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Aspen Community Types Of Nevada, W. F. Mueggler Jan 1985

Aspen Community Types Of Nevada, W. F. Mueggler

Aspen Bibliography

No abstract provided.


A Macrofaunal Survey Of Three Contrasting Habitats Of The Littoral Zone In Cedar Lake, Illinois, Laura L. Holt Jan 1985

A Macrofaunal Survey Of Three Contrasting Habitats Of The Littoral Zone In Cedar Lake, Illinois, Laura L. Holt

Master's Theses

No abstract provided.


Introduction To Species Of Special Concern In Pennsylvania, Chapter 6--Mammals, Hugh H. Genoways Jan 1985

Introduction To Species Of Special Concern In Pennsylvania, Chapter 6--Mammals, Hugh H. Genoways

University of Nebraska State Museum: Mammalogy Papers

First two paragraphs:

The mammals in Pennsylvania have long been under the management authority of the Pennsylvania Game Commission, but it was not until 1978 that an effort was made to deal with threatened and endangered mammals in the Commonwealth. At this time, Michael J. Puglisi was appointed as Coordinator for the Threatened and Endangered Species Program within the Game Commission. In late February 1979, Mr. Puglisi asked Hugh H. Genoways to chair an informal study group on endangered mammals in Pennsylvania. The immediate concern of this group was to be the development of a list of threatened and endangered …


Evaluation Of Yield And Quality Of Cheddar Cheese Manufactured From Milk With Added Whey Protein Concentrate, Kirk Alan Baldwin Jan 1985

Evaluation Of Yield And Quality Of Cheddar Cheese Manufactured From Milk With Added Whey Protein Concentrate, Kirk Alan Baldwin

Electronic Theses and Dissertations

Large quantities of whey are produced as a by-product from the manufacture of cheese or casein. The United States has an annual cheese production of about 2.2 billion kg. The cheese industry has also experienced a steady increase in cheese production of about 6% a year (44). In the process, nearly 18.1 billion kg of whey are produced. Whey was once a discarded product of little value to the cheese producers. With the advent of laws and regulations governing the disposal of whey, whey became a problem that had few solutions. Even today, with the high cost of disposal and …


Identification Of Volatile Compounds Produced By Brevibacterium Linens That Inhibit Molds, Samuel E. Beattie Jan 1985

Identification Of Volatile Compounds Produced By Brevibacterium Linens That Inhibit Molds, Samuel E. Beattie

Electronic Theses and Dissertations

Mold contamination of processed food and its raw ingredients is a major concern in agriculture. Although at one time mold contamination of cheese and other foods was considered to be of little conse9uence, discovery of carcinogenic and/or teratogenic toxins (73) produced by molds commonly associated with food has changed this innocuous and frequent inconvenience into a serious health consideration. The presence of mold on or in cheese is a common occurrence, indeed, many cheeses depend upon molds to provide characteristic cheese flavor and texture. Cheeses such as blue, Roquefort, Camembert, and Brie are ripened under controlled conditions by species of …


Frontiers In Plant Science: Transcripts From A Symposium Sponsored By The Minnesota Academy Of Sciences, Gretchen Hagen, David D. Biesboer Jan 1985

Frontiers In Plant Science: Transcripts From A Symposium Sponsored By The Minnesota Academy Of Sciences, Gretchen Hagen, David D. Biesboer

Journal of the Minnesota Academy of Science

No abstract provided.


Distribution, Habitat, And Status Of The Gilt Darter (Percina Evides) In Minnesota, J. T. Hatch Jan 1985

Distribution, Habitat, And Status Of The Gilt Darter (Percina Evides) In Minnesota, J. T. Hatch

Journal of the Minnesota Academy of Science

The distribution and habitat of gilt darter (Percina evides) populations in Minnesota were studied from 1977 through 1983. Gilt darters occurred only in the St. Croix River drainage in moderate to large rivers or near the mouths of large streams. In the late spring, gilt darters were found most often in cobble raceways of moderate to swift current, where they later spawned. Young-of-the-year occupied this same habitat until early fall, when they and the adults moved to deep, swift chutes of rubble riffles to overwinter. Gilt darters tended to associate with the deeper, swifter portions of raceways and riffles, and …


The Biological Role Of Sialosyl Transferase Activity In Rat Brain, Robert Paul Durrie Jan 1985

The Biological Role Of Sialosyl Transferase Activity In Rat Brain, Robert Paul Durrie

Dissertations

No abstract provided.


The De Novo Biosynthesis Of Cytokinins By Cell-Free Extracts Of Baker's Yeast, Debra A. Tonetti Jan 1985

The De Novo Biosynthesis Of Cytokinins By Cell-Free Extracts Of Baker's Yeast, Debra A. Tonetti

Master's Theses

No abstract provided.


Seasonal-Changes In The Habitat Distribution Of Transient Insectivorous Birds In Southeastern Arizona: Competition Mediated, Richard L. Hutto Jan 1985

Seasonal-Changes In The Habitat Distribution Of Transient Insectivorous Birds In Southeastern Arizona: Competition Mediated, Richard L. Hutto

Biological Sciences Faculty Publications

The distribution and abundance of 26 migratory insectivorous bird species were recorded over an elevational habitat gradient in the Chiricahua Mountains, Arizona for the spring and fall migratory seasons. Most of the species used this area only during migratory passage, and 54% exhibited significant shifts in the habitats occupied from spring to fall. The majority (69%) of species also exhibited significant changes in density within habitats between seasons. Using pairwise correlations of bird densities from 7 habitat types and 2 seasons, I identified 5 groups that contained species whose seasonal distributional patterns were similar to one another but independent and …


A Survey Of Population Characteristics For Red Drum And Spotted Seatrout In Louisiana, John M. Wakeman, Paul R. Ramsey Jan 1985

A Survey Of Population Characteristics For Red Drum And Spotted Seatrout In Louisiana, John M. Wakeman, Paul R. Ramsey

Gulf and Caribbean Research

Red drum and spatted seatrout stocks were sampled from seven separate study areas along the Louisiana coast and from one estuarine area in Texas, with additional intensive temporal (monthly) and microgeographic (range of salinity regimes) samplings being carried out in one Louisiana study area. Condition coefficients, which did not appear to be affected by salinity regimes within the microgeographic sampling area, varied significantly according to study area, with Texas fish showing significantly lower condition coefficients than Louisiana fish. Van Bertalanffy growth equations were fitted and annual mortality rates were estimated to obtain preliminary estimates of yields, population numbers, and densities …


Metabolic Activity Of The Epiphytic Community Associated With Spartina Alterniflora, Wilmer C. Stowe, James G. Gosselink Jan 1985

Metabolic Activity Of The Epiphytic Community Associated With Spartina Alterniflora, Wilmer C. Stowe, James G. Gosselink

Gulf and Caribbean Research

Primary production and respiration rates were determined for two epiphytic communities associated with Spartina alternifloraLoisel., in the southwestern Barataria Bay area of Louisiana. The communities studied were: (1) a shoreline community and (2) a community 1.5 meters inland from the shoreline site. Annual mean net production and respiration rates for the shoreline community were 25.8 and -19.6 mg C • (m2 substrate area)-1 • h-1 respectively;whereas the inland community showed corresponding rates of -3.3 and -12.5 mg C • (m2 substrate area)-1 • h-1, respectively. Thus, the shoreline community was a net …


Spatial Influences On Temporal Variations In Leaf Growth And Chemical Composition Of Thalassia Testudinum Banks Ex König In Tampa Bay, Florida, Michael J. Durako, Mark D. Moffler Jan 1985

Spatial Influences On Temporal Variations In Leaf Growth And Chemical Composition Of Thalassia Testudinum Banks Ex König In Tampa Bay, Florida, Michael J. Durako, Mark D. Moffler

Gulf and Caribbean Research

The importance of spatial influences on seasonal fluctuations in Thalassia testudinum leaf blade lengths and chemical constituents was demonstrated. Differences between samples from fringe and mid-bed for several constituents were significant and, if not accounted for, could affect the measurement of apparent seasonal cycles. Fringe-shoots, reflecting the influence of more intense grazing activity, had shorter leaf blade lengths, lower dry weights and carbohydrate levels, and higher protein levels than mid-bed shoots. Mid-bed rhizomes and roots had highest protein and ash levels reflecting possible sediment influence. Percent ash and protein in the rhizomes, and percent carbohydrate in the roots exhibited seasonal …


Testis-Ova In Spawning Blue Tilapia, Oreochromis Aureus, B. Clark, H.J. Grier Jan 1985

Testis-Ova In Spawning Blue Tilapia, Oreochromis Aureus, B. Clark, H.J. Grier

Gulf and Caribbean Research

Hermaphroditism characterized by the presence of oocytes in the testes is described in the blue tilapia, Oreochromis aureus, for the first time. Testis-ova were observed in three of 24 spawning males exhibiting otherwise normal male morphology. The testis-ova appeared non-vitellogenic and lacked a follicle cell layer. It is speculated that the testis-ova did not become vitellogenic due to their association with Sertoli cells and the hormonal environment of the male.


Beating The Blackberry, J H. Moore, E. B. Hoskins Jan 1985

Beating The Blackberry, J H. Moore, E. B. Hoskins

Journal of the Department of Agriculture, Western Australia, Series 4

The blackberry is an aggressive, strongly-growing plant that has spread throughout parts of the south-west of Western Australia.

Although most blackberry infestations on agricultural land have been dramatically reduced since compulsory control measures were introduced 30 years ago, about 3,600 hectares are still infested today.

Recent research has shown that three new herbicides are highly effective against blackberry, and much safer to use than the older ones.

Effective biological control of blackberry may also be possible.


Seasonal Responses Of Filtration Rates To Temperature, Oxygen Availability, And Particle Concentration Of The Freshwater Clam, Musculium Partumeium (Say), Albert J. Burky, Richard B. Benjamin, Denis G. Conover, Jennifer Detrick Jan 1985

Seasonal Responses Of Filtration Rates To Temperature, Oxygen Availability, And Particle Concentration Of The Freshwater Clam, Musculium Partumeium (Say), Albert J. Burky, Richard B. Benjamin, Denis G. Conover, Jennifer Detrick

Biology Faculty Publications

Seasonal filtration rates of a pond population of the freshwater pisidiid clam, Musculium par­tumeium (Say), were assessed by measuring the clearance of 2.02 µ.m latex beads from suspension and expressed in terms of FR = a(AFDW}b where FR = filtration rate (ml H20 · hr- 1 ) , AFDW = mg ash-free dry weight of a whole clam and "a" and "b" are constants. The a-values ( = FR of a 1-mg AFDW clam} vary seasonally with the highest rates corresponding to periods of maximum growth and reproduction in the spring and fall. Changes in "b" reflect the influence of …


Effects Of Growth Temperatures On The Fatty Acid Composition Of Isolated Chloroplasts From Two Species Differing In Heat Sensitivity, Roy Z. Gehring, Glenn W. Todd Jan 1985

Effects Of Growth Temperatures On The Fatty Acid Composition Of Isolated Chloroplasts From Two Species Differing In Heat Sensitivity, Roy Z. Gehring, Glenn W. Todd

Journal of the Arkansas Academy of Science

Lipid analyses of chloroplasts isolated from wheat (Triticum aestivum L. cv. Arthur) and milo (Sorghum bicolor cv. Funk's hybrid 522) suggest no major heat effect on lipid class distribution. Assuming milo is more heat tolerant than wheat and that increased saturated/unsaturated fatty acid values increase thermal stability, changes in sulfoquinovosyldiglyceride (SL) appear to be more important than phosphatidylglycerol (PG) in conferring thermal stability to isolated chloroplasts.


Effects Of Gamma Radiation On Salix Nigra Marsh Cuttings, Roy Z. Gehring Jan 1985

Effects Of Gamma Radiation On Salix Nigra Marsh Cuttings, Roy Z. Gehring

Journal of the Arkansas Academy of Science

Dormant cuttings of Salix nigra Marsh, were exposed to gamma radiation from a cobalt-60 source at a dose rate of 1110 roentgens (r) per minute. Exposure doses ranged from 50 r through 100 Kr with 100% mortality at 10 Kr. Low doses of ionizing radiation apparently stimulated growth, while higher doses progressively retarded growth. The growth of the staminate catkins was inversely proportional to total exposure dose (increased dose resulted in progressively decreased growth). Determination of growth rates at different intervals post-irradiation indicated recovery of the surviving fraction of the irradiated cuttings. At ninety days, the highest growth rate occurred …


Compatibility Of Intercropping With Mechanized Agriculture: Effects Of Strip Intercropping Of Pinto Beans And Sweet Corn On Insect Abundance In Colorado, J. L. Capinera, Thomas J. Weissling, E. E. Schweizer Jan 1985

Compatibility Of Intercropping With Mechanized Agriculture: Effects Of Strip Intercropping Of Pinto Beans And Sweet Corn On Insect Abundance In Colorado, J. L. Capinera, Thomas J. Weissling, E. E. Schweizer

Department of Entomology: Faculty Publications

The potential for management of insect pest densities by regulation of crop diversity through intercropping was examined in sweet corn and pinto beans. Insect abundance was monitored in corn and beans in alternating multiple-row patterns of 1, 2, 4, 8, and 16 rows. Insect responses to intercropping treatments were variable, with positive, negative, and neutral responses observed, depending on species of insect and crop. In some cases, insect abundance was affected by strip-intercropping widths of up to eight rows, suggesting that strip intercropping may be compatible with some types of mechanized agriculture.


Soil Characteristics Of Four Juncus Roemerianus Populations In Mississippi, Lionel N. Eleuterius, John D. Caldwell Jan 1985

Soil Characteristics Of Four Juncus Roemerianus Populations In Mississippi, Lionel N. Eleuterius, John D. Caldwell

Gulf and Caribbean Research

The physical and chemical characteristics of soil from four widely separated Juncus roemerianus populations in Mississippi tidal marshes are determined. The J. roemerianus populations studied are located in Grand Bayou, Salt Flats, Weeks Bayou,and Belle Fantaine marshes. Organic matter, pH, CEC, N, P, K, Ca, S, Mg, and Zn analyses are based on composite soil samples. The percentage of sand, silt, and clay of the marsh soils is determined along with soil water content from the four locations. Statistical analysis indicates which marshes are different for each soil characteristic tested. No appreciable amounts of organic matter are present in the …


Breeding Biology Of The Great Crested Flycatcher, Myiarchus Crinitus, (Linnaeus) In Central Florida, Mark A. Kershner Jan 1985

Breeding Biology Of The Great Crested Flycatcher, Myiarchus Crinitus, (Linnaeus) In Central Florida, Mark A. Kershner

Retrospective Theses and Dissertations

No abstract provided.


Metatherian Reproduction: Transitional Or Transcending?, Virginia Hayssen, R. C. Lacy, P. J. Parker Jan 1985

Metatherian Reproduction: Transitional Or Transcending?, Virginia Hayssen, R. C. Lacy, P. J. Parker

Biological Sciences: Faculty Publications

The major difference between metatherian and eutherian reproductive patterns is the relative apportionment of maternal resources to gestation versus lactation, not the total temporal and energetic investment in each reproductive attempt. Gestation accounts for an average of 12% of the time from conception to weaning in marsupials; in placental mammals it accounts for 56% of this period of development. Parental investment at birth is less in marsupials (litter weight averages 0.09% of female body mass) than in eutherians (average 15.5%), but total maternal effort is comparable in the two groups, since the litter weight at weaning is similar for metatherians …


Isolation And Characterization Of The Crossreactive Antigenic And Allergenic Components In Callistemon Citrinis And Melaleuca Quinquenervia Pollen By Immunochemical Methods, Brett E. Stanaland Jan 1985

Isolation And Characterization Of The Crossreactive Antigenic And Allergenic Components In Callistemon Citrinis And Melaleuca Quinquenervia Pollen By Immunochemical Methods, Brett E. Stanaland

Retrospective Theses and Dissertations

No abstract provided.


Comparative Study Of Lactate Dehydrogenase Activity In Diving And Nondiving Reptiles, Dennis A. Baeyens, Deborah Bursey, Robert Rountree Jan 1985

Comparative Study Of Lactate Dehydrogenase Activity In Diving And Nondiving Reptiles, Dennis A. Baeyens, Deborah Bursey, Robert Rountree

Journal of the Arkansas Academy of Science

The properties of lactate dehydrogenase (LDH) were examined in two snake species and one turtle species. The snakes used in the study were the semi-aquatic Nerodia rhombifera and the terrestrial Elaphe obsoleta, while Pseudemys scripta represented the turtle species. Our purpose was to compare the LDH activity of nondiving reptiles (Nerodia and Elaphe) with that of the well established diver Pseudemys. The kinetic properties of LDH and its susceptibility to inhibition by elevated pyruvate concentrations were investigated in the brain and heart of the three species. Brain and heart were chosen because they are highly aerobic tissues and therefore should …


Effects Of Litter On Aquatic Macrophyte Germination And Growth, Mark F. Carter, Forrest E. Lane, James B. Grace Jan 1985

Effects Of Litter On Aquatic Macrophyte Germination And Growth, Mark F. Carter, Forrest E. Lane, James B. Grace

Journal of the Arkansas Academy of Science

In Arkansas, during seasonal drought periods, lake water levels drop leaving exposed mudflats which are primary sites for seedling establishment. Commonly, these exposed mudflats are partially covered with decomposing litter from previous stands of aquatic plants. In this study, aqueous leachates from the litter of four macrophytes, Eleocharis quadrangulata, Justicia americana, Polygonum lapathifolium, and Potamogeton nodosus, were used to test for chemical interference with germination and seedling growth. Only Justicia americana leachate was found to affect the growth of several of the test species. The potential for chemical interference by Justicia litter was evaluated further using extracts of acidified leachate. …


Repair Of Lethal Damage Induced In A Hamster X Amphibian Hybrid Tissue Culture Cell Line By Ultraviolet Light And Gamma Ray, Susan Kulp, Ann Page, H. Gaston Griggs Jan 1985

Repair Of Lethal Damage Induced In A Hamster X Amphibian Hybrid Tissue Culture Cell Line By Ultraviolet Light And Gamma Ray, Susan Kulp, Ann Page, H. Gaston Griggs

Journal of the Arkansas Academy of Science

A hybrid cell line was formed by fusing cells from two established vertebrate tissue culture cell lines (V79B1 hamster and A84 Xenopus), which were known to differ substantially in resistance to some radiation-induced lesions and in associated repair potential. Ultraviolet and gamma ray dose-survival relations were then determined and analyzed for the three cell lines, primarily to compare the radiosensitivity (Do dose) of the hybrid line with that of each parental line for each radiation. Further experimentation was conducted to determine the extent to which observed differences in these Do doses could be attributed to interactions of the combined parental …


Methemoglobin Reduction In The Presence Of Various Concentrations Of Oxyhemoglobin, Ali Mansouri Jan 1985

Methemoglobin Reduction In The Presence Of Various Concentrations Of Oxyhemoglobin, Ali Mansouri

Journal of the Arkansas Academy of Science

Methemoglobin reduction in human red blood cell is governed by many factors, one of which is the concentration of oxyhemoglobin. Experiments were conducted to determine the inhibition of methemoglobin reduction by oxyhemoglobin under concentrations approaching those in the red cell. Hemoglobin, methemoglobin reductase and cytochrome b₅ were prepared by routine protein purification methods. Methemoglobin reduction was carried out at 37° C in spectrophotometer. It is shown that methemoglobin concentration variation (at least when it is above 1 mM) does not change the reduction rate. Whereas, the ratio of methemoglobin to oxyhemoglobin determines the rate of methemoglobin reduction when all other …


Analysis Of Arkansas Fur Harvest Records - 1942-1984: I. State And Regional Accounts, Gary A. Heidt, James H. Peck, Tiny Sheldon, Joseph D. Clark Jan 1985

Analysis Of Arkansas Fur Harvest Records - 1942-1984: I. State And Regional Accounts, Gary A. Heidt, James H. Peck, Tiny Sheldon, Joseph D. Clark

Journal of the Arkansas Academy of Science

Fur harvest records maintained by the Arkansas Game and Fish Commission from 1942-1984 summarized the number of pelts sold by region (Ozark Mountains, Ouachita Mountains, Gulf Coastal Plain, and Mississippi Delta) and the average price per pelt for 16 furbearers. Analysis of these records showed that in the 1979-80 trapping season (the record year for both harvest and value both in Arkansas and the nation), the value of the Arkansas fur harvest ranked 14th nationally (2.12% of total national value). Fur harvests in Arkansas were high in the 1940's, declined in the 1950's and 1960's and then experienced a rapid …


Model To Predict Arkansas Gray Fox Fur Harvests, James H. Peck, Gary A. Heidt Jan 1985

Model To Predict Arkansas Gray Fox Fur Harvests, James H. Peck, Gary A. Heidt

Journal of the Arkansas Academy of Science

Linear regression analysis of total gray fox (Urocyon cinereoargenteus) fur harvests from 1954-1983 in Arkansas showed a high correlation with mean pelt values (r = 0.956). Single variable models using linear regression analyses of current season's pelt values (CSPV) and previous season's pelt values (PSPV) were designed to predict fur harvests. These models demonstrated high correlations for predicting harvests (r = 0.933 and r = 0.893 respectively). Regional analyses revealed a high correlation between mean pelt values and harvest for the Ozark Mountain region (r = 0.923), Ouachita Mountain region (r = 0.971 ), and Gulf Coastal Plain (r = …


Fluctuations And Relationships Of Selected Physiochemical Parameters In Dardanelle Reservoir, Arkansas, 1975-1982, John D. Rickett, Robert L. Watson Jan 1985

Fluctuations And Relationships Of Selected Physiochemical Parameters In Dardanelle Reservoir, Arkansas, 1975-1982, John D. Rickett, Robert L. Watson

Journal of the Arkansas Academy of Science

Annual and seasonal fluctuations and relationships are described for discharge, turbidity, chloride, total hardness, conductivity and suspended solids over an eight-year period in Dardanelle Reservoir. The parameters fluctuated rather widely primarily in response to seasonal patterns of rainfall. Chloride and conductivity were related and generally fluctuated together as did turbidity and suspended solids. Hardness appeared to vary independently of the others prior to 1979 then varied more closely with chloride after March 1979. Inherent differences between the Illinois Bayou arm and the main Arkansas River sections complicated the precise identification of any overall impact of power plant operation. No significant …