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The Effect Of 5-Aminolevulinic Acid Based Photodynamic Therapy And Photochemical Internalization Of Bleomycin On The F98 Rat Glioma Cell Line, Khishigzaya Kharkhuu
The Effect Of 5-Aminolevulinic Acid Based Photodynamic Therapy And Photochemical Internalization Of Bleomycin On The F98 Rat Glioma Cell Line, Khishigzaya Kharkhuu
UNLV Retrospective Theses & Dissertations
The F98 rat glioma cell line, a model for human malignant glioma, was used to investigate the efficacy of 5-aminolevulinic acid (ALA)-mediated photodynamic therapy (PDT) under varying light irradiation conditions. Cells in monolayer were pre-incubated in ALA for 4 hours prior to 635 nm light exposure. Using clonogenic survival assays, it was found that F98 glioma cells were sensitive to ALA-PDT: survival was inversely proportional to light fluence. As evidenced from the LD50 (4 J cm-2 at a fluence rate of 35 mW cm-2), ALA-PDT was found to be more effective in F98 cells compared to that found in another …
Effects Of Pavement Macrotexture On Pm(10) Emissions From Paved Roads, Swarup China
Effects Of Pavement Macrotexture On Pm(10) Emissions From Paved Roads, Swarup China
UNLV Retrospective Theses & Dissertations
This study compares two methods for measuring pavement macrotexture and investigates the influence of paved road macrotexture on paved road PM 10 emissions originating both from soil erosion and deposition, and from tire, brake and asphalt wear. Macrotexture was measured using the ASTM Sand patch method and the Digital Surface Roughness Meter (DSRM). PM 10 emissions were estimated using AP-42 sampling and measured with a Mini-PI-SWERL(TM); DSRM and sand patch mean texture depths (MTDs) were well-correlated. Silt-normalized ambient PM10 emissions variations were partially explained by pavement macrotexture. PM10 emissions experiments using controlled silt loadings showed good correlations with pavement macrotexture. …
The Effect Of Math Anxiety On Learning A Novel Math Task, Jeremy Adam Krause
The Effect Of Math Anxiety On Learning A Novel Math Task, Jeremy Adam Krause
UNLV Retrospective Theses & Dissertations
The focus of this experiment was to assess the effect of math anxiety on learning a novel math task (modular arithmetic). While participants that were low in math anxiety performed significantly better (in terms of reaction time) than participants that were in the medium and high math anxiety groups on repeated problems, the low math anxious participants did not perform differently than the medium and high math anxiety groups on unique problems. This indicates that the low math anxious participants were better able to learn the procedure of modular arithmetic but were not significantly different in their ability to learn …
The Effects Of Cryotherapy On Eccentric Peak Torque Recovery After An Intense Eccentric Exercise, Michelle Nicole Peluaga
The Effects Of Cryotherapy On Eccentric Peak Torque Recovery After An Intense Eccentric Exercise, Michelle Nicole Peluaga
UNLV Retrospective Theses & Dissertations
This study investigated the effects of a 45-minute cryotherapy application post-exercise repeated daily for 3-days on the recovery of the quadriceps after inducing DOMS. Results showed eccentric mean PT was greater at baseline than 24-hours after eccentric exercise. Knee AROM, joint line, 5cm, and 10cm girth measurements resulted in no differences. However, 15cm and 20cm sites revealed baseline values being lower than 48-hours; Tenderness at VMO post-treatment resulted in a difference with the initial application being lower than 24-hours. The 15cm site pre-exercise and post-treatment resulted in differences where baseline was lower than 24 and 48-hours. Post-exercise revealed the treated …
The Effects Of Exercise In The Rehabilitation Process Of Substance Abuse, Gabriela Vilarino Regino
The Effects Of Exercise In The Rehabilitation Process Of Substance Abuse, Gabriela Vilarino Regino
UNLV Retrospective Theses & Dissertations
Exercise may assist in the rehabilitation process by providing a way for the dependent individual to achieve a mild, pleasurable state that does not require the use of substances; Women between 18 and 43 years of age who were under supervision in a rehabilitation facility for substance abuse were randomly selected to be part of an exercise or a control group. They exercised three times a week for a total of two months. Subjects completed pre and post assessments of anxiety, depression, and readiness to change. They also completed pre and post assessments of resting heart rate, percent body fat, …
Modeling The Unsaturated Zone At The Area 5 Radioactive Waste Management Site: Effects Of Climate Change And Vegetation On Flow Conditions, Amanda Marie Brandt
Modeling The Unsaturated Zone At The Area 5 Radioactive Waste Management Site: Effects Of Climate Change And Vegetation On Flow Conditions, Amanda Marie Brandt
UNLV Retrospective Theses & Dissertations
This thesis tests a series of potential future climate scenarios and associated environmental conditions that could result in the reversal of the present upward hydraulic gradient in the vadose zone at the Area 5 Radioactive Waste Management Site (RWMS) by implementing a one-dimensional model developed using the HYDRUS 1-D numerical modeling package. The research is divided into two phases. Phase I simulates the system from the Pleistocene to Holocene transition (approximately 13,000 years ago) to the present and is tested by independently varying precipitation, evaporation and transpiration rates. The results provide initial conditions for subsequent modeling under Phase II, which …
Temperature And Silicon Effects On Tensile And Corrosion Behavior Of Chronium-Molybdenum Steel, Hanumantha Rao Chava
Temperature And Silicon Effects On Tensile And Corrosion Behavior Of Chronium-Molybdenum Steel, Hanumantha Rao Chava
UNLV Retrospective Theses & Dissertations
Martensitic P91 grade steels containing 0.48, 0.96, 1.28 and 1.77 weight percent (wt%) silicon (Si) have been tested for evaluation of their tensile properties at temperatures ranging from ambient to 550°C. The effect of activation using accelerator-driven electron beams on the room-temperature tensile properties of steels containing 0.48 and 1.28 wt% Si has also been investigated. The results indicate that all four heats of steel exhibited dynamic strain ageing at temperatures up to 400°C. The activated specimens showed enhanced tensile strength but reduced ductility with increasing activation time, indicating radiation hardening of the tested materials. The electrochemically-polarized specimens showed more …
The Effects Of Different Sport Mouth Guards On Respiration Rate And Tidal Volume At Sub-Maximal Exercise Level, Kevin Michael Finnegan
The Effects Of Different Sport Mouth Guards On Respiration Rate And Tidal Volume At Sub-Maximal Exercise Level, Kevin Michael Finnegan
UNLV Retrospective Theses & Dissertations
The problem directing this study was to determine differences between self-adapting sport mouthguards on respiratory rate and tidal volume during sub-maximal steady state exercise. The study was a within-subjects, repeated measures design. Fifteen male endurance trained subjects performed six sets of a 600 kpm workload for 10 min on a Monark cycle ergometer with five different mouthguard types (single sided, double sided, brain pad, gel or lip & mouth). Variables were analyzed by the ORCA metabolic system. The initial trial was a control trial with no mouthguard. The following five trials had five different mouthguard types used in a randomized …
The Effect Of Erosion Control Structures On The Distribution Of Selected Nutrients And Metals In The Sediments Of The Salt River, Arizona, Alan Christopher Williams
The Effect Of Erosion Control Structures On The Distribution Of Selected Nutrients And Metals In The Sediments Of The Salt River, Arizona, Alan Christopher Williams
UNLV Retrospective Theses & Dissertations
The Salt River travels through the urban areas of Maricopa County and its flows are fed primarily by treated wastewater, shallow groundwater, urban runoff, industrial effluent, agricultural runoff, and storm water runoff before merging with the Gila River and eventually the Colorado River. The population growth in Maricopa County has influenced the flows of the Salt River for more than a century. The past century has seen major flooding in the valley and the construction of erosion control structures has been part of an effort to reduce damages due to flood events. These structures affect the flow of sediment through …
Nitrate Ion Effects On Uranium Chemistry In The Tributylphosphate-Dodecane System, Amber Dawn Wright
Nitrate Ion Effects On Uranium Chemistry In The Tributylphosphate-Dodecane System, Amber Dawn Wright
UNLV Retrospective Theses & Dissertations
Understanding the role of nitrate in the speciation of actinides is important in order to determine the necessary data for extraction modeling of the UREX process. The focus of this project is on the fundamental chemistry of uranium (U) in the tributyl phosphate (TBP) extraction system, with emphasis on the effect of nitrate on actinyl speciation. Speciation calculations can be performed if stability and solubility constants for the chemical species formed under the examined conditions are known. The stability constant of the uranyl-TBP complex was evaluated under a variety of conditions. The variables were nitric acid, uranyl, total nitrate concentration, …
The Determinants And Effects Of Slot Servicescape Satisfaction In A Las Vegas Casino, Anthony Frederick Lucas
The Determinants And Effects Of Slot Servicescape Satisfaction In A Las Vegas Casino, Anthony Frederick Lucas
UNLV Retrospective Theses & Dissertations
Scales representing ambient conditions, ability to navigate the slot floor, cleanliness, interior decor and seating comfort all produce a significant effect on slot servicescape satisfaction. Scales representing slot servicescape satisfaction and gaming value produce significant effects on overall satisfaction with the slot experience. Collinearity conditions prevented the measurement of staff friendliness and service promptness on overall satisfaction. Both servicescape satisfaction and overall satisfaction produce significant effects on behavioral intention variables related to loyalty and desire to remain in the casino environment. Simultaneous multiple regression analysis was used to test all one-tailed hypotheses at the .10 alpha level (n = 195); …
The Effects Of Students' Asynchronous Online Discussions Of Conceptual Errors On Intentionally Flawed Teacher-Constructed Concept Maps, Magdalena Sas
The Effects Of Students' Asynchronous Online Discussions Of Conceptual Errors On Intentionally Flawed Teacher-Constructed Concept Maps, Magdalena Sas
UNLV Retrospective Theses & Dissertations
Research shows that online discussions are often unfocused and without providing much benefit to students' learning outcomes. One of the reasons behind this phenomenon is the lack of or inadequate scaffolding or guidance provided to students when participating on asynchronous discussion boards. The collaborative misconception mapping strategy is a tool that was designed to mediate cognitive and metacognitive processes via feedback provided by peers and a teacher-created concept map that contains intentional conceptual errors; This study evaluated the effects of collaborative misconception mapping as compared with those of a traditional online discussion activity, where students post responses to discussion questions. …
Effects Of Metallurgical And Environmental Variables On The Performance Of Alloy 718 For Heat Exchanger Applications, Anand Venkatesh
Effects Of Metallurgical And Environmental Variables On The Performance Of Alloy 718 For Heat Exchanger Applications, Anand Venkatesh
UNLV Retrospective Theses & Dissertations
Austenitic Alloy 718 was extensively investigated, evaluating its tensile properties, crack-growth-rate (CGR), impact resistance, and resistance to stress-corrosion-cracking (SCC) and localized corrosion. The tensile data enabled a development of mechanisms on dynamic strain aging (DSA) and yield strength anomaly (YSA). The magnitudes of dislocation density, activation energy and work-hardening index, related to the DSA phenomenon, were estimated using different analytical approaches. The occurrence of YSA was verified based on transmission electron microscopic evaluations. The steady state CGR followed the Paris equation, showing a linear relationship. Alloy 718 exhibited a respectable impact resistance irrespective of the testing temperature. The SCC susceptibility …
The Effects Of Feedback Protocol And Learning Environment Perceptions On Self -Regulated Learning, Kevin David Biesinger
The Effects Of Feedback Protocol And Learning Environment Perceptions On Self -Regulated Learning, Kevin David Biesinger
UNLV Retrospective Theses & Dissertations
The current research investigated the effects of differing feedback protocols in a multimedia learning environment to determine if changes would occur over time in goal orientation, self-regulation, self-efficacy or achievement. Subjects from an traditional undergraduate chemistry course were assigned to either a norm-referenced or self-referenced feedback group. Goal orientation and self-efficacy were measured via self-report surveys pre-post instruction, self-regulation was measured as the cumulative number of times each subject opened a worked example/self-explanation prompt while engaged in weekly web-based quizzes, and achievement was measured using final semester course grades. Perceptions of the learning environment were also probed as a potential …
Modeling Natural Resource Scarcity And Poverty Effects On Fertility In Honduras, Nepal, And Tanzania, Ayoub Shaban Ayoub
Modeling Natural Resource Scarcity And Poverty Effects On Fertility In Honduras, Nepal, And Tanzania, Ayoub Shaban Ayoub
UNLV Retrospective Theses & Dissertations
This dissertation examines whether the vicious circle theory applies in three developing countries characterized by high population growth. According to the vicious circle theory, natural resource scarcity coupled with poverty leads to population growth via positive effects on fertility particularly in rural areas of developing countries. Population growth then leads to a further increase in natural resource scarcity, creating a "feedback loop." This is the first study to use micro-level data to test and control for endogeneity using a two-stage Probit model (IVPROBIT). The existing literature has largely failed to address endogeneity in the relationship between natural resource scarcity and …
The Effects Of Electromagnetic Fields On The Detection Of Mercury And Radionuclides, Yogendra M Panta
The Effects Of Electromagnetic Fields On The Detection Of Mercury And Radionuclides, Yogendra M Panta
UNLV Retrospective Theses & Dissertations
Mercury and many radionuclides are extremely toxic, and their monitoring and detection are of importance for human health and environmental protection. This dissertation focuses on the detection of mercury (II) ions and radionuclides including uranium (234U and 238U), plutonium (239Pu), and americium (241Am) in aqueous solutions under the effects of electromagnetic fields. The stripping electrochemical method has been widely used to detect mercury (II) ions in aqueous solutions. To enhance the detection sensitivity of the conventional electrochemical method, mechanically stirring the solution is usually performed to enhance the rate of the ionic mass transport. Instead of mechanically stirring the solution; …
The Effects Of Mushroom Body Lobe Disruption On Learning And Memory, Brian S Dunkelberger
The Effects Of Mushroom Body Lobe Disruption On Learning And Memory, Brian S Dunkelberger
UNLV Retrospective Theses & Dissertations
Animal models have been used for centuries to study learning and memory in simple systems with many applications to humans (Chapter 1). The fruit fly Drosophila melanogaster has added greatly to our current understanding of learning and memory and its underlying biology (Chapter 2). The research described here focuses on the relationship between learning and memory and the brain using three mutant strains of flies: mushroom body miniature B (mbmB), small mushroom bodies (smu), and mushroom bodies reduced (mbr). Mushroom bodies are paired neuronal structures found in most invertebrate brains involved in learning and memory consolidation. All three mutations studied …
The Effects Of Automated Essay Scoring As A High School Classroom Intervention, Kathie L Frost
The Effects Of Automated Essay Scoring As A High School Classroom Intervention, Kathie L Frost
UNLV Retrospective Theses & Dissertations
This quasi-experimental, mixed methods study investigated whether students writing development and proficiency, in combination with teacher-led instruction, are significantly affected by the use of an automated essay scoring (AES) system. The ninth grade standard and honors English students were divided into control and treatment groups at a large, urban high school. Student writing was examined for any changes in proficiency, measured by human- and AES-scored holistic measures. A developmental writing index was used to analyze the rate of change in pre- and post-essays. The AES system was further researched by comparing the treatment and control groups' trait score categories. Finally, …
Effects Of Elevated Carbon Dioxide On Soil Microbial Communities Of The Mojave Desert, Linh M. P Nguyen
Effects Of Elevated Carbon Dioxide On Soil Microbial Communities Of The Mojave Desert, Linh M. P Nguyen
UNLV Retrospective Theses & Dissertations
The objective of this study is to determine soil microbial community structure in the framework of increased atmospheric carbon availability associated with global change. Since arid ecosystems make up a considerable fraction of our biosphere, their response to global change will be of significance. Further, implication for plant and ecosystems productivity in arid environments may be linked to changes in diversity among microbial communities, since the cycling of essential elements in the soil is often mediated by microbes. The following are three sets of experiments designed to examine the changes in microbial diversity associated with a global change factor, an …
Complexation And Electrode Effects On The Electrochemical Behavior Of The Cerium(Iv)/Cerium(Iii) Redox Couple, Sandra Elias Elkouz
Complexation And Electrode Effects On The Electrochemical Behavior Of The Cerium(Iv)/Cerium(Iii) Redox Couple, Sandra Elias Elkouz
UNLV Retrospective Theses & Dissertations
The electrochemistry of the Ce(IV)/Ce(III) redox couple was investigated as a function of working electrode composition and solution environment. Optimum redox couple resolution in aqueous sulfuric acid was achieved at an acid concentration of 0.1 M. A decline in redox couple resolution and reversibility was observed as acid concentration was increased to 2.0 M. The influence of pH was illustrated using sulfate solutions of increasing pH and constant ionic strength. Results indicated that a pH greater than 2 was detrimental to redox couple resolution. The glassy carbon electrode provided the widest potential window and was least affected by changes in …
It's Just A Stage I'M Going Through: The Rhetorical Effects Of Musical Theater, Thomas A Moilanen
It's Just A Stage I'M Going Through: The Rhetorical Effects Of Musical Theater, Thomas A Moilanen
UNLV Retrospective Theses & Dissertations
Human communication is often thought of in rather limited terms, such as rhetoric or media effects or interpersonal exchanges. While many sub-groups lurk beneath these broad categorical trench coats, forms of artistic expression such as music, theater and humor find themselves in other intellectual clothing; yet, it is undeniable that most---if not all---human endeavors can be viewed through a communicative lens. Other disciplines are obviously worthy in their own right and contain enough distinct characteristics to keep scholars from exploring additional contexts, but why limit the study of music to the music department? Or the study of Literature to the …
Weblog Effects On Social Capital, Seyed Mohammad Reza Vaezi
Weblog Effects On Social Capital, Seyed Mohammad Reza Vaezi
UNLV Retrospective Theses & Dissertations
Weblog is the newest and clearly one of the most influential computer mediated communication (CMC) tools. Growing body of literature about the weblog effects on education, marketing, journalism, and human resource management is a sign of importance and significant effects of weblogs. This rapidly growing communication tool is expected to have significant impact on the work life of the individual and organization. However, there is little research evidence as to the nature and extent of this impact. Using a sample of 326, this research examines the effects of weblogs on social capital and its components: social connections, trust, and reciprocity. …
Estimating The Effects Of Casino Marketing Activities On Slot Business Volume: A Model For Leisure Services Businesses, Lisa Birtciel Young
Estimating The Effects Of Casino Marketing Activities On Slot Business Volume: A Model For Leisure Services Businesses, Lisa Birtciel Young
UNLV Retrospective Theses & Dissertations
This study researched the effect of marketing promotions on gaming volume (i.e., coin-in). Specifically, this study attempted (1) to gain an understanding of the relationship between specific marketing promotions (slot tournaments, special events, product prize drawings, and no marketing promotions) and gaming volume; and (2) to estimate the magnitude of incremental revenue for each type of promotion. A conceptual model was proposed to examine the effect of the different types of marketing promotions on gaming volume, including two other variables (holidays and day-of-the-week) previously found to influence gaming volume; Secondary data were collected from a Las Vegas Strip property for …
Effects Of Music Therapy On Prosocial Behavior Of Students With Autism And Developmental Disabilities, Catherine L De Mers
Effects Of Music Therapy On Prosocial Behavior Of Students With Autism And Developmental Disabilities, Catherine L De Mers
UNLV Retrospective Theses & Dissertations
This research study employed a multiple baseline across participants design to investigate the effects of music therapy intervention on hitting, screaming, and asking of three children with autism and/or developmental disabilities. Behaviors were observed and recorded during 10-minute free-play sessions both during baseline and immediately after music therapy sessions during intervention. Interobserver agreement and procedural fidelity data were collected. Music therapy sessions were modeled on literature pertaining to music therapy with children with autism. In addition, social validity surveys were collected to answer research questions pertaining to the social validity of music therapy as an intervention; Findings indicate that music …
The Effect Of Temperature On Development And Behavior Of Relict Leopard Frog Tadpoles (Rana Onca), Jeffrey Abraham Goldstein
The Effect Of Temperature On Development And Behavior Of Relict Leopard Frog Tadpoles (Rana Onca), Jeffrey Abraham Goldstein
UNLV Retrospective Theses & Dissertations
Relict Leopard frogs (Rana onca) are found in thermal springs with water temperatures in excess of 30°C at the source but it's unknown whether tadpoles require reintroduction sites with specific thermal conditions for development. Tadpole survivorship at 20, 25 and 30°C was 84, 93.8, and 66%, respectively, while none survived at 35°C. Time to metamorphosis was significantly shorter for 25°C acclimation group (62+/-8 days) followed by the 30° (106+/-51 days) and 20°C (260+/-47 days) acclimation groups. Development was arrested in the 15°C acclimated group and survivorship declined to 63.8% after 191 days. However, 80% of the surviving larvae completed metamorphosis …
The Multiple Effects Of A Showroom On Casino Outlets In Las Vegas, Dongnam Kang
The Multiple Effects Of A Showroom On Casino Outlets In Las Vegas, Dongnam Kang
UNLV Retrospective Theses & Dissertations
In the competitive casino market of Las Vegas, casino operators make efforts to lure more visitors to their properties by offering various live entertainment shows that competitors do not offer. The reviewed literature revealed that showrooms appeared to attract people to the casino floor and, consequently, had significant impact on driving additional casino revenues. However, the literature did not reveal actual evidence that showrooms, which require huge investments and operating costs, actually generate additional revenues to casino hotels. Therefore, the purpose of this research is to investigate the indirect impacts of shows offered in a hotel casino by examining the …
Evaluation And Modeling Of The Effect Of Midblock Pedestrian Crossings On Arterial Traffic, Naveen Kumar Veeramisti
Evaluation And Modeling Of The Effect Of Midblock Pedestrian Crossings On Arterial Traffic, Naveen Kumar Veeramisti
UNLV Retrospective Theses & Dissertations
Unsignalized midblock pedestrian crossings are one of the critical components of arterial streets designed to provide for safer crossing locations for pedestrians. These crossings are often placed between signalized intersections that are far apart. However when arterial segments with such crossings are being analyzed or designed, the effect of the crossings was not normally taken into consideration. This is primarily due to the inability of current traffic software in modeling these locations; The objective of this study was to evaluate the effect of midblock pedestrian crossings on the measures of effectiveness of arterial traffic flow using a computer simulation model. …
Acculturation Effects On Culture And Conflict Style, Mae-Li Amick Allison
Acculturation Effects On Culture And Conflict Style, Mae-Li Amick Allison
UNLV Retrospective Theses & Dissertations
In light of globalization, it is ever more valuable to understand how culture influences the way people manage conflict. Opportunities for individuals from varied cultural backgrounds to interact, and therefore conflict, are inherently greater because the technologies, economies, and livelihoods of people of many countries are increasingly interdependent. The purpose of this study was to examine factors influencing people's individualistic-collectivistic culture tendencies and conflict styles, and investigate acculturation as a moderating factor between individualism-collectivism and conflict style among foreign nationals living within the United States. In addition to acculturation, variables that could affect acculturation were also measured, including media use, …
The Effect Of Erosion Control Structures On The Distribution Of Selected Nutrients And Metals In The Sediments Of The Las Vegas Wash, Tracy Marie Boettcher
The Effect Of Erosion Control Structures On The Distribution Of Selected Nutrients And Metals In The Sediments Of The Las Vegas Wash, Tracy Marie Boettcher
UNLV Retrospective Theses & Dissertations
The Las Vegas Wash (Wash) channels the Las Vegas Valley's (Valley) treated wastewater, shallow groundwater, urban runoff, and stormwater runoff before terminating in Lake Mead at Las Vegas Bay. The population increase in the Valley has caused a dramatic increase in the flow of the Wash due to urbanization and increased wastewater effluent. Erosion control structures have been constructed to reduce erosion. These structures affect the flow of sediment through the Wash and might affect the distribution of potential contaminants in a way that can negatively impact plant and animal life; The chemical constituents examined in this study are arsenic, …
The Effect Of Prophylactic Ankle Taping On Valgus Knee Joint Moment During A Side Step Cut-Maneuver, Anthony John House
The Effect Of Prophylactic Ankle Taping On Valgus Knee Joint Moment During A Side Step Cut-Maneuver, Anthony John House
UNLV Retrospective Theses & Dissertations
Limited research evaluating the influence of prophylactic ankle taping on the lower extremity kinetic chain is available. Ankle and knee injury have been documented during quick deceleration and change in direction while running. Anecdotally, clinicians and researchers suggest that the application of prophylactic ankle taping to limit ankle movement does not translate pathogenic forces to the proximal joints. The purpose was to examine the effects of prophylactic ankle taping on valgus/varus joint moment at the knee during the side step cut-maneuver. Results indicate no significant difference (p-value=.60) between valgus/varus knee joint moment between un-taped and taped conditions; -0.37+/-.5 Nm/kg and …