Physical Sciences and Mathematics Commons^™

Earthquake Emergency Education In Dushanbe, Tajikistan, Rebecca Bendick

Rebecca Bendick

No abstract provided.

Improvement Of The Stoichiometric Network Analysis For Determination Of Instability Conditions Of Complex Nonlinear Reaction Systems, Zeljko D. Cupic

Zeljko D Cupic

No abstract provided.

Estimating Smooth Distribution Function In The Presence Of Heteroscedastic Measurement Errors, Xiao-Feng Wang, Zhaozhi Fan, Bin Wang

Xiaofeng Wang

Measurement error occurs in many biomedical fields. The challenges arise when errors are heteroscedastic since we literally have only one observation for each error distribution. This paper concerns the estimation of smooth distribution function when data are contaminated with heteroscedastic errors. We study two types of methods to recover the unknown distribution function: a Fourier-type deconvolution method and a simulation extrapolation (SIMEX) method. The asymptotics of the two estimators are explored and the asymptotic pointwise confidence bands of the SIMEX estimator are obtained. The finite sample performances of the two estimators are evaluated through a simulation study. Finally, we illustrate …

Ultrathin, Ultrasmooth And Low-Loss Silver Films Via Wetting And Annealing, Weiqiang Chen, Kuo-Ping Chen, Mark Daniel Thoreson, Alexander Kildishev, Vladimir M. Shalaev

Weiqiang Chen

We have demonstrated that a thermal annealing treatment can reduce the optical losses in ultrathin, ultrasmooth, silver films deposited on a Ge wetting layer to values as low as the bulk material value and at the same time maintain an ultrasmooth surface. The annealing effect is sensitive to the annealing temperature and time, both of which should be carefully controlled. This annealing treatment is also effective for Ag–SiO2 multilayer composite films.

Toward Superlensing With Metal-Dielectric Composites And Multilayers, Rasmus Bundgaard Nielsen, Mark Thoreson, Weiqiang Chen, Anders Kristensen, Jørn Hvam, Vladimir M. Shalaev, Alexandra Boltasseva

Weiqiang Chen

We report on the fabrication of two types of adjustable, near-field superlens designs: metal–dielectric composites and metal–dielectric multilayer films. We fabricated a variety of films with different materials, thicknesses and compositions. These samples were characterized physically and optically to determine their film composition, quality, and optical responses. Our results on metal–dielectric composites indicate that although the real part of the effective permittivity generally follows effective medium theory predictions, the imaginary part does not and substantially higher losses are observed. Going forward, it appears that multilayer metal–dielectric designs are more suitable for sub-diffraction imaging applications because they could provide both tunability …

Fabrication And Optical Characterizations Of Smooth Silver-Silica Nanocomposite Films, Weiqiang Chen, Mark Daniel Thoreson, Alexander V. Kildishev, Vladimir Shalaev

Weiqiang Chen

We have studied the surface-smoothing effect of an ultrathin germanium (Ge) layer on silver (Ag)-silica (SiO2) nanocomposite films for superlensing applications. Our experimental results indicate that inserting a thin Ge layer below the silver-silica composite films can reduce the final surface root-mean-squared (RMS) roughness to under 1 nm. Additionally, the metal nanostructure plays a role in both the smoothing effect and the optical properties of the nanocomposite films. Our experimental results show that the Bruggeman effective medium theory (EMT) is not sufficiently accurate to describe some properties of our nanocomposite films. In addition to the constituent materials and their filling …

Simulating Multivariate G-And-H Distributions, Rhonda K. Kowalchuk, Todd C. Headrick

Todd Christopher Headrick

The Tukey family of g-and-h distributions is often used to model univariate real-world data. There is a paucity of research demonstrating appropriate multivariate data generation using the g-and-h family of distributions with specified correlations. Therefore, the methodology and algorithms are presented to extend the g-and-h family from univariate to multivariate data generation. An example is provided along with a Monte Carlo simulation demonstrating the methodology. In addition, algorithms written in Mathematica 7.0 are available from the authors for implementing the procedure.

Statistical Simulation: Power Method Polynomials And Other Transformations, Todd C. 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, …

Sedimentary Setting Of Adriatic Flysch Formation (Middle Eocene-Middle Miocene), Southeastern Montenegro As Revealed By Turbidite Sequences., Zoran Kilibarda, Damjan Cadjenovic, Jelena Milutin, Novo Radulovic

Zoran Kilibarda

A 750 m long outcrop of Middle Eocene-Miocene flysch is exposed in an asymmetrical syncline in Crnjak Cove, south of Bar, Montenegro. Texture, physical sedimentary structures, petrography, and trace fossil studied in these sediments allowed the recognition of turbidite facies that display various members of the Bouma sequence (Ta,b,c,d,e). These are interpreted in order to reconstruct the depositional setting of these gravitational deposits. Predominantly clastic lihologies in this 300 m thick sequence are arranged in seven distinct turbidite facies, which represent three superimposed submarine fans. The oldest fan consists of: 1) basal marl (T1: 0-30 m), which indicate basin to …

Assessing The Impact Of Geosciences Laboratories On Student Learning: Who Benefits From Introductory Labs, Karl Nelson, Kristin Huysken, Zoran Kilibarda

Zoran Kilibarda

Laboratories serve as an integral part of geoscience education at most colleges and universities. While anecdotal evidence supports the beneficial impact of laboratories on science class learning, little quantitative research backs this statement. This study compared classroom data from students who completed a geoscience laboratory in conjunction with an introductory-level lecture-based course to those who completed the lecture course only. Laboratory-enrolled students performed better in the lecture class, resulting in an increase of 5.5% in their final class score. Even after controlling for GPA, laboratory enrollment accounted for a statistically significant proportion of the variance. Nontraditional students (age 25 and …

Identification Of Ovarian Cancer Symptoms In Health Insurance Claims Data., Paula Diehr, Sean Devlin

Paula Diehr

Background: Women with ovarian cancer have reported abdominal=pelvic pain, bloating, difficulty eating or feeling full quickly, and urinary frequency=urgency prior to diagnosis. We explored these findings in a general population using a dataset of insured women aged 40–64 and investigated the potential effectiveness of a routine review of claims data as a prescreen to identify women at high risk for ovarian cancer. Methods: Data from a large Washington State health insurer were merged with the Seattle-Puget Sound Surveillance, Epidemiology and End Results (SEER) cancer registry for 2000–2004. We estimated the prevalence of symptoms in the 36 months prior to diagnosis …

Removal Of Perchlorate (Clo4-) From Water Using Pulsed Arc Electrohydraulic Discharge (Paed), Sarah E. Dickson

Sarah E Dickson

No abstract provided.

Electrodeposition Of Quaternary Alloys In The Presence Of Magnetic Field, Yatimah Alias

Yatimah Alias

Electrodeposition of Ni-Co-Fe-Zn alloys was done in a chloride ion solution with the presence and absence of a Permanent Parallel Magnetic Field (PPMF). The PPMF was applied parallel to the cathode surface. The deposition profile was monitored chronoamperometrically. It was found that the electrodeposition current was enhanced in the presence of PPMF (9 T) compared to without PPMF. The percentage of current enhancement (Gamma%) was increased in the presence of PPMF, with results of Gamma% = 11.9%, 16.7% and 18.5% at -1.1, -1.2 and -1.3 V respectively for a 2400 sec duration. In chronoamperometry, the Composition Reference Line (CRL) for …

Multi-Component Bi-Layers Featuring 1-Octyl-2,3-Dimethylimidazolium Boolean And P-Sulfonatocalix 4 Arene Supermolecules, Yatimah Alias

Yatimah Alias

Multi-component solid state structures containing 1-octyl-2,3-dimethylimidazolium cations, anionic p-sulfonatocalix[4]arenes and/or large mono-phosphonium cations, as well as lanthanide metal ions are readily accessible, which have the calixarenes organised into bi-layers with gadolinium(III) coordinated between them. The imidazolium ring is confined in the calixarene cavity, essentially forming "molecular capsules'' based on two calixarenes, or with the n-octyl chain penetrating the adjacent bi-layer, with the nature of the calixarene-dimethylimidazolium interplay mapped out using Hirshfeld surface analysis. The supermolecules [1-octyl-2,3-dimethylimidazolium p-sulfonatocalix[4]arene] are persistent in aqueous solutions ((1)H NMR).

On Stern's Diatomic Sequence 0,1,1,2,1,3,2,3,1,3,4,..., Sam Northshield

Sam Northshield

Stern’s diatomic sequence is a simply defined sequence with an amazing set of properties. Our goal is to present many of these properties—those that have most impressed the author.

My Curriculum Vitae (As January 2013), Yun Hau Ng

Yun Hau Ng

References available upon request

The Coconut Palm, Cocos Nucifera, Impacts Forest Composition And Soil Characteristics At Palmyra Atoll, Central Pacific, Hillary S. Young, Ted K. Raab, Douglas J. Mccauley, Amy A. Briggs, Rodolfo Dirzo

Ted K. Raab

Cocos nucifera, the coconut palm, has a pantropical distribution and reaches near monodominance in many atolls, low lying islands and coastal regions. This paper examines the ecological correlation between C. nucifera abundance and changes in forest structure, floristic diversity and forest soil characteristics. Cumulatively, these data show that C. nucifera has important impacts on floristic, structural and soil characteristics of forests where it becomes dominant. Given the high proportion of tropical coastal areas in which C. nucifera is now naturalized and abundant, this likely has important implications for coastal forest diversity and structure.

The Rhizosphere: A Synchrotron- Based View Of Nutrient Flow In The Root Zone, Theodore K. Raab, David A. Lipson

Ted K. Raab

At two energy “endpoints” of the EM spectrum accessible to synchrotron biologists (IR radiation and soft X-rays), we have found experimental methods providing unique opportunities to observe processes and test hypotheses essential to understanding plantsoil- microbe interactions. Availability of IR synchrotron beamlines will continue to expand worldwide, and we hope that plant and microbial biologists will incorporate the type of spectral data presented in this chapter as just one of a legion of “-omics” methods. Considering the shear flux of C through belowground ecosystems annually (and how poorly constrained they are in many regions), synchrotrons must continue to demand the …

(2e)-1-(6-Chloro-2-Methyl-4-Phenylquinolin-3-Yl)-3-Phenylprop-2-En-1-One, Tan Kong Wai, Viji A. J., Vijayakumar V., Sarveswari S.

Tan Kong Wai

In the title compound, C(25)H(18)ClNO, the conformation about the C=C double bond is E. Significant twists are evident in the molecule, with the benzene ring forming a dihedral angle of 53.92 (11)degrees with the quinolinyl residue. Further, the chalcone residue is approximately perpendicular to the quinolinyl residue [C(q)-C(q)-C(c)-O(c) torsion angle = -104.5 (3)degrees, where q = quinolinyl and c = chalcone]. In the crystal, the presence of C-H center dot center dot center dot O and C-H center dot center dot center dot pi interactions leads to supramolecular layers lying parallel to ((1) over bar 02).

Targeted Maximum Likelihood Estimation Of The Parameter Of A Marginal Structural Model, Michael Rosenblum, Mark J. Van Der Laan

Michael Rosenblum

Targeted maximum likelihood estimation is a versatile tool for estimating parameters in semiparametric and nonparametric models. We work through an example applying targeted maximum likelihood methodology to estimate the parameter of a marginal structural model. In the case we consider, we show how this can be easily done by clever use of standard statistical software. We point out differences between targeted maximum likelihood estimation and other approaches (including estimating function based methods). The application we consider is to estimate the effect of adherence to antiretroviral medications on virologic failure in HIV positive individuals.

Shoulder Surfing Resistance Using Penup Event And Neighbouring Connectivity Manipulation, Miss Laiha Mat Kiah

Miss Laiha Mat Kiah

Picture-based password has been proposed as an alternative authentication method to replace text-based password. Ensuring the security of picture-based password is not a simple task as picture-based objects are a lot easier to access and remember and can thus be easily guessed. In particular, shoulder surfing attack still remains as the main security threat encountered by many picture-based password authentication schemes, especially in drawmetric authentication scheme. In this paper, a novel shoulder surfing resistance mechanism has been proposed and evaluated. The proposed mechanism utilises penup event and neighbouring connectivity manipulation into a revised Background Pass-Go scheme. From the evaluation result, …

Mitigation And The Geoengineering Threat, Juan B. Moreno-Cruz

Juan B. Moreno-Cruz

Recent scientific advances have introduced the possibility of engineering the climate system to lower ambient temperatures without lowering greenhouse gas concentrations. This possibility has created an intense debate given the ethical, moral and scientific questions it raises. In this paper I examine the economic issues introduced when geoengineering becomes available in a standard two-period two-country model where strategic interaction leads to suboptimal mitigation. Geoengineering introduces the possibility of technical substitution away from mitigation, but it also affects the strategic interaction across countries: mitigation decisions made in the first period directly affect the geoengineering decisions made in the second period. With …

Revisiting The Economics Of Climate Change: The Role Of Geoengineering, Juan B. Moreno-Cruz, Sjak Smulders

Juan B. Moreno-Cruz

Technically simple and reversible measures to directly reduce mean global temper- atures could be available anytime soon. We introduce the concept of \geoengineering" into an analytical model of climate change. We model the technical and economic characteristics of geoengineering in line with the recent literature from physical and environmental management sciences. We investigate (i) under which circumstances geoengineering can substitute, partly or completely, for traditional abatement strate- gies, (ii) under which conditions and at what level geoengineering is optimally em- ployed, and (iii) whether geoengineering can mitigate free-riding problems.

Mth 101/Fse 013 Tutorial, Morufu Oyedunsi Olayiwola

OLAYIWOLA Morufu Oyedunsi

No abstract provided.

Meta-Analysis Of Fertilization Experiments Indicates Multiple Limiting Nutrients In Northeastern Deciduous Forests, Matthew A. Vadeboncoeur

Matthew A Vadeboncoeur

It is widely accepted that N limits primary production in temperate forests, although colimitation by N and P has also been suggested, and on some soils, Ca and base cations are in short supply. I conducted a meta-analysis to assess the strength of existing experimental evidence for limitation of primary production by N, P, and Ca in hardwood forests of the northeastern United States and southeastern Canada using data from 35 fertilization experiments in deciduous forests on glaciated soils across the region.

There is strong evidence for N limitation (formal meta-analysis weighted mean response ratio = 1.51, p < 0.01; simple mean = 1.42, p < 0.001). Forest productivity also tended to increase with additions of P (simple mean = 1.15, p = 0.05) and Ca (simple mean = 1.36, p < 0.001). Across all treatments, 85% of response ratios were positive. Multiple-element additions had larger effects than single elements, but factorial experiments showed little evidence of synergistic effects between nutrient additions. Production responses correlated positively with the rate of N fertilization, but this effect was reduced at high rates of ambient N deposition.

Application Of Causal Inference Methods To Improve The Treatment Of Hiv In Resource-Limited Settings., Maya Petersen

Maya Petersen

No abstract provided.

Simple Room-Temperature Preparation Of High-Yield Large-Area Graphene Oxide, Huang Nay Ming

Huang Nay Ming

Graphene has attracted much attention from researchers due to its interesting mechanical, electrochemical, and electronic properties. It has many potential applications such as polymer filler, sensor, energy conversion, and energy storage devices. Graphene-based nanocomposites are under an intense spotlight amongst researchers. A large amount of graphene is required for preparation of such samples. Lately, graphene-based materials have been the target for fundamental life science investigations. Despite graphene being a much sought-after raw material, the drawbacks in the preparation of graphene are that it is a challenge amongst researchers to produce this material in a scalable quantity and that there is …

Observations Of Ozone Production In A Dissipating Tropical Convective Cell During Tc4, Gary A. Morris, A. M. Thompson, K. E. Pickering, S. Chen, E. J. Bucsela, P. A. Kucera

Gary A. Morris

From 13 July–9 August 2007, 25 ozonesondes were launched from Las Tablas, Panama as part of the Tropical Composition, Cloud, and Climate Coupling (TC4) mission. On 5 August, a strong convective cell formed in the Gulf of Panama. World Wide Lightning Location Network (WWLLN) data indicated 563 flashes (09:00–17:00 UTC) in the Gulf. NO2 data from the Ozone Monitoring Instrument (OMI) show enhancements, suggesting lightning production of NOx. At 15:05 UTC, an ozonesonde ascended into the southern edge of the now dissipating convective cell as it moved west across the Azuero Peninsula. The balloon oscillated from 2.5–5.1 km five times …

2-(3-Nitrophenoxy)Quinoxaline, Hairul Anuar Bin Tajuddin

Hairul Anuar Bin Tajuddin

In the title molecule, C(14)H(9)N(3)O(3), the dihedral angle between the quinoxaline and benzene rings is 77.13 (9)degrees. The molecule is twisted about the ether-benzene O-C bond, with a C-O-C-C torsion angle of -102.8 (2)degrees. In the crystal, molecules are linked by C-H center dot center dot center dot O hydrogen bonds, forming layers in the ab plane, with one nitro O atom accepting two such interactions. The layers stack along the c-axis direction via weak C-H center dot center dot center dot pi interactions.

Sphet: Spatial Models With Heteroskedastic Innovations In R, Gianfranco Piras

Gianfranco Piras

No abstract provided.