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We examined the evolutionary morphological responses of Drosophila melanogaster that had evolved at constant cold (16°), constant hot (25°C), and fluctuating (16° and 25°C). Flies that were exposed to the constant low mean temperature developed larger thorax, wing, and cell sizes than those exposed to constant high mean temperatures. Males and females both responded similarly to thermal treatments in average wing and cell size. The resulting cell area for a given wing size in thermal fluctuating populations remains unclear and remains a subject for future research.
ContributorsAdrian, Gregory John (Author) / Angilletta, Michael (Thesis director) / Harrison, Jon (Committee member) / Rusch, Travis (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor)
Created2015-05
Description
Urbanization rapidly alters the environment, leading to a decrease in biodiversity in urban areas. A challenge associated with urbanized areas is the increased heat caused by the urban heat island effect. Heat may have an important impact on arthropods particularly due to their status as ectotherms. Animal behavior reveals how individuals interact with their environment. A behavioral syndrome describes consistent individual differences in behaviors that are correlated across different behavioral contexts or situations. Understanding the Western Black Widow's behavioral responses to the urban heat island effect has important implications for the control of a pest species. In this study, the relationship between rising urban temperatures and voracity, web-building, and cannibalism behaviors of juvenile Western Black Widows was examined. Spiders raised in the urban temperature treatment were predicted to have more aggressive behavioral syndromes, characterized by shorter latencies to forage, greater web-building activity, and shorter latencies to cannibalize as compared to spiders raised in rural or intermediate temperature treatments. A correlation between the latency to attack the first fly and second fly was found, however there were no other correlations evidencing a behavioral syndrome. Temperature was found to affect foraging, web-building, and cannibalism behaviors where spiders in urban areas demonstrated increased activity in all behavioral contexts. The possession of behavioral plasticity rather than a behavioral syndrome is likely what allows Black Widows to be successful urban pests.
ContributorsGarver, Emily Elizabeth (Author) / Johnson, James Chadwick (Thesis director) / Foltz-Sweat, Jennifer (Committee member) / Kitchen, Kathryn (Committee member) / School of Mathematical and Natural Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
Aedes aegypti are vectors for common arthropod-borne-diseases (arboviruses) such as Zika, yellow fever, dengue, and chikungunya, which are of significant public health concern. The management of vectors is critical to mitigating the incidence, reemergence, and expansion of these diseases. Vector control has been complicated by the emergence of insecticide resistance within vectors, which threatens the effectiveness of control efforts. Furthermore, vector management is also complicated by the interaction between insecticide susceptibility and abiotic factors, such as temperature. While it is well-documented that environmental factors affect insecticide susceptibility, it is poorly understood how insecticide resistant vectors with different genetic backgrounds respond to insecticides at different temperatures. This study aims to establish the relationship between deltamethrin susceptibility at varying temperatures across Ae. aegypti lines that differ in their susceptibility due to knockdown resistance (kdr) mechanism. This was done through exposures using the “WHO tube test method” using simulated climate environments (22°C, 27 °C, and 32 °C) on mosquitoes of varying resistance at 1016 and homozygous resistance at 1534. This experiment is still ongoing. This study found that IICC was the most resistant genotype, VVCC the least resistant, and VICC and intermediate. There was found to be no statistically significant relationship between temperature and insecticide susceptibility across kdr genotypes.
ContributorsAin, Joshua (Author) / Paaijmans, Krijn (Thesis director) / Huijben, Silvie (Committee member) / Jensen, Brook (Committee member) / Kalmouni, Joshua (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor)
Created2023-05
Description
Despite its well-documented preference for much more humid climates, the yellow fever mosquito, or Aedes aegypti, has inhabited Arizona since 1951. Their presence is of great concern as they can transmit many deadly diseases, including yellow fever, chikungunya, Zika, and dengue fever, putting the residents of the Phoenix Metropolitan Area at risk. Maricopa County Vector Control has made an extensive effort to reduce this risk mainly through the act of fogging insecticides during the night in areas where mosquito numbers exceed a threshold. However, given the well-known temperature-toxicity relationships in insect species, fogging at night may be less or more effective —depending on the relationship— due to the colder temperatures at these times. Additionally, insecticide resistance testing has always been performed at temperatures not usually experienced during fogging, adding to the uncertainty on how useful those test outcomes are. This study took the first steps in determining the effects of temperature on the toxicity of a commonly used insecticide, deltamethrin, on Aedes aegypti by developing a dose response curve on a lab strain at a standard lab temperature of 25°C by performing a CDC bottle bioassay. The diagnostic dose was found to be 50 μg/mL and the lethal dose, 50% (LD50, the dose required to kill half of the test mosquitoes) was found to be 9 μg/mL. Future testing would need to be completed to compare the deltamethrin dose response curve developed in this study with deltamethrin dose response curves at various different temperatures.
ContributorsEl Sheikha, Mariam D (Co-author) / El Sheikha, Mariam (Co-author) / Paaijmans, Krijn (Thesis director) / Huijben, Silvie (Committee member) / Kalmouni, Joshua (Committee member) / Harrington Bioengineering Program (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
Carbon allotropes are the basis for many exciting advancements in technology. While sp² and sp³ hybridizations are well understood, the sp¹ hybridized carbon has been elusive. However, with recent advances made using a pulsed laser ablation in liquid technique, sp¹ hybridized carbon allotropes have been created. The fabricated carbon chain is composed of sp¹ and sp³ hybridized bonds, but it also incorporates nanoparticles such as gold or possibly silver to stabilize the chain. The polyyne generated in this process is called pseudocarbyne due to its striking resemblance to the theoretical carbyne. The formation of these carbon chains is yet to be fully understood, but significant progress has been made in determining the temperature of the plasma in which the pseudocarbyne is formed. When a 532 nm pulsed laser with a pulsed energy of 250 mJ and pulse length of 10ns is used to ablate a gold target, a peak temperature of 13400 K is measured. When measured using Laser-Induced Breakdown spectroscopy (LIBS) the average temperature of the neutral carbon plasma over one second was 4590±172 K. This temperature strongly suggests that the current theoretical model used to describe the temperature at which pseudocarbyne generates is accurate.
ContributorsWala, Ryland Gerald (Co-author) / Wala, Ryland (Co-author) / Sayres, Scott (Thesis director) / Steimle, Timothy (Committee member) / Drucker, Jeffery (Committee member) / Historical, Philosophical & Religious Studies (Contributor) / Dean, W.P. Carey School of Business (Contributor) / Department of Physics (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
Analog to Digital Converters (ADCs) are a critical component in modern circuit applications. ADCs are used in virtually every application in which a digital circuit is interacting with data from the real world, ranging from commercial applications to crucial military and aerospace applications, and are especially important when interacting with sensors that observe environmental factors. Due to the critical nature of these converters, as well as the vast range of environments in which they are used, it is important that they accurately sample data regardless of environmental factors. These environmental factors range from input noise and power supply variations to temperature and radiation, and it is important to know how each may affect the accuracy of the resulting data when designing circuits that depend upon the data from these ADCs. These environmental factors are considered hostile environments, as they each generally have a negative effect on the operation of an ADC. This thesis seeks to investigate the effects of several of these hostile environmental variables on the performance of analog to digital converters. Three different analog to digital converters with similar specifications were selected and analyzed under common hostile environments. Data was collected on multiple copies of an ADC and averaged together to analyze the results using multiple characteristics of converter performance. Performance metrics were obtained across a range of frequencies, input noise, input signal offsets, power supply voltages, and temperatures. The obtained results showed a clear decrease in performance farther from a room temperature environment, but the results for several other environmental variables showed either no significant correlation or resulted in inconclusive data.
ContributorsSwanson, Taylor Catherine (Co-author) / Millman, Hershel (Co-author) / Barnaby, Hugh (Thesis director) / Garrity, Douglas (Committee member) / Electrical Engineering Program (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
This study measure the effect of temperature on a neural network's ability to detect and classify solar panel faults. It's well known that temperature negatively affects the power output of solar panels. This has consequences on their output data and our ability to distinguish between conditions via machine learning.
ContributorsVerch, Skyler (Author) / Spanias, Andreas (Thesis director) / Tepedelenlioğlu, Cihan (Committee member) / Barrett, The Honors College (Contributor) / Electrical Engineering Program (Contributor)
Created2022-12