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2019

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Articles 301 - 330 of 15926

Full-Text Articles in Physical Sciences and Mathematics

Detection And Inference In Gravitational Wave Astronomy, Steven Daniel Reyes Dec 2019

Detection And Inference In Gravitational Wave Astronomy, Steven Daniel Reyes

Dissertations - ALL

We explore the detection and astrophysical modeling of gravitational waves de- tected by the Advanced Laser Interferometer Gravitational wave Observatory (LIGO) and Virgo. We discuss the techniques used in the PyCBC search pipeline to discover the first gravitational wave detection GW150914, and estimate the statistical signifi- cance of GW150914, and the marginal trigger LVT151012. During Advanced LIGO’s first observing run there were no detections of mergers from binary neutron star and neutron star-black hole binaries. We use Bayesian inference to place upper limits on the rate of coalescence of these binaries. We use developments made in the PyCBC search pipeline …


Strongly Coupled Fermions On The Lattice, Nouman Tariq Butt Dec 2019

Strongly Coupled Fermions On The Lattice, Nouman Tariq Butt

Dissertations - ALL

Since its inception with the pioneering work of Ken Wilson, lattice field theory has come a long way. Lattice formulations have enabled us to probe the non-perturbative structure of theories such as QCD and have also helped in exploring the phase structure and classification of phase transitions in a variety of other strongly coupled theories of interest to both high energy and condensed matter theorists. The lattice approach to QCD has led to an understanding of quark confinement, chiral symmetry breaking and hadronic physics. Correlation functions of hadronic operators and scattering matrix of hadronic states can be calculated in terms …


Diel Temperature And Ph Variability Scale With Depth Across Diverse Coral Reef Habitats, Tyler Cyronak, Yuichiro Takeshita, Travis A. Courtney, Eric H. Decarlo, Bradley D. Eyre, David I. Kline, Todd R. Martz, Heather Page, Nichole Price, Jennifer Smith, Laura Stoltenberg, Martin Tresguerres, Andreas J. Andersson Dec 2019

Diel Temperature And Ph Variability Scale With Depth Across Diverse Coral Reef Habitats, Tyler Cyronak, Yuichiro Takeshita, Travis A. Courtney, Eric H. Decarlo, Bradley D. Eyre, David I. Kline, Todd R. Martz, Heather Page, Nichole Price, Jennifer Smith, Laura Stoltenberg, Martin Tresguerres, Andreas J. Andersson

Marine & Environmental Sciences Faculty Articles

Coral reefs are facing intensifying stressors, largely due to global increases in seawater temperature and decreases in pH. However, there is extensive environmental variability within coral reef ecosystems, which can impact how organisms respond to global trends. We deployed spatial arrays of autonomous sensors across distinct shallow coral reef habitats to determine patterns of spatiotemporal variability in seawater physicochemical parameters. Temperature and pH were positively correlated over the course of a day due to solar heating and light‐driven metabolism. The mean temporal and spatial ranges of temperature and pH were positively correlated across all sites, with different regimes of variability …


Understanding The Role Of Anisotropy On The Optoelectronic And Colloidal Properties Of Quantum Rods For Programmable Self-Assembly With Dna Origami, Yuetian Chen Dec 2019

Understanding The Role Of Anisotropy On The Optoelectronic And Colloidal Properties Of Quantum Rods For Programmable Self-Assembly With Dna Origami, Yuetian Chen

Dissertations - ALL

Semiconductor nanocrystals, like quantum dots (QDs) and quantum rods (QRs), have tunable optoelectronic properties that depend on their composition, size and asymmetry. A small change in size or aspect ratio can lead to measurable changes in optical absorption and photoluminescence emission energies, as well as varied degrees of polarized optical behaviors at those energies. My dissertation research focuses on investigating the role of anisotropy on the optoelectronic and colloidal properties of quantum rods, as well as using DNA-mediated self-assembly to align these quantum rods on DNA origami for energy transfer applications in biocompatible systems. First, CdSe of systematically varied aspect …


Homology Over A Complete Intersection Ring Via The Generic Hypersurface, Eric Jeffrey Ottman Dec 2019

Homology Over A Complete Intersection Ring Via The Generic Hypersurface, Eric Jeffrey Ottman

Dissertations - ALL

We study homological properties and constructions for modules over a complete intersection ring $Q/(f_1,\ldots,f_c)$ by way of the related generic hypersurface ring $Q[T_1,\ldots,T_c]/(f_1T_1+\cdots+f_cT_c)$. The advantage of this approach is that over a hypersurface ring, free resolutions are eventually 2-periodic, given by matrix factorizations, and are thus relatively easy to understand. We approach this relationship in two ways. First, we give a correspondence between the two rings in the graded setting, where existing results are insufficient for preserving graded structures. As an application, we use this correspondence to move a functor appearing in a theorem of Orlov to the generic hypersurface …


Evolution And Stratigraphic Architecture Of Tidal Point Bars With And Without Fluvial Input: Influence Of Variable Flow Regimes On Sediment And Facies Distribution, And Lateral Accretion, Pricilla Souza Dec 2019

Evolution And Stratigraphic Architecture Of Tidal Point Bars With And Without Fluvial Input: Influence Of Variable Flow Regimes On Sediment And Facies Distribution, And Lateral Accretion, Pricilla Souza

University of New Orleans Theses and Dissertations

Tide-influenced point bars represent a significant proportion of shallow-marine deposits, commonly developed along meandering channels in most backbarrier and estuarine systems. However, sedimentological studies to characterize this type of deposit are still emerging. They often present very heterogeneous internal architectures which development is controlled by the complex flow patterns operating in tidal environments. The study of the sedimentological and morphological characteristics of these features provides better understanding of the hydrodynamic processes that shape coastal systems and control their evolution as well as it contributes to better reservoir potential prediction and production strategy optimization, as tidal point bars may represent hydrocarbon …


Computational Studies And Design Of Pparγ And Glut1 Inhibitors, Suliman Almahmoud Dec 2019

Computational Studies And Design Of Pparγ And Glut1 Inhibitors, Suliman Almahmoud

Theses & Dissertations

The peroxisome proliferator-activated receptor gamma (PPARγ) is a ligand-dependent transcription factor of the nuclear receptor superfamily that controls the expression of a variety of genes involved in fatty acid metabolism, adipogenesis, and insulin sensitivity. PPARγ is a target for insulin-sensitizing drugs, and it plays a significant function in prostate cancer. PPARγ antagonists have anti-proliferative effects in a broad range of hematopoietic and epithelial cell lines. The ligand binding domain (LBD) of PPARγ is large and has orthosteric and allosteric binding sites. Several PPARγ-ligand co-crystal structures show two bound molecules, one to the orthosteric pocket and a second to the allosteric …


A Hybrid And Scalable Error Correction Algorithm For Indel And Substitution Errors Of Long Reads, Arghya Kusum Das, Sayan Goswami, Kisung Lee, Seung Jong Park Dec 2019

A Hybrid And Scalable Error Correction Algorithm For Indel And Substitution Errors Of Long Reads, Arghya Kusum Das, Sayan Goswami, Kisung Lee, Seung Jong Park

Computer Science Faculty Research & Creative Works

Background: Long-read sequencing has shown the promises to overcome the short length limitations of second-generation sequencing by providing more complete assembly. However, the computation of the long sequencing reads is challenged by their higher error rates (e.g., 13% vs. 1%) and higher cost ($0.3 vs. $0.03 per Mbp) compared to the short reads. Methods: In this paper, we present a new hybrid error correction tool, called ParLECH (Parallel Long-read Error Correction using Hybrid methodology). The error correction algorithm of ParLECH is distributed in nature and efficiently utilizes the k-mer coverage information of high throughput Illumina short-read sequences to rectify the …


The Effects Of Sediment Acidification And Temperature On The Immune Capacity Of The Atlantic Jackknife (Razor) Clam (Ensis Leei M. Huber, 2015), Brian Preziosi Dec 2019

The Effects Of Sediment Acidification And Temperature On The Immune Capacity Of The Atlantic Jackknife (Razor) Clam (Ensis Leei M. Huber, 2015), Brian Preziosi

Electronic Theses and Dissertations

Sediment acidification has been shown to negatively impact clams of economic importance such as the soft-shell clam, Mya arenaria Linnaeus, 1758, and hard clam, Mercenaria mercenaria (Linnaeus, 1758). Effects of sediment acidification on razor clams, including the Atlantic jackknife clam Ensis leei M. Huber, 2015, are unknown. E. leei has been identified as a species with potential for aquaculture operations on the New England coast. E. leei may be resilient to acidification and thus persist in acidified sediments where other clams cannot. To this end, the impact of acidified surface sediment on the internal immune capacity of adult (mean shell …


Digital Readout And Control Of A Superconducting Qubit, Caleb Jordan Howington Dec 2019

Digital Readout And Control Of A Superconducting Qubit, Caleb Jordan Howington

Dissertations - ALL

In the quest to build a fault-tolerant quantum computer, superconducting circuits based on Josephson junctions have emerged as a leading architecture. Coherence times have increased significantly over the last two decades, and processors with ∼ 50 qubits have been experimentally demonstrated. These systems traditionally utilize microwave frequency control signals, and heterodyne based detection schemes for measurement. Both of these techniques rely heavily on room temperature microwave generators, high-bandwidth lines from room temperature to millikelvin temperatures, and bulky non-reciprocal elements such as cryogenic microwave isolators. Reliance on these elements makes it impractical to scale existing devices up a single order of …


A Voice Interactive Multilingual Student Support System Using Ibm Watson, Kennedy Ralston, Yuhao Chen, Haruna Isah, Farhana Zulkernine Dec 2019

A Voice Interactive Multilingual Student Support System Using Ibm Watson, Kennedy Ralston, Yuhao Chen, Haruna Isah, Farhana Zulkernine

Publications and Scholarship

Systems powered by artificial intelligence are being developed to be more user-friendly by communicating with users in a progressively human-like conversational way. Chatbots, also known as dialogue systems, interactive conversational agents, or virtual agents are an example of such systems used in a wide variety of applications ranging from customer support in the business domain to companionship in the healthcare sector. It is becoming increasingly important to develop chatbots that can best respond to the personalized needs of their users so that they can be as helpful to the user as possible in a real human way. This paper investigates …


The Vezo Communities And Fisheries Of The Coral Reef Ecosystem In The Bay Of Ranobe, Madagascar, Shane Abeare Dec 2019

The Vezo Communities And Fisheries Of The Coral Reef Ecosystem In The Bay Of Ranobe, Madagascar, Shane Abeare

University of New Orleans Theses and Dissertations

Madagascar, a country whose extraordinary levels of endemism and biodiversity are celebrated globally by scientists and laymen alike, yet historically has received surprisingly little research attention, is the setting of the present dissertation. Here, I contribute to the need for applied research by: 1) focusing on the most intensely fished section of the Toliara Barrier Reef, the Bay of Ranobe; 2) characterizing the marine environment, the human population, and the fisheries; and 3) collecting the longest known time-series of data on fisheries of Madagascar, thereby providing a useful baseline for future analyses. In Chapter 1, the bathymetry of the Bay …


A Qualitative Representation Of Spatial Scenes In R2 With Regions And Lines, Joshua Lewis Dec 2019

A Qualitative Representation Of Spatial Scenes In R2 With Regions And Lines, Joshua Lewis

Electronic Theses and Dissertations

Regions and lines are common geographic abstractions for geographic objects. Collections of regions, lines, and other representations of spatial objects form a spatial scene, along with their relations. For instance, the states of Maine and New Hampshire can be represented by a pair of regions and related based on their topological properties. These two states are adjacent (i.e., they meet along their shared boundary), whereas Maine and Florida are not adjacent (i.e., they are disjoint).

A detailed model for qualitatively describing spatial scenes should capture the essential properties of a configuration such that a description of the represented objects …


Evidence For Accelerated Weathering And Sulfate Export In High Alpine Environments, John T. Crawford, Eve-Lyn S. Hinckley, M. Iggy Litaor, Janice Brahney, Jason C. Neff Dec 2019

Evidence For Accelerated Weathering And Sulfate Export In High Alpine Environments, John T. Crawford, Eve-Lyn S. Hinckley, M. Iggy Litaor, Janice Brahney, Jason C. Neff

Watershed Sciences Faculty Publications

High elevation alpine ecosystems—the 'water towers of the world'—provide water for human populations around the globe. Active geomorphic features such as glaciers and permafrost leave alpine ecosystems susceptible to changes in climate which could also lead to changing biogeochemistry and water quality. Here, we synthesize recent changes in high-elevation stream chemistry from multiple sites that demonstrate a consistent and widespread pattern of increasing sulfate and base cation concentrations or fluxes. This trend has occurred over the past 30 years and is consistent across multiple sites in the Rocky Mountains of the United States, western Canada, the European Alps, the Icelandic …


Agronomic Or Contentious Land Change? A Longitudinal Analysis From The Eastern Brazilian Amazon, Stephen Aldrich, Cynthia S. Simmons, Eugenio Arima, Robert T. Walker, Fernando Michelotti, Edna Castro Dec 2019

Agronomic Or Contentious Land Change? A Longitudinal Analysis From The Eastern Brazilian Amazon, Stephen Aldrich, Cynthia S. Simmons, Eugenio Arima, Robert T. Walker, Fernando Michelotti, Edna Castro

Department of Earth and Environmental Systems

Since 1984, nearly 1,000 people have been killed in the Brazilian Amazon due to land conflicts stemming from unequal distribution of land, land tenure insecurity, and lawlessness. During this same period, the region experienced almost complete deforestation (< 8% forest cover by 2010). Land conflict exacts a human toll, but it also affects agents’ decisions about land use, the subject of this article. Using a property-level panel dataset covering the period of redemocratization in Brazil (1984) until the privatization of long-term leases in the eastern Amazon (2010), we show that deforestation is affected by land conflict, particularly in cases of expropriation of property for agrarian reform settlement formation. Deforestation on these settlements is much greater when soils are poor for agriculture and when the land has been the object of past conflict. Deforestation and conflict are episodic, and both agronomic drivers and contentious drivers of land change are active in the region. Ultimately, the outcome of these processes of contentious and agronomic land change is substantial deforestation, regardless of who was in possession and control of the land.


Estimating Carbon Flux From Optically Recording Total Particle Volume At Depths Below The Primary Pycnocline, Alexander B. Bochdansky, Robert B. Dunbar, Dennis A. Hansell, Gerhard J. Herndl Dec 2019

Estimating Carbon Flux From Optically Recording Total Particle Volume At Depths Below The Primary Pycnocline, Alexander B. Bochdansky, Robert B. Dunbar, Dennis A. Hansell, Gerhard J. Herndl

OES Faculty Publications

Optical instruments can rapidly determine numbers and characteristics of water column particles with high sensitivity. Here we show the usefulness of optically assessed total particle volume below the main pycnocline to estimate carbon export in two systems: the open subarctic North Atlantic and the Ross Sea, Antarctica. Both regions exhibit seasonally high phytoplankton production and efficient export (i.e., a strong biological pump). Total particle volumes in the mesopelagic (200-300 m) were significantly correlated with those in the overlying surface mixed layer (50-60 m), indicating that most particles at depth reflect export from the surface. This connectivity, however, is modulated by …


Blaschke Decompositions On Weighted Hardy Spaces And The Unwinding Series, Stephen D. Farnham Dec 2019

Blaschke Decompositions On Weighted Hardy Spaces And The Unwinding Series, Stephen D. Farnham

Dissertations - ALL

Recently, several authors have considered a nonlinear analogue of Fourier series in signal analysis, referred to as either the unwinding series or adaptive Fourier decomposition. In these processes, a signal is represented as the real component of the boundary value of an analytic function F : ∂D → C, and by performing an iterative method to obtain a sequence of Blaschke decompositions, the signal can be efficiently approximated using only a few terms. To better understand the convergence of these methods, the study of Blaschke decompositions on weighted Hardy spaces was initiated by Coifman and Steinerberger, under the assumption that …


Potential Ecological And Socio-Economic Effects Of A Novel Megaherbivore Introduction: The Hippopotamus In Colombia, Amanda L. Subalusky, Elizabeth P. Anderson, German Jimenez, David Post, David Echeverri Lopez, Sebastian Garcia-R., Laura J. Nova Leon, Juan R. Reatiga Parrish, Ana Rojas, Sergio Solari, Luz F. Jimenez-Segura Dec 2019

Potential Ecological And Socio-Economic Effects Of A Novel Megaherbivore Introduction: The Hippopotamus In Colombia, Amanda L. Subalusky, Elizabeth P. Anderson, German Jimenez, David Post, David Echeverri Lopez, Sebastian Garcia-R., Laura J. Nova Leon, Juan R. Reatiga Parrish, Ana Rojas, Sergio Solari, Luz F. Jimenez-Segura

Department of Earth and Environment

Introduced species can have strong ecological, social and economic effects on their non-native environment. Introductions of megafaunal species are rare and may contribute to rewilding efforts, but they may also have pronounced socio-ecological effects because of their scale of influence. A recent introduction of the hippopotamus Hippopotamus amphibius into Colombia is a novel introduction of a megaherbivore onto a new continent, and raises questions about the future dynamics of the socio-ecological system into which it has been introduced. Here we synthesize current knowledge about the Colombian hippopotamus population, review the literature on the species to predict potential ecological and socio-economic …


A Domain Specific Language For Digital Forensics And Incident Response Analysis, Christopher D. Stelly Dec 2019

A Domain Specific Language For Digital Forensics And Incident Response Analysis, Christopher D. Stelly

University of New Orleans Theses and Dissertations

One of the longstanding conceptual problems in digital forensics is the dichotomy between the need for verifiable and reproducible forensic investigations, and the lack of practical mechanisms to accomplish them. With nearly four decades of professional digital forensic practice, investigator notes are still the primary source of reproducibility information, and much of it is tied to the functions of specific, often proprietary, tools.

The lack of a formal means of specification for digital forensic operations results in three major problems. Specifically, there is a critical lack of:

a) standardized and automated means to scientifically verify accuracy of digital forensic tools; …


The Effects Of Automated Grading On Computer Science Courses At The University Of New Orleans, Jerod F A Dunbar Dec 2019

The Effects Of Automated Grading On Computer Science Courses At The University Of New Orleans, Jerod F A Dunbar

University of New Orleans Theses and Dissertations

This is a study of the impacts of the incorporation, into certain points of the Computer Science degree program at the University of New Orleans, of Course Management software with an Autograding component. The software in question, developed at Carnegie Mellon University, is called “Autolab.” We begin by dissecting Autolab in order to gain an understanding of its inner workings. We can then take out understanding of its functionality and apply that to an examination of fundamental changes to courses in the time since they incorporated the software. With that, we then compare Drop, Failure, Withdrawal rate data from before …


Detection Of Whale Acoustic Signals In The Northern Gulf Of Mexico Ladc-Gemm Database, Yingxue Gao Dec 2019

Detection Of Whale Acoustic Signals In The Northern Gulf Of Mexico Ladc-Gemm Database, Yingxue Gao

University of New Orleans Theses and Dissertations

Low-pass Fourier filter, wavelet filter, as well as matched filter detection methods were used to detect baleen whale signals in northern Gulf of Mexico data collected by the Littoral Acoustic Demonstration Center (LADC) consortium. Some potential low frequency signals appeared on the matched filter output figure. The shape of the signals is in line with one of the typical signal shapes of fin whales--vertical down-sweeps with 18s-time interval. Another shape of the signals is in line with one of the call type shapes of Bryde's whales--down-sweeps with 7s-time interval. A high-pass Fourier filter was also used to find toothed whale …


Multi-Agent Narrative Experience Management As Story Graph Pruning, Edward T. Garcia Dec 2019

Multi-Agent Narrative Experience Management As Story Graph Pruning, Edward T. Garcia

University of New Orleans Theses and Dissertations

In this thesis I describe a method where an experience manager chooses actions for non-player characters (NPCs) in intelligent interactive narratives through story graph representation and pruning. The space of all stories can be represented as a story graph where nodes are states and edges are actions. By shaping the domain as a story graph, experience manager decisions can be made by pruning edges. Starting with a full graph, I apply a set of pruning strategies that will allow the narrative to be finishable, NPCs to act believably, and the player to be responsible for how the story unfolds. By …


Measurement Of The Integrated Luminosity Of The Phase 2 Data Of The Belle Ii Experiment, F. Abudinén, I. Adachi, P. Ahlburg, H. Aihara, N. Akopov, A. Aloisio, F. Ameli, L. Andricek, N. Anh Ky, D. M. Asner, H. Atmacan, T. Aushev, V. Aushev, T. Aziz, K. Azmi, V. Babu, S. Baehr, S. Bahinipati, A. M. Bakich, Milind Purohit, Et. Al. Dec 2019

Measurement Of The Integrated Luminosity Of The Phase 2 Data Of The Belle Ii Experiment, F. Abudinén, I. Adachi, P. Ahlburg, H. Aihara, N. Akopov, A. Aloisio, F. Ameli, L. Andricek, N. Anh Ky, D. M. Asner, H. Atmacan, T. Aushev, V. Aushev, T. Aziz, K. Azmi, V. Babu, S. Baehr, S. Bahinipati, A. M. Bakich, Milind Purohit, Et. Al.

Faculty Publications

From April to July 2018, a data sample at the peak energy of the Υ(4S) resonance was collected with the Belle II detector at the SuperKEKB electron-positron collider. This is the first data sample of the Belle II experiment. Using Bhabha and digamma events, we measure the integrated luminosity of the data sample to be (469.3±0.3±3.0) pb-1, where the first uncertainty is statistical and the second is systematic. This work provides a basis for future luminosity measurements at Belle II.


A 100-M-Scale Modeling Study Of A Gale Event On The Lee Side Of A Long Narrow Mountain, Halie Xue, Jian Li, Tingting Qian, Hongping Gu Dec 2019

A 100-M-Scale Modeling Study Of A Gale Event On The Lee Side Of A Long Narrow Mountain, Halie Xue, Jian Li, Tingting Qian, Hongping Gu

Plants, Soils, and Climate Faculty Publications

In this study, a gale event that occurred on the lee side of a long narrow mountain was investigated, together with the associated mountain flows, using a realistic-case large-eddy simulation (LES) that is based on the Weather Research and Forecasting Model. The mountain is located on the southeastern Tibetan Plateau, where approximately 58 gales occur annually, mostly in the afternoons during the winter season. Benefitting from realistic topography and high horizontal resolution as fine as 111 m, the LES can replicate features similar to the wind fields observed during the gale period. Investigation of the early morning wind structure over …


Euclidean Dynamical Triangulations: Running Couplings And Curvature Correlation Functions, Scott David Bassler Dec 2019

Euclidean Dynamical Triangulations: Running Couplings And Curvature Correlation Functions, Scott David Bassler

Dissertations - ALL

Quantum field theories have been incredibly successful at describing many fundamental aspects of reality with great precision, sometimes relying on the powerful computational tool of lattice methods. Gravity has so far eluded a quantum field theory description, leading many to consider alternate theories like String Theory. However, recent results in lattice quantum gravity have brought some renewed interest in the subject. After reviewing the progress made so far in Euclidean Dynamical Triangulations, a lattice theory of gravity, we examine how the couplings of the theory run with scale. We find that the dimensionless couplings $\hat{G}$ and $\hat{\Lambda}$ are not separately …


Applications Of Elastic Modeling, Thermobarometry, And Thermal History Modeling To (Ultra)High-Pressure Metamorphic Rocks, Joseph Patrick Gonzalez Dec 2019

Applications Of Elastic Modeling, Thermobarometry, And Thermal History Modeling To (Ultra)High-Pressure Metamorphic Rocks, Joseph Patrick Gonzalez

Dissertations - ALL

Subduction zones are tectonically active regions that produce seismicity and volcanism during plate convergence and ultimately recycle crustal material into the mantle. Since these regions dictate many global scale tectonic and geochemical processes (i.e. orogenesis, volatile flux into the mantle, etc.), it is important to understand the depth-temperature conditions of mineral reactions during the subduction-exhumation metamorphic cycle. (Ultra)high-pressure ((U)HP) metamorphic rocks, such as blueschists and eclogites, are formed during metamorphism of subducted crust and sediments along relatively cold geothermal gradients. (U)HP metamorphic rocks may be incorporated into the subduction zone accretionary wedge and exhumed, thereby providing a direct records of …


Development And Application Of Nmr Diffusometry And Relaxometry Methodologies To Study Organic-Inorganic Interactions At Nanomaterial Surfaces, Emily Grace Ripka Dec 2019

Development And Application Of Nmr Diffusometry And Relaxometry Methodologies To Study Organic-Inorganic Interactions At Nanomaterial Surfaces, Emily Grace Ripka

Dissertations - ALL

Colloidal nanomaterials like semiconductor quantum dots (QDs) have size-, shape-, and composition-dependent optoelectronic properties with applications ranging from photovoltaics, to sensing, to medical diagnostics and treatment. These materials also have very high surfaceto- volume ratios, with intricate surface chemistries which control nearly every aspect of their chemical, physical, and colloidal properties. The interaction of the surface with the environment is limited via capping the surface of the nanomaterials with a shell of organic capping molecules. The environment-dependent binding of this organic shell is thus an extremely important aspect of nanomaterial design, however the methodologies to probe these interactions in-situ are …


Dark-Binding Process Relevant To Preventing Photosensitized Oxidation: Conformation-Dependent Light And Dark Mechanisms By A Dual-Functioning Diketone, Sarah J. Belh, Niluksha Walalawela, Stas Lekhtman, Alexander Greer Dec 2019

Dark-Binding Process Relevant To Preventing Photosensitized Oxidation: Conformation-Dependent Light And Dark Mechanisms By A Dual-Functioning Diketone, Sarah J. Belh, Niluksha Walalawela, Stas Lekhtman, Alexander Greer

Publications and Research

Few photosensitizers function in both light and dark processes as they usually have no function when the lights are turned off. We hypothesized that light and dark mechanisms in an α-diketone will be decoupled by dihedral rotation in a conformation- dependent binding process. Successful decoupling of these two functions is now shown. Namely, anti- and syn-skewed conformations of 4,4′-dimethylbenzil promote photosensitized alkoxy radical production, whereas the syn conformation promotes a binding shutoff reaction with trimethyl phosphite. Less rotation of the diketone is better suited to the photosensitizing function since phosphite binding arises through the syn conformer of lower stability. The …


Direct And Indirect Effects Of Temperature And Prey Abundance On Bald Eagle Reproductive Dynamics, Joshua H. Schmidt, Judy Putera, Tammy L. Wilson Dec 2019

Direct And Indirect Effects Of Temperature And Prey Abundance On Bald Eagle Reproductive Dynamics, Joshua H. Schmidt, Judy Putera, Tammy L. Wilson

United States National Park Service: Publications

Understanding the mechanisms by which populations are regulated is critical for predicting the effects of large-scale perturbations. While discrete mortality events provide clear evidence of direct impacts, indirect pathways are more difficult to assess but may play important roles in population and ecosystem dynamics. Here, we use multi-state occupancy models to analyze a long-term dataset on nesting bald eagles in south-central Alaska with the goal of identifying both direct and indirect mechanisms influencing reproductive output in this apex predator. We found that the probabilities of both nest occupancy and success were higher in the portion of the study area where …


Green Strategic Planning Approach For International Shipping Activities, Xiaofang Wu, Luoping Zhang, Huan Feng Dec 2019

Green Strategic Planning Approach For International Shipping Activities, Xiaofang Wu, Luoping Zhang, Huan Feng

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Sustainability is a long-term and ultimate goal for international shipping, although it is slowly making progress. The shipping perspective that moves away from “port-to-port” operations to “door-to-door” services also requires international shipping to take a long-term and holistic view instead of fragmented efforts. How to achieve the long-term sustainability goal becomes a key issue for door-to-door international shipping. Hence, green strategic planning for door-to-door international shipping was proposed with green development that puts forward the eco-centric point of view as its basic theory for sustainability. This study used a strategic decision-making approach, a so-called multi-dimensional decision-making (MDDM), coupled with the …