sutherland Jan 1989

Establishing Warm-Season Grasses And Forbs Using Herbicides And Mowing, Thomas B. Bragg, David M. Sutherland

Biology Faculty Proceedings & Presentations

The objective of this study was to provide a preliminary assessment of the use of selected herbicides in establishing a diverse stand of prairie grasses and forbs. An upland and a lowland site in eastern Nebraska, consisting of well-drained, fine-silty clay, loess-derived soils, were seeded with 23 native prairie grass and forb species and subsequently mowed or treated at rates of 0.6, 1.1, 1.7, and 2.2 kg/ha with atrazine [6-chloro-Nethyl- N' -(l-methylethyl)-l ,3,S-triazine-2,4-diamine] or 2,4-0 (2,4-dichlorophenoxyacetic acid). Treatments were applied at one and two-year intervals. Canopy cover in unreplicated treatment areas (12 x 30 m) was evaluated in ten randomly …


An Annotated List Of The Vascular Plants Of Keith County, Nebraska, David M. Sutherland, Steven B. Rolfsmeier Jan 1989

An Annotated List Of The Vascular Plants Of Keith County, Nebraska, David M. Sutherland, Steven B. Rolfsmeier

Biology Faculty Publications

This study provides an annotated list of the vascular plants known to exist outside of cultivation in Keith County, Nebraska. Listed are a total of 599 species, subspecies and varieties belonging to 302 genera of 87 families. Notes are included about frequency and habitat for each of the taxa. 264 (44.1 %) of the taxa listed were previously unreported for Keith County. Additionally, the paper discusses vegetation regions in the county and gives information in tabular form about numbers of the flora in different taxa, the ten largest families, numbers of taxa of different growth habits, and numbers of taxa …


The Product Distribution And Structural Assignment Of The Monobromination Products Of 7-Hydroxy-2,2,5-Trimethylchroman-4-One, Rene Dutkowski Jan 1989

The Product Distribution And Structural Assignment Of The Monobromination Products Of 7-Hydroxy-2,2,5-Trimethylchroman-4-One, Rene Dutkowski

Dissertations and Theses @ UNI

Rearing conditions, such as temperature and humidity, may change behavior of Drosophila species so they behave differently than wild flies. The duration fruit flies are maintained in the laboratory prior to experimentation may cause genetic changes in the organism, due to selection, inbreeding, and drift. These genetic changes may lead to different responses to a temperature and humidity gradient by long-time laboratory reared stock and stock newly obtained from the wild. Past research revealed that Drosophila robusta and Drosophila tripunctata reared at 20ºC for five years in the laboratory preferred 20.0oC and 19.2oC respectively when they were allowed to move …


Use Of Solid-Phase Resins In Pesticide Monitoring, Jenny Bittinger Jan 1989

Use Of Solid-Phase Resins In Pesticide Monitoring, Jenny Bittinger

Honors Theses

The feasibility of using solid-phase resins for monitoring concentrations of pesticides in water was examined. Efforts were made to ascertain relationships between concentrations of a pesticide (methoxychlor) in water and on a resin (AXD-2) under laboratory conditions. Solutions of pesticide in water were drawn through columns of resin. Methylene Chloride was used to absorb the pesticide from the resin. Gas chromatography and ultraviolet spectrophotometry were used to measure concentrations of pesticide.


Community Responses To Variable Predation: Field Studies With Sunfish And Freshwater Macroinvertebrates, Mark J. Butler Iv Jan 1989

Community Responses To Variable Predation: Field Studies With Sunfish And Freshwater Macroinvertebrates, Mark J. Butler Iv

Biological Sciences Faculty Publications

The impact of variable predation by bluegill sunfish on macroinvertebrate prey in a North Florida lake is examined. Variable predation may occur in many systems and may contribute substantially to the spatial heterogeneity, temporal inconstancy and species composition of prey communities.

Patchy, temporally variable predation characterized middepth and deep lake habitats, whereas in the shallow zone predation was relatively constant and homogeneous. Predation varied significantly every 2-4 wk in the mid-depth zone, but varied little between consecutive weeks or days. Caging experiments revealed that variable predation altered prey community composition and increased the mean size and size range of some …


Amino Acids And N-Acetyl-Aspartyl-Glutamate As Neurotransmitter Candidates In The Monkey Retinogeniculate Pathways, Ricardo A. Molinar-Rode Jan 1989

Amino Acids And N-Acetyl-Aspartyl-Glutamate As Neurotransmitter Candidates In The Monkey Retinogeniculate Pathways, Ricardo A. Molinar-Rode

Dissertations, Theses, and Capstone Projects

The lateral geniculate nucleus (LGNd) receives chemically identified inputs from brain stem structures, the thalamus and visual cortex. The identity of the neurotransmitter(s) in the retinal input, however, is unknown.

To investigate the possibility that some amino acids and certain dipeptides, such as N-acetyl-aspartyl-glutamate (NAAG), fulfill this function, changes in their concentration were measured in the optic tract, parvocellular and magno-cellular segments of the LGNd, superior colliculus and visual cortex of six monkeys (Macaca fascicularis), seven days after right optic tractotomy. The LGNd was studied also in two additional macaques, three months after occipital lobectomy. Tissue was frozen within five …


Adaptive Variation In Environmental Sex Determination In A Nematode, Mark Blackmore, Eric Charnov Jan 1989

Adaptive Variation In Environmental Sex Determination In A Nematode, Mark Blackmore, Eric Charnov

Biology Faculty & Staff Publications

No abstract provided.


Phenotypic Evolution Under Fisher's Fundamental Theorem Of Natural Selection, Eric Charnov Jan 1989

Phenotypic Evolution Under Fisher's Fundamental Theorem Of Natural Selection, Eric Charnov

Biology Faculty & Staff Publications

I show the basic connection between the optimization and quantitative genetic approach to adaptation


Enigmatic Reptilian Sex Ratios, James Bull, Eric Charnov Jan 1989

Enigmatic Reptilian Sex Ratios, James Bull, Eric Charnov

Biology Faculty & Staff Publications

No abstract provided.