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Articles 1231 - 1260 of 2524

Full-Text Articles in Physical Sciences and Mathematics

On The Road To Intelligent Web Applications, Hisham Assal, Kym Pohl, Jens Pohl Feb 2013

On The Road To Intelligent Web Applications, Hisham Assal, Kym Pohl, Jens Pohl

Hisham Assal

Increasing access to data sources on the Internet offers expanding opportunities for equipping intelligent applications with the content they require whether broad in scope or rich in detail. Although typically originating within the web in a semi-structured form, with the use of inference-based translation and analysis mechanisms such content can be transformed into useful information and ultimately into actionable knowledge. Service-Oriented Architecture (SOA) offers a platform for accessing the web as invocable resources and effectively incorporating multiple sources of data and capabilities on the Internet into enterprise applications. Adding inference capabilities to SOA-based applications not only aids in the translation …

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Free-Standing Single-Walled Carbon Nanotube/Sno2 Anode Paper For Flexible Lithium-Ion Batteries, Lukman Noerochim, Jia-Zhao Wang, Shulei Chou, David Wexler Feb 2013

Free-Standing Single-Walled Carbon Nanotube/Sno2 Anode Paper For Flexible Lithium-Ion Batteries, Lukman Noerochim, Jia-Zhao Wang, Shulei Chou, David Wexler

Shulei Chou

Free-standingsingle-walledcarbonnanotube/SnO2 (SWCNT/SnO2) anodepaper was prepared by vacuum filtration of SWCNT/SnO2 hybrid material which was synthesized by the polyol method. From field emission scanning electron microscopy and transmission electron microscopy, the CNTs form a three-dimensional nanoporous network, in which ultra-fine SnO2 nanoparticles, which had crystallite sizes of less than 5 nm, were distributed, predominately as groups of nanoparticles on the surfaces of singlewalled CNT bundles. Electrochemical measurements demonstrated that the anodepaper with 34 wt.% SnO2 had excellent cyclic retention, with the high specific capacity of 454 mAh g−1 beyond 100 cycles at a current …

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Irradiation Si On Carbon Nanotube Paper As A Flexible Anode Material For Lithium-Ion Batteries, Shulei Chou, Mihail Ionescu, Jia-Zhao Wang, Brad Winton, Hua Liu Feb 2013

Irradiation Si On Carbon Nanotube Paper As A Flexible Anode Material For Lithium-Ion Batteries, Shulei Chou, Mihail Ionescu, Jia-Zhao Wang, Brad Winton, Hua Liu

Shulei Chou

Silicon single walled carbon nanotube composite paper was modified by low energy ion implantation using 5i to obtain a flexible composite paper. Raman and FE-SEM results show that structure of SWCNT could be destroyed by the implantation. Electrochemical measurements display that the implanted SI can improve the specific capacity and the reversible capacity of CNT paper. After 50 cycles, the specific capacity of 5Hmplanted CNT paper is 30 per cent higher than the pristine CNT.

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Activating The Teaching-Research Nexus In Smaller Universities: Case Studies Highlighting Diversity Of Practice, William Boyd, Meg O'Reilly, Daniel Bucher, Kath Fisher, Anja Morton, Peter Harrison, Elaine Nuske, Rebecca Coyle, Karyn Rendall Feb 2013

Activating The Teaching-Research Nexus In Smaller Universities: Case Studies Highlighting Diversity Of Practice, William Boyd, Meg O'Reilly, Daniel Bucher, Kath Fisher, Anja Morton, Peter Harrison, Elaine Nuske, Rebecca Coyle, Karyn Rendall

Dr Meg O'Reilly

The teaching-research nexus (TRN) has become an important process in the modern University, providing both identity to university scholarship and a device for the integration of academics’ work. Over the last decade many reports have identified the need to both establish institution-wide processes to embed and support TRN, and assist in academic professional development in adopting TRN. This case study reports one such institutional project, focussing on one element of the staff development program, a TRN panel discussion by academics who have engaged TRN. The discussion was structured around the five TRN dimensions of: Learning through research; Research-led teaching; Researching …

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The European Court Of Human Rights Ruling Against Britain's Policy Of Keeping Fingerprints & Dna Samples Of Criminal Suspects, K. Michael, Clive Harfield Feb 2013

The European Court Of Human Rights Ruling Against Britain's Policy Of Keeping Fingerprints & Dna Samples Of Criminal Suspects, K. Michael, Clive Harfield

Clive Harfield

In England and Wales, the Police and Criminal Evidence Act 1984 (the PACE) contained powers for the taking of fingerprints, and samples in the form of deoxyribonucleic acid (DNA). In 2001, Section 64(1A) of the PACE was substituted with Section 82 of the Criminal Justice and Police Act. The change to legislation meant that a suspect of a crime would have their fingerprints and samples permanently stored on the police national computer (PNC) even after having been acquitted. This paper critically analyses the circumstances of the landmark case of S. AND MARPER V. THE UNITED KINGDOM in two different contexts …

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An H1 Model For Inextensible Strings, Stephen Preston, Ralph Saxton Feb 2013

An H1 Model For Inextensible Strings, Stephen Preston, Ralph Saxton

Ralph Saxton

We study geodesics of the H1 Riemannian metric (see article for equation) on the space of inextensible curves (see article for equation). This metric is a regularization of the usual L2 metric on curves, for which the submanifold geometry and geodesic equations have been analyzed already. The H1 geodesic equation represents a limiting case of the Pochhammer-Chree equation from elasticity theory. We show the geodesic equation is C∞ in the Banach topology C1 ([0,1], R2), and thus there is a smooth Riemannian exponential map. Furthermore, if we hold one of the curves fixed, we have global-in-time solutions. We conclude with …

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Image Analysis Using Line Segments Extraction By Chain Code Differentiation, A. Chalechale, G. Naghdy, Prashan Premaratne Jan 2013

Image Analysis Using Line Segments Extraction By Chain Code Differentiation, A. Chalechale, G. Naghdy, Prashan Premaratne

Dr Prashan Premaratne

This paper proposes a new fast method for line segment extraction from edge maps. It has a parallel nature and can be used on parallel machines easily. The method uses the chain codes in the edge map, namely macrochains, for line segment detection. In the first phase, it breaks the macrochains into several microchains by employing the extreme points of the first derivative of shifted-smoothed chain code function. Straight-line segments approximate the resulting microchains. In the second phase, the line segments are grouped together based on their proximity (collinearity and nearness) to make longer segments. The final set could be …

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Evaluation Of Student Outcomes In Online Vs. Campus Biostatistics Education In A Graduate School Of Public Health, John Mcgready, Ron Brookmeyer Jan 2013

Evaluation Of Student Outcomes In Online Vs. Campus Biostatistics Education In A Graduate School Of Public Health, John Mcgready, Ron Brookmeyer

Ron Brookmeyer

Objective: To compare student outcomes between concurrent online and on-campus sections of an introductory biostatistics course offered at a U.S. school of public health in 2005. Methods: Enrolled students (95 online, 92 on-campus) were invited to participate in a confidential online survey. The course outcomes were compared between the two sections adjusting for differences in student characteristics. Results: Seventy-two online (76%) and 66 (72%) on-campus enrollees participated. Unadjusted final exam scores for the online and on-campus sections were respectively 85.1 and 86.3 (p = 0.50) in term 1, and 87.7 and 86.9 (p=0.58) in term 2. After adjustment for student …

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Space-Time Signal Processing For Distributed Pattern Detection In Sensor Networks, Randy Paffenroth, Philip Du Toit, Louis Scharf, Anura Jayasumana, Vidarshana Banadara, Ryan Nong Jan 2013

Space-Time Signal Processing For Distributed Pattern Detection In Sensor Networks, Randy Paffenroth, Philip Du Toit, Louis Scharf, Anura Jayasumana, Vidarshana Banadara, Ryan Nong

Randy C. Paffenroth

We present a theory and algorithm for detecting and classifying weak, distributed patterns in network data that provide actionable information with quantiable measures of uncertainty. Our work demonstrates the eectiveness of space-time inference on graphs, robust matrix completion, and second order analysis for the detection of distributed patterns that are not discernible at the level of individual nodes. Motivated by the importance of the problem, we are specically interested in detecting weak patterns in computer networks related to Cyber Situational Awareness. Our focus is on scenarios where the nodes (terminals, routers, servers, etc.) are sensors that provide measurements (of packet …

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Human Resource Information Systems: Information Security Concerns For Organizations, Humayun Zafar Jan 2013

Human Resource Information Systems: Information Security Concerns For Organizations, Humayun Zafar

Humayun Zafar

We explore HRIS and e-HR security by presenting information security fundamentals and how they pertain to organizations. With increasing use of enterprise systems such as HRIS and e-HR, security of such systems is an area that is worthy of further exploration. Even then, there is surprisingly little research in this area, albeit that extensive work is present in regard to HRIS privacy. While focusing on HRIS and e-HR security, we introduce aspects of HRIS and e-HR security and how it can be enhanced in organizations. A research model is also presented along with propositions that can guide future research.

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Activating The Teaching-Research Nexus In Smaller Universities: Case Studies Highlighting Diversity Of Practice, William Boyd, Meg O'Reilly, Daniel Bucher, Kath Fisher, Anja Morton, Peter Harrison, Elaine Nuske, Rebecca Coyle, Karyn Rendall Jan 2013

Activating The Teaching-Research Nexus In Smaller Universities: Case Studies Highlighting Diversity Of Practice, William Boyd, Meg O'Reilly, Daniel Bucher, Kath Fisher, Anja Morton, Peter Harrison, Elaine Nuske, Rebecca Coyle, Karyn Rendall

Dr Rebecca Coyle

The teaching-research nexus (TRN) has become an important process in the modern University, providing both identity to university scholarship and a device for the integration of academics’ work. Over the last decade many reports have identified the need to both establish institution-wide processes to embed and support TRN, and assist in academic professional development in adopting TRN. This case study reports one such institutional project, focussing on one element of the staff development program, a TRN panel discussion by academics who have engaged TRN. The discussion was structured around the five TRN dimensions of: Learning through research; Research-led teaching; Researching …

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Iron And Arsenic Cycling In Intertidal Surface Sediments During Wetland Remediation, Scott Johnston, Annabelle Keene, Edward Burton, Richard Bush, Leigh Sullivan Jan 2013

Iron And Arsenic Cycling In Intertidal Surface Sediments During Wetland Remediation, Scott Johnston, Annabelle Keene, Edward Burton, Richard Bush, Leigh Sullivan

Associate Professor Edward D Burton

The accumulation and behavior of arsenic at the redox interface of Fe-rich sediments is strongly influenced by Fe(III) precipitate mineralogy, As speciation, and pH. In this study, we examined the behavior of Fe and As during aeration of natural groundwater from the intertidal fringe of a wetland being remediated by tidal inundation. The groundwater was initially rich in Fe2+ (32 mmol L−1) and As (1.81 μmol L−1) with a circum-neutral pH (6.05). We explore changes in the solid/solution partitioning, speciation and mineralogy of Fe and As during long-term continuous groundwater aeration using a combination of chemical extractions, SEM, XRD, and …

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Mapping Same-Sex Couple Family Households In Australia, Andrew Gorman-Murray, Christopher Brennan-Horley, Kirsten Mclean, Gordon Waitt, Christopher Gibson Jan 2013

Mapping Same-Sex Couple Family Households In Australia, Andrew Gorman-Murray, Christopher Brennan-Horley, Kirsten Mclean, Gordon Waitt, Christopher Gibson

Christopher R Brennan-Horley

The map (1:1,218,987) accompanying this report is the first to depict the distribution of same-sex couple family households across Australia. The map and the report contribute to emerging scholarship combining critical geographies of sexualities with quantitative techniques and GIS in order to advance the political claims of sexual minorities. The data were collected through the 2006 Census and obtained via consultation with the Australian Bureau of Statistics. These data included the number of same-sex couple family households for all Statistical Divisions across Australia and for Statistical Sub-Divisions within metropolitan capital cities. Geographical concentrations of same-sex couple family households were determined …

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Molluscan Remains From Fiji, Katherine Szabo Jan 2013

Molluscan Remains From Fiji, Katherine Szabo

Katherine A Szabo

Shell recovered from archaeological sites can give valuable insight to issues of site formation, taphonomy, subsistence, the nature of the environment and environmental change over time. Here, I present a series of shell analyses that can assist in the investigation of several research issues, focusing primarily on ecological issues.

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Photoexcitation And Photoionization From The 2p53p[5/2]2,3 Levels In Neon, M. Baig, I. Bokhari, M. Rafiq, M. Kalyar, T. Hussian, Raheel Ali, Naveed Piracha Jan 2013

Photoexcitation And Photoionization From The 2p53p[5/2]2,3 Levels In Neon, M. Baig, I. Bokhari, M. Rafiq, M. Kalyar, T. Hussian, Raheel Ali, Naveed Piracha

Naveed K. Piracha

We present measurements of the excitation spectra from the 2p53p [5/2]3,2 levels in neon using two-step laser excitation and ionization in conjunction with an optogalvanic detection in dc and rf discharge cells. The 2p53p [5/2]3,2 intermediate levels have been approached via the collisionally populated 2p53s [3/2]2 metastable level. The Rydberg series 2p5(2P3/2)nd [7/2]4 (12 ⩽ n ⩽ 44), 2p5(2P3/2)ns [3/2]2 (13 ⩽ n ⩽ 35) and the parity forbidden transitions 2p5(2P3/2)np [5/2]3 (13 ⩽ n ⩽ 19) have been observed from the 2p53p [5/2]3 level, whereas the 2p5(2P3/2)nd [7/2]3 (12 ⩽ n ⩽ 44), 2p5(2P3/2)ns [3/2]2 (13 ⩽ n ⩽ …

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Fluorescent Ratiometric Indicators Based On Cu(Ii)-Induced Changes In Poly(Nipam) Microparticle Volume, Shawn Burdette, John Osambo, W.Rudolf Seitz, Daniel Kennedy, Roy Planalp, Aaron Jones, Randy Jackson Jan 2013

Fluorescent Ratiometric Indicators Based On Cu(Ii)-Induced Changes In Poly(Nipam) Microparticle Volume, Shawn Burdette, John Osambo, W.Rudolf Seitz, Daniel Kennedy, Roy Planalp, Aaron Jones, Randy Jackson

Shawn C. Burdette

Microparticles consisting of the thermal responsive polymer N-isopropyl acrylamide (polyNIPAM), a metal ion-binding ligand and a fluorophore pair that undergoes fluorescence resonance energy transfer (FRET) have been prepared and characterized. Upon the addition of Cu(II), the microparticles swell or contract depending on whether charge is introduced or neutralized on the polymer backbone. The variation in microparticle morphology is translated into changes in emission of each fluorophore in the FRET pair. By measuring the emission intensity ratio between the FRET pair upon Cu(II) addition, the concentration of metal ion in solution can be quantified. This ratiometric fluorescent indicator is the newest …

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Controls On Floc Size In A Continental Shelf Bottom Boundary Layer, Paul Hill, George Voulgaris, John Trowbridge Jan 2013

Controls On Floc Size In A Continental Shelf Bottom Boundary Layer, Paul Hill, George Voulgaris, John Trowbridge

George Voulgaris

Simultaneous in situ observations of floc size, waves, and currents in a continental shelf bottom boundary layer do not support generally accepted functional relationships between turbulence and floc size in the sea. In September and October 1996 and January 1997, two tripods were deployed in 70 m of water on the continental shelf south of Woods Hole, Massachusetts. On one a camera photographed particles in suspension 1.2 m above the bottom that had equivalent circular diameters larger than 250 um, and on the other, three horizontally displaced acoustic current meters measured flow velocity 0.35 m above the bottom. The tripods …

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Measurements And Three-Dimensional Modeling Of Nearshore Circulation On A South Carolina Beach, Nirnimesh Kumar, George Voulgaris, John Warner Jan 2013

Measurements And Three-Dimensional Modeling Of Nearshore Circulation On A South Carolina Beach, Nirnimesh Kumar, George Voulgaris, John Warner

George Voulgaris

A numerical modeling system for simulating nearshore surf zone conditions and tidal processes is presented and evaluated with in situ data. The modeling system is comprised of the Regional Ocean Modeling System (ROMS v 3.0), a three-dimensional numerical ocean model, coupled with Simulating Waves Nearshore (SWAN), a spectral wave propagation model. The system has been modified with a new vertical distribution of radiation stress terms for applications in very shallow waters. The model performance is evaluated by comparing simulations to hydrodynamic data (wave height, direction, longshore and cross-shore currents) collected in the surf zone in northern South Carolina, U.S. Model …

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Cross-Shore Variation Of Wind-Driven Flows On The Inner Shelf In Long Bay, South Carolina, United States, Benjamin Gutierrez, George Voulgaris, Paul Work Jan 2013

Cross-Shore Variation Of Wind-Driven Flows On The Inner Shelf In Long Bay, South Carolina, United States, Benjamin Gutierrez, George Voulgaris, Paul Work

George Voulgaris

The cross-shore structure of subtidal flows on the inner shelf (7 to 12 m water depth) of Long Bay, South Carolina, a concave-shaped bay, is examined through the analysis of nearly 80 days of near-bed (1.7–2.2 m above bottom) current observations acquired during the spring and fall of 2001. In the spring and under northeastward winds (upwelling favorable) a two-layered flow was observed at depths greater than 10 m, while closer to the shore the currents were aligned with the wind. The two-layered flow is attributed to the presence of stratification, which has been observed under similar conditions in the …

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Geomorphic Analysis Of Tidal Creek Networks, Karyn Novakowski, Raymond Torres, L Gardner, George Voulgaris Jan 2013

Geomorphic Analysis Of Tidal Creek Networks, Karyn Novakowski, Raymond Torres, L Gardner, George Voulgaris

George Voulgaris

The purpose of this study is to determine if concepts in terrestrial channel network analysis provide insight on intertidal creek network development and to present new metrics for their analysis. We delineated creek network geometry using high-resolution digital images of intertidal marsh near Georgetown, South Carolina. Analyses reveal that intertidal creek networks may be topologically random. Length-area relationships suggest that salt marsh and terrestrial networks have similar scaling properties, although the marsh networks are more elongate than terrestrial networks. To account for recurrent water exchange between creek basins at high tide, we propose that the landscape unit of geomorphic analyses …

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Effects Of Low Tide Rainfall On Intertidal Zone Material Cycling, Raymond Torres, Miguel Goni, George Voulgaris, Charles Lovell, James Morris Jan 2013

Effects Of Low Tide Rainfall On Intertidal Zone Material Cycling, Raymond Torres, Miguel Goni, George Voulgaris, Charles Lovell, James Morris

George Voulgaris

Sediment transport by rainfall-runoff processes is well documented for terrestrial landscapes but few studies have focused on rainfall-runoff effects in intertidal areas. Here we present geochemical analyses performed on sediment samples collected during low tide irrigation experiments, and tidal channel turbidity measurements taken during natural rainfall over North Inlet Marsh, South Carolina. Order of magnitude approximations indicate that a single 10 minute storm may entrain 8-15% of the local annual average sediment accumulation. This rainfall-entrained material is enriched in organic nitrogen and marine algal matter, and therefore of high nutritional quality.

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Evaluation Of The Acoustic Doppler Velocimeter (Adv) For Turbulence Measurements, George Voulgaris, John Trowbridge Jan 2013

Evaluation Of The Acoustic Doppler Velocimeter (Adv) For Turbulence Measurements, George Voulgaris, John Trowbridge

George Voulgaris

Accuracy of the acoustic Doppler velocimeter (ADV) is evaluated in this paper. Simultaneous measurements of open-channel flow were undertaken in a 17-m flume using an ADV and a laser Doppler velocimeter. Flow velocity records obtained by both instruments are used for estimating the true (‘‘ground truth’’) flow characteristics and the noise variances encountered during the experimental runs. The measured values are compared with estimates of the true flow characteristics and values of variance (^u92&, ^w92&) and covariance (^u9w9&) predicted by semiempirical models for open-channel flow. The analysis showed that the ADV sensor can measure mean velocity and Reynolds stress within …

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Forcing And Dynamics Of Seafloor-Water Column Exchange On A Broad Continental Shelf, William Savidge, Ann Gargett, Richard Jahnke, James Nelson, Dana Savidge, R Short, George Voulgaris Jan 2013

Forcing And Dynamics Of Seafloor-Water Column Exchange On A Broad Continental Shelf, William Savidge, Ann Gargett, Richard Jahnke, James Nelson, Dana Savidge, R Short, George Voulgaris

George Voulgaris

Relict sediments of elevated permeability characterize the majority of continental shelves globally (Emery, 1968). In these settings, interactions between benthic boundary layer (BBL) flows and seabed topography generate pressure fluctuations that drive advective and dispersive porewater transport, dramatically increasing the magnitude and variability of porewater solute and particulate exchange across the sediment-water interface (Huettel et al., 1996; Huettel and Rusch, 2000). On broad shallow shelves with a relatively large area-to-volume ratio, the seafloor’s role is magnified. Energetic events may reorganize bedforms across a significant fraction of the shelf, leading to altered exchange dynamics that may persist long after the organizing …

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Tidal Asymmetry And Residual Circulation Over Linear Sandbanks And Their Implication On Sediment Transport: A Process-Oriented Numerical Study, Rosario Sanay, George Voulgaris, John Warner Jan 2013

Tidal Asymmetry And Residual Circulation Over Linear Sandbanks And Their Implication On Sediment Transport: A Process-Oriented Numerical Study, Rosario Sanay, George Voulgaris, John Warner

George Voulgaris

A series of process-oriented numerical simulations is carried out in order to evaluate the relative role of locally generated residual flow and overtides on net sediment transport over linear sandbanks. The idealized bathymetry and forcing are similar to those present in the Norfolk Sandbanks, North Sea. The importance of bottom drag parameterization and bank orientation with respect to the ambient flow is examined in terms of residual flow and overtide generation, and subsequent sediment transport implications are discussed. The results show that although the magnitudes of residual flow and overtides are sensitive to bottom roughness parameterization and bank orientation, the …

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Shelf Edge Tide Correlated Eddies Along The Southeastern United States, Dana Savidge, Jonathan Norman, Colton Smith, Julie Amft, Trent Moore, Catherine Edwards, George Voulgaris Jan 2013

Shelf Edge Tide Correlated Eddies Along The Southeastern United States, Dana Savidge, Jonathan Norman, Colton Smith, Julie Amft, Trent Moore, Catherine Edwards, George Voulgaris

George Voulgaris

High frequency radar observations in the Southeastern United States have revealed sequences of small short‐lived cyclonic eddies along the shoreward edge of the Gulf Stream, that spin up as the local tide turns alongshelf antiparallel to the Stream. Eddies propagate equatorward along the shelf edge, sometimes progressing shoreward before dissipating one to three hours later. They are distinctly different from Gulf Stream meander eddies, which propagate poleward. In this article, radar and mooring data are used to establish three important aspects of these neweddies: they represent an instability process operating at a previously unidentified frequency, scale, and cross‐Stream position; they …

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Wind Speed Dependence Of Single-Site Wave-Height Retrievals From High-Frequency Radars, Brian Haus, Lynn Shay, Paul Work, George Voulgaris, Rafael Ramos, Jorge Martinez-Pedraja Jan 2013

Wind Speed Dependence Of Single-Site Wave-Height Retrievals From High-Frequency Radars, Brian Haus, Lynn Shay, Paul Work, George Voulgaris, Rafael Ramos, Jorge Martinez-Pedraja

George Voulgaris

Wave-height observations derived from single-site high-frequency (HF) radar backscattered Doppler spectra are generally recognized to be less accurate than overlapping radar techniques but can provide significantly larger sampling regions. The larger available wave-sampling region may have important implications for observing system design. Comparison of HF radar–derived wave heights with acoustic Doppler profiler and buoy data revealed that the scale separation between the Bragg scattering waves and the peak energy-containing waves may contribute to errors in the single-site estimates in light-to-moderate winds. A wave-height correction factor was developed that explicitly considers this scale separation and eliminates the trend of increasing errors …

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Subtidal Inner Shelf Currents Off Cartagena De Indias, Caribbean Coast Of Colombia, Mauro Maza, George Voulgaris, Bulusu Subrahmanyam Jan 2013

Subtidal Inner Shelf Currents Off Cartagena De Indias, Caribbean Coast Of Colombia, Mauro Maza, George Voulgaris, Bulusu Subrahmanyam

George Voulgaris

Seasonal trends in inner shelf subtidal circulation off the coast of Cartagena de Indias, Colombia, are examined through the analysis of current profiles, hydrographic, meteorological and satellite data collected from 1999 to 2002. During the dry season (December–April) the water column is well-mixed and along-shelf currents flow southwestward following the steady trade winds. In the rainy season (May –November) the water column experiences continuous events of stratification and the along-shelf currents flow northeastward, opposing the weak southwestward winds. In the dry season the along shelfcirculation is mostly driven by wind forcing, while in the rainy season, the circulation is set …

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Estimation Of Hiv Incidence Using Multiple Biomakers, Ron Brookmeyer, Jacob Konikoff, Oliver Laeyendecker, Susan Eshleman Jan 2013

Estimation Of Hiv Incidence Using Multiple Biomakers, Ron Brookmeyer, Jacob Konikoff, Oliver Laeyendecker, Susan Eshleman

Ron Brookmeyer

The incidence of human immunodeficiency virus (HIV) is the rate at which new HIV infections occur in populations. The development of accurate, practical, and cost-effective approaches to estimation of HIV incidence is a priority among researchers in HIV surveillance because of limitations with existing methods. In this paper, we develop methods for estimating HIV incidence rates using multiple biomarkers in biological samples collected from a cross-sectional survey. An advantage of the method is that it does not require longitudinal follow-up of individuals. We use assays for BED, avidity, viral load, and CD4 cell count data from clade B samples collected …

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Development Of A New Lagrangian Float For Studying Coastal Marine Ecosystems, Alex Schwithal, Chris Roman Jan 2013

Development Of A New Lagrangian Float For Studying Coastal Marine Ecosystems, Alex Schwithal, Chris Roman

Christopher N. Roman

This paper presents an overview and initial testing results for a shallow water Lagrangian float designed to operate in coastal settings. The presented effort addresses the two main characteristics of the shallow coastal environment that preclude the direct of use of many successfully deep water floats, namely the higher variation of water densities near the coast compared with the open ocean and the highly varied bathymetry. Our idea is to develop a high capacity dynamic auto-ballasting system that is able to compensate for the expected seawater density variation over a broad range of water temperatures and salinities while using measurements …

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Hx, A Novel Fluorescent, Minor Groove And Sequence Specific Recognition Element: Design, Synthesis, And Dna Binding Properties Of P-Anisylbenzimidazole-Imidazole/Pyrrole-Containing Polyamides, Sameer Chavda, Yang Liu, Balaji Babu, Ryan Davis, Alan Sielaff, Jennifer Ruprich, Laura Westrate, Christopher Tronrud, Amanda Ferguson, Andrew Franks, Samuel Tzou, Chandler Adkins, Toni Rice, Hilary Mackay, Jerome Kluza, Sharjeel Tahir, Shicai Lin, Konstantinos Kiakos, Chrystal Bruce, W. Wilson, John Hartley, Moses Lee Jan 2013

Hx, A Novel Fluorescent, Minor Groove And Sequence Specific Recognition Element: Design, Synthesis, And Dna Binding Properties Of P-Anisylbenzimidazole-Imidazole/Pyrrole-Containing Polyamides, Sameer Chavda, Yang Liu, Balaji Babu, Ryan Davis, Alan Sielaff, Jennifer Ruprich, Laura Westrate, Christopher Tronrud, Amanda Ferguson, Andrew Franks, Samuel Tzou, Chandler Adkins, Toni Rice, Hilary Mackay, Jerome Kluza, Sharjeel Tahir, Shicai Lin, Konstantinos Kiakos, Chrystal Bruce, W. Wilson, John Hartley, Moses Lee

Chrystal D. Bruce

With the aim of incorporating a recognition element that acts as a fluorescent probe upon binding to DNA, three novel pyrrole (P) and imidazole (I)-containing polyamides were synthesized. The compounds contain a p-anisylbenzimidazolecarboxamido (Hx) moiety attached to a PP, IP, or PI unit, giving compounds HxPP (2), HxIP (3), and HxPI (4), respectively. These fluorescent hybrids were tested against their complementary nonfluorescent, non-formamido tetraamide counterparts, namely, PPPP (5), PPIP (6), and PPPI (7) (cognate sequences 5'-AAATTT-3', 5'-ATCGAT-3', and 5'-ACATGT-3', respectively). The binding affinities for both series of polyamides for their cognate and noncognate sequences were ascertained by surface plasmon resonance …

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