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An Examination Of Prostaglandins As Causative Agents In Pine Needle (Pinus Ponderosa) Abortion, Daniel P. Shue Jan 1983

An Examination Of Prostaglandins As Causative Agents In Pine Needle (Pinus Ponderosa) Abortion, Daniel P. Shue

Electronic Theses and Dissertations

Cow and calf losses due to pine needle abortion in cattle grazing foothill ranges of ponderosa pine (Pinus ponderosa) continue to cause managerial and economic problems for ranchers in South Dakota, Colorado, Idaho, California, Montana and many areas throughout Canada. Because of its overall economic significance, investigators have been attempting to isolate and characterize causative agents of pine needle abortion. To date, a large number of pine needle constituents have been shown to possess abortifacient capabilities. In addition to actual pine needles, it appears that several other undefined factors may be associated with, and (or) predispose animals to, pine needle …


Effects And Interactions Of Nitrogen And Soil Moisture Status Under A High Yield Irrigated Corn Environment, Dwayne L. Beck Jan 1983

Effects And Interactions Of Nitrogen And Soil Moisture Status Under A High Yield Irrigated Corn Environment, Dwayne L. Beck

Electronic Theses and Dissertations

A two-part study was conducted during the 1979 and 1980 growing seasons on irrigated lands adjoining the Missouri River in central South Dakota. Empirical [sic] models were developed to describe the response of irrigated corn (Zea mays L.) to soil water status and nitrogen fertilization at a location recently developed for sprinkler irrigation. Nitrogen fertilizer rates of 0, 100, 200, and 400 kg of N/ha were used under water treatments consisting of a 2.5 cm irrigation when soil water matric potential at a depth of 40 cm decreased to -35, -50, and -75 kPa. Yield differences due to soil water …


Spawning The Grass Carp Female X Bighead Carp Male, Mike Freeze, Scott Henderson Jan 1983

Spawning The Grass Carp Female X Bighead Carp Male, Mike Freeze, Scott Henderson

Journal of the Arkansas Academy of Science

Methods and procedures for artificially spawning the female grass carp (Ctenopharyngodon idella) X male bighead carp (Aristichthys nobilis) are presented. Broodstock selection and treatment, hormone injections, ovulation, fertilization, hatching techniques and stocking rates are discussed. This paper outlines the procedures necessary to successfully produce hybrid grass carp


Observaciones Sobre La Biología De Phyllomedusa Iheringi Boulenger, 1885, (Anura, Hylidae), Rafael O. De Sá, Annelise Gerhau Jan 1983

Observaciones Sobre La Biología De Phyllomedusa Iheringi Boulenger, 1885, (Anura, Hylidae), Rafael O. De Sá, Annelise Gerhau

Biology Faculty Publications

RESUMEN:

Se presentan las características que permiten diferenciar las larvas de Phyllomedusa iheringi de las de otros anuros que habitan en nuestro territorio, junto con algunas observaciones sobre la biología de esta especie poco conocida en el Uruguay.

SUMMARY:

The characteristics that differentiate the larvae of Phyllomedusa iheringi from other anurans that live in Uruguay are presented here. Some observations on the biology of this species are also recorded.


The Relationship Between Whole Brain Catecholamine Depletion In Carassius Auratus And The Exposure To Inescapable Shock In A Learned Helplessness Paradigm, Roderick J. Misunis Jan 1983

The Relationship Between Whole Brain Catecholamine Depletion In Carassius Auratus And The Exposure To Inescapable Shock In A Learned Helplessness Paradigm, Roderick J. Misunis

Masters Theses

Learned helplessness is a psychological concept that describes the subsequent escape-avoidance behavior of experimental subjects who are exposed to uncontrollable stressors. Subjects after treatment are unable to respond in situations where escape is possible. Two major theorists, Seligman and Weiss, have proposed explanations concerning the phenomena. Seligman feels that the subject is unable to respond due to the fact that the exposure to an uncontrollable stressor has caused him to learn to be "helpless". Weiss feels that the inability to respond can best be described by alterations in the subject's brain neurochemistry, specifically the neurotransmitter norepinephrine. This paper is an …


The Effect Of Repeated Spermiation On Sperm Density In The American Toad (Bufo Americanus), Michael A. Kriz Jan 1983

The Effect Of Repeated Spermiation On Sperm Density In The American Toad (Bufo Americanus), Michael A. Kriz

Masters Theses

Bufo americanus (American toad) responds to LH-RF injections by releasing sperm into the cloaca. An ANOVA test (repeated measures) was used to determine that spermiation number and body size but not frequency of injection affected sperm density. The affects of body size on sperm density were that large toads produced the highest sperm densities, followed by the medium and then the small toads. Sperm density decreased with repeated spermiations which could correlate with the explosive breeding pattern of the American toad.


Factors Influencing Reforestation Of Surface Mined Lands In Southern Illinois, Jill R. Medland Jan 1983

Factors Influencing Reforestation Of Surface Mined Lands In Southern Illinois, Jill R. Medland

Masters Theses

Studies of surface coal mined lands have focused primarily on older lands mined prior to the enactment of reclamation legislation. Current laws will require extensive grading, soil replacement and revegetation. In order to more effectively reforest these lands, I have evaluated sites planted to woody species during the past decade.

The vegetational characteristics, as well as both avaian and small mammal populations of several reclaimed surface mined areas, differing in age and reclamation procedures, were compared. Success of planted trees ranged from 50 to 91% and survival varied with the species planted. There was no relationship between tree survival and …


Some Effects Of Simulated Acid Rain On Cool Season Turfgrasses, Robert C. Morrow Jan 1983

Some Effects Of Simulated Acid Rain On Cool Season Turfgrasses, Robert C. Morrow

Masters Theses

Six varieties of cool season turfgrasses were exposed to simulated acid rainfall with treatments consisting of a sulfuric acid solution, a nitric acid solution, and a 50-50 mixture of both. Each solution was used to make "acid rain" of pHs 3.0, 2.5, 2.0, and 1.5.

Height measurements showed decreases in growth throughout the experiment for all treatments except the nitric and 50-50 acid treatments at pHs of 2.0 and 1.5, which maintain fairly constant growth. Analysis of nitrate, phosphorous, and potassium levels in the soil indicated heavy leaching of the nitrates and potassium from most soil samples, which probably account …


Autumn Olive Reproduction In Three Illinois State Parks, James Daniel Nestleroad Jan 1983

Autumn Olive Reproduction In Three Illinois State Parks, James Daniel Nestleroad

Masters Theses

No abstract provided.


Natural Variation And Regulation Of Floral Ultraviolet Absorption In Coreopsis And Bidens, Ron Scogin Jan 1983

Natural Variation And Regulation Of Floral Ultraviolet Absorption In Coreopsis And Bidens, Ron Scogin

Aliso: A Journal of Systematic and Floristic Botany

No abstract provided.


Use Of Hydroelectric Dams To Control Evaporation And Salinity In The Colorado River System, Larry J. Paulson Jan 1983

Use Of Hydroelectric Dams To Control Evaporation And Salinity In The Colorado River System, Larry J. Paulson

Publications (WR)

The main stem reservoirs on the Colorado River comprise one of the largest and most heavily used freshwater bodies in the nation. These reservoirs (Lake Powell, Lake Mead, Lake Mohave and Lake Havasu) can store up to 53,590,400 acre-feet of water at their maximum capacities. Nonetheless, local water shortages still exist in some areas of the Colorado River Basin. There is also concern that salt concentrations are approaching levels that could severely affect municipal and agricultural uses. Water shortages will become even more acute as demands for water increase with continued urban and agricultural development in the basin. Water conservation …


Historical Patterns Of Phytoplankton Productivity In Lake Mead, Richard T. Prentki, Larry J. Paulson Jan 1983

Historical Patterns Of Phytoplankton Productivity In Lake Mead, Richard T. Prentki, Larry J. Paulson

Publications (WR)

Lake Mead was impounded in 1935 by the construction of Hoover Dam. The Colorado River was unregulated prior to then and therefore was subjected to extreme variations in flows and suspended sediment loads. Hoover Dam stabilized flows and reduced suspended sediment loads downstream, but Lake Mead still received silt-laden inflows from the upper Colorado River Basin. The Colorado River contributed 97% of the suspended sediment inputs to Lake Mead, and up to 140 x 1O6 metric tons (t) entered the reservoir in years of high runoff. Most of the sediments were deposited in the river channel and formed an …


The Influence Of Lake Powell On The Suspended Sediment-Phosphorus Dynamics Of The Colorado River Inflow To Lake Mead, T. D. Evans, Larry J. Paulson Jan 1983

The Influence Of Lake Powell On The Suspended Sediment-Phosphorus Dynamics Of The Colorado River Inflow To Lake Mead, T. D. Evans, Larry J. Paulson

Publications (WR)

The Colorado River has been successively modified by the construction of several reservoirs, beginning in 1935 with the formation of Lake Mead by Hoover Dam. These reservoirs are located in a chain, and each one has an influence on the nutrient dynamics and productivity of the river and downstream reservoir. Lake Mead derives 98% of its annual inflow from the Colorado River. Historically, the Colorado River inflow was unregulated into Lake Mead. Regulation occurred in 1963, when Lake Powell was impounded by the construction of Glen Canyon Dam, approximately 450 km upstream. The formation of Lake Powell drastically altered the …


Enteric Infections In Stockton, California : With Special Reference To The Genus Campylobacter, Tom Edward Hathorn Jan 1983

Enteric Infections In Stockton, California : With Special Reference To The Genus Campylobacter, Tom Edward Hathorn

University of the Pacific Theses and Dissertations

During the last two or three years, the three largest hospitals in Stockton (St. Joseph’s, Dameron and San Joaquin General Hospitals) have modified their procedures to include the search for Campylobacter. On the other hand, the incidence of Yersinia in California is unknown, as most clinical laboratories do not specifically culture for it. There have been only a few reports of Yersinia in this state (personal communication of Dennis Ferrero, Director of the San Joaquin County Public Health Laboratory). This study has a threefold purpose: to investigate the incidences of Campylobacter and Yersinia, especially in relation to the incidence of …


Ultrafiltration Of Skim Milk Prior To Cottage Cheese Making, Izhar H. Athar Jan 1983

Ultrafiltration Of Skim Milk Prior To Cottage Cheese Making, Izhar H. Athar

Electronic Theses and Dissertations

Cottage cheese has the largest sales volume potential of all cultured dairy products in the United States today. Moreover, it can be a highly profitable product if proper control is exercised during its manufacturing (46). Commercial production of cottage cheese utilizes a significant portion of the total fluid milk produced in the U. S.A. After the 1955's, yearly per capita consumption of cottage cheese increased from 1. 7 7 kg (3.9 lb) to a high of 2. 45 kg (5.4 lb) in 1972 (67) . Consumer demand for lower fat dairy products gradually increased, which put more pricing emphasis on …


Some Effects Of Naturally Occurring Amygdalin On Female C3h/Hej Mice, Gareth Eli Shemesh Jan 1983

Some Effects Of Naturally Occurring Amygdalin On Female C3h/Hej Mice, Gareth Eli Shemesh

Master's Theses

No abstract provided.


Eucalypts: Energy Tree Of The Future?, Richard B. Pearce Jan 1983

Eucalypts: Energy Tree Of The Future?, Richard B. Pearce

Richard B. Pearce Archival Documents

This article by Richard B. Pearce was published in the January 1983 issue of American Forest. It examines the potential of eucalyptus species as a renewable energy resource. Discusses research on the rapid growth and cultivation of eucalyptus trees and their increasing interest to American foresters for energy production.


The Cousteau Log Centering On Marine Animals For Elementary School Children, Annie Suffron Jan 1983

The Cousteau Log Centering On Marine Animals For Elementary School Children, Annie Suffron

All Graduate Projects

"Centering on Marine Animals for Elementary School Children" was a multi-curricular learning center design in four parts. It consisted of an introduction on Bubbles the Whale, including a picture, a puppet, a song, a Sea Script, and task cards. Following the introduction were three units on Sea Monsters of the World, the Migration of the Grey Whale, and the Ecology of the Southern Sea Otter. Each unit contained a picture of the sea animal, a puppet, a song, a Sea Script, a Quiz, map(s), and task cards.


Rumen Microbial Protein Synthesis In Cows Fed Dried Whey, Paul M. Windschitl Jan 1983

Rumen Microbial Protein Synthesis In Cows Fed Dried Whey, Paul M. Windschitl

Electronic Theses and Dissertations

Two rumen fistulated Holstein cows, weighing approximately 550 kg, were used in a switchback design experiment to evaluate the effects of consuming large amounts (38% of total ration dry matter) of dried whey on rumen microbial protein synthesis. Cows were fed total mixed rations consisting of (dry matter basis) 45% corn silage, 10% alfalfa hay, and 45% concentrate mix. The concentrate mix was primarily corn and soybean meal (control) or 85% dried whole whey. Dry matter intakes averaged 16.4 and 15.3 kg/day for control and whey diets. Concentrations of bacteria and protozoa in rumen contents were estimated using diaminopimelic acid …


A Biosystematic Study Of The Polemonium Reptans L. Complex In The Eastern United States Including P. Reptans L. Var. Reptans, P. Reptans L. Var. Villosum Braun And Related Taxa (Polemoniaceae), Bill Lucas Jan 1983

A Biosystematic Study Of The Polemonium Reptans L. Complex In The Eastern United States Including P. Reptans L. Var. Reptans, P. Reptans L. Var. Villosum Braun And Related Taxa (Polemoniaceae), Bill Lucas

Theses, Dissertations and Capstones

The taxonanic relationship of Polemoniun reptans L. var. reptans and P. reptans L. var. villosum Braun (Polemoniaceae) is examined in this studly. The former taxon occurs throughout most of the eastern deciduous forest while the latter is rare and limited to southern Ohio and northcentral Kentucky. The natural coherence of the species has provided a bimodal frequency distribution which displays clustering of the two varieties at opposite ends of a continuum. Significant differences were obtained using the BMDP7M multivariate analysis (0.05 level of significance) based on morphometric information gathered from herbarium specimens throughout the midwest and eastern states, between var. …


Stomatal Density In Leaves Of Various Xerophytes: A Preliminary Study, David W. Strobel, Marshall D. Sundberg Jan 1983

Stomatal Density In Leaves Of Various Xerophytes: A Preliminary Study, David W. Strobel, Marshall D. Sundberg

Journal of the Minnesota Academy of Science

Recent general botany and plant anatomy textbooks state that stomatal density of xerophytic leaves is higher than that found in leaves of mesophytes. In contrast, previous textbooks indicate that stomatal density in xerophyte leaves is reduced. The purpose of this study is to examine the leaves of succulent and non-succulent xerophytes to determine if opposite trends in stomatal density correlate with the xeromorphic strategy employed. The species examined were the succulents Crassula argentea, Kalanchoe blossfeldiana, K. diagremontiana, K. tubiflorum, and the non-succulents Nerium oleander, Ammophila breviligulata, and Ficus elastica. Stomatal densities of succulents were determined directly from epidermal peels. Stomatal …


Mate And Nest-Site Fidelity Among Tree Swallows In Central Minnesota, Carol Fiedler, Alfred Grewe Jan 1983

Mate And Nest-Site Fidelity Among Tree Swallows In Central Minnesota, Carol Fiedler, Alfred Grewe

Journal of the Minnesota Academy of Science

Movement of tree swallows (lridoprocne bicolor) between successive breeding sites and pair bond formation was analyzed from data collected between 1965 and 1978 in central Minnesota. A lasting pair bond did not seem to exist between breeding pairs. The majority of the breeding pairs were found to separate after one year. Those that did remate usually did so in the same or an adjacent nest box. Age and reproductive success did not appear to affect whether a pair remated or divorced. Movement of the male and female the year following their mating did seem to be a factor. Males tended …


Amphipods Of The Family Ampeliscidae (Gammaridea). I. Ampelisca Bicarinata, A New Species Of Amphipod From The Gulf Of Mexico, Gary D. Goeke, Richard W. Heard Jan 1983

Amphipods Of The Family Ampeliscidae (Gammaridea). I. Ampelisca Bicarinata, A New Species Of Amphipod From The Gulf Of Mexico, Gary D. Goeke, Richard W. Heard

Gulf and Caribbean Research

A new species of the benthic amphipod genus Ampelisca Kroyer, is described and illustrated. Previous records of the Pacific species Ampelisca cristoides Barnard, 1954, from the western North Atlantic are now assignable to the proposed new species, Ampelisca bicarinata. These two closely related sibling species are compared and their specific differences enumerated.


The Role Of Lh Pulses On In Vitro Follicular Development In The Metestrous Rat Ovary, Shirley Jane Luttmer Jan 1983

The Role Of Lh Pulses On In Vitro Follicular Development In The Metestrous Rat Ovary, Shirley Jane Luttmer

Master's Theses

No abstract provided.


An Ecological Succession Model Applied To Environmental Management, Diane Rosenberg Jan 1983

An Ecological Succession Model Applied To Environmental Management, Diane Rosenberg

Master's Theses

No abstract provided.


Prevalence Of Baylisascaris Procyonis In Northern Illinois And Larval Migration In The Mongolian Gerbil (Meriones Unguiculatus), Diane Mary Sudduth Jan 1983

Prevalence Of Baylisascaris Procyonis In Northern Illinois And Larval Migration In The Mongolian Gerbil (Meriones Unguiculatus), Diane Mary Sudduth

Master's Theses

No abstract provided.


Distribution Of The Marsh Periwinkle Littorina Irrorata (Say) In A Virginia Salt Marsh, R. Wyle Crist, William C. Banta Jan 1983

Distribution Of The Marsh Periwinkle Littorina Irrorata (Say) In A Virginia Salt Marsh, R. Wyle Crist, William C. Banta

Gulf and Caribbean Research

Littorina irrorata varies over its geographic range in maximum size, preferred elevations relative to tidal datum planes, and in the type of vegetation it inhabits. On Wallops Island, Virginia, postlarvae of Littorina irrorata with shell lengths < 5 mm long live almost exclusively in dead, curled-up leaves of Spartina alterniflora at elevations near mean tide level, below elevations occupied by larger conspecifics. Snails longer than 5 mm in length increase in average size with decreasing elevation. This distribution is opposite to that found by Hamilton (1978) in a marsh in Florida. No difference was found in our study area in growth rate of marked snails at two different elevations, so the size-elevation …


Effects Of Saltwater Intrusion From The Inner Harbor Navigation Canal On The Benthos Of Lake Pontchartrain, Louisiana, Jane A. Junot, Michael A. Poirrier, Thomas M. Soniat Jan 1983

Effects Of Saltwater Intrusion From The Inner Harbor Navigation Canal On The Benthos Of Lake Pontchartrain, Louisiana, Jane A. Junot, Michael A. Poirrier, Thomas M. Soniat

Gulf and Caribbean Research

A study of the benthos of southern Lake Pontchartrain, Louisiana, was conducted from July 1976 to July 1978. Seven offshore stations and three stations in the New Orleans Marina complex were sampled seasonally. Offshore stations formed a transect from the Lake Pontchartrain Causeway to the Inner Harbor Navigation Canal (I.H.N.C.). A west to east gradient of increasing salinity and salinity stratification was evident.

Faunal differences among stations were assessed using indices of diversity, biological dominance, pollution, and station homogeneity. The fauna of the marina stations had a low species diversity and was dominated by annelids, indicative of a stressed environment. …


Community Structure Of Diatoms Epiphytic On Pneumatophores Of The Black Mangrove, Avicennia Germinans, In A Louisiana Salt Marsh, Robert S. Maples Jan 1983

Community Structure Of Diatoms Epiphytic On Pneumatophores Of The Black Mangrove, Avicennia Germinans, In A Louisiana Salt Marsh, Robert S. Maples

Gulf and Caribbean Research

The taxonomy, diversity, and similarity of diatom assemblages epiphytic on pneumatophores of black mangrove, Avicennia germinans (L.) L., in southeastern Louisiana were investigated. A total of 109 taxa representing 27 genera were identified in samples from five sites. The most abundant taxa were Nitzschia brittonii Hagelstein, Nitz. frustulum (Kutz.) Grun., Navicula diserta Hust., Denticula subtilis Grun., and Amphora tenuissima Hust. Comparisons with previous studies indicate that the diatom flora epiphytic on A. germinans in this study is much more characteristic of temperate salt marshes than of subtropical mangrove communities.


Tanaidacea (Crustacea: Peracardia) Of The Gulf Of Mexico. Iii. On The Occurrence Of Teleotanais Gerlachi Lang, 1956 (Nototanaidae) In The Eastern Gulf, Jurgen Sieg, Richard W. Heard Jan 1983

Tanaidacea (Crustacea: Peracardia) Of The Gulf Of Mexico. Iii. On The Occurrence Of Teleotanais Gerlachi Lang, 1956 (Nototanaidae) In The Eastern Gulf, Jurgen Sieg, Richard W. Heard

Gulf and Caribbean Research

Teleotanais gerlachi Lang, 1956, a euryhaline member of the family Nototanaidae, known from Brazil and El Salvador, is reported from the eastern Gulf of Mexico (west coast of Florida) and the west coast of Africa (Nigeria). The species is diagnosed and illustrated. Differences between Teleotanais and the superficially similar genus Paratanais (Pantanaidae) are briefly compared and discussed.