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Articles 145291 - 145320 of 302474

Full-Text Articles in Physical Sciences and Mathematics

Studies Of Electrical And Thermal Conductivities Of Sheared Multi-Walled Carbon Nanotube With Isotactic Polypropylene Polymer Composites, Parvathalu Kalakonda, Yanial Cabrera, Robert Judith, Georgi Yordanov Georgiev, Peggy Cebe, Germano S. Iannacchione Jan 2015

Studies Of Electrical And Thermal Conductivities Of Sheared Multi-Walled Carbon Nanotube With Isotactic Polypropylene Polymer Composites, Parvathalu Kalakonda, Yanial Cabrera, Robert Judith, Georgi Yordanov Georgiev, Peggy Cebe, Germano S. Iannacchione

Biological and Physical Sciences Department Faculty Works

Polymer nanocomposite materials of higher thermal and electrical transport properties are important to nanotechnology applications such as thermal management, packaging, labelling and the textile industry. In this work, thermal and electrical conductivities in nanocomposites of multiwalled carbon nanotubes (MWCNT) and isotactic polypropylene (iPP) are investigated in terms of MWCNT loading, temperature dependence, and anisotropy caused by melt shearing. IPP/MWCNT nanocomposites show a significant increase in thermal and electrical conductivity with increasing MWCNT loading, reaching 17.5 W/m K and 10−6 S/m, respectively, at a MWCNT 5.0 weight percentage at 40°C. The increase in MWCNT/iPP is more than would be expected …


Developing And Verifying A Set Of Principles For The Cyber Security Of The Critical Infrastructures Of Turkey, Bilge Karabacak Jan 2015

Developing And Verifying A Set Of Principles For The Cyber Security Of The Critical Infrastructures Of Turkey, Bilge Karabacak

All Faculty and Staff Scholarship

Critical infrastructures are vital assets for countries as a harm given to critical infrastructures may affect public order, economic welfare and/or national security. Today, cyber systems are extensively used to control and monitor critical infrastructures. Therefore, cyber threats have the potential to adversely affect the order of societies and countries. In this PhD study, the root causes of the susceptibility of the critical infrastructures of Turkey to the cyber threats are identified by analyzing the qualitative data with the grounded theory method. The extracted root causes are verified by two experts. The set of principles for the cyber security of …


A Laurentian Margin Back-Arc: The Ordovician Wedowee-Emuckfaw-Dahlonega Basin, Clinton Barineau Jan 2015

A Laurentian Margin Back-Arc: The Ordovician Wedowee-Emuckfaw-Dahlonega Basin, Clinton Barineau

Faculty Bibliography

Independent researchers working in the Talladega belt, Ashland-WedoweeEmuckfaw belt, and Opelika Complex of Alabama, as well as the Dahlonega gold belt and western Inner Piedmont of Alabama, Georgia, and the Carolinas, have mapped stratigraphic sequences unique to each region. Although historically considered distinct terranes of disparate origin, a synthesis of data suggests that each includes lithologic units that formed in an Ordovician back-arc basin (Wedowee-EmuckfawDahlonega basin—WEDB). Rocks in these terranes include varying proportions of metamorphosed mafi c and bimodal volcanic rock suites interlayered with deep-water metasedimentary rock sequences. Metavolcanic rocks yield ages that are Early– Middle Ordovician (480–460 Ma) and …


Using Regression Tools To Assess Hazard Identification In The U.S. Army Risk Management Process, Rania Hodhod, Heath L. Mccormick Jan 2015

Using Regression Tools To Assess Hazard Identification In The U.S. Army Risk Management Process, Rania Hodhod, Heath L. Mccormick

Faculty Bibliography

This research considers whether a person‟s demographic and experiential attributes play a significant role in how they perceive the presence or absence of hazards in a given situation. The goal of the research is to show that participants with enlisted military experience, prior to being commissioned as a junior officer, would be more successful at identifying the hazards presented in military scenarios than those who had only been trained on the process via their pre-commissioning and initial entry courses of instruction. The research study involves the use of two surveys with realistic military scenarios including both Foot March and Maintenance …


Hfq Regulates Antibacterial Antibiotic Biosynthesis And Extracellular Lytic-Enzyme Production In Lysobacter Enzymogenes Oh11, Gaoge Xu, Yuxin Zhao, Liangcheng Du, Guoliang Qian, Fengquan Liu Jan 2015

Hfq Regulates Antibacterial Antibiotic Biosynthesis And Extracellular Lytic-Enzyme Production In Lysobacter Enzymogenes Oh11, Gaoge Xu, Yuxin Zhao, Liangcheng Du, Guoliang Qian, Fengquan Liu

Chemistry Department: Faculty Publications

Lysobacter enzymogenes is an important biocontrol agent with the ability to produce a variety of lytic enzymes and novel antibiotics. Little is known about their regulatory mechanisms. Understanding these will be helpful for improving biocontrol of crop diseases and potential medical application. In the present study, we generated an hfq (encoding a putative ribonucleic acid chaperone) deletion mutant, and then utilized a new genomic marker-free method to construct an hfq-complemented strain. We showed for the first time that Hfq played a pleiotropic role in regulating the antibacterial antibiotic bio- synthesis and extracellular lytic enzyme activity in L. enzymogenes. Mutation of …


Biotechnological Production Of 1,2,4-Butanetriol: An Efficient Process To Synthesize Energetic Material Precursor From Renewable Biomass, Yujin Cao, Wei Niu, Jiantao Guo, Mo Xian, Huizhou Liu Jan 2015

Biotechnological Production Of 1,2,4-Butanetriol: An Efficient Process To Synthesize Energetic Material Precursor From Renewable Biomass, Yujin Cao, Wei Niu, Jiantao Guo, Mo Xian, Huizhou Liu

Chemistry Department: Faculty Publications

1,2,4-Butanetriol (BT) is a valuable chemical with extensive applications in many different fields. The traditional chemical routes to synthesize BT suffer from many drawbacks, e.g., harsh reaction conditions, multiple steps and poor selectivity, limiting its industrial production. In this study, an engineered Escherichia coli strain was constructed to produce BT from xylose, which is a major component of the lignocellulosic biomass. Through the coexpression of a xylose dehydrogenase (CCxylB) and a xylonolactonase (xylC) from Caulobacter crescentus, native E. coli xylonate dehydratase (yjhG), a 2-keto acid decarboxylase from Pseudomonas putida (mdlC) and …


Recyclable Magnetite Nanoparticle Catalyst For One-Pot Conversion Of Cellobiose To 5-Hydroxymethylfurfural In Water, Anuja Bhalkikar, Zane C. Gernhart, Chin Li Cheung Jan 2015

Recyclable Magnetite Nanoparticle Catalyst For One-Pot Conversion Of Cellobiose To 5-Hydroxymethylfurfural In Water, Anuja Bhalkikar, Zane C. Gernhart, Chin Li Cheung

Chemistry Department: Faculty Publications

Environmentally benign and easily recoverable magnetite nanoparticles (Fe3O4 NPs) were demonstrated to catalyze the one-pot conversion of cellobiose, a glucose disaccharide, to 5-hydroxymethylfurfural (5-HMF).Theconversion was achieved in water under hydrothermal conditions.The catalytic activity of Fe3O4 NPs surpassed those of iron (II) and iron (III) chlorides in this reaction. Optimized cellobiose conversion reactions catalyzed with Fe3O4 NPs gave the highest 5-HMF yields of 23.4 ± 0.6% at 160C for 24 hours. After three reuses, the Fe3O4 NP catalyst retained its catalytic activity with similar 5-HMF yields, demonstrating …


Unit Origami: Star-Building On Deltahedra, Heidi Burgiel Jan 2015

Unit Origami: Star-Building On Deltahedra, Heidi Burgiel

Mathematics Faculty Publications

This workshop provides instructions for folding the star-building unit – a modification of the Sonobe module for unit origami. Geometric questions naturally arise during this process, ranging in difficulty from middle school to graduate levels. Participants will learn to fold and assemble star-building units, then explore the structure of the eight strictly convex deltahedra.


Letters To Joel, David J. Stucki, Joel M. Stucki Jan 2015

Letters To Joel, David J. Stucki, Joel M. Stucki

Mathematics Faculty Scholarship

A professor and his students answer his brother’s question: Is mathematics art?


Discontinuous Element Insertion Algorithm, Timothy James Truster Jan 2015

Discontinuous Element Insertion Algorithm, Timothy James Truster

Faculty Publications and Other Works -- Civil & Environmental Engineering

An algorithm is presented for inserting zero-thickness interface elements, termed herein as “couplers”, into continuous finite element meshes in two and three dimensions. Insertion is governed solely by the mesh topology and is specified according to regions or subdomains within the overall analysis domain, a geometrically intuitive means to designate the coupler locations. The algorithm is self-contained and requires only nodal coordinates and element connectivity as input. A wide class of volume elements and interface couplers are treated within the framework. Since the algorithm is topologically-based, interfaces of arbitrary complexity are naturally accommodated. Separate treatment is given to inserting couplers …


Finding Aid To The Bern Porter Collection Of Contemporary Letters, Bern Porter, Colby College Special Collections Jan 2015

Finding Aid To The Bern Porter Collection Of Contemporary Letters, Bern Porter, Colby College Special Collections

Finding Aids

Bern Porter (1911–2004) was an artist, writer, philosopher, and scientist who was involved in the development of the cathode ray tube, the Saturn V rocket, and the Manhattan Project, which he renounced upon learning of the bombing of Hiroshima. Also a pioneer in the arts, he is known for his landmark work as an author and publisher. He was an early practitioner of mail art and found and performance poetry and experimented with typography, sculpture, photography, artists’ books, and collage throughout his life. Porter lived and worked in New Jersey, New York, Tennessee, California, Guam, Alabama, and Tasmania. He finally …


Rooted In Soil, Laura Fatemi, Farrah Fatemi, Liam Heneghan Jan 2015

Rooted In Soil, Laura Fatemi, Farrah Fatemi, Liam Heneghan

DePaul Art Museum Publications

No abstract provided.


The ‘New’ Heidegger, Babette Babich Jan 2015

The ‘New’ Heidegger, Babette Babich

Articles and Chapters in Academic Book Collections

If discussion of “new” approaches to Martin Heidegger contradicts Heidegger’s own indictment of the passion for “novelty” in philosophy, today’s Black Notebooks scandal reminds us of the ontic problem of new news. Indeed the backwards working evidence of the notebooks kept before, during, and after WWII both vindicates and problematizes his notion of temporality temporalizing from the future -- lapsing into the past -- setting up what is now regarded as patent in the present. Simultaneously, we see that if heretofore many philosophers of technology sought to dismiss engagement with Heidegger’s critique of technology, these critical contributions turn out to …


Evaluating The Assessment Methodology For The Chlorophyll-A And Secchi Transparency Criteria At Beaver Lake, Arkansas, J. Thad Scott, Brian E. Haggard Jan 2015

Evaluating The Assessment Methodology For The Chlorophyll-A And Secchi Transparency Criteria At Beaver Lake, Arkansas, J. Thad Scott, Brian E. Haggard

Technical Reports

No abstract provided.


The Van Der Waals Equation As A Cubic, Carl W. David Jan 2015

The Van Der Waals Equation As A Cubic, Carl W. David

Chemistry Education Materials

The van der Waals (from his thesis of 1873) equation is a cubic in the molar volume. Since this is the first equation of state studied in chemistry more complicated than the ideal gas equation, it is noteworthy that the solution of this cubic is rarely if ever addressed. When (lowering the temperature) the two imaginary roots coalesce with the real root of the van der Waals equation we have the critical point. At Kelvin temperatures below Tc. the equation has three real roots; we explore obtaining those roots to aid in the Maxwell construction required to obtain the vapor …


Characterization Of Calbindin Positive Interneurons Within The Ventral Horn Of The Mouse Spinal Cord, Taylor L. Floyd, David R. Ladle Jan 2015

Characterization Of Calbindin Positive Interneurons Within The Ventral Horn Of The Mouse Spinal Cord, Taylor L. Floyd, David R. Ladle

Symposium of Student Research, Scholarship, and Creative Activities Materials

Sensory-motor circuits in the spinal cord integrate sensory feedback from muscles and modulate locomotor behavior. Although we know how the sensory-motor system generally works, the main issue lies in identifying all neurons involved and understanding their interrelationships. Many interneurons contribute to sensory-motor circuits and have been well studied. For example, Renshaw cells (RC) are inhibitory interneurons that prevent motor neurons from over-activity. A distinguishing feature of RCs is that they are the only interneurons within the ventral-most region of the spinal cord expressing the calcium binding protein calbindin (CB). Recent studies have found other subpopulations of ventral horn interneurons outside …


2015 Gloucester Point Station Tide Prediction Calendars, Virginia Institute Of Marine Science, David A. Evans Jan 2015

2015 Gloucester Point Station Tide Prediction Calendars, Virginia Institute Of Marine Science, David A. Evans

Miscellaneous

These calendars are produced monthly using David Evans' Tidecal.


2015 Wachapreague Station Tide Prediction Calendars, Virginia Institute Of Marine Science, David A. Evans Jan 2015

2015 Wachapreague Station Tide Prediction Calendars, Virginia Institute Of Marine Science, David A. Evans

Miscellaneous

These calendars are produced monthly using David Evans' Tidecal.


The Environmental Effects Of Coal Fires, Trent Garrison Jan 2015

The Environmental Effects Of Coal Fires, Trent Garrison

Theses and Dissertations--Earth and Environmental Sciences

There are thousands of subterranean coal fires in the world that, because of incomplete combustion, emit a wide variety of volatile and semivolatile organic compounds to the atmosphere, water, and soil at concentrations that could pose health risks to humans and wildlife. The main goals of this study were to (1) review methods that are used to characterize physical and chemical characteristics of coal-fire sites, (2) determine relationships between gas emissions and physical and chemical characteristics of coal-fire sites, using a combination of regression and multivariate statistical methods, and (3) determine the concentrations of volatile and semivolatile organic compounds in …


Math In The Modern World, Steven Cosares Jan 2015

Math In The Modern World, Steven Cosares

Open Educational Resources

Students are asked to gather nutrition data regarding their favorite snacks and assess how well they contribute to their maintenance of a “healthy” diet, as defined through, articles, websites, and guidelines established by the US Department of Agriculture.


Gis Data: City Of Newport News, Virginia Shoreline Management Model, Marcia Berman, Karinna Nunez, Sharon Killeen, Tamia Rudnicky, Julie G. Bradshaw, Karen Duhring, Kory Angstadt, Alexandra Procopi, David Weiss, Carl Hershner Jan 2015

Gis Data: City Of Newport News, Virginia Shoreline Management Model, Marcia Berman, Karinna Nunez, Sharon Killeen, Tamia Rudnicky, Julie G. Bradshaw, Karen Duhring, Kory Angstadt, Alexandra Procopi, David Weiss, Carl Hershner

Data

The Shoreline Management Model is a GIS spatial model that determines appropriate shoreline best management practices using available spatial data and decision tree logic. Available shoreline conditions used in the model include the presence or absence of tidal marshes, beaches, and forested riparian buffers, bank vegetation cover, bank height, wave exposure (fetch), nearshore water depth, and proximity of coastal development to the shoreline. The model output for shoreline best management practices is displayed in the locality Comprehensive Map Viewer. One GIS shapefile is developed that describes two arcs or lines representing practices in the upland area and practices at the …


Configurationally Stable, Enantioenriched Organometallic Nucleophiles In Stereospecific Pd-Catalyzed Cross-Coupling Reactions: An Alternative Approach To Asymmetric Synthesis, Chao-Yuan Wang, Joseph Derosa, Mark R. Biscoe Jan 2015

Configurationally Stable, Enantioenriched Organometallic Nucleophiles In Stereospecific Pd-Catalyzed Cross-Coupling Reactions: An Alternative Approach To Asymmetric Synthesis, Chao-Yuan Wang, Joseph Derosa, Mark R. Biscoe

Publications and Research

Several research groups have recently developed methods to employ configurationally stable, enantioenriched organometallic nucleophiles in stereospecific Pd-catalyzed cross-coupling reactions. By establishing the absolute configuration of a chiral alkyltin or alkylboron nucleophile prior to its use in cross-coupling reactions, new stereogenic centers may be rapidly and reliably generated with preservation of the known initial stereochemistry. While this area of research is still in its infancy, such stereospecific cross-coupling reactions may emerge as simple, general methods to access diverse, optically active products from common enantioenriched organometallic building blocks. This minireview highlights recent progress towards the development of general, stereospecific Pd-catalyzed crosscoupling reactions …


Toxins In Newtown Creek, Burl Yearwood, Cho Cho Aung, Ridima Pradhan, Jennifer Vance Jan 2015

Toxins In Newtown Creek, Burl Yearwood, Cho Cho Aung, Ridima Pradhan, Jennifer Vance

Publications and Research

Newtown Creek is a 3.5 mile river which empties into the East River in New York, United States. The river runs the boundary between the Queens and Brooklyn Burroughs. A thriving sight of industry, this river has been the location of much pollution for over a century. Battered by oil spills and oil seepage, raw sewage, trash carried by rain water, cement, animal fat, and a 15 meter sludge on the bottom of the riverbed, Newtown Creek is one of the most polluted waterways in the United States. In this article, data for nitrate, phosphate, lead, copper, dissolved iron, and …


Geologic, Geotechnical, And Geophysical Investigation Of A Shallow Landslide, Eastern Kentucky, Matthew M. Crawford, Junfeng Zhu, Steven E. Webb Jan 2015

Geologic, Geotechnical, And Geophysical Investigation Of A Shallow Landslide, Eastern Kentucky, Matthew M. Crawford, Junfeng Zhu, Steven E. Webb

Report of Investigations--KGS

In eastern Kentucky, landslides occur in colluvial soils or at the colluvium-bedrock contact, and are commonly triggered by heavy rainfall. These slides occur particularly where steep slopes and weak rocks combine with various methods of slope modification. Landslides can damage roadways, infrastructure, and residences, and mitigation costs can exceed $10 million per year.

The Meadowview landslide in Boyd County was investigated to assess the geologic conditions, extent, and behavior of a rainfall-triggered landslide in eastern Kentucky and evaluate the use of electrical resistivity as a tool to characterize a shallow colluvial landslide. Although this type of landslide is common in …


Summary Of The Kentucky River Watershed Watch 2015 Water Sampling Results, Kentucky Water Resources Research Institute Jan 2015

Summary Of The Kentucky River Watershed Watch 2015 Water Sampling Results, Kentucky Water Resources Research Institute

Kentucky River Watershed Watch

No abstract provided.


Being Smart About Parts, Nathaniel Stevens, S H. Steiner, R J. Mackay Jan 2015

Being Smart About Parts, Nathaniel Stevens, S H. Steiner, R J. Mackay

Mathematics

When conducting a measurement system assessment study, practitioners want as precise an estimate of the true repeatability and reproducibility (R&R) as possible so they can correctly decide whether the measurement system is acceptable. They are, however, faced with cost and time constraints that restrict the number of parts and repeated measurements that can be used in the study. By incorporating freely available production measurements (baseline data), they can reduce the number of parts in the study to two or three and still obtain a better estimate of the R&R than they would have otherwise. To avoid bias, they must ensure …


Ring Patterns And Their Bifurcations In A Nonlocal Model Of Biological Swarms, Andrea L. Bertozzi, T Kolokolnikov, Hui Sun, David Uminsky, J Von Brecht Jan 2015

Ring Patterns And Their Bifurcations In A Nonlocal Model Of Biological Swarms, Andrea L. Bertozzi, T Kolokolnikov, Hui Sun, David Uminsky, J Von Brecht

Mathematics

In this paper we study the pattern formation of a kinematic aggregation model for biological swarming in two dimensions. The swarm is represented by particles and the dynamics are driven by a gradient flow of a non-local interaction potential which has a local repulsion long range attraction structure. We leverage a co-dimension one formulation of the continuum gradient flow to characterize the stability of ring solutions for general interaction kernels. In the regime of long-wave instability we show that the resulting ground state is as a low mode bifurcation away from the ring and use weakly nonlinear analysis to provide …


Assessing Agreement Between Two Measurement Systems: An Alternative To The Limits Of Agreement Approach, Nathaniel Stevens, S H. Steiner, R J. Mackay Jan 2015

Assessing Agreement Between Two Measurement Systems: An Alternative To The Limits Of Agreement Approach, Nathaniel Stevens, S H. Steiner, R J. Mackay

Mathematics

The comparison of two measurement systems is important in medical and other contexts. A common goal is to decide if a new measurement system agrees suitably with an existing one, and hence whether the two can be used interchangeably. Various methods for assessing interchangeability are available, the most popular being the limits of agreement approach due to Bland and Altman. In this article, we review the challenges of this technique and propose a model-based framework for comparing measurement systems that overcomes those challenges. The proposal is based on a simple metric, the probability of agreement, and a corresponding plot which …


An Evaluation-Guided Approach For Effective Data Visualization On Tablets, Peter S. Games, Alark Joshi Jan 2015

An Evaluation-Guided Approach For Effective Data Visualization On Tablets, Peter S. Games, Alark Joshi

Computer Science

There is a rising trend of data analysis and visualization tasks being performed on a tablet device. Apps with interactive data visualization capabilities are available for a wide variety of domains. We investigate whether users grasp how to effectively interpret and interact with visualizations. We conducted a detailed user evaluation to study the abilities of individuals with respect to analyzing data on a tablet through an interactive visualization app. Based upon the results of the user evaluation, we find that most subjects performed well at understanding and interacting with simple visualizations, specifically tables and line charts. A majority of the …


Making Better Fertiliser Decisions For Cropping Systems In Western Australia. Soil Test – Crop Response Relationships And Critical Soil Test Values And Ranges, Geoff Anderson, Ross Brennan, Richard Bell, Wen Chen Jan 2015

Making Better Fertiliser Decisions For Cropping Systems In Western Australia. Soil Test – Crop Response Relationships And Critical Soil Test Values And Ranges, Geoff Anderson, Ross Brennan, Richard Bell, Wen Chen

Bulletins 4000 -

The better fertiliser decisions for cropping project (BFDC) (2009-2012) was completed to provide comprehensive information to improve fertiliser decisions for the cropping industry in Australia (Speirs et al. 2013a). The WA component provides interpretation of results from crop nutrient application experiments for the WA cropping system, and developed a tool for estimating nutrient losses from cropping systems soils.

The BFDC-WA project aims to use the 4R principles by producing a series of bulletins on nutrient management for the cropping system of WA.