Organizational Unit:
College of Sciences
College of Sciences
Permanent Link
Research Organization Registry ID
Description
Previous Names
Parent Organization
Parent Organization
Includes Organization(s)
Organizational Unit
Organizational Unit
Organizational Unit
Organizational Unit
Organizational Unit
ArchiveSpace Name Record
Publication Search Results
Now showing
1 - 10 of 428
-
ItemGene expression profiling supports the hypothesis that human ovarian surface epithelia are multipotent and capable of serving as ovarian cancer initiating cells(Georgia Institute of Technology, 2009-12-29) Bowen, Nathan J. ; Walker, L. DeEtte ; Matyunina, Lilya V. ; Logani, Sanjay ; Totten, Kimberly A. ; Benigno, Benedict B. ; McDonald, John F.Background Accumulating evidence suggests that somatic stem cells undergo mutagenic transformation into cancer initiating cells. The serous subtype of ovarian adenocarcinoma in humans has been hypothesized to arise from at least two possible classes of progenitor cells: the ovarian surface epithelia (OSE) and/or an as yet undefined class of progenitor cells residing in the distal end of the fallopian tube. Methods Comparative gene expression profiling analyses were carried out on OSE removed from the surface of normal human ovaries and ovarian cancer epithelial cells (CEPI) isolated by laser capture micro-dissection (LCM) from human serous papillary ovarian adenocarcinomas. The results of the gene expression analyses were randomly confirmed in paraffin embedded tissues from ovarian adenocarcinoma of serous subtype and non-neoplastic ovarian tissues using immunohistochemistry. Differentially expressed genes were analyzed using gene ontology, molecular pathway, and gene set enrichment analysis algorithms. Results Consistent with multipotent capacity, genes in pathways previously associated with adult stem cell maintenance are highly expressed in ovarian surface epithelia and are not expressed or expressed at very low levels in serous ovarian adenocarcinoma. Among the over 2000 genes that are significantly differentially expressed, a number of pathways and novel pathway interactions are identified that may contribute to ovarian adenocarcinoma development.
-
ItemExploring everyday privacy behaviors and misclosures(Georgia Institute of Technology, 2009-12-08) Caine, Kelly ErinnAs access to information changes with increased use of technology, privacy becomes an increasingly prominent issue among technology users. Privacy concerns should be taken seriously because they influence system adoption, the way a system is used, and may even lead to system disuse. Threats to privacy are not only due to traditional security and privacy issues; human factors issues such as unintentional disclosure of information also influence the preservation of privacy in technology systems. A dual pronged approach was used to examine privacy. First, a broad investigation of younger and older adults' privacy behaviors was conducted. The goal of this study was to gain a better understanding of privacy across technologies, to discover the similarities, and identify the differences in what privacy means across contexts as well as provide a means to evaluate current theories of privacy. This investigation resulted in a categorization of privacy behaviors associated with technology. There were three high level privacy behavior categories identified: avoidance, modification, and alleviatory behavior. This categorization furthers our understanding about the psychological underpinnings of privacy concerns and suggests that 1) common privacy feelings and behaviors exist across people and technologies and 2) alternative designs which consider these commonalities may increase privacy. Second, I examined one specific human factors issue associated with privacy: disclosure error. This investigation focused on gaining an understanding of how to support privacy by preventing misclosure. A misclosure is an error in disclosure. When information is disclosed in error, or misclosed, privacy is violated in that information not intended for a specific person(s) is nevertheless revealed to that person. The goal of this study was to provide a psychological basis for design suggestions for improving privacy in technology which was grounded in empirical findings. The study furthers our understanding about privacy errors in the following ways: First, it demonstrates for the first time that both younger and older adults experience misclosures . Second, it suggests that misclosures occur even when technology is very familiar to the user. Third, it revealed that some misclosure experiences result in negative consequences, suggesting misclosure is a potential threat to privacy. Finally, by exploring the context surrounding each reported misclosure, I was able to propose potential design suggestions that may decrease the likelihood of misclosure.
-
ItemAsymptotic Almost Periodicity of Scalar Parabolic Equations with Almost Periodic Time Dependence(Georgia Institute of Technology, 2009-12-07) Shen, Wenxian ; Yi, Yingfei
-
ItemDynamics of Almost Periodic Scalar Parabolic Equations(Georgia Institute of Technology, 2009-12-07) Shen, Wenxian ; Yi, Yingfei
-
ItemRandom Restarts in Global Optimization(Georgia Institute of Technology, 2009-12-07) Hu, X. ; Shonkwiler, Ronald W. ; Spruill, Marcus C.In this article we study stochastic multistart methods for global optimization, which combine local search with random initialization, and their parallel implementations. It is shown that in a minimax sense the optimal restart distribution is uniform. We further establish the rate of decrease of the ensemble probability that the global minimum has not been found by the nth iteration. Turning to parallelization issues, we show that under independent identical processing (iip), exponential speedup in the time to hit the goal bin normally results. Our numerical studies are in close agreement with these finndings.
-
ItemA Curious Binomial Identity(Georgia Institute of Technology, 2009-12-07) Calkin, Neil J.In this note we shall prove the following curious identity of sums of powers of the partial sum of binomial coefficients.
-
ItemConverse Poincaré Type Inequalities for Convex Functions(Georgia Institute of Technology, 2009-12-07) Bobkov, S. G. ; Houdré, ChristianConverse Poincaré type inequalities are obtained within the class of smooth convex functions. This is, in particular, applied to the double exponential distribution.
-
ItemEffects of Word Replacement on Juror Perceptions and Guilt Ratings During a Criminal Trial(Georgia Institute of Technology, 2009-12) Coons, Courtney A.This research was performed with the aim of improving the body of knowledge on juror perceptions during criminal trials. Three juries were formed of men and women at least 18 years old. The juries witnessed key excerpts of a criminal trial, either edited or unedited for content and then placed in a room for deliberation. Deliberations were videotaped and the juries had up to 45 minutes to return a verdict. Two juries viewed the content-edited trials, removing all instances of the word "rape". One of these juries was told of the editing, the other was not. After all juries had returned a verdict, each individual juror was asked to take an exit survey inquiring about their particular perceptions of the trial, and their personal conviction of guilt or lack thereof. All juries returned a verdict of 'not guilty' , however the exit surveys showed that more than 50% of the jurors that viewed the un-edited trial had an abiding conviction of guilt but rendered a not guilty verdict based on a lack of physical evidence. The content-edited conditions, however, had only 3 people between them that believed the defendant to be guilty of the crime of rape.
-
ItemAmino Acid Profiling by Reactive Desorption Electrospray Ionization Tandem Mass Spectrometry (DESI-MS/MS)(Georgia Institute of Technology, 2009-12) Rizzo, David G.Desorption electrospray ionization mass spectrometry (DESI MS) has gained significant recognition over the past few years because of its simplicity and rapid throughput capabilities, allowing for the direct analysis of samples with a wide variety of sizes, shapes, and chemistries. Addition of various reagents into the DESI spray solvent enables atmospheric pressure ion molecule reactions between these reagents in the charged micro droplets and analyte molecules on the sample surface affording improved selectivity and sensitivity in some cases. Presented is a rapid screening method for amino acids (aas) based on reactive DESI. Amino acids have been shown to play key roles in the regulation of cellular processes. They are also particularly vital in the determination of metabolic disorders such as phenylketonurea, homocystinuria, and tyrosinemia. The most specific and reliable methods for diagnosing these disorders are based on the determination of aas in body fluids using methodologies such as gas/liquid chromatography, tandem MS, and various combinations thereof. However, these methods are usually time-consuming, increasing the time physicians wait before administering treatment or regulating the diet of diseased infants. The reactive DESI approach presented here is based on the formation of stable noncovalent complexes between alpha-cyclodextrin (dissolved in the spray solvent) and amino acids present in the sample affording a selective method for their detection. However, the selectivity and sensitivity of screening for aas was improved by performing the MS analysis in the multiple reaction monitoring mode when using a quadrupole ion trap or by the precursor ion scan when using a triple quadrupole MS instrument, affording an average twenty-five times sensitivity improvement compared to analysis in full scan mode. The observation of similar complexes with various carboxylic acids including formic acid and acetic acid, and evidence from tandem MS experiments indicate that amino acid:alpha-cyclodextrin complexation reactions occur by hydrogen bonding interaction with carboxyl group of the aas. The specificity and sensitivity provided by this approach seems very promising for applications in the rapid screening of aas directly from body fluids including urine and plasma for amino acid disorders in a clinical setting.
-
ItemTraining Novices on Hierarchical Task Analysis(Georgia Institute of Technology, 2009-12) Felipe, SarahThe training of a complex task such as task analysis is an area that very few have explored. This study examines how different training methods affect knowledge acquisition, focusing on content learned and errors made by novices in the initial phase of learning of Hierarchical Task Analysis (HTA). Three types of declarative instructions were compared: procedures, decision/actions, and concept map, which were representative of different types of diagrams (matrix, network, hierarchy). Participants were assigned to one of the training conditions and instructed to perform task analyses of five different tasks (making a piece of toast, making a cup of coffee, painting a door, making a phone call, and making Vetkoek - a South African main course). Questionnaire data (declarative knowledge) and task analyses (procedural knowledge) were coded on five criteria: hierarchical representation, stating high-level goal, stating plan, stating subgoals, and satisfaction criteria. Results indicated that participants identified some criteria (goals, subgoals) more often than others as being representative of HTA (hierarchical representation). Furthermore, the nature of the task had a greater effect on the knowledge acquired about HTA than the differences in training material at this early stage of learning. During initial training of HTA it is important that more detailed instruction materials be distributed to allow for greater understanding of HTA. This study informs research about various types of diagrams and also adds to the literature on training HTA.