Matching Items (12,694)
Filtering by
- Creators: ASU Library. Music Library
Description
Background
The transmission dynamics of Tuberculosis (TB) involve complex epidemiological and socio-economical interactions between individuals living in highly distinct regional conditions. The level of exogenous reinfection and first time infection rates within high-incidence settings may influence the impact of control programs on TB prevalence. The impact that effective population size and the distribution of individuals’ residence times in different patches have on TB transmission and control are studied using selected scenarios where risk is defined by the estimated or perceive first time infection and/or exogenous re-infection rates.
Methods
This study aims at enhancing the understanding of TB dynamics, within simplified, two patch, risk-defined environments, in the presence of short term mobility and variations in reinfection and infection rates via a mathematical model. The modeling framework captures the role of individuals’ ‘daily’ dynamics within and between places of residency, work or business via the average proportion of time spent in residence and as visitors to TB-risk environments (patches). As a result, the effective population size of Patch i (home of i-residents) at time t must account for visitors and residents of Patch i, at time t.
Results
The study identifies critical social behaviors mechanisms that can facilitate or eliminate TB infection in vulnerable populations. The results suggest that short-term mobility between heterogeneous patches contributes to significant overall increases in TB prevalence when risk is considered only in terms of direct new infection transmission, compared to the effect of exogenous reinfection. Although, the role of exogenous reinfection increases the risk that come from large movement of individuals, due to catastrophes or conflict, to TB-free areas.
Conclusions
The study highlights that allowing infected individuals to move from high to low TB prevalence areas (for example via the sharing of treatment and isolation facilities) may lead to a reduction in the total TB prevalence in the overall population. The higher the population size heterogeneity between distinct risk patches, the larger the benefit (low overall prevalence) under the same “traveling” patterns. Policies need to account for population specific factors (such as risks that are inherent with high levels of migration, local and regional mobility patterns, and first time infection rates) in order to be long lasting, effective and results in low number of drug resistant cases.
The transmission dynamics of Tuberculosis (TB) involve complex epidemiological and socio-economical interactions between individuals living in highly distinct regional conditions. The level of exogenous reinfection and first time infection rates within high-incidence settings may influence the impact of control programs on TB prevalence. The impact that effective population size and the distribution of individuals’ residence times in different patches have on TB transmission and control are studied using selected scenarios where risk is defined by the estimated or perceive first time infection and/or exogenous re-infection rates.
Methods
This study aims at enhancing the understanding of TB dynamics, within simplified, two patch, risk-defined environments, in the presence of short term mobility and variations in reinfection and infection rates via a mathematical model. The modeling framework captures the role of individuals’ ‘daily’ dynamics within and between places of residency, work or business via the average proportion of time spent in residence and as visitors to TB-risk environments (patches). As a result, the effective population size of Patch i (home of i-residents) at time t must account for visitors and residents of Patch i, at time t.
Results
The study identifies critical social behaviors mechanisms that can facilitate or eliminate TB infection in vulnerable populations. The results suggest that short-term mobility between heterogeneous patches contributes to significant overall increases in TB prevalence when risk is considered only in terms of direct new infection transmission, compared to the effect of exogenous reinfection. Although, the role of exogenous reinfection increases the risk that come from large movement of individuals, due to catastrophes or conflict, to TB-free areas.
Conclusions
The study highlights that allowing infected individuals to move from high to low TB prevalence areas (for example via the sharing of treatment and isolation facilities) may lead to a reduction in the total TB prevalence in the overall population. The higher the population size heterogeneity between distinct risk patches, the larger the benefit (low overall prevalence) under the same “traveling” patterns. Policies need to account for population specific factors (such as risks that are inherent with high levels of migration, local and regional mobility patterns, and first time infection rates) in order to be long lasting, effective and results in low number of drug resistant cases.
ContributorsMoreno Martinez, Victor (Author) / Espinoza Cortes, Baltazar (Author) / Barley, Kamal (Author) / Paredes Gutierrez, Marlio (Author) / Bichara, Derdei (Author) / Mubayi, Anuj (Author) / Castillo-Chavez, Carlos (Author) / Simon M. Levin Mathematical, Computational and Modeling Sciences Center (Contributor) / College of Liberal Arts and Sciences (Contributor) / School of Human Evolution and Social Change (Contributor)
Created2017-01-11
Description
Visual aides, such as PowerPoint slides, hand-outs, and lecture notes on whiteboards, are often used in classrooms to convey important content to learners, especially in high school and college. When using these visual learning aides, it is important to consider which qualities of these presentations can affect learning— positively or negatively—and how those qualities interact with individual student characteristics. In the present study, we examine the overlap between audio and text and how the effects of overlap potentially interact with reading comprehension abilities. The examination of these potential influences on learning in this study is inspired by Cognitive Load Theory, the Dual-Channel Assumption, and prior research.
ContributorsHarry, Danielle (Author) / McNamara, Danielle (Thesis director) / Presson, Clark (Committee member) / Jackson, Tanner (Committee member) / Roscoe, Rod (Committee member) / Barrett, The Honors College (Contributor) / College of Liberal Arts and Sciences (Contributor)
Created2012-12
Description
Prospective memory is defined as remembering to carry out specified actions in the future. Research has suggested that prospective memory retrieval is reliant on multiple cognitive processes to function, and the ways in which these different processes are used is dependent on a variety of variables relating to the prospective memory task at hand. The current study focuses on the strength of the association between the prospective
memory cue and the prospective memory intention. Based on literature suggesting that aspects of prospective memory are reliant on executive control functioning, the current study examined the possibility that executive control depletion would affect prospective memory ability on subsequent tasks. Results showed that depletion of executive control resources, measured objectively, did not impair prospective memory in either a low or
high cue-association condition. However, participants‟ subjective assessment of their own fatigue correlated significantly with their subsequent prospective memory performance, regardless of association condition. The results of the study indicate that depletion studies that fail to account for both objective and subjective measures suffer from an unclear interpretation of effects, and that recognition of perceived expectancies
of cognitive resource limitation can assist in improving prospective memory ability.
memory cue and the prospective memory intention. Based on literature suggesting that aspects of prospective memory are reliant on executive control functioning, the current study examined the possibility that executive control depletion would affect prospective memory ability on subsequent tasks. Results showed that depletion of executive control resources, measured objectively, did not impair prospective memory in either a low or
high cue-association condition. However, participants‟ subjective assessment of their own fatigue correlated significantly with their subsequent prospective memory performance, regardless of association condition. The results of the study indicate that depletion studies that fail to account for both objective and subjective measures suffer from an unclear interpretation of effects, and that recognition of perceived expectancies
of cognitive resource limitation can assist in improving prospective memory ability.
ContributorsCook, Carson (Author) / Brewer, Gene (Thesis director) / Presson, Clark (Committee member) / Homa, Donald (Committee member) / Barrett, The Honors College (Contributor) / College of Liberal Arts and Sciences (Contributor)
Created2012-12
Description
The effects of meditation on attention control have been widely studied in recent years. However, the methodological flaws of many of these studies raise serious concerns on the validity of meditation training as a cognitive enhancer. This study investigated the near and far transfer effects of mindfulness meditation training on attention control when a stringent experimental design was implemented. Participants in the experimental group practiced meditation for three twenty-minute sessions, and participants in the active control group listened to an audio book about meditation for similar times. No significant effect of meditation on change in performance on cognitive tasks was found. This study suggests that short-term mindfulness meditation training does not result in increased attention control.
ContributorsPatel, Sachi Rajul (Author) / Brewer, Gene (Thesis director) / Presson, Clark (Committee member) / Davis, Mary (Committee member) / Barrett, The Honors College (Contributor) / Department of Chemistry and Biochemistry (Contributor) / Department of Psychology (Contributor) / School of Historical, Philosophical and Religious Studies (Contributor)
Created2013-05
Description
Gift-giving economies are economic models that freely give resources rather than barter for them or purchase them from market. Need-based transfers fit into this economic model by freely giving resources on the basis of need, provided the giver can spare the resources. The Maasai are an East African pastoral tribe that practices need-based transfers through a tradition they call osotua. If they have a partner with an established osotua relationship, then they will give any amount of cattle that partner request, provided they can spare the cattle. Cheating each other is unheard of in this tradition, but for this simulation I am introducing cheating into this economic model through feigning need. If a cheater is not in need, they will act like they are in need. If they are in need, then the cheater will request more cattle than what they need to survive. I am testing two different responses to cheating: walking-away and punishing. In the walk-away condition, the victim ends their osotua partnership and establishes a new one. In the punishment condition, a portion of the cheater's stolen cattle is destroyed.
ContributorsDunkelberger, Sophia (Author) / Aktipis, Athena (Thesis director) / Presson, Clark (Committee member) / Johnson, Kathryn (Committee member) / School of Social and Behavioral Sciences (Contributor) / Department of Psychology (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
In recent years the abuse of synthetic cathinones, "Bath Salts," has increased. The purpose of this study was to analyze two synthetic cathinones, methylone and α-pvp, for hedonic properties or the potential to be abused. This was tested using an intracranial self-stimulation paradigm, a robust measurement for reward. It was found methylone resulted in an abuse potential similar to MDMA, ecstasy, abuse. Moreover, the results for α-pvp showed a high liability for abuse.
ContributorsJohnson, Craig Trevor (Author) / Olive, Foster (Thesis director) / Presson, Clark (Committee member) / Montesano, Mark (Committee member) / Barrett, The Honors College (Contributor) / Mechanical and Aerospace Engineering Program (Contributor) / Department of Psychology (Contributor)
Created2013-12
Description
There is preclinical evidence that the detrimental cognitive effects of hormone loss can be ameliorated by estrogen therapy (Bimonte, Acosta, & Talboom, 2010), however, one of the primary concerns with current hormone therapies is that they are nonselective, leading to increased risk of breast and endometrial cancers as well as heart disease. Thus, in order to achieve a successful and clinically relevant long-term hormone therapy option, it is optimal to find an estrogen therapy regimen that is selective to its target tissue. Recently, phytoestrogens have been found to exert selective, beneficial effects on cognition and brain. For example, genistein and diadzein produce neuroprotective effects in cognitive brain regions (Zhao, Chen, & Diaz Brinton, 2002). The purpose of this study was threefold: 1) to examine the cognitive impact of phytoestrogens in young ovariectomized rats, 2) to replicate the dose effects found in the Luine study (Luine et al., 2006), while controlling for manufacturer differences, and 3) to assess if the rodent diet used in our laboratory has an estrogenic-like cognitive impact.The current findings suggest that, at least for object memory, diets containing varying amounts of phytoestrogens can alter cognition, with diets containing high amounts of phytoestrogens showing potential benefits to this type of memory.
ContributorsWhitton, Elizabeth Nicole (Author) / Bimonte-Nelson, Heather (Thesis director) / Presson, Clark (Committee member) / Baxter, Leslie (Committee member) / Barrett, The Honors College (Contributor) / Department of Psychology (Contributor)
Created2013-05
Description
The purpose of the present study was to evaluate if the size of food items is an important dimension of food incentive in rats. The experiment involved training rats on a T-maze with 1, 45 mg pellet and 7, 5 mg pellets in one alternative and 8, 10 mg pellets in the other alternative. Results from this study indicated that the rats showed preference for the alternative that contained the 1, 45 mg pellet surrounded by 7, 5 mg pellets. Thus, rats preferred the food set that contained the larger sized food unit to an equicaloric food set with only smaller sized food units. In regards to running speed, no significant differences were found for either alternative of food. Results from this study indicated that the apparent size of an item could be a factor in the incentive value of food and perhaps, rats used size as a heuristic, placing a higher incentive value on the food set that contained the larger sized food unit than one containing only smaller sized food units.
ContributorsAnderson, Ashley Linnea (Author) / Phillips, Elizabeth Capaldi (Thesis director) / Presson, Clark (Committee member) / Cohen, Adam (Committee member) / Barrett, The Honors College (Contributor) / Department of Psychology (Contributor)
Created2013-05
Description
Approximately 95% of Americans have at least one sibling (Weaver, Coleman, & Ganong, 2003), making it more likely that children grow up with a sibling than with a father (Lyon, 2009). It is therefore somewhat surprising to learn that sibling relationships have not been a central focus of psychological research, especially considering the fact that parent-child and peer relationships have been studied so extensively. There is no doubt that parents and peers have profound effects on children's emotional, psychological and social wellbeing, but siblings have important effects as well. By middle childhood, children spend more time with their siblings than they do with their parents (Pike, Coldwell, & Dunn, 2005). The sibling relationship is one of the longest and most lasting relationships that we as humans have. Approximately 78% of Americans over the age of sixty still have contact with at least one sibling (Cicirelli, 1995). Unlike parents, siblings are often in our lives until the end of our lifespan and, unlike friends, we do not choose them. They act as teachers, friends, and critics, just to name a few, and they are often a sounding board off of which we can test our ideas and behaviors. The focus of the current study is on the twin sibling relationship quality in middle childhood and in adolescence and its implications for individual adjustment, specifically in the realm of prosocial and aggressive behaviors. I evaluated twin sibling cooperation and conflict at both age 7-8 years and age 12-14 years and then examined prosocial and aggressive tendencies concurrently and longitudinally to study the strength of the association between the two. This study also aimed to better understand the extent to which prosocial behavior and aggression are influenced by genetic and environmental factors.
ContributorsDitto, Kayla Rhiannon Loretta Cam (Author) / Lemery-Chalfant, Kathryn (Thesis director) / Presson, Clark (Committee member) / Valiente, Carlos (Committee member) / Barrett, The Honors College (Contributor) / Department of Psychology (Contributor)
Created2013-05
Description
I propose that norms regulate behaviors that negatively impact an individual's survival and reproduction. But because monitoring and enforcing of norms can be costly, individuals should be selective about which norms they police and under what circumstances they should do so. Two studies tested this idea by experimentally activating fitness-relevant motives and having participants answer questions about the policing of norms. The first study examined a norm prescribing respect for status and another proscribing sexual coercion. Results from Study 1 failed to support the hypotheses; activating a status-seeking motive did not have the predicted effects on policing of the respect-status norm nor did activating a mating motive have the predicted effects on policing of the respect-status norm or anti-coercion norm. Study 2 examined two new norms, one prescribing that people stay home when sick and the other proscribing people from having sex with another person's partners. Study 2 also manipulated whether self or others were the target of the policing. Study 2 failed to provide support; a disease avoidance motive failed to have effects on policing of the stay home when sick norm. Individuals in a relationship under a mating motive wanted less policing of others for violation of the mate poaching norm than those in a baseline condition, opposite of the predicted effects.
ContributorsSmith, M. Kristopher (Author) / Neuberg, L. Steven (Thesis director) / Presson, Clark (Committee member) / Hruschka, J. Daniel (Committee member) / Barrett, The Honors College (Contributor) / College of Liberal Arts and Sciences (Contributor)
Created2013-05