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Search Results: 1 - 10 of 259145 matches for " Hannah P. Yang "
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Genetic Variation on 9p22 Is Associated with Abnormal Ovarian Ultrasound Results in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial
Nicolas Wentzensen,Amanda Black,Kevin Jacobs,Hannah P. Yang,Christine D. Berg,Neil Caporaso,Ulrike Peters,Lawrence Ragard,Saundra S. Buys,Stephen Chanock,Patricia Hartge
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0021731
Abstract: A recent ovarian cancer genome-wide association study (GWAS) identified a locus on 9p22 associated with reduced ovarian cancer risk. The single nucleotide polymorphism (SNP) markers localize to the BNC2 gene, which has been associated with ovarian development.
How to Stay Healthy While Studying Abroad: Development of an Electronic Magazine for College Students  [PDF]
Hannah M. Lightcap, Marie Fanelli Kuczmarski, Lisa P. Chieffo
Creative Education (CE) , 2016, DOI: 10.4236/ce.2016.715206
Abstract: Increasing numbers of US college students are participating in travel study programs. As part of their pre-departure preparation, institutions provide orientation materials covering a range of topics. These materials typically cover such health-related topics as immunizations, sun safety, psychological distress, personal assault, and water quality. However, comprehensive coverage of strategies to ensure optimal physical wellness while traveling has been overlooked. This article describes the development and evaluation of an electronic (e) magazine entitled, “How to Stay Healthy While Studying Abroad”. This e-magazine not only explains the importance of physical activity, food and beverage practices, sleep, and stress and time management, but also offers tips for achieving wellness during travel. The primary objective of the study was to evaluate the usefulness of the e-magazine. The secondary objective was to enhance the content of the guide based on an assessment of students’ attitudes, perceptions and behaviors related to wellness pre- and post-participation in travel study programs. Prior to travel over 70% of students felt they would be able to engage in healthful eating and physical activity. Fifty-two percent of students found it challenging to eat healthfully and be physically active on their travel study programs. The vast majority of students (87%) reported that they found the guide helpful in promoting healthful behaviors. Hydration, health during travel, and getting enough sleep were the top three e-magazine areas utilized. Self-motivation, social support and tips within How to Stay Healthy While Studying Abroad were the top three factors which contributed to achieving physical wellness. The guide was considered useful based on the findings and evidenced by students’ recommendations that the guide be shared with all university students.
The Student Well-Being Process Questionnaire (Student WPQ)  [PDF]
Gary M. Williams, Hannah Pendlebury, Kai Thomas, Andrew P. Smith
Psychology (PSYCH) , 2017, DOI: 10.4236/psych.2017.811115
Abstract: Recent research has used short questionnaires based on single item versions of psychosocial concepts to assess well-being. This has largely been confined to occupational samples and the present article describes the extension of this process to university students. The Student Well-being Process Questionnaire (Student WPQ) was used to examine predictors of positive well-being, negative mental health and cognitive function. An online survey was used with 478 first and second year undergraduates as participants. Regression analyses showed that positive well-being (e.g. happiness, positive affect and life satisfaction) was predicted by positive personality (high optimism, self-esteem and self-efficacy), high social support and low stressors and low negative coping scores. Negative outcomes (e.g. perceived stress, anxiety and depression) were predicted by high stressor, coping and conscientiousness scores, and low positive personality and social support scores. Cognitive problems were predicted by high stressor and negative coping scores and low positive personality scores. A MANOVA showed that there were no significant interactions between the predictor variables. The best predictor of all outcomes was a combined score including all predictor variables. Overall, the present study shows that the Student WPQ can provide useful information on predictors of different aspects of well-being. Future research can include additional potential predictors and other outcomes to determine whether other factors are significant when established predictors are adjusted for.
Detection of Somatic Mutations by High-Resolution DNA Melting (HRM) Analysis in Multiple Cancers
Jesus Gonzalez-Bosquet,Jacob Calcei,Jun S. Wei,Montserrat Garcia-Closas,Mark E. Sherman,Stephen Hewitt,Joseph Vockley,Jolanta Lissowska,Hannah P. Yang,Javed Khan,Stephen Chanock
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0014522
Abstract: Identification of somatic mutations in cancer is a major goal for understanding and monitoring the events related to cancer initiation and progression. High resolution melting (HRM) curve analysis represents a fast, post-PCR high-throughput method for scanning somatic sequence alterations in target genes. The aim of this study was to assess the sensitivity and specificity of HRM analysis for tumor mutation screening in a range of tumor samples, which included 216 frozen pediatric small rounded blue-cell tumors as well as 180 paraffin-embedded tumors from breast, endometrial and ovarian cancers (60 of each). HRM analysis was performed in exons of the following candidate genes known to harbor established commonly observed mutations: PIK3CA, ERBB2, KRAS, TP53, EGFR, BRAF, GATA3, and FGFR3. Bi-directional sequencing analysis was used to determine the accuracy of the HRM analysis. For the 39 mutations observed in frozen samples, the sensitivity and specificity of HRM analysis were 97% and 87%, respectively. There were 67 mutation/variants in the paraffin-embedded samples, and the sensitivity and specificity for the HRM analysis were 88% and 80%, respectively. Paraffin-embedded samples require higher quantity of purified DNA for high performance. In summary, HRM analysis is a promising moderate-throughput screening test for mutations among known candidate genomic regions. Although the overall accuracy appears to be better in frozen specimens, somatic alterations were detected in DNA extracted from paraffin-embedded samples.
Clinical and Pathological Heterogeneity of Cervical Intraepithelial Neoplasia Grade 3
Hannah P. Yang, Rosemary E. Zuna, Mark Schiffman, Joan L. Walker, Mark E. Sherman, Lisa M. Landrum, Katherine Moxley, Michael A. Gold, S. Terence Dunn, Richard A. Allen, Roy Zhang, Rodney Long, Sophia S. Wang, Nicolas Wentzensen
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0029051
Abstract: Objective Cervical intraepithelial neoplasia grade 3 (CIN3), the immediate cervical cancer precursor, is a target of cervical cancer prevention. However, less than half of CIN3s will progress to cancer. Routine treatment of all CIN3s and the majority of CIN2s may lead to overtreatment of many lesions that would not progress. To improve our understanding of CIN3 natural history, we performed a detailed characterization of CIN3 heterogeneity in a large referral population in the US. Methods We examined 309 CIN3 cases in the SUCCEED, a large population-based study of women with abnormal cervical cancer screening results. Histology information for 12 individual loop electrosurgical excision procedure (LEEP) segments was evaluated for each woman. We performed case-case comparisons of CIN3s to analyze determinants of heterogeneity and screening test performance. Results CIN3 cases varied substantially by size (1–10 LEEP segments) and by presentation with concomitant CIN2 and CIN1. All grades of CINs were equally distributed over the cervical surface. In half of the women, CIN3 lesions were found as multiple distinct lesions on the cervix. Women with large and solitary CIN3 lesions were more likely to be older, have longer sexual activity span, and have fewer multiple high risk HPV infections. Screening frequency, but not HPV16 positivity, was an important predictor of CIN3 size. Large CIN3 lesions were also characterized by high-grade clinical test results. Conclusions We demonstrate substantial heterogeneity in clinical and pathological presentation of CIN3 in a US population. Time since sexual debut and participation in screening were predictors of CIN3 size. We did not observe a preferential site of CIN3 on the cervical surface that could serve as a target for cervical biopsy. Cervical cancer screening procedures were more likely to detect larger CIN3s, suggesting that CIN3s detected by multiple independent diagnostic tests may represent cases with increased risk of invasion.
The spectral difference between solar flare HXR coronal and footpoint sources due to wave-particle interactions
I. G. Hannah,E. P. Kontar
Physics , 2011, DOI: 10.1051/0004-6361/201015710
Abstract: Investigate the spatial and spectral evolution of hard X-ray (HXR) emission from flare accelerated electron beams subject to collisional transport and wave-particle interactions in the solar atmosphere. We numerically follow the propagation of a power-law of accelerated electrons in 1D space and time with the response of the background plasma in the form of Langmuir waves using the quasilinear approximation.}{We find that the addition of wave-particle interactions to collisional transport for a transient initially injected electron beam flattens the spectrum of the footpoint source. The coronal source is unchanged and so the difference in the spectral indices between the coronal and footpoint sources is \Delta \gamma > 2, which is larger than expected from purely collisional transport. A steady-state beam shows little difference between the two cases, as has been previously found, as a transiently injected electron beam is required to produce significant wave growth, especially at higher velocities. With this transiently injected beam the wave-particle interactions dominate in the corona whereas the collisional losses dominate in the chromosphere. The shape of the spectrum is different with increasing electron beam density in the wave-particle interaction case whereas with purely collisional transport only the normalisation is changed. We also find that the starting height of the source electron beam above the photosphere affects the spectral index of the footpoint when Langmuir wave growth is included. This may account for the differing spectral indices found between double footpoints if asymmetrical injection has occurred in the flaring loop.
Multi-thermal dynamics and energetics of a coronal mass ejection in the low solar atmosphere
I. G. Hannah,E. P. Kontar
Physics , 2012, DOI: 10.1051/0004-6361/201219727
Abstract: The aim of this work is to determine the multi-thermal characteristics and plasma energetics of an eruptive plasmoid and occulted flare observed by Solar Dynamics Observatory/Atmospheric Imaging Assembly (SDO/AIA). We study an event from 03-Nov-2010 (peaking at 12:20UT in GOES soft X-rays) of a coronal mass ejection and occulted flare which demonstrates the morphology of a classic erupting flux rope. The high spatial, and time resolution, and six coronal channels, of the SDO/AIA images allows the dynamics of the multi-thermal emission during the initial phases of eruption to be studied in detail. The Differential Emission Measure (DEM) is calculated, using an optimised version of a regularized inversion method (Hannah & Kontar 2012), for each pixel across the six channels at different times, resulting in emission measure maps and movies in a variety of temperature ranges. We find that the core of the erupting plasmoid is hot (8-11, 11-14MK) with a similarly hot filamentary "stem" structure connecting it to the lower atmosphere, which could be interpreted as the current sheet in the flux rope model, though is wider than these models suggest. The velocity of the leading edge of the eruption is 597-664 km s$^{-1}$ in the temperature range $\ge$3-4MK and between 1029-1246 km s$^{-1}$ for $\le$2-3MK. We estimate the density (in 11-14 MK) of the erupting core and stem during the impulsive phase to be about $3\times10^9$ cm$^{-3}$, $6\times10^9$ cm$^{-3}$, $9\times10^8$ cm$^{-3}$ in the plasmoid core, stem and surrounding envelope of material. This gives thermal energy estimates of $5\times10^{29}$ erg, $1\times10^{29}$ erg and $2\times10^{30}$ erg. The kinetic energy for the core and envelope is slightly smaller. The thermal energy of the core and current sheet grows during the eruption, suggesting continuous influx of energy presumably via reconnection.
Differential Emission Measures from the Regularized Inversion of Hinode and SDO data
I. G. Hannah,E. P. Kontar
Physics , 2012, DOI: 10.1051/0004-6361/201117576
Abstract: We develop and apply an enhanced regularization algorithm, used in RHESSI X-ray spectral analysis, to constrain the ill-posed inverse problem that is determining the DEM from solar observations. We demonstrate this computationally fast technique applied to a range of DEM models simulating broadband imaging data from SDO/AIA and high resolution line spectra from Hinode/EIS, as well as actual active region observations with Hinode/EIS and XRT. As this regularization method naturally provides both vertical and horizontal (temperature resolution) error bars we are able to test the role of uncertainties in the data and response functions. The regularization method is able to successfully recover the DEM from simulated data of a variety of model DEMs (single Gaussian, multiple Gaussians and CHIANTI DEM models). It is able to do this, at best, to over four orders of magnitude in DEM space but typically over two orders of magnitude from peak emission. The combination of horizontal and vertical error bars and the regularized solution matrix allows us to easily determine the accuracy and robustness of the regularized DEM. We find that the typical range for the horizontal errors is $\Delta$log$T\approx 0.1 -0.5$ and this is dependent on the observed signal to noise, uncertainty in the response functions as well as the source model and temperature. With Hinode/EIS an uncertainty of 20% greatly broadens the regularized DEMs for both Gaussian and CHIANTI models although information about the underlying DEMs is still recoverable. When applied to real active region observations with Hinode/EIS and XRT the regularization method is able to recover a DEM similar to that found via a MCMC method but in considerably less computational time.
An Analysis of Gene Expression Data using Penalized Fuzzy C-Means Approach
P. K. Nizar Banu,H. Hannah Inbarani
Computer Science , 2013,
Abstract: With the rapid advances of microarray technologies, large amounts of high-dimensional gene expression data are being generated, which poses significant computational challenges. A first step towards addressing this challenge is the use of clustering techniques, which is essential in the data mining process to reveal natural structures and identify interesting patterns in the underlying data. A robust gene expression clustering approach to minimize undesirable clustering is proposed. In this paper, Penalized Fuzzy C-Means (PFCM) Clustering algorithm is described and compared with the most representative off-line clustering techniques: K-Means Clustering, Rough K-Means Clustering and Fuzzy C-Means clustering. These techniques are implemented and tested for a Brain Tumor gene expression Dataset. Analysis of the performance of the proposed approach is presented through qualitative validation experiments. From experimental results, it can be observed that Penalized Fuzzy C-Means algorithm shows a much higher usability than the other projected clustering algorithms used in our comparison study. Significant and promising clustering results are presented using Brain Tumor Gene expression dataset. Thus patterns seen in genome-wide expression experiments can be interpreted as indications of the status of cellular processes. In these clustering results, we find that Penalized Fuzzy C-Means algorithm provides useful information as an aid to diagnosis in oncology.
Ontology-based time information representation of vaccine adverse events in VAERS for temporal analysis
Tao Cui,He Yongqun,Yang Hannah,Poland Gregory A
Journal of Biomedical Semantics , 2012, DOI: 10.1186/2041-1480-3-13
Abstract: Background The U.S. FDA/CDC Vaccine Adverse Event Reporting System (VAERS) provides a valuable data source for post-vaccination adverse event analyses. The structured data in the system has been widely used, but the information in the write-up narratives is rarely included in these kinds of analyses. In fact, the unstructured nature of the narratives makes the data embedded in them difficult to be used for any further studies. Results We developed an ontology-based approach to represent the data in the narratives in a “machine-understandable” way, so that it can be easily queried and further analyzed. Our focus is the time aspect in the data for time trending analysis. The Time Event Ontology (TEO), Ontology of Adverse Events (OAE), and Vaccine Ontology (VO) are leveraged for the semantic representation of this purpose. A VAERS case report is presented as a use case for the ontological representations. The advantages of using our ontology-based Semantic web representation and data analysis are emphasized. Conclusions We believe that representing both the structured data and the data from write-up narratives in an integrated, unified, and “machine-understandable” way can improve research for vaccine safety analyses, causality assessments, and retrospective studies.
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