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2011

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Articles 7501 - 7530 of 7765

Full-Text Articles in Physical Sciences and Mathematics

Petrologic, Geochemical, And Geochronologic Constraints On The Tectonic Evolution Of The Southern Appalachian Orogen, Blue Ridge Province Of Western North Carolina, Eric Douglas Anderson Jan 2011

Petrologic, Geochemical, And Geochronologic Constraints On The Tectonic Evolution Of The Southern Appalachian Orogen, Blue Ridge Province Of Western North Carolina, Eric Douglas Anderson

University of Kentucky Doctoral Dissertations

The Blue Ridge Province of western North Carolina contains a wide variety of metamorphosed igneous and sedimentary rocks that record the tectonic effects of Precambrian and Paleozoic orogenic cycles. Tectonic interpretations of the events that led to the present configuration are varied and often conflicting. This investigation examines metamorphosed mafic rocks that are widely interpreted to have formed during the closure of ocean basins. Metabasites, and specifically eclogites, have a tendency to mark tectonic sutures and frequently preserve pressure (P), temperature (T), and age data (t) that can be gleaned from mineral equilibria and U-Pb isotopic compositions. As such, the …


Fabrication And Characterization Of Mesoscale Protein Patterns Using Atomic Force Microscopy (Afm), Pei Gao Jan 2011

Fabrication And Characterization Of Mesoscale Protein Patterns Using Atomic Force Microscopy (Afm), Pei Gao

University of Kentucky Doctoral Dissertations

A versatile AFM local oxidation lithography was developed for fabricating clean protein patterns ranging from nanometer to sub-millimeter scale on octadecyltrichlorosilane (OTS) layer of Si (100) wafer. This protein patterning method can generate bio-active protein pattern with a clean background without the need of the anti-fouling the surface or repetitive rinsing.

As a model system, lysozyme protein patterns were investigated through their binding reactions with antibodies and aptamers by AFM. Polyclonal anti-lysozyme antibodies and anti-lysozyme aptamer are found to preferentially bind to the lysozyme molecules on the edge of a protein pattern before their binding to the interior ones. It …


Interactions And Effects Of Biomolecules On Au Nanomaterial Surfaces, Manish Sethi Jan 2011

Interactions And Effects Of Biomolecules On Au Nanomaterial Surfaces, Manish Sethi

University of Kentucky Doctoral Dissertations

Au nanoparticles are increasingly being used in biological applications. Their use is of interest based upon their unique properties that are achieved at the nanoscale, which includes strong optical absorbances that are size and aggregation state dependent. Such absorbances can be used in sensitive chemical/biological detection schemes where bioligands can be directly attached to the nanoparticle surface using facile methods. Unfortunately, a number of complications persist that prevent their wide-scale use. These limitations include minimal nanoparticle stability in biological-based media of high ionic strength, unknown surface functionalization effects using simple biomolecules, and determining the binding motifs of the ligands to …


Resource Allocation And Efficient Routing In Wireless Networks, Jianjun Yang Jan 2011

Resource Allocation And Efficient Routing In Wireless Networks, Jianjun Yang

University of Kentucky Doctoral Dissertations

In wireless networks, devices (nodes) are connected by wireless links. An important issue is to set up high quality (high bandwidth) and efficient routing paths when one node wants to send packets to other nodes. Resource allocation is the foundation to guarantee high quality connections. In addition, it is critical to handle void areas in order to set up detour-free paths. Moreover, fast message broadcasting is essential in mobile wireless networks. Thus, my research includes dynamic channel allocation in wireless mesh networks, geographic routing in Ad Hoc networks, and message broadcasting in vehicular networks.

The quality of connections in a …


Conceptualizing And Improving Red Wine Grape Cultivars Grown In Kentucky, Matthew Simson Jan 2011

Conceptualizing And Improving Red Wine Grape Cultivars Grown In Kentucky, Matthew Simson

University of Kentucky Master's Theses

Wine sensory attributes are associated with quality of wines. Cabernet Franc did not possess good coloration of its wine. Therefore, in the 2009 and 2010 growing seasons, studies including the sampling of four red wine grape cultivars from the end of flowering throughout the rest of the season and applying treatments to Cabernet Franc grapevines at veraison were commenced to address suitability and color enhancement, respectively. The study examining Cabernet Franc, Cabernet Sauvignon, Chambourcin, and Norton looked at sampling their grapes at two-week intervals from times post-flowering to understand the demands of each cultivar during key stages of berry development, …


A Classification Of Lower Paleozoic Carbonate-Bearing Rocks For Geotechnical Applications, Bethany L. Overfield Jan 2011

A Classification Of Lower Paleozoic Carbonate-Bearing Rocks For Geotechnical Applications, Bethany L. Overfield

University of Kentucky Master's Theses

An empirically-based classification of lower Paleozoic carbonate-bearing rocks was created for field-based geotechnical applications. Geotechnical parameters were subsequently correlated to that classification. Seven hundred seventy-seven samples were used as the basis for the classification. Thirteen categories based on visual and tactile properties and a hydrochloric acid test were created. Samples were from central, north-central, and south-central Kentucky and represented the majority of Ordovician exposures in the state, and some Mississippian exposures. Few Silurian and Devonian units were included in the sample set. Geotechnical parameters, including density as well as elastic constants (shear and compression wave velocities, Poisson’s ratio, Young’s modulus, …


Investigation Of The Toxicity And Efflux Of Polychlorinated Biphenyls And Hydroxylated Polychlorinated Biphenyls In Escherichia Coli, Shen Geng Jan 2011

Investigation Of The Toxicity And Efflux Of Polychlorinated Biphenyls And Hydroxylated Polychlorinated Biphenyls In Escherichia Coli, Shen Geng

University of Kentucky Master's Theses

Polychlorinated biphenyls (PCBs) are persistent organic pollutants. Due to their properties, PCBs accumulate in the food-chain and post a threat to the health of human beings and wildlife. Hydroxylated PCBs (OH-PCBs) are oxidative metabolites of PCBs and are more hydrophilic than their parent PCBs. One of the best approaches to break down these contaminants is through bioremediation, which is an environmental friendly process that uses microorganisms to restore natural environment.

Towards this goal, we have investigated the toxicity and accumulation of PCBs and OH-PCBs in a Gram-negative bacterium, Escherichia coli. We have also determined the role played by a …


Determining Interstellar Reddening: A New Approach Using Spectroscopy And Photometry, Syed A. Uddin Jan 2011

Determining Interstellar Reddening: A New Approach Using Spectroscopy And Photometry, Syed A. Uddin

University of Kentucky Master's Theses

The mystery of Canis Major overdensity is addressed. We discuss concurrent methods and their limitations on the determination of interstellar reddening. We establish a new way to determine line of sight interstellear reddening by observing stellar spectral lines and UBV colors. We observe and analyze spectra of 22 stars in different open clusters. We find that Hydrogen Balmer line at 4861 angstrom can predict the stellar atmospheric parameters and intrinsic colors with reasonable accuracy. Comparing with observed colors we derive the reddening of the stars. We compare our results with standard database WEBDA and find that within 90% probability limit …


Physical Conditions In A Galactic Star Forming Region W22, Akshaya Rane Jan 2011

Physical Conditions In A Galactic Star Forming Region W22, Akshaya Rane

University of Kentucky Master's Theses

This document describes study of an active star forming region in our galaxy (the Milky Way) known as W22. Physical conditions in these regions can help us in understanding star formation processes in the universe and hence the structure and evolution of the universe. Zeeman effect measurements in 18 cm OH absorption line were carried out in order to estimate the line of sight magnetic field strength in the molecular cloud associated with this star forming region. Other physical parameters such as hydrogen column density, optical depth, critical magnetic field were also determined from these measurements. The region was mapped …


Ignition Of A Large Volume Plasma With A Plasma Jet, M. Laroussi, M. A. Akman Jan 2011

Ignition Of A Large Volume Plasma With A Plasma Jet, M. Laroussi, M. A. Akman

Electrical & Computer Engineering Faculty Publications

Here we report on a method to generate a long plasma plume and to ignite a large volume plasma by means of the jet. The plasma plume is generated by our tube reactor and then introduced into a chamber where the pressure is controlled. We discovered there are three operating phases:Aphasewhere the plume length remains approximately constant, followed by a second phase where the jet increases in length as the pressure decreases. Then at pressures below 70 Torr a mode transition occurs where the plume length decreases and the plasma expands until the entire chamber is filled.


Unitary-Quantum-Lattice Algorithm For Two-Dimensional Quantum Turbulence, Bo Zhang, George Vahala, Linda L. Vahala, Min Soe Jan 2011

Unitary-Quantum-Lattice Algorithm For Two-Dimensional Quantum Turbulence, Bo Zhang, George Vahala, Linda L. Vahala, Min Soe

Electrical & Computer Engineering Faculty Publications

Quantum vortex structures and energy cascades are examined for two-dimensional quantum turbulence (2D QT) at zero temperature. A special unitary evolution algorithm, the quantum lattice algorithm, is employed to simulate the Bose-Einstein condensate governed by the Gross-Pitaevskii (GP) equation. A parameter regime is uncovered in which, as in 3D QT, there is a short Poincare recurrence time. It is demonstrated that such short recurrence times are destroyed by stronger nonlinear interaction. The similar loss of Poincare recurrence is also seen in the 3D GP equation. Various initial conditions are considered in an attempt to discern if 2D QT exhibits inverse …


Poincare Recurrence And Spectral Cascades In Three-Dimensional Quantum Turbulence, George Vahala, Jeffrey Yepez, Linda L. Vahala, Min Soe, Bo Zhang, Sean Ziegeler Jan 2011

Poincare Recurrence And Spectral Cascades In Three-Dimensional Quantum Turbulence, George Vahala, Jeffrey Yepez, Linda L. Vahala, Min Soe, Bo Zhang, Sean Ziegeler

Electrical & Computer Engineering Faculty Publications

The time evolution of the ground state wave function of a zero-temperature Bose-Einstein condensate (BEC) gas is well described by the Hamiltonian Gross-Pitaevskii (GP) equation. Using a set of appropriately interleaved unitary collision-stream operators, a qubit lattice gas algorithm is devised, which on taking moments, recovers the Gross-Pitaevskii (GP) equation under diffusion ordering (time scales as length2). Unexpectedly, there is a class of initial states whose Poincaré recurrence time is extremely short and which, as the grid resolution is increased, scales with diffusion ordering (and not as length3). The spectral results of J. Yepez et al. …


Localized Surface Plasmon Resonance Of Single Silver Nanoparticles Studied By Dark-Field Optical Microscopy And Spectroscopy, Wei Cao, Tao Huang, Xiao-Hong Nancy Xu, Hani E. Elsayed-Ali Jan 2011

Localized Surface Plasmon Resonance Of Single Silver Nanoparticles Studied By Dark-Field Optical Microscopy And Spectroscopy, Wei Cao, Tao Huang, Xiao-Hong Nancy Xu, Hani E. Elsayed-Ali

Electrical & Computer Engineering Faculty Publications

Localized surface plasmon resonance (LSPR) of Ag nanoparticles (NPs) with different shapes and disk-shaped Ag NP pairs with varying interparticle distance is studied using dark-field optical microscopy and spectroscopy (DFOMS). Disk-, square-, and triangular-shaped Ag NPs were fabricated on indium tin oxide-coated glass substrates by electron beam lithography. The LSPR spectra collected from single Ag NPs within 5×5 arrays using DFOMS exhibited pronounced redshifts as the NP shape changed from disk to square and to triangular. The shape-dependent experimental LSPR spectra are in good agreement with simulations using the discrete dipole approximation model, although there are small deviations in the …


Anisotropic Response Of Nanosized Bismuth Films Upon Femtosecond Laser Excitation Monitored By Ultrafast Electron Diffraction, Ahmed R. Esmail, Hani E. Elsayed-Ali Jan 2011

Anisotropic Response Of Nanosized Bismuth Films Upon Femtosecond Laser Excitation Monitored By Ultrafast Electron Diffraction, Ahmed R. Esmail, Hani E. Elsayed-Ali

Electrical & Computer Engineering Faculty Publications

The lattice response of 5 nm thick bismuth film to femtosecond laser excitation is probed by ultrafast electron diffraction. The transient decay time after laser excitation is greater for diffraction from (012) lattice planes compared to (110) planes and is reduced for both planes with the increased laser fluence. These results indicate that different energy coupling mechanisms to the lattice occur depending on the crystal direction. The behavior of the diffraction peak width indicates partial disorder of the film upon photoexcitation that increases together with the laser fluence. © 2011 American Institute of Physics. [doi:10.1063/1.3652919]


New Photovoltaic Acceptors: Synthesis And Characterization Of Functionalized C-Fused Anthradithiophene Quinones, Kerri Shelton Jan 2011

New Photovoltaic Acceptors: Synthesis And Characterization Of Functionalized C-Fused Anthradithiophene Quinones, Kerri Shelton

University of Kentucky Master's Theses

Stable organic semiconductors are critical to produce inexpensive, efficient and flexible thin film organic solar cells. A current chemical focus is the synthesis of stable, electron-accepting materials to be utilized as an acceptor layer in photovoltaics.1 The Anthony group has shown that the functionalization of pentacene with suitable electron withdrawing groups provides a catalog of suitable acceptors for this purpose.2 These pentacenes can be further modified to pack in a unique 1-dimensional "sandwich herringbone" crystal packing, leading to improved device current.3 To improve the stability of acene acceptors, we have taken two hetero-atom themed approaches. First, we …


Development Of Novel Electrophilic Ruthenium(Ii) And Iridium(Iii) Complexes And Their Applications As Homogeneous Catalysts, Ryan R. Ketcham Jan 2011

Development Of Novel Electrophilic Ruthenium(Ii) And Iridium(Iii) Complexes And Their Applications As Homogeneous Catalysts, Ryan R. Ketcham

University of Kentucky Master's Theses

Our aim was to develop the synthetic potential and reaction chemistry of Ir3+ and Ru2+ electrophiles by preparing well-characterized complexes whose properties are controllable by modification of the ancillary ligand environment Specifically, we prepared a series of ruthenium complexes to serve as selective hydrogenation and hydrogenolysis catalysts of furan derivatives. We also expanded the synthesis of electrophilic Ir3+ di-thiolate complexes. These types of compounds could eventually serve as catalysts precursors for the addition of weak nucleophiles to alkynes and nitriles.


A Reliability-Based Routing Protocol For Vehicular Ad-Hoc Networks, James Bernsen Jan 2011

A Reliability-Based Routing Protocol For Vehicular Ad-Hoc Networks, James Bernsen

University of Kentucky Master's Theses

Vehicular Ad hoc NETworks (VANETs), an emerging technology, would allow vehicles to form a self-organized network without the aid of a permanent infrastructure. As a prerequisite to communication in VANETs, an efficient route between communicating nodes in the network must be established, and the routing protocol must adapt to the rapidly changing topology of vehicles in motion. This is one of the goals of VANET routing protocols. In this thesis, we present an efficient routing protocol for VANETs, called the Reliable Inter-VEhicular Routing (RIVER) protocol. RIVER utilizes an undirected graph that represents the surrounding street layout where the vertices of …


Fate Of Stable Isotope Label During Predation Of 15N-Tagged Wild-Type Escherichia Coli By Protozoa, Ashley M. Barton Jan 2011

Fate Of Stable Isotope Label During Predation Of 15N-Tagged Wild-Type Escherichia Coli By Protozoa, Ashley M. Barton

University of Kentucky Master's Theses

Currently, bacterial movement in karst aquifers is not well understood. Use of stable isotopes to label non-pathogenic Escherichia coli as a particulate groundwater tracer in karst systems has been examined in previous studies. Loss of the stable isotope signal is anticipated in traces greater than 500 m in length. Potential loss of 15N due to predation by protozoa was examined. Filter-sterilized water from Royal Spring in Georgetown, Kentucky, was inoculated with a mixture of either Tetrahymena pyriformis or Colpoda steinii and 15N-enriched E. coli and stored in the dark at 14°C. Samples were analyzed for their nitrogen isotope …


Robust Integral Of Neural Network And Sign Of Tracking Error Control Of Uncertain Nonlinear Affine Systems Using State And Output Feedback, Qinmin Yang, Sarangapani Jagannathan, Youxian Sun Jan 2011

Robust Integral Of Neural Network And Sign Of Tracking Error Control Of Uncertain Nonlinear Affine Systems Using State And Output Feedback, Qinmin Yang, Sarangapani Jagannathan, Youxian Sun

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents a novel state and output feedback control law for the tracking control of a class of multi-input-multi-output (MIMO) continuous time nonlinear systems with unknown dynamics and disturbance input. First the state feedback-based control law is designed which consists of the robust integral of a neural network (NN) output plus the sign of the tracking error signal multiplied with an adaptive gain. the two-layer NN learns the system dynamics in an online manner while the NN residual reconstruction errors and the bounded system disturbances are overcome by the error sign signal. Both of the NN output and error …


Do We Need M&S Science?, Jose J. Padilla, Saikou Y. Diallo, Andreas Tolk Jan 2011

Do We Need M&S Science?, Jose J. Padilla, Saikou Y. Diallo, Andreas Tolk

VMASC Publications

No abstract provided.


Stochastic Optimal Control Design For Nonlinear Networked Control System Via Neuro Dynamic Programming Using Input-Output Measurements, Hao Xu, Sarangapani Jagannathan Jan 2011

Stochastic Optimal Control Design For Nonlinear Networked Control System Via Neuro Dynamic Programming Using Input-Output Measurements, Hao Xu, Sarangapani Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

Neuro dynamic programming (NDP) techniques for optimal control of nonlinear network control system (NNCS) are not addressed in the literature. Therefore, in this paper, a novel NNCS representation incorporating the unknown system uncertainties and network imperfections is introduced first by using input and output measurements. Then, an online neural network (NN) identifier is introduced to estimate the control coefficient matrix. Subsequently, the critic NN and action NN are employed along with the NN identifier to determine the forward-in-time, time-Based stochastic optimal control of NNCS without using value and policy iterations. Instead, value function and control inputs are updated at every …


Investigation Of Synthetic Methods For Preparation Of 2O-Amino Derivatives Of 5-Amino- 1, 10-Phenanthroline: Applications To Cu+2 Based Impedance Sensors, Satish B. Chunchu Jan 2011

Investigation Of Synthetic Methods For Preparation Of 2O-Amino Derivatives Of 5-Amino- 1, 10-Phenanthroline: Applications To Cu+2 Based Impedance Sensors, Satish B. Chunchu

Master's Theses and Doctoral Dissertations

The main purpose of this project is to synthesize 2o - derivatives of 5-amino-1, 10- phenanthroline (5-aphen) for application as self-assembled monolayers on gold interdigitated electrode array chips in standard impedance and impedance resonance-based Cu2+ sensors. Potential applications include monitoring Cu2+ leaching from anti-fouling coatings on ship hulls. The importance of the planned secondary alkyl amino derivatives will be to test their binding properties to the gold surface through dithiocarbamate linkages by monitoring the IDE impedance signal. Practical sensor development requires good impedance response, maximum binding to the gold IDE chip, and maximum long term stability of …


Paley-Wiener Theorems With Respect To The Spectral Parameter, Susanna Dann Jan 2011

Paley-Wiener Theorems With Respect To The Spectral Parameter, Susanna Dann

LSU Doctoral Dissertations

One of the important questions related to any integral transform on a manifold M or on a homogeneous space G/K is the description of the image of a given space of functions. If M=G/K, where (G,K) is a Gelfand pair, then harmonic analysis on M is closely related to the representations of G and the direct integral decomposition of L^2(M) into irreducible representations of G. R^n can be realized as the quotient R^n=E(n)/SO(n), where E(n) is the orientation preserving Euclidean motion group. The pair (E(n), SO(n)) is a Gelfand pair. Hence this realization of R^n comes with its own natural …


Towards Transient Growth Analysis And Design In Iterative Learning Control, Douglas A. Bristow, John R. Singler Jan 2011

Towards Transient Growth Analysis And Design In Iterative Learning Control, Douglas A. Bristow, John R. Singler

Mechanical and Aerospace Engineering Faculty Research & Creative Works

In this article the problem of bounding transient growth in iterative learning control (ILC) is examined. While transient growth is not a desirable property, the alternative, robust monotonic convergence, leads to fundamental performance limitations. to circumvent these limitations, this article considers the possibility that some transient growth, if properly limited, is a viable and practical option. Towards this end, this article proposes tools for analysing worst-case transient growth in ILC. the proposed tools are based on pseudospectra analysis, which is extended to apply to ILC of uncertain systems. Two practical problems in norm-optimal ILC weighting parameter design are considered. Using …


Classroom Manipulative To Engage Students In Mathematical Modeling Of Disease Spread: 1 + 1 = Achoo!, H. Gaff, M. Lyons, G. Watson Jan 2011

Classroom Manipulative To Engage Students In Mathematical Modeling Of Disease Spread: 1 + 1 = Achoo!, H. Gaff, M. Lyons, G. Watson

Biological Sciences Faculty Publications

Infectious diseases ranging from the common cold to cholera affect our society physically, emotionally, ecologically, and economically. Yet despite their importance and impact, there remains a lack of effective teaching materials for epidemiology and disease ecology in K-12, undergraduate, and graduate curricula [2]. To address this deficit, we've developed a classroom lesson with three instructional goals: (1) Familiarize students on basic concepts of infectious disease ecology; (2) Introduce students to a classic compartmental model and its applications in epidemiology; (3) Demonstrate the application and importance of mathematical modeling as a tool in biology. The instructional strategy uses a game-based mathematical …


Draft Genome Sequence Of Strain Himb100, A Cultured Representative Of The Sar116 Clade Of Marine Alphaproteobacteria, Jana Grote, Cansu Bayindirli, Kristin Bergauer, Paula C. De Moraes, Huan Chen, Lindsay D'Ambrosio, Bethany Edwards, Beatriz Fernandez-Gomez, Mariam Hamisi, Dan Nguyen, Yoshimi M. Rii, Emily Saeck, Charles Schutte, Brittany Widner Jan 2011

Draft Genome Sequence Of Strain Himb100, A Cultured Representative Of The Sar116 Clade Of Marine Alphaproteobacteria, Jana Grote, Cansu Bayindirli, Kristin Bergauer, Paula C. De Moraes, Huan Chen, Lindsay D'Ambrosio, Bethany Edwards, Beatriz Fernandez-Gomez, Mariam Hamisi, Dan Nguyen, Yoshimi M. Rii, Emily Saeck, Charles Schutte, Brittany Widner

OES Faculty Publications

Strain HIMB100 is a planktonic marine bacterium in the class Alphaproteobacteria. This strain is of interest because it is one of the first known isolates from a globally ubiquitous clade of marine bacteria known as SAR116 within the family Rhodospirillaceae. Here we describe preliminary features of the organism, together with the draft genome sequence and annotation. This is the second genome sequence of a member of the SAR116 clade. The 2,458,945 bp genome contains 2,334 protein-coding and 42 RNA gene


Florida Straits Deglacial Temperature And Salinity Change: Implications For Tropical Hydrologic Cycle Variability During The Younger Dryas, Matthew W. Schmidt, Jean Lynch-Stieglitz Jan 2011

Florida Straits Deglacial Temperature And Salinity Change: Implications For Tropical Hydrologic Cycle Variability During The Younger Dryas, Matthew W. Schmidt, Jean Lynch-Stieglitz

OES Faculty Publications

The prevailing paradigm of abrupt climate change holds that rapid shifts associated with the most extreme climate swings of the last glacial cycle were forced by changes in the strength and northward extension of Atlantic Meridional Overturning Circulation (AMOC), resulting in an abrupt reorganization of atmospheric circulation patterns with global teleconnections. To determine the timing of tropical Atlantic atmospheric circulation changes over the past 21 ka BP, we reconstruct high resolution sea surface temperature and δ18OSW (a proxy for surface salinity) records based on Mg/Ca ratios and oxygen isotope measurements in the planktonic foraminifera Globigerinoides ruber from …


Meridional Shifts In The Marine Itcz And The Tropical Hydrologic Cycle Over The Last Three Glacial Cycles, Matthew W. Schmidt, Howard J. Spero Jan 2011

Meridional Shifts In The Marine Itcz And The Tropical Hydrologic Cycle Over The Last Three Glacial Cycles, Matthew W. Schmidt, Howard J. Spero

OES Faculty Publications

Paleoproxy studies show a strong correlation between tropical climate and high-latitude temperature variability recorded in the Greenland ice cores over the last glacial cycle. In particular, abrupt cooling events in the Greenland Ice Sheet Project II δ18O ice record appear synchronous with a southward migration of the Intertropical Convergence Zone (ITCZ) in the Atlantic, a weakening of the Indian and East Asian monsoon systems, and a strengthening of the South American monsoon system. Because this high-to-low-latitude climate teleconnection significantly alters the tropical hydrologic cycle around the globe, it plays a critical role in regulating global climate on glacial-interglacial …


Lithospheric Control On The Spatial Pattern Of Azores Hotspot Seafloor Anomalies: Constraints From A Model Of Plume-Triple Junction Interaction, Jennifer E. Georgen Jan 2011

Lithospheric Control On The Spatial Pattern Of Azores Hotspot Seafloor Anomalies: Constraints From A Model Of Plume-Triple Junction Interaction, Jennifer E. Georgen

OES Faculty Publications

The Azores hotspot is located near a plate boundary triple junction (TJ) consisting of the Terceira Rift (TER) and two branches of the Mid-Atlantic Ridge (MAR). The seafloor expression of the Azores hotspot has a complex spatial pattern. Latitudinal anomalies in seafloor depth and other data along the MAR extend farther to the south of the inferred location of the mantle heterogeneity than to the north. Longitudinal anomalies span a greater distance to the east of the MAR (along the TER) than to the west. A finite element model is used to investigate how the divergence of three plates away …


Abundance Of Eukaryotic Microbes In The Deep Subtropical North Atlantic, Danielle Morgan-Smith, Gerhard J. Herndl, Hendrik M. Van Aken, Alexander B. Bochdansky Jan 2011

Abundance Of Eukaryotic Microbes In The Deep Subtropical North Atlantic, Danielle Morgan-Smith, Gerhard J. Herndl, Hendrik M. Van Aken, Alexander B. Bochdansky

OES Faculty Publications

The meso- and bathypelagic ocean comprises the largest habitat on earth, yet we know very little about the distribution and activity of protists in this environment. These small eukaryotes are responsible for controlling bacterial abundance in the surface ocean and are major players in the material and energy transfer of pelagic food webs. In this paper, we quantify microbial eukaryotes in the deep North Atlantic, as well as provide a basic characterization of eukaryote community changes through the water column. To this end, we counted organisms using 2 different approaches: (1) catalyzed reporter deposition fluorescence in situ hybridization (CARD-FISH, also …