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Articles 20101 - 20130 of 20603
Full-Text Articles in Entire DC Network
Spatial Distribution & Temporal Occurrence Of Rotifers In The Main Pool & Tailwater Of Barren Lake, Kentucky, David Abel
Spatial Distribution & Temporal Occurrence Of Rotifers In The Main Pool & Tailwater Of Barren Lake, Kentucky, David Abel
Biology Graduate Theses
A study of the spatial distribution and temporal occurrence and diversity of rotifers in relation to certain chemicophysical parameters was conducted in Barren Lake, Kentucky, a flood control lake, from January, 1970, through January, 1970. Paired samples were collected from six depths in the main pool area of the reservoir and from an automatic plankton sampler installed in the tailwater area where, from April through September, the effluent was derived from the upper 3 m of the pool . Diel studies were conducted in April, July, 1970, and January, 1971.
Barren Lake began to stratify in late April, was completely …
The Effect Of Adrenalectomy And Corticosterone Therapy On The Incidence Of Gastric Ulcers In The Rat, Steven Paul Lorton
The Effect Of Adrenalectomy And Corticosterone Therapy On The Incidence Of Gastric Ulcers In The Rat, Steven Paul Lorton
Historical Dissertations & Theses
It was the purpose of this investigation to study the effects of adrenalectomy on gastric ulceration and to attempt to clarify the mechanism of ulcer formation in the rat. The effect of corticosterone therapy on the incidence of ulcers in nonstressed and stressed, adrenalectomized rats was studied to determine whether glucocorticoids play a role in the formation of gastric ulcers.
Inorganic Mercury Uptake And Mercury Tolerance Demonstrated By Several Species Of Algae, Daniel S. Filip
Inorganic Mercury Uptake And Mercury Tolerance Demonstrated By Several Species Of Algae, Daniel S. Filip
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The inhibition by low concentrations of inorganic mercury has been established for several species of freshwater algae, and a method has been developed to determine mercury levels in algal cells, having good precision at levels as low as one hundred parts per billion.
Rapid sorption of inorganic mercury by glassware was minimized by using heavy algal cultures and short term incubations. The rates and extent of mercury uptake by three species of freshwater green algae were delineated under laboratory conditions. Replicate mercury containing cultures yielded slightly different mercury concentrations upon analysis due to analytical errors and glass sorption. Therefore, percent …
Radioimmuno Detection Of Virus, John Carlos Perez
Radioimmuno Detection Of Virus, John Carlos Perez
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The commonly used techniques for viral detection are tedious, time consuming and in many cases inadequate. As a consequence, a rapid, sensitive radioimmunoassay has been developed for detecting viruses. Reovirus is reacted with homologous 125I labeled antibody after which the antigen-antibody complexes are separated from unreacted labeled antibody by density gradient ultracentrifugation. After centrifugation, the density gradient is fractionated and the radioactivity counted in a liquid scintillation spectrometer.
The amount of activity in the lower fractions of the density gradient is directly proportional to the virus concentration. The radioimmunoassay developed has several advantages over other viral assay procedures; the …
An Analysis Of Flock Organization In Black-Capped Chickadees, John Ivan Mosher
An Analysis Of Flock Organization In Black-Capped Chickadees, John Ivan Mosher
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
An analysis was made of individual behavior and flock organization among 33 color-banded Black-capped Chickadees (Parus atricapillus) on a woodland tract in wester New York State, from December 1967 to June 1970. Also, three of these flocks were confined at various periods for an average aviary tenure of 26 days. From these observations I concluded that the hierarchy and interindividual relationship of a flock remain as observed in the field; testosterone propionate causes an increase in injected subordinate bird's activity; but did not effect a change in its rank.
From the observations in the aviary, it was found …
Nitrification Potential In Arid Western Soils, Hasumati R. Patel
Nitrification Potential In Arid Western Soils, Hasumati R. Patel
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Nitrification rates were determined by perfusion method in Southern Curlew Valley (Utah) soils from 0 to 1.3 meter profiles as a function of seasons. Ammonification rates were determined at various moisture contents and seasonal variations of ammonium concentration in the same soils were estimated.
Rate of nitrification was higher in warm showery periods (May and June) than in colder periods (September, October and November). In the top 3 cm layer, nitrifying activity was several fold higher than in the rest of the profile. Cultivation increased the nitrification rate.
Considerable ammonium fixation by soil particles, volatilazation of ammonia and nitrite accumulation …
Effects Of Several Solutes And Water Stress On Succinic Dehydrogenase Activity, Rex Alton Richards
Effects Of Several Solutes And Water Stress On Succinic Dehydrogenase Activity, Rex Alton Richards
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The influence of the concentration of several solutes on the activity of succinic dehydrogenases from acetone powders of several species was studied spectrophotometrically. The plants used were: Cauliflower (Brassica oleracea var. botrytis, L.) sugarbeet (Beta vugaris, L.) sunflower (Helianthus annus, L.), Halogeton glomeratus (M. Bieb) C.A. Mey., and Samphire (Salicornia rubra, A. Nels.). Sodium chloride, potassium chloride, mannitol, sucrose, glycerol, glucose, and Hoagland's solution, at increasing concentrations, were used.
Decreased (more negative) osmotic potential produced by sodium chloride, potassium chloride, and Hoagland's solution resulted in a slight increase in enzyme activity at low …
The Effects Of Age And Induction On Cockroach Mixed Function Oxidase Activity And Cell Morphology, Richard L. Turnquist
The Effects Of Age And Induction On Cockroach Mixed Function Oxidase Activity And Cell Morphology, Richard L. Turnquist
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Female American cockroaches showed definite age-dependent changes in levels of activity of the microsomal mixed function oxidase chain. Cytochrome P-450 levels, EPN-detoxication, and p-nitroanisole O-demethylation activities were very low in young adult insects but increased steadily reaching a peak at about 100 days in fat body and at about 90 days in midgut and hindgut. The activities then declined rapidly reaching levels of young insects at about 130 to 140 days of age. NADPH-NT-reductase activity was high in young insects and declined during the first few weeks of adult life. This activity too showed a peak at about …
Cynipid Gall Anatomy And Distribution Of The Causal Organism, David E. Murray
Cynipid Gall Anatomy And Distribution Of The Causal Organism, David E. Murray
Morehead State Theses and Dissertations
A thesis presented to the faculty of the School of Sciences and Mathematics at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science in Biology by David E. Murray on April 28, 1972.
Some Aspects Of The Ecology Of Perognathus Flavus, Dipodomys Ordi, And Dipodomys Merriami, L. Gwen Britt
Some Aspects Of The Ecology Of Perognathus Flavus, Dipodomys Ordi, And Dipodomys Merriami, L. Gwen Britt
Biology ETDs
A total of 3331 animals was trapped from August 1966 to September 1969. Three hundred and eighty-five marked P. flavus were captured 2058 times and 173 marked Dipodomys were captured 950 times. The mean population estimate for a year of study was 5.6 Dipodomys (two species) and 13.4 P. flavus per acre. There was an estimated biomass per acre of 97.8g for P. flavus and 262g for Dipodomys. Perognathu and Dipodomys hewed similar persistence curves with about half of the animals persisting for only 2 months. About 75% of the animals were gone after 6 months with a few persisting …
Protein Catabolism And Urea Utilization In Water-Deprived And Fasted Ground Squirrels And Rats, Gerald L. Rigler
Protein Catabolism And Urea Utilization In Water-Deprived And Fasted Ground Squirrels And Rats, Gerald L. Rigler
Biology ETDs
The objective of this study was to examine a specific metabolic adaptation, namely, the extent to which protein catabolism was changed in long-term water-deprived and starved Spennophilus lateralis, S. spilosoma, and laboratory rats. It was thought from previous studies that the relative amount of protein and fat catabolism affects water balance and thus determines how long an animal will survive water deprivation. Hibernators may possess unique metabolic flexibility in adapting to water deprivation as they apparently adapt to dehydration when they are hibernating.
In the first series of experiments animals· were water deprived for 6 days at 2 seasons and …
The Effect Of Hibernation On Memory In Spermophilus Lateralis, Mary Colleen Mcnamara
The Effect Of Hibernation On Memory In Spermophilus Lateralis, Mary Colleen Mcnamara
Biology ETDs
Spermophilus lateralis, were trained to solve a black-white discrimination task in order to escape from a water filled tank. Following the attainment of criterion, the ground squirrels were trained on the reversal task of the original discrimination problem. Twenty-four hours after reaching criterion on the reversal training, all subjects were placed in a hibernaculum at 7-10 C for a period of 11 days. The animals were returned to the laboratory after the 11-day
cold exposure period, and 24 hr later were tested for retention of the learned behavior. The animals were returned to the hibernaculum for an additional 11 days …
Induced Changes In The Rates Of Uridine-3H Uptake And Incorporation During The G1 And S Periods Of Synchronized Chinese Hamster Cells, Peter J. Stambrook, Jesse E. Sisken
Induced Changes In The Rates Of Uridine-3H Uptake And Incorporation During The G1 And S Periods Of Synchronized Chinese Hamster Cells, Peter J. Stambrook, Jesse E. Sisken
Biology Faculty Publications
The rates of uridine-5-3H incorporation into RNA and the rates of uridine uptake into the acid-soluble pool during the cell cycle of V79 Chinese hamster cells were examined. Cells cultured on Eagle's minimal essential medium supplemented with fetal calf serum, lactalbumin hydrolysate, glutamine, and trypsin displayed rates of incorporation and uptake which increased only slightly during G1 and accelerated sharply as DNA synthesis commenced. In contrast, cells cultured on minimal essential medium supplemented only with calf serum exhibited rates of incorporation and uptake which increased linearly through both G1 and S. The transition from one pattern …
Effects Of Hippocampal Lesions On Performance In A Shock Escape Task, George L. Reuthebuck
Effects Of Hippocampal Lesions On Performance In A Shock Escape Task, George L. Reuthebuck
Morehead State Theses and Dissertations
Submitted in partial fulfillment of the requirements for the degree of Master of Arts in Psychology in the Graduate School of Morehead State University by George L. Reuthebuck on January 21, 1972.
Biology Of Chrysemys Picta Bellii In Southwestern Minnesota, Carl H. Ernst, Evelyn M. Ernst
Biology Of Chrysemys Picta Bellii In Southwestern Minnesota, Carl H. Ernst, Evelyn M. Ernst
Journal of the Minnesota Academy of Science
The turtle, Chrysemys picta belIii, was studied in southwestern Minnesota. The taxonomic characteristics are analyzed. The turtles are diurnal and have an annual activity period extending from mid-May to October. Activity and feeding are controlled by water temperature. The population dynamics are discussed. Growth is rapid early in life but slows after maturity. Growth is compared with that of other subspecies of C. picta. Habitat preferences, predation, parasites, algal relationships and shell abnormalities are discussed.
Food Habits And Life History Of Stoneflies Of The Cle Elum River, Washington, Thomas Edward Swapp
Food Habits And Life History Of Stoneflies Of The Cle Elum River, Washington, Thomas Edward Swapp
All Master's Theses
This paper presents an evaluation of the food habits of 20 species of stoneflies (Plecoptera) as determined by guy analysis. Life history data, principally adult emergence periods and seasonal distribution of naiads, are presented for 38 species. Finally, an evaluation is made of the stoneflies' diet composition and the seasonal availability of potential food materials.
The Effects Of Estrogen On Ionized Calcium In Ovariectomized Calciphylactic Rats, Edward Luverne Hatcher
The Effects Of Estrogen On Ionized Calcium In Ovariectomized Calciphylactic Rats, Edward Luverne Hatcher
Dissertations and Theses @ UNI
This research was an attempt to discover the relationship between estrogen treatment and the serum calcium levels in ovariectomized rats. An attempt was also made to study the possible effects of estrogen on calcium deposition during the calcification process by utilizing the calciphylaxis phenomena as a potential biological model. Concentrations of ionized and total calcium in the serum of ovariectomized rats were measured utilizing a calcium selective electrode system and atomic absorption spectroscopy procedures respectively. This was done following 3- and 6-day treatments with estrogen (0.1 µg). The same analysis was used in the calciphylactic treatment procedures both with and …
Development Of A Flameless Atomic Absorption Assay For Mercury In Biological Materials And Levels Of Mercury Detected In Striped Bass (Roccus Saxatilis) Collected In The San Joaquin Delta, Patrick Glenn Burch
Development Of A Flameless Atomic Absorption Assay For Mercury In Biological Materials And Levels Of Mercury Detected In Striped Bass (Roccus Saxatilis) Collected In The San Joaquin Delta, Patrick Glenn Burch
University of the Pacific Theses and Dissertations
The method for the determination of total mercury in biological material described in this paper comprises a destruction of organic matter by wet digestion, a reduction of the mercury by stannous sulfate, and circulation of the displaced mercury vapor in a closed system directly connected with an atomic absorption spectrophotometer Seven tissues from ten samples of locally obtained Roccus saxatilis (striped bass) were analyzed, and a three-fold elevation of mercury levels in the liver over the levels in the filet noted. See Table XIX for a comparison of the high, low, and average values for each tissue.
Facilitated Diffusion In Rabbit Erythrocytes, Arthur Hing-Cheung Chui
Facilitated Diffusion In Rabbit Erythrocytes, Arthur Hing-Cheung Chui
University of the Pacific Theses and Dissertations
The present kinetic study of the permeability of rabbit erythrocytes has established that carrier systems are involved in the penetration of certain non-electrolytes. Saturation, competitive inhibition, and butanol inhibition kinetics were used to demonstrate the presence of carrier systems and the values of half-saturation constants (ø) were determined for the following water soluble non-electrolytes: glycerol, ethylene glycol, urea, and thiourea.
These non-electrolytes are commonly used in permeability studies because they are relatively non-toxic and their small sizes allow penetration of the erythrocyte membrane within a reasonable length of time.
The Larval Morphology Of Three Species Of Pagurus (Decapoda, Anomura) From California, William R. Hall
The Larval Morphology Of Three Species Of Pagurus (Decapoda, Anomura) From California, William R. Hall
University of the Pacific Theses and Dissertations
This study is concerned with description of larval stages of Pagurus granosimanus, P. hemphilli and P. hirsutiusculus. All three are found intertidally in Northern California. Descriptions are based on laboratory raised zoea and glaucothoe.
The Formation And Constriction Of The Trapping Rings In The Nematophagous Fungus Dactylaria Brochopaga Dreschler, Walter Thomas Rudek
The Formation And Constriction Of The Trapping Rings In The Nematophagous Fungus Dactylaria Brochopaga Dreschler, Walter Thomas Rudek
Master's Theses
No abstract provided.
Pharmacological Effects Of A Bufadienolide Isolated From The Toad Bufo Boreas Halophilus, Roy Gordon Knickelbein
Pharmacological Effects Of A Bufadienolide Isolated From The Toad Bufo Boreas Halophilus, Roy Gordon Knickelbein
University of the Pacific Theses and Dissertations
For centuries, men have known that the skin of toads and other amphibians possess pharmacologically active compounds (Abel and Nacht,1911;Chen and Jensen,1929;Chen and Kovarikova,1967).All amphibians produce toxins in glands scattered over the skin .Many anuran amphibians have parotoid glands located on the lateral ,anterior ldorsal surface which are apparently specialized for the secretion of large quantities of toxin. W'eiss(1899) and Muhse(1909) describe the histology of these glands.
A Study Of Lungs In Rana Catesbeiana Tadpoles, Ross Miles Hart
A Study Of Lungs In Rana Catesbeiana Tadpoles, Ross Miles Hart
University of the Pacific Theses and Dissertations
The first quantitative studies of pulmonary and cutaneous respiration in the amphibians were made on Rana esculenta and Rana temporaria by Krogh (1904). He inserted a cannula connected to an air pump into the trachea and analyzed separately the air forced through the lungs by the pump and the air surrounding the frog. He was able to show that in R. temporaria the lungs and skin are both important in respiratory exchange but in somewhat different ways. Oxygen enters through the lungs whereas carbon dioxide is excreted through the skin. Oxygen intake through the skin is determined solely by physical …
Simple And Facilitated Diffusion In Rat Erythrocytes, Stephen Rudolph Cainelli
Simple And Facilitated Diffusion In Rat Erythrocytes, Stephen Rudolph Cainelli
University of the Pacific Theses and Dissertations
Early studies of the permeability of the animal cell membrane were difficult to compare, because of the variety of cell types involved. In the late nineteenth century, workers chose to use erythrocytes due to their advantages over using a variety of cell types. With erythrocytes a comparison could be developed between strictly homologous cells of many different species. Erythrocytes are easily obtainable and mature cells are separate from all other cells of the body as well as from each other. Of even greater importance is the fact that the mature erythrocyte’s major function is the uptake of the greatest possible …
Biosystematic Evidence For Hybridization Between Lysimachia Quadriflora Sims And Lysimachia Hybrida Michaux (Primulaceae), Michael Owen Dillon
Biosystematic Evidence For Hybridization Between Lysimachia Quadriflora Sims And Lysimachia Hybrida Michaux (Primulaceae), Michael Owen Dillon
Dissertations and Theses @ UNI
Putative hybrids between Lysimachia guadriflora and L. hybrida were discovered in a marsh in Dickinson County in northwest Iowa. No previous reports of interspecific hybridization between these species were found in the literature. Ecological barriers usually separate the parental species; however, at this population, disturbances by grazing animals and yearly fluctuations in the water level allow them to exist sympatrically. The parental species have concurrent flowering periods, similar floral morphology and pigmentation, and are pollinated by non-specific pollinators. The disturbances also provide a wide range of microhabitats intermediate to those of the parents. Thus, hybridization has resulted because of the …
Copulation In Two Species Of Tetraopes: Behavior, Mechanics And Morphology (Coleoptera, Cerambycidae), Thomas John Pilat
Copulation In Two Species Of Tetraopes: Behavior, Mechanics And Morphology (Coleoptera, Cerambycidae), Thomas John Pilat
Master's Theses
No abstract provided.
Ua77/1 Western Alumnus, Vol. 40, No. 2, Wku Alumni Relations
Ua77/1 Western Alumnus, Vol. 40, No. 2, Wku Alumni Relations
WKU Administration Documents
Quarterly magazine created for WKU alumni. Regular features are Hilltopics, Sports, Alumni Newsgrams and Notes and In Memoriam. This issue includes:
- Graduate School (College) is On Its Way
- Evening Class is Thataway
- The Hilltopper Hundred to the Rescue
- ETV - Keep Watching, It's All in Color
- Student Interns Learn How Government Works
- Significant Statements: The New Year Begins
- Good News for Fishermen: Reservoir Research
- There it Was! Your Homecoming - 1971
- Performing Arts Illuminate the Campus Scene
- Discovery 1 - Uncovering the Kentucky of Antiquity
- Discovery 2 - Reviving the Heritage of Kentucky
- Discovery 3 - The Intercultural Studies Program …
The Constant Estrus Rat As A Source Of Viable Ova, John C. Drake
The Constant Estrus Rat As A Source Of Viable Ova, John C. Drake
Morehead State Theses and Dissertations
A Thesis presented to the faculty of the School of Sciences and Mathematics at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science in Biology by John C. Drake, Jr. on September 10, 1971.
Coexistence In Unisexual-Bisexual Species Complexes Of Poeciliopsis (Pisces: Poeciliidae), William S. Moore, Frances E. Mckay
Coexistence In Unisexual-Bisexual Species Complexes Of Poeciliopsis (Pisces: Poeciliidae), William S. Moore, Frances E. Mckay
Biological Sciences Faculty Research Publications
All-female forms of Poeciliopsis rely on males of closely related bisexual species for sperm. The natural habitat of Poeciliopsis in Sonora, Mexico, consists of a variety of small ponds connected by intermittent watercourses. Optimal areas, containing mixed female aggregates, are defended by territorial males. Social structure in natural populations very closely resembles that of laboratory experiments, wherein subordinant males show reduced mate discrimination and inseminate unisexuals.
An equation relating male density to unisexual inseminations is used in a computer simulation model of a population. A stable equilibrium is inherent in unisexual-bisexual species complexes but the level of equilibrium is affected …
Vocalizations Of The Townsend Chipmunk (Eutamias Townsendii), Greig Michael Warner
Vocalizations Of The Townsend Chipmunk (Eutamias Townsendii), Greig Michael Warner
Dissertations and Theses
This study describes and analyzes the vocalizations of the Townsend chipmunk (Eutamias townsendii) in Oregon. Tape recordings of calls were collected primarily from Forest Park in Portland (Oregon) during 1970 and 1971, and sonograms of these recordings were produced. Findings were compared with those of Brand (1970) who investigated E. townsendii vocalizations in California. The prominent calls in the vocal repertoire of townsendii are the quist, the quirt, and the chipper. These calls all appear to be warning calls. The quist note is a a chevron-shaped (A) figure representing a sound which begins at a low frequency (1-2 KC), sharply …