233 Matching Results

Search Results

Advanced search parameters have been applied.

Phytoestrogens in two dioecious species: isolation, characterization and role in plant reproduction

Description: A highly specific steroid regulated transcription system system in Saccharomyces cerevisae was used to screen for phytoestrogens indioecious plants. Yeast cells were co-transformed with a human estrogen receptor expression plasmid and a reporter plasmid containing the E. coli β-galactosidase gene.
Date: May 1996
Creator: Maier, Camelia G. A. (Camelia Gabriela-Anca)
Partner: UNT Libraries

A Physical and Chemical Investigation of Eagle Mountain Lake with Reference to Biological Productivity

Description: The purpose of this investigation is to attempt by correlation of chemical-physical factors to ascertain if any one of the necessary features might act as a factor limiting growth and reproduction of either plants or animals. The body of water used in this investigation is Eagle Mountain Lake, a reservoirs approximately five years of age.
Date: August 1938
Creator: Smith, Burns Ashby
Partner: UNT Libraries

Aspects of fathead minnow reproductive behavior

Description: Following a study of normal reproductive behavior of fathead minnows, Pimephales promelas, experiments were conducted to determine the stability/variability of behavior by sexually mature, territorial males under a variety of manipulated conditions. Collectively, these experiments indicate that although the individual behaviors of fathead minnows appear to be quite variable, the overall process, reproductive behavior, is stable.
Date: May 1988
Creator: Pyron, Mark
Partner: UNT Libraries

CRS Issue Statement on Abortion, Family Planning, and Reproductive Health

Description: The 111th Congress will likely consider a variety of issues involving family planning and reproductive health. Legislation related to family planning and Title X of the Public Health Service Act, including appropriations measures that could affect the funding of Title X family planning initiatives, is expected.
Date: March 13, 2009
Creator: Shimabukuro, Jon O.
Partner: UNT Libraries Government Documents Department

Performance of Planted Herbaceous Species in Longleaf Pine (Pinus palustris Mill.) Plantations: Overstory Effects of Competition and Needlefall

Description: Research to determine the separate effects of above-ground and below-ground competition and needlefall of over-story pines on under-story plant performance. Periodic monitoring of over-story crown closure, soil water content, temperature, and nutrients were conducted. Results indicate competition for light had a more determental effect on performance of herbaceous species in longleaf pine plantations than that resulting from competition for below-ground resources.
Date: July 3, 2001
Creator: Dagley, C.M.
Partner: UNT Libraries Government Documents Department

VARIATIONS IN REPRODUCTIVE TOXICANT IDENTIFICATION

Description: Reproductive toxicants are a very important class of compounds. They present unique hazards to those of child bearing ages, perform their 'dirty work' using a wide variety of mechanisms on a number of different organs, and are regulatorily important. Because of all of this, properly identifying reproductive toxicants is important, but fraught with difficulty. In this paper we will describe types or reproductive toxicants, their importance, and both mistakes and good practices that people who are not experts in reproductive toxicology may use in their attempts to identify them. Additionally, this paper will focus on chemical reproductive toxicants and will not address biological agents that could affect reproductive toxicity although many principles outlined here could be applied to that endeavor.
Date: May 13, 2008
Creator: Simmons, F
Partner: UNT Libraries Government Documents Department

Lake Roosevelt Rainbow Trout : Habitat/Passage Improvement Project Annual Report 1999.

Description: Lake Franklin D. Roosevelt was created with the completion of the Grand Coulee Dam in 1942. The lake stretches 151 miles up-stream to the International border between the United States and Canada at the 49th parallel. Increased recreational use, subsistence and sport fishing has resulted in intense interest and possible exploitation of the resources within the lake. Previous studies of the lake and its fishery have been limited. Early studies indicate that natural reproduction within the lake and tributaries are not sufficient to support a rainbow trout (Onchoryhnchus mykiss) fishery (Scholz et. al., 1988). These studies indicate that the rainbow trout population may be limited by lack of suitable habitat for spawning and rearing (Scholz et. al., 1988). The initial phase of this project (Phase I, baseline data collection- 1990-91) was directed at the assessment of limiting factors such as quality and quantity of available spawning gravel, identification of passage barriers, and assessment of other limiting factors. Population estimates were conducted using the Seber/LeCren removal/depletion method. After the initial assessment of stream parameters, several streams were selected for habitat/passage improvement projects (Phase II, implementation-1992-96). At the completion of project habitat improvements, the final phase (Phase III, monitoring) began. This phase will assess changes and gauge the success achieved through the improvements. The objective of the project is to correct passage barriers and improve habitat conditions of selected tributaries to Lake Roosevelt for adfluvial rainbow trout that utilize tributary streams for spawning and rearing. Streams with restorable habitats were selected for improvements. Completion of improvement efforts should increase the adfluvial rainbow trout contribution to the resident fishery in Lake Roosevelt. Three co-operating agencies, the Confederated Tribes of the Colville Reservation (CCT), the Spokane Tribe of Indians (STI) and the Washington Department of Fish and Wildlife initiated the project fieldwork in 1990. ...
Date: February 1, 2000
Creator: Jones, Charles D.
Partner: UNT Libraries Government Documents Department

Lake Roosevelt Rainbow Trout : Habitat/Passage Improvement Project Annual Report 2000.

Description: Lake Franklin D. Roosevelt was created with the completion of the Grand Coulee Dam in 1942. The lake stretches 151 miles up-stream to the International border between the United States and Canada at the 49th parallel. Increased recreational use, subsistence and sport fishing has resulted in intense interest and possible exploitation of the resources within the lake. Previous studies of the lake and its fishery have been limited. Early studies indicate that natural reproduction within the lake and tributaries are not sufficient to support a rainbow trout (Onchoryhnchus mykiss) fishery (Scholz et. al., 1988). These studies indicate that the rainbow trout population may be limited by lack of suitable habitat for spawning and rearing (Scholz et. al., 1988). The initial phase of this project (Phase I, baseline data collection- 1990-91) was directed at the assessment of limiting factors such as quality and quantity of available spawning gravel, identification of passage barriers, and assessment of other limiting factors. Population estimates were conducted using the Seber/LeCren removal/depletion method. After the initial assessment of stream parameters, several streams were selected for habitat/passage improvement projects (Phase II, implementation-1992-96). At the completion of project habitat improvements, the final phase (Phase III, monitoring) began. This phase will assess changes and gauge the success achieved through the improvements. The objective of the project is to correct passage barriers and improve habitat conditions of selected tributaries to Lake Roosevelt for adfluvial rainbow trout that utilize tributary streams for spawning and rearing. Streams with restorable habitats were selected for improvements. Completion of improvement efforts should increase the adfluvial rainbow trout contribution to the resident fishery in Lake Roosevelt. Three co-operating agencies, the Confederated Tribes of the Colville Reservation (CCT), the Spokane Tribe of Indians (STI) and the Washington Department of Fish and Wildlife initiated the project fieldwork in 1990. ...
Date: February 1, 2001
Creator: Sear, Sheri
Partner: UNT Libraries Government Documents Department

The Effect of Memory Requirement on Schema Learning

Description: A number of previous investigations have suggested that schema learning would be more readily facilitated by a recognition task than a reproduction task due to the increased memory requirement of the reproduction task. Differential memory requirements of 0, 4, 8, 16 and 32 seconds were imposed on 50 Ss in a recognition task to determine if increased memory requirements improved schema learning in the same mode as the reproduction task. The results indicated no significant improvement in schema learning with increased memory requirement. The data does suggest negative transfer from reproduction to recognition task. Recommendations for design and procedural improvements are included.
Date: May 1973
Creator: Buckner, Rose Laminack
Partner: UNT Libraries

The Propagation of Plants

Description: Report discussing brief and practical suggestions for propagating plants from both seeds and cuttings. Layering, grafting, and budding are also discussed.
Date: 1902
Creator: Corbett, L. C. (Lee Cleveland), 1867-1940
Partner: UNT Libraries Government Documents Department

The Reproductive Consequences of Carriers of Methylenebisacrylamide-Induced Balanced Reciprocal Translocations in Mus Musculus

Description: N,N'-methylenebisacrylamide (MBA) was studied because of its effectiveness in inducing heritable translocations in germ cells of male mice. The health impact of translocations was studied through anatomical analysis of the progeny of semisterile translocation carriers. As expected, the semisterility of translocation carriers resulted primarily from embryonic death during periimplantation stages due to unbalanced chromosome sperm segregants. Among conceptuses that survived to mid- and late-gestation stages, there was an increased incidence of developmental anomalies including fetal death and phenotypic defects. These abnormalities are associated with unbalanced chromosome complements that allow survival to the later stages of development.
Date: May 1989
Creator: Kile, Joanna L. (Joanna Le)
Partner: UNT Libraries

Effect of the Operation of Kerr and Hungry Horse Dams on the Reproduction Success of Kokanee in the Flathead River System, 1986 Annual Progress Report.

Description: The 1985 kokanee spawning run in the Flathead system was the strongest in five years. Escapement to the Flathead River system was 147,000 fish, including 123,000 in McDonald Creek and an estimated 20,000 in the main stem. Enumeration of spawners and redds in the Flathead River was hindered by high fall flows and early freezing in November. The upstream spawning migration from Flathead Lake began in late August. Schools of kokanee were seen six miles above the lake on September 4. We counted 1,156 redds in Flathead Lake, distributed primarily along the southeastern shore. An unusually high proportion (90 percent) of lakeshore spawning occurred in the zone above minimum pool, where egg mortality is very high because of exposure from drawdown. Escapement to the Swan River was 1,350 fish. Four year old (III+) fish comprised 95 percent of the spawning run in the Flathead system. This continues a five-year trend toward dominance of the III+ year class. The age composition of spawners has varied considerably for the past 15 years. The average size of spawning fish was 365 mm, which is identical to the average size of the parent year class in 1981. One of the goals of managing Flathead kokanee is to produce mature fish 300-330 mm in length. In the main stem Flathead River, pre-emergent survival was 80 percent. Survival in McDonald Creek, unaffected by hydroelectric operations, was 83 percent. Sampling showed few hatched alevins, probably due to unusually cold winter temperatures. Egg survival at Blue Bay, a spawning area on Flathead Lake where redds are concentrated below minimum pool, varied in relation to depth and dissolved oxygen concentration in the substrate. Eggs survived 78 days at 2,880 feet where dissolved oxygen was 5.7 mg/l. Eggs survived 35 days at 2,870 feet where dissolved oxygen concentration averaged 2.9 ...
Date: March 1, 1987
Creator: Beattie, Will & Clancey, Patrick
Partner: UNT Libraries Government Documents Department

Effect of the Operation of Kerr and Hungry Horse Dams on the Reproductive Success of Kokanee in the Flathead System, 1987 Final Report.

Description: Studies of kokanee reproductive success in the Flathead system from 1981 to 1987 have assessed the losses in fish production attributable to hydroelectric operations. We estimated that the Flathead Lake shoreline spawning stock has lost at least 50,000 fish annually, since Kerr Dam was completed in 1938. The Flathead River spawning stock has lost 95,000 spawners annually because of the operations of Hungry Horse Dam. Lakeshore spawning has been adversely affected because Flathead Lake has been drafted to minimum pool during the winter when kokanee eggs are incubating in shallow shoreline redds. Egg mortality from exposure and desiccation of kokanee redds has increased since the mid 1970's. When the lake was drafted more quickly and held longer at minimum pool. Escapement surveys in the early 1950's, and a creel survey in the early 1960's have provided a baseline to which the present escapement levels can be compared, and loss estimated. Main stem Flathead River spawning has also declined since the mid 1970's when fluctuating discharge from Hungry Horse Dam during the spawning and incubation season exposed redds at the river margin and increased mortality. This decline followed an increase in main stem spawning in the late 1950's through the mid 1960's attributable to higher winter water temperature and relatively stable discharge from Hungry Horse Dam. Spawning escapement in the main stem exceeded 300,000 kokanee in the early 1970's as a result. Spawning in spring-influenced sites has comprised 35 percent of the main stem escapement from 1979 to 1986. We took that proportion of the early 1970's escapement (105,000) as the baseline against which to measure historic loss. Agricultural and suburban development has contributed less significantly to degradation of kokanee spawning habitat in the river system and on the Flathead Lake shoreline. Their influence on groundwater quality and substrate composition has ...
Date: May 1, 1988
Creator: Beattie, Will; Zubik, Raymond & Clancey, Patrick
Partner: UNT Libraries Government Documents Department

Toxicology Studies on Lewisite and Sulfur Mustard Agents: Two-Generation Reproduction Study of Lewisite in Rats Final Report

Description: Occupational health standards have not been established for Lewisite [bis(2-chlorethyl)arsine], a potent toxic vesicant which reacts with the sulfhydryl groups of proteins through its arsenic group. The purposes of this study were to determine the reproductive consequences and dose~response of continuing Lewisite exposure of parental males and females and their offspring in a 42-week two-generation study. Solutions of Lewisite were prepared for administration by diluting the neat agent with sesame oil. Rats were administered Lewisite (0, 0.10, 0.25 or 0.60 mg/kg/day for 5 days a week) via intragastric intubation prior to mating, during mating and after mating until the birth of their offspring. The dams continued to receive Lewisite during lactation. At weaning, male and female offspring of each group were selected to continue on the study; rece1v1ng Lewisite during adolescence, mating and throughout gestation. Again, the dams continued to receive Lewisite until weaning of the offspring. Lewisite had no adverse effect on reproduction performance, fertility or reproductive organ weights of male or female rats through two consecutive generations. No adverse effect to offspring were attributed to Lewisite exposure. Minor changes in growth was the only maternal effect observed. Lewisite exposure of parental rats caused no gross or microscopic lesions in testes, epididymis, prostrate, seminal vesicles, ovaries, uterus or vagina. Severe inflammation of the lung was observed at necropsy in cases in which Lewisite gained access to the respiratory system from accidental dosing or reflux and aspiration; this usually caused early death of the animal. The NOEL for reproductive effects in this study was greater than 0.60 mg/kg/day.
Date: July 15, 1989
Creator: Sasser, L. B.; Cushing, J. A.; Kalkwarf, D. R.; Mellick, P. W. & Buschbom, R. L.
Partner: UNT Libraries Government Documents Department

Conceptual Plans for Qualitatively and Quantitatively Improving Artificial Propagation of Anadromous Salmonids in the Columbia River Basin.

Description: In 1984, the Northwest Power Planning Council (Council) amended its Fish and Wildlife Program (Program) to include an Action Plan (Section 1500), to give focus and priority directions to various aspects of the Program. Regarding improved hatchery effectiveness, Bonneville Power Administration (BPA) was requested to evaluate ongoing work under 704(h) and submit a workplan to cover future efforts. This report provides concepts for increasing hatchery effectiveness. Additionally, it proposes numerical goals for increased fish production, identifies ways to accomplish them and lists supportive objectives, project schedules, and preliminary budgeting information. Preliminary data from subbasin planning indicates a large additional need for artificially reared salmon and steelhead in the Columbia River Basin. The total need depends upon many factors and this information will be developed and refined as subbasin plans are completed. Recently constructed fish hatcheries are coming on line, and other hatcheries are expected to be prescribed. This workplan is directed at increasing fish propagation at existing facilities, as described in program Section 700. In doing this, four approaches were considered and evaluated: (1) purchasing smolts from commercial resources; (2) building additional but typical hatcheries; (3) modifying existing hatcheries to increase their production with supplemental oxygen; and (4) increasing smolt quality to increase survival, via various supportive actions.
Date: October 1, 1986
Creator: Bouck, Gerald R.
Partner: UNT Libraries Government Documents Department

Grasshoppers and Their Control on Sugar Beets and Truck Crops

Description: This report discusses grasshoppers, which destroy sugar beets and truck crops, and methods for controlling grasshoppers in the light of recent outbreaks in the mid-western United States, particularly in Kansas. The reproductive practices of grasshoppers and their preferred climatic conditions are given special attention.
Date: 1915
Creator: Milliken, F. B.
Partner: UNT Libraries Government Documents Department

The Histological Effects of Injections of Fish Pituitary Extracts on the Testes of Male Frogs, (Rana Pipiens), and the Reproductive System of Immature Mice

Description: The purpose of this investigation was first, to make a histological and cytological study of the testis of male frogs, Rana pipiens, and to determine if there were tissue or cellular changes as well as physiological effects caused by fish pituitary-extract injections. Second, to determine if injections of fish pituitary extract into immature female white mice caused histological changes in the ovaries and uteri.
Date: 1949
Creator: Robertson, William George
Partner: UNT Libraries