Matching Items (195)
Description
Asperger's syndrome is a high-functioning subset of Autism Spectrum Disorders (ASD). Diagnosed patients often lack refined social skills but possess a normal level of cognitive skills without delay in language development. These deficient social skills can impact the ability to find and maintain a job, which can be burdensome for all individuals involved in the patient's life. Although the causes of this condition are largely unknown, a wide variety of social and cognitive therapies have been used to reduce symptom severity, one of which is Mindfulness-Based Stress Reduction (MBSR). Mindfulness is the act of being aware on purpose to whatever is being experienced in the present moment with non-judgment and receptivity. MBSR has been used to bring greater awareness to sensations, thoughts and emotions with the result being reduced reactivity and increased purposeful responsiveness. It is therefore the aim of this study to address the use of an 8-week Mindfulness-Based Stress Reduction in adolescents with clinical Asperger's Syndrome to reduce reactive tendencies. This study will utilize a randomized control group of waitlisted participants given MBSR informational material and a practicing MBSR group. Post-MBSR Parent Global Impressions-III (PGI-III) and Social Responsiveness Scale scores are hypothesized to be improved in MBSR group and unaffected in the control for behavioral markers with no change in core autistic symptoms. Daily average cortisol response is also expected to decrease in the experimental group with unaffected levels in the control.
ContributorsBrzezinski, Molly Alexandra (Author) / Smith, Brian (Thesis director) / Sebren, Ann (Committee member) / School of Music (Contributor) / School of Molecular Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
Description
The mammalian olfactory system is commonly studied by using the mouse as a model system. Odor habituation is used to investigate odor perception and learning processes. Most previous experimental preparations have been tedious, requiring a researcher to manually change odorants, record investigation time and duration at each odorant, or physical alteration on the mice to enable video tracking. These limitations were overcame by creating an odorized hole-board to allow for systematic and automatic recording of olfactory behavior in mice. A cohort of five male mice were utilized in these experiments and the responses to the odor of strawberries, a diet staple of wile mice, were examined. Experiment 1 showed that free-feeding mice exhibit a preference to locations with strawberry (over control locations), even when these locations can only be identified using olfaction. This preference habituates within a trial but not across days. Experiment 2 showed that strawberry odor without reward causes habituation or extinction to the odor both within trials and across days. From these experiments, it can be concluded that mice innately explore strawberry odor and this can be exploited to the study odor habituation using an odorized hole-board.
ContributorsMa, Jason (Author) / Smith, Brian (Thesis director) / Gerkin, Richard (Committee member) / Oddo, Salvatore (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
Animals must learn to ignore stimuli that are irrelevant to survival, a process referred to as latent inhibition. The Amtyr1 gene has been shown through quantitative trait loci mapping to be linked to strong latent inhibition in honey bees. Here we implicate this G-protein coupled receptor for the biogenic amine tyramine as an important factor underlying this form of learning in honey bees. We show that dsRNA targeted to disrupt the tyramine receptors, specifically affects latent inhibition but not excitatory associative conditioning. Our results therefore identify a distinct reinforcement pathway for latent inhibition in insects.
ContributorsPetersen, Mary Margaret (Author) / Smith, Brian (Thesis director) / Wang, Ying (Committee member) / Sinakevitch, Irina (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
The fence between the US and Mexico had been and continues to be a controversial topic in both the U.S., Mexico and around the world. This study will look at the negative externalities related to the environment, society, and economy of the current fence on the border. The central question behind the thesis is whether or not the fence has a direct impact on the ecosystem and people around it.
ContributorsHoyt, Stephanie Alexis (Author) / Schoon, Michael (Thesis director) / Breetz, Hanna (Committee member) / School of Sustainability (Contributor) / School of Politics and Global Studies (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
In Apis mellifera, gustatory responsiveness to sucrose is a good indicator of learning ability \u2014 in that individuals with high sucrose responsiveness will typically form faster, longer-lasting associations with conditioned stimulus than individuals with a low sucrose responsiveness. The purpose of this study was to determine whether experience with olfactory conditioning had lasting effects on gustatory responsiveness. Groups were placed in an environment that would facilitate association of an odor to a sucrose reward, tested for retention, then tested for gustatory responsiveness. Control groups underwent the same testing schedule, but were not exposed to odor in the first environment. There was no significant difference in gustatory responsiveness between the two groups. Mann-Whitney tests were used to analyze the results, and though the mean GRS score was lower among the treatment group there was no significant trend, possibly due to small sample sizes.
ContributorsSeemann, J. H. (Author) / Amdam, Gro (Thesis director) / Smith, Brian (Committee member) / Barrett, The Honors College (Contributor)
Created2016-05
Description
Solar energy has become one of the most popular renewable energy in human’s life because of its abundance and environment friendliness. To achieve high solar energy conversion efficiency, it usually requires surfaces to absorb selectivity within one spectral range of interest and reflect strongly over the rest of the spectrum. An economic method is always desired to fabricate spectrally selective surfaces with improved energy conversion efficiency. Colloidal lithography is a recently emerged way of nanofabrication, which has advantages of low-cost and easy operation.
In this thesis, aluminum metasurface structures are proposed based on colloidal lithography method. High Frequency Structure Simulator is used to numerically study optical properties and design the aluminum metasurfaces with selective absorption. Simulation results show that proposed aluminum metasurface structure on aluminum oxide thin film and aluminum substrate has a major reflectance dip, whose wavelength is tunable within the near-infrared and visible spectrum with metasurface size. As the metasurface is opaque due to aluminum film, it indicates strong wavelength-selective optical absorption, which is due to the magnetic resonance between the top metasurface and bottom Al film within the aluminum oxide layer.
The proposed sample is fabricated based on colloidal lithography method. Monolayer polystyrene particles of 500 nm are successfully prepared and transferred onto silicon substrate. Scanning electron microscope is used to check the surface topography. Aluminum thin film with 20-nm or 50-nm thickness is then deposited on the sample. After monolayer particles are removed, optical properties of samples are measured by micro-scale optical reflectance and transmittance microscope. Measured and simulated reflectance of these samples do not have frequency selective properties and is not sensitive to defects. The next step is to fabricate the Al metasurface on Al_2 O_3 and Al films to experimentally demonstrate the selective absorption predicted from the numerical simulation.
In this thesis, aluminum metasurface structures are proposed based on colloidal lithography method. High Frequency Structure Simulator is used to numerically study optical properties and design the aluminum metasurfaces with selective absorption. Simulation results show that proposed aluminum metasurface structure on aluminum oxide thin film and aluminum substrate has a major reflectance dip, whose wavelength is tunable within the near-infrared and visible spectrum with metasurface size. As the metasurface is opaque due to aluminum film, it indicates strong wavelength-selective optical absorption, which is due to the magnetic resonance between the top metasurface and bottom Al film within the aluminum oxide layer.
The proposed sample is fabricated based on colloidal lithography method. Monolayer polystyrene particles of 500 nm are successfully prepared and transferred onto silicon substrate. Scanning electron microscope is used to check the surface topography. Aluminum thin film with 20-nm or 50-nm thickness is then deposited on the sample. After monolayer particles are removed, optical properties of samples are measured by micro-scale optical reflectance and transmittance microscope. Measured and simulated reflectance of these samples do not have frequency selective properties and is not sensitive to defects. The next step is to fabricate the Al metasurface on Al_2 O_3 and Al films to experimentally demonstrate the selective absorption predicted from the numerical simulation.
ContributorsGuan, Chuyun (Author) / Wang, Liping (Thesis advisor) / Azeredo, Bruno (Committee member) / Wang, Robert (Committee member) / Arizona State University (Publisher)
Created2019
Description
Biogas’s potential as a renewable fuel source has been an area of increased research in recent years. One issue preventing wide-spread use of biogas as a fuel is the trace amounts of impurities that damage fuel-burning equipment by depositing silicon, sulfur, calcium and other elements on their surface. This study aims to analyze the effects of a high concentration of L4 linear siloxane on solid oxide fuel cell performance until failure occurs. L4 siloxane has not been extensively researched previously, and this investigation aims to provide new data to support similar, though slower, degradation compared to D4, D5 and other siloxanes in solid oxide fuel cells. The experiments were conducted inside a furnace heated to 800℃ with an Ni-YSZ-supported (Nickel-yttria-stabilized zirconia) fuel cell. A fuel source with a flow rate of 20 mL/min of hydrogen gas, 10 mL/min of nitrogen gas and 0.15 mL/min of L4 siloxane was used. Air was supplied to the cathode. The effects of siloxane deposition on cell voltage and power density degradation and resistance increase were studied by using techniques like the current-voltage method, electrochemical impedance spectroscopy, and gas chromatography. The results of the experiment after reduction show roughly constant degradation of 8.35 mV/hr, followed after approximately 8 hours by an increasing degradation until cell failure of 130.45 mV/hr. The initial degradation and stagnation match previous research in siloxane deposition on SOFCs, but the sharp decline to failure does not. A mechanism for solid oxide fuel cell failure is proposed based on the data.
ContributorsRiley, Derall M. (Author) / Milcarek, Ryan J (Thesis advisor) / Wang, Liping (Committee member) / Phelan, Patrick E (Committee member) / Arizona State University (Publisher)
Created2021
Description
The thermal conductivity of cadmium sulfide (CdS) colloidal nanocrystals (NCs) and magic-sized clusters (MSCs) have been investigated in this work. It is well documented in the literature that the thermal conductivity of colloidal nanocrystal assemblies decreases as diameter decreases. However, the extrapolation of this size dependence does not apply to magic-sized clusters. Magic-sized clusters have an anomalously high thermal conductivity relative to the extrapolated size-dependence trend line for the colloidal nanocrystals. This anomalously high thermal conductivity could probably result from the monodispersity of magic-sized clusters. To support this conjecture, a method of deliberately eliminating the monodispersity of MSCs by mixing them with colloidal nanocrystals was performed. Experiment results showed that mixtures of nanocrystals and MSCs have a lower thermal conductivity that falls approximately on the extrapolated trendline for colloidal nanocrystal thermal conductivity as a function of size.
ContributorsSun, Ming-Hsien (Author) / Wang, Robert (Thesis advisor) / Rykaczewski, Konrad (Committee member) / Wang, Liping (Committee member) / Arizona State University (Publisher)
Created2022
Description
Windows are one of the most significant locations of heat transfer through a building envelope. In warm climates, it is important that heat gain through windows is minimized. Heat transfer through a window glazing occurs by all major forms of heat transfer (convection, conduction, and radiation). Convection and conduction effects can be limited by manipulating the thermal properties of a window’s construction. However, radiation heat transfer into a building will always occur if a window glazing is visibly transparent. In an effort to reduce heat gain through the building envelope, a window glazing can be designed with spectrally selective properties. These spectrally selective glazings would possess high reflectivity in the near-infrared (NIR) regime (to prevent solar heat gain) and high emissivity in the atmospheric window, 8-13μm (to take advantage of the radiative sky cooling effect). The objective of this thesis is to provide a comprehensive study of the thermal performance of a visibly transparent, high-emissivity glass window. This research proposes a window constructed by coating soda lime glass in a dual layer consisting of Indium Tin Oxide (ITO) and Polyvinyl Fluoride (PVF) film. The optical properties of this experimental glazing were measured and demonstrated high reflectivity in the NIR regime and high emissivity in the atmospheric window. Outdoor field tests were performed to experimentally evaluate the glazing’s thermal performance. The thermal performance was assessed by utilizing an experimental setup intended to mimic a building with a skylight. The proposed glazing experimentally demonstrated reduced indoor air temperatures compared to bare glass, ITO coated glass, and PVF coated glass. A theoretical heat transfer model was developed to validate the experimental results. The results of the theoretical and experimental models showed good agreement. On average, the theoretical model demonstrated 0.44% percent error during the daytime and 0.52% percent error during the nighttime when compared to the experimentally measured temperature values.
ContributorsTrujillo, Antonio Jose (Author) / Phelan, Patrick (Thesis advisor) / Wang, Liping (Thesis advisor) / Rykaczewski, Konrad (Committee member) / Arizona State University (Publisher)
Created2022
Description
ABSTRACT Over the past several decades, the dilemma of free-roaming horses in the U.S. has proven to be one of the most divisive issues in management of public lands. According to federal land management agencies, without population regulation, horses can increase at the rate of 15-20% a year on arid rangelands with inadequate numbers of natural, large predators. Horses compete for valuable forage and water resources alongside cattle and native wildlife in delicate riparian areas highly susceptible to the negative ecological effects of soil compaction and overgrazing. Most U.S. management policies, therefore, call for increased removal of free-roaming horses as they are categorized as “un-authorized livestock” or "non-native" species. Wild horse advocates, however, continue to petition for improvement in animal welfare and expansion of the horses’ territory. With heightened social conflict spurred by animal rights and ecological concerns, not to mention the often-stark differences over what really “belongs” on the landscape, the success of appropriate management strategies hinges on managing agencies’ preparedness and ability to respond in a timely and inclusive manner. A critical element of the management context is the public’s views toward the wild horse and the science used to manage them. Synthesizing the vast literature in the history and philosophy of wildlife management in the American West, and utilizing an ethnographic and case study approach, my research examines the range of stakeholder concerns and analyzes the factors that have led to the disconnect between public values of wild horses and public policy for the management of the federally protected free-roaming horses in Arizona’s Apache-Sitgreaves National Forests.
ContributorsMurphree, Julie Joan (Author) / Minteer, Ben A. (Thesis advisor) / Schoon, Michael (Thesis advisor) / Bradshaw, Karen (Committee member) / Chew, Matthew (Committee member) / Arizona State University (Publisher)
Created2022