283 research outputs found
Integrating text-messaging and web-based interventions to improve physical activity and nutrition among college students
Regular physical activity and the inclusion of fruits and vegetables in dietary intake contribute to a variety of positive health outcomes and improve quality of life. With more than half of college students falling short of government guidelines for exercise and nutrition (ACHA, 2009), effective interventions targeting young adults during this transitional time are critical. Mobile phone use has become increasingly common among college students, providing an opportunity to develop intervention strategies that may be better integrated into their daily lives. Research on intervention components delivered by phone is essential for developing easily utilized, efficacious nutrition and physical activity interventions for students. Study objectives were (1) to examine the utility of a combined web-based and text-messaging intervention for physical activity and nutrition among college students, and (2) to examine the value of text message tailoring to maximize improvement in these outcomes. Students recruited from introductory psychology classes (n=151) completed measures of physical activity and nutrition at baseline and one-month follow-up. Students were randomized into one of four conditions: assessment only, web-based health behaviors feedback only, web-based feedback with standardized daily text-messages, web-based feedback with tailored daily text-messages. Primary hypotheses were that the intervention that combined web-based feedback with tailored daily text-messages would result in increased physical activity, increased fruit and vegetable intake, and greater likelihood of meeting government standards for these behaviors at follow-up compared to the assessment control condition. Regression analyses were performed with planned contrasts between experimental conditions to examine the additive impact of each intervention component on primary outcomes. Secondary analyses were conducted on additional nutrition and physical activity outcomes. Exploratory analyses were conducted to examine whether individual difference variables moderated the influence of the intervention on outcomes. Study hypotheses were not supported. No significant effect was observed for the intervention on physical activity or nutrition outcomes. These findings may suggest the need for more intensive intervention strategies to impact behavior. Future iterations should include two-way text-message communication and feedback to increase depth-of-processing, alternative tailoring approaches based on self-reported goal-systems variables, and further exploration of intervention components that may improve physical activity and nutrition among college students
Self, family and society in Nadine Gordimer's Burger's Daughter, Rachel Zadok's Gem Squash Tokoloshe, and Doris Lessings's The Grass is Singing
This dissertation examines Nadine Gordimerās Burgerās Daughter, Rachel Zadokās Gem Squash Tokoloshe, and Doris Lessingās The Grass is Singing. It focuses on the development of each of the protagonistsā identities in three realms: the individual, the familial and the societal. Additionally, it is concerned with the specific socio-political contexts in which the novels are set. It employs psychoanalytic and historical materialist frameworks in order to engage with the disparate areas of identity with which it is concerned. The introduction establishes the analytical perspective of the dissertation and explores the network of theoretical frames on which the dissertation relies. Additionally, it contextualises each of the novels, within their historical contexts, as well as in relation to the theory. The first chapter examines Nadine Gordimerās Burgerās Daughter. It focuses on the protagonistās assertion of an identity independent of her fatherās role as a political activist, and her eventual acceptance of the universal difficulty in negotiating a life which is both private and political. The second chapter, on Rachel Zadokās Gem Squash Tokoloshe, examines the relationship between the protagonistās traumatic experiences as a child and her inability to assert an identity as an adult. The similarities between the protagonistās attempts to address her traumas and thereby create herself anew and South Africaās employment of the Truth and Reconciliation Commission as a means to acknowledge and engage with its traumatic history is of import. The third chapter which deals with Doris Lessingās The Grass is Singing traces the life of its protagonist, whose identifications remain childish as a result of having witnessed her parentsā difficult relationship. Her understanding of the world is informed by a rigid, binary understanding, which is ultimately disrupted by her relationship with a black employee. She is incapable of readjusting her frame of reference, however, and ultimately goes mad. I conclude that, while my focus has been on personal, familial and social identifications, the standard terms in which identity is examined, namely, race, class, and gender, are present in each of the three tiers of identity with which I have been concerned
Finding human genetic variation in whole genome expression data with applications for āmissingā heritability: The GWCoGAPS algorithm, the PatternMarkers statistic, and the ProjectoR package
Starting from a single fertilized egg, the compendium of human cells is generated via stochastic perturbations of earlier generations. Concurrently, canalization of developmental pathways limits the type and degree of variation to ensure viability; thus, it is unsurprising that deviations early in life have been linked to late manifesting diseases. Human pluripotent stem cells (hPSCs) are a highly robust and uniquely human experimental system in which to model the sources and consequences of this variability. Further, variation in hPSCsā transcriptomes has been directly linked to both genomic background and biases in differentiation efficiency. Taking advantage of this link between genomic background and developmental phenotypes, we developed Genome-Wide CoGAPS Analysis in Parallel Sets (GWCoGAPS), the first robust whole genome Bayesian non-negative matrix factorization (NMF), to find conserved transcriptional signatures representative of the functional effect of human genetic variation. Time course RNA-seq data obtained from three human embryonic stem cells (ESC) and three human induced pluripotent stem cells (IPSC) in three different experimental conditions was analyzed. GWCoGAPS distinguished shared developmental trajectories from unique transcriptional signatures of each of the cell lines. Further analysis of these āidentityā signatures found they were predictive of lineage biases during neuronal differentiation. Additionally, lineage biases were consistent with early differences in morphogenetic phenotypes within monolayer culture, thus, linking transcriptional genomic signatures to stable quantifiable cellular features. To test whether the cell line signatures were genome specific, we next developed the projectoR algorithm to assess a given signatures robustness in independent data sets. By using the identity signatures as inputs to projectoR, we were able to identify samples from the same donor genome in datasets from multiple tissues and across technical platforms, including RNA-seq results from post-mortem brain, micro arrayed embryoid bodies, and publicly available datasets. The identification of signatures that define the functional rather than physical background of an individualās genome has the potential to profoundly influence our view of human variation and disease
A Standardized Protocol for Measuring Bioelectrical Impedance in Green Turtles (Chelonia mydas)
Bioelectrical impedance analysis (BIA) is gaining popularity in wildlife studies as a portable technology for immediate and nondestructive predictions of body composition components, such as fat-free and fat masses. Successful application of BIA for field-based research requires the identification and control of potential sources of error, as well as the creation of and adherence to a standardized protocol for measurement. The aim of our study was to determine sources of error and to provide a standardization protocol to improve measurement precision of BIA on juvenile green turtles (Chelonia mydas; n=35
). We assessed the effects of altered environmental temperature (20Ā°Cā30Ā°C), postprandial state (2ā72 h), and time out of the water (2 h) on five impedance parameters (resistance at infinite frequency [Rinf], resistance at zero frequency [R0], resistance at 50 kHz [R50], phase angle at 50 kHz [PhA50], and intracellular resistance [Ri]) using a bioimpedance spectroscopy device. Technical reproducibility of measurements and interanimal variability were also assessed. We found an inverse exponential relationship between change in environmental temperature and impedance parameters Rinf, R0, and R50. Postprandial state significantly increased Rinf and Ri 72 h after feeding. BIA measurements were reproducible within individual juvenile green turtles at temperatures from 20Ā°C to 30Ā°C. Significant variation in impedance values was found between animals at all temperatures, sampling times, and postprandial states, but the relative differences (%) were small in magnitude. Our study suggests that measurement precision is improved by measuring animals at consistent environmental temperatures close to their preferred thermal range. We propose a standardized protocol of measurement conditions to facilitate laboratory and field use of BIA for body composition assessment studies in turtles
Evaluation of Three Sources of Validity Evidence for a Laparoscopic Duodenal Atresia Repair Simulator
Purpose: Laparoscopic duodenal atresia (DA) repair is a relatively uncommon pediatric operation requiring advanced minimally invasive skills. Currently, there are no commercial simulators available that address surgeons' needs for refining skills associated with this procedure. The purposes of this study were (1) to create an anatomically correct, size-relevant model and (2) to evaluate the content validity of the simulator. Materials and Methods: Radiologic images were used to create an abdominal domain consistent with a full-term infant. Fetal bovine tissue was used to complete the simulator. Following Institutional Review Board exempt determination, 18 participants performed the simulated laparoscopic DA repair. Participants completed a self-report, six-domain, 24-item instrument consisting of 4-point rating scales (from 1=not realistic to 4=highly realistic). Validity evidence relevant to test content and response processes was evaluated using the many-facet Rasch model, and evidence of internal structure (inter-item consistency) was estimated using Cronbach's alpha. Results: The highest observed averages were for ?Value as a training and testing tool? (both observed averages=3.9), whereas the lowest ratings were ?Palpation of liver? (observed average=3.3) and ?Realism of skin? (observed average=3.2). The Global opinion rating was 3.2, indicating the simulator can be considered for use as is, but could be improved slightly. Inter-item consistency was high (Ī±=0.89). Conclusions: We have successfully created a size-appropriate laparoscopic DA simulator. Participants agreed that the simulator was relevant and valuable as a learning/testing tool. Prior to implementing this simulator as a training tool, minor improvements should be made, with subsequent evaluation of additional validation evidence.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/140148/1/lap.2014.0358.pd
Evaluation of Three Sources of Validity Evidence for a Synthetic Thoracoscopic Esophageal Atresia/Tracheoesophageal Fistula Repair Simulator
Purpose: Thoracoscopic esophageal atresia (EA)/tracheoesophageal fistula (TEF) repair is technically challenging. We have previously reported our experiences with a high-fidelity hybrid model for simulation-based educational instruction in thoracoscopic EA/TEF, including the high cost of the tissue for these models. The purposes of this study were (1) to create a low-cost synthetic tissue EA/TEF repair simulation model and (2) to evaluate the content validity of the synthetic tissue simulator. Materials and Methods: Review of the literature and computed tomography images were used to create computer-aided drawings (CAD) for a synthetic, size-appropriate EA/TEF tissue insert. The inverse of the CAD image was then printed in six different sections to create a mold that could be filled with platinum-cured silicone. The silicone EA/TEF insert was then placed in a previously described neonatal thorax and covered with synthetic skin. Following institutional review board?exempt determination, 47 participants performed some or all of a simulated thoracoscopic EA/TEF during two separate international meetings (International Pediatric Endosurgery Group [IPEG] and World Federation of Associations of Pediatric Surgeons [WOFAPS]). Participants were identified as ?experts,? having 6?50 self-reported thoracoscopic EA/TEF repairs, and ?novice,? having 0?5 self-reported thoracoscopic EA/TEF repairs. Participants completed a self-report, six-domain, 24-item instrument consisting of 23 5-point rating scales and one 4-point Global Rating Scale. Validity evidence relevant to test content and response processes was evaluated using the many-facet Rasch model, and evidence of internal structure (interitem consistency) was estimated using Cronbach's alpha. Results: A review of the participants' ratings indicates there were no overall differences across sites (IPEG versus WOFAPS, P=.84) or experience (expert versus novice, P=.17). The highest observed averages were 4.4 (Value of Simulator as a Training Tool), 4.3 (Physical Attributes?chest circumference, chest depth, and intercostal space), and 4.3 (Realism of Experience?fistula location). The lowest observed averages were 3.5 (Ability to Perform?closure of fistula), 3.7 (Ability to Perform?acquisition target trocar sites), 3.8 (Physical Attributes?landmark visualization), 3.8 (Ability to Perform?anastomosis and dissection of upper pouch), and 3.9 (Realism of Materials?skin). The Global Rating Scale was 2.9, coinciding with a response of ?this simulator can be considered for use in neonatal TEF repair training, but could be improved slightly.? Material costs for the synthetic EA/TEF inserts were less than $2 U.S. per insert. Conclusions: We have successfully created a low-cost synthetic EA/TEF tissue insert for use in a neonatal thoracoscopic EA/TEF repair simulator. Analysis of the participants' ratings of the synthetic EA/TEF simulation model indicates that it has value and can be used to train pediatric surgeons, especially those early in their learning curve, to begin to perform a thoracoscopic EA/TEF repair. Areas for model improvement were identified, and these areas will be the focus for future modifications to the synthetic EA/TEF repair simulator.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/140150/1/lap.2014.0370.pd
Preliminary Evaluation of a Novel Thoracoscopic Infant Lobectomy Simulator
Purpose: Thoracoscopic lobectomy in infants requires advanced minimally invasive skills. Simulation-based education has the potential to improve complex procedural skills without exposing the patient to undue risks. The study purposes were (1) to create a size-appropriate infant lobectomy simulator and (2) to evaluate validity evidence to support or refute its use in surgical education. Materials and Methods: In this Institutional Review Board-exempt study, a size-appropriate rib cage for a 3-month-old infant was created. Fetal bovine tissue completed the simulator. Thirty-three participants performed the simulated thoracoscopic lobectomy. Participants completed a self-report, 26-item instrument consisting of 25 4-point rating scales (from 1=not realistic to 4=highly realistic) and a one 4-point Global Rating Scale. Validity evidence relevant to test content and response processes was evaluated using the many-facet Rasch model, and evidence of internal structure (inter-item consistency) was estimated using Cronbach's alpha. Results: Experienced surgeons (observed average=3.6) had slightly higher overall rating than novice surgeons (observed average=3.4, P=.001). The highest combined observed averages were for the domain Physical Attributes (3.7), whereas the lowest ratings were for the domains Realism of Experience and Ability to Perform Tasks (3.4). The global rating was 2.9, consistent with ?this simulator can be considered for use in infant lobectomy training, but could be improved slightly.? Inter-item consistency for items used to evaluate the simulator's quality was high (Ī±=0.90). Conclusions: With ratings consistent with high physical attributes and realism, we successfully created an infant lobectomy simulator, and preliminary evidence relevant to test content, response processes, and internal structure was supported. Participants rated the model as realistic, relevant to clinical practice, and valuable as a learning tool. Minor improvements were suggested prior to its full implementation as an educational and testing tool.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/140149/1/lap.2014.0364.pd
Substrate Binding Regulates Redox Signaling in Human DNA Primase
Generation of daughter strands during DNA replication requires the action of DNA primase to synthesize an initial short RNA primer on the single-stranded DNA template. Primase is a heterodimeric enzyme containing two domains whose activity must be coordinated during primer synthesis: an RNA polymerase domain in the small subunit (p48) and a [4Fe4S] cluster-containing C-terminal domain of the large subunit (p58C). Here we examine the redox switching properties of the [4Fe4S] cluster in the full p48/p58 heterodimer using DNA electrochemistry. Unlike with isolated p58C, robust redox signaling in the primase heterodimer requires binding of both DNA and NTPs; NTP binding shifts the p48/p58 cluster redox potential into the physiological range, generating a signal near 160 mV vs NHE. Preloading of primase with NTPs enhances catalytic activity on primed DNA, suggesting that primase configurations promoting activity are more highly populated in the NTP-bound protein. We propose that p48/p58 binding of anionic DNA and NTPs affects the redox properties of the [4Fe4S] cluster; this electrostatic change is likely influenced by the alignment of primase subunits during activity because the configuration affects the [4Fe4S] cluster environment and coupling to DNA bases for redox signaling. Thus, both binding of polyanionic substrates and configurational dynamics appear to influence [4Fe4S] redox signaling properties. These results suggest that these factors should be considered generally in characterizing signaling networks of large, multisubunit DNA-processing [4Fe4S] enzymes
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