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Passive Integrated Transponders In Gila Elegans: Location, Retention, Stress, And Mortality, Andrea Dee Montony
Passive Integrated Transponders In Gila Elegans: Location, Retention, Stress, And Mortality, Andrea Dee Montony
UNLV Retrospective Theses & Dissertations
Despite large-scale propagation and rearing efforts few of the critically endangered bonytail, Gila elegans, are recovered following release from hatcheries. This study tested the role of passive integrative transponder (PIT) tag loss and tagging associated stress and mortality in these low recoveries. Bonytail exhibited 98-100 percent tag retention regardless of insertion direction (ventral toward anterior and anterior toward ventral). Plasma cortisol levels were measured at 0, 0.5, 3, 6, 12, and 24 hours following PIT-tagging in fish held at three temperatures (12, 16, and 20°C) as an indicator of stress. Bonytail tagged at 16°C had significantly lower plasma cortisol levels …
Molecular Mechanisms Controlling Hormonal Regulation Of Plant Responses To Elevated Carbon Dioxide And Abiotic Stresses, Xiaolu Zou
UNLV Retrospective Theses & Dissertations
Global climate change due to elevated atmospheric [CO2] and abiotic stresses have a strong impact on the establishment, survival and reproduction of plants. The goal of my research is to understand the molecular mechanism by which hormones regulate plant responses to elevated CO2 and abiotic stresses. Abscisic acid (ABA) is well known as a stress hormone, which also promotes seed formation and dormancy, and inhibits seed germination. In contrast, another hormone, gibberellin (GA) breaks seed dormancy and promotes seed germination and post-germination growth including flowering. The focus of my research is to study the functions of a group of transcription …
A Model Of The Interplay Of Culture And Immigration Stress In The Development And Maintenance Of Alcohol-Related Disorders In Hispanic/Latino Immigrants, Marilyn J Strada
A Model Of The Interplay Of Culture And Immigration Stress In The Development And Maintenance Of Alcohol-Related Disorders In Hispanic/Latino Immigrants, Marilyn J Strada
UNLV Retrospective Theses & Dissertations
The Hispanic/Latino population represents the largest ethnic minority group in the United States, with immigrants comprising a substantial portion of this population. For both U.S.-born and immigrant Hispanic/Latinos, alcohol abuse and dependence is of particular concern given their reported high prevalence rates, the severe alcohol-related consequences that they experience, and the various barriers to obtain treatment that they encounter. In comparison to members of other ethnic groups, Hispanics/Latinos have the lowest rates of perceived need for treatment, the lowest past and current rates of participation in treatment and the highest dropout rates after attending just one counseling session. Although there …
Characterization Of Residual Stress And Defects In Welded Specimen, Srinivas Chanda
Characterization Of Residual Stress And Defects In Welded Specimen, Srinivas Chanda
UNLV Retrospective Theses & Dissertations
The residual stresses developed at different locations of welded specimens consisting of austenitic Type 304L stainless steel (SS) and/or martensitic Alloy EP-823 has been characterized in terms of S-, W- and T-parameters based on a classical positron annihilation spectroscopy (PAS) technique. The resultant data indicate that the magnitude of residual stress was higher near the fusion-line (FL) compared to that of the base region of the welded specimen consisting of similar materials on both sides. However, for welded specimens of dissimilar materials on opposite side, the extent of residual stress was somewhat lower at the FL compared to that of …
Investigating Stress Related To Beginning Teacher Standards, Michelle Dupree
Investigating Stress Related To Beginning Teacher Standards, Michelle Dupree
UNLV Retrospective Theses & Dissertations
The purpose of this study was to investigate the levels of stress experienced by novice special education teachers related to The Council for Exceptional Children national standards for beginning teachers. The Participants in this study were novice resource room and novice self-contained teachers in the Clark County School District. Data were collected using the Teacher Stress Survey. This survey measured levels of stress experienced by novice special education resource room and self-contained teachers at the beginning and end of the first semester; There was no statistically significant difference in total reported stress between self-contained and resource room teachers. There was …
Ethnic Differences Among Maltreated Youths With Respect To Posttraumatic Stress Disorder And Related Symptoms, Amie Marie Lemos-Miller
Ethnic Differences Among Maltreated Youths With Respect To Posttraumatic Stress Disorder And Related Symptoms, Amie Marie Lemos-Miller
UNLV Retrospective Theses & Dissertations
Symptoms associated with the development and maintenance of Posttraumatic Stress Disorder (PTSD) were examined in a diverse group of maltreated adolescents. The first hypothesis was that levels of PTSD symptomatology, depression, dissociation, anger, and maladaptive cognitions were expected to significantly differ among African-American, Caucasian, Hispanic, and Multiracial adolescents. The second hypothesis was that ethnicity was expected to significantly moderate a relationship between (1) severity of PTSD as measured by symptomatology, and (2) the expression of related symptoms (i.e., depression, dissociation, anger, and maladaptive cognitions). Regarding hypothesis one, African-Americans reported less depressive symptoms overall than other ethnic groups, with Caucasians and …
Residual Stress Characterization And Defects Analyses By Microscopy, Subhra Bandyopadhyay
Residual Stress Characterization And Defects Analyses By Microscopy, Subhra Bandyopadhyay
UNLV Retrospective Theses & Dissertations
The structural material to contain the spallation target during transmutation of spent nuclear fuel (SNF) may develop internal stresses resulting from forming operations including plastic deformation and welDing Techniques such as pair-production, activation and life-time analysis based on classical positron annihilation spectroscopy (PAS) have been used to characterize residual stresses in candidate structural materials subjected to cold-reduction, plastic deformation and welDing Since the PAS techniques can only provide qualitative evaluation of residual stress, calibration curves were developed to estimate the resultant residual stress as a function of PAS line-shape parameters. Since plastic deformation can lead to the generation of defects …
Changes In The Stress Tolerance Of Two Mojave Desert Perennial Shrubs After Eight Years Of Growth In Elevated Carbon Dioxide, Allison Louise Ebbets
Changes In The Stress Tolerance Of Two Mojave Desert Perennial Shrubs After Eight Years Of Growth In Elevated Carbon Dioxide, Allison Louise Ebbets
UNLV Retrospective Theses & Dissertations
Global climate change is a significant issue facing modern society. Potential changes include increased atmospheric CO2 concentrations, increased temperature, altered precipitation patterns, and increased nitrogen deposition. The Nevada Desert FACE (Free Air Carbon dioxide Enrichment) Facility (NDFF) examines the effects of increased atmospheric CO2 concentration in an arid ecosystem. The effects of elevated CO2 on plants include increased growth rates and stress tolerance. This study examined the mechanistic changes in drought tolerance of two dominant Mojave Desert shrubs ( Larrea tridentata and Ambrosia dumosa) grown in elevated (550 mumol mol-1) or ambient (380 mumol mol -1) CO2 concentrations. Previous studies …
Metallurgical Characterization And Residual Stress Measurements Of Target Structural Materials, Vikram Marthandam
Metallurgical Characterization And Residual Stress Measurements Of Target Structural Materials, Vikram Marthandam
UNLV Retrospective Theses & Dissertations
This investigation is focused on the evaluation of residual stresses in target structural materials due to plastic deformation and welding by using both destructive ring-core (RC) method and nondestructive techniques including positron annihilation spectroscopy (PAS), neutron diffraction (ND) and x-ray diffraction (XRD) methods. Materials tested were austenitic Type 304L SS and martensitic Alloys EP-823 and HT-9. Types of specimen tested include cold-worked (CW), three-point-bent and welded specimens consisting of similar and dissimilar materials. The CW specimens showed increased residual stresses with an increase in cold reduction level. Measurements made on the welded specimens revealed higher residual stresses close to the …
Residual Stress Measurements And Analysis By Destructive And Non-Destructive Techniques, Satish Babu Dronavalli
Residual Stress Measurements And Analysis By Destructive And Non-Destructive Techniques, Satish Babu Dronavalli
UNLV Retrospective Theses & Dissertations
This investigation is focused on the evaluation of residual stresses resulting from cold deformation and welding in candidate target structural materials such as martensitic Alloys EP-823 and HT-9, and austenitic Type 304L stainless steel (SS). Measurements of residual stresses were performed by both destructive and nondestructive techniques including ring-core (RC), neutron diffraction (ND) and positron annihilation spectroscopy (PAS). The results obtained by the PAS method indicate that the residual stresses in the cold-worked specimens were significantly enhanced with increased level of cold reduction. Residual stress measurements by the RC method on welded specimens consisting of similar materials revealed tensile stresses …
Lower Limb Bone Shape And Structure Among Populations Of Differing Lifestyles: Effects Of Biomechanical Stress And Inferences Of Activity, Michele Marcela Bleuze
Lower Limb Bone Shape And Structure Among Populations Of Differing Lifestyles: Effects Of Biomechanical Stress And Inferences Of Activity, Michele Marcela Bleuze
UNLV Retrospective Theses & Dissertations
It is known that activity-related stresses and mechanical loadings affect adult bone morphology. The purpose of this study is to examine how well presumed subsistence-related activities correlate with bone morphology; In addition, this study will investigate the degree to which sex differences can be explained by differences in mechanical loaDing If such differences in expression are apparent between males and females within a population, then it can be speculated that the sexes were participating in different activities---or at least in activities that yielded different mechanical loadings; Although there have been several biomechanical studies that have looked at the relationship between …
Stress Corrosion Cracking And Hydrogen Embrittlement Of Martensitic Alloy Ep -823, Mohammad Kamal Hossain
Stress Corrosion Cracking And Hydrogen Embrittlement Of Martensitic Alloy Ep -823, Mohammad Kamal Hossain
UNLV Retrospective Theses & Dissertations
This investigation is focused on the evaluation of stress corrosion cracking (SCC), localized corrosion, and hydrogen embrittlement (HE) susceptibility of martensitic Alloy EP-823 in neutral and acidic solutions at ambient and elevated temperatures. While no failures were observed in smooth specimens in the neutral solution, failures were noticed in the 90°C acidic solution at constant-load (CL) leading to a threshold stress (sigmath) of 102 ksi. The presence of a notch reduced the sigmath value to 91 ksi in a similar environment. The ductility (%El and %RA), time-to-failure (TTF), and true failure stress (sigmaf) were gradually reduced in both environments with …
Personal Epistemology: Implications For Stress In College Students, Robyn M Johnson
Personal Epistemology: Implications For Stress In College Students, Robyn M Johnson
UNLV Retrospective Theses & Dissertations
This research study investigated whether college students' epistemological beliefs (i.e. certain knowledge, simple knowledge, fixed ability, quick learning, and omniscient authority) could predict negative stressors and/or reactions to stress in their college experience. Based on responses to two self-assessment inventories and a demographic survey; analysis of the data suggests that over and above contributions from demographics (i.e. gender, ethnicity, age, and education level), certain dimensions of epistemological beliefs contributed significantly to the prediction of negative stress in college students. This suggests that it is essential for educators to provide opportunities for students' epistemological development; specifically, in the area of constructing …
Two Non-Specific Indicators Of Stress: Enamel Hypoplasia And Harris Lines, Marta Pilar Alfonso Durruty
Two Non-Specific Indicators Of Stress: Enamel Hypoplasia And Harris Lines, Marta Pilar Alfonso Durruty
UNLV Retrospective Theses & Dissertations
Harris lines (HL) and enamel hypoplasia (EH) are two non-specific indicators of stress, commonly used in the reconstruction of the health status in past and present populations. The aim of this study was to determine if there is a correlation between these two markers. To achieve this aim, a sample of 136 individuals from two archaeological sites (Az-71 and Az-l40) from northern Chile was analyzed. HL and EH showed no correlation in terms of presence absence at the individual level. In addition, HL and EH, by age of the individual at the time of the defect formation, showed a completely …
Prediction Of Performance Time On A Treadmill Stress Test Following A Bruce Protocol, Helena Nadine Boersma
Prediction Of Performance Time On A Treadmill Stress Test Following A Bruce Protocol, Helena Nadine Boersma
UNLV Retrospective Theses & Dissertations
The purpose of this study was to determine if screening tools from a self-reporting questionnaire, comprised of work-capacity questions, and physiological data, could be developed to predict treadmill test time when following a Bruce protocol. One hundred and eight subjects completed the questionnaire and performed treadmill tests. A stepwise regression analysis was used to develop equations from the research parameters established on the questionnaire, and resulted in two useful predictive equations, one for males and one for females. Results indicated 52 males and 33 females had actual treadmill times of six minutes or greater. The prediction equations predicted 59 males …
Precipitating And Prophylactic Factors Contributing To Posttraumatic Stress Disorder Symptomatology In Maltreated Children, Lisa Marie Linning
Precipitating And Prophylactic Factors Contributing To Posttraumatic Stress Disorder Symptomatology In Maltreated Children, Lisa Marie Linning
UNLV Retrospective Theses & Dissertations
This study examined mediating factors that lead to, or buffer against, development of posttraumatic stress disorder (PTSD) after child maltreatment. Fifty-five children aged 8--17 years voluntarily completed self-report questionnaires and a structured diagnostic interview. It was hypothesized that (1) chronicity and severity of abuse amplify PTSD risk when a child has limited support networks, ineffective coping, external locus of control, affect dysregulation, and a dysfunctional family; (2) key family and victim characteristics would help to ameliorate effects of traumatic abuse; (3) the combination of precipitating and prophylactic factors would determine the effectiveness of managing traumatic maltreatment. Results suggest that dysthymia, …
Coping Strategies And Stress Levels Of Parents Of Children With Autism, Tammy L Neil
Coping Strategies And Stress Levels Of Parents Of Children With Autism, Tammy L Neil
UNLV Retrospective Theses & Dissertations
The purpose of this study is to assess stress levels and coping strategies of parents with children with autism. The goal is to identify the resources and support systems which parents use for coping with their stress and to assess whether the support systems differ between mothers and fathers. This study will also investigate differences in coping strategies used by parents of children with autism and parents of typically developing children; Subjects in this study included thirty parents of children with autism, and thirty parents of typically developing children. All participants were recruited from the Eastern, Midwest, and Western part …
Post-Traumatic Stress Disorder: The Hidden Epidemic And Its Effect On Society, Donald Phelan Stewart
Post-Traumatic Stress Disorder: The Hidden Epidemic And Its Effect On Society, Donald Phelan Stewart
UNLV Retrospective Theses & Dissertations
Post Traumatic Stress Disorder, a debilitating and sometimes disabling mental disorder, is emerging as one that is costly to society from many perspectives. PTSD sufferers commonly experience an inability to function normally within the workplace or within their social and family relationships. The disorder triggers strong emotional responses, changes social interaction and precipitates primary and secondary deviant behavior. This work focuses on non war related civilian incidence of the disorder. It examines the causes, circumstances and processes leading to the onset of the disorder and explores societal reaction to PTSD sufferers. Central to the work are the individual case studies …
Thermal Stress Analysis Of Thermally Sprayed Coatings On A Spent Nuclear Fuel Waste Package, Michael Joseph Plinski
Thermal Stress Analysis Of Thermally Sprayed Coatings On A Spent Nuclear Fuel Waste Package, Michael Joseph Plinski
UNLV Retrospective Theses & Dissertations
The purpose of applying a thermal sprayed coating on a spent nuclear fuel waste package is to prevent moisture contacting the spent nuclear fuel for tens of thousands of years. This thesis studies some of the thermal effects that a coated waste package may experience. Residual stress from the thermal spray process is one of these effects and in this study two modeling methods are compared. Finally, a finite element analysis of the initial emplacement of the spent nuclear fuel in the waste package is used to determine if any spalling of the coating from the waste package will occur; …
Heat Shock Proteins As Indicators Of Environmental Stress, Arthur Louis Castle
Heat Shock Proteins As Indicators Of Environmental Stress, Arthur Louis Castle
UNLV Retrospective Theses & Dissertations
In order to determine whether heat shock proteins (HSP) can be used as indicators of environmental stress in the mammalian organism Peromyscus leucopus, three doses of each of two chemical stresses, cadmium chloride and 2,4,5-trichlorophenoxyacetic acid (2,4,5-T), were given intraperitoneally for 14 days. Proteins extracted from liver samples were compared by one-dimensional gel electrophoresis to liver protein samples from heat shocked and control animals. HSPs of 105,78, and 43 kDa were cadmium inducible. Non-heat shocked cadmium inducible proteins of 118, 55, and 47 kDa were seen. 2,4,5-T induced an increase in a 91 kDa protein. Low level cadmium induction of …
Experimental Verification Of Finite Element Analysis For Deep Denting Of Cylindrical Shells, Rajkumar Rajagopalan
Experimental Verification Of Finite Element Analysis For Deep Denting Of Cylindrical Shells, Rajkumar Rajagopalan
UNLV Retrospective Theses & Dissertations
This dissertation presents results from research in experimental and numerical studies related to deep denting of mild steel pipes. Two sets of large scale steel pipes having similar aspect ratios, diameter to thickness (D/t) of 64 and length to diameter (L/D) of 4.5 to 5 were tested in the laboratory and analyzed by nonlinear finite element method (FEA). The experiments were performed on a set of 12 inch diameter, 0.1875 inch thick, 60 inch long, and a set of 8 inch diameter, 0.125 inch thick, 36 inch long pipes using an MTS axial torsional testing equipment and Tinius Olsen universal …
Stress Study In Faulted Tunnel Models By Combined Photoelastic Measurements And Finite Element Analysis, Yuping Huang
Stress Study In Faulted Tunnel Models By Combined Photoelastic Measurements And Finite Element Analysis, Yuping Huang
UNLV Retrospective Theses & Dissertations
An investigation is performed to develop a proper technique for analyzing the stresses in and around three adjacent scaled tunnel models, along with the stress concentration factors resulting from the existence of a fault that penetrates two of the three tunnels, at an inclined angle; Photoelasticity and Finite Element method, are used in this investigation. The Photoelastic measurements are performed by using a plexiglass plane model. Concurrent simulations of the same plexiglass model are performed by the Finite Element analysis. The principal stress patterns are measured by both methods, and the stress concentration factors are calculated at predetermined points. Results …
Physiological Response Of Two Turfgrass Species To Increasing Drought And Salinity Stress Using A Line Source Gradient, Dorothy E Dean
Physiological Response Of Two Turfgrass Species To Increasing Drought And Salinity Stress Using A Line Source Gradient, Dorothy E Dean
UNLV Retrospective Theses & Dissertations
A line source gradient study was initiated to investigate the feasibility of using the saline aquifer, existing beneath the Las Vegas valley, as an alternative irrigation source for turfgrass. Results indicated that the aquifer could be used as a supplemental irrigation source, without any diminished turfgrass quality, if total water potentials {dollar}\rm(\Psi\sb{T}){dollar} were maintained above species specific thresholds, where {dollar}\rm\Psi\sb{T}{dollar} is defined as the sum of the matric {dollar}\rm(\Psi\sb{M}){dollar} and osmotic {dollar}\rm(\Psi\sb{\Pi}){dollar} potentials. The soil water potential components {dollar}\rm(\Psi\sb{M},\Psi\sb{\Pi}){dollar} were found to additively affect yield, evapotranspiration, turf color, percent cover, and turf temperature. Leaf xylem water potential, stomatal conductance, and …
The Stress Of Fathers During The Labor And Delivery Of Their Partner, Deann Robinson Brown
The Stress Of Fathers During The Labor And Delivery Of Their Partner, Deann Robinson Brown
UNLV Retrospective Theses & Dissertations
This descriptive, retrospective survey employed a questionnaire to determine what factors cause stress to expectant fathers during their partner's labor and delivery and how that stress is exhibited. Fathers of healthy newborns at two hospitals in Utah accompanying their partner in labor and delivery were asked to complete the questionnaire within 36 hours after the birth of their baby. The survey elicited responses from three different time periods during the labor and delivery: (1) the beginning of labor; (2) labor from the time of admission to the hospital and when labor reached its peak until delivery; and (3) during the …
Myceloid Cell Formation In Arthrobacter Globiformis During Osmotic Stress, Ganegodage Shyama Perera
Myceloid Cell Formation In Arthrobacter Globiformis During Osmotic Stress, Ganegodage Shyama Perera
UNLV Retrospective Theses & Dissertations
Arthrobacters exhibit a dimorphic growth cycle where exponential phase cells appear as irregular bacilli and stationary phase cells as cocci. Arthrobacter globiformis was found to form myceloids when subjected to osmotic stress. Addition of known osmoprotective compounds did not relieve this effect. Since myceloid formation may result from altered penicillin-binding proteins (PBPs), PBP profiles of stressed and unstressed A. globiformis were studied. Eight PBPs were identified, ranging in molecular mass from 91,000 to 30,000 daltons. Myceloids appeared to lack PBP 2a (84 kD) and PBP 2b (82 kD) in all growth conditions. The myceloids were 12-20 times more sensitive to …
Effects Of Estrogen And Progesterone On Tolerance To Thermal Stress, Kris Alan Lyon
Effects Of Estrogen And Progesterone On Tolerance To Thermal Stress, Kris Alan Lyon
UNLV Retrospective Theses & Dissertations
Analysis of variance showed that female Harlan Sprague-Dawley rats treated with E in combination with P (EP) had a significantly higher rectal temperature (Tre) than untreated control animals and those treated with E or P alone. In E treated rats, Tre was significantly higher than control animals and those treated with P; All treatment groups had a significantly lower tail skin temperature as compared to the control animals. The rise in Tre in E and EP treated rats did not appear to result from an increase in metabolism since the rates of oxygen consumption did not differ significantly with hormone …
Stress Management In Las Vegas Municipal Court, Robert Clinton Zangger
Stress Management In Las Vegas Municipal Court, Robert Clinton Zangger
UNLV Retrospective Theses & Dissertations
An analysis of the effectiveness of Las Vegas Municipal Court's stress management workshop was conducted. The State-Trait Anxiety Inventory was given to fifty one volunteers prior to and after a stress management workshop. Of the 51, seven participated in a four hour workshop given in two sessions. Those attending the workshop had elevated stress scores after the workshop. Exposure to the symptoms of stress without adequate follow-up on how to treat the symptoms may have led to the unexpected result. It is on the basis of these findings that future workshops concentrate on identifying stress related symptoms as well as …
The Relationship Between Stressor Rankings And Management Styles Of Nevada Elementary And Secondary Public School Principals (Leadership Style, Stress), Michael Sutton Robison
The Relationship Between Stressor Rankings And Management Styles Of Nevada Elementary And Secondary Public School Principals (Leadership Style, Stress), Michael Sutton Robison
UNLV Retrospective Theses & Dissertations
The purpose of this study was to determine what relationships existed between various stressor rankings selected from the Administrative Events Stress Inventory, and selected leadership styles as determined by the Leader Adaptability Style Inventory and exhibited by the elementary and secondary school administrators in the State of Nevada; The findings of the study were: (1) A majority of Nevada school principals were of the leadership style consisting of a High Task/High Relationship orientation. (2) There were no significant correlations between the four leadership styles as determined by the Leader Adaptability Style Inventory and selected job stressor events selected from the …
The Kinetic Family Drawings As An Indicator Of Marital Instability And Family Stress, Edward Henry Schacker
The Kinetic Family Drawings As An Indicator Of Marital Instability And Family Stress, Edward Henry Schacker
UNLV Retrospective Theses & Dissertations
Problem. Because of the implementation of public laws regarding the right of all handicapped children to a free and appropriate public education, school psychologists have experienced an increasing demand to provide accurate and timely psychoeducational assessment. In particular there is increased focus on the diagnosis of emotional disturbance and the need for the development and/or validation of instruments which can reliably measure this handicapping condition. It is also extremely advantageous to be able to determine whether the emotional disturbance is chronic or transitory so that appropriate educational programming can be developed. This study investigated one aspect of the Kinetic Family …