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Does school participatory budgeting (SPB) increase students’ political efficacy? SPB, which is implemented in thousands of schools around the world, is a democratic process of deliberation and decision-making in which students determine how to spend a portion of the school’s budget. We examined the impact of SPB on political efficacy in one middle school in Arizona. Our participants’ (n = 28) responses on survey items designed to measure self-perceived growth in political efficacy indicated a large effect size (Cohen’s d = 1.46), suggesting that SPB is an effective approach to civic pedagogy, with promising prospects for developing students’ political efficacy.
ContributorsGibbs, Norman P. (Author) / Bartlett, Tara Lynn (Author) / Schugurensky, Daniel, 1958- (Author)
Created2021-05-01
Description
Purpose: To examine: (1) whether Non-Hispanic Blacks (NHB) and Non-Hispanic Whites (NHW) with diagnosed arthritis differed in self-reported physical activity (PA) levels, (2) if NHB and NHW with arthritis differed on potential correlates of PA based on the Social Ecological Model (Mcleroy et al., 1988), and (3) if PA participation varied by race/ethnicity after controlling for age, gender, education, and BMI. Methods: This study was a secondary data analysis of data collected from 2006-2008 in Chicago, IL as part of the Midwest Roybal Center for Health Promotion. Bivariate analyses were used to assess potential differences between race in meeting either ACR or ACSM PA guidelines. Comparisons by race between potential socio-demographic correlates and meeting physical activity guidelines were assessed using Chi-squares. Potential differences by race in psychosocial, arthritis, and health-related and environmental correlates were assessed using T-tests. Finally, logistic regression analyses were used to examine if race was still associated with PA after controlling for socio-demographic characteristics. Results: A greater proportion of NHW (68.1% and 35.3%) than NHB (46.5% and 20.9%) met both the arthritis-specific and the American College of Sports Medicine (ACSM) recommendations for physical activity, respectively. NHB had significantly lower self-efficacy for exercise and reported greater impairments in physical function compared to NHW. Likewise, NHB reported more crime and less aesthetics within their neighborhood. NHW were 2.56 times more likely to meet arthritis-specific PA guidelines than NHB after controlling for age, gender, education, marital status, and BMI. In contrast, after controlling for sociodemographic characteristics, age and gender were the only significant predictors of meeting ACSM PA guidelines. Discussion: There were significant differences between NHB and NHW individuals with arthritis in meeting PA guidelines. After controlling for age, gender, education, and BMI non-Hispanic White individuals were still significantly more likely to meet PA guidelines. Interventions aimed at promoting higher levels of physical activity among individuals with arthritis need to consider neighborhood aesthetics and crime when designing programs. More arthritis-specific programs are needed in close proximity to neighborhoods in an effort to promote physical activity.
ContributorsChuran, Christopher (Author) / Der Ananian, Cheryl (Thesis advisor) / Adams, Marc (Committee member) / Campbell, Kathryn (Committee member) / Arizona State University (Publisher)
Created2013
Description
The study of bacterial resistance to antimicrobial peptides (AMPs) is a significant area of interest as these peptides have the potential to be developed into alternative drug therapies to combat microbial pathogens. AMPs represent a class of host-mediated factors that function to prevent microbial infection of their host and serve as a first line of defense. To date, over 1,000 AMPs of various natures have been predicted or experimentally characterized. Their potent bactericidal activities and broad-based target repertoire make them a promising next-generation pharmaceutical therapy to combat bacterial pathogens. It is important to understand the molecular mechanisms, both genetic and physiological, that bacteria employ to circumvent the bactericidal activities of AMPs. These understandings will allow researchers to overcome challenges posed with the development of new drug therapies; as well as identify, at a fundamental level, how bacteria are able to adapt and survive within varied host environments. Here, results are presented from the first reported large scale, systematic screen in which the Keio collection of ~4,000 Escherichia coli deletion mutants were challenged against physiologically significant AMPs to identify genes required for resistance. Less than 3% of the total number of genes on the E. coli chromosome was determined to contribute to bacterial resistance to at least one AMP analyzed in the screen. Further, the screen implicated a single cellular component (enterobacterial common antigen, ECA) and a single transporter system (twin-arginine transporter, Tat) as being required for resistance to each AMP class. Using antimicrobial resistance as a tool to identify novel genetic mechanisms, subsequent analyses were able to identify a two-component system, CpxR/CpxA, as a global regulator in bacterial resistance to AMPs. Multiple previously characterized CpxR/A members, as well as members found in this study, were identified in the screen. Notably, CpxR/A was found to transcriptionally regulate the gene cluster responsible for the biosynthesis of the ECA. Thus, a novel genetic mechanism was uncovered that directly correlates with a physiologically significant cellular component that appears to globally contribute to bacterial resistance to AMPs.
ContributorsWeatherspoon-Griffin, Natasha (Author) / Shi, Yixin (Thesis advisor) / Clark-Curtiss, Josephine (Committee member) / Misra, Rajeev (Committee member) / Nickerson, Cheryl (Committee member) / Stout, Valerie (Committee member) / Arizona State University (Publisher)
Created2013
Description
V(D)J recombination is responsible for generating an enormous repertoire of immunoglobulins and T cell receptors, therefore it is a centerpiece to the formation of the adaptive immune system. The V(D)J recombination process proceeds through two steps, site-specific cleavage at RSS (Recombination Signal Sequence) site mediated by the RAG recombinase (RAG1/2) and the subsequent imprecise resolution of the DNA ends, which is carried out by the ubiquitous non-homologous end joining pathway (NHEJ). The V(D)J recombination reaction is obliged to be tightly controlled under all circumstances, as it involves generations of DNA double strand breaks, which are considered the most dangerous lesion to a cell. Multifaceted regulatory mechanisms have been evolved to create great diversity of the antigen receptor repertoire while ensuring genome stability. The RAG-mediated cleavage reaction is stringently regulated at both the pre-cleavage stage and the post-cleavage stage. Specifically, RAG1/2 first forms a pre-cleavage complex assembled at the boarder of RSS and coding flank, which ensures the appropriate DNA targeting. Subsequently, this complex initiates site-specific cleavage, generating two types of double stranded DNA breaks, hairpin-ended coding ends (HP-CEs) and blunt signal ends (SEs). After the cleavage, RAG1/2 proteins bind and retain the recombination ends to form post-cleavage complexes (PCC), which collaborates with the NHEJ machinery for appropriate transfer of recombination ends to NHEJ for proper end resolution. However, little is known about the molecular basis of this collaboration, partly attributed to the lack of sensitive assays to reveal the interaction of PCC with HP-CEs. Here, for the first time, by using two complementary fluorescence-based techniques, fluorescence anisotropy and fluorescence resonance energy transfer (FRET), I managed to monitor the RAG1/2-catalyzed cleavage reaction in real time, from the pre-cleavage to the post-cleavage stages. By examining the dynamic fluorescence changes during the RAG-mediated cleavage reactions, and by manipulating the reaction conditions, I was able to characterize some fundamental properties of RAG-DNA interactions before and after cleavage. Firstly, Mg2+, known as a physiological cofactor at the excision step, also promotes the HP-CEs retention in the RAG complex after cleavage. Secondly, the structure of pre-cleavage complex may affect the subsequent collaborations with NHEJ for end resolution. Thirdly, the non-core region of RAG2 may have differential influences on the PCC retention of HP-CEs and SEs. Furthermore, I also provide the first evidence of RAG1-mediated regulation of RAG2. Our study provides important insights into the multilayered regulatory mechanisms, in modulating recombination events in developing lymphocytes and paves the way for possible development of detection and diagnotic markers for defective recombination events that are often associated immunodeficiency and/or lymphoid malignancy.
ContributorsWang, Guannan (Author) / Chang, Yung (Thesis advisor) / Levitus, Marcia (Committee member) / Misra, Rajeev (Committee member) / Anderson, Karen (Committee member) / Arizona State University (Publisher)
Created2012
Description
Intrinsic antibiotic resistance is of growing concern in modern medical treatment. The primary action of multidrug resistant strains is through over-expression of active transporters which recognize a broad range of antibiotics. In Escherichia coli, the TolC-AcrAB complex has become a model system to understand antibiotic efflux. While the structures of these three proteins (and many of their homologs) are known, the exact mechanisms of interaction are still poorly understood. By mutational analysis of the TolC turn 1 residues, a drug hypersensitive mutant has been identified which is defective in functional interactions with AcrA and AcrB. Antibiotic resistant revertants carry alterations in both TolC and AcrA act by stabilizing functional complex assembly and opening of the TolC aperture, as monitored by stability of a labile TolC mutant and sensitivity to vancomycin, respectively. Alterations in the AcrB periplasmic hairpin loops lead to a similar antibiotic hypersensitivity phenotype and destabilized complex assembly. Likewise, alterations in TolC which constitutively open the aperture suppress this antibiotic sensitivity. Suppressor alterations in AcrA and AcrB partially restore antibiotic resistance by mediating stability of the complex. The AcrA suppressor alterations isolated in these studies map to the three crystallized domains and it is concluded they alter the AcrA conformation such that it is permanently fixed in an active state, which wild type only transiently goes through when activated by AcrB. Through this genetic evidence, a direct interaction between TolC and AcrB which is stabilized by AcrA has been proposed. In addition to stabilizing the interactions between TolC and AcrB, AcrA is also responsible for triggering opening of the TolC aperture by mediating energy flow from AcrB to TolC. By permanently altering the conformation of AcrA, suppressor mutants allow defective TolC or AcrB mutants to regain functional interactions lost by the initial mutations. The data provide the genetic proof for direct interaction between AcrB and that AcrA mediated opening of TolC requires AcrB as a scaffold.
ContributorsWeeks, Jon William (Author) / Misra, Rajeev (Thesis advisor) / Stout, Valerie (Committee member) / Shi, Yixin (Committee member) / Clark-Curtiss, Josephine (Committee member) / Arizona State University (Publisher)
Created2012
Description
With an excessive amount of resources in the United States healthcare system being spent on the treatment of diseases that are largely preventable through lifestyle change, the need for successful physical activity interventions is apparent. Unfortunately an individual's physical activity and health goals are often not supported by the social context of their daily lives. This single-case design study, Walking Intervention through Text messaging for CoHabiting individuals (WalkIT CoHab), looks at the efficacy of a text based adaptive physical activity intervention to promote walking over a three month period and the effects of social support in intervention performance in three pairs of cohabiting pairs of individuals (n=6). Mean step increase from baseline to intervention ranged from 1300 to 3000 steps per day for all individuals, an average 45.87% increase in physical activity. Goal attainment during the intervention ranged from 43.96% to 71.43%, meaning all participants exceeded the 40% success rate predicted by 60th percentile goals. Social support scores for study partners, unlike social support scores for family and friends, were often in the high social support range and had a moderate increase from pre to post visits for most participants. Although there was variation amongst participants, there was a high correlation in physical activity trends and successful goal attainment in each pair of participants. Less ambitious percentile goals and more personalized motivational text messages might be beneficial to some participants. An extended intervention, something the majority of participants expressed interest in, would further support the efficacy of this behavioral intervention and allow for possible long term benefits of social support in the intervention to be investigated.
ContributorsFernandez, Jacqueline Alyssa (Author) / Adams, Marc (Thesis director) / Angadi, Siddhartha (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor)
Created2015-05
Description
An increasingly sedentary population in the United States, specifically with adolescents, is putting youth at risk of future health related trauma and disease. This single-case design study, Walking Intervention Through Text Messaging for Adolescents (WalkIT-A), was used to intervene with a 12-year old, physically inactive male, in an attempt to test the efficacy of a 12-week physical activity program that may help reduce health risks by increasing number of steps walked per day. The components of the intervention consisted of a FitBit Zip pedometer, physical activity education, text messages, monetary incentives, and goal setting that adapted personally to the participant. Mean step count increased by 30% from baseline (mean = 3603 [sd = 1983]) to intervention (mean = 4693 [sd = 2112]); then increased slightly by 6.7% from intervention to withdrawal (mean = 5009 [sd = 2152]). Mean "very active minutes" increased by 45% from baseline (mean = 8.8 [sd = 8.9]) to intervention (mean = 12.8 [sd = 9.6]); then increased by 61.7% from intervention to withdrawal (mean = 20.7 [sd = 8.4]). Weight, BMI, and blood pressure all increased modestly from pre to post. Cardiovascular fitness (estimated VO2 max) improved by 12.5% from pre (25.5ml*kg-1*min-1) to post (28.7ml*kg-1*min-1). The intervention appeared to have a delayed and residual effect on the participant's daily steps and very active minutes. Although the idealistic ABA pattern did not occur, and the participant did not meet the target of 11,500 daily steps, a positive trend toward that target behavior in the latter 1/3rd of the intervention was observed. Results suggest the need for an extended intervention over a longer period of time and customized even further to the participant.
ContributorsLamb, Nicholas Reid (Author) / Adams, Marc (Thesis director) / Ainsworth, Barbara (Committee member) / Barrett, The Honors College (Contributor) / School of Nutrition and Health Promotion (Contributor)
Created2014-12
Description
Dengue virus infects millions of people every year. Yet there is still no vaccine available to prevent it. Here we use a neutralizing epitope determinant on the dengue envelope (E) protein as an immunogen to be vectored by a measles virus (MV) vaccine. However the domain III (DIII) of the dengue 2 E protein is too small to be immunogenic by itself. In order for it to be displayed on a larger particle, it was inserted into the amino terminus of small hepatitis B surface antigen (HBsAg, S) coding sequence. To generate the recombinant MV vector and verify the efficiency of this concept, a reverse genetics system was used where the MV vectors express one or two additional transcription units to direct the assembly of hybrid HBsAg particles. Two types of recombinant measles virus were produced: pB(+)MVvac2(DIII-S,S)P and pB(+)MVvac2(DIII-S)N. Virus recovered from pB(+)MVvac2(DIII-S,S)P was viable. An ELISA assay was performed to demonstrate the expression and secretion of HBsAg. Supernatant from MVvac2(DIII-S,S)P infected cells confirmed that hybrid HBsAg-domain III particles with a density similar to traditional HBsAg particles were released. Characteristics of the subviral particle have been analyzed for the successful incorporation of domain III. The replication fitness of the recombinant MV was evaluated using multi-step growth kinetics and showed reduced replication fitness when compared to the parental strain MVvac2. This demonstrates that viral replication is hindered by the addition of the two inserts into MV genome. Further analysis of MVvac2(DIII-S)N is needed to justify immune response studies in a small animal model using both of the generated recombinant vectors.
ContributorsHarahap, Indira Saridewi (Author) / Reyes del Valle, Jorge (Thesis director) / Hogue, Brenda (Committee member) / Misra, Rajeev (Committee member) / Barrett, The Honors College (Contributor) / T. Denny Sanford School of Social and Family Dynamics (Contributor) / School of Human Evolution and Social Change (Contributor) / School of Life Sciences (Contributor)
Created2014-05
Description
The WalkIT Study is a mobile health study examining the efficacy of a four month text message-based intervention for increasing physical activity among 96 overweight adults. The purpose of this thesis is to examine the potency of the different types of motivational prompt-to-action text messages used in the WalkIT Study for increasing steps per day by examining the individual messages, creating qualitative themes and comparing themed groups, and evaluating the interaction between demographic subgroups and themed groups. A total of nine themes was created. The results found that Message 13, “It doesn't matter how old you are – it's never too early or too late to become physically active so start today; only then will you start to see results!”, had the highest median step count (7129 steps) and Message 71, “It's ok if you can't reach your goal today. Just push yourself more tomorrow.”, had the lowest median step count (5054 steps). For themes, the highest median step count (6640 steps) was found in Theme 6, Challenges, and the lowest median step count (5450 steps) was found in Theme 9, Unconditional Feedback. Theme 6 (Challenges) had the highest median step count for females, Theme 7 (Everyday Tips) had the highest median step count for males, Theme 4 (Nutrition) had the highest median step count for the 18-42 group, Theme 6 (Challenges) had the highest median step count for the 43-61 group, and Theme 9 (Unconditional Feedback) had the lowest median step count for both genders and both age groups. The results suggest the usefulness of analyzing the effectiveness of individual motivational text messages, themes, and the interaction between demographic groups and themes in physical activity interventions.
ContributorsBhuiyan, Nishat Anjum (Author) / Adams, Marc (Thesis director) / Ainsworth, Barbara (Committee member) / Barrett, The Honors College (Contributor) / School of Nutrition and Health Promotion (Contributor)
Created2015-05
Description
Protein folding is essential in all cells, and misfolded proteins cause many diseases. In the Gram-negative bacterium Escherichia coli, protein folding must be carefully controlled during envelope biogenesis to maintain an effective permeability barrier between the cell and its environment. This study explores the relationship between envelope biogenesis and cell stress, and the return to homeostasis during envelope stress. A major player in envelope biogenesis and stress response is the periplasmic protease DegP. Work presented here explores the growth phenotypes of cells lacking degP, including temperature sensitivity and lowered cell viability. Intriguingly, these cells also accumulate novel cytosolic proteins in their envelope not present in wild-type. Association of novel proteins was found to be growth time- and temperature-dependent, and was reversible, suggesting a dynamic nature of the envelope stress response. Two-dimensional gel electrophoresis of envelopes followed by mass spectrometry identified numerous cytoplasmic proteins, including the elongation factor/chaperone TufA, illuminating a novel cytoplasmic response to envelope stress. A suppressor of temperature sensitivity was characterized which corrects the defect caused by the lack of degP. Through random Tn10 insertion analysis, aribitrarily-primed polymerase chain reaction and three-factor cross, the suppressor was identified as a novel duplication-truncation of rpoE, here called rpoE'. rpoE' serves to subtly increase RpoE levels in the cell, resulting in a slight elevation of the SigmaE stress response. It does so without significantly affecting steady-state levels of outer membrane proteins, but rather by increasing proteolysis in the envelope independently of DegP. A multicopy suppressor of temperature sensitivity in strains lacking degP and expressing mutant OmpC proteins, yfgC, was characterized. Bioinformatics suggests that YfgC is a metalloprotease, and mutation of conserved domains resulted in mislocalization of the protein. yfgC-null mutants displayed additive antibiotic sensitivity and growth defects when combined with null mutation in another periplasmic chaperone, surA, suggesting that the two act in separate pathways during envelope biogenesis. Overexpression of YfgC6his altered steady-state levels of mutant OmpC in the envelope, showing a direct relationship between it and a major constituent of the envelope. Curiously, purified YfgC6his showed an increased propensity for crosslinking in mutant, but not in a wild-type, OmpC background.
ContributorsLeiser, Owen Paul (Author) / Misra, Rajeev (Thesis advisor) / Jacobs, Bertram (Committee member) / Chang, Yung (Committee member) / Stout, Valerie (Committee member) / Arizona State University (Publisher)
Created2010