Data Science Commons^™

Methods And System For Equalizing Data, Jaiganesh Balakrishnan, Richard K. Martin, C. Richard Johnson Jr.

AFIT Patents

A method for equalizing data and systems utilizing the method. The method of this invention for equalizing (by shortening the channel response) data includes minimizing a function of the data and a number of equalizer characteristic parameters, where the function utilizes auto-correlation data corresponding to equalized data. Updated equalizer characteristic parameters are then obtained from the minimization and an initial set of equalizer characteristic parameters. Finally, the received data is processed utilizing the equalizer defined by the minimization. The method of this invention can be implemented in an equalizer and the equalizer of this invention may be included in a …

Downregulation Of Rap1gap Contributes To Ras Transformation, Oxana Tsygankova, Gregory V. Prendergast, Kanchan Puttaswamy, Yan Wang, Michael D. Feldman, Hongbin Wang, Marcia S. Brose, Judy L. Meinkoth

Faculty, Staff and Student Publications

Although abundant in well-differentiated rat thyroid cells, Rap1GAP expression was extinguished in a subset of human thyroid tumor-derived cell lines. Intriguingly, Rap1GAP was downregulated selectively in tumor cell lines that had acquired a mesenchymal morphology. Restoring Rap1GAP expression to these cells inhibited cell migration and invasion, effects that were correlated with the inhibition of Rap1 and Rac1 activity. The reexpression of Rap1GAP also inhibited DNA synthesis and anchorage-independent proliferation. Conversely, eliminating Rap1GAP expression in rat thyroid cells induced a transient increase in cell number. Strikingly, Rap1GAP expression was abolished by Ras transformation. The downregulation of Rap1GAP by Ras required the …

Distributed Cluster-Based Outlier Detection In Wireless Sensor Networks, Swetha Gali

Electrical & Computer Engineering Theses & Dissertations

Wireless sensor networks find several potential applications in a variety of fields, such as environmental monitoring and control, battlefields, surveillance, smart buildings, human health monitoring, etc. These sensor networks consist of a large number of very tiny, inexpensive, and low power sensor nodes, which are deployed in a variety of harsh environments that may result in the sensor data getting corrupted. It is thus critical to detect and report these abnormal values in the sensor data, in order to have a better understanding of the monitored environment. Detection of the abnormal values is of special interest for the sensor network …

Quality Of Weight Loss Advice On Internet Forums, Kevin O Hwang, Kiran Farheen, Craig W Johnson, Eric J Thomas, Ann S Barnes, Elmer V Bernstam

Faculty, Staff and Student Publications

BACKGROUND: Adults use the Internet for weight loss information, sometimes by participating in discussion forums. Our purpose was to analyze the quality of advice exchanged on these forums. METHODS: This was a retrospective analysis of messages posted to 18 Internet weight loss forums during 1 month in 2006. Advice was evaluated for congruence with clinical guidelines; potential for causing harm; and subsequent correction when it was contradictory to guidelines (erroneous) or potentially harmful. Message- and forum-specific characteristics were evaluated as predictors of advice quality and self-correction. RESULTS: Of 3368 initial messages, 266 (7.9%) were requests for advice. Of 654 provisions …

A Day In The Life Of Pubmed: Analysis Of A Typical Day's Query Log, Jorge R Herskovic, Len Y Tanaka, William Hersh, Elmer V Bernstam

Faculty, Staff and Student Publications

OBJECTIVE: To characterize PubMed usage over a typical day and compare it to previous studies of user behavior on Web search engines. DESIGN: We performed a lexical and semantic analysis of 2,689,166 queries issued on PubMed over 24 consecutive hours on a typical day. MEASUREMENTS: We measured the number of queries, number of distinct users, queries per user, terms per query, common terms, Boolean operator use, common phrases, result set size, MeSH categories, used semantic measurements to group queries into sessions, and studied the addition and removal of terms from consecutive queries to gauge search strategies. RESULTS: The size of …

Imaging Of Pulmonary Embolism And T-Pa Therapy Effects Using Mdct And Liposomal Iohexol Blood Pool Agent: Preliminary Results In A Rabbit Model, Stephen J Burke, Ananth Annapragada, Eric A Hoffman, Emmanuel Chen, Ketan B Ghaghada, Jered Sieren, Edwin J R Van Beek

Faculty, Staff and Student Publications

RATIONALE AND OBJECTIVES: Polyethylene glycol-coated liposomal blood pool contrast agents maintain contrast enhancement over several hours. This study aimed to evaluate (long-term) imaging of pulmonary arteries, comparing conventional iodinated contrast with a liposomal blood pool contrast agent. Also, visualization of the (real-time) therapeutic effects of tissue plasminogen activator (t-PA) on pulmonary embolism (PE) was attempted. MATERIALS AND METHODS: Six rabbits (weight approximately 4 kg) had autologous blood clots injected through the superior vena cava. Imaging was performed using conventional contrast (iohexol, 350 mg I/ml; GE HealthCare, Princeton, NJ) at a dose of 1400 mg I per animal, and after wash-out, …

Reducing Liver Cancer Disparities: A Community-Based Hepatitis-B Prevention Program For Asian-American Communities, Chiehwen E. Hsu, Louis Chih-Hung Liu, Hee-Soon Juon, Yu-Wen Chiu

Faculty, Staff and Student Publications

OBJECTIVES: Several Asian-American groups are at a higher risk of dying of liver diseases attributable to hepatitis-B infection. This culturally diverse community should be well informed of and protected against liver diseases. The present study assesses the knowledge of hepatitis B before and after a hepatitis-B educational program and determines the infection status of an Asian community.

METHODS: Nine Asian communities of Montgomery County, MD, enrolled in the hepatitis-B prevention program between 2005 and 2006. They attended culturally tailored lectures on prevention, completed self-administered pre- and posttests, and received blood screening for the disease.

RESULTS: More than 800 Asian Americans …

A Spatial-Temporal Approach To Surveillance Of Prostate Cancer Disparities In Population Subgroups, Chiehwen E. Hsu, Francisco Soto Mas, Jerry A. Miller, Ella T. Nkhoma

Faculty, Staff and Student Publications

BACKGROUND: Prostate cancer mortality disparities exist among racial/ethnic groups in the United States, yet few studies have explored the spatiotemporal trend of the disease burden. To better understand mortality disparities by geographic regions over time, the present study analyzed the geographic variations of prostate cancer mortality by three Texas racial/ethnic groups over a 22-year period.

METHODS: The Spatial Scan Statistic developed by Kulldorff et al was used. Excess mortality was detected using scan windows of 50% and 90% of the study period and a spatial cluster size of 50% of the population at risk. Time trend was analyzed to examine …

Computer Simulation Of Glioma Growth And Morphology, Hermann B. Frieboes, John S Lowengrub, S Wise, X Zheng, Paul Macklin, Elaine L. Bearer, Vittorio Cristini

Faculty, Staff and Student Publications

Despite major advances in the study of glioma, the quantitative links between intra-tumor molecular/cellular properties, clinically observable properties such as morphology, and critical tumor behaviors such as growth and invasiveness remain unclear, hampering more effective coupling of tumor physical characteristics with implications for prognosis and therapy. Although molecular biology, histopathology, and radiological imaging are employed in this endeavor, studies are severely challenged by the multitude of different physical scales involved in tumor growth, i.e., from molecular nanoscale to cell microscale and finally to tissue centimeter scale. Consequently, it is often difficult to determine the underlying dynamics across dimensions. New techniques …

High-Resolution Vascular Imaging Of The Rat Spine Using Liposomal Blood Pool Mr Agent, K B Ghaghada, K H J Bockhorst, S Mukundan, A V Annapragada, P A Narayana

Faculty, Staff and Student Publications

BACKGROUND AND PURPOSE: High-resolution, vascular MR imaging of the spine region in small animals poses several challenges. The small anatomic features, extravascular diffusion, and low signal-to-noise ratio limit the use of conventional contrast agents. We hypothesize that a long-circulating, intravascular liposomal-encapsulated MR contrast agent (liposomal-Gd) would facilitate visualization of small anatomic features of the perispinal vasculature not visible with conventional contrast agent (gadolinium-diethylene-triaminepentaacetic acid [Gd-DTPA]). METHODS: In this study, high-resolution MR angiography of the spine region was performed in a rat model using a liposomal-Gd, which is known to remain within the blood pool for an extended period. The imaging …

Predictive Oncology: A Review Of Multidisciplinary, Multiscale In Silico Modeling Linking Phenotype, Morphology And Growth, Sandeep Sanga, Hermann B. Frieboes, Xiaoming Zheng, Robert Gatenby, Elaine L. Bearer, Vittorio Cristini

Faculty, Staff and Student Publications

Empirical evidence and theoretical studies suggest that the phenotype, i.e., cellular- and molecular-scale dynamics, including proliferation rate and adhesiveness due to microenvironmental factors and gene expression that govern tumor growth and invasiveness, also determine gross tumor-scale morphology. It has been difficult to quantify the relative effect of these links on disease progression and prognosis using conventional clinical and experimental methods and observables. As a result, successful individualized treatment of highly malignant and invasive cancers, such as glioblastoma, via surgical resection and chemotherapy cannot be offered and outcomes are generally poor. What is needed is a deterministic, quantifiable method to enable …

Towards A Hybrid Method To Categorize Interruptions And Activities In Healthcare, Juliana J. Brixey, David J. Robinson, Craig W. Johnson, Todd R. Johnson, James P. Turley, Vimla L. Patel, Jiajie Zhang

Faculty, Staff and Student Publications

ObjectiveInterruptions are known to have a negative impact on activity performance. Understanding how an interruption contributes to human error is limited because there is not a standard method for analyzing and classifying interruptions. Qualitative data are typically analyzed by either a deductive or an inductive method. Both methods have limitations. In this paper a hybrid method was developed that integrates deductive and inductive methods for the categorization of activities and interruptions recorded during an ethnographic study of physicians and registered nurses in a Level One Trauma Center. Understanding the effects of interruptions is important for designing and evaluating informatics …

Exploration Of Computational Methods For Classification Of Movement Intention During Human Voluntary Movement From Single Trial Eeg, Ou Bai, Peter Lin, Sherry Vorbach, Jiang Li, Steve Furlani, Mark Hallett

Electrical & Computer Engineering Faculty Publications

Objective: To explore effective combinations of computational methods for the prediction of movement intention preceding the production of self-paced right and left hand movements from single trial scalp electroencephalogram (EEG).

Methods: Twelve naïve subjects performed self-paced movements consisting of three key strokes with either hand. EEG was recorded from 128 channels. The exploration was performed offline on single trial EEG data. We proposed that a successful computational procedure for classification would consist of spatial filtering, temporal filtering, feature selection, and pattern classification. A systematic investigation was performed with combinations of spatial filtering using principal component analysis (PCA), independent component analysis …