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Full-Text Articles in Physical Sciences and Mathematics

Disturbance Interactions In Subalpine Forests, Their Impacts On Forest Resilience, Carbon, And Future Carbon Storage Under A Variety Of Management And Climate Change Scenarios, Brian Buma Jan 2913

Disturbance Interactions In Subalpine Forests, Their Impacts On Forest Resilience, Carbon, And Future Carbon Storage Under A Variety Of Management And Climate Change Scenarios, Brian Buma

Ecology & Evolutionary Biology Graduate Theses & Dissertations

Forest disturbances are inevitable, and recovery from those disturbances (termed resilience) is required for the persistence of forests through time. Extraordinarily severe or compounding multiple disturbances may, however, exceed that resilience and shift the ecosystems into alternate regimes with potentially large implications for ecosystem structure and functioning. A compound disturbance event (wind, logging, and fire) in a Colorado subalpine forest was studied for the impact of the multiple disturbance events on disturbance characteristics, tree regeneration, and carbon stocks, an important ecosystem service provided by many forests. The regeneration was also grown using the Forest Vegetation Simulator to simulate the effects ...


Real Analysis I, Ismail Nikoufar Dec 2105

Real Analysis I, Ismail Nikoufar

Ismail Nikoufar

Real Analysis slides for my graduate students.


Effect Of Head Group Size On The Photoswitching Applications Of Azobenzene Disperse Red 1 Analogues, Chris Corkery, Alexis Goulet-Hanssens, Arri Priimagi, Christopher Barrett Dec 2103

Effect Of Head Group Size On The Photoswitching Applications Of Azobenzene Disperse Red 1 Analogues, Chris Corkery, Alexis Goulet-Hanssens, Arri Priimagi, Christopher Barrett

Chris Corkery

No abstract provided.


Analysis Of Nonequilibrium Hcp Precipitate Growth In Fcc Matrices: Application To Al–Ag, Daniel Finkenstadt, Duane Johnson Nov 2029

Analysis Of Nonequilibrium Hcp Precipitate Growth In Fcc Matrices: Application To Al–Ag, Daniel Finkenstadt, Duane Johnson

Duane D. Johnson

Hexagonal-close-packed (hcp) γ-precipitates with large aspect ratios form rapidly in some face-centered cubic (fcc) solid-solutions. No model explains the observed time-dependent increase in aspect ratio, nor irregular intermediate growth shapes. We propose a nonequilibrium process involving trapezoidal offshoots (controlled only by energetics) that governs the growth behavior (kinetics) and yields nonequilibrium structures in agreement with observation. Then, combining nucleation theory and diffusion-limited growth both of secondary nuclei and ledges, we derive a general growth equation for γ-precipitates due to solute-segregation to precipitate–matrix interfaces that includes our modification of the Jones–Trivedi model for thickening to account for the slow ...


Roman Domination In Complementary Prisms, Alawi I. Alhashim May 2017

Roman Domination In Complementary Prisms, Alawi I. Alhashim

Electronic Theses and Dissertations

The complementary prism GG of a graph G is formed from the disjoint union of G and its complement G by adding the edges of a perfect match- ing between the corresponding vertices of G and G. A Roman dominating function on a graph G = (V,E) is a labeling f : V(G) → {0,1,2} such that every vertex with label 0 is adjacent to a vertex with label 2. The Roman domination number γR(G) of G is the minimum f(V ) = Σv∈V f(v) over all such functions of G. We study the Roman domination number ...


Synthesis And In-Vitro Cell Viability/Cytotoxicity Studies Of Novel Pyrrolobenzodiazepine Derivatives, John M. Jarrett May 2017

Synthesis And In-Vitro Cell Viability/Cytotoxicity Studies Of Novel Pyrrolobenzodiazepine Derivatives, John M. Jarrett

Undergraduate Honors Theses

Pyrrolobenzodiazepines (PBDs) are a group of naturally occurring compounds that were discovered in the cultures of Streptomyces in the 1960s. Some natural PBDs discovered in these cultures, such as anthramycin and sibiromycin, were shown to possess a broad spectrum of anti-tumor activity. Since cancer is still a leading cause of death globally, the development of novel anti-proliferative derivatives of PBDs is essential for human welfare worldwide. Further synthesis and structure-activity relationship (SAR) studies of the parent natural products and their tetracyclic analogs will lead to the discovery of drug candidates. In this work, thirteen PBD analogues were synthesized using no ...


Sustainability Education In Primary And Secondary Schools: Great Needs And Possible Solutions, Allison Watson May 2017

Sustainability Education In Primary And Secondary Schools: Great Needs And Possible Solutions, Allison Watson

University of Tennessee Honors Thesis Projects

No abstract provided.


Implementing Propensity Score Matching With Network Data: The Effect Of Gatt On Bilateral Trade, Luca De Benedictis, Bruno Arpino, Alessandra Mattei Mar 2017

Implementing Propensity Score Matching With Network Data: The Effect Of Gatt On Bilateral Trade, Luca De Benedictis, Bruno Arpino, Alessandra Mattei

Luca De Benedictis

Motivated by the evaluation of the causal effect of the General Agreement on Tariffs and Trade on bilateral international trade flows, we investigate the role of network structure in propensity score matching under the assumption of strong ignorability. We study the sensitivity of causal inference with respect to the presence of characteristics of the network in the set of confounders conditional on which strong ignorability is assumed to hold. We find that estimates of the average causal effect are highly sensitive to the presence of node-level network statistics in the set of confounders. Therefore, we argue that estimates may suffer ...


Session A-3: Three-Act Math Tasks, Lindsey Herlehy Mar 2017

Session A-3: Three-Act Math Tasks, Lindsey Herlehy

Professional Learning Day

Participants will engage in a Three-Act Math task highlighting the application of properties of geometrical figures. Developed by Dan Meyer, an innovative and highly regarded mathematics instructor, Three-Act Math tasks utilize pedagogical skills that elicit student curiosity, collaboration and questioning. By posing a mathematical problem through active storytelling, this instructional approach redefines real-world mathematics and clarifies the role that a student plays in the learning process. Participants will be given multiple resources where they can access Three-Act Math tasks appropriate for upper elementary grades through Algebra and Geometry courses.


Mixed-Initiative Personal Assistants, Joshua W. Buck Mar 2017

Mixed-Initiative Personal Assistants, Joshua W. Buck

Computer Science Faculty Publications

Specification and implementation of flexible human-computer dialogs is challenging because of the complexity involved in rendering the dialog responsive to a vast number of varied paths through which users might desire to complete the dialog. To address this problem, we developed a toolkit for modeling and implementing task-based, mixed-initiative dialogs based on metaphors from lambda calculus. Our toolkit can automatically operationalize a dialog that involves multiple prompts and/or sub-dialogs, given a high-level dialog specification of it. Our current research entails incorporating the use of natural language to make the flexibility in communicating user utterances commensurate with that in dialog ...


Rate And Apparent Quantum Yield Of Photodissolution, Meg Estapa, Lawrence M. Mayer, Emmanuel Boss Jan 2017

Rate And Apparent Quantum Yield Of Photodissolution, Meg Estapa, Lawrence M. Mayer, Emmanuel Boss

Meg Estapa

We quantified rates of photochemical dissolution (photodissolution) of organic carbon in coastal Louisiana suspended sediments, conducting experiments under well-defined conditions of irradiance and temperature. Optical properties of the suspended sediments were characterized and used in a radiative transfer model to compute irradiances within turbid suspensions. Photodissolution rate increased with temperature (T), with activation energy of 32 ± 7 kJ mol−1, which implicates indirect (non-photochemical) steps in the net reaction. In most samples, dissolved organic carbon (DOC) concentration increased approximately linearly with time over the first 4 h of irradiation under broadband simulated sunlight, after higher rates in the initial hour ...


Role Of Iron And Organic Carbon In Mass-Specific Light Absorption By Particulate Matter From Louisiana Coastal Waters, Meg Estapa, Emmanuel E. Boss, Mayer M. Lawrence, Roesler S. Collin Jan 2017

Role Of Iron And Organic Carbon In Mass-Specific Light Absorption By Particulate Matter From Louisiana Coastal Waters, Meg Estapa, Emmanuel E. Boss, Mayer M. Lawrence, Roesler S. Collin

Meg Estapa

We investigated the influences of organic content and mineralogical composition on light absorption by mostly mineral suspended particles in aquatic and coastal marine systems. Mass-specific absorption spectra of suspended particles and surface sediments from coastal Louisiana and the lower Mississippi and Atchafalaya rivers were measured with a centered sample-mount integrating sphere and analyzed in conjunction with organic carbon (OC), hydrochloric acid– (HCl-) extractable iron, and dithionite-extractable iron contents. Compositions and absorption properties were comparable to published values for similar particles. Dithionite-extractable iron was strongly correlated with absorption at ultraviolet (UV) and blue wavelengths, while OC and HCl-extractable iron were weakly ...


Decoupling Of Net Community Production And Export Production At Submesoscale Fronts In The Sargasso Sea, Meg Estapa, D. A. Siegel, K O. Buesseler, R. H. R. Stanley, M. W. Lomas, N. B. Nelson Jan 2017

Decoupling Of Net Community Production And Export Production At Submesoscale Fronts In The Sargasso Sea, Meg Estapa, D. A. Siegel, K O. Buesseler, R. H. R. Stanley, M. W. Lomas, N. B. Nelson

Meg Estapa

Determinations of the net community production (NCP) in the upper ocean and the particle export production (EP) should balance over long time and large spatial scales. However, recent modeling studies suggest that a horizontal decoupling of flux-regulating processes on submesoscales (≤10 km) could lead to imbalances between individual determinations of NCP and EP. Here we sampled mixed-layer biogeochemical parameters and proxies for NCP and EP during 10, high-spatial resolution (~2 km) surface transects across strong physical gradients in the Sargasso Sea. We observed strong biogeochemical and carbon flux variability in nearly all transects. Spatial coherence among measured biogeochemical parameters within ...


Autonomous, High-Resolution Observations Of Particle Flux In The Oligotrophic Ocean, Meg Estapa, K. Buesseler, E. Boss, G. Gerbi Jan 2017

Autonomous, High-Resolution Observations Of Particle Flux In The Oligotrophic Ocean, Meg Estapa, K. Buesseler, E. Boss, G. Gerbi

Meg Estapa

Observational gaps limit our understanding of particle flux attenuation through the upper mesopelagic because available measurements (sediment traps and radiochemical tracers) have limited temporal resolution, are labor-intensive, and require ship support. Here, we conceptually evaluate an autonomous, optical proxy-based method for high-resolution observations of particle flux. We present four continuous records of particle flux collected with autonomous profiling floats in the western Sargasso Sea and the subtropical North Pacific, as well as one shorter record of depth-resolved particle flux near the Bermuda Atlantic Time-series Study (BATS) and Oceanic Flux Program (OFP) sites. These observations illustrate strong variability in particle flux ...


Particle Dynamics In The Rising Plume At Piccard Hydrothermal Field, Mid-Cayman Rise, Meg Estapa, J. A. Breier, C R. German Jan 2017

Particle Dynamics In The Rising Plume At Piccard Hydrothermal Field, Mid-Cayman Rise, Meg Estapa, J. A. Breier, C R. German

Meg Estapa

Processes active in rising hydrothermal plumes, such as precipitation, particle aggregation, and biological growth, affect particle size distributions and can exert important influences on the biogeochemical impact of submarine venting of iron to the oceans and their sediments. However, observations to date of particle size distribution within these systems are both limited and conflicting. In a novel buoyant hydrothermal plume study at the recently discovered high-temperature (398°C) Piccard Hydrothermal Field, Mid-Cayman Rise, we report optical measurements of particle size distributions (PSDs). We describe the plume PSD in terms of a simple, power-law model commonly used in studies of upper ...


Carbon Flux From Bio-Optical Profiling Floats: Calibrating Transmissometers For Use As Optical Sediment Traps, Meg Estapa, Colleen Durkin, Ken Buesseler, Rod Johnson, Melanie Feena Jan 2017

Carbon Flux From Bio-Optical Profiling Floats: Calibrating Transmissometers For Use As Optical Sediment Traps, Meg Estapa, Colleen Durkin, Ken Buesseler, Rod Johnson, Melanie Feena

Meg Estapa

Our mechanistic understanding of the processes controlling the ocean's biological pump is limited, in part, by our lack of observational data at appropriate timescales. The “optical sediment trap” (OST) technique utilizes a transmissometer on a quasi-Lagrangian platform to collect sedimenting particles. This method could help fill the observational gap by providing autonomous measurements of particulate carbon (PC) flux in the upper mesopelagic ocean at high spatiotemporal resolution. Here, we used a combination of field measurements and laboratory experiments to test hydrodynamic and zooplankton-swimmer effects on the OST method, and we quantitatively calibrated this method against PC flux measured directly ...


Observations Of Carbon Export By Small Sinking Particles In The Upper Mesopelagic, Colleen A. Durkin, Meg Estapa, Ken O. Buesseler Jan 2017

Observations Of Carbon Export By Small Sinking Particles In The Upper Mesopelagic, Colleen A. Durkin, Meg Estapa, Ken O. Buesseler

Meg Estapa

Carbon and nutrients are transported out of the surface ocean and sequestered at depth by sinking particles. Sinking particle sizes span many orders of magnitude and the relative influence of small particles on carbon export compared to large particles has not been resolved. To determine the influence of particle size on carbon export, the flux of both small (11–64 μm) and large (> 64 μm) particles in the upper mesopelagic was examined during 5 cruises of the Bermuda Atlantic Time Series (BATS) in the Sargasso Sea using neutrally buoyant sediment traps mounted with tubes containing polyacrylamide gel layers and tubes ...


Climate And Water Resources In The Carolinas: Approaches To Applying Global Climate Change Information To Local Decisions, Kirsten Lackstrom, Gregory J. Carbone, Daniel L. Tufford, Aashka Patel Jan 2017

Climate And Water Resources In The Carolinas: Approaches To Applying Global Climate Change Information To Local Decisions, Kirsten Lackstrom, Gregory J. Carbone, Daniel L. Tufford, Aashka Patel

Journal of South Carolina Water Resources

A wide range of resource managers, community planners, and other stakeholders are increasingly asking for information regarding how climate change will affect South Carolina’s freshwater and coastal resources. They are interested in using this information for decisions related to infrastructure design, water system planning, vulnerability assessments, and ecosystem management. While climate change data, projections, and related information are also becoming increasingly available, many uncertainties around future climate change and its potential impacts often hinder its application. Furthermore it is often not available in a format or at a scale that is easily translated to local- and regional resource management ...


Adjusting Nrcs Curve Number For Rainfall Durations Less Than 24 Hours, Michael Meadows Jan 2017

Adjusting Nrcs Curve Number For Rainfall Durations Less Than 24 Hours, Michael Meadows

Journal of South Carolina Water Resources

The primary use of the Natural Resources Conservation Service (NRCS) curve number (CN) is to compute total storm runoff based on total rainfall. The method was originally created to determine the mean daily depth of runoff during flood producing events on small agricultural watersheds. CN values were determined using daily rainfall and runoff data. Practically, it did not rain for 24 hours during many, perhaps most, of the events, but since the data were recorded as daily rainfall, 24 hours became the implicit duration for values input to the curve number runoff model. NRCS references do not specifically state the ...


A Policy Lens Of South Carolina Coastal Stormwater Management, Lori A. Dickes, Jeffrey Allen, Monika Jalowiecka, Katie Buckley Jan 2017

A Policy Lens Of South Carolina Coastal Stormwater Management, Lori A. Dickes, Jeffrey Allen, Monika Jalowiecka, Katie Buckley

Journal of South Carolina Water Resources

Similar to many environmental issues today, stormwater management lies within a network of regulatory and policy oversight. As South Carolina coastal communities continue to experience economic and population growth, understanding the broader policy context of stormwater pond management is important. This study was aimed at compiling the state-of-the-knowledge of stormwater pond management policy for the eight coastal counties of South Carolina. In order to enhance researchers and policymakers understanding of the stormwater policy and regulatory environment, this research utilizes a mixed methods approach. A mixed methods approach allows researchers to explore different components of a particular research question by deploying ...


Hydro-Meteorologic Assessment Of October 2015 Extreme Precipitation Event On Santee Experimental Forest Watersheds, South Carolina, Devendra M. Amatya, Charles A. Harrison, Carl C. Trettin Jan 2017

Hydro-Meteorologic Assessment Of October 2015 Extreme Precipitation Event On Santee Experimental Forest Watersheds, South Carolina, Devendra M. Amatya, Charles A. Harrison, Carl C. Trettin

Journal of South Carolina Water Resources

The extreme precipitation event on October 3-4, 2015, likely resulting from the convergence of a persistent deep easterly flow, the continuous supply of moisture, the terrain, and the circulation associated with Hurricane Joaquin off the eastern Atlantic Coast (http://cms.met.psu. edu/sref/severe/2015/04Oct2015.pdf) resulted in extreme and prolonged flooding in many parts of South Carolina. We present the precipitation amounts and intensities observed at four gauges on the USDA Forest Service Santee Experimental Forest (SEF) watersheds during this extreme event in conjunction with the antecedent conditions for 5 days prior to the event. All four ...


Development Of Extended Unimpaired Streamflow Records In The Saluda Basin, South Carolina, C. Alex Pellett, John Boyer, Nina Caraway, Tim Cox, Joseph A. Gellici, Scott Harder, Andy Wachob, Kirk Westphal Jan 2017

Development Of Extended Unimpaired Streamflow Records In The Saluda Basin, South Carolina, C. Alex Pellett, John Boyer, Nina Caraway, Tim Cox, Joseph A. Gellici, Scott Harder, Andy Wachob, Kirk Westphal

Journal of South Carolina Water Resources

This paper presents the steps involved and the methodologies employed in the first phase of the South Carolina Surface Water Assessment - development of extended and unimpaired streamflow estimates based on USGS gage data in the Saluda basin. Streamflow data are first adjusted to remove effects of anthropogenic impairments. Adjustments are made for reservoirs, withdrawals, and discharges based on available documentation. Where documentation is insufficient, hindcasting methods are used. The resulting datasets are called unimpaired flows (UIFs).

The UIFs are then extended in time from 1925, the starting date of the first continuous stream discharge data available in the basin, through ...


The Historic South Carolina Rainfall And Major Floods Of October 1-5, 2015, Hope Mizzell, Mark Malsick, Wes Tyler Jan 2017

The Historic South Carolina Rainfall And Major Floods Of October 1-5, 2015, Hope Mizzell, Mark Malsick, Wes Tyler

Journal of South Carolina Water Resources

A record setting and historic rainfall event occurred October 1-5, 2015, producing widespread and significant flooding across much of South Carolina. The rainfall resulted from several atmospheric and hydrometeorological factors. The record rainfall triggered flash floods and riverine flooding that resulted in emergency evacuations, travel disruptions, personal property damage, business losses, bridge collapses, dam failures and tragic loss of life. Precipitation records were broken from the midlands to the coast, with totals ranging from 10 to over 26 inches of rain. Sixteen National Weather Service Cooperative Weather Stations set new 24-hour rainfall records for October. The amount of rainfall during ...


Journal Of South Carolina Water Resources Volume 3, Issue 1 Jan 2017

Journal Of South Carolina Water Resources Volume 3, Issue 1

Journal of South Carolina Water Resources

It has been a busy and somewhat tumultuous time for South Carolina’s water resources since the publication of the Journal’s second volume. This past October, Hurricane Matthew caused significant flooding and major property damage throughout a large swath from Beaufort County in the Lowcountry up into eastern North Carolina. The small town of Nichols on the Little Pee Dee River in Marion County was especially hard hit. Residents there continue salvage and recovery work, and dozens of properties were lost. Meanwhile, recovery efforts are still ongoing in many areas from the storm complex of October 2015 which created ...


Yale’S Environmental Performance Index: The Construction And Use Of A Composite Index For Global Sustainability, Zach Wendling Jan 2017

Yale’S Environmental Performance Index: The Construction And Use Of A Composite Index For Global Sustainability, Zach Wendling

Yale Day of Data

No abstract provided.


Closing The Water Budget In An Experimental Urban Watershed: A Comparative Assessment Of Methods For Measuring Evapotranspiration, Leana M. Weissberg, Gaboury Benoit Jan 2017

Closing The Water Budget In An Experimental Urban Watershed: A Comparative Assessment Of Methods For Measuring Evapotranspiration, Leana M. Weissberg, Gaboury Benoit

Yale Day of Data

No abstract provided.


Extracting Geography From Datasets In Social Sciences, Yuke Li, Tianhao Wu, Nicholas Marshall, Stefan Steinerberger Jan 2017

Extracting Geography From Datasets In Social Sciences, Yuke Li, Tianhao Wu, Nicholas Marshall, Stefan Steinerberger

Yale Day of Data

No abstract provided.


Safer Chemicals Design Diagrams, Longzhu Shen, Fjodor Melnikov, John Roethle, Aditya Gudibanda, Richard Judson, Julie Zimmerman, Paul Anastas Jan 2017

Safer Chemicals Design Diagrams, Longzhu Shen, Fjodor Melnikov, John Roethle, Aditya Gudibanda, Richard Judson, Julie Zimmerman, Paul Anastas

Yale Day of Data

The NRF2-ARE antioxidant pathway is an important biological sensing and regulating system that responds to chemical insults. At minute level, it protects a living species to go through hard environmental conditions. However, when the external disruption exceeds the inherent resilience, cellular damage can occur, eventually leading to cytotoxicity. Therefore, studying the likelihood of a chemical activating the NRF2-ARE pathway is interesting to discovering therapeutic agents and designing safer chemicals. In this research, we engaged a combination of computational chemistry, statistical learning and mechanistic toxicology to estimate the likelihood of a chemical to perturb this critical toxicological pathway and derive a ...


Data Collection And Analysis At The Atlas Detector, Savannah Thais Jan 2017

Data Collection And Analysis At The Atlas Detector, Savannah Thais

Yale Day of Data

No abstract provided.


Steady State Probabilities In Relation To Eigenvalues, Pellegrino Christopher Jan 2017

Steady State Probabilities In Relation To Eigenvalues, Pellegrino Christopher

The Kabod

By using the methods of Hamdy Taha, eigenvectors can be used in solving problems to compute steady state probabilities, and they work every time.