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Articles 148471 - 148500 of 158662

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Wood Utilization In Aspen: Ecology And Management In The Western United States, E.M. Wengert, D.M. Donelly, D.C. Markstrom, H.E. Worth Jan 1985

Wood Utilization In Aspen: Ecology And Management In The Western United States, E.M. Wengert, D.M. Donelly, D.C. Markstrom, H.E. Worth

Aspen Bibliography

In the past, markets for quaking aspen timber from the Rocky Mountains have been insufficient to support significant harvesting. This shortage of markets severely restrained the potential for aspen management. As a result, many stands protected from wildfire gradually reverted to conifers (see the VEGETATIVE REGENERATION and FIRE chapters).


Vegetative Regeneration In Aspen: Ecology And Management In The Western United States, George A. Schier, John R. Jones, Robert P. Winokur Jan 1985

Vegetative Regeneration In Aspen: Ecology And Management In The Western United States, George A. Schier, John R. Jones, Robert P. Winokur

Aspen Bibliography

No abstract provided.


Forage In Aspen: Ecology And Management In The Western United States, Walter F. Mueggler Jan 1985

Forage In Aspen: Ecology And Management In The Western United States, Walter F. Mueggler

Aspen Bibliography

No abstract provided.


Insects And Other Invertebrates In Aspen: Ecology And Management In The Western United States, J.R. Jones, N.V. Debyle, D.M. Bowers Jan 1985

Insects And Other Invertebrates In Aspen: Ecology And Management In The Western United States, J.R. Jones, N.V. Debyle, D.M. Bowers

Aspen Bibliography

No abstract provided.


Wildlife In Aspen: Ecology And Management In The Western United States, Norbert V. Debyle Jan 1985

Wildlife In Aspen: Ecology And Management In The Western United States, Norbert V. Debyle

Aspen Bibliography

Aspen forests provide important habitat for many species of wildlife (Gullion 1977b), especially in the West (see the appendix to this chapter). In the coniferous forests of the interior West, aspen groves may be the only source of abundant forage; in the grasslands they may be the sole source of cover. A primary value of the aspen ecosystem in the West during the past century has been production of forage for both wildlife and domestic livestock (see the FORAGE chapter).


Guidelines For Managing Aspen, The Aspen Panel Jan 1985

Guidelines For Managing Aspen, The Aspen Panel

Aspen Bibliography

No abstract provided.


On Irreversible Evolution, James Bull, Eric Charnov Jan 1985

On Irreversible Evolution, James Bull, Eric Charnov

Biology Faculty & Staff Publications

No abstract provided.


Yield-Per-Recruit Of Spotted Seatrout, Richard E. Condrey, Gerald Adkins, Michael W. Wascom Jan 1985

Yield-Per-Recruit Of Spotted Seatrout, Richard E. Condrey, Gerald Adkins, Michael W. Wascom

Gulf and Caribbean Research

A von Bertalanffy growth curve,

L = 65.47 cm (1 - e-.2005 (t + .4113 yr)),

is derived from published data on spotted seatrout in the U.S. Gulf of Mexico and used in constructing a yield-per-recruit contour. Maximum yield-per-recruit is approached as F increases above 1 and age of first entry approaches 3.9 years (14.9 in., 1.1 lb). A linear regression is derived relating average size of capture to gill net mesh size (MS in inches),

L = 1.97 in. + 8.63 MS,

and used along with legal sizes of first harvest to evaluate the impact of current …


Effect Of Dietary Fat On Pig Performance And Dust Levels In Modified-Open-Front And Environmentally Regulated Confinement Buildings, L. I. Chiba, E. R. Peo, Jr., A. J. Lewis, M. C. Brumm, R. D. Fritschen, J. D. Crenshaw Jan 1985

Effect Of Dietary Fat On Pig Performance And Dust Levels In Modified-Open-Front And Environmentally Regulated Confinement Buildings, L. I. Chiba, E. R. Peo, Jr., A. J. Lewis, M. C. Brumm, R. D. Fritschen, J. D. Crenshaw

Department of Animal Science: Faculty Publications

Four trials were conducted with 1,480 pigs (initial wt: 23 kg in trial 1, 29 kg in trial 2 and 49 kg in trial 3 and 4) to determine the effect of dietary fat on pig performance, nutrient separation in an automated feed distribution system, dust levels in swine buildings and integrity of the respiratory system of swine. Two modified-open-front (B-1 and B-2) and two environmentally regulated (E-1 and E-2) growing-finishing buildings, of identical design, were used in each trial. In trial 1,250 pigs (25 pens of 10 pigs/pen) in B-1 were fed a ground, mixed, corn-soybean meal diet (15% …


An Evaluation Of Threonine And Isoleucine As The Third And Fourth Limiting Amino Acids In Corn For Growing Swine, D. A. Grosbach, A. J. Lewis, E. R. Peo, Jr. Jan 1985

An Evaluation Of Threonine And Isoleucine As The Third And Fourth Limiting Amino Acids In Corn For Growing Swine, D. A. Grosbach, A. J. Lewis, E. R. Peo, Jr.

Department of Animal Science: Faculty Publications

A metabolism experiment and two growth experiments were conducted to determine if threonine and isoleucine are the third and fourth limiting amino acids in corn for growing swine. In each experiment there were four dietary treatments. The basal diet contained corn fortified with minerals, vitamins, lysine and tryptophan. Threonine additions of 0 or .17% and isoleucine additions of 0 or .22% of the diet were evaluated in a 2 • 2 factorial arrangement of treatments. The addition of threonine reduced (P<.001) the daily urinary excretion of urea N and total N. There was a tendency for urea N excretion to be reduced further when isoleucine was added in combination with threonine.


Heterogenity Of The Spawning Populations Of Surf Smelt In The State Of Washington, Raj V. Kilambi Jan 1985

Heterogenity Of The Spawning Populations Of Surf Smelt In The State Of Washington, Raj V. Kilambi

Journal of the Arkansas Academy of Science

Biometric comparisons of three spawning populations of surf smelt, one from Pacific Coast and two from Puget Sound, were made. The Puget Sound populations (Hood Canal and Utsaladdy) were more similar to each other compared to the ocean populations. The Hood Canal and Utsaladdy smelt exhibited least distance function, D^2 , and greater overlap of meristic characters compared to the Lapush fish. It was postulated that the Puget Sound smelt populations were derived from the ocean smelt some 13,000 or more years ago.


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

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

Journal of the Arkansas Academy of Science

Fur harvest records were maintained by the Arkansas Game and Fish Commission on the following 16 furbearers: badger, beaver, bobcat, eastern spotted skunk (civet), coyote, gray fox, long-tailed weasel, mink, muskrat, nutria, opossum, raccoon, red fox, red wolf, river otter, and striped skunk. These harvest records were analyzed for each species in terms of mean pelt price and numbers of pelt sold by region (Ozark Mountains, Ouachita Mountains, Gulf Coastal Plain, and Mississippi Delta) per year. Historical or biological influences important in interpreting species accounts are presented.


Changes In Forest Soils Following Clearcutting Of Pine Forests In The Ouachita Mountains Of Arkansas, Harlan R. Stoin, Bajuri Bin Kadmin, Lyell F. Thompson Jan 1985

Changes In Forest Soils Following Clearcutting Of Pine Forests In The Ouachita Mountains Of Arkansas, Harlan R. Stoin, Bajuri Bin Kadmin, Lyell F. Thompson

Journal of the Arkansas Academy of Science

Soil characteristics of the mineral surface soil (0-6 cm) on three small watersheds in the Ouachita Mountains of Arkansas from which the pine forests have been clearcut, crushed, and burned for site preparation were studied for the first two years following clearcutting and compared to soils from adjacent uncut pine forest watersheds. Following clearcutting and burning, soil pH was generally higher than in uncut forest soils. The greatest pH differences occurred within several months of burning and generally decreased through the end of the second year. Soil organic matter content was lower immediately following clearcutting and burning and increased to …


Fall Deer Food Selection In The Ouachita National Forest, James D. Fenwood, David A. Saugey, Carl A. Racchini Jan 1985

Fall Deer Food Selection In The Ouachita National Forest, James D. Fenwood, David A. Saugey, Carl A. Racchini

Journal of the Arkansas Academy of Science

No abstract provided.


Synopsis Of The Hydrometridae Of Arkansas, George L. Harp Jan 1985

Synopsis Of The Hydrometridae Of Arkansas, George L. Harp

Journal of the Arkansas Academy of Science

No abstract provided.


Distribution And Status Of Etheostoma Cragini Gilbert And E. Microperca Jordan And Gilbert In Arkansas, John L. Harris, Kenneth L. Smith Jan 1985

Distribution And Status Of Etheostoma Cragini Gilbert And E. Microperca Jordan And Gilbert In Arkansas, John L. Harris, Kenneth L. Smith

Journal of the Arkansas Academy of Science

No abstract provided.


Extruded Blend Of Soybean Meal And Sunflower Seeds For Dairy Cattle In Early Lactation, James K. Drackley Jan 1985

Extruded Blend Of Soybean Meal And Sunflower Seeds For Dairy Cattle In Early Lactation, James K. Drackley

Electronic Theses and Dissertations

An extruded blend of 44% crude protein soybean meal (50%), sunflower seeds (45%), and premix (5%) was evaluated as a protein and energy source for dairy cows in early lactation. Thirty Holstein cows (24 multiparos and 6 primiparous) were assigned to either a corn-oats-soybean meal concentrate (SBM) or a concentrate where soy-sunflower blend replaced all soybean meal and portions of corn and oats (SSF). Dry matter of total mixed diets was 36% corn silage, 21% alfalfa haylage, and 43% concentrate. Yields of milk (33.6 and 33.8 kg/day) and 4% fat-corrected milk (30.9 and 30.5 kg/day) were similar for cows fed …


Protected Methionine And Heat-Treated Soybean Meal For High-Producing Dairy Cows, Che-Ming Jimmy Yang Jan 1985

Protected Methionine And Heat-Treated Soybean Meal For High-Producing Dairy Cows, Che-Ming Jimmy Yang

Electronic Theses and Dissertations

The effectiveness of a rumen-protected methionine preparation was studied as an amino acid source for high-producing dairy cows during wk 4 through 16 postpartum. Twenty-four Holstein cows (14 primiparous and 10 multiparous) were fed concentrate containing heat-treated· soybean meal without or with 50 g/cow/day of added ruminally protected methionine product which provided 15 g of added DL-methionine daily. Cows were fed 16% crude protein mixed diets containing 30% of dry matter as corn silage, 15% as alfalfa hay, and 55% as concentrate. Milk production and composition were adjusted for pretreatment values (3 wk postpartum) by analysis of covariance. Adjusted milk …


Analysis Of Arkansas Fur Harvest Records - 1942-1984: Iii. Harvest-Price Relationships, Joseph D. Clark, Gary A. Heidt, Tina Sheldon, James H. Peck Jan 1985

Analysis Of Arkansas Fur Harvest Records - 1942-1984: Iii. Harvest-Price Relationships, Joseph D. Clark, Gary A. Heidt, Tina Sheldon, James H. Peck

Journal of the Arkansas Academy of Science

Correlation and linear regression analyses between mean annual pelt price and total harvest of 13 Arkansas furbearer species between 1965 and 1983 were performed for state and regions (Ozark Mountains, Ouachita Mountains, Gulf Coastal Plain, and Mississippi Delta). Statewide, strong correlations (r > 0.80) were identified for bobcat (Felis rufus), coyote (Canis latrans), gray fox (Urocyon cinereoargenteus), mink (Mustela vison), nutria (Myocastor coypus), opossum (Didelphis virginiana), and raccoon (Procyonlotor). Moderate correlations (r = 0.55 - 0.79) were identified for eastern spotted skunk (Spilogale putorius), muskrat (Ondatra zibethicus), river otter (Lutra canadensis), and striped skunk (Mephitis mephitis). Nonsignificant correlations (r < 0.468) were shown for beaver (Castor canadensis) and long-tailed weasel (Mustela frenata). Regional differences were noted for each species.


Camp-Dependent Protein Kinase Activation Lowers Hepatocyte Camp, Jackie D. Corbin, Stephen J. Beebe, Peter F. Blackmore Jan 1985

Camp-Dependent Protein Kinase Activation Lowers Hepatocyte Camp, Jackie D. Corbin, Stephen J. Beebe, Peter F. Blackmore

Bioelectrics Publications

Rat hepatocyte protein kinase was activated by incubating the cells with various cAMP analogs. Boiled extracts were then prepared and Sephadex G-25 chromatography was carried out. The G-25 procedure separated the analogs from cAMP since the resin had the unexpected property of binding cyclic nucleotides with differing affinities. Separation was necessary because the analogs would otherwise interfere with the sensitive protein kinase activation method developed for assay of cAMP. The cAMP analogs, but not 5'-AMP, lowered basal cAMP by 50-70%. The effect was rapid, analog concentration-dependent, and occurred parallel with phosphorylase activation, suggesting that the cAMP analogs act through cAMP-dependent …


Discriminative Insulin Antagonism Of Stimulatory Effects Of Various Camp Analogs On Adipocyte Lipolysis And Hepatocyte Glycogenolysis, Stephen J. Beebe, J. Bruce Redmon, Peter F. Blackmore, Jackie D. Corbin Jan 1985

Discriminative Insulin Antagonism Of Stimulatory Effects Of Various Camp Analogs On Adipocyte Lipolysis And Hepatocyte Glycogenolysis, Stephen J. Beebe, J. Bruce Redmon, Peter F. Blackmore, Jackie D. Corbin

Bioelectrics Publications

Although insulin effectively blocked hormone-stimulated glycerol output in adipocytes or phosphorylase activation in hepatocytes, the inhibitory effect of insulin on cAMP analog-stimulated cells depended on the cAMP analog used. Of the 20 analogs tested in adipocytes and 13 tested in hepatocytes, the effects of about half of them were effectively blocked by insulin, whereas the effects of many of them were not inhibited at all. In order to approach the explanation for this discriminative insulin action, the inhibitory effects of insulin on the responses to the analogs in the intact cells were correlated with the in vitro cAMP analog specificity …


Morfología Y Funciones Del Conducto De Müller De Chthonerpeton Indistinctum (Reinhardt Y Lutken, 1862) (Amphibia: Gymnophiona) En Relación Con Los Mecanismos Reproductivos De La Especie, Nibia Berois, Rafael O. De Sá Jan 1985

Morfología Y Funciones Del Conducto De Müller De Chthonerpeton Indistinctum (Reinhardt Y Lutken, 1862) (Amphibia: Gymnophiona) En Relación Con Los Mecanismos Reproductivos De La Especie, Nibia Berois, Rafael O. De Sá

Biology Faculty Publications

El orden Gymnophiona comprende anfibios ápodos, ciegos, de hábitos cavícolas y acuáticos. Como consecuencia de estos hábitos resulta muy difícil su colecta, lo cual redunda en un escaso conocimiento de la biología del orden y sobre las relaciones filogenéticas del mismo.

Una de las características más particulares del grupo se refiere a la modalidad reproductora, ya que aproximadamente el 50% de las especies presentan viviparidad y la totalidad de ellas tienen fecundación interna. Es por esta razón que el estudio del aparato reproductor ha sido encarado por diversos autores, en especial por Wake (1968, J. Morphol. 126: 291) con una …


Estructura Del Ovario De Chthonerpeton Indistinctum (Reinhardt Y Lutken, 1862) (Amphibia: Gymnophiona) Durante La Gestación, Rafael O. De Sá, Nibia Berois Jan 1985

Estructura Del Ovario De Chthonerpeton Indistinctum (Reinhardt Y Lutken, 1862) (Amphibia: Gymnophiona) Durante La Gestación, Rafael O. De Sá, Nibia Berois

Biology Faculty Publications

La morfología e histología del ovario para varias especies del orden Gymnophiona ha sido reportada por Wake (1968, J. Morphol. 126, 291) y para C. indistinctum por los autores (1984, XXIV Reunión de Comunicaciones, Soc. Zool. Uruguay).

Continuando con los estudios sobre el aparato genital de esta especie vivípara, se presenta ahora la estructura del ovario durante la gestación.

Se procesaron con fines histológicos, ovarios de dos hembras grávidas colectadas en las costas de los Dep. Montevideo y San José en abril, 1983. El número de ejemplares trabajados es muy reducido dado lo difícil que resulta su colecta …


Response Of A Nitrifying Biofilm To Copper, Denise Moldroski Mott Jan 1985

Response Of A Nitrifying Biofilm To Copper, Denise Moldroski Mott

Masters Theses

In pure cultures of Nitrosomonas, copper is known to cause a stimulation of nitrification at low levels (≤ 0.03 mg Cu+2/1) and an inhibition affect at higher levels (≥ 0.05 mg Cu+2/1). Nitrifying activated sludges are much more tolerant of copper showing only 75% inhibition at 150mg Cu+2/1. The purpose of this paper was to determine the copper sensitivity of a nitrifying biofilm grown in a continuous flow trickling filter system.

A continuous flow trickling filter system was built using limestone chips for the biofilm substrate. The biofilm was established from secondary effluent. …


Some Effects Of Viterra 2 Hydrogel On Soil Physics And Plant Growth, Julia E. Maserang Jan 1985

Some Effects Of Viterra 2 Hydrogel On Soil Physics And Plant Growth, Julia E. Maserang

Masters Theses

The effects of hydrogel on various aspects of plant growth and soil physics were determined for Tagetes patula (marigold) and Vinca rosea growing in 'PRO-MIX' soilless potting medium.

The addition of hydrogel at various concentrations to the potting medium increased the water-holding capacity of the medium, thus extending the hours-to-wilt of plants growing in this medium. While hydrogel had no effect on plant height, flowering time, plant color, soil pH or soil nitrate concentration, plant weight and flower number did appear to increase between the control and highest hydrogel treatment. As hydrogel concentration within the medium increased, percent total seed …


Fecal Coliform Membrane Filtration Recovery Techniques, Pamela Rose Rinebold Jan 1985

Fecal Coliform Membrane Filtration Recovery Techniques, Pamela Rose Rinebold

Masters Theses

Researchers over the years have been trying to improve recovery techniques for fecal coliform bacteria. Improved techniques would provide better estimates of the number of fecal coliform bacteria as well as better estimates of fecal contamination with potential pathogenicity of food and water.

Stressed, but viable, fecal coliform bacteria if placed under the appropiate conditions, can recover, thus presenting the possibility of inadequate disinfection. Chlorine sanitization, as done in potable and wastewater treatment, is one such method of stressing bacteria.

Techniques of recovery were studied using presumably unstressed and chlorine stressed samples. Phase one of this study was the comparison …


Some Factors Affecting Male Back Space Availability In The Water Bug Belostoma Flumineum Say, Amanda M. Vandenburgh Jan 1985

Some Factors Affecting Male Back Space Availability In The Water Bug Belostoma Flumineum Say, Amanda M. Vandenburgh

Masters Theses

Various factors affecting the availability of male back space in the giant water bug, Belostoma flumineum Say, are described herein and interpreted in a manner consistent with natural selection theory. Newly emerged males are observed to breed and accept eggs sooner than newly emerged females develop an egg clutch: furthermore, newly emerged males were shown to contain motile sperm on the day of adult emergence. Newly emerged females did not contain any mature eggs until approximately six days old. It was also found that newly emerged females manufacture eggs at a linear rate of 4.8 eggs per day. Egg length …


A Comparison Of The Acidic Extracellular Polysaccharides From Rhizobium Trifolii Mutants Affected In Trifolium Repens Root Hair Curling, Brian Andrew Hanley Jan 1985

A Comparison Of The Acidic Extracellular Polysaccharides From Rhizobium Trifolii Mutants Affected In Trifolium Repens Root Hair Curling, Brian Andrew Hanley

Masters Theses

The compositions and sugar linkages of the acidic extracellular polysaccharide (EPS) from several Rhizobium trifolii mutants were compared. These mutants were derived from a wild type Rhizobium trifolii, ANU843, and are unable to cause normal root hair curling, Hac-, or nodulate clover, Nod-. Three of the mutants contain a Tn5 insertion in a 5.3 kb BglII fragment of the symbiotic plasmid (pSym). A fourth mutant is missing the pSym, which includes much of the 5.3 kb BglII fragment, both of these deletions result in Hac-Nod- phenotypes. When the 5.3 kb BglII fragment is cloned (pRT150) and reinserted into the …


A Novel New Species Of Syncephalis, Richard K. Benjamin Jan 1985

A Novel New Species Of Syncephalis, Richard K. Benjamin

Aliso: A Journal of Systematic and Floristic Botany

Syncephalis hypogena, a new species isolated from soil collected in southern California is described from cultures on Mortierella bisporalis. Salient features of its vegetative development and reproduction, both sexual and asexual, are illustrated with photographs and line drawings. The species is distinguished from all other members of the genus in typically producing merosporangia from the lower rather than the upper hemisphere of the terminal ampulla of the sporangiophore.


Comparative Nutritive Value Of Soybean Meal, Sunflower Meal, And Meat And Bone Meal For Egg Production, Smart M. Oruseibio Jan 1985

Comparative Nutritive Value Of Soybean Meal, Sunflower Meal, And Meat And Bone Meal For Egg Production, Smart M. Oruseibio

Electronic Theses and Dissertations

Two experiments were conducted over a period of two years to evaluate the comparative nutritive value of soybean meal, sunflower meal, and meat and bone meal. Experiment 1 consisted of 864 Babcock--3OO pullets randomly distributed into twelve diet treatments. Each treatment was replicated six-times with twelve birds per unit. Layers diets were formulated at 16, 14, and 12% protein levels with and without amino acid supplementation. The 12% amino acid supplemented level served as the control in the experiment. Soybean meal, sum-lower meal, and eat_ and bone meal were utilized as major sources of protein supplement in yellow-corn based diets. …