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Photonic Tools For Advanced Sensing And Imaging At The Nanoscale., Jafar Hamed Ghithan 2018 University of Louisville

Photonic Tools For Advanced Sensing And Imaging At The Nanoscale., Jafar Hamed Ghithan

Electronic Theses and Dissertations

This dissertation reports a novel bio-sensing strategy based on single-mode, electro-active, integrated optical waveguide (SM-EA-IOW) platforms. It also reports the development of a super-resolved far-field optical imaging tool to enable optical, electronic, and spectroelectrochemical investigations at the nanoscale. SM-EA-IOW platforms with its outstanding sensitivity for spectroelectrochemical interrogation was combined with a sandwich bioassay for the development of a novel immunosensing based strategy for label-free detection of infectious pathogens. The strategy begins with the functionalization of the electroactive waveguide surface with a capturing antibody aimed at a specific target analyte. Once the target analyte is bound to the photonic interface, it …


Combining Microdialysis And Electrophysiology In Cerebral Cortex To Delineate Functional Implications Of Acetylcholine Gradients, Tazima Nur 2018 University of Arkansas, Fayetteville

Combining Microdialysis And Electrophysiology In Cerebral Cortex To Delineate Functional Implications Of Acetylcholine Gradients, Tazima Nur

Graduate Theses and Dissertations

The neuronal network in cerebral cortex is a dynamic system that can undergo changes in collective neural activity as the organism changes its behavior. For example, during sleep and quiet restful awake state, many neurons tend to fire together in synchrony. In contrast, during alert awake states, firing patterns of neurons tend to be more asynchronous, firing more independently. These changes in population-level synchrony are defined as changes in cortical state. Response to sensory input is state-dependent, i.e., change in cortical state can impact the sensory information processing in cortex and introduce trial-to-trial variability in response to the same repeated …


The Incorporation Of Graphene To Lithium Cobalt Oxide As A Cathode To Improve The Performance Of Lithium Ion Batteries, Kenan Wang 2018 University of Arkansas, Fayetteville

The Incorporation Of Graphene To Lithium Cobalt Oxide As A Cathode To Improve The Performance Of Lithium Ion Batteries, Kenan Wang

Graduate Theses and Dissertations

One of the objectives of this thesis work was to investigate the cathode performance of lithium cobalt oxide (LiCoO2) incorporated with graphene powder in lithium ion batteries (LIBs). Graphene powder was incorporated into cathode materials to enhance the performance of LIBs. The other objective was to impede the construction of a solid electrolyte interphase (SEI) sheet using graphene sheet coating on its cathode.

The results of this work show that adding graphene powder improved the performance of LiCoO¬2 as a cathode material. With the incorporation of different weight percentages of graphene powder, the LiBs showed distinct changes in their charging …


Sex Differences In Lower Limb Biomechanics During A Single-Leg Cut With Body Borne Load, AuraLea Carylon Fain 2018 Boise State University

Sex Differences In Lower Limb Biomechanics During A Single-Leg Cut With Body Borne Load, Auralea Carylon Fain

Boise State University Theses and Dissertations

Introduction: Musculoskeletal injuries are ever-increasing in military personnel, particularly females. These musculoskeletal injuries are attributed to adaptations in lower limb biomechanics while performing routine military tasks, such as a single-leg cut, with the addition of body borne load. However, it is unknown if females and males exhibit similar lower limb biomechanics with the addition of body borne load during these tasks. This study sought to compare the lower limb biomechanical adaptations exhibited by females and males performing a single-leg cut with body borne load. Methods: Eleven females and 17 males had lower limb biomechanics quantified during a single-leg cut with …


Pregnancy Induced Alterations Of Reproductive Tract Collagen And Elastin In A Murine Model, Basant K. Dhital 2018 The Graduate Center, City University of New York

Pregnancy Induced Alterations Of Reproductive Tract Collagen And Elastin In A Murine Model, Basant K. Dhital

Dissertations, Theses, and Capstone Projects

This thesis reports on structural and dynamical modifications of reproductive tract elastin and collagen as a function of parity. Pelvic floor dysfunction, including pelvic organ prolapse (POP) is a major concern affecting female health worldwide, leading to surgeries costing billions of dollars annually. Collagen, elastic fibers, and proteoglycans are major extracellular matrix (ECM) components found in connective tissues. Vaginal child birth, advancing age, and disruption or dysfunction of connective tissue are major risk factors of POP. In the female reproductive tract, the assembly of elastic fibers is crucial for the pelvic floor support. Any disturbance in the synthesis, assembly, and …


Achieving A Stable Magneto-Optical Trap, Chasen S. Himeda 2018 Loyola Marymount University

Achieving A Stable Magneto-Optical Trap, Chasen S. Himeda

Honors Thesis

The utilization of the Magneto-Optical Trap (MOT) as a method for cooling and confining atoms is a recent development in the field of modern optical physics. Producing an effective MOT relies on a constant magnetic field throughout the trapping region and successful laser cooling, a technique used to achieve optical molasses by slowing particles using a three-dimensional intersection of laser beams. A successful MOT occurs when the trapped atoms slow down to approximately 30 cm/s at a temperature in the microkelvin range and is observable when a small bright orb of atoms is located in the center of the chamber. …


Compact Sensing Platforms Based On Localized Surface Plasmon Resonance, Zhutian Ding 2018 The University of Western Ontario

Compact Sensing Platforms Based On Localized Surface Plasmon Resonance, Zhutian Ding

Electronic Thesis and Dissertation Repository

The development of plasmonic sensors mainly focuses on the improvement of their sensitivities that are approaching the theoretical limit. This work aims to propose, fabricate and characterize compact sensing platforms that are highly adaptable and easy to be miniaturized, without compromising their sensitivities. A plasmonic sensing system that allows the excitation of localized surface plasmon resonance (LSPR) by individual waveguide modes is presented conceptually and experimentally. Another compact sensing platform is proposed based on the ensemble hypothesis developed in this thesis.


The Association Of Size Variation In The Dental Arch To Third Molar Agenesis For A Modern Population, Devin N. Williams 2018 University of South Florida

The Association Of Size Variation In The Dental Arch To Third Molar Agenesis For A Modern Population, Devin N. Williams

USF Tampa Graduate Theses and Dissertations

The frequency with which individuals do not develop their third molars, or wisdom teeth, is increasing worldwide. This current topic of human evolution is relevant to the research of anthropologists, geneticists, dentists, and other researchers involved in the study of human dentition. Many explanations have been offered to account for the prevalence of molar agenesis including, evolutionary, environmental, and genetic theories. The purpose of this research project is to determine the frequency of third molar agenesis and investigate the relationship between third molar agenesis and maxillomandibular jaw dimensions in a sample of orthodontic patients. This research tests the hypotheses that: …


Vibration Response: Mapping The Behavioral Response Of Fruit Fly Larvae To Mechanical Stimuli, Alexander Berne 2018 University of Miami

Vibration Response: Mapping The Behavioral Response Of Fruit Fly Larvae To Mechanical Stimuli, Alexander Berne

2018 Entries

Drosophila larvae are capable of a wide array of simple, quantifiable behavioral responses to stimuli, which makes the organism a useful tool for deconstructing biotic behavior for wider application. To this end, an understanding of the response to mechanical stimulation remains relatively unexplored in this organism, and warrants investigation. This research aims to map the fruit fly’s behavior as a function of a generalized mechanical stimulus, namely, vibration.

Fruit fly larvae are placed in a light and temperature controlled environment, and observed crawling on vibrating agar plates with CCD cameras controlled through LabVIEW. Larvae are monitored for their instantaneous speed, …


Evolving Specialization In An Agent-Based Model Without Task-Switching Costs, Shane Meyer 2018 University of Missouri, St. Louis

Evolving Specialization In An Agent-Based Model Without Task-Switching Costs, Shane Meyer

Dissertations

This work examines the possibility of evolving the phenotypic specialization associated with division of labor in an agent-based model without task-switching costs. The model examines two groups competing for vital resources, where members of one group are capable of sharing resources with other agents in their group. Agents attempt to collect resources which allow them to reproduce, with more resources leading to a greater number of offspring by asexual reproduction. Four variants of the model are examined, with combinations of one or two resources and the presence of a foraging risk. The presence of the foraging risk can lead to …


Reference Dependence Of The Two-Determinant Coupled-Cluster Method For Triplet And Open-Shell Singlet States Of Biradical Molecules, Jesse J. Lutz, Marcel Nooijen, Ajith Perera, Rodney J. Bartlett 2018 Air Force Institute of Technology

Reference Dependence Of The Two-Determinant Coupled-Cluster Method For Triplet And Open-Shell Singlet States Of Biradical Molecules, Jesse J. Lutz, Marcel Nooijen, Ajith Perera, Rodney J. Bartlett

Faculty Publications

We study the performance of the two-determinant (TD) coupled-cluster (CC) method which, unlike conventional ground-state single-reference (SR) CC methods, can, in principle, provide a naturally spin-adapted treatment of the lowest-lying open-shell singlet (OSS) and triplet electronic states. Various choices for the TD-CC reference orbitals are considered, including those generated by the multi-configurational self-consistent field method. Comparisons are made with the results of high-level SR-CC, equation-of-motion (EOM) CC, and multi-reference EOM calculations performed on a large test set of over 100 molecules with low-lying OSS states. It is shown that in cases where the EOMCC reference function is poorly described, TD-CC …


Nadph-Cytochrome P450 Oxidoreductase: Extraction Of The Full-Length Protein And Methyl-Trosy Nmr Of The Soluble Mutants, Sara Ali Jamal Arafeh 2018 Marquette University

Nadph-Cytochrome P450 Oxidoreductase: Extraction Of The Full-Length Protein And Methyl-Trosy Nmr Of The Soluble Mutants, Sara Ali Jamal Arafeh

Master's Theses (2009 -)

NADPH-cytochrome p450 oxidoreductase (CYPOR) is a membrane-bound protein in living cells. CYPOR delivers electrons to cytochrome p450 proteins (CYPs) to catalyze metabolism of drugs and synthesis of steroids. Extraction and solubilization of CYPOR from the membrane is typically done with the TritonX-100 detergent. The amount of the solubilized protein by this detergent, however, remains relatively low to structurally analyze CYPOR with NMR spectroscopy. The goal of the first project in this thesis was to optimize the amount of the extracted CYPOR from the E. coli membrane using various detergents and additives. To this aim, non-ionic detergents with variable hydrophobicity (TritonX-100, …


Hyperpolarization Of Silicon Nanoparticles With Tempo Radicals, Jingzhe Hu, Nicholas Whiting, Pratip Bhattacharya 2018 University of Texas MD Anderson Cancer Center

Hyperpolarization Of Silicon Nanoparticles With Tempo Radicals, Jingzhe Hu, Nicholas Whiting, Pratip Bhattacharya

Nicholas Whiting

Silicon-based particles can be hyperpolarized via dynamic nuclear polarization to enhance 29Si magnetic resonance signals. Application of this technique to nanoscale silicon particles has been limited because of the low signal enhancements achieved; it is hypothesized that this is due to the low number of endogenous electronic defects inherent to the particles. We introduce a method of incorporating exogenous radicals into silicon nanoparticle suspensions in order to improve the hyperpolarization of 29Si nuclear spins to levels sufficient for in vivo MR imaging. Calibration of radical concentrations and polarization times are reported for a variety of silicon particle sizes (30−200 nm …


Universality Of Quantum Information In Chaotic Cfts, Nima Lashkari, Anatoly Dymarsky, Hong Liu 2018 Massachusetts Institute of Technology

Universality Of Quantum Information In Chaotic Cfts, Nima Lashkari, Anatoly Dymarsky, Hong Liu

Physics and Astronomy Faculty Publications

We study the Eigenstate Thermalization Hypothesis (ETH) in chaotic conformal field theories (CFTs) of arbitrary dimensions. Assuming local ETH, we compute the reduced density matrix of a ball-shaped subsystem of finite size in the infinite volume limit when the full system is an energy eigenstate. This reduced density matrix is close in trace distance to a density matrix, to which we refer as the ETH density matrix, that is independent of all the details of an eigenstate except its energy and charges under global symmetries. In two dimensions, the ETH density matrix is universal for all theories with the …


Hard-Sphere-Like Dynamics In Highly Concentrated Alpha-Crystallin Suspensions, Preeti Vodnala, Laurence Lurio, Michael C. Vega, Elizabeth Gaillard 2018 Northern Illinois University

Hard-Sphere-Like Dynamics In Highly Concentrated Alpha-Crystallin Suspensions, Preeti Vodnala, Laurence Lurio, Michael C. Vega, Elizabeth Gaillard

Faculty Peer-Reviewed Publications

The dynamics of concentrated suspensions of the eye-lens protein alpha crystallin have been measured using x-ray photon correlation spectroscopy. Measurements were made at wave vectors corresponding to the first peak in the hard-sphere structure factor and volume fractions close to the critical volume fraction for the glass transition. Langevin dynamics simulations were also performed in parallel to the experiments. The intermediate scattering function f(q,τ) could be fit using a stretched exponential decay for both experiments and numerical simulations. The measured relaxation times show good agreement with simulations for polydisperse hard-sphere colloids.


A Machine Learning Algorithm For Identifying And Tracking Bacteria In Three Dimensions Using Digital Holographic Microscopy, Manuel Bedrossian, Marwan El-Kholy, Daniel Neamati, Jay Nadeau 2018 California Institute of Technology

A Machine Learning Algorithm For Identifying And Tracking Bacteria In Three Dimensions Using Digital Holographic Microscopy, Manuel Bedrossian, Marwan El-Kholy, Daniel Neamati, Jay Nadeau

Physics Faculty Publications and Presentations

Digital Holographic Microscopy (DHM) is an emerging technique for three-dimensional imaging of microorganisms due to its high throughput and large depth of field relative to traditional microscopy techniques. While it has shown substantial success for use with eukaryotes, it has proven challenging for bacterial imaging because of low contrast and sources of noise intrinsic to the method (e.g. laser speckle). This paper describes a custom written MATLAB routine using machine-learning algorithms to obtain three-dimensional trajectories of live, lab-grown bacteria as they move within an essentially unrestrained environment with more than 90% precision. A fully annotated version of the software used …


Information Content, Charge Transport Properties, And Computational Capacities Of Proteins, Joseph Murphy Brisendine Jr. 2018 The Graduate Center, City University of New York

Information Content, Charge Transport Properties, And Computational Capacities Of Proteins, Joseph Murphy Brisendine Jr.

Dissertations, Theses, and Capstone Projects

This thesis is the beginning of an attempt to build a coherent theory of the properties of proteins based in information theory and the duality of information theory and nonequilibrium thermodynamics. Throughout, we will adopt the viewpoint that information can act as a thermodynamic potential, which is necessary to understand how biological processes are both enabled and constrained by the laws of thermodynamics. Understanding information as a form of thermodynamic potential also clarifies the description of proteins and other biological macromolecules as “molecular machines”: meso-scale structures with emergent causal powers which perform work on their environments by irreversibly dissipating energy …


Lanthanum-Mediated Dehydrogenation Of Butenes: Spectroscopy And Formation Of La(C4H6) Isomers, Wenjin Cao, Dilkrushi Hewage, Dong-Sheng Yang 2018 University of Kentucky

Lanthanum-Mediated Dehydrogenation Of Butenes: Spectroscopy And Formation Of La(C4H6) Isomers, Wenjin Cao, Dilkrushi Hewage, Dong-Sheng Yang

Chemistry Faculty Publications

La atom reactions with 1-butene, 2-butene, and isobutene are carried out in a laser-vaporization molecular beam source. The three reactions yield the same La-hydrocarbon products from the dehydrogenation and carbon-carbon bond cleavage and coupling of the butenes. The dehydrogenated species La(C4H6) is the major product, which is characterized with mass-analyzed threshold ionization (MATI) spectroscopy and quantum chemical computations. The MATI spectrum of La(C4H6) produced from the La+1-butene reaction exhibits two band systems, whereas the MATI spectra produced from the La+2-butene and isobutene reactions display only a single band system. Each of these …


Detection And Characterization Of The Tin Dihydride (Snh2 And Snd2) Molecule In The Gas Phase, Tony C. Smith, Dennis J. Clouthier 2018 Ideal Vacuum Products, LLC

Detection And Characterization Of The Tin Dihydride (Snh2 And Snd2) Molecule In The Gas Phase, Tony C. Smith, Dennis J. Clouthier

Chemistry Faculty Publications

The SnH2 and SnD2 molecules have been detected for the first time in the gas phase by laser-induced fluorescence (LIF) and emission spectroscopic techniques through the Ã1B1–X̃1A1 electronic transition. These reactive species were prepared in a pulsed electric discharge jet using (CH3)4Sn or SnH4/SnD4 precursors diluted in high pressure argon. Transitions to the electronic excited state of the jet-cooled molecules were probed with LIF, and the ground state energy levels were measured from single rovibronic level emission spectra. The LIF spectrum of SnD2 …


Modulation Of The Navigational Strategy Of Insects In Controlled Temperature Environments, Joseph Shomar, Anggie Ferrer, Josh Forer, Tom Zhang, Mason Klein 2018 University of Miami

Modulation Of The Navigational Strategy Of Insects In Controlled Temperature Environments, Joseph Shomar, Anggie Ferrer, Josh Forer, Tom Zhang, Mason Klein

2018 Entries

With its small size and limited motor tool set, the Drosophila larva is a good system to study how animals alter specific elements of their behavior to search and reach optimal environmental conditions. We aim to understand the larva’s response to temperature across development, in sensory gradients, and to distinguish behavioral modulations based on physical changes from those due to sensory input. PID-controlled instruments drive temporal or spatial temperature gradients; combined with a moat system to replenish gels at high temperature, we can explore the larva’s full behavioral profile. Many larvae are simultaneously observed during free navigation in three different …


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