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Full-Text Articles in Physical Sciences and Mathematics

Erratum: On Improved Wkb (Uniform Asymptotic) Quantum Conditions, Dunham Corrections, The Langer Modification, And Rkr Potentials, Russell T. Pack Nov 1974

Erratum: On Improved Wkb (Uniform Asymptotic) Quantum Conditions, Dunham Corrections, The Langer Modification, And Rkr Potentials, Russell T. Pack

Faculty Publications

In Eqs. (28) and (29) p should be changed to t.


Metabolic Capabilities Of Sulfur Oxidizing Bacteria And Their Role In Water Pollution, M. I. H. Aleem Sep 1974

Metabolic Capabilities Of Sulfur Oxidizing Bacteria And Their Role In Water Pollution, M. I. H. Aleem

KWRRI Research Reports

This report describes investigations into the physiology of microorganisms that are commonly involved in the oxidation of inorganic sulfur compounds. The metabolic activities of these bacteria play a potent role in several fields of economic importance such as strip mining operations, water pollution, corrosion, metallurgy, petroleum technology and soil fertility processes.

The oxidation of inorganic sulfur compounds was studied in the chemolithotrophs Thiobacillus denitrificans, Thiobacillus A2, Thiobacillus neapolitanus, and a photolithotroph Rhodopseudomonas palustris. Cell suspensions from all of the thiobacilli catalyzed completely the oxidation of sulfide, thiosulfate, and sulfite to sulfate. The oxidation of thiosulfate in R. palustris …


Coastal Vegetational Communities Of The Two Texas Barrier Islands, Boca Chica And Brazos, Baltazar Cisneros Aug 1974

Coastal Vegetational Communities Of The Two Texas Barrier Islands, Boca Chica And Brazos, Baltazar Cisneros

Theses and Dissertations - UTB/UTPA

Two Texas barrier islands, Boca Chica and Brazos, have unique coastal vegetational communities that may be Influenced by several environmental factors. These environmental factors include temperature, precipitation, wind speed, sunshine exposure, day length, and dune height. The purpose of this investigation was to determine the total number of coastal plant species per station, season, and year and to consider environmental factors that may significantly affect the number and pattern of coastal species. Coverage comparison between aerial and land sampling and aerial vegetational zonation was also considered.

Results indicated the presence of 21 angiosperm families and a total of 54 species. …


The Benthic Communities Of The Eastern Rocky Shore Areas Of Goshen Bay, Utah Lake, Thomas Whitney Toole Aug 1974

The Benthic Communities Of The Eastern Rocky Shore Areas Of Goshen Bay, Utah Lake, Thomas Whitney Toole

Theses and Dissertations

Information about the benthic macroinvertebrate populations along the eastern shore of Goshen Bay, Utah Lake, Utah, can be used, in part, to determine future management of the lake. In the project herein reported, cement artificial substrate samplers were used to sample two types of substrate: rubble and compacted calcareous tufa. Monthly samples were obtained from each type of substrate from March 1972 to May 1973. An amphipod, Hyalela azteca and a chironomid, Dicrotendipes fumidus were the dominant organisms in numbers and tiomass. Amphipod numbers were dependent upon the amount of algal standing crop. Elimination of this area could affect the …


Metabolism Of 3-Isopropyl-4h-2,1,3-Benzothiadiazin-4-(3h)-One-2,2-Dioxide (Bentazon) In Agitated And Non-Agitated Sediment, David Cortez Gutierrez Aug 1974

Metabolism Of 3-Isopropyl-4h-2,1,3-Benzothiadiazin-4-(3h)-One-2,2-Dioxide (Bentazon) In Agitated And Non-Agitated Sediment, David Cortez Gutierrez

Theses and Dissertations

Bentazon, (3-isopropyl-1H-2,1,3-benzothiadiazin-4(3H)-l-2,2-dioxide) a new experimental herbicide, was studied under the effects of sterile and non-sterile conditions, 12 hours light: 12 hours dark and totally dark conditions, and agitated and non-agitated conditions in aquatic sediment. The effects of the different levels of BOD/COD values on the decomposition of Bentazon were studied. Photoperiod, sterility, and BOD/COD levels appeared to have no influence in the breakdown of Bentazon. Agitation-time interaction appeared to be the only factor that influenced the more rapid degradation of Bentazon. Bentazon was the major 14C-residue found in the water; it was followed by an unknown. The third major metabolite …


Nutrient And Energy Composition Of Beef Cattle Feedlot Waste Fractions, C. B. Gilbertson, J. A. Nienaber, J. R. Ellis, T. M. Mccalla, T. J. Klopfenstein, S. D. Farlin Jul 1974

Nutrient And Energy Composition Of Beef Cattle Feedlot Waste Fractions, C. B. Gilbertson, J. A. Nienaber, J. R. Ellis, T. M. Mccalla, T. J. Klopfenstein, S. D. Farlin

Nebraska Agricultural Experiment Station: Historical Research Bulletins

This bulletin describes nutrient and energy composition of beef cattle waste fractions as a function of the ration roughage level and type of feedlot. Results can be used to plan engineering system approaches and research to develop handling and processing equipment necessary for recovery of the most valuable portion of waste.


Feeding And Food Preferences By Three Sympatric Species Of Cyprinodontid Fishes, Lawrence J. Baer Jul 1974

Feeding And Food Preferences By Three Sympatric Species Of Cyprinodontid Fishes, Lawrence J. Baer

OES Theses and Dissertations

The feeding and food utilization by three sympatric species of cyprinodontid fishes was examined using a modified Ivlev Electivity Co-efficient. Results indicated that although Fundulus heteroalitus and Fundulus majalis are sympatric in the area examined,their usage of the available food source varied noticeably. The third investigated species, Cyprinodon variegatus, fed mainly upon a vegetal detritus food source varied by the consumption of invertebrate and vertebrate food items. Slight intra-specific variances of diet between crespuscular periods was also discussed.


Annual Report 1973-74 And Membership Directory, Iowa Academy Of Science Jun 1974

Annual Report 1973-74 And Membership Directory, Iowa Academy Of Science

Iowa Academy of Science Documents

Contents:

Committee Membership 1973-74 ... 1-3
Report of the Executive Secretary ... 4
Minutes of the Annual Business Meeting ... 20
Report of the Treasurer ... 32
Report of the Annual Meeting Committee ... 34
Report of the Editor of the Proceedings ... 35
Report of the Editor of the Iowa Science Teachers Journal ... 36
Report of the Librarian ... 37
Report of the Finance Committee ... 38
Report of the Elections Committee ... 40
Report of the Membership Committee ... 42
Report of the Publications Committee ... 44
Report of the Recognition and Awards Committee ... 46
Report …


The Prairie Naturalist Volume 6, No.2. June 1974 Jun 1974

The Prairie Naturalist Volume 6, No.2. June 1974

The Prairie Naturalist

WOOD DUCKS IN NORTH DAKOTA ▪ H. A. Doty

AERIAL FEEDING BY RED-WINGED BLACKBIRDS NEAR FULLER'S LAKE, NORTH DAKOTA ▪ W. C. Royall, Jr. & O. E. Bray

ARBOREAL WOODCHUCKS? ▪ K. T. Killingbeck

IMAGES, CHOICE, AND COMMUNITY DEVELOPMENT ▪ E. Smith

BREEDING STATUS OF THE LEAST BITTERN IN NORTH DAKOTA ▪ C. L. Cink

NOTE: Maximum Sizes for Ambystomatid Salamanders ▪ D. W. Larson


Nutrition Of Sheep Grazing Foothill Big Game Range In Spring, Kurt J. Kotter May 1974

Nutrition Of Sheep Grazing Foothill Big Game Range In Spring, Kurt J. Kotter

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Sheep with esophageal fistulas were used to determine the daily intake, nutritive content and digestibility of forage at three periods and two stocking intensities during the spring of 1972 on a typical foothill range in northern Utah.

Heavy grazing under a season-long regime did not influence the concentrations of dietary chemical components when compared to moderate grazing; however, it did depress the digestibility of cellulose and organic matter. There was a significant decline in the dietary chemical components due to forage maturation. Digestibility of organic matter and cellulose were significantly higher in the early spring as compared to late spring. …


Effects Of Cocaine, Nicotine And Diet On Voluntary Alcohol Consumption In Rats, Zaida Raquel Cordero Loayza May 1974

Effects Of Cocaine, Nicotine And Diet On Voluntary Alcohol Consumption In Rats, Zaida Raquel Cordero Loayza

Loma Linda University Electronic Theses, Dissertations & Projects

The consumption of alcohol is a problem not only in this country (U.S.), but also in many other places in the world. Thus we find the Indians in Peru, Bolivia and other neighboring countries (Ecuador and northern part of Argentina) consuming alcohol to the point that they become alcoholics, in addition to this they also chew coca leaves, plant from which cocaine is extracted.

In an effort to establish the cause for this behavior, we put Sprague-Dawley albino rats on either a poor or good basal diet. Once every other day the rats were injected with a solution of cocaine. …


Seed Reserves In Desert Soils, David W. Goodall, Suzanne J. Morgan May 1974

Seed Reserves In Desert Soils, David W. Goodall, Suzanne J. Morgan

Memorandum

Soil and litter samples were collected from the playa, playa fringe and bajada zones of the Jornada Validation Site. These samples were analyzed for their seed content, special attention being paid to spatial distribution. At the time of sampling, there was little litter on the soil surface, and the litter contained only a small proportion of the total seeds present.


The Fresh-Water Mussel Industry Of The Lower Tennessee River: Ecology & Future, Randall Grace May 1974

The Fresh-Water Mussel Industry Of The Lower Tennessee River: Ecology & Future, Randall Grace

Masters Theses & Specialist Projects

The fresh-water mussel industry of the Tennessee River is nearing an end. Overharvesting, habitat alterations, and pollution are the major contributors to the depletion of the mussel resource, upon which the shell industry is based. A history of unconcern by shell harvesters and weak conservation enforcement by governmental agencies, has left the major waterways of the United States nearly void of commercial clams. The lower Tennessee River presently supplies the mussel industry with nearly all the important species of mollusks. If this industry is to be maintained in the United States, ways to preserve and propagate the mussel population must …


A Study Of The Radiation Quality Under Plant Canopies In The Wave Range 0.4 To 2.5 Microns, Nolasco G. Baldazo May 1974

A Study Of The Radiation Quality Under Plant Canopies In The Wave Range 0.4 To 2.5 Microns, Nolasco G. Baldazo

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The spectral distribution of the global radiation from 0.4 to 2.5 microns penetrating deciduous and coniferous canopies were measured during clear days between 10 a.m. and 2 p.m. using a double-quartz monochromator.

In the visible region (0.4 to 0.7 micron) the average relative spectral transmissions under both canopies are about one percent beginning at 0.4 micron and decreasing to about half a percent at 0.67 micron. There is only a small peak in the green (0.55 micron) transmission under deciduous stands while there is none under coniferous canopies. The slightly higher transmission in the blue (0.4 micron) is attributed to …


The Dynamics Of Root Growth And The Partitioning Of Photosynthates In Cool Desert Shrubs, Osvaldo Alberto Fernandez May 1974

The Dynamics Of Root Growth And The Partitioning Of Photosynthates In Cool Desert Shrubs, Osvaldo Alberto Fernandez

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study addresses the nature of physiological and phenological evolutionary strategies of root growth dynamics and energy allocation followed by Atriplex confertifolia, Ceratoides lanata, and Artemisia tridentata growing in their natural cool desert environment.

Root observation chambers with inclined Plexiglass windows were installed in monospecific desert communities of Atriplex confertifolia, Ceratoides lanata and Artemisia tridentata. Soil temperature and water potential measurements taken immediately adjacent to the observation windows indicated a minimal disturbance was caused by the presence of these chambers. For the three species initiation of root growth was observed before initiation of shoot activity, furthermore, active root growth extended …


An Evaluation Of In-Stream Structures Designed To Provide Fish Habitat, Charles H. Call Jr. May 1974

An Evaluation Of In-Stream Structures Designed To Provide Fish Habitat, Charles H. Call Jr.

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In-stream concrete structures were studied through model tests and river tests. The model studies indicated that four designs provided good habitat in the model stream. These structures were the inverted weir, the "V" structure, the slab with legs and the cylinder. Through the river studies it was determined that these structures did not influence enough of the total river area to be effective in providing good fish habitat. Also an appreciable amount of yearly maintenance would be required to free the structures from silting in, debris, and vandalism. The slab with legs was the only promising structure.


Abstracts Of Papers Scheduled For Presentation At The 86th Session Of The Iowa Academy Of Science, April 19-20, 1974, Iowa Academy Of Science Apr 1974

Abstracts Of Papers Scheduled For Presentation At The 86th Session Of The Iowa Academy Of Science, April 19-20, 1974, Iowa Academy Of Science

Iowa Academy of Science Documents

Presentation abstracts from the annual meeting of the Iowa Academy of Science


86th Annual Session Of The Iowa Academy Of Science, April 19-20, 1974, Iowa Academy Of Science Apr 1974

86th Annual Session Of The Iowa Academy Of Science, April 19-20, 1974, Iowa Academy Of Science

Iowa Academy of Science Documents

No abstract provided.


Finitely Generated Modules Over Bezout Ringsrwiegand@Unl.Edu, Roger Wiegand, Sylvia Wiegand Apr 1974

Finitely Generated Modules Over Bezout Ringsrwiegand@Unl.Edu, Roger Wiegand, Sylvia Wiegand

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Let R be a Bezout ring (a commutative ring in which all finitely generated ideals are principal), and let M be a finitely generated R -module. We will study questions of the following sort: (A) If every localization of M can be generated by n elements, can M itself be generated by n elements? (B) If M 0 R m = Rn for some m, n, is Af necessarily free? (C) If every localization of M has an element with zero annihilator, does M itself have such an element? We will answer these and related questions for various familiar classes …


Oyster Spatfall On Shellstrings In Virginia Rivers: 1973 Annual Summary, Dexter S. Haven, Paul C. Kendall Apr 1974

Oyster Spatfall On Shellstrings In Virginia Rivers: 1973 Annual Summary, Dexter S. Haven, Paul C. Kendall

Reports

Although oyster setting levels in most Virginia river systems are still far below trose whicb commonly occurred prior to 1960, the 1973 season marked an improvement over the previous year when Tropical Storm Agnes raged througb the Chesapeake Bay region, creating adverse environmental conditions which were largely responsible_ for the_ lowest s},tting levels on record, Data for 1972,


The Use Of Color Infrared Aerial Photography In Determining Salt Marsh Vegetation And Delimiting Man-Made Structures Of Lynnhaven Bay, Virginia, Robert E. Holman Lll Apr 1974

The Use Of Color Infrared Aerial Photography In Determining Salt Marsh Vegetation And Delimiting Man-Made Structures Of Lynnhaven Bay, Virginia, Robert E. Holman Lll

Biological Sciences Theses & Dissertations

Color infrared aerial photography was found to be superior to color aerial photography in an ecological study of Lynnhaven Bay, Virginia. The research was divided into three phases: 1) determination of the feasibility of correlating color infrared aerial photography with wetland species composition and zonation patterns, 2) determination of the accuracy of the aerial interpretation and problems related to the aerial method used, and 3) comparison of developed with undeveloped areas along Lynnhaven Bay's shoreline.

Wetland species composition and zonation patterns of major cones were correlated with aerial infrared photography and resulted in a high degree of accuracy. Problems with …


Studies On The Causes Of Tree Distribution In A Forest Type In The Dismal Swamp National Wildlife Refuge, Thomas A. Janszen Apr 1974

Studies On The Causes Of Tree Distribution In A Forest Type In The Dismal Swamp National Wildlife Refuge, Thomas A. Janszen

Biological Sciences Theses & Dissertations

Vegetational composition and environmental parameters were analyzed in a forest type of the Dismal Swamp. A 0.5 ha forest stand was divided into 200 5 x 5 meter contiguous quadrats and the tree size classes were precisely mapped. Fifty soil samples were analyzed for texture, pH, and major nutrients. A topographic map was constructed with precision to 0.01 ft. Analysis of variance tests showed non-randomness to exist in soil texture and nutrient content while homogeneity tests showed non-randomness in distribution of some woody species. Factor analysis indicated no significant correlations between soil quality, topography, and woody species. Findings indicate that …


An Ecological Study Of The Craney Island Disposal Area In Hampton Roads, Virginia, David Wallace Laist Apr 1974

An Ecological Study Of The Craney Island Disposal Area In Hampton Roads, Virginia, David Wallace Laist

Biological Sciences Theses & Dissertations

A one year ecological study was conducted on the Craney Island Disposal Area in Hampton Roads, Virginia. This study attempted to identify the flora and fauna inhabiting the spoil deposits and trace the development of communities from the time of deposition through the initial stages of succession.

One hundred and ninety-two species were identified including 48 vascular plants, 66 insects, 48 birds, 18 species of algae, 4 crustaceans, and 8 vertebrates. The study area was divided into six zones based on substrate characteristics and species composition. The successional patterns and biotic interactions within each zone were discussed.


Observations On The Distribution And Composition Of Zooplankton In Portions Of The Intracoastal Waterway, Virginia, O. Clair Hillard Jr. Apr 1974

Observations On The Distribution And Composition Of Zooplankton In Portions Of The Intracoastal Waterway, Virginia, O. Clair Hillard Jr.

Biological Sciences Theses & Dissertations

Five stations were established in the Southern Branch of the Elizabeth River, the Dismal Swamp Canal, the Albemarle and Chesapeake Canal and the North Landing River. Representative samples of zooplankton were taken from October 1971 to June 1972. A. total of 57 species were identified and discussions regarding seasonal distribution in relation to physical factors and circulation are presented.

The composition of the zooplankton was found to fluctuate greatly due to the variables characteristic of the study area. The combined effect of tidal flow with freshwater input in conjunction with drainage from the Great Dismal Swamp, results in isolated populations …


The Prairie Naturalist Volume 6, No.1. March 1974 Mar 1974

The Prairie Naturalist Volume 6, No.1. March 1974

The Prairie Naturalist

AVIAN MORTALITY FROM COLLISIONS WITH OVERHEAD WIRES IN NORTH DAKOTA ▪ G. L. Krapu

NOTES ON THE BIOLOGY OF THE OLIVE-BACKED POCKET MOUSE PEROGNATHUS FASCIATUS ON THE NORTHERN GREAT PLAINS ▪ J. E. Pefaur & R. S. Hoffman

NOTE: Swans Resting on the Surface of A Dry Lake ▪ D. S. Gilmer


Seasonal Changes In Water Quality And Primary Productivity In Doe Valley Lake, Edmond J. Bacon, Stuart E. Neff Mar 1974

Seasonal Changes In Water Quality And Primary Productivity In Doe Valley Lake, Edmond J. Bacon, Stuart E. Neff

KWRRI Research Reports

Primary productivity and water quality were studied in Doe Valley Lake, a 147-hectare impoundment on Doe Run, a spring-fed stream in Meade County, Kentucky, from 13 June 1969 to 31 July 1972. Doe Valley Lake is monomictic during most winter seasons, but it is dimictic during more severe winters because of its morphometry and location on the borderline climatic region for dimictic lakes (37° N latitude). Oxygen depletion in the hypolimnion is severe, and anaerobic conditions usually prevail by late June. A hypolimnetic areal deficit of 0.038 mg/cm2/day was calculated. Supersaturation of oxygen in the epilimnion was common, …


Development Of Prediction Relationships For Water Requirements With Irrigation Cooling, Billy J. Barfield, John N. Walker, F. A. Payne Feb 1974

Development Of Prediction Relationships For Water Requirements With Irrigation Cooling, Billy J. Barfield, John N. Walker, F. A. Payne

KWRRI Research Reports

A model for predicting leaf temperatures during an off-on mist cycle is presented. The model uses a combination of energy budget and aerodynamic techniques. The model was tested for dry leaf temperature and evapotranspiration predictions using average hourly data from Arizona. The accuracy was good. It was also tested for dry leaf temperature predictions using two to three minute data with a widely varying net radiation. When reasonable values of stomatal resistance were used, the agreement was again good.

The model was tested for prediction of wet leaf temperature prediction with a ten minute on, fifty minute off mist irrigation …


Lupin Agronomy: Time Of Planting, Seeding Rate And Variety In A Long Season Area., M. W. Perry Jan 1974

Lupin Agronomy: Time Of Planting, Seeding Rate And Variety In A Long Season Area., M. W. Perry

Experimental Summaries - Plant Research

To evaluate lupin varieties and agronomic practices in a long season district using a factorial experimental design. 74A16a Location - Warriup 57 km E. of .Albany. 74A16b Green Range, 70 km E. of Albany. Time of Planting (4) Seeding Rates (4) Varieties (4) Fertiliser.


Summary Of Experimental Work 1974, G Walton Jan 1974

Summary Of Experimental Work 1974, G Walton

Experimental Summaries - Plant Research

Lupinus albus cv WB2: Maximum yield response to 36 plants/m2 at Avondale (1973 and 1974) and Mt Barker Research Station in 1973 (achieved with 180 to 200 kg/ha seed rate), Maximum yield response to 48 plants/m2 at Chapman 1973 and 1974 and at Eradu 1974 (achieved with 220 tG 240 kg/ha). Very good yield results: Season - site Avondale 1973-3300, 1974-2250. kg/ha Chapman 1973-2800, 1974-2400. Mt Barker 1973-1900. 74A2 - Rates Of seeding for L, albus cv WB2. 74A21 - Rates of super on two lupin varieties. 74BR1 - Pasture regeneration after lupin survey. 74C4 - Rates of seeding L. …


Prostaglandins From Plexaura Homomalla: Ecology, Utilization And Conservation Of A Major Medical Marine Resource. A Symposium, Frederick M. Bayer, Alfred J. Weinheimer Jan 1974

Prostaglandins From Plexaura Homomalla: Ecology, Utilization And Conservation Of A Major Medical Marine Resource. A Symposium, Frederick M. Bayer, Alfred J. Weinheimer

Studies in Tropical Oceanography

No abstract provided.