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Articles 271 - 291 of 291
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Community Structure Of The Arthropods Of Carlsbad Cavern Emphasizing Raphidophoridae Of The Genus Ceuthophilus, Diana Northup
Community Structure Of The Arthropods Of Carlsbad Cavern Emphasizing Raphidophoridae Of The Genus Ceuthophilus, Diana Northup
Biology ETDs
Censusing of cave arthropods has been carried out in three areas of Carlsbad Cavern from 1984 to 1987, using pitfall traps. The areas represent a food rich area (Bat Cave, a guano community with high species richness), a food poor area (Sand Passage, an area deep within the cave, with low species richness), and an area with moderate food resources (Left Hand Tunnel, an area near the Underground Lunch Room). Species diversity, as estimated by Hill's N2, showed that Left Hand Tunnel had values closer to one ( dominance by one species), while Sand Passage and Bat Cave …
Effects Of Body Condition On Reproductive Performance Of Range Beef Cows, Patrick A. Momont
Effects Of Body Condition On Reproductive Performance Of Range Beef Cows, Patrick A. Momont
Electronic Theses and Dissertations
A 3 yr. 22 factorial study was conducted with 133 mature Simmental X Angus cows calving for 81 d beginning in mid-March to determine minimum cow body condition required for adequate reproductive performance of range beef cows. Two levels of early (early December to mid-February) and late (from calving date to early May) winter nutrition were imposed. Nutritional treatments produced total winter (December-May) weight changes ranging from -188 to -5 kg and wide cow body condition differences at calving and breeding. The breeding season lasted 60-70 d beginning June 5 each yr. Visual condition scores (CS 1-9, l=thin), weight to …
The Effects Of Photoperiod And Melatonin Injections On The Reproductive System Of The Male Mongolian Gerbil (Meriones Unguiculatus), Luis Jose Cova Marchan
The Effects Of Photoperiod And Melatonin Injections On The Reproductive System Of The Male Mongolian Gerbil (Meriones Unguiculatus), Luis Jose Cova Marchan
Master's Theses
This work was undertaken to study the effects of photoperiod and melatonin on fertility in male Mongolian gerbils (Meriones unguiculatus). Four groups of fifteen animals each, were placed in different photoperiods (ambient, ranging from 14L:10D to 11.3L:12.3D; 24L:10D; 14L:10D; and 1L:23D). After 35 days, three gerbils from each photoperiod condition were sacrificed and the testes, epididymides, seminal vesicles, prostate, kidneys, adrenals, thymus and hypophysis were weighed. The testes and epididymides were placed in Bouin's fixative and used for histological studies. Also, two males from each photoperiod condition were paired individually with a female. The remaining animals of each photoperiod condition …
A Comparison Of The Perception Of Juxtaposed Tones In Newspaper Images When Screened With Conventional And Random Dot Screens, Sylvia Monteiro
A Comparison Of The Perception Of Juxtaposed Tones In Newspaper Images When Screened With Conventional And Random Dot Screens, Sylvia Monteiro
Theses
The halftone process has been the conventional means of reproducing photographic artwork on newsprint. The use of relatively coarse screen rulings, dictated by the paper characteristics, produces an image with a noticeable dot pattern. Furthermore, the printing process is susceptible to extreme dot gain variation, which affects tone reproduction and the pictorial communication of the image. There were good reasons to suspect that a random dot screen could give more consistent tone rendition than a conventional halftone screen. A comparative study of the consistency of perception of conventional and randomly screened images when printed on newsprint has not yet been …
Courtship And Reproduction In The Bali Mynah, Leucopsar Rothschildi (Aves : Sturnidae), Ann Patterson Marshall
Courtship And Reproduction In The Bali Mynah, Leucopsar Rothschildi (Aves : Sturnidae), Ann Patterson Marshall
University of the Pacific Theses and Dissertations
Reproductive behavior of captive Bali Mynahs (Leucopsar rothschildi) was studied at the Smithsonian Institution's Conservation and Research Center, Front Royal, Virginia. Courtship and copulation are followed by egg-laying, then incubation, hatching, brooding and feeding, fledging, and feeding. Parents become aggressive toward their young at the start of a new reproductive period, marked by a renewal of courtship.
The female does the majority of the incubation, brooding, and feeding of the young, although the male participates as well. The male performs both the bobbing· display and the crest display more than the female does. During these displays, the crest is prominently …
The Effects Of Photoperiod And Melatonin Injections On The Reproductive System Of Male Mice, Mus Musculus, Icr Strain, Margaret Ann Shugart
The Effects Of Photoperiod And Melatonin Injections On The Reproductive System Of Male Mice, Mus Musculus, Icr Strain, Margaret Ann Shugart
Master's Theses
The reproductive effects of long (24L:OD), natural (14L:lOD), and short (1L:23D) photoperiods were studied in the male mouse, Mus musculus, ICR strain. One third of the mice in each photoperiodic regimen were sacrificed after 45 days. Half of the remaining mice in each regimen received daily melatonin (5-methoxy-N-acetyl tryptamine) injections for 45 additional days. Body weights, testicular and accessory sex organ weights were measured and microscopic examinations of the testes were made. Plasma testosterone levels were determined using radioimmunoassay. Other organ (pituitary, kidney, adrenal, thymus, thyroid) weights were also obtained.
Observations On The Reproductive Morphology Of Some California Spionid Polychaetes, F. Scott Mceuen
Observations On The Reproductive Morphology Of Some California Spionid Polychaetes, F. Scott Mceuen
University of the Pacific Theses and Dissertations
This study considers the morphology of the sperm, nephridia, seminal receptacles, and gonads among a number of California spionid species. The data collected provide support for the general observation of other workers.
Feeding Habits And Reproduction Of Three Sympatric Lizard Species From West-Central Utah, John B. Andre
Feeding Habits And Reproduction Of Three Sympatric Lizard Species From West-Central Utah, John B. Andre
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The feeding habits and reproduction of Uta stansburiana, Crotaphytus collaris and Cnemidophorus tigris during spring and summer 1976 are described. Feeding habits are expressed in percent total number and volume of prey items and frequency of occurrence of each prey category. Importance Values are also calculated. These values better illustrate the feeding habits of the lizard species than either percent total number and volume and frequency of prey category occurrence.
Lizards consume a variety of food items throughout the growing season. Hymenoptera, Coleoptera, Orthoptera and Arachnida are the major prey categories of U. stansburiana. The major prey categories …
Contributions To The Reproductive Biology And Natural History Of The Pirateperch, Aphredoderus Sayanus, Edward O. Murdy
Contributions To The Reproductive Biology And Natural History Of The Pirateperch, Aphredoderus Sayanus, Edward O. Murdy
Biological Sciences Theses & Dissertations
The purpose of this study was to describe the micro and macro-anatomy of the reproductive system and the testicular and ovarian development in Aphredoderus sayanus.
Specimens were collected at least once a month from September, 1976, through May, 1977, in Cypress Pond, a part of the Dismal Swamp drainage, outside of Suffolk, Virginia. Forty-three specimens had their gonads examined histologically, of these 13 were males, 29 were females and in one specimen the sex was not determinable.
Aphredoderus sayanus is a spring spawner, spent gonads were found on and after April 13, 1977. Gonads began to ripen in the …
Localization Of Neurosecretory Cells Within The Cerebral Ganglia Of Amphiphorus Imparispinosus Griffin, 1898 (Hoplonemertea) And Their Possible Regulatory Role In The Annual Reproductive Cycle, Gail H. Jacobson
Dissertations and Theses
Nemerteans are common invertebrates along coastlines in both temperate and arctic climates throughout the world. Amphiphorus imparispinosus is a carnivorous member of this phylum that is found abundantly in the intertidal areas of the Oregon coast. As in many other invertebrate phyla, endocrine integration within the nemerteans is thought to be accomplished by neurosecretory mechanisms. In Amphiphorus the presence of these neurosecretory systems has not been previously shown. This project was undertaken to determine if neurosecretory cells are present within the central nervous system of this species and. further, to examine seasonal changes in the number and appearance of these …
The Effect Of Photoperiod On The Regressive Phase Of The Ovarian Cycle Of The Lizard, Anolis Carolinensis., John Dickens Pinch
The Effect Of Photoperiod On The Regressive Phase Of The Ovarian Cycle Of The Lizard, Anolis Carolinensis., John Dickens Pinch
Master's Theses
The effects of constant photoperiod (14 hours of light) and decreasing photoperiod (13-8 hours of light) on the regressive phase of the ovarian cycle of the lizard Anolis carolinensis were investigated. Changes in body, liver, ovary and oviduct weights were measured and microscopic examinations of several ovarian parameters were made. In both light regimens body and liver weights decreased over the first four weeks of the experiment but both increased at the sixth week. In addition, ovary weight was highly variable but exhibited a decreasing trend and oviduct weight decreased. There were decreases in the number of previtellogonic follicles and …
Reproduction By Adfluvial Salmonids In Spawn Creek, Cache County, Utah, David R. Bernard
Reproduction By Adfluvial Salmonids In Spawn Creek, Cache County, Utah, David R. Bernard
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The migration and production of indigenous populations of brown, brook, and cutthroat trouts in Spawn Creek, Cache County, Utah, were studied in 1973 and 1974 to elucidate the role of this stream vis-a-vis the rest of the watershed. Spawn Creek and its watershed were described climatically, hydrologically, geologically, vegetatively, recreationally, and chemically. The prevalent, aquatic taxa of fauna and flora were also listed. The equipment and techniques used in the study to collect data, including a two-way fish trap and electro-fishing gear, were delineated. The collected data consisted of periodic estimates of mean weight and density stratified by year classes. …
Effects Of Heavy Metals (Cadmium, Copper, And Mercury) On Reproduction, Growth, And Survival Of Brine Shrimp (Artemia Salina) From The Great Salt Lake, Karl A. Gebhardt
Effects Of Heavy Metals (Cadmium, Copper, And Mercury) On Reproduction, Growth, And Survival Of Brine Shrimp (Artemia Salina) From The Great Salt Lake, Karl A. Gebhardt
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The purpose of this paper is to report findings concerning the effects of cadmium, copper, and mercury on the brine shrimp Artemia Salina, of the Great Salt Lake. Metal toxicity was observed in relation to acute susceptibility, growth, reproduction, and hatching of the brine shrimp.
Heavy metal concentrations such as cadmium, copper, and mercury are known to be considerably higher in the Great Salt Lake than those in both freshwater and seawater. No published study has been concerned with heavy metal effects on organisms in salinities greater than seawater (35 grams per liter total dissolved solids). The experiments reported …
Reproductive Parameters For Nine Avian Species At Moore Creek, Merritt Island National Wildlife Refuge, G. Tanner Girard
Reproductive Parameters For Nine Avian Species At Moore Creek, Merritt Island National Wildlife Refuge, G. Tanner Girard
Retrospective Theses and Dissertations
No abstract provided.
Reproduction And Hematology Of The Cache Elk Herd, Thomas B. Follis
Reproduction And Hematology Of The Cache Elk Herd, Thomas B. Follis
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The initial three years of a 10-year reproductive study of elk involved three major phases. A fourth was added because of convenience. Objective 1 was to ascertain pregnancy rates in yearling and mature elk by rectal palpation, associate these rates with subsequent fall cow/calf ratios, and to test concurrently an ultrasonic fetal heart detector. Rectally observed anatomical changes in gravid uteri of cattle were directly applicable to elk. Ultrasonic detections of pregnancies in elk and deer were unsuccessful.
Pregnancy rates in the 1969-70 winter of 100 and 0 percent, respectively, for 19 adult and five yearling elk were associated with …
Asexual Reproduction In Planaria Characteristics Of The Inhibitor(S), Linda Gail Sheffield
Asexual Reproduction In Planaria Characteristics Of The Inhibitor(S), Linda Gail Sheffield
Theses and Dissertations
A study was made of the postulated fission-inhibiting substance located in the cephalic region of Dugesia dorotocephala. Rearing decapitated planaria in four different concentrations (25, 50, 75 or 100 ug/ml) of head or whole body extract resulted in a positive correlation between the inhibition of fission rate and the concentration of extract. The difference in inhibitory activity between the two types of extracts was three percent at maximum. The inhibitory substance was partially inactivated at 60° C. There was a direct correlation between the length of time that the extract was heated and the inactivation of inhibitor. The active substance …
Asexual Reproduction In Planaria Studies On Inhibition, Hal R. Fitzgerald
Asexual Reproduction In Planaria Studies On Inhibition, Hal R. Fitzgerald
Theses and Dissertations
The invertebrates display several methods of asexual reproduction, such as fission and gemnule formation and budding (Hay, 1966). Planaria reproduce asexually only by fission.
Reproductive Biology Of Thais Emarginata (Deshayes, 1839) And Thais Canaliculata (Dulcos, 1832), Roy Seamands Houston
Reproductive Biology Of Thais Emarginata (Deshayes, 1839) And Thais Canaliculata (Dulcos, 1832), Roy Seamands Houston
University of the Pacific Theses and Dissertations
Thais emarginata (Deshayes, 1839) and Thais canaliculata (Dulcos, 1832), are two common Pacific coast gastropods (Family: Muricidae). T. emarginata is found in semi-protected rocky areas from Alaska to Baja California, while T. canaliaulata occurs in quiet bays from Alaska to Monterey Bay, California (Ricketts and Calvin, 1966). Both species occur on rocks and jetties where they can be seen feeding upon barnacles and young mussels. Despite the abundance of these species their reproductive biology has not been examined.
In the present study, the following aspects of the reproductive biology of T. emarginata and T. canalieulata are presented: Relationship of gonadal …
The Effect Of Cattle, Sheep, And Other Factors On Aspen (Populus Tremuloides) Reproduction After Clear-Cut Logging In Southern Utah, Paul A. Lucas
The Effect Of Cattle, Sheep, And Other Factors On Aspen (Populus Tremuloides) Reproduction After Clear-Cut Logging In Southern Utah, Paul A. Lucas
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Aspen is the most widespread deciduous tree of the western United States and the aspen type is important for water, forage, and wood products. Aspen reproduction on cutover areas was thought to be hindered by browsing and other factors, therefore a study was conducted to determine the effects of livestock, pocket gophers, disease, and snowpack damage on aspen reproduction during the first three years after clear-cutting. An enclosure was constructed and divided into nine paddocks. Controlled grazing by cattle and sheep was applied to six different paddocks during three summer periods. Three paddocks were protected from grazing. Results show that …
The Concept Of Brahmacarya, Evelyn Vrat
The Concept Of Brahmacarya, Evelyn Vrat
University of the Pacific Theses and Dissertations
Contemporary civilization of the western world represents a combination of material development and moral degeneration, Value is measured in 'space' not in 'spirit'. Antecedent to the complications of life with its sufferings) 'fiddlers fees' and disillusionments, how very few realize that true pleasure is not in having, but in being? Fewer still are those whose feelings, thoughts and actions are conscious, aware, self-chosen and self-directed. More often than not, introspection reveals that most are not masters, but the mastered, victims of moods and conflicts...
However, deep dissatisfaction with life as it appears to be and with the individual's adaption to …
Hypothyroidism In Relation To Reproduction, James J. Embick
Hypothyroidism In Relation To Reproduction, James J. Embick
MD Theses
No abstract provided.