Physical Sciences and Mathematics Commons^™

Quantifying An Adherence Path-Specific Effect Of Antiretroviral Therapy In The Nigeria Pepfar Program, Caleb Miles, Ilya Shpitser, Phyllis Kanki, Seema Meloni, Eric J. Tchetgen Tchetgen

Harvard University Biostatistics Working Paper Series

No abstract provided.

On The Restricted Mean Survival Time Curve Survival Analysis, Lihui Zhao, Brian Claggett, Lu Tian, Hajime Uno, Marc A. Pfeffer, Scott D. Solomon, Lorenzo Trippa, L. J. Wei

Harvard University Biostatistics Working Paper Series

No abstract provided.

A Sheet On Deformable Sphere: "Wrinklogami" Patterns Suppress Curvature-Induced Delamination, Evan Hohlfeld, Benny Davidovitch

Benny Davidovitch

No abstract provided.

A Review Of Software For Analyzing Molecular Sequences, Haema Nilakanta, Kimberly L. Drews, Suzanne Firrell, Mary A. Foulkes, Kathleen A. Jablonski

GW Biostatistics Center

Background Over the past ten years, there has been an explosion of microbiome research. Many software packages for analyzing microbial sequences such as the 16S gene from 454 sequencers and Illumina platforms are available. But for a new researcher, it is difficult to know which package to choose. We present a systematic review of packages for the analysis of molecular sequences used to describe and compare microbial communities. This review gives students and researchers information to help choose the best analytic pipeline for their project. To the best of our knowledge, this is the first review of such software.

Findings …

Controls On Syenite-Hosted Gold Mineralization In The Western Timmins Camp, Robert A. Campbell

Electronic Thesis and Dissertation Repository

The Abitibi granite-greenstone belt has long been known for its’ world-class Archean

lode gold deposits. With exploration and production commencing in the early nineteen

hundreds and continuing into the twenty-first century, this prolific mining camp is rich

in history, research and precious/base metals. The Thunder Creek deposit and Hwy-144 gold prospect are two recently discovered and exploited syenite associated gold plays in the Timmins Camp. The research compares the Thunder Creek and Hwy-144 properties providing new observations on the variable mechanisms for gold mineralization that can change over a short strike distance (0.5-1.5 km’s) hosted in a geologically similar environment. …

Free-Standing Inflatable Solar Chimney: Experiment And Theory, Peter Vorobieff, Andrea Mammoli, Nima Fathi, Vakhtang Putkaradze

Nima Fathi

Stilling Basin Performance Analysis By Adv, Seyed Sobhan Aleyasin, Nima Fathi, Peter Vorobieff

Nima Fathi

The Detection Of Peroxynitrite Using 19f Magnetic Resonance Probes, Kevin Bruemmer

Collection of Engaged Learning

The following report presents the work done by Kevin Bruemmer for his Engaged Learning project. The 19F magnetic resonance probes 5-uoroisatin and 6-uoroisatin were reacted with ONOO- to yield anthranilic acid derivatives through a novel oxidative decarbonyaltion reaction. Utilizing 19F NMR spectroscopy techniques, the presence of ONOO- can be determined through a chemical shift switching signal. 5-uoroisatin was subsequently used to detect ONOO- in living lung epithelial cells.

Synthesis Of Hydrogenated Thiol-Silanes For Selective Reactions, Macartney Welborn

Collection of Engaged Learning

The intention of this experiment is to show the creation of multifunctional thiols from the reaction between various hydrochlorosilanes and mercaptoethanol in an attempt to utilize their distinct properties for practical applications. Multifunctional thiols have many useful applications including use in high-refractive-index lenses, ¹ heavy metal chelation, ² and degradable plastics³. Previous work, ⁵ in our lab has explored a class of reactions key to the synthesis of these compounds: the reaction between methylated chlorosilanes with mercaptoalcohols. We extended this reaction to include hydrogenated chlorosilanes. This allows us to produce multifunctional thiols with an additional functionalizable position at …

The Number Of Framings Of A Knot In A 3-Manifold, Patricia Cahn, Vladimir Chernov, Rustam Sadykov

Mathematics Sciences: Faculty Publications

In view of the self-linking invariant, the number |K| of framed knots in S3 with given underlying knot K is infinite. In fact, the second author previously defined affine self-linking invariants and used them to show that |K| is infinite for every knot in an orientable manifold unless the manifold contains a connected sum factor of S1 × S2; the knot K need not be zero-homologous and the manifold is not required to be compact. We show that when M is orientable, the number |K| is infinite unless K intersects a nonseparating sphere at exactly one point, in which case …

Exact P-Adic Orders For Differences Of Motzkin Numbers, Tamas Lengyel

Tamas Lengyel

For any prime p, we establish congruences modulo pn+1 for the difference of the pn+1th and pnth Motzkin numbers and determine the p-adic order of the difference. The results confirm recent conjectures on the order. The applied techniques involve the use of congruences for the differences of certain Catalan numbers and binomial coefficients, congruential identities for sums of Catalan numbers, central binomial and trinomial coefficients, infinite incongruent disjoint covering systems and the solution of congruential recurrences.

Fearless Friday: Sean Pethybridge, Christina L. Bassler

SURGE

Talking with Sean Pethybridge ’15, one could easily assume his interest in agriculture and food justice developed at a very young age. Sean confesses that he had very limited knowledge prior to attending Gettysburg. “My grandpa had a garden and the most experience I had with that was picking green beans during the summer time when I was younger,” he jokes. [excerpt]

Chemical Potential In The First Law For Holographic Entanglement Entropy, David Kastor, Sourya Ray, Jennie Traschen

David Kastor

Entanglement entropy in conformal field theories is known to satisfy a first law. For spherical entangling surfaces, this has been shown to follow via the AdS/CFT correspondence and the holographic prescription for entanglement entropy from the bulk first law for Killing horizons. The bulk first law can be extended to include variations in the cosmological constant Λ, which we established in earlier work. Here we show that this implies an extension of the boundary first law to include varying the number of degrees of freedom of the boundary CFT. The thermodynamic potential conjugate to Λ in the bulk is called …

Line-Driven Radiative Outflows In Luminous Quasars, Rebecca A. A. Bowler, Paul C. Hewett, James T. Allen, Gary J. Ferland

Physics and Astronomy Faculty Publications

An analysis of ≃19 500 narrow ( ≲ 200 km s⁻¹) C iv λλ1548.2,1550.8 absorbers in ≃34 000 Sloan Digital Sky Survey quasar spectra is presented. The statistics of the number of absorbers as a function of outflow velocity shows that in approximately two-thirds of outflows, with multiple C iv absorbers present, absorbers are line-locked at the 500 km s⁻¹ velocity separation of the C iv absorber doublet; appearing as ‘triplets’ in the quasar spectra. Line-locking is an observational signature of radiative line-driving in outflowing material, where the successive shielding of ‘clouds’ of material in the outflow …

Comment On “Chemically Mediated Behavior Of Recruiting Corals And Fishes: A Tipping Point That May Limit Reef Recovery”, Andrew H. Baird, Vivian R. Cumbo, Joana Figueiredo, Saki Harii, Tom Hata, Joshua S. Madin

Marine & Environmental Sciences Faculty Articles

Dixson et al. (2014) report that coral larvae navigate towards chemical cues associated with healthy reefs and avoid cues from degraded reefs. However, the swimming capabilities of coral larvae and well-established patterns of recruitment and reef hydrodynamics indicate that coral larvae will not be able to use these cues to recruit to healthy reefs. Perfuming degraded reefs, as suggested by Dixson et al (2014), will not enhance recovery rather it will distract from the difficult task of reducing fishing effort and improving water quality.

Chemistry Graduate Teaching Assistants' Experiences In Academic Laboratories And Development Of A Teaching Self-Image, Todd Adam Gatlin

USF Tampa Graduate Theses and Dissertations

Graduate teaching assistants (GTAs) play a prominent role in chemistry laboratory instruction at research based universities. They teach almost all undergraduate chemistry laboratory courses. However, their role in laboratory instruction has often been overlooked in educational research. Interest in chemistry GTAs has been placed on training and their perceived expectations, but less attention has been paid to their experiences or their potential benefits from teaching.

This work was designed to investigate GTAs' experiences in and benefits from laboratory instructional environments. This dissertation includes three related studies on GTAs' experiences teaching in general chemistry laboratories. Qualitative methods were used for each …

Effects Of Ocean Acidification On The Dissolution Rates Of Reef-Coral Skeletons, Robert Van Woesik, Kelly Van Woesik, Liana Van Woesik, Sandra Van Woesik

Ocean Engineering and Marine Sciences Faculty Publications

Ocean acidification threatens the foundation of tropical coral reefs. This study investigated three aspects of ocean acidification: (i) the rates at which perforate and imperforate coral-colony skeletons passively dissolve when pH is 7.8, which is predicted to occur globally by 2100, (ii) the rates of passive dissolution of corals with respect to coral-colony surface areas, and (iii) the comparative rates of a vertical reef-growth model, incorporating passive dissolution rates, and predicted sea-level rise. By 2100, when the ocean pH is expected to be 7.8, perforate Montipora coral skeletons will lose on average 15 kg CaCO3 m􀀀2 y􀀀1, which is approximately …

Dynamic Resource Management In Virtualized Data Centres, Gaston Keller

Electronic Thesis and Dissertation Repository

In the last decade, Cloud Computing has become a disruptive force in the computing landscape, changing the way in which software is designed, deployed and used over the world. Its adoption has been substantial and it is only expected to continue growing. The growth of this new model is supported by the proliferation of large-scale data centres, built for the express purpose of hosting cloud workloads. These data centres rely on systems virtualization to host multiple workloads per physical server, thus increasing their infrastructures' utilization and decreasing their power consumption. However, the owners of the cloud workloads expect their applications' …

Allostratigraphy Of The Upper Ordovician Blue Mountain Formation, Southwestern Ontario, Canada, Sarah N. Sweeney

Electronic Thesis and Dissertation Repository

The Upper Ordovician units in Southwestern Ontario record the distal response to the development of the Taconic Appalachian foreland basin. The proximal representation in Ohio and Pennsylvania, contain the Utica/Point Pleasant Play (!). The relationship between the proximal and distal portions of the Taconic Appalachian foreland basin is not clearly defined due to limited chronostratigraphic data and only lithostratigraphic correlations in southwestern Ontario. The first step in evaluating the relationship between the Upper Ordovician succession in Ontario and that in the United States is to develop a high frequency allostratigraphic framework that can be integrated and compared to the frameworks …

Confined Mesoscopic Fluid-Like Films Analyzed With Frequency Modulation And Acoustic Detection, Rodolfo Fernandez Rodriguez

Dissertations and Theses

Complete understanding of the physics underlying the changes in viscoelasticity, relaxation time, and phase transitions that mesoscopic fluid-like systems undergo at solid-liquid interfaces or under confinement remains one of the major challenges in condensed matter physics. Moreover, studies of confined mesoscopic fluid films are relevant to technological areas like adhesion, wetting processes and nanotribology.

This thesis addresses the interaction between two sliding solids interfaces separated by a nanometer sized gap, with emphasis on the role of the mesoscopic fluid film trapped between them. For this purpose we integrated two acoustic techniques, recently introduced by our group, into a sub-nanometer precision …

Can Xrf Scanning Of Speleothems Be Used As A Non-Destructive Method To Identify Paleoflood Events In Caves?, Martin Finné, Malin Kylander, Meighan Boyd, Hanna S. Sundqvist, Ludvig Löwemark

International Journal of Speleology

We have developed a novel, quick and non-destructive method for tracing flood events in caves through the analysis of a stalagmite thick section with an XRF core scanner. The analyzed stalagmite has multiple horizons of fine sediments from past flood events intercalated with areas of cleaner calcite. Flood events detected from the elemental XRF core scanning data show good agreement with the position of flood horizons identified in petrographic thin sections. The geochemical composition of the individual flood layers shows that in certain cases the clay horizons had a distinct geochemical fingerprint suggesting that it may be possible to distinguish …

Microstratigraphic Logging Of Calcite Fabrics In Speleothems As Tool For Palaeoclimate Studies, Silvia Frisia

International Journal of Speleology

The systematic documentation of calcite fabrics in stalagmites and flowstones provides robustness to palaeoclimate interpretation based on geochemical proxies, but it has been neglected because it is difficult to transform crystal morphologies into numerical values, and construct fabric time series. Here, general criteria that allow for coding fabrics of calcite composing stalagmites and flowstones is provided. Being based on known models of fabric development, the coding ascribes sequential numbers to each fabric, which reflect climate-related parameters, such as changes in drip rate variability, bio-mediation or diagenetic modifications. Acronyms are proposed for Columnar types, Dendritic, Micrite, Microsparite and Mosaic fabrics, whose …

Leadership - A Lifetime Quest For Excellence, Douglas D. Piirto

Natural Resources Management and Environmental Sciences

This paper is written for aspiring leaders and managers. Each of us will be asked to lead, manage, and/or follow at various times and in many different situations in our journey of life. This paper is written to assist aspiring leaders and managers discover and develop their leadership and management abilities.

The paper is organized per the following outline:

• Introduction
• Establishing Credibility
• Enthusiasm and Desirable Habits of Effective People
• Leadership and Management
• Situational Analysis and Leadership Styles
• Leadership as a Student [discussed in Introduction)
• Leadership as a Forest Scientist
• Leadership as a Teacher and Professor
• Leadership as a Department Head …

Population Genetics Of Seaside Sparrow (Ammodramus Maritimus) Subspecies Along The Gulf Of Mexico., Stefan Woltmann, Phillip C. Stouffer, Christine M. Bergeon Burns, Mark S. Woodrey, Mollie F. Cashner, Sabrina S. Taylor

Coastal Research and Extension Center Publications

Seaside Sparrows (Ammodramus maritimus) along the Gulf of Mexico are currently recognized as four subspecies, including taxa in Florida (A. m. juncicola and A. m. peninsulae) and southern Texas (Ammodramus m. sennetti), plus a widespread taxon between them (A. m. fisheri). We examined population genetic structure of this "Gulf Coast" clade using microsatellite and mtDNA data. Results of Bayesian analyses (Structure, GeneLand) of microsatellite data from nine locations do not entirely align with current subspecific taxonomy. Ammodramus m. sennetti from southern Texas is significantly differentiated from all other populations, but we found evidence of an admixture zone with A. m. …

The Fierce Green Fire: Vol 5 Issue 10, Wofford College Environmental Studies Program

The Fierce Green Fire

No abstract provided.

The Critical Role Of Cubesat Spacecraft In A Multi-Tier Mission For Mars Exploration, Jeremy Straub

Jeremy Straub

A multi-tier architecture is under development (with similar craft heterogeneity to Fink's work on ‘tier scalable’ missions) which will facilitate autonomous local control of multiple heterogeneous craft. This mission architecture has been developed with a Mars mission in mind and has included CubeSats in a variety of critical mission roles.

Two concepts will be presented: the addition of CubeSats to a larger-scale multi-tier mission, where the CubeSats serve a supporting role and a mission driven by CubeSat orbital capabilities. In the first, CubeSats are utilized to augment the area of spatial coverage that can be obtained and the temporal coverage …

Exploring Variability In Population Dynamics And The Influence Of Environmental Factors On Recruitment Of An Estuarine Fish, Elizabeth Herdter Smith

USF Tampa Graduate Theses and Dissertations

The focus of this dissertation was to explore variability in population dynamics and environmental factors influential to recruitment of spotted seatrout in Florida with the end goal of testing the incorporation of select environmental variables into the current regional stock assessment models for spotted seatrout. In Chapter 2, I compared the age and size structure of six estuary populations of this species and determined whether there was significant spatial covariation in recruitment. The results of this chapter indicated that the dynamics of each local estuary population are governed more likely by environmental factors than genetic similarities. Further, they suggest that …

Top Of The Order: Modeling The Optimal Locations Of Minor League Baseball Teams, W. Coleman Conley

Undergraduate Economic Review

Over the last twenty-five years, minor league baseball franchises have defined firm mobility. Revisiting the work of Michael C. Davis (2006), I construct a logistic regression model to predict which cities house minor league baseball teams. Six variables are tested for inclusion in the model, including population, income level, the number of major-league professional sports teams in a city, five-year population change, and distance from the closest professional team. Based on the model's predicted probabilities, cities are ranked in order of highest probability of having a team at each of the different levels from Class A to Class AAA.

High Dimensional Non-Linear Optimization Of Molecular Models, Joseph C. Fogarty

USF Tampa Graduate Theses and Dissertations

Molecular models allow computer simulations to predict the microscopic properties of macroscopic systems. Molecular modeling can also provide a fully understood test system for the application of theoretical methods. The power of a model lies in the accuracy of the parameter values which govern its mathematical behavior. In this work, a new software, called ParOpt, for general high dimensional non-linear optimization will be presented. The software provides a very general framework for the optimization of a wide variety of parameter sets. The software is especially powerful when applied to the difficult task of molecular model parameter optimization. Three applications of …

Evaluation And Application Of Instruments Measuring Spatial Ability And Attitude For College Chemistry Students, Xiaoying Xu

USF Tampa Graduate Theses and Dissertations

Student performance in college chemistry courses remains a concern for educators seeking to help improve the future STEM workforce. Besides math ability and prior chemistry knowledge, spatial ability and attitude toward chemistry have been considered as important factors influencing college chemistry performance. This work includes five studies and uses data collected from instruments to examine the relationships of these two factors - spatial ability and attitude - with student chemistry performance, and provides psychometric evidence for using the Purdue Visualization of Rotations test (ROT) and Attitude toward the Subject of Chemistry Inventory (ASCIv2) to measure these two factors, respectively, in …