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Full-Text Articles in Medicine and Health Sciences

Building New Culture Media For Assisted Reproductive Technology., Mary N. Egbuniwe, H. Lee Higdon Iii, William R. Boone Jan 2004

Building New Culture Media For Assisted Reproductive Technology., Mary N. Egbuniwe, H. Lee Higdon Iii, William R. Boone

Journal of the South Carolina Academy of Science

No abstract provided.


Reconstructability Analysis: Theory And Applications [Editorial Introduction], Martin Zwick, Guangfu Shu, Yi Lin Jan 2004

Reconstructability Analysis: Theory And Applications [Editorial Introduction], Martin Zwick, Guangfu Shu, Yi Lin

Complex Systems Faculty Publications and Presentations

Reconstructability analysis (RA) dates back to the pioneering work of Ashby in the mid-1960s. In the 1970s and 1980s, RA was the subject of very active research in the systems community. It receded for a time as a focus of activity, but the special issue of the International Journal of General Systems in 1996 on the General Systems Problem Solver and the special IJGS issue in 2000 on Reconstructability Analysis in China marked the renewal of interest in this area. The current volume is part of this resurgence of activity. It collects together papers from the group at Portland State …


Advances And Applications Of Dezert-Smarandache Theory (Dsmt), Vol. 1, Florentin Smarandache, Jean Dezert Jan 2004

Advances And Applications Of Dezert-Smarandache Theory (Dsmt), Vol. 1, Florentin Smarandache, Jean Dezert

Branch Mathematics and Statistics Faculty and Staff Publications

The Dezert-Smarandache Theory (DSmT) of plausible and paradoxical reasoning is a natural extension of the classical Dempster-Shafer Theory (DST) but includes fundamental differences with the DST. DSmT allows to formally combine any types of independent sources of information represented in term of belief functions, but is mainly focused on the fusion of uncertain, highly conflicting and imprecise quantitative or qualitative sources of evidence. DSmT is able to solve complex, static or dynamic fusion problems beyond the limits of the DST framework, especially when conflicts between sources become large and when the refinement of the frame of the problem under consideration …


Phytoplankton Composition Within The Tidal Freshwater-Oligohaline Regions Of The Rappahannock And Pamunkey Rivers In Virginia, Harold G. Marshall, Lubomira Burchardt Jan 2004

Phytoplankton Composition Within The Tidal Freshwater-Oligohaline Regions Of The Rappahannock And Pamunkey Rivers In Virginia, Harold G. Marshall, Lubomira Burchardt

Biological Sciences Faculty Publications

The Rappahannock River is a major river system across north central Virginia prior to entering the Chesapeake Bay. In contrast, the Pamunkey River is smaller in size and joins the Mattoponi River to form the York River, which flows parallel to the Rappahannock before it also flows into Chesapeake Bay. A unique mixing area for both flora and environmental conditions exists in the tidal freshwater-oligohaline region of both rivers. This is a dynamic mixing section where freshwater and estuarine species are subject to the interaction of river flow and daily tidal rhythms. The phytoplankton composition in this region of the …


Evaluating The Disparity Of Female Breast Cancer Mortality Among Racial Groups - A Spatiotemporal Analysis, Chiehwen E. Hsu, Holly Jacobson, Francisco Soto Mas Jan 2004

Evaluating The Disparity Of Female Breast Cancer Mortality Among Racial Groups - A Spatiotemporal Analysis, Chiehwen E. Hsu, Holly Jacobson, Francisco Soto Mas

Faculty, Staff and Student Publications

Background The literature suggests that the distribution of female breast cancer mortality demonstrates spatial concentration. There remains a lack of studies on how the mortality burden may impact racial groups across space and over time. The present study evaluated the geographic variations in breast cancer mortality in Texas females according to three predominant racial groups (non-Hispanic White, Black, and Hispanic females) over a twelve-year period. It sought to clarify whether the spatiotemporal trend might place an uneven burden on particular racial groups, and whether the excess trend has persisted into the current decade.

Methods The Spatial Scan Statistic was employed …


Development Of Dose Coefficients For Radionuclides Produced In Spallation Targets, Phillip W. Patton, Mark Rudin Jan 2004

Development Of Dose Coefficients For Radionuclides Produced In Spallation Targets, Phillip W. Patton, Mark Rudin

Transmutation Sciences Physics (TRP)

Dose coefficients permit simple determination of radiation dose associated with various exposure scenarios, and ultimately permit radiation safety personnel to assess the health risks to workers in a nuclear facility. Specifically, radiation safety personnel use dose coefficients to determine the radiation dose incurred to a tissue or organ system from a given exposure. These parameters are often expressed in terms of Annual Limits on Intake (ALIs) and Derived Air Concentrations (DACs).

Results from this study will be used to produce ALIs and DACs for these rare radionuclides created by spallation target systems that are not included in Federal Guidance Report …


Detecting Spatiotemporal Clusters Of Accidental Poisoning Mortality Among Texas Counties, Us, 1980 – 2001, Ella T. Nkhoma, Chiehwen E. Hsu, Victoria I. Hunt, Ann M. Harris Jan 2004

Detecting Spatiotemporal Clusters Of Accidental Poisoning Mortality Among Texas Counties, Us, 1980 – 2001, Ella T. Nkhoma, Chiehwen E. Hsu, Victoria I. Hunt, Ann M. Harris

Faculty, Staff and Student Publications

Background Accidental poisoning is one of the leading causes of injury in the United States, second only to motor vehicle accidents. According to the Centers for Disease Control and Prevention, the rates of accidental poisoning mortality have been increasing in the past fourteen years nationally. In Texas, mortality rates from accidental poisoning have mirrored national trends, increasing linearly from 1981 to 2001. The purpose of this study was to determine if there are spatiotemporal clusters of accidental poisoning mortality among Texas counties, and if so, whether there are variations in clustering and risk according to gender and race/ethnicity. The Spatial …


Response Of Dark-Adapted Retinal Rod Photoreceptors, H. Khanal, V. Alexiades, E. Dibenedetto Jan 2004

Response Of Dark-Adapted Retinal Rod Photoreceptors, H. Khanal, V. Alexiades, E. Dibenedetto

Publications

The process of phototransduction, whereby light is converted into an electrical response, in rod and cone photoreceptors in the retina, involves as a key setp, the diffusion of the cytoplasmic, signaling molecules cGMP (cyclic guanosime monophosphate) and Ca2+ diffuse in the cytoplasm (the fluid surrounding the discs). the complex geometry of the rod creates computational difficulties. We present spatio-temporal compuational models for interacctions and diffusion of cGMP and Ca2+ in the cytoplasm of vertebrate rod photoreceptors, as well as numerical simulations fo the response to light of dark-adapted Salamander rods.


Uncertainty And The Value Of Diagnostic Information With Application To Axillary Lymph Node Dissection In Breast Cancer, Giovanni Parmigiani Dec 2003

Uncertainty And The Value Of Diagnostic Information With Application To Axillary Lymph Node Dissection In Breast Cancer, Giovanni Parmigiani

Johns Hopkins University, Dept. of Biostatistics Working Papers

In clinical decision making, it is common to ask whether, and how much, a diagnostic procedure is contributing to subsequent treatment decisions. Statistically, quantification of the value of the information provided by a diagnostic procedure can be carried out using decision trees with multiple decision points, representing both the diagnostic test and the subsequent treatments that may depend on the test's results. This article investigates probabilistic sensitivity analysis approaches for exploring and communicating parameter uncertainty in such decision trees. Complexities arise because uncertainty about a model's inputs determines uncertainty about optimal decisions at all decision nodes of a tree. We …


Survival Model Predictive Accuracy And Roc Curves, Patrick Heagerty, Yingye Zheng Dec 2003

Survival Model Predictive Accuracy And Roc Curves, Patrick Heagerty, Yingye Zheng

UW Biostatistics Working Paper Series

The predictive accuracy of a survival model can be summarized using extensions of the proportion of variation explained by the model, or R^2, commonly used for continuous response models, or using extensions of sensitivity and specificity which are commonly used for binary response models.

In this manuscript we propose new time-dependent accuracy summaries based on time-specific versions of sensitivity and specificity calculated over risk sets. We connect the accuracy summaries to a previously proposed global concordance measure which is a variant of Kendall's tau. In addition, we show how standard Cox regression output can be used to obtain estimates of …


Semiparametric Estimation Of Time-Dependent: Roc Curves For Longitudinal Marker Data, Yingye Zheng, Patrick Heagerty Dec 2003

Semiparametric Estimation Of Time-Dependent: Roc Curves For Longitudinal Marker Data, Yingye Zheng, Patrick Heagerty

UW Biostatistics Working Paper Series

One approach to evaluating the strength of association between a longitudinal marker process and a key clinical event time is through predictive regression methods such as a time-dependent covariate hazard model. For example, a time-varying covariate Cox model specifies the instantaneous risk of the event as a function of the time-varying marker and additional covariates. In this manuscript we explore a second complementary approach which characterizes the distribution of the marker as a function of both the measurement time and the ultimate event time. Our goal is to flexibly extend the standard diagnostic accuracy concepts of sensitivity and specificity to …


Optimization Of Breast Cancer Screening Modalities, Yu Shen, Giovanni Parmigiani Dec 2003

Optimization Of Breast Cancer Screening Modalities, Yu Shen, Giovanni Parmigiani

Johns Hopkins University, Dept. of Biostatistics Working Papers

Mathematical models and decision analyses based on microsimulations have been shown to be useful in evaluating relative merits of various screening strategies in terms of cost and mortality reduction. Most investigations regarding the balance between mortality reduction and costs have focused on a single modality, mammography. A systematic evaluation of the relative expenses and projected benefit of combining clinical breast examination and mammography is not at present available. The purpose of this report is to provide methodologic details including assumptions and data used in the process of modeling for complex decision analyses, when searching for optimal breast cancer screening strategies …


Modeling The Incubation Period Of Anthrax, Ron Brookmeyer, Elizabeth Johnson, Sarah Barry Dec 2003

Modeling The Incubation Period Of Anthrax, Ron Brookmeyer, Elizabeth Johnson, Sarah Barry

Johns Hopkins University, Dept. of Biostatistics Working Papers

Models of the incubation period of anthrax are important to public health planners because they can be used to predict the delay before outbreaks are detected, the size of an outbreak and the duration of time that persons should remain on antibiotics to prevent disease. The difficulty is that there is little direct data about the incubation period in humans. The objective of this paper is to develop and apply models for the incubation period of anthrax. Mechanistic models that account for the biology of spore clearance and germination are developed based on a competing risks formulation. The models predict …


Acknowledgements, The Mcnair Team Dec 2003

Acknowledgements, The Mcnair Team

McNair Scholars Research Journal

No abstract provided.


Notes From The Director, The Mcnair Team Dec 2003

Notes From The Director, The Mcnair Team

McNair Scholars Research Journal

No abstract provided.


Mcnair Scholars Program, The Mcnair Team Dec 2003

Mcnair Scholars Program, The Mcnair Team

McNair Scholars Research Journal

No abstract provided.


Message From The Provost, The Mcnair Team Dec 2003

Message From The Provost, The Mcnair Team

McNair Scholars Research Journal

No abstract provided.


Full Issue, The Mcnair Team Dec 2003

Full Issue, The Mcnair Team

McNair Scholars Research Journal

No abstract provided.


Clinical Effectiveness Of A Subperiosteal Anchorage Device, Monica Anne Witte Dec 2003

Clinical Effectiveness Of A Subperiosteal Anchorage Device, Monica Anne Witte

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this pilot study was to evaluate the clinical efficacy of a subperiosteal anchorage device, the palatal OnPlant™, during orthodontic retraction of protruding anterior teeth in cases requiring maxillary premolar extraction. Seven subjects (5 female, 2 male), ages 13 to 55, were selected for the study. The OnPlant was surgically placed in the mid-palatal region through a well-defined subperiosteal tunnel. Following the manufacturer recommended osseointegration period of four months, the OnPlant was uncovered and attached to the first molars by means of a transpalatal bar. Standard orthodontic treatment then commenced to retract the anterior teeth after the first …


Comparison Of Bracket Bond Strength By Total, Self-Etch And Laser Treatment, Kyo Sung Shawn Kim Dec 2003

Comparison Of Bracket Bond Strength By Total, Self-Etch And Laser Treatment, Kyo Sung Shawn Kim

Loma Linda University Electronic Theses, Dissertations & Projects

Laser etching of enamel surfaces alters the physical and chemical characteristics of the enamel. These changes in characteristics enhance the bonding to enamel. The purpose of this study was to compare the shear and tensile bond strength of Er,Cr:YSGG hydrokinetic laser system (Biolase) with 37% phosphoric acid and self etching primer 30 minutes and 72 hours after bonding. Four different laser power output setting was observed: 1.5W, 2.0W, 2.5W, and 3.0W. Two hundred forty bovine teeth free of defect, caries, and dentin exposure were mounted in acrylic resin and divided into 24 groups of 10 teeth. Sixteen groups of 10 …


A Bond Strength Comparison Of Led And Halogen Light Curing Units, John Richard Kavanagh Dec 2003

A Bond Strength Comparison Of Led And Halogen Light Curing Units, John Richard Kavanagh

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this research was to compare the tensile bond strength of orthodontic flat based buttons bonded to bovine teeth with four commercial light-emitting diode (LED) curing lights and one conventional quartz tungsten halogen (QTH) curing light.

The dental market has recently been introduced to a number of commercially available light-emitting diode (LED) curing lights. Tensile bond strength was evaluated for LED curing lights (Rembrandt® AllegroTM, Den-Mat Corp, Santa Maria, CA), (LEDemetron, Kerr/Demetron Corp, Danbury, Conn), (Ortholux LED, 3MTMESPETM, St. Paul, MN),and (FLASH-lite 1001, Discus Dental, Culver City, CA) are compared with one …


Data Analysis In The Antes System, Yavuz Tor Dec 2003

Data Analysis In The Antes System, Yavuz Tor

Theses and Dissertations - UTB/UTPA

Acanthosis nigricans is a skin condition that can be used as an indicator for the risk of developing type 2 diabetes in the future. Border Health Office, in University of Texas - Pan American, organizes screenings in schools for acanthosis nigricans. Screening results are, then, collected and evaluated in the Border Health Office. The ANTES System is a computer system that stores and manages the data collected in those screenings.

This study is on the analysis of those collected data to track the progress of data entry, to evaluate the progress on obesity and related problems, and to discover the …


Antes: A Web-Based Acanthosis Nigricans And Other Obesity Related Information System, Chunyue Wang Dec 2003

Antes: A Web-Based Acanthosis Nigricans And Other Obesity Related Information System, Chunyue Wang

Theses and Dissertations - UTB/UTPA

Acanthosis nigricans is a cutaneous marker associated with systemic disorders and may serve as an indicator for risk of Type 2 diabetes. Acanthosis nigricans screening can help identify children who have high insulin levels and who may be at-risk for developing Type 2 diabetes. The ANTES system is a computerization attempt for acanthosis nigricans control of the student population from elementary schools and secondary schools in Texas. A general description of the system and the medical and history background of the ANTES program is given. The technology applied to the system is demonstrated. An overview of the system operation status …


Development Of Dose Conversion Coefficients For Radionuclides Produced In Spallation Neutron Sources: Quarterly Progress Report 8/20/03 – 12/01/03, Phillip W. Patton, Mark Rudin Dec 2003

Development Of Dose Conversion Coefficients For Radionuclides Produced In Spallation Neutron Sources: Quarterly Progress Report 8/20/03 – 12/01/03, Phillip W. Patton, Mark Rudin

Transmutation Sciences Physics (TRP)

A research consortium comprised of representatives from several universities and national laboratories has been established as part of this project to generate internal and external dose conversion coefficients for radionuclides produced in spallation neutron sources. Information obtained from this multi-year study will be used to support the siting and licensing of future accelerator-driven nuclear initiatives within the U.S. Department of Energy complex, including the Spallation Neutron Source (SNS) and Accelerator Production of Tritium (APT) Projects. Determination of these coefficients will also fill data gaps for several hundred radionuclides that exist in Federal Guide Report No. 11 and in Publications 68 …


Time-Series Studies Of Particulate Matter, Michelle L. Bell, Jonathan M. Samet, Francesca Dominici Nov 2003

Time-Series Studies Of Particulate Matter, Michelle L. Bell, Jonathan M. Samet, Francesca Dominici

Johns Hopkins University, Dept. of Biostatistics Working Papers

Studies of air pollution and human health have evolved from descriptive studies of the early phenomena of large increases in adverse health effects following extreme air pollution episodes, to time-series analyses and the development of sophisticated regression models. In fact, advanced statistical methods are necessary to address the many challenges inherent in the detection of a small pollution risk in the presence of many confounders. This paper reviews the history, methods, and findings of the time-series studies estimating health risks associated with short-term exposure to particulate matter, though much of the discussion is applicable to epidemiological studies of air pollution …


Smooth Quantile Ratio Estimation With Regression: Estimating Medical Expenditures For Smoking Attributable Diseases, Francesca Dominici, Scott L. Zeger Nov 2003

Smooth Quantile Ratio Estimation With Regression: Estimating Medical Expenditures For Smoking Attributable Diseases, Francesca Dominici, Scott L. Zeger

Johns Hopkins University, Dept. of Biostatistics Working Papers

In this paper we introduce a semi-parametric regression model for estimating the difference in the expected value of two positive and highly skewed random variables as a function of covariates. Our method extends Smooth Quantile Ratio Estimation (SQUARE), a novel estimator of the mean difference of two positive random variables, to a regression model.

The methodological development of this paper is motivated by a common problem in econometrics where we are interested in estimating the difference in the average expenditures between two populations, say with and without a disease, taking covariates into account. Let Y1 and Y2 be two positive …


A Corrected Pseudo-Score Approach For Additive Hazards Model With Longitudinal Covariates Measured With Error, Xiao Song, Yijian Huang Nov 2003

A Corrected Pseudo-Score Approach For Additive Hazards Model With Longitudinal Covariates Measured With Error, Xiao Song, Yijian Huang

UW Biostatistics Working Paper Series

In medical studies, it is often of interest to characterize the relationship between a time-to-event and covariates, not only time-independent but also time-dependent. Time-dependent covariates are generally measured intermittently and with error. Recent interests focus on the proportional hazards framework, with longitudinal data jointly modeled through a mixed effects model. However, approaches under this framework depend on the normality assumption of the error, and might encounter intractable numerical difficulties in practice. This motivates us to consider an alternative framework, that is, the additive hazards model, under which little has been done when time-dependent covariates are measured with error. We propose …


Smooth Quantile Ratio Estimation, Francesca Dominici, Leslie Cope, Daniel Q. Naiman, Scott L. Zeger Oct 2003

Smooth Quantile Ratio Estimation, Francesca Dominici, Leslie Cope, Daniel Q. Naiman, Scott L. Zeger

Johns Hopkins University, Dept. of Biostatistics Working Papers

In a study of health care expenditures attributable to smoking, we seek to compare the distribution of medical costs for persons with lung cancer or chronic obstructive pulmonary disease (cases) to those without (controls) using a national survey which includes hundreds of cases and thousands of controls. The distribution of costs is highly skewed toward larger values, making estimates of the mean from the smaller sample dependent on a small fraction of the biggest values. One approach to deal with the smaller sample is to rely on a simple parametric model such as the log-normal, but this makes the undesirable …


Ua66/1/5 Applied Research & Technology Program Newsletter, Issue 2, Wku Applied Research & Technology Program Oct 2003

Ua66/1/5 Applied Research & Technology Program Newsletter, Issue 2, Wku Applied Research & Technology Program

WKU Administration Documents

Newsletter created by and about the Applied Research & Technology Program.


Santa Clara Magazine, Volume 45 Number 2, Fall 2003, Santa Clara University Oct 2003

Santa Clara Magazine, Volume 45 Number 2, Fall 2003, Santa Clara University

Santa Clara Magazine

12 - 'A FAVORITE ABODE OF SCIENCE' By Elizabeth Kelley Gillogly '93. A new exhibit of Santa Clara University's scientific equipment from 1851-1900 reveals the Jesuits' early dedication to scientific inquiry, and the ways in which the University contributed to the history of science.

14 - COMING HOME By Mitch Finley '73. More than 60 million Americans are Catholic, but millions of them are estranged from the Church. More often than you might think, however, "lapsed Catholics" decide to come home to the Church. Why did they leave? And what brings them back?

18 - STUDENTS TO THE RESCUE By …