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Anatomical Diversity In Roots Of Seven Species Of Abronia From California And Its Ecological Implications, Janet S. Webster, Ruth C. Wilson Jan 1980

Anatomical Diversity In Roots Of Seven Species Of Abronia From California And Its Ecological Implications, Janet S. Webster, Ruth C. Wilson

Aliso: A Journal of Systematic and Floristic Botany

No abstract provided.


Kinetics Of Adp-Induced Human Platelet Shape Change: Apparent Positive Cooperativity, John Milton, W. Yung, C. Glushak, Mony M. Frojmovic Jan 1980

Kinetics Of Adp-Induced Human Platelet Shape Change: Apparent Positive Cooperativity, John Milton, W. Yung, C. Glushak, Mony M. Frojmovic

WM Keck Science Faculty Papers

The kinetics of ADP-induced human platelet shape change have been examined. Initial velocities of platelet shape change were estimated by two methods: 1) the slope of the initial decrease in light transmission through stirred, citrated platelet-rich plasma, and 2) direct examination of platelet morphologies by phase-contrast microscopy. In both cases, a value of the Hill coefficient, n, significantly greater than 1 is obtained (2.0 +/- 0.2 and 1.8 +/- 0.2, respectively). The observed elevated value of n is not due to a substantial fraction of the ADP being platelet bound, the presence of factors in the plasma, platelet heterogeneity, of …


Linkage Studies In Tribolium Confusum Duval (Coleoptera, Tenebrionidae), Halluma Mohamed Edongali Jan 1980

Linkage Studies In Tribolium Confusum Duval (Coleoptera, Tenebrionidae), Halluma Mohamed Edongali

Theses Digitization Project

No abstract provided.


Polyphenal Oxidase Activity And Dark Pigment Of Oospore Walls In Chara Globularis, Michael F. Glinternick Jan 1980

Polyphenal Oxidase Activity And Dark Pigment Of Oospore Walls In Chara Globularis, Michael F. Glinternick

Theses Digitization Project

No abstract provided.


Population Regulation In Wolves, Jane M. Packard, L. David Mech Jan 1980

Population Regulation In Wolves, Jane M. Packard, L. David Mech

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

The possibility of social regulation of wolf populations has been discussed in the literature for several years. Some of the first ecological studies of wolves indicated that their populations did not increase as rapidly as was theoretically possible, and that they reached a saturation point apparently not set by food. Subsequent captive studies demonstrated the existence of social mechanisms possibly capable of regulating population growth. However, the importance of these factors in wild populations has not been established. This paper has four objectives: (1) to evaluate the existing concept of "intrinsic limitation," (2) to propose that wolf population dynamics may …


Subunit Interactions And The Allosteric Response In Phosphorylase, S. Sprang, R. J. Fletterick Jan 1980

Subunit Interactions And The Allosteric Response In Phosphorylase, S. Sprang, R. J. Fletterick

Biological Sciences Faculty Publications

The contribution of intersubunit interactions to allosterically induced conformational changes in phosphorylase are considered. Phosphorylase a, Pa (phosphorylated at Ser-14), is significantly in the active (R) conformation, while phosphorylase b, Pb (nonphosphorylated), is predominantly in the inactive (T) conformation. The structure of glucose-inhibited (T) Pa has been determined at 2.5-A resolution and atomic coordinates have been measured. These data have been used to calculate the solvent accessible surface area at the subunit interface and map noncovalent interactions between protomers. The subunit contact involves only 6% of the Pa monomer surface, but withdraws an area of 4,600 A2 from solvent. The …


Botanical And Ecological Aspects Of Coastal Raised Peatlands In Maine : And Their Relevance To The Critical Areas Program Of The State Planning Office, Ian A. Worley Jan 1980

Botanical And Ecological Aspects Of Coastal Raised Peatlands In Maine : And Their Relevance To The Critical Areas Program Of The State Planning Office, Ian A. Worley

Maine Collection

Botanical and Ecological Aspects of Coastal Raised Peatlands in Maine : and Their Relevance to the Critical Areas Program of the State Planning Office.

by Ian A. Worley

A Report Prepared for the Maine Critical Areas Program, State Planning Office, 184 State Street, Augusta, Maine 04333.

Planning Report No. 69 (January 1980)

Contents: Foreword / Abstract / Table of Contents / List of Figures / List of Tables / Acknowledgements / Introduction / Natural History and Ecology of the Coastal Raised Peatlands / Selection of Coastal Peatlands Recommended for Evaluation by the Critical Areas Program / General Evaluation of Coastal …


Aquatic Insects Of Upper Three Runs Creek, Savannah River Plant, South Carolina. Part 1: Orders Other Than Diptera, John C. Morse, Jay W. Chapin, David D. Herlong, Ray S. Harvey Jan 1980

Aquatic Insects Of Upper Three Runs Creek, Savannah River Plant, South Carolina. Part 1: Orders Other Than Diptera, John C. Morse, Jay W. Chapin, David D. Herlong, Ray S. Harvey

Publications

Upper Three Runs Creek and its tributary sources, located mostly on property of the Savannah River Plant near Aiken, South Carolina (Fig. 1), is well-known as an unpolluted, blackwater drainage system which is probably typical of smaller, Sandhills waterways of primeval southeastern North America. Probably no other stream at the Plant's Flowing Stream Laboratory (or Thermal Effects Laboratory) has been documented by a research team from the Academy of Natural Sciences of Philadelphia (A.N.S.P.).


Spider Community Organization : Seasonal Variation And The Role Of Vegetation Architecture, Cynthia L. Hatley, James A. Macmahon Jan 1980

Spider Community Organization : Seasonal Variation And The Role Of Vegetation Architecture, Cynthia L. Hatley, James A. Macmahon

Green Canyon Environmental Research Area, Logan Utah

The relationship between vegetation architecture and spider community attributes were examined in a big sage community. Spiders were separated into guilds using similarities of species' hunting behavior. Shrub architecture was experimentally manipulated in the field by either clippings 50% of the shrub's foliage to decrease foliage density or tying together a shrub's branches to increase foliage density. Shrub perturbations resulted in changes in the number of spider species, spider guilds and guild importance values. The number on spider species and guilds in the tied shrubs were significantly higher than those in the clipped or control shrubs sampled. Spider species diversity …


Spatial Distribution Of Flying Southern Pine Beetle (Coleoptera:Scolytidae) And The Predator Thanasunus Dubius (Coleoptera:Cleridae), Jack E. Coster, Paul C. Johnson, Reed J. Reeve Jan 1980

Spatial Distribution Of Flying Southern Pine Beetle (Coleoptera:Scolytidae) And The Predator Thanasunus Dubius (Coleoptera:Cleridae), Jack E. Coster, Paul C. Johnson, Reed J. Reeve

Faculty Publications

Spatial dispersion patterns of flying southern pine beetles, Dendroctonus frontalis Zimm., and the clerid predator Thanasimus dubius (F.) were determined within 3 natural infestations of southern pine beetle (SPB) in eastern Texas using grids of sticky traps. There was significant positive association of the 2 insects throughout the trapping grids, although aerial population densities of the clerid were inversely related to aerial densities of SPB. Aggregation patterns were quantified using the index of patchiness (lP) and the regressions of mean crowding (m) on mean density (m). Both methods showed a highly clumped pattern for both beetle species. SPB density in …


Characterization Of Grand Fir Colonized By Nosodenron Californicum Horn (Coleoptera: Nosodendridae), David Kulhavy Jan 1980

Characterization Of Grand Fir Colonized By Nosodenron Californicum Horn (Coleoptera: Nosodendridae), David Kulhavy

Faculty Publications

In two 50-hectare forested areas in a Thuja plicata/Pachistima myrsinites habitat type, 52 grand firs, Abies grandis (Douglas) Lindley, hosts of Nosodendron californicum Horn, were located. Trees colonized by N. 'califomicum averaged 40.6 min height, 115 years in age and 59.5 em in diameter. Average elevation was 906.8 m.


Energy Values Of Nine Populus Clones, Terry F. Strong Jan 1980

Energy Values Of Nine Populus Clones, Terry F. Strong

Aspen Bibliography

Compares calorific values for components of nine Populus clones. The components include stem wood, stem bark, and branches. Also compares calorific values for clones of balsam poplar and black cottonwood parentages.


Studies On The Structure Of Human Fibronectin, Martha B. Furie Jan 1980

Studies On The Structure Of Human Fibronectin, Martha B. Furie

Student Theses and Dissertations

Plasma fibronectin is a glycoprotein that consists of two polypeptide chains of approximately 250,000 and 245,000 daltons, joined by disulfide bonds located near one end of the molecule. Fibronectin was isolated from human plasma by gelatin-agarose affinity chromatography and DEAE-cellulose ion exchange chromatography. The two subunit chains were found to be similar or identical with respect to primary structure, using a one-dimensional peptide mapping technique. Purified plasma fibronectin was cleaved with human α-thrombin, and three major fragments were recovered: two large ones with molecular weights of approximately 230,000 and 235,000, and a small one with a molecular weight of 29,000. …


Edging Toward Extinction: The Status Of Wildlife In Latin America, Douglas R. Shane Jan 1980

Edging Toward Extinction: The Status Of Wildlife In Latin America, Douglas R. Shane

eBooks

No abstract provided.


A Limnological Study Of 43 Selected Maine Lakes, Derrill J. Cowing, Matthew Scott Jan 1980

A Limnological Study Of 43 Selected Maine Lakes, Derrill J. Cowing, Matthew Scott

Maine Collection

A Limnological Study of 43 Selected Maine Lakes

by Derrill J. Cowing and Matthew Scott

U.S. Geological Survey : Water-Resources Investigations 80-69

Prepared in cooperation with the Maine Department of Environmental Protection

U.S. Geological Survey, 26 Ganneston Drive, August, Maine 04330


Acetoacetate Decarboxylase Activity Of Fraction V Human Serum Albumin, Robert Richard Rosecrans Jan 1980

Acetoacetate Decarboxylase Activity Of Fraction V Human Serum Albumin, Robert Richard Rosecrans

Dissertations

No abstract provided.


Effects Of Chemoreceptor And Baroreceptor Inputs On The Termination Of Inspiration, Dexter Franklin Speck Jan 1980

Effects Of Chemoreceptor And Baroreceptor Inputs On The Termination Of Inspiration, Dexter Franklin Speck

Dissertations

No abstract provided.


Peptide Analyses Of Streptococcal M-Proteins, James Thaddeus Zmuda Jan 1980

Peptide Analyses Of Streptococcal M-Proteins, James Thaddeus Zmuda

Dissertations

No abstract provided.


The Role Of Skin Temperature In The Control Of Sweating In Man, Thomas V. Mccaffrey Jan 1980

The Role Of Skin Temperature In The Control Of Sweating In Man, Thomas V. Mccaffrey

Dissertations

No abstract provided.


Opiates And Neuro-Effector Transmission In The Mouse Vas Deferens: Intracellular Recordings Of Excitatory Junction Potentials, Lauren Vaile Vitek Jan 1980

Opiates And Neuro-Effector Transmission In The Mouse Vas Deferens: Intracellular Recordings Of Excitatory Junction Potentials, Lauren Vaile Vitek

Dissertations

No abstract provided.


The Influence Of Cardiac Sympathetics And Periods Of Ischemic Insult Upon Myocardial Blood Flow, Incidence Of Arrhythmia, Electrical Activity And Myocardial Infarction During Coronary Occlusion, Michael J. Barber Jan 1980

The Influence Of Cardiac Sympathetics And Periods Of Ischemic Insult Upon Myocardial Blood Flow, Incidence Of Arrhythmia, Electrical Activity And Myocardial Infarction During Coronary Occlusion, Michael J. Barber

Dissertations

No abstract provided.


Notes On The Northern Gulf Of Mexico Occurrence Of Sagitta Friderici Ritter-Zahony (Chaetognatha), Jerry A. Mclelland Jan 1980

Notes On The Northern Gulf Of Mexico Occurrence Of Sagitta Friderici Ritter-Zahony (Chaetognatha), Jerry A. Mclelland

Gulf and Caribbean Research

The neritic chaetognath Sagitta friderici Ritter-Zahony, 1911 was identified in plankton samples from the northern Gulf of Mexico in June 1974. Specimens analyzed from two groups of adults ranged from 6 to 13.7 mm long. Meristic values did not appear to be a function of body length except for individuals in the 12.4 to 13.7 mm range that had larger numbers of hooks and teeth.

Adults of Sagitta friderici and the closely related S. tenuis Conant, 1896 were compared and found to be distinguishable chiefly by (1) the number of ova per unit length of the ovary, and (2) the …


Diatoms In The Gills Of The Commercial White Shrimp, Robin M. Overstreet, Susan Safford Jan 1980

Diatoms In The Gills Of The Commercial White Shrimp, Robin M. Overstreet, Susan Safford

Gulf and Caribbean Research

A white shrimp from Galveston, Texas, is the first reported case of a crustacean internally infected by a diatom. Even though more than one species occurred in debris on and between gill filaments, only individuals of Amphora sp. occurred within gills. To determine if a related diatom would easily reproduce within the shrimp and cause. a host-response similar to that observed, we injected cultured specimens of A. coffaeformis into white shrimp. Under the experimental conditions, individuals of that species did not divide, but they elicited an extensive melanistic host-response.


Age-Season Adjustment Factors For Alpine, Lamancha, Nubian, Saanen, And Toggenburg Dairy Goats, M. U. Iloeje, T. R. Rounsaville, R. E. Mcdowell, G. R. Wiggans, L. Dale Van Vleck Jan 1980

Age-Season Adjustment Factors For Alpine, Lamancha, Nubian, Saanen, And Toggenburg Dairy Goats, M. U. Iloeje, T. R. Rounsaville, R. E. Mcdowell, G. R. Wiggans, L. Dale Van Vleck

Department of Animal Science: Faculty Publications

Multiplicative age-season adjustment factors for milk and fat yields of five breeds of dairy goats were estimated by fitting a three-way, mixed classification model containing random effects for does with fixed effects for herd-year-season and age-season for 7544, 1994, 7456, 3307, and 4599 lactation records collected from 1965 to 1976 from Alpine, La- Mancha, Nubian, Saanen, and Toggenburg dairy goats in the United States. These factors reflect changes in milk and fat yields associated with age and season of freshening. As with dairy cattle, these factors indicated that milk records of goats are affected differently in different seasons for a …


Influence Of Lactobacillus Acidophilus Inoculum On Gnotobiotic And Conventional Pigs, D. S. Pollmann, D. M. Danielson, W. B. Wren, E. R. Peo, Jr., K. M. Shahani Jan 1980

Influence Of Lactobacillus Acidophilus Inoculum On Gnotobiotic And Conventional Pigs, D. S. Pollmann, D. M. Danielson, W. B. Wren, E. R. Peo, Jr., K. M. Shahani

Department of Animal Science: Faculty Publications

Two trials were conducted to determine the effect of L. acidopbilus (bacteria commonly found in probiotics) inoculum on gnotobiotic and conventional pigs. The localization and population levels of L. acidopbilus (LA) in the gastrointestinal (GI) tract of 24 gnotobiotic pigs (12 treated and 12 control) were determined by microbiological techniques.


Lysine Requirement Of Pigs Weighing 5 To 15 Kg Fed Practical With And Without Added Fat, A. J. Lewis, E. R. Peo, Jr., B. D. Moser, T. D. Crenshaw Jan 1980

Lysine Requirement Of Pigs Weighing 5 To 15 Kg Fed Practical With And Without Added Fat, A. J. Lewis, E. R. Peo, Jr., B. D. Moser, T. D. Crenshaw

Department of Animal Science: Faculty Publications

Weanling crossbred pigs (average weight 5 kg) were fed diets containing two levels of fat and six levels of lysine in a 2 • 6 factorial design to determine the lysine requirement of young pigs fed practical diets with and without added fat. The diets were based on corn and soybean meal and contained either 5% sucrose or 5% lard. Lysine levels ranged from .95% (basal) to 1.45% in .10% increments. The growth trial was 28 days long and pigs were bled at 14 and 28 days. Feed intake (ADFI), weight gain (ADG), feed efficiency (G:F) and changes in plasma …


Optimal Foraging In A Uniform Habitat: The Search Mechanism Of The Green Lacewing, Alan B. Bond Jan 1980

Optimal Foraging In A Uniform Habitat: The Search Mechanism Of The Green Lacewing, Alan B. Bond

Alan Bond Publications

The effects of food deprivation and prey contact on the components of searching behavior in larval green lacewings (Chrysopa carnea Stephens) were examined to test the applicability of optimal foraging theory to predation in a uniform habitat. Variation in foraging intensity was primarily the result of changes in the meander. Modulation of the response to prey contact with increasing deprivation involved changes in the velocity and the response persistence and suggested the occurrence of adaptation to inferred differences in the spatial distribution of the prey. The ratio of giving-up times at different levels of deprivation was in accordance with …


G80-504 Proper Livestock Grazing Distribution On Rangeland (Revised February 1996), Jerry D. Volesky, Walter H. Schacht, Steven S. Waller Jan 1980

G80-504 Proper Livestock Grazing Distribution On Rangeland (Revised February 1996), Jerry D. Volesky, Walter H. Schacht, Steven S. Waller

University of Nebraska-Lincoln Extension: Historical Materials

Good grazing distribution can increase harvest efficiency and grazing capacity. This NebGuide discusses common grazing problems and offers solutions.

The 23 million acres of rangeland in Nebraska are mostly grassland and are primarily devoted to forage production for Nebraska's multibillion dollar beef cattle industry. Nebraska's rangelands are inherently productive, and potential returns from efficient management practices are high for livestock producers.

Proper grazing distribution is a factor which can increase livestock production from Nebraska's rangeland. Grazing distribution refers to dispersion of grazing animals over a management unit. It is just one element of good grazing management which should also include …


Farm, Ranch And Home Quarterly Institute Of Agriculture And Natural Resources, University Of Nebraska- Lincoln Jan 1980

Farm, Ranch And Home Quarterly Institute Of Agriculture And Natural Resources, University Of Nebraska- Lincoln

Farm, Ranch and Home Quarterly

In this issue

: Market Center Proposed...................................... 2

Founder-Researchers Seek Baseline Information .......................... 3

Research Digest .......................................... 4

'Technical Assistance is Key In Food Production Development ......................... 6

Botulism-A Big Problem in a Small Package ........................ 8

Pen of Three-Youth Experience in Beef Production ...................................... 11

Applicators Tested for Soybean Herbicide Control ...................................... 12

Fuel Survey-Keeping Tabs on Energy Use ................... 14

Creativity in Young Children .............................. 16

Education Importance and Satisfaction- QUALITY OF LIFE................................ 18

Alexandria: A Study in Community Development .......................................... 22


Identification Of Mosquitoes Of Anopheles Gambiae Species Complex A And B By Analysis Of Cuticular Components, D. A. Carlson, M. W. Service Jan 1980

Identification Of Mosquitoes Of Anopheles Gambiae Species Complex A And B By Analysis Of Cuticular Components, D. A. Carlson, M. W. Service

Entomology Papers from Other Sources

Two important vectors of malaria in Africa, Anopheles gambiae and Anopheles arabiensis (Diptera: Culicidae), often occur sympatrically and cannot be distinguished morphologically. A chemical method was developed to identify individual laboratory-reared adult males or females of either species by extraction and analysis of cuticular components with gas chromatography. Statistically significant differences were seen between species when selected pairs of peaks were compared.