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Articles 38281 - 38310 of 39279
Full-Text Articles in Entire DC Network
Reproduction And Ecology Of The Jemez Mountains Salamander, Plethodon Neomexicanus, Stephen R. Williams
Reproduction And Ecology Of The Jemez Mountains Salamander, Plethodon Neomexicanus, Stephen R. Williams
Biology ETDs
Plethodon neomexicanus is a salamander endemic to the Jemez Mountains of New Mexico. Only about 10 localities are known, and in the study area one salamander occupies about 10 m2.Adult females are significantly larger than adult males, and the sex ratio is about one for the entire active season which extends from early June to early October. Sexual maturity is reached after 2 to 3 years in males and after 3 years in females. The diurnal ecological maximum and minimum temperatures are 17.0 and 6.0 C, respectively, with an average habitat temperature of 12.2 C. Most of the …
The Role Of The Adrenal Gland In The Survival Of White Rats Subjected To The Parotid Toxin Of The Toad, Bufo Marinus, Mark A. Green
The Role Of The Adrenal Gland In The Survival Of White Rats Subjected To The Parotid Toxin Of The Toad, Bufo Marinus, Mark A. Green
Master's Theses
Six groups of white labor atory rats were utilized in this experiment. A sham-operated group and an adrenalectomized group were used as controls. Four other groups were adrenalectomized and given replacement therapy of cortisone, deoxycorticosterone acetate, epinephrine, and norepinephrine. All groups were then given injections of toad toxin from the parotid glands of Bufo marinus. Their heart and breathing rates were recorded for 60 minutes.
All of the untreated adrenalectomized rats showed altered heart and breathing rates and were killed by the toxin. Cortisone and nor epinephrine aided the adrenalectomiz ed rats to survive. but cortisone was the …
Spacing And Orientation Of The Siphons Of The Tunicate, Styela Plicata, Alfred Page Chestnut
Spacing And Orientation Of The Siphons Of The Tunicate, Styela Plicata, Alfred Page Chestnut
Master's Theses
The spacing and orientation of sipons of Styela plicata (Lesueur)in swift and slow currents were examined. Within aggre crates, the siphons were spaced farther apart in slow currents than in swift currents. The siphons were not horizontally oriented but were vertically oriented in slow currents. The adaptive values of spacing and orientation under different currents are discussed.
Quantitative Growth Relationships Of Microcoleus Vaginatus (Gom.) Ex Drouet And Alcaligenes Sp. In A Sucrose-Salts Medium, James Rexford Brownell
Quantitative Growth Relationships Of Microcoleus Vaginatus (Gom.) Ex Drouet And Alcaligenes Sp. In A Sucrose-Salts Medium, James Rexford Brownell
Master's Theses
The blue-green alga, Microcoleus vaginatus (Gom.) ex Drouet 1968, and a bacterium, Alcaligenes sp., collected from the same habitat, were cultured together and separately in mineral salts media with and without sucrose. Growth of axenic M. vaginatus was stimulated by sucrose. In association with the bacterium in sucrose-containing media algal growth was suppressed, while in inorganic media it was stimulated. Factors involved in this algal-bacterial system probably included competition for the carbon source, changes in pH, and accumulation of cellular waste and lytic products.
An Electrophoretic Comparison Of The Gill Plasma Membrane Proteins Of Freshwater And Saltwater-Adapted Killifish, Fundulus Heteroclitus, Earl Dean Hammit
An Electrophoretic Comparison Of The Gill Plasma Membrane Proteins Of Freshwater And Saltwater-Adapted Killifish, Fundulus Heteroclitus, Earl Dean Hammit
Master's Theses
A study was undertaken to compare proteins present in the gill membranes of freshwater and salt water adapted killifish, Fundulus heteroclitus. For this purpose, a method for the preparation or gill plasma membranes was developed. Polyacrylarnide gel electrophoresis indicated that the two types of gills possessed many membrane proteins in common. However, the freshwater adapted group possessed a single protein not found n the saltwater adapted group and the latter contained a protein not found in the freshwater adapted group.
Aspects Of Reproduction In Myotis Volans, Lasionycteris Noctivagans, And Lasiurus Cinereus, Jay Dee Druecker
Aspects Of Reproduction In Myotis Volans, Lasionycteris Noctivagans, And Lasiurus Cinereus, Jay Dee Druecker
Biology ETDs
The reproductive cycles of Myotis volans, Lasionycteris noctivagans, and Lasiurus cinereus were investigated by examining representative sections of testes and epididymides from 254 males and serially sectioned reproductive tracts of 99 females. Specimens were collected primarily in New Mexico from late March through early October. Spermatogenesis begins in August in M. volans, October in L. noctivagans, and sometime after late September in L. cinereus. Apparently gonadotrophic secretion continues in M. volans until at least the onset of hibernation as numerous mitotic figures, small spermatogonia, and/or a few primary spermatocytes appeared in some males from September and October. During the winter, …
Food And Feeding Habits Of The Rio Grande Mountain-Sucker, Pantosteus Plebeius (Baird And Girard), James A. White
Food And Feeding Habits Of The Rio Grande Mountain-Sucker, Pantosteus Plebeius (Baird And Girard), James A. White
Biology ETDs
The initial purpose of this work was to study the relationship between Pantosteus plebeius (Baird and Girard), the Rio Grande mountain-sucker, and Catostomus commersoni (Lacépède ), the common white sucker, in Jemez Creek drainage, Sandoval County, New Mexico. Because insufficient information on Catostomus commersoni could be obtained, the food and feeding habits of Pantosteus plebeius were studied as an alternative.
Mountain-suckers were captured and observed in Jemez Creek drainage. The intestinal contents of 145 specimens were examined in detail. The intestinal contents of other specimens were examined cursorily.
Pantosteus plebeius are omnivorous and they use a pair of cartilaginous jaw …
A North Temperate Bat Community: Structure And Prey Populations, Hal L. Black
A North Temperate Bat Community: Structure And Prey Populations, Hal L. Black
Biology ETDs
Food habits and food partitioning were investigated in a North Temperate insectivorous bat community. Analysis of fecal pellets showed that all species of bats utilized moths and most species utilized beetles. There appears to be differential utilization of these two prey items. Six species of bats are moth strategists and four species are beetle strategists. In one species, Eptesicus fuscus, changes in food selection is correlated with changes in food abundance.
Food habits are discussed in relation to various parameters of the prey populations, i.e., abundance, activity, and length class diversity. Habitat partitioning is discussed in relation to type of …
A Study Of The Seasonal Incidence Of The Arthropod & Helminth Parasites Of The Prairie Vole, Microtus Ochrogaster, & The Wood Mouse, Peromyscus Leucopus, In An Area Of Warren County, Kentucky, Richard Buckner
Masters Theses & Specialist Projects
One-hundred and fifty Microtus ochrogaster and one-hundred and fifty-five Peromyscus leucopus were examined for arthropod and helminth parasites during a study from November, 1970 through November, 1971. The mean monthly burdens, per host, of each species of parasite and observations on the seasonal incidence of each species are reported.
Nineteen species of arthropod parasites were found; these include eight species of mites, two of chiggers, one of ticks, two of lice, five of fleas, and one of hots. Most of these species exhibited very little host specificity, although there was a definite host preference. Heavier ectoparasite burdens were found on …
Factors Affecting Calcification Processes In The Hermatypic Corals Pocillopora Damicornis And Porites Compressa, Conrad D. Clausen
Factors Affecting Calcification Processes In The Hermatypic Corals Pocillopora Damicornis And Porites Compressa, Conrad D. Clausen
Loma Linda University Electronic Theses, Dissertations & Projects
Temperature affects coral distribution and it also affects rates of physiological processes. Little attention has been given through, to the relation between the basic effect of temperature on reaction rates at the molecular level and its effect on coral distribution at the organismic level. Incubating coral samples in sea water containing 45Ca incorporation as a measure of calcification rate, I studied the effects of temperature on calcification in two coral species, P. damicornis and P. compressa. CaCO3 deposition was chosen because of its basic importance in reef formation. Immediate effects of temperature on calcification rates were studied, as …
The Comparative Histochemistry Of The Infective Oncospheres Of Oochoristica Osheroffi Meggitt, 1934, And Oochoristica Scelopori Voge And Fox, 1950, (Cyclophyllidea: Linstowiidae) With Notes On The Origins Of The Egg Membranes, Gary R. Coulter
Loma Linda University Electronic Theses, Dissertations & Projects
Infective oncospheres of Oochorlstica osheroffi and Oochoristica scelopori were compared using fifteen histochemical tests. Vital stains were also used.
Carnoy’s-fixed gravid proglottids were vacuum-embedded in a paraffin-piccolyte mixture and cut transversely at 6 microns. Sections were tested for the presence of phosphatases, proteins, sclerotin precursors, nucleic acids, carbohydrates and acid mucopolysaccharides.
Oncospheres were histochemlcally very similar. Heavy concentrations of mucoproteins and glycoproteins were detected in the oncospheral coat of O. scelopori. Acid phosphatase was found in the embryophore of O. osheroffi, but could not be demonstrated in O. scelopori. No evidence of a sclerotized egg capsule was …
A Survey Of The Incidence Of Salmonella Among Small Mammals In Central New Mexico, Robert S. Stinson
A Survey Of The Incidence Of Salmonella Among Small Mammals In Central New Mexico, Robert S. Stinson
Biology ETDs
A twelve-month survey of the incidence of Salmonella among small mammals was conducted in central New Mexico, utilizing a direct fecal plating on both selective and enrichment media. Collections were made at the following locations: Albuquerque, Bernardo, Cuba, Isleta Indian Pueblo, Juan Tabo Park, and Moriarty. Locations selected characterize three major types of terrain: mountain, mesa, and river valley. The predominant genera caught in the mountains, in order of their frequency, were Peromyscus, Dipodomys, and Neotoma. The predominant genera caught on the mesas, in order of their frequency, were Peromyscus, Spermophilus, and Dipodomys. The predominant genera caught long the Rio …
Investigation Of Barbel Regeneration In The Catfish Ameiurus Nebulosus, Ruth-Marie E. Griswold
Investigation Of Barbel Regeneration In The Catfish Ameiurus Nebulosus, Ruth-Marie E. Griswold
Senior Scholar Papers
It has been clearly demonstrated that the barbels of Ameiurus nebulosus regenerate completely following amputation. The current investigations involve experimentation dealing primarily with determination of the mechanisms by which regeneration occurs. However, prior to conducting a series of experiments designed to elucidate the processes which initiate regeneration, several preliminary investigations to determine normal barbel structure and regeneration were made.
Brain dissection of an adult catfish confirmed that innervation of the barbels is by both the fifth and seventh cranial nerves, and not solely by the seventh cranial nerve as suggested by Olmstead (1920). Further information regarding normal barbel innervation and …
Psychological Mechanisms In Learning Mathematical Concepts, Louis Fallon
Psychological Mechanisms In Learning Mathematical Concepts, Louis Fallon
Senior Scholar Papers
Psychological Mechanisms in learning Mathematical Concepts: Jean Piaget, the Swiss psychologist, did theoretical and experimental work based on the idea that there is an invariant heirarchy of responses by which everyone acquires mathematical concepts. Basically we tried to use the geometric symmetry concept as a vehicle for studying this process of concept acquisition using subjects ranging in age from three to 25. They were asked to reproduce a series of stimulus "pictures," simple geometric patterns, which could be used without major alteration for each age group. Symmetric responses were divided into four types which were set up into a heirarchy …
Some Aspects Of The Role Of Usnic Acid In Forest Ecology, Yvonne C. Rogers
Some Aspects Of The Role Of Usnic Acid In Forest Ecology, Yvonne C. Rogers
Biology ETDs
Usnea tillandsioides, an aboreal lichen, was observed in great numbers on spruce and fir at an elevation of 11,200 feet in the Sangre de Cristo Range, New Mexico. The amount of fallen lichen material per hectare was estimated. When usnic acid was extracted from lichen thallus, it was demonstrated that the quantity of usnic acid was less in summer lichens than in fall lichens. By soaking lichens in water, it was possible to extract a small amount of usnic acid. However, an examination of rainwater did not indicate that usnic acid was being leached from lichens by rainfall. Soil and …
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.
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 …
Host-Parasite Relationship Studies Of The Larval Alfalfa Weevil And The Ichneumonid Parasite Bathyplectes Curculionis (Thomson), Yeboa A. Duodu
Host-Parasite Relationship Studies Of The Larval Alfalfa Weevil And The Ichneumonid Parasite Bathyplectes Curculionis (Thomson), Yeboa A. Duodu
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The parasitic effects of the ichneumonid Bathyplectes curculionis (Thomson) on the larval alfalfa weevil, Hypera postica (Gyllenhal), were studied.
Results of experiments on the rates of parasitism of the four host larval instars indicated that the first three are either preferred by the parasite over the fourth instar larvae or are more susceptible to the parasite's attack. Survival of the younger weevil larvae after their exposure to female parasites was markedly poorer than that of unparasitized larvae. Premature death of host larvae was probably from both the puncturing by the parasite's ovipositor and the feeding and other activities of parasite …
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 …
Low Temperature Germination Of Tomato Seeds, Dawn M. Gatherum
Low Temperature Germination Of Tomato Seeds, Dawn M. Gatherum
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The purpose of this study was to determine the pattern of inheritance of low temperature germination of tomato. This was accomplished by crossing a tomato (P.I. 341988) that germinates at a low temperature (10 C) with a commercial mechanical harvest cultivar (VF 145-B-7879). The parents, F1, F2, and F3 progenies were tested for low temperature germination responses at 10 C for 15 days. The results show that a single recessive gene is responsible for the low temperature germination character.
Also, a study of the seed coat thickness of the tomatoes VF 145-B-7879 and P.I. 341988 was …
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 …
A Cytological, Morphological, And Anatomical Study Of Elymus Simplex, Stephan L. Hatch
A Cytological, Morphological, And Anatomical Study Of Elymus Simplex, Stephan L. Hatch
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The purpose of this paper is to clarify the taxonomy, report the chromosome number, report meiotic chromosome behavior, and give the anatomy of Elymus simplex Scribner and Williams. The isotype of Elymus simplex and the type description were used to compare this and other species that have been confused.
Cytological and anatomical methods are reported as an aid in clarification of the taxonomic problem that has been associated with this species.
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.
The Relationship Of Soil Temperature And Cytokinin Production In Aspen Invasion, Kristen R. Williams
The Relationship Of Soil Temperature And Cytokinin Production In Aspen Invasion, Kristen R. Williams
Biology ETDs
Quaking aspen (Populus tremuloides Michx.) primarily reproduce by suckering (i.e., root sprouting). Numerous environmental variables have been suggested as causes of this phenomenon, the most notable of which is soil temperature. Studies demonstrating thermal regulation of sprouting indicate the involvement of growth hormones. The only class of hormones to elicit a response similar to sprouting is the cytokinins. Other hormones, no doubt, function in this process as well (e.g., auxins). To substantiate the idea that thermal regulation of sprouting is primarily a function of thermal regulation of cytokinin activity, and to determine the importance of other environmental factors in this …
Altitudinal Variation Of Chlorophyll Concentration And Reflectance Of The Bark Of Populus Tremuloides, William W. Covington
Altitudinal Variation Of Chlorophyll Concentration And Reflectance Of The Bark Of Populus Tremuloides, William W. Covington
Biology ETDs
Chlorophyll concentration and reflectance of bark samples of Populus tremuloides Michx. growing at various elevations in the Sangre de Cristo mountain range of New Mexico indicate the appearance of greener barked trees at higher elevations is due to the reflectance characteristics of a bloom of dead periderm cells and not to increased chlorophyll concentrations. Chlorophyll concentration in aspen bark were, in fact, inversely correlated (p=.001) with altitude.
The higher concentration of chlorophyll at lower elevations is effectively masked by a white bloom which is also characteristic of exposed site trees. At higher elevations the bloom is yellow-brown and more translucent …
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 …