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The Relationship Between Gestational Pcb Exposure, Thyroid Hormones And Adhd, Vicki M Tripoli
The Relationship Between Gestational Pcb Exposure, Thyroid Hormones And Adhd, Vicki M Tripoli
UNLV Retrospective Theses & Dissertations
PCB exposure has been associated with a reduction in circulating thyroid hormones via several different mechanisms. While thyroid hormones can influence many physiological endpoints in adults, precise concentrations during critical periods of gestation are crucial to normal development. Maternal consumption of PCB contaminated fish has been associated with developmental problems in animals and humans. Alterations of thyroid hormones is postulated to be one possible source of the developmental latencies associated with PCB exposure. Thus, this study investigated the influence of maternal thyroxine supplements in rodents exposed to a low dose of commercial PCBs; Pregnant Long-Evans rats were exposed to one …
Short-Term Compensatory And Long-Term Plastic Cardiorespiratory Responses To Hypoxic Exposure, Jutta A Guadagnoli
Short-Term Compensatory And Long-Term Plastic Cardiorespiratory Responses To Hypoxic Exposure, Jutta A Guadagnoli
UNLV Retrospective Theses & Dissertations
Aquatic organisms may encounter multiple perturbations in their environment including but certainly not limited to fluctuations in temperature, salinity, conductivity, pH, carbon dioxide and oxygen content. A large body of work has elucidated the complexity of the cardiovascular system of crustaceans but the intricacies associated with alterations in cardiovascular function with changing environments are elusive. The current body of work focuses on the cardiovascular adjustments that allow crustaceans to survive decreases in oxygen tension; The complexity of control of the open circulatory system of crustaceans has long been underestimated and the marine crustacean, the grass shrimp, P. pugio, which often …
The Effects Of Gestational Perchlorate Exposure On Development And Behavior In Rats, Sally Ann Hopper
The Effects Of Gestational Perchlorate Exposure On Development And Behavior In Rats, Sally Ann Hopper
UNLV Retrospective Theses & Dissertations
Pregnant Long Evans rats were exposed to ammonioum perchlorate in their drinking water at doses of 0.8 mg/kg-day and 8.7 mg/kg-day (or at concentrations of 5.0 mg/L perchlorate and 50.0 mg/L perchlorate) from GD 7-GD 21. The offspring were observed for developmental landmarks and tested in a battery of behavior trials. Dams exposed at the 5.0 mg/kg-day perchlorate exhibited delayed or deficient responses in the number of pups per dam, pinna unfolding, negative geotaxis, startle response IP on PND 61, figure 8 maze on PND 21, and a more reactive tactile startle response on PND 21. Pups exposed at the …
Confidence Intervals For Exposure Risk Assessment, Mark S Kirkham
Confidence Intervals For Exposure Risk Assessment, Mark S Kirkham
UNLV Retrospective Theses & Dissertations
The problem of estimating exposure to a pollutant involves estimation of chemical intake Q. Typically, Q has the form Q = q11q12&cdots;q 1r1/q211q22 &cdots;q2r2t where all thetaij's are unknown means of certain random variables. In assessing the risk to human health from exposure to the pollutant of concern, a confidence interval estimate of Q is needed. In the case of independent normal random variables, point estimates and certain types of interval estimates of a product of several parameters exist in the literature, but not for a ratio of products. In many situations, lot of prior knowledge is available regarding the …
Tadpole Shrimp (Triops Longicaudatus) Responses To Acute And Developmental Hypoxic Exposure, Stacey Lynn Harper
Tadpole Shrimp (Triops Longicaudatus) Responses To Acute And Developmental Hypoxic Exposure, Stacey Lynn Harper
UNLV Retrospective Theses & Dissertations
Tadpole shrimp Triops longicaudatus (Crustacea: Branchiopoda: Notostraca) were reared under normoxic (19--21 kPa O2), moderate (10--13 kPa O2) or severe (1--3 kPa O2) hypoxic conditions to investigate the effects of developmental Po2 (partial pressure of oxygen) on adult metabolic, respiratory and cardiovascular physiology. Growth rates were independent of developmental Po2, although adult body size was significantly smaller in tadpole shrimp reared under severe hypoxic conditions relative to those reared under normoxic conditions. Most organisms increase respiratory surface area in response to hypoxic exposure. Yet growth of the epipodites (proposed respiratory structure) relative to mass (Y = aMb) was significantly reduced …
The Effect Of Exposure, Involvement And Sponsorship Types On Spectator Recognition And Attitude, Tanya Michelle Benson
The Effect Of Exposure, Involvement And Sponsorship Types On Spectator Recognition And Attitude, Tanya Michelle Benson
UNLV Retrospective Theses & Dissertations
The purpose of this research was to examine the effects of sport sponsorships on consumer recognition and attitudes toward the sponsor. This study explored the differences in recognition and attitude among four types of tournament sponsorships (exposition, multi-level, sky box and dummy sponsors). In addition, this study looked at the effects of exposure, involvement and aesthetic qualities on sponsorship recognition. Surveys were administered to spectators at the 1997 Las Vegas Invitational Golf Tournament. Results from this study revealed a significant difference in recognition and attitude among the four different types of sponsorships at the tournament. These differences were attributed to …
The Relationship Between Media Exposure, Personal Experience And Education On The Public's Perceptions Of People With Disabilities: A Correlational Study, Melissa Lynn Reichley
The Relationship Between Media Exposure, Personal Experience And Education On The Public's Perceptions Of People With Disabilities: A Correlational Study, Melissa Lynn Reichley
UNLV Retrospective Theses & Dissertations
The Relationship Between Media Exposure, Personal Experience and Education on the Public's Perceptions of Disabilities seeks to determine whether there is any correlation between people's opinions about people with disabilities (PWDs), and their media consumption, education, and experience or contact with PWDs. The author compares such perceptions between respondents with and without disabilities. While research suggests nondisabled people view people with disabilities to varying degrees of negativity depending on the level and type of disability and accompanying social stigma attached, this researcher questions whether frequency of media exposure is having a positive influence on media consumers' perceptions of PWDs (which …