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- All Subjects: psychology
- All Subjects: Chemistry
- Genre: Doctoral Dissertation
- Creators: Arizona State University
- Resource Type: Text
Description
Bioparticles comprise a diverse amount of materials ubiquitously present in nature. From proteins to aerosolized biological debris, bioparticles have important roles spanning from regulating cellular functions to possibly influencing global climate. Understanding their structures, functions, and properties provides the necessary tools to expand our fundamental knowledge of biological systems and exploit them for useful applications. In order to contribute to this efforts, the work presented in this dissertation focuses on the study of electrokinetic properties of liposomes and novel applications of bioaerosol analysis. Using immobilized lipid vesicles under the influence of modest (less than 100 V/cm) electric fields, a novel strategy for bionanotubule fabrication with superior throughput and simplicity was developed. Fluorescence and bright field microscopy was used to describe the formation of these bilayer-bound cylindrical structures, which have been previously identified in nature (playing crucial roles in intercellular communication) and made synthetically by direct mechanical manipulation of membranes. In the biological context, the results of this work suggest that mechanical electrostatic interaction may play a role in the shape and function of individual biological membranes and networks of membrane-bound structures. A second project involving liposomes focused on membrane potential measurements in vesicles containing trans-membrane pH gradients. These types of gradients consist of differential charge states in the lipid bilayer leaflets, which have been shown to greatly influence the efficacy of drug targeting and the treatment of diseases such as cancer. Here, these systems are qualitatively and quantitatively assessed by using voltage-sensitive membrane dyes and fluorescence spectroscopy. Bioaerosol studies involved exploring the feasibility of a fingerprinting technology based on current understanding of cellular debris in aerosols and arguments regarding sampling, sensitivity, separations and detection schemes of these debris. Aerosolized particles of cellular material and proteins emitted by humans, animals and plants can be considered information-rich packets that carry biochemical information specific to the living organisms present in the collection settings. These materials could potentially be exploited for identification purposes. Preliminary studies evaluated protein concentration trends in both indoor and outdoor locations. Results indicated that concentrations correlate to certain conditions of the collection environment (e.g. extent of human presence), supporting the idea that bioaerosol fingerprinting is possible.
ContributorsCastillo Gutiérrez, Josemar Andreina (Author) / Hayes, Mark A. (Thesis advisor) / Herckes, Pierre (Committee member) / Ghrilanda, Giovanna (Committee member) / Arizona State University (Publisher)
Created2011
Description
Family adaptation to child developmental disability is a dynamic transactional process that has yet to be tested in a longitudinal, rigorous fashion. In addition, although children with developmental delays frequently have behavior problems, not enough research has examined possible underlying mechanisms in the relation between child developmental delay, adaptation and behavior problems. In the current study, factor analysis examined how best to conceptualize the construct of family adaptation to developmental delay. Also, longitudinal growth curve modeling tested models in which child behavior problems mediated the relation between developmental risk and indices of family adaptation. Participants included 130 typically developing children and their families (Mental Development Index [MDI] > 85) and 104 children with developmental delays and their families (MDI < 85). Data were collected yearly between the ages of three and eight as part of a multi-site, longitudinal investigation examining the interrelations among children's developmental status, family processes, and the emergence of child psychopathology. Results of the current study indicated that adaptation is best conceptualized as a multi-index construct. Different aspects of adaptation changed in unique ways over time, with some facets of adaptation remaining stable while others fluctuated. Child internalizing and externalizing behavior problems were found to decrease over time for both children with developmental delays and typically developing children. Child behavior problems were also found to mediate the relation between developmental risk and family adaptation for over half of the mediation pathways. Significant mediation results indicated that children with developmental delays showed higher early levels of behavior problems, which in turn was associated with more maladaptive adaptation. These findings provide further evidence that families of children with developmental delays experience both positive and more challenging changes in their families over time. This study implies important next steps for research and clinical practice in the area of developmental disability.
ContributorsPedersen y Arbona, Anita (Author) / Crnic, Keith A (Thesis advisor) / Sandler, Irwin (Committee member) / Lemery, Kathryn (Committee member) / Enders, Craig (Committee member) / Arizona State University (Publisher)
Created2011
Description
An emerging body of literature suggests that humans likely have multiple threat avoidance systems that enable us to detect and avoid threats in our environment, such as disease threats and physical safety threats. These systems are presumed to be domain-specific, each handling one class of potential threats, and previous research generally supports this assumption. Previous research has not, however, directly tested the domain-specificity of disease avoidance and self-protection by showing that activating one threat management system does not lead to responses consistent only with a different threat management system. Here, the domain- specificity of the disease avoidance and self-protection systems is directly tested using the lexical decision task, a measure of stereotype accessibility, and the implicit association test. Results, although inconclusive, more strongly support a series of domain-specific threat management systems than a single, domain- general system
ContributorsAnderson, Uriah Steven (Author) / Kenrick, Douglas T. (Thesis advisor) / Shiota, Michelle N. (Committee member) / Neuberg, Steven L. (Committee member) / Becker, David V (Committee member) / Arizona State University (Publisher)
Created2011
Description
Applications of non-traditional stable isotope variations are moving beyond geosciences to biomedicine, made possible by advances in multiple collector inductively coupled plasma mass spectrometry (MC-ICP-MS) technology. Mass-dependent isotope variation can provide information about the sources of elements and the chemical reactions that they undergo. Iron and calcium isotope systematics in biomedicine are relatively unexplored but have great potential scientific interest due to their essential nature in metabolism. Iron, a crucial element in biology, fractionates during biochemically relevant reactions. To test the extent of this fractionation in an important reaction process, equilibrium iron isotope fractionation during organic ligand exchange was determined. The results show that iron fractionates during organic ligand exchange, and that isotope enrichment increases as a function of the difference in binding constants between ligands. Additionally, to create a mass balance model for iron in a whole organism, iron isotope compositions in a whole mouse and in individual mouse organs were measured. The results indicate that fractionation occurs during transfer between individual organs, and that the whole organism was isotopically light compared with food. These two experiments advance our ability to interpret stable iron isotopes in biomedicine. Previous research demonstrated that calcium isotope variations in urine can be used as an indicator of changes in net bone mineral balance. In order to measure calcium isotopes by MC-ICP-MS, a chemical purification method was developed to quantitatively separate calcium from other elements in a biological matrix. Subsequently, this method was used to evaluate if calcium isotopes respond when organisms are subjected to conditions known to induce bone loss: 1) Rhesus monkeys were given an estrogen-suppressing drug; 2) Human patients underwent extended bed rest. In both studies, there were rapid, detectable changes in calcium isotope compositions from baseline - verifying that calcium isotopes can be used to rapidly detect changes in bone mineral balance. By characterizing iron isotope fractionation in biologically relevant processes and by demonstrating that calcium isotopes vary rapidly in response to bone loss, this thesis represents an important step in utilizing these isotope systems as a diagnostic and mechanistic tool to study the metabolism of these elements in vivo.
ContributorsMorgan, Jennifer Lynn Louden (Author) / Anbar, Ariel D. (Thesis advisor) / Wasylenki, Laura E. (Committee member) / Jones, Anne K. (Committee member) / Shock, Everett (Committee member) / Arizona State University (Publisher)
Created2011
Description
When people pick up the phone to call a telephone quitline, they are taking an important step towards changing their smoking behavior. The current study investigated the role of a critical cognition in the cessation process--self-efficacy. Self-efficacy is thought to be influential in behavior change processes including those involved in the challenging process of stopping tobacco use. By applying basic principles of self-efficacy theory to smokers utilizing a telephone quitline, this study advanced our understanding of the nature of self-efficacy in a "real-world" cessation setting. Participants received between one and four intervention calls aimed at supporting them through their quit attempt. Concurrent with the initiation of this study, three items (confidence, stress, and urges) were added to the standard telephone protocol and assessed at each call. Two principal sets of hypotheses were tested using a combination of ANCOVAs and multiple regression analyses. The first set of hypotheses explored how self-efficacy and changes in self-efficacy within individuals were associated with cessation outcomes. Most research has found a positive linear relation between self-efficacy and quit outcomes, but this study tested the possibility that excessively high self-efficacy may actually reflect an overconfidence bias, and in some cases be negatively related to cessation outcomes. The second set of hypotheses addressed several smoking-related factors expected to affect self-efficacy. As predicted, higher baseline self-efficacy and increases in self-efficacy were associated with higher rates of quitting. However, contrary to predictions, there was no evidence that overconfidence led to diminished cessation success. Finally, as predicted, shorter duration of quit attempts, shorter time to relapse, and stronger urges all were associated with lower self-efficacy. In conclusion, understanding how self-efficacy and changes in self-efficacy affect and are affected by cessation outcomes is useful for informing both future research and current quitline intervention procedures.
ContributorsGoesling, Jenna (Author) / Barrera, Manuel (Thesis advisor) / Shiota, Lani (Committee member) / Enders, Craig (Committee member) / Presson, Clark (Committee member) / Arizona State University (Publisher)
Created2011
Description
Intuitive decision making refers to decision making based on situational pattern recognition, which happens without deliberation. It is a fast and effortless process that occurs without complete awareness. Moreover, it is believed that implicit learning is one means by which a foundation for intuitive decision making is developed. Accordingly, the present study investigated several factors that affect implicit learning and the development of intuitive decision making in a simulated real-world environment: (1) simple versus complex situational patterns; (2) the diversity of the patterns to which an individual is exposed; (3) the underlying mechanisms. The results showed that simple patterns led to higher levels of implicit learning and intuitive decision-making accuracy than complex patterns; increased diversity enhanced implicit learning and intuitive decision-making accuracy; and an embodied mechanism, labeling, contributes to the development of intuitive decision making in a simulated real-world environment. The results suggest that simulated real-world environments can provide the basis for training intuitive decision making, that diversity is influential in the process of training intuitive decision making, and that labeling contributes to the development of intuitive decision making. These results are interpreted in the context of applied situations such as military applications involving remotely piloted aircraft.
ContributorsCovas-Smith, Christine Marie (Author) / Cooke, Nancy J. (Thesis advisor) / Patterson, Robert (Committee member) / Glenberg, Arthur (Committee member) / Homa, Donald (Committee member) / Arizona State University (Publisher)
Created2011
Description
The electrode-electrolyte interface in electrochemical environments involves the understanding of complex processes relevant for all electrochemical applications. Some of these processes include electronic structure, charge storage, charge transfer, solvent dynamics and structure and surface adsorption. In order to engineer electrochemical systems, no matter the function, requires fundamental intuition of all the processes at the interface. The following work presents different systems in which the electrode-electrolyte interface is highly important. The first is a charge storage electrode utilizing percolation theory to develop an electrode architecture producing high capacities. This is followed by Zn deposition in an ionic liquid in which the deposition morphology is highly dependant on the charge transfer and surface adsorption at the interface. Electrode Architecture: A three-dimensional manganese oxide supercapacitor electrode architecture is synthesized by leveraging percolation theory to develop a hierarchically designed tri-continuous percolated network. The three percolated phases include a faradaically-active material, electrically conductive material and pore-former templated void space. The micropores create pathways for ionic conductivity, while the nanoscale electrically conducting phase provides both bulk conductivity and local electron transfer with the electrochemically active phase. Zn Electrodeposition: Zn redox in air and water stable N-ethyl-N-methylmorpholinium bis(trifluoromethanesulfonyl)imide, [C2nmm][NTf2] is presented. Under various conditions, characterization of overpotential, kinetics and diffusion of Zn species and morphological evolution as a function of overpotential and Zn concentration are analyzed. The surface stress evolution during Zn deposition is examined where grain size and texturing play significant rolls in compressive stress generation. Morphological repeatability in the ILs led to a novel study of purity in ionic liquids where it is found that surface adsorption of residual amine and chloride from the organic synthesis affect growth characteristics. The drivers of this work are to understand the processes occurring at the electrode-electrolyte interface and with that knowledge, engineer systems yielding optimal performance. With this in mind, the design of a bulk supercapacitor electrode architecture with excellent composite specific capacitances, as well as develop conditions producing ideal Zn deposition morphologies was completed.
ContributorsEngstrom, Erika (Author) / Friesen, Cody (Thesis advisor) / Buttry, Daniel (Committee member) / Sieradzki, Karl (Committee member) / Arizona State University (Publisher)
Created2011
Description
In the present research, two interventions were developed to increase sun protection in young women. The purpose of the study was to compare the effects of intervention content eliciting strong emotional responses to visual images depicting photoaging and skin cancer, specifically fear and disgust, coupled with a message of self-efficacy and benefits of sun protection (the F intervention) with an intervention that did not contain an emotional arousal component (the E intervention). Further, these two intervention conditions were compared to a control condition that contained an emotional arousal component that elicited emotion unrelated to the threat of skin cancer or photoaging (the C control condition). A longitudinal study design was employed, to examine the effects of condition immediately following the intervention, and to examine sun protection behavior 2 weeks after the intervention. A total of 352 undergraduate women at Arizona State University were randomly assigned to one of the three conditions (F n = 148, E n = 73, C n = 131). Several psychosocial constructs, including benefits of sun protection, susceptibility to and severity of photoaging and sun exposure, self-efficacy beliefs of making sun protection a daily habit, and barriers to sun protection were measured before and immediately following the intervention. Sun protection behavior was measured two weeks later. Those in the full intervention reported higher self-efficacy and severity of photoaging at immediate posttest than those in the efficacy only and control conditions. The fit of several path models was tested to explore underlying mechanisms by which the intervention affected sun protection behavior. Experienced emotion, specifically fear and disgust, predicted susceptibility and severity, which in turn predicted anticipated regret of failing to use sun protection. The relationship between this overall threat component (experienced emotion, susceptibility, severity, and anticipated regret) and intentions to engage in sun protection behavior was mediated by benefits. The present research provided evidence of the effectiveness of threat specific emotional arousal coupled with a self-efficacy and benefits message in interventions to increase sun protection. Further, this research provided additional support for the inclusion of both experienced and anticipated emotion in models of health behavior.
ContributorsMoser, Stephanie E (Author) / Aiken, Leona S. (Thesis advisor) / Shiota, Michelle N. (Committee member) / Kwan, Sau (Committee member) / Castro, Felipe (Committee member) / Arizona State University (Publisher)
Created2011
Description
Externalizing behaviors are pervasive, widespread, and disruptive across a multitude of settings and developmental contexts. While the conventional diathesis-stress model typically measures the disordered end of the spectrum, studies that span the range of behavior, from externalizing to competence behaviors, are necessary to see the full picture. To that end, this study examined the additive and nonadditive relations of a dimension of parenting (ranging from warm to rejecting), and variants in dopamine, vasopressin, and neuropeptide-y receptor genes on externalizing/competence in a large sample of predominantly Caucasian twin children in toddlerhood, middle childhood, and early adolescence. Variants within each gene were hypothesized to increase biological susceptibility to both negative and positive environments. Consistent with prediction, warmth related to lower externalizing/higher competence at all ages. Earlier levels of externalizing/competence washed out the effect of parental warmth on future externalizing/competence with the exception of father warmth in toddlerhood marginally predicting change in externalizing/competence from toddlerhood to middle childhood. Warmth was a significant moderator of the heritability of behavior in middle childhood and early adolescence such that behavior was less heritable (mother report) and more heritable (father report) in low warmth environments. Interactions with warmth and the dopamine and vasopressin genes in middle childhood and early adolescence emphasize the moderational role gene variants play in relations between the rearing environment and child behavior. For dopamine, the long variant related to increased sensitivity to parent warmth such that the children displayed more externalizing behaviors when exposed to rejection but they also displayed more competence behaviors when exposed to high warmth. Vasopressin moderation was only present under conditions of parental warmth, not rejection. Interactions with neuropeptide-y and warmth were not significant. The picture that emerges is one of gene-environment interplay, wherein the influence of both parenting and child genotype each depend on the level of the other. As genetic research moves forward, gene variants previously implicated as conferring risk for disorder should be reexamined in conjunction with salient aspects of the environment on the full range of the behavioral outcome of interest.
ContributorsO'Brien, T. Caitlin (Author) / Lemery-Chalfant, Kathryn (Thesis advisor) / Eisenberg, Nancy (Committee member) / Enders, Craig (Committee member) / Nagoshi, Craig (Committee member) / Arizona State University (Publisher)
Created2011
Description
A new challenge on the horizon is to utilize the large amounts of protein found in the atmosphere to identify different organisms from which the protein originated. Included here is work investigating the presence of identifiable patterns of different proteins collected from the air and biological samples for the purposes of remote identification. Protein patterns were generated using high performance liquid chromatography (HPLC). Patterns created could identify high-traffic and low-traffic indoor spaces. Samples were collected from the air using air pumps to draw air through a filter paper trapping particulates, including large amounts of shed protein matter. In complimentary research aerosolized biological samples were collected from various ecosystems throughout Ecuador to explore the relationship between environmental setting and aerosolized protein concentrations. In order to further enhance protein separation and produce more detailed patterns for the identification of individual organisms of interest; a novel separation device was constructed and characterized. The separation device incorporates a longitudinal gradient as well as insulating dielectrophoretic features within a single channel. This design allows for the production of stronger local field gradients along a global gradient allowing particles to enter, initially transported through the channel by electrophoresis and electroosmosis, and to be isolated according to their characteristic physical properties, including charge, polarizability, deformability, surface charge mobility, dielectric features, and local capacitance. Thus, different types of particles are simultaneously separated at different points along the channel distance given small variations of properties. The device has shown the ability to separate analytes over a large dynamic range of size, from 20 nm to 1 μm, roughly the size of proteins to the size of cells. In the study of different sized sulfate capped polystyrene particles were shown to be selectively captured as well as concentrating particles from 103 to 106 times. Qualitative capture and manipulation of β-amyloid fibrils were also shown. The results demonstrate the selective focusing ability of the technique; and it may form the foundation for a versatile tool for separating complex mixtures. Combined this work shows promise for future identification of individual organisms from aerosolized protein as well as for applications in biomedical research.
ContributorsStaton, Sarah J. R (Author) / Hayes, Mark A. (Committee member) / Anbar, Ariel D (Committee member) / Shock, Everett (Committee member) / Williams, Peter (Committee member) / Arizona State University (Publisher)
Created2011