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The Effect Of Salvage Therapy On Survival In A Longitudinal Study With Treatment By Indication, Edward Kennedy, Jeremy Taylor, Douglas Schaubel, Scott Williams 2009 University of Pennsylvania

The Effect Of Salvage Therapy On Survival In A Longitudinal Study With Treatment By Indication, Edward Kennedy, Jeremy Taylor, Douglas Schaubel, Scott Williams

Edward H. Kennedy

We consider using observational data to estimate the effect of a treatment on disease recurrence, when the decision to initiate treatment is based on longitudinal factors associated with the risk of recurrence. The effect of salvage androgen deprivation therapy (SADT) on the risk of recurrence of prostate cancer is inadequately described by the existing literature. Furthermore, standard Cox regression yields biased estimates of the effect of SADT, since it is necessary to adjust for prostate-specific antigen (PSA), which is a time-dependent confounder and an intermediate variable. In this paper, we describe and compare two methods which appropriately adjust for PSA ...


Using Database Marketing To Enhance Direct Marketing Alternatives In Jordanian Industrial Shareholders Corporations, Philadelphia University 2009 Philadelphia University

Using Database Marketing To Enhance Direct Marketing Alternatives In Jordanian Industrial Shareholders Corporations, Philadelphia University

Philadelphia University, Jordan

No abstract provided.


Corrosion And Passivation Of Tin In A Simulated Environment Has An Industrial Water, E. Ait Addi,, L. Bazzi, M. Mihit, R. Salghi 2009 Ibn-Zohr University

Corrosion And Passivation Of Tin In A Simulated Environment Has An Industrial Water, E. Ait Addi,, L. Bazzi, M. Mihit, R. Salghi

Mihit Mohammed Ph.D

No abstract provided.


An Oniom Study On The Enantioselective Diels-Alder Reaction Catalyzed By Sio 2 - Immobilized Chiral Oxazaborolidinium Cation, Sharifuddin Md Zain, Omar N. Y. M., Rahman N. A. 2009 University of Malaya

An Oniom Study On The Enantioselective Diels-Alder Reaction Catalyzed By Sio 2 - Immobilized Chiral Oxazaborolidinium Cation, Sharifuddin Md Zain, Omar N. Y. M., Rahman N. A.

Sharifuddin Md Zain

The mechanism and enantioselectivity of the Diels-Alder reaction between 2-methyl-1,3-butadiene and 2,3-dimethyl-1,4-benzoquinone catalyzed by SiO 2-supported chiral cationic oxazaborolidinium catalyst were investigated by the hybrid ONIOM(B3LYP/6-31G(d):UFF) method. The amorphous silica bulk was obtained by classical molecular dynamics using the melt-quench method and the heterogeneous surface was created by cleaving the bulk structure. The resultant amorphous silica surface was found to closely resemble silicas thermally treated at 673 K. The organocatalytic Diels-Alder reaction on the silica surface was observed to proceed via a concerted but highly asynchronous mechanism. The preferred transition state was found ...


The Novel And The Experimentation, Philadelphia University 2009 Philadelphia University

The Novel And The Experimentation, Philadelphia University

Philadelphia University, Jordan

No abstract provided.


A Substantial And Confusing Variation Exists In Handling Of Baseline Covariates In Randomized Controlled Trials: A Review Of Trials Published In Leading Medical Journals., Peter Austin 2009 Institute for Clinical Evaluative Sciences

A Substantial And Confusing Variation Exists In Handling Of Baseline Covariates In Randomized Controlled Trials: A Review Of Trials Published In Leading Medical Journals., Peter Austin

Peter Austin

Objective: Statisticians have criticized the use of significance testing to compare the distribution of baseline covariates between treatment groups in randomized controlled trials (RCTs). Furthermore, some have advocated for the use of regression adjustment to estimate the effect of treatment after adjusting for potential imbalances in prognostically important baseline covariates between treatment groups.

Study design and setting: We examined 114 RCTs published in the New England Journal of Medicine, the Journal of the American Medical Association, The Lancet, and the BMJ between January 1, 2007 and June 30, 2007.

Results: Significance testing was used to compare baseline characteristics between treatment ...


Bayesian Skew Selection For Multivariate Models, Michael Smith, Anastasios Panagiotelis 2009 Melbourne Business School

Bayesian Skew Selection For Multivariate Models, Michael Smith, Anastasios Panagiotelis

Michael Stanley Smith

We develop a Bayesian approach for the selection of skew in multivariate skew t distributions constructed through hidden conditioning in the manners suggested by either Azzalini and Capitanio (2003) or Sahu, Dey and Branco~(2003). We show that the skew coefficients for each margin are the same for the standardized versions of both distributions. We introduce binary indicators to denote whether there is symmetry, or skew, in each dimension. We adopt a proper beta prior on each non-zero skew coefficient, and derive the corresponding prior on the skew parameters. In both distributions we show that as the degrees of freedom ...


Statistical Simulation: Power Method Polynomials And Other Transformations, Todd Headrick 2009 Southern Illinois University Carbondale

Statistical Simulation: Power Method Polynomials And Other Transformations, Todd Headrick

Todd Christopher Headrick

Although power method polynomials based on the standard normal distributions have been used in many different contexts for the past 30 years, it was not until recently that the probability density function (pdf) and cumulative distribution function (cdf) were derived and made available. Focusing on both univariate and multivariate nonnormal data generation, Statistical Simulation: Power Method Polynomials and Other Transformations presents techniques for conducting a Monte Carlo simulation study. It shows how to use power method polynomials for simulating univariate and multivariate nonnormal distributions with specified cumulants and correlation matrices. The book first explores the methodology underlying the power method ...


Neural-Network-Based Fuzzy Identifier: Design And Evaluation, Philadelphia University 2009 Philadelphia University

Neural-Network-Based Fuzzy Identifier: Design And Evaluation, Philadelphia University

Philadelphia University, Jordan

No abstract provided.


Strong Ferromagnetic Metal-Ligand Exchange In A Nickel Bis(3,5-Dipyridylverdazyl) Complex, David Brook, Cardius Richardson, Benjamin Haller, Michael Hundley, Gordon Yee 2009 San Jose State University

Strong Ferromagnetic Metal-Ligand Exchange In A Nickel Bis(3,5-Dipyridylverdazyl) Complex, David Brook, Cardius Richardson, Benjamin Haller, Michael Hundley, Gordon Yee

David J. R. Brook

A new 1,5-dipyridyl verdazyl, synthesized from the corresponding dipyridyl hydrazone, coordinates nickel(II) to form a structurally characterized, pseudooctahedral complex analogous to Ni(terpy)22+. The unusually short Ni–verdazyl distance results in strong ferromagnetic exchange (JNi–rad = +300, Jrad–rad = +160 cm−1) between all three paramagnetic species along with a metal–ligand charge transfer band in the electronic spectrum.


On The Statistical Accuracy Of Biomarker Assays Of Hiv Incidence, Ron Brookmeyer 2009 University of California, Los Angeles

On The Statistical Accuracy Of Biomarker Assays Of Hiv Incidence, Ron Brookmeyer

Ron Brookmeyer

Objective: To evaluate the statistical accuracy of estimates of current HIV incidence rates from cross-sectional surveys, and to identify characteristics of assays that improve accuracy.

Methods: Performed mathematical and statistical analysis of the cross-sectional estimator of HIV incidence to evaluate bias and variance. Developed probability models to evaluate impact of long tails of the window period distribution on accuracy.

Results: The standard cross-sectional estimate of HIV incidence rate is estimating a time-lagged incidence where the lag time, called the shadow, depends on the mean and the coefficient of variation of window periods. Equations show how the shadow increases with the ...


Special Issue: Crop Water Use Efficiency At Multiple Scales, Timothy Green 2009 USDA Agricultural Research Service

Special Issue: Crop Water Use Efficiency At Multiple Scales, Timothy Green

Timothy R. Green

Food security is an issue of global concern, which is tightly linked with water supply issues as regional demands for water are dominated by agricultural water use. This special issue of Agricultural Water Management focuses on crop–water use in China, especially in the North China Plain (NCP) and Loess Plateau and surrounding areas, where intensive agriculture (e.g., wheat–maize double cropping) with limited water is practiced to meet the large demand for grains. Such intensive agriculture raises concerns for agricultural sustainability due to limited water supply and effects on water quality, which may be aggravated by projected climate ...


Regulation Of Patient Management Software, James Williams, Jens Weber 2009 University of Toronto

Regulation Of Patient Management Software, James Williams, Jens Weber

James B Williams

This paper addresses the use of medical device regimes to regulate electronic health record systems. Using Canada as our motivating example, we analyze whether a regulatory framework designed around hardware devices is suitable for use in the software domain. After presenting a thorough summary of the conceptual framework of medical device law, we consider the gaps and issues that arise when considering software systems. Our claim is that medical device regimes are not a suitable tool for the regulation of software, given the unique nature of software systems as engineering artifacts.


Testing Lyoequivalency For Three Commercially Sustainedrelease Tablets Containing Diltiazem Hydrochloride, Philadelphia University 2009 Philadelphia University

Testing Lyoequivalency For Three Commercially Sustainedrelease Tablets Containing Diltiazem Hydrochloride, Philadelphia University

Philadelphia University, Jordan

No abstract provided.


Characteristics Of Methyl Cellulose-Nh4no3-Peg Electrolyte And Application In Fuel Cells, Siti Rohana Majid, Shuhaimi N. E. A., Alias N. A., Kufian M. Z., Arof A. K. 2009 University of Malaya

Characteristics Of Methyl Cellulose-Nh4no3-Peg Electrolyte And Application In Fuel Cells, Siti Rohana Majid, Shuhaimi N. E. A., Alias N. A., Kufian M. Z., Arof A. K.

Siti Rohana Majid

We report the viability of methyl cellulose (MC) as a membrane in a polymer electrolyte membrane fuel cell (PEMFC). Methyl cellulose serves as the polymer host, ammonium nitrate (NH4NO3) as the doping salt and poly(ethylene glycol) (PEG) as plasticizer. Conductivity measurement was carried out using electrochemical impedance spectroscopy. The room temperature conductivity of pure MC film is is (3.08 +/- 0.63) x 10(-11)S cm(-1). The conductivity increased to (2.10 +/- 0.37) x 10(-6)S cm(-1) on addition of 25 wt.% NH4NO3. By adding 15 wt.% of PEG 200 to the highest conducting ...


Determination Of Chlorofluorocarbon Apparent Ages In Groundwater From The West Side Of The Island Of Hawaii, Jacque Kelly, Craig Glenn 2009 Georgia Southern University

Determination Of Chlorofluorocarbon Apparent Ages In Groundwater From The West Side Of The Island Of Hawaii, Jacque Kelly, Craig Glenn

Jacque L. Kelly

Large quantities of nutrient-enriched groundwater are supplied to coastal west Hawaii via point-sourced and diffuse groundwater seepage sites as submarine groundwater discharge. These inputs are especially important given that they are the only freshwater source to the coastal zone due to the absence of perennial streams. It has been suggested that discharging groundwaters are less than 50 years old; yet, the apparent ages of these groundwaters have not been investigated, despite the copious water volumes discharging to the coastal zone. Apparent age data is crucial to fully understand nutrient transformations along groundwater flow paths and will help constrain groundwater residence ...


The Evolution And Discovery Of The Species Of Equality In Euclid’S Elements, Lee Nutini 2009 The University of Tennessee College of Law

The Evolution And Discovery Of The Species Of Equality In Euclid’S Elements, Lee Nutini

Lee T Nutini

A look at the evidence for an additional and novel type of equality found in Euclid's Elements.


Dynamic Floating-Point Cancellation Detection (Master’S Degree Scholarly Paper), Michael Lam 2009 James Madison University

Dynamic Floating-Point Cancellation Detection (Master’S Degree Scholarly Paper), Michael Lam

Michael O Lam

No abstract provided.


Slope Stability Analysis Using Particle Swarm Optimization, Mohammad Khajehzadeh, Mohd Raihan Taha, Ahmed El-shafie 2009 Civil and Structural Engineering, National University of Malaysia

Slope Stability Analysis Using Particle Swarm Optimization, Mohammad Khajehzadeh, Mohd Raihan Taha, Ahmed El-Shafie

Mohammad Khajehzadeh

No abstract provided.


Reading, Reflecting, And Relating: A Metacognitive Approach To Learning, Karl Wirth, Fahima Aziz 2009 Macalester College

Reading, Reflecting, And Relating: A Metacognitive Approach To Learning, Karl Wirth, Fahima Aziz

Karl Wirth

No abstract provided.


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