Physical Sciences and Mathematics Commons^™

Design And Synthesis Of Novel Azasteroids And Pseudoazulenyl Nitrones, Nagaraju Birudukota

FIU Electronic Theses and Dissertations

Steroids are one of the essential classes of bioactive compounds and are involved in many biological functions which include their role as signaling compounds, the alteration of membrane fluidity and the regulation of a variety of metabolic processes. In order to identify novel compounds with beneficial pharmacological action, the synthesis of modified steroids is gaining much attention in recent years. Among those analogs, azasteroids are one of the most important classes which display a variety of biological activities, often free from undesirable side effects. The challenges in the synthesis of steroids, particularly azasteroids, and the potential of azasteroids as novel …

Back To The Future: The Persistence Of Horse Skidding In Large Scale Industrial Community Forests In Chihuahua, Mexico, David Barton Bray, Elvira Duran, Javier Hernández-Salas, Concepción Luján-Alvarez, Miguel Olivas-García, Iván Grijalva-Martínez

Department of Earth and Environment

Horse skidding for extracting logwood is characterized as a niche activity in small-scale forestry, limited to small tracts and low volumes, where environmental impacts and aesthetics are concerned, and to operations with no wood-processing facilities. This article documents and analyzes the widespread persistence, current magnitude, and multiple advantages of horse skidding in large-scale industrial community forest enterprises in Chihuahua, Mexico. We extracted data from the logging permit files of 59 communities in the Sierra Tarahumara and conducted semi-structured interviews with community leaders and foresters in 18 communities, 17 random selections, and one purposefully selected case. There are nine communities that …

Aqua­Bis­(2,2'-Bi­Pyridine-[Kappa]2n,N')Chlorido­Nickel(Ii) Chloride Chloro­Form Monosolvate Hemihydrate, Eugenia Vasileiadou, Panagiotis A. Angaridis, Raphael G. Raptis, Logesh Mathivathanan

Department of Chemistry and Biochemistry

The title solvated salt, [NiCl(C₁₀H₈N₂)₂(H₂O)]Cl·CHCl₃·0.5H₂O, contains a mononuclear Ni^II complex cation with 2,2'-bi­pyridine, chloride and aqua ligands forming a slightly distorted ClN₄O octa­hedral coordination set. The charge of the cation is balanced by a chloride anion. In the crystal, half a water mol­ecule and a chloro­form solvent mol­ecule are present per formula unit. Individual components are held together by O-HCl hydrogen bonding and - inter­actions.

Going Beyond The Analysis Of Common Contaminants: Target, Suspect, And Non-Target Analysis Of Complex Environmental Matrices By High-Resolution Mass Spectrometry, Anna Katarina Huba

FIU Electronic Theses and Dissertations

The advancements in the field of analytical chemistry, and especially mass spectrometry, have been redefining the field of contaminant detection. While more traditional analysis was sufficient to screen for a small number of well-known compounds, new techniques such as high-resolution mass spectrometry, have enabled a fairly comprehensive screening for previously unknown contaminants. This is enormously beneficial with respect to the analysis of water, air, or soil quality in a society that continuously introduces novel anthropogenic compounds into the environment. This dissertation, thus, focused on the analysis of the uncharacterized portion of compounds in two types of complex environmental matrices (i.e., …

Carbon Nanotube- And Gold Nanoparticle-Based Materials For Electrochemical And Colorimetric Sensing Applications, Janak Paudyal 9255967

FIU Electronic Theses and Dissertations

Carbon nanotubes (CNTs) and gold nanoparticles (AuNPs) are widely used for sensing applications due to their distinctive electrical and optical properties, and we have explored the development of methods that enable the incorporation of these nanomaterials into new and improved sensing devices.

As a means for fabricating simple, low-cost and fast detection platforms for various applications, we have developed paper-based electrochemical detection platforms based on CNTs or platinum nanoparticle (PtNP)-CNT composite materials. We describe the use of a paper-based, low density, a three-dimensional thin film of interconnected CNTs as an electrode material. We studied the electrochemical properties of these paper-based …

Synthesis And Characterization Of A Hydrolytically Stable Photochromic Copolymer Containing An N-Alkylindolylfulgimide, Samina Yasmeen

FIU Electronic Theses and Dissertations

Fulgides and fulgimides comprise one class of thermally irreversible photochromic organic compounds. Light dependent isomerization, has made these organic molecules promising materials for several applications, including optical memory devices, and switches. Hydrolytic stability of fulgides and fulgimides is crucial for their practical applications in biological systems and humid environments. Fulgimides, the most important derivative of fulgides, have a succinimide ring, which, unlike the anhydride ring, of fulgides, is resistant to hydrolytic degradation. A novel N-alkylindolylfulgimide was synthesized and copolymerized with acrylamide. The photochromic and hydrolytic properties of the copolymer in phosphate (pH 7.4) and acetate (pH 5.0) buffer solutions …

H I Structure And Kinematics Of The Interstellar Medium In The Little Things Galaxies, Nau R. Pokhrel

FIU Electronic Theses and Dissertations

We present a catalog of the neutral atomic hydrogen structures (H I holes) and the analysis of their properties in nearby (≤ 10.3 Mpc) gas-rich dwarf galaxies of the LITTLE THINGS (Local Irregulars That Trace Luminosity Extremes, The H I Nearby Galaxy Survey) group. We used high sensitivity (≤ 1.1 mJy beam^-1 channel^-1), high velocity resolution (1.3 km s^-1 to 2.6 km s^-1) and high linear resolution (average ~110 pc; angular resolution ~6”) H I data of 37 dwarf irregulars and four blue compact dwarf galaxies. We cataloged H I holes in the entire …

Large Scale Data Mining For It Service Management, Chunqiu Zeng

FIU Electronic Theses and Dissertations

More than ever, businesses heavily rely on IT service delivery to meet their current and frequently changing business requirements. Optimizing the quality of service delivery improves customer satisfaction and continues to be a critical driver for business growth. The routine maintenance procedure plays a key function in IT service management, which typically involves problem detection, determination and resolution for the service infrastructure.

Many IT Service Providers adopt partial automation for incident diagnosis and resolution where the operation of the system administrators and automation operation are intertwined. Often the system administrators' roles are limited to helping triage tickets to the processing …

Mercury Sulfide Dissolution In Environmental Conditions: Thermodynamic And Kinetic Approaches, Ping Jiang

FIU Electronic Theses and Dissertations

Mercury (Hg) is a global contaminant of ecosystems and human health risk, with complicated biogeochemical processes. Mercury sulfide (HgS) dissolution has been suggested as a key process in Hg cycling, as it could potentially increase the pool of inorganic Hg (iHg) for the production of methylmercury (MeHg). Despite previous sporadic observations of enhanced HgS dissolution under certain conditions, much remains unclear on mechanisms of HgS dissolution. The objective of my research was to advance the mechanistic understanding of HgS dissolution, concerning re-adsorption of released Hg, effects of thiol-ligands, and Hg speciation.

Considering the lack of feasible techniques to differentiate dissolution …

Kinetics And Reaction Mechanisms For Methylidyne Radical Reactions With Small Hydrocarbons, Joao Marcelo Lamim Ribeiro

FIU Electronic Theses and Dissertations

The chemical evolution with respect to time of complex macroscopic mixtures such as interstellar clouds and Titan’s atmosphere is governed via a mutual competition between thousands of simultaneous processes, including thousands of chemical reactions. Chemical kinetic modeling, which attempts to understand their macroscopic observables as well as their overall reaction mechanism through a detailed understanding of their microscopic reactions and processes, thus require thousands of rate coefficients and product distributions. At present, however, just a small fraction of these have been well-studied and measured; in addition, at the relevant low temperatures, such information becomes even more scarce. Due to the …

The Impacts Of Telecommuting On The Time-Space Distribution Of Daily Activities, Mario Benito Rojas Iv

FIU Electronic Theses and Dissertations

As major cities have aged, they have also met or exceeded their transportation infrastructure’s capacity. This has led to many negative impacts such as increased greenhouse gas emissions, delay, travel time, congestion, as well as decreased energy independence, standard of living for the cities’ inhabitants and the world as a whole. As a result, these cities will undoubtedly suffer and will struggle to meet the needs of their citizens. It is becoming more evident, and relevant, that the solution to today’s and tomorrow’s transportation problems will be overcome through the use of policy as well as innovative strategies, one of …

Carotenoids And Fatty Acids In Early Lactation: A Study Of A Peruvian Population, Vanesa Mendez

FIU Electronic Theses and Dissertations

Lipid soluble carotenoids are micronutrients present in human milk that serve as precursors of vitamin A and also play an important role protecting cells from damage arising from photooxidative processes and reactive oxygen species. Fatty acids comprise about 3-5% of human milk and are mainly present as triglycerides. They are a major energy source for the infant and are necessary to support cell growth required for normal development and maturation of critical organs. Transport of carotenoids into milk has been little studied and there has been no previous investigation of the relationship of carotenoid transport with that of individual fatty …

The Optimization Of Pressure Cycling Technology (Pct) For Differential Extraction Of Sexual Assault Casework, Vanessa Martinez

FIU Electronic Theses and Dissertations

A two-step protocol has been devised as a rapid and selective alternative to conventional differential extraction techniques with an increased recovery of DNA. The protocol involves pressure cycling with the Barocycler^® NEP 2320 from Pressure Biosciences. Inc. in alkaline conditions for epithelial cell lysis and removal. This step is followed by alkaline lysis at 95^º C for extraction of sperm cell DNA. At 1:1 or 2:1 female to male cell ratios, high selectivity and complete separation can be achieved. But at higher ratios, male allelic dropout is observed. This protocol has been modified to generate a clean male …

Two Dimensional Lattice Gauge Theory With And Without Fermion Content, Dibakar Sigdel

FIU Electronic Theses and Dissertations

Quantum Chromo Dynamics (QCD) is a relativistic field theory of a non-abelian gauge field coupled to several flavors of fermions. Two dimensional (one space and one time) QCD serves as an interesting toy model that shares several features with the four dimensional physically relevant theory. The main aim of the research is to study two dimensional QCD using the lattice regularization.

Two dimensional QCD without any fermion content is solved analytically using lattice regularization. Explicit expressions for the expectation values of Wilson loops and the correlation of two Polyakov loops oriented in two different directions are obtained. Physics of the …

Biogeographical Patterns Of Soil Microbial Communities: Ecological, Structural, And Functional Diversity And Their Application To Soil Provenance, Natalie Damaso

FIU Electronic Theses and Dissertations

The current ecological hypothesis states that the soil type (e.g., chemical and physical properties) determines which microbes occupy a particular soil and provides the foundation for soil provenance studies. As human profiles are used to determine a match between evidence from a crime scene and a suspect, a soil microbial profile can be used to determine a match between soil found on the suspect’s shoes or clothing to the soil at a crime scene. However, for a robust tool to be applied in forensic application, an understanding of the uncertainty associated with any comparisons and the parameters that can significantly …

A Carbon And Oxygen Stable Isotope-Dendrochronology Study Of Trees From South Florida: Implications For The Development Of A High-Resolution Subtropical Paleoclimate Record, Carrie E. Rebenack

FIU Electronic Theses and Dissertations

The global paleoclimate archive is lacking in tropical dendrochronology studies as a result of limitations from inconsistent tree-ring production imposed by precipitation-driven seasonality. The slash pine, Pinus elliottii Engelm. var. densa, is the dominant canopy species of Big Pine Key (BPK) rocklands and has been shown to produce complicated, but distinct, ring structures; however, traditional dendrochronology studies have not established correlations between ring width measurements and major climate drivers controlling South Florida precipitation. My study utilized the carbon (δ¹³C) and oxygen (δ¹⁸O) isotope records in the α-cellulose component of tree-rings to extract information about the …

Qualitative Analysis For The Characterization And Discrimination Of Printing Inks, Rhett J. Williamson

FIU Electronic Theses and Dissertations

Improvements in printing technology and the wide accessibility of advanced printers has resulted in an increase in counterfeiting. Of particular interest to forensic document examiners, ink analysis of security documents has emerged as an important tool for the analysis, comparison, and association of inks to a potential production source. In this study, methods were developed for Py-GC/MS, ATR-FTIR, DART-MS, and MALDI-MS analyses of printing inks of four classes: 78 inkjet inks, 76 toners, 79 offset inks, and 86 intaglio inks in order to generate information on the organic chemical characterization of the inks to determine the ability to associate and …

Developing Benthic Class Specific, Chlorophyll-A Retrieving Algorithms For Optically-Shallowwater Using Seawifs, Tara Blakey, Assefa M. Melesse, Michael C. Sukop, Georgio Tachiev, Dean Whitman, Fernando Miralles-Wilhelm

Department of Earth and Environment

This study evaluated the ability to improve Sea-Viewing Wide Field-of-View Sensor (SeaWiFS) chl-a retrieval from optically shallow coastal waters by applying algorithms specific to the pixels’ benthic class. The form of the Ocean Color (OC) algorithm was assumed for this study. The operational atmospheric correction producing Level 2 SeaWiFS data was retained since the focus of this study was on establishing the benefit from the alternative specification of the bio-optical algorithm. Benthic class was determined through satellite image-based classification methods. Accuracy of the chl-a algorithms evaluated was determined through comparison with coincident in situ measurements of chl-a. The regionally-tuned …

Role Of Students’ Participation On Learning Physics In Active Learning Classes, Binod Nainabasti

FIU Electronic Theses and Dissertations

Students’ interactions can be an influential component of students’ success in an interactive learning environment. From a participation perspective, learning is viewed in terms of how students transform their participation. However, many of the seminal papers discussing the participationist framework are vague on specific details about what student participation really looks like on a fine-grained scale. As part of a large project to understand the role of student participation in learning, this study gathered data that quantified students’ participation in three broad areas of two student-centered introductory calculus-based physics classes structured around the Investigative Science Learning Environment (ISLE) philosophy. These …

A Search For Qpos In The Blazar Oj287: Preliminary Results From The 2015/2016 Observing Campaign, James R. Webb

Department of Physics

No abstract provided.

Multi-Frequency Blazar Micro-Variability As A Tool To Investigate Relativistic Jets, James R. Webb

Department of Physics

For the past 12 years we have been studying optical micro-variability of a sample of 15 Blazars. We summarize the results of this study and draw some basic conclusions about the characteristics of micro-variability. The intermittency, the stochastic nature, and the similar profile shapes seen in micro-variations at different times and in different objects have led us to a possible model to explain the observed micro-variations. The model is based on a strong shock propagating down a relativistic jet and encountering turbulence which causes density or magnetic field enhancements. We use the theory of Kirk, Reiger, and Mastichiadis (1998) to …

On Some Test Statistics For Testing The Population Skewness And Kurtosis: An Empirical Study, Yawen Guo

FIU Electronic Theses and Dissertations

The purpose of this thesis is to propose some test statistics for testing the skewness and kurtosis parameters of a distribution, not limited to a normal distribution. Since a theoretical comparison is not possible, a simulation study has been conducted to compare the performance of the test statistics. We have compared both parametric methods (classical method with normality assumption) and non-parametric methods (bootstrap in Bias Corrected Standard Method, Efron’s Percentile Method, Hall’s Percentile Method and Bias Corrected Percentile Method). Our simulation results for testing the skewness parameter indicate that the power of the tests differs significantly across sample sizes, the …

A Comprehensive Review On Water Quality Parameters Estimation Using Remote Sensing Techniques, Mohammad Hajigholizadeh, Assefa M. Melesse, Lakshmi Reddi

Department of Earth and Environment

Remotely sensed data can reinforce the abilities of water resources researchers and decision makers to monitor waterbodies more effectively. Remote sensing techniques have been widely used to measure the qualitative parameters of waterbodies (i.e., suspended sediments, colored dissolved organic matter (CDOM), chlorophyll-a, and pollutants). A large number of different sensors on board various satellites and other platforms, such as airplanes, are currently used to measure the amount of radiation at different wavelengths reflected from the water’s surface. In this review paper, various properties (spectral, spatial and temporal, etc.) of the more commonly employed spaceborne and airborne sensors are …

Synthetic Studies Toward A Novel Hydroxylamine Of Potential Utility In The Preparation Of Mitochondriotropic Nitrones, Gloria Patricia Perez

FIU Electronic Theses and Dissertations

Mitochondrial dysfunction and oxidative stress have been linked with many pathological conditions. Studies suggest that antioxidants able to accumulate in the inner regions of the mitochondria as well as possessing the chemical entities to cross membranes such as the blood brain barrier, could potentially overcome many of the limitations found with current antioxidants.

Nitrones have demonstrated great antioxidant potential due to their free radical scavenging properties, cardio and neuro-protective activities. In this research, several synthetic studies were performed with the aim of synthesizing a novel hydroxylamine of potential utility for the preparation of mitochondria targeted nitrones. These studies resulted in …

How The Proximal Pocket May Influence The Enantiospecificities Of Chloroperoxidase-Catalyzed Epoxidations Of Olefins, Alexander N. Morozov, David C. Chatfield

Department of Chemistry and Biochemistry

Chloroperoxidase-catalyzed enantiospecific epoxidations of olefins are of significant biotechnological interest. Typical enantiomeric excesses are in the range of 66%–97% and translate into free energy differences on the order of 1 kcal/mol. These differences are generally attributed to the effect of the distal pocket. In this paper, we show that the influence of the proximal pocket on the electron transfer mechanism in the rate-limiting event may be just as significant for a quantitatively accurate account of the experimentally-measured enantiospecificities.

Qualitative Detection Of Selected Designer Drugs And Relevant Metabolites In Environmental Water Samples, Marley Pruyn

FIU Electronic Theses and Dissertations

Designer drugs are compounds which have been synthetically derived from illicit drugs. After consumption, drugs and their metabolites are introduced into the sewage water which is treated and disposed into the environment. A combined target, suspect and non-target workflow was created to detect designer drugs in environmental water samples. Multiple water samples were spiked with an unknown mixture of drugs and metabolites to assess the efficiency of the method. Samples were collected from sewage influent and effluent pipes, downstream from a sewage outfall and reclaimed water. Analysis was conducted with high resolution MS using the QExactive Orbitrap. Screening was performed …

Di-Μ-Bromido-Bis­­[Bromido­(4,4′-Dihy­Dr­Oxy-2,2′-Bi­Pyridine-Κ2n,N′)Copper(Ii)], Alan J. Rodriguez-Santiago, Carlos Acosta, Raphael G. Raptis

Department of Chemistry and Biochemistry

The mol­ecules of the title compound, [Cu₂Br₄(C₁₀H₈N₂O₂)₂], are centrosymmetric dimers. The Cu^II atom exhibits a distorted square-pyramidal coordination geometry, with two bridging bromide ligands and the N atoms of the 4,4′-dihy­droxy-2,2′-bi­pyridine chelate in the equatorial plane. π–π stacking and hydrogen-bonding inter­actions of the O—H⋯Br, C—H⋯·Br and C—H⋯O types consolidate the crystal packing.

Dna Aptamer Confirmation And Utilization For The Cyanotoxin, Cylindrospermopsin, Diane M. Catlin

FIU Electronic Theses and Dissertations

Cyanotoxins are posing an increasing threat to the health of humans and wildlife. Cylindrospermopsin is a cyanotoxin that occurs in warm climates and is harmful when ingested. The toxic effects of CYN can affect multiple organ systems. The effects, coupled with the evidence of a mass contamination of a water supply in Australia, prove that CYN needs to be investigated further.

Aptamers have become a desirable method for detection of CYN as a result of an aptamer’s high specificity and the ability to scale up experiments. Aptamers have been designed to bind with a variety of targets, including cyanotoxins. An …

Deploying A Cms Tier-3 Computing Cluster With Grid-Enabled Computing Infrastructure, Sean Stewart

FIU Electronic Theses and Dissertations

The Large Hadron Collider (LHC), whose experiments include the Compact Muon Solenoid (CMS), produces over 30 million gigabytes of data annually, and implements a distributed computing architecture—a tiered hierarchy, from Tier-0 through Tier-3—in order to process and store all of this data. Out of all of the computing tiers, Tier-3 clusters allow scientists the most freedom and flexibility to perform their analyses of LHC data. Tier-3 clusters also provide local services such as login and storage services, provide a means to locally host and analyze LHC data, and allow both remote and local users to submit grid-based jobs. Using the …

Community-Governed Multifunctional Landscapes And Forest Conservation In The Sierra Norte Of Oaxaca, Mexico, Barbara Pazos Almada

FIU Electronic Theses and Dissertations

Community forestry is an evolving approach to forest management, shown to maintain forest cover, while generating income for local communities. In Sierra Norte (SN), a region with no public protected areas, indigenous communities have been actively conserving their forests for decades, through conservation zoning and careful management of their logging areas. This study found that across 22 communities in SN, an estimated 2,949,116.50 m³ of timber were produced from 1993 to 2013, while the region maintains 78% forest cover. About 75% of the forest is under some form of community conservation. Community governance plays a major role, as rules …