Physical Sciences and Mathematics Commons^™

A Clustering Approach For Optimizing Beam Angles In Imrt Planning, Gino J. Lim, Allen Holder, Josh Reese

Mathematical Sciences Technical Reports (MSTR)

In this paper we introduce a p-median problem based clustering heuristic for selecting efficient beam angles for intensity-modulated radiation therapy. The essence of the method described here is the clustering of beam angles according to probability that an angle will be observed in the final solution and similarities among different angles and the selection of a representative angle from each of the p resulting cluster cells. We conduct experiments using several combinations of modeling parameters to find the conditions where the heuristic best performs. We found a combination of such parameters that outperformed all other parameters on three of the …

Complex Adaptive Systems As A Model For Evaluating Organisational Change Caused By The Introduction Of Health Information Systems, Kieren Diment Mr, Ping Yu, K. Garrety

Faculty of Informatics - Papers (Archive)

This paper documents the preliminary development of a framework for evaluating organisational change processes during the implementation of an electronic nursing documentation system in residential aged care facilities. It starts with a brief outline of organisational change processes. This is followed by a more detailed exposition of the principles underlying complex adaptive systems (CAS) theory, where we explain how mathematical concepts can be used to illuminate qualitative research approaches. Finally we present some preliminary findings on the facilitators and barriers for the introduction of the electronic documentation system, explained with reference to the CAS theory, based on analysis of interviews …

Spiroadamantyl 1,2,4-Trioxolane, 1,2,4-Trioxane, And 1,2,4-Trioxepane Pairs: Relationship Between Peroxide Bond Iron(Ii) Reactivity, Heme Alkylation Efficiency, And Antimalarial Activity, Xiaofang Wang, Darren J. Creek, Yuxiang Dong, Jacques Chollet, Christian Scheurer, Sergio Wittlin, Susan A. Charman, Patrick H. Dussault, James K. Wood, Jonathan L. Vennerstrom

Chemistry Faculty Publications

These data suggest that iron(II) reactivity for a set of homologous spiroadamantyl 1,2,4-trioxolane, 1,2,4-trioxane, and 1,2,4-trioxepane peroxide heterocycles is a necessary, but insufficient, property of animalarial peroxides. Heme alkylation efficiency appears to give a more accurate prediction of antimalarial activity than FeSO4-mediated reaction rates, suggesting that antimalarial activity is not merely dependent on peroxide bond cleavage, but also on the ability of reactive intermediates to alkylate heme or other proximal targets.

The Effects Of Physical Activity And Nutrient Intake On The Risk Of Hip Fracture : Results From The Adventist Health Study-2, Wen-Ling Liao

Loma Linda University Electronic Theses, Dissertations & Projects

This is a two year of follow up study of Adventist Health Study-2 (AHS-2). We assessed the association between physical activity, nutrient intake and risk of hip fracture among peri- and post menopausal Caucasian women using unconditional logistic regression models. All subjects completed a lifestyle questionnaire which including information of physical activity and frequency and portion size of food intake at enrollment into the study (2002-2007). The “Bi-Annual Hospitalization History” questionnaire which included a question about hip fractures due to minor trauma/falls was sent to subjects approximately two years after enrollment, with a response rat of 82.84%. In this cohort, …

Multiple Loci Within The Major Histocompatibility Complex Confer Risk Of Psoriasis, Bing-Jian Feng, Liang-Dan Sun, Razieh Soltani-Arabshahi, Anne M. Bowcock, Rajan P. Nair, Philip Stuart, James T. Elder, Steven J. Schrodi, Ann B. Begovich, Goncalo R. Abecasis, Xue-Jun Zhang, Kristina P. Callis Duffin, Gerald G. Krueger, David E. Goldgar

Steven J Schrodi

Psoriasis is a common inflammatory skin disease characterized by thickened scaly red plaques. Previously we have performed a genome-wide association study (GWAS) on psoriasis with 1,359 cases and 1,400 controls, which were genotyped for 447,249 SNPs. The most significant finding was for SNP rs12191877, which is in tight linkage disequilibrium with HLA-Cw*0602, the consensus risk allele for psoriasis. However, it is not known whether there are other psoriasis loci within the MHC in addition to HLA-C. In the present study, we searched for additional susceptibility loci within the human leukocyte antigen (HLA) region through in-depth analyses of the GWAS data; …

E-Science @ Umass: Anticipating And Supporting E-Science Activities At The University Of Massachusetts, Maxine G. Schmidt, Rebecca Reznik-Zellen

Maxine G Schmidt

In March of 2008 an Ad Hoccommittee of Science Librarians from the University of Massachusetts Five Campus System convened to discuss the challenges of e-science and prepare the Libraries for their role in e-science initiatives. Three primary outcomes intended to support e-science activities emerged from the work of the Ad Hoc committee.

Santa Clara Magazine, Volume 51 Number 1, Summer 2009, Santa Clara University

Santa Clara Magazine

14 - INAUGURATING PRESIDENT ENGH By Steven Boyd Saum. On the occasion, a ringing challenge from President Engh: Make SCU a champion for environmental justice. Read the speech and see the photos.

22 - SAVING BOUNTY By Elizabeth Svoboda. Our food-safety system is in shambles, but there are ways to make it work again. For one answer, look to your leafy greens.

28 - CAN WE SOLVE HUNGER IN OUR LIFETIME? BY Dashka Slater. Here are six ideas that, practiced together, will make a difference.

34 - ALTERNATIVE REALITY: "WORLD WITHOUT OIL" By Paul Totah '79. Alternate reality games can …

Summer 2009 Research Symposium Abstract Book, Trinity College

Science Symposia Abstracts

Summer 2009 volume of abstracts for science research projects conducted by Trinity College students.

Brain Tumor Progression Assessment Using Multiple Mri Volumes, Yufei Shen

Electrical & Computer Engineering Theses & Dissertations

Predicting and assessing tumor progression is important in brain tumor treatment. We attempt to use machine learning techniques to achieve consistency in assessing brain tumor progression. This thesis presents a prediction method of brain tumor progression by exploring a large MR database, which contains two patients ' complete records covering all their visits in the past two years. All ten MRI series, namely, apparent diffusion coefficient (ADC) , diffusion tensor imaging (DTI) , fractional anisotropy (FA), fluid attenuated inversion recovery (FLAIR), max eigenvalue (MAX), mid eigenvalue (MID), min eigenvalue (MIN) , post-contrast T₁-weighted, T₁- weighted, and …

A Spatio-Temporal Approach For Estimating Chronic Effects Of Air Pollution, Sonja Greven, Francesca Dominici, Scott L. Zeger

Johns Hopkins University, Dept. of Biostatistics Working Papers

Estimating the health risks associated with air pollution exposure is of great importance in public health. In air pollution epidemiology, two study designs have been used mainly. Time series studies estimate acute risk associated with short-term exposure. They compare day-to-day variation of pollution concentrations and mortality rates, and have been criticized for potential confounding by time-varying covariates. Cohort studies estimate chronic effects associated with long-term exposure. They compare long-term average pollution concentrations and time-to-death across cities, and have been criticized for potential confounding by individual risk factors or city-level characteristics.

We propose a new study design and a statistical model, …

Spatial Cluster Detection For Repeatedly Measured Outcomes While Accounting For Residential History, Andrea J. Cook, Diane Gold, Yi Li

Harvard University Biostatistics Working Paper Series

No abstract provided.

Spatial Cluster Detection For Weighted Outcomes Using Cumulative Geographic Residuals, Andrea J. Cook, Yi Li, David Arterburn, Ram C. Tiwari

Harvard University Biostatistics Working Paper Series

No abstract provided.

Residential Modifications And Decline In Physical Function Among Community-Dwelling Older Ad, Sze Yan Liu, Kate L. Lapane

Department of Public Health Scholarship and Creative Works

Purpose: The purpose of this study is to quantify the effect of residential modification on decreasing the risk of physical function decline in 2 years.

Design: Cohort study using propensity scores method to control for baseline differences between individuals with residential modifications and those without residential modifications.

Participants: Participants (N = 9,447) were from the Second Longitudinal Study on Aging, a nationally representative sample of the civilian noninstitutionalized population, aged 70 years and older in the United States at the time of baseline interview in 1994-1995.

Methods: Participants self-reported residential modifications at baseline (e.g., railings, bathroom modifications). The decline in …

A Machine-Learning Algorithm For Estimating And Ranking The Impact Of Environmental Risk Factors In Exploratory Epidemiological Studies, Jessica G. Young, Alan E. Hubbard, B Eskenazi, Nicholas P. Jewell

U.C. Berkeley Division of Biostatistics Working Paper Series

No abstract provided.

Anthropometric Parameters Of Under-Five Years Old Children With Different Dietary Habits In Ukambani Region : A Study In Eastern Rural Kenya, Hellen M. Ndiku

Loma Linda University Electronic Theses, Dissertations & Projects

The objective of this descriptive cross sectional study was to assess dietary intake and nutritional status of children under-five years in two rural sites of Eastern Kenya where the staple cereals may differ. A modified rapid, knowledge, practice and coverage (KPC) questionnaire and a 24-hr dietary recall form were used to collect the data. A total of 403 households were surveyed from four randomly selected divisions. This yielded 629 surrogate 24-hr dietary recalls of children < 5 years with 314 from Mwingi district and 315 from Makueni district (49 % boys and 51 % girls).

Statistical analysis was done using SPSS and SAS. Comparison of means was done using t- test and chi square was used for proportions. The 24-hr …

The Effects Of A Psychoneuroimmunology Based Lifestyle Intervention In Modifying The Progression Of Major Depression In Clinically Depressed Adults, Ruth A. Tanyi

Loma Linda University Electronic Theses, Dissertations & Projects

Chronic stress can lead to poorly controlled upsurges of cortisol and dysregulation of the hypothalamic pituitary-adrenal axis, thereby contributing to major depression. Hence, researchers have begun to examine the effects of individual psychoneuroimmunology (PNI) interventions and their impact on modifying stress and depression. However, there is a lack of studies that have examined the composite effect(s) of a PNI-based lifestyle intervention and major depression. Thus, this randomized interventional study examined the composite effect(s) of a PNI-based lifestyle intervention: combined progressive muscle relaxation and spiritual guided imagery and humor as an adjunct therapy to modifying the progression of depression. Participants were …

Modeling And Analysis Of The Spread Of Japanese Encephalitis With Environmental Effects, Ram Naresh, Surabhi Pandey

Applications and Applied Mathematics: An International Journal (AAM)

A nonlinear mathematical model for the spread of Japanese Encephalitis, caused by infected mosquito feeding on susceptible human population incorporating demographic and environmental factors is proposed and analyzed. In the modeling process, it is assumed that the growth rates of reservoir animal population and vector mosquito population are enhanced due to environmental discharges caused by human population related factors. The model is analyzed by stability theory of differential equations and computer simulation. Both the disease-free and the endemic equilibria are found and their stability is investigated. It is found that whenever the disease-free equilibrium is locally asymptotically stable, the endemic …

Confidence Intervals For The Ratio Of Two Exponential Means With Applications To Quality Control, James Albert Polcer,Iii

Student Research Conference Select Presentations

We considered the problem of statistical quality control based on the ratio of two population means. We restrict the discussion for two exponential rates, which are commonly used for modeling failure times of components, machines, or systems. Closed form expressions via the moment generation function (MGF) technique will be presented, and numerical examples will be shown using engineering data sets.

Mnte-2-Pyp And Radiation In A Prostate Cancer Model: Implications For Radiotherapy, Adeola Y. Makinde

Loma Linda University Electronic Theses, Dissertations & Projects

A major limitation of successful radiation therapy in cancer treatment is the increase in normal tissue damage as higher doses are used to achieve greater tumor destruction. Radiation dose optimization in cancer therapy requires achieving maximum tumor destruction with minimal damage to normal tissue Antioxidants have been shown to protect normal tissues against radiation damage, as radiation-induced tissue damage results predominantly from reactive oxygen species that directly damage cellular components. However, for effective use as normal tissue radioprotectants in radiotherapy, these antioxidants must not protect the tumors. Mn (III) tetrakis (N-ethylpyridinium-2-yl) porphyrin (MnTE-2-PyP) is a metalloporphyrin antioxidant that has been …

Identifying Biomarkers For Resistance To Novel Cisplatin Analogues In Human Lung, Breast And Prostate Cancers, Becky Michelle Hess

UNLV Theses, Dissertations, Professional Papers, and Capstones

Cisplatin is a common therapeutic agent used in cancer treatment. Unfortunately, resistance to cisplatin in addition to severe side effects limits its use in cancer treatment. Two novel cisplatin analogues, 4DB and 4TB were shown to have varying cytotoxicity in lung, breast and prostate cancer cells. The hypothesis for this study states that the differences in 4DB and 4TB cytotoxicity among different tissue types is due to the type and efficiency of DNA repair mechanisms involved in response to these drugs.

To test the hypothesis, proteins involved in the rate limiting step of nucleotide excision repair (NER) and mismatch repair …

Regression When The Predictors Are Images, Philip T. Reiss

Philip T. Reiss

No abstract provided.

Protecting Walden Pond: A Step Towards Defending Ordinary Nature In The United States, Jessie L. Magee

Student Research Conference Select Presentations

No abstract provided.

Faulkner The Humanist: How His Nobel Prize Acceptance Speech Changed How We Interpret "Barn Burning", Jessie L. Magee

Student Research Conference Select Presentations

No abstract provided.

2009 - The Fourteenth Annual Symposium Of Student Scholars

Symposium of Student Scholars Program Books

The full program book from the Fourteenth Annual Symposium of Student Scholars, held on April 13, 2009. Includes abstracts from the presentations and posters.

2009 Annual Research Symposium Abstract Book, Trinity College

Science Symposia Abstracts

2009 annual volume of abstracts for science research projects conducted by students at Trinity College.

Volume 02, Joseph A. Mann, Kathryn J. Greenly, Scott E. Jenkins, Andrew E. Puckette, Daniel M. Honey, Jeffery P. Ravenhorst, Jamie Elizabeth Mesrobian, Thomas Scott, Jay Crowell, Sarah Spangenberg, Amy S. Eason, Kenny Wolfe, Liz Hale, Rachel Bouchard, Will Semonco, Carley York, Ryan Higgenbothom, Adrienne Heinbaugh, Melissa Dorton, Madeline Hunter, June Ashmore, Clark Barkley, Jay Haley

Incite: The Journal of Undergraduate Scholarship

Introduction from Dean Dr. Charles Ross

Mike's Nite: New Jazz for an Old Instrument by Joseph A. Mann

Investigation of the use of Cucumis Sativus for Remediation Of Chromium from Contaminated Environmental Matrices: An Interdisciplinary Instrumental Analysis Project by Kathryn J. Greenly, Scott E. Jenkins, and Andrew E. Puckette

Development of GC-MS and Chemometric Methods for the Analysis of Accelerants in Arson Cases by Scott Jenkins

Building and Measuring Scalable Computing Systems by Daniel M. Honey and Jeffery P. Ravenhorst

Nomini Hall: A Case Study in the Use of Archival Resources as Guides for Excavation at An Archaeological Site by …

La Calidad Del Agua Potable En Arica, Con Respecto A La Salud, Emily Lubell

Independent Study Project (ISP) Collection

Water is essential to sustain life, and the availability of safe drinking water is a concern throughout the world. This study examines the potential negative health effects related to drinking the potable water in Arica, Chile. It also looks at who has access to purified water. This study was implemented over a span of four weeks in which information was collected from different local resources including, the potable water distributor, private water vendors, professors, and public health service workers. In comparison with 2001, 2009 levels of boron, total hardness and total dissolved solids are higher in concentration. In both 2001 …

Smoothing Parameter Selection For A Class Of Semiparametric Linear Models, Philip T. Reiss, R. Todd Ogden

Philip T. Reiss

Spline-based approaches to nonparametric and semiparametric regression, as well as to regression of scalar outcomes on functional predictors, entail choosing a parameter controlling the extent to which roughness of the fitted function is penalized. In this paper we demonstrate that the equations determining two popular methods for smoothing parameter selection, generalized cross-validation and restricted maximum likelihood, share a similar form that allows us to prove several results common to both, and to derive a condition under which they yield identical values. These ideas are illustrated by application of functional principal component regression, a method for regressing scalars on functions, to …

The Importance Of Scale For Spatial-Confounding Bias And Precision Of Spatial Regression Estimators, Christopher J. Paciorek

Harvard University Biostatistics Working Paper Series

Increasingly, regression models are used when residuals are spatially correlated. Prominent examples include studies in environmental epidemiology to understand the chronic health effects of pollutants. I consider the effects of residual spatial structure on the bias and precision of regression coefficients, developing a simple framework in which to understand the key issues and derive informative analytic results. When the spatial residual is induced by an unmeasured confounder, regression models with spatial random effects and closely-related models such as kriging and penalized splines are biased, even when the residual variance components are known. Analytic and simulation results show how the bias …

Smoking Enhances Risk For New External Genital Warts In Men, Dorothy J. Wiley, David Elashoff, Emmanuel V. Masongsong, Diane M. Harper

Dartmouth Scholarship

Repeat episodes of HPV-related external genital warts reflect recurring or new infections. No study before has been sufficiently powered to delineate how tobacco use, prior history of EGWs and HIV infection affect the risk for new EGWs. Behavioral, laboratory and examination data for 2,835 Multicenter AIDS Cohort Study participants examined at 21,519 semi-annual visits were evaluated. Fourteen percent (391/2835) of men reported or were diagnosed with EGWs at 3% (675/21,519) of study visits. Multivariate analyses showed smoking, prior episodes of EGWs, HIV infection and CD4+ T-lymphocyte count among the infected, each differentially influenced the risk for new EGWs.