Digital Commons Network^™

An Indefinite Kähler Metric On The Space Of Oriented Lines, Brendan Guilfoyle, Wilhelm Klingenberg

Publications

The total space of the tangent bundle of a Kähler manifold admits a canonical Kähler structure. Parallel translation identifies the space T of oriented affine lines in R3 with the tangent bundle of S2. Thus the round metric on S2 induces a Kähler structure on T which turns out to have a metric of neutral signature. It is shown that the identity component of the isometry group of this metric is isomorphic to the identity component of the isometry group of the Euclidean metric on R3.

The geodesics of this metric are either planes or helicoids in R3. The signature …

Wave Motion Induced By Turbulent Shear Flows Over Growing Stokes Waves, Shahrdad Sajjadi, Serena Robertson, Rebecca Harvey, Mary Brown

Publications

The recent analytical of multi-layer analyses proposed by Sajjadi et al. (J Eng Math 84:73, 2014) (SHD14 therein) is solved numerically for atmospheric turbulent shear flows blowing over growing (or unsteady) Stokes (bimodal) water waves, of low-to-moderate steepness. For unsteady surface waves, the amplitude a(t)∝ekcita(t)∝ekcit, where kcikci is the wave growth factor, k is the wavenumber, and cici is the complex part of the wave phase speed, and thus, the waves begin to grow as more energy is transferred to them by the wind. This will then display the critical height to a point, where the thickness of the inner …

Quantifying Gravity Wave Momentum Fluxes With Mesosphere Temperature Mappers And Correlative Instrumentation, David C. Fritts, Pierre-Dominique Pautet, Katrina Bossert, Michael J. Taylor, Bifford P. Williams, Hiroyuki Iimura, Tao Yuan, Nicholas J. Mitchell, Gunter Stober

Publications

An Advanced Mesosphere Temperature Mapper and other instruments at the Arctic Lidar Observatory for Middle Atmosphere Research in Norway (69.3°N) and at Logan and Bear Lake Observatory in Utah (42°N) are used to demonstrate a new method for quantifying gravity wave (GW) pseudo-momentum fluxes accompanying spatially and temporally localized GW packets. The method improves on previous airglow techniques by employing direct characterization of the GW temperature perturbations averaged over the OH airglow layer and correlative wind and temperature measurements to define the intrinsic GW properties with high confidence. These methods are applied to two events, each of which involves superpositions …

Ionospheric Signatures Of Gravity Waves Produced By The 2004 Sumatra And 2011 Tohoku Tsunamis: A Modeling Study, Michael P. Hickey, Yonghui Yu, Wenqing Wang

Publications

Ionospheric fluctuations inferred from observations of total electron content have previously been attributed to tsunamis and have confirmed the strong coupling between Earth’s ocean and ionosphere via atmospheric gravity waves (AGWs). To further advance our understanding of this wave coupling process we employ a linear full-wave model and a nonlinear time-dependent model to examine the ionospheric response to the AGW perturbations induced by the 2004 Sumatra and the 2011 Tohoku tsunamis. In the 2004 case, our modeling analyses reveal that one component of the propagating AGWs becomes dynamically unstable in the E-region ionosphere at a range exceeding 2000 km in …

The Rate Of Binary Black Hole Mergers Inferred From Advanced Ligo Observations Surrounding Gw150914, B. P. Abbott, K. Gill, B. Hughey, M. J. Szczepańczyk, M. Zanolin, Et Al.

Publications

A transient gravitational-wave signal, GW150914, was identified in the twin Advanced LIGO detectors on 2015 September 2015 at 09:50:45 UTC. To assess the implications of this discovery, the detectors remained in operation with unchanged configurations over a period of 39 days around the time of the signal. At the detection statistic threshold corresponding to that observed for GW150914, our search of the 16 days of simultaneous two-detector observational data is estimated to have a false-alarm rate (FAR) of

Characterization Of The Recombination Activities Of The Entamoeba Histolytica Rad51 Recombinase, Andrew A. Kelso, Steven D. Goodson, Suchitra Chavan, Amanda F. Say, Audrey Turchick, Deepti Sharma, Leanna L. Ledford, Erin Ratterman, Kristin Leskoske, Ada V. King, Christopher C. Attaway, Yura Bandera, Stephen H. Foulger, Alexander V. Mazin, Lesly A. Temesvari, Michael G. Sehorn

Publications

The protozoan parasite responsible for human amoebiasis is Entamoeba histolytica. An important facet of the life cycle of E. histolytica involves the conversion of the mature trophozoite to a cyst. This transition is thought to involve homologous recombination (HR), which is dependent upon the Rad51 recombinase. Here, a biochemical characterization of highly purified ehRad51 protein is presented. The ehRad51 protein preferentially binds ssDNA, forms a presynaptic filament and possesses ATP hydrolysis activity that is stimulated by the presence of DNA. Evidence is provided that ehRad51 catalyzes robust DNA strand exchange over at least 5.4 kilobase …

Big Data, Technical Communication, And The Smart City, Jordan Frith

Publications

Big data is one of the most hyped buzzwords in both academia and industry. This article makes an early contribution to research on big data by situating data theoretically as a historical object and arguing that much of the discourse about the supposed transparency and objectivity of big data ignores the crucial roles of interpretation and communication. To set forth that analysis, this article engages with recent discussion of big data and “smart” cities to show the communicative practices operating behind the scenes of large data projects and relate those practices to the profession of technical communication.

A Formative Experiment To Align Middle-School History Instruction With Literacy Goals, Jamie Colwell, David Reinking

Publications

Background/Context

Recent curricular trends based on new standards emphasize the centrality of reading and studying texts in history instruction. That trend suggests a closer alignment between middle-school history instruction and goals for developing literacy. Yet potential obstacles identified in the literature, particularly a teacher's stance toward teaching history, imply challenges to instantiating that alignment. Relatively little research has addressed how relevant conceptual positions such as disciplinary literacy might be realized in authentic practice.

Purpose/Objective

The objective was to investigate how middle-school history instruction could be transformed to align with the literacy goals addressed in new curricular standards and to better …

Power System Distributed Dynamic State Prediction, Md Ashfaqur Rahman, Ganesh Kumar Venayagamoorthy

Publications

The security of the power system can be enhanced with the prediction of the dynamic state variables. To increase the security, a distributed predictor is developed based on the Elman Recurrent Neural Network (ERNN) in this study. To develop a scalable distributed predictor, the whole network is divided in a number of ERNNs. They take the current and the previous actual states from its own and its neighbors to predict the near future values of the states. The concept is inspired from the Cellular Computational Network (CCN) framework. Each ERNN is a cell in the CCN framework. Through simulation, the …

The Economic Situation, 2016 December 1, Bruce Yandle

Publications

Quarterly report on the economic situation of the United States and South Carolina.

Tests Of Lorentz Symmetry In The Gravitational Sector, Aurélien Hees, Quentin G. Bailey, Adrien Bourgoin, Hélène Pihan-Le Bars, Christine Guerlin, Christophe Le Poncin-Lafitte

Publications

Lorentz symmetry is one of the pillars of both General Relativity and the Standard Model of particle physics. Motivated by ideas about quantum gravity, unification theories and violations of CPT symmetry, a significant effort has been put the last decades into testing Lorentz symmetry. This review focuses on Lorentz symmetry tests performed in the gravitational sector. We briefly review the basics of the pure gravitational sector of the Standard-Model Extension (SME) framework, a formalism developed in order to systematically parametrize hypothetical violations of the Lorentz invariance. Furthermore, we discuss the latest constraints obtained within this formalism including analyses of the …

Supplement: The Rate Of Binary Black Hole Mergers Inferred From Advanced Ligo Observations Surrounding Gw150914, B. P. Abbott, K. Gill, B. Hughey, M. J. Szczepańczyk, M. Zanolin, Et Al.

Publications

This article provides supplemental information for a Letter reporting the rate of (BBH) coalescences inferred from 16 days of coincident Advanced LIGO observations surrounding the transient (GW) signal GW150914. In that work we reported various rate estimates whose 90% confidence intervals fell in the range 2–600 Gpc−3 yr−1. Here we give details on our method and computations, including information about our search pipelines, a derivation of our likelihood function for the analysis, a description of the astrophysical search trigger distribution expected from merging BBHs, details on our computational methods, a description of the effects and our model for calibration uncertainty, …

Directly Comparing Handoff Protocols For Pediatric Hospitalists, Elizabeth H. Lazzara, Robert Riss, Brady Patzer, Dustin C. Smith, Y. Raymond Chan, Joseph R. Keebler, Sarah D. Fouquet, Evan M. Palmer

Publications

BACKGROUND AND OBJECTIVES: Handoff protocols are often developed by brainstorming and consensus, and few are directly compared. We hypothesized that a handoff protocol (Flex 11) developed using a rigorous methodology would be more favorable in terms of clinicians’ attitudes, behaviors, cognitions, or time-on-task when performing handoffs compared with a prevalent protocol (Situation Background Assessment Recommendation [SBAR]).

METHODS: Using a between-groups, randomized control trial design (Flex 11 versus SBAR) during a pilot study in a simulated environment, 20 clinicians (13 attending physicians and 7 residents) received 3 patient handoffs from a standardized physician, managed the patients, and handed off the patients …

Worldwide Trends In Blood Pressure From 1975 To 2015: A Pooled Analysis Of 1479 Population-Based Measurement Studies With 19·1 Million Participants, Bin Zhou, James Bentham, Mariachiara Di Cesare, Honor Bixby, Goodarz Danaei, Melanie J. Cowan, Christopher J. Paciorek, Gitanjali Singh, Kaveh Hajifathalian, James E. Bennett, Cristina Taddei, Con Burns, Tara Coppinger, Ver Bilano, Rodrigo M. Carrillo-Larco, Shirin Djalalinia, Shahab Khatibzadeh, Charles Lugero, Niloofar Peykari, Wan Zhu Zhang, Yuan Lu, Gretchen A. Stevens, Leanne M. Riley, Pascal Bovet, Paul Elliott, Dongfeng Gu, Nayu Ikeda, Rod T. Jackson, Michel Joffres, Andre Pascal Kengne, Tiina Laatikainen, Tai Hing Lam, Avula Laxmaiah, Jing Liu

Publications

Background Raised blood pressure is an important risk factor for cardiovascular diseases and chronic kidney disease. We estimated worldwide trends in mean systolic and mean diastolic blood pressure, and the prevalence of, and number of people with, raised blood pressure, defined as systolic blood pressure of 140 mm Hg or higher or diastolic blood pressure of 90 mm Hg or higher. Methods For this analysis, we pooled national, subnational, or community population-based studies that had measured blood pressure in adults aged 18 years and older. We used a Bayesian hierarchical model to estimate trends from 1975 to 2015 in mean …

Results Of The Deepest All-Sky Survey For Continuous Gravitational Waves On Ligo S6 Data Running On The Einstein@Home Volunteer Distributed Computing Project, B. P. Abbott, K. Gill, B. Hughey, M. J. Szczepańczyk, Michele Zanolin, Et Al.

Publications

We report results of a deep all-sky search for periodic gravitational waves from isolated neutron stars in data from the S6 LIGO science run. The search was possible thanks to the computing power provided by the volunteers of the Einstein@Home distributed computing project.

Observation And Modeling Of Gravity Wave Propagation Through Reflection And Critical Layers Above Andes Lidar Observatory At Cerro Pachón, Chile, Bing Cao, Christopher J. Heale, Yafang Guo, Alan Z. Liu, Jonathan B. Snively

Publications

A complex gravity wave event was observed from 04:30 to 08:10 UTC on 16 January 2015 by a narrow-band sodium lidar and an all-sky airglow imager located at Andes Lidar Observatory (ALO) in Cerro Pachón (30.25∘S, 70.73∘W), Chile. The gravity wave packet had a period of 18–35 min and a horizontal wavelength of about 40–50 km. Strong enhancements of the vertical wind perturbation, exceeding10 m s−1, were found at ∼90 km and ∼103 km, consistent with nearly evanescent wave behavior near a reflection layer. A reduction in vertical wavelength was found as the phase speed approached the background wind speed …

Portable Water Purification System, Marc Compere, Yan Tang, Shavin Pinto, Yung Wong

Publications

An ultra-portable water purification system (1). The system (1) can include a pump (22) for pumping water under pressure through the water purification system (1). The system (1) can also include a battery (14) for supplying power to operate the pump (22), a power source (10) for providing power to the battery (14) and the pump (22), and a charge controller (18), electrically connected to the power source (10), battery (14), and pump (22), for regulating power received from the power source (10) and limiting the power provided to the battery (14) to power the pump (22). The water purification …

A Classic Question Revisited In Red-Winged Blackbirds: Disentangling Confounding Hypotheses Surrounding Parental Investment Theory And Nest Defense Intensity, Justin J. Shew, Jorista Van Der Merwe, Eric M. Schauber, Briana K. Tallitsch, Clayton K. Nielsen

Publications

The pattern of increased nest-defense effort over the course of a nesting season could result from 3 distinct (albeit non-exclusive) mechanisms: increased value of offspring to parents with progression towards independence (parental-investment theory), decreased opportunity for renesting (renesting-potential hypothesis), or decreased perceived costs of defense after repeated encounters with human observers (positive-reinforcement hypothesis). To gauge relative empirical support for each of these mechanisms, we disentangle these 3 often-confounded hypotheses using multi-model inference with mixed-model ordinal regression applied to an extensive red-winged blackbird (Agelaius phoeniceus) nesting data set (4,518 monitoring visits to 1,330 nests). Parent aggression was rated on …

Accident Rates, Phase Of Operations, And Injury Severity For Solo Students In Pursuit Of Private Pilot Certification (1994–2013), Douglas Boyd, Peter Dittmer

Publications

Flight training accidents constitute 14% of general aviation accidents. Herein we determined the rates, injury severity, and phase of flight for primary student solo accidents/incidents (mishaps) in Cessna 172 aircraft. Mishaps over the period spanning 1994–2013 were identified from the NTSB database. Student population data were from the FAA. Statistics employed proportion tests, Poisson distribution, and Mann-Whitney tests. Across the study period, 598 mishaps were identified. While the mishap rate increased nearly two-fold between 1994/1997 and 2002/ 2005, a 35% decline was evident thereafter. Nevertheless, no statistical difference in mishap rates was evident between the initial and current periods. Over …

Protecting The Right To Be An American: How Pennsylvanians Perceive Homeland Security, Alexander Siedschlag

Publications

Pennsylvanians mainly see Homeland Security as a comprehensive effort of the federal government to fight terrorism at home and abroad. While it most often has a positive connotation, the multi-faceted mission space of homeland security is widely unknown.

Perceptions Of And Preferences For A Mobile Health Clinic For Underserved Populations, Melinda Gillispie, Catherine Mobley, Lynette M. Gibson, Arelis Moore De Peralta

Publications

Background: Research has established that members of particular demographic groups are inordinately burdened by differential healthcare access. Mobile health clinics (MHCs) are emerging across health systems to improve access to care of marginalized populations. This study explored the perceptions and concerns of community residents living in underserved neighborhoods toward MHC services.

Methods: This study used a qualitative descriptive design with 5 focus group meetings. Purposive sampling was used to recruit ethnically diverse, English- and Spanish-speaking men and women ages 20–67 residing in 5 underserved neighborhoods in Greenville County, SC.

Results: Participants (N = 35) felt positive about obtaining personalized health …

Prediction Of Defect Propensity For The Manual Assembly Of Automotive Electrical Connectors, Matthew Krugh, Kavit Antani, Laine Mears, Jörg Schulte

Publications

Assembly for automotive production represents a significant proportion of total manufacturing cost, manufacturing time, and overall product cost. Humans remain a cost effective solution to adapt to the requirements of increasing product complexity and variety present in today's flexible manufacturing systems. The human element present in the manufacturing system necessitates a better understanding of the human role in manufacturing complexity. Presented herein is a framework for enumerating assembly variables correlated with the potential for quality defect, presented in the design, process, and human factors domain. A case study is offered that illustrates on a manual assembly process the effect that …

Cutting Force Investigation Of Trochoidal Milling In Nickel-Based Superalloy, Abram Pleta, Laine Mears

Publications

The gas turbine, aerospace and nuclear industries are dependent upon nickel-based superalloys to enable these industries to continue to innovate. Without these materials the industries would fail to achieve new heights of efficiency as the strength and operating temperature requirements continue to climb. Nickel-based superalloys thrive in these elevated temperature applications, where their great resistance to creep and corrosion is coupled with remarkably high strength values. These same characteristics that are invaluable to the final operating environment severely degrade their machinability with high cutting forces and aggressive rate of tool wear.

Cutting Force Investigation Of Trochoidal Milling In Nickel-Based Superalloy, Abram Pleta, Laine Mears

Publications

The gas turbine, aerospace and nuclear industries are dependent upon nickel-based superalloys to enable these industries to continue to innovate. Without these materials the industries would fail to achieve new heights of efficiency as the strength and operating temperature requirements continue to climb. Nickel-based superalloys thrive in these elevated temperature applications, where their great resistance to creep and corrosion is coupled with remarkably high strength values. These same characteristics that are invaluable to the final operating environment severely degrade their machinability with high cutting forces and aggressive rate of tool wear.

Although the field of machining research is very well …

Implications Of Social Support As A Self-Control Resource, June J. Pilcher, Stewart A. Bryant

Publications

Self-control is an intricate component of decision making and effectively managing day-to-day life. Failing to maintain adequate self-control can have negative effects on many desired goals and social experiences. As such, understanding how different facets of the human experience may affect self-control is an important undertaking. One area that is yet unclear is the possible relationships between social support and self-control. Research suggests that social support can be an effective resource in reducing stress and promoting health and well-being. Research has also indicated that stress can be a limiting factor on self-control. In contrast, few studies have focused on social …

Characterizing Teaching Assistants’ Knowledge And Beliefs Following Professional Development Activities Within An Inquiry-Based General Chemistry Context, Lindsay B. Wheeler, Jennifer L. Maeng, Brooke A. Whitworth

Publications

The purpose of this investigation was to explore changes in undergraduate and graduate teaching assistants’ (TAs’) content knowledge and beliefs about teaching within the context of an inquiry-based laboratory course. TAs received professional development (PD), which was informed by the TA training literature base and was designed for TAs implementing a guided inquiry approach to general chemistry laboratory instruction. TAs engaged in ∼20 h of presemester PD and ∼30 h of weekly follow-up PD during the semester. The study utilized a multiple-methods approach within a social constructivist framework to assess changes in the TAs. Participants included eight graduate TAs and …

Synchrony In A Boolean Network Of The L-Arabinose Operon In Escherichia Coli, Andy Jenkins, Matthew Macauley

Publications

The lactose operon in Escherichia coli was the first known gene regulatory network, and it is frequently used as a prototype for new modeling paradigms. Historically, many of these modeling frameworks use differential equations. More recently, Stigler and Veliz-Cuba proposed a Boolean network model that captures the bistability of the system and all of the biological steady states. In this paper, we model the well-known arabinose operon in E. coli with a Boolean network. This has several complex features not found in the lac operon, such as a protein that is both an activator and repressor, a DNA looping mechanism …

Approximate Time To Steady-State Resting Energy Expenditure Using Indirect Calorimetry In Young, Healthy Adults, Collin J. Popp, Jocelyn J. Tisch, Kenan E. Sakarcan, William C. Bridges, Elliot D. Jesch

Publications

Indirect calorimetry (IC) measurements to estimate resting energy expenditure (REE) necessitate a stable measurement period or steady state (SS). There is limited evidence when assessing the time to reach SS in young, healthy adults. The aims of this prospective study are to determine the approximate time to necessary reach SS using open-circuit IC and to establish the appropriate duration of SS needed to estimate REE. One hundred young, healthy participants (54 males and 46 females; age = 20.6 ± 2.1 years; body weight = 73.6 ± 16.3 kg; height 172.5 ± 9.3 cm; BMI = 24.5 ± 3.8 kg/m^{2 …}

The Digital “Lure”: Small Businesses And Pokémon Go, Jordan Frith

Publications

Most of the discussion about Pokémon Go has focused on the end-user and the playful nature of the game. Experts have mentioned the game’s commercialism, but they have done so mostly by talking about the data collection practices of the app developers. This commentary piece takes a different approach by examining how businesses have used Pokémon Go’s “lures” to attract foot traffic. The main goal of the article is to show how the ludic, digital wayfaring of location-based games can be used by individual places to attract players. While the focus is on business owners, I will also address …

Pennsylvania 2016 Pre-Election Poll On Policy And Governance, Alexander Siedschlag

Publications

Pennsylvanians mainly see Homeland Security as a comprehensive effort of the federal government to fight terrorism at home and abroad. While it most often has a positive connotation, the multi-faceted mission space of homeland security is widely unknown.