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Florida International University

FIU Electronic Theses and Dissertations

2010

Articles 1 - 9 of 9

Full-Text Articles in Physical Sciences and Mathematics

Development Of A Dynamic Headspace Concentration Technique For The Non-Contact Sampling Of Human Odor Samples And The Creation Of Canine Training Aids, Lauryn E. Degreeff Nov 2010

Development Of A Dynamic Headspace Concentration Technique For The Non-Contact Sampling Of Human Odor Samples And The Creation Of Canine Training Aids, Lauryn E. Degreeff

FIU Electronic Theses and Dissertations

Human scent and human remains detection canines are used to locate living or deceased humans under many circumstances. Human scent canines locate individual humans on the basis of their unique scent profile, while human remains detection canines locate the general scent of decomposing human remains. Scent evidence is often collected by law enforcement agencies using a Scent Transfer Unit, a dynamic headspace concentration device. The goals of this research were to evaluate the STU-100 for the collection of human scent samples, and to apply this method to the collection of living and deceased human samples, and to the creation of …

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Biomimetic Modeling Of The Nitrogen-Centered Radical Postulated To Occur During The Inhibition Of Ribonucleotide Reductases By 2'-Azido-2'-Deoxynucleotides., Thao P. Dang Nov 2010

Biomimetic Modeling Of The Nitrogen-Centered Radical Postulated To Occur During The Inhibition Of Ribonucleotide Reductases By 2'-Azido-2'-Deoxynucleotides., Thao P. Dang

FIU Electronic Theses and Dissertations

Ribonucleotide reductases (RNR) are essential enzymes that catalyze the reduction of ribonucleotides to 2'-deoxyribonucleotides, which is a critical step that produces precursors for DNA replication and repair. The inactivation of RNR, logically, would discontinue producing the precursors of the DNA of viral or cancer cells, which then would consequently end the cycle of DNA replication. Among different compounds that were found to be inhibitors of RNR, 2'-azido-2'-deoxynucleotide diphosphates (N3NDPs) have been investigated in depth as potent inhibitors of RNR. Decades of investigation has suggested that the inactivation of RNR by N3NDPs is a result of the formation of a nitrogen-centered …

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An Economic Valuation Analysis Of Buccoo Reef Marine Park, Tobago, West Indies, Dionne J. Da Costa Nov 2010

An Economic Valuation Analysis Of Buccoo Reef Marine Park, Tobago, West Indies, Dionne J. Da Costa

FIU Electronic Theses and Dissertations

The purpose of this study was to evaluate tourism capacity, the effectiveness of the management plan and the visitors’ willingness to pay (WTP) for increased conservation effort in the Buccoo Reef Marine Park (BRMP) in Tobago. Non-market contingent valuation was applied to estimate tourists’ WTP, using the data from a survey of 164 tourists. Local residents and government agencies were consulted to evaluate the management plan and the tourism capacity. Eighty-eight percent of local residents stated that the park was not well managed and that they lacked trust in the park agency. The density of tourists was 67-97% more than …

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Assessment Of Submerged Vegetation As Indicators Of Irgarol Contamination, Melissa V. Fernandez Sep 2010

Assessment Of Submerged Vegetation As Indicators Of Irgarol Contamination, Melissa V. Fernandez

FIU Electronic Theses and Dissertations

Irgarol 1051 is a common antifoulant toxic to certain marine organisms. Submerged aquatic vegetation (SAV) are exposed to this herbicide when it leaches into the marine environment from painted structures, making SAVs ideal candidates to function as sentinel indicator of contamination. In the initial stage of this study, Coconut Grove and Key Largo Harbor were assessed for environmental exposure to Irgarol. Water, sediment and SAVs were collected, the latter two subject to automated solid phase extraction, and all samples analyzed by GC/MS-SIM for Irgarol and its metabolite, M1. Of the vegetation analyzed, Halodule and Syringodium had the highest capacity to …

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Developing Of Germyldesulonylation And Thiodesulfonylation Reactions For The Synthesis Of Novel Nucleoside Analogues. Efficient Synthesis Of Novel (Α-Fluoro)Vinyl Sulfides, Pablo R. Sacasa Jr Jul 2010

Developing Of Germyldesulonylation And Thiodesulfonylation Reactions For The Synthesis Of Novel Nucleoside Analogues. Efficient Synthesis Of Novel (Α-Fluoro)Vinyl Sulfides, Pablo R. Sacasa Jr

FIU Electronic Theses and Dissertations

S-adenosyl-L-homocysteine (AdoHcy) hydrolase effects hydrolytic cleavage of AdoHcy to produce both adenosine and L-homocysteine and is a feedback inhibitor of S-adenosyl-L-methionine (SAM). Nucleoside analogues bearing an alkenyl or fluoroalkenyl chain between sulfur and C5′ utilizing Negishi coupling reactions were synthesized. Palladium-catalyzed cross-coupling between the 5′-deoxy-5′-(iodomethylene) nucleosides and alkylzinc bromides gives analogues with the alkenyl unit. Palladium-catalyzed selective monoalkylation of 5′-(bromofluoromethylene)-5′-deoxy-adenosine with alkylzinc bromide afford adenosylhomocysteine analogues with a 6′-(fluoro)vinyl motif. The vinylic adenine nucleosides produced time-dependent inactivation of the S-adenosyl-L-homocysteine hydrolases. Stannydesulfonylation reaction is a critical step in the synthesis of E-fluorovinyl cytidine (Tezacitabine) a ribonucleoside reductase inhibitor with a …

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Conformational Dynamics Associated With Calcium Binding To Calcium Transducers, Gangadhar Dhulipala Jul 2010

Conformational Dynamics Associated With Calcium Binding To Calcium Transducers, Gangadhar Dhulipala

FIU Electronic Theses and Dissertations

The Ca2+ association to calcium binding proteins (CaBPs) represents an essential step in Ca2+ signal transduction. This study presents a characterization of Ca interactions with two CaBPs, calmodulin and DREAM, using time-resolved photothermal and fluorescence techniques. Calcium binding to the calmodulin C-terminal domain is associated with a volume change of 40 mL mol-1and an enthalpy change of 35 ± 16 kcal mol-1. These parameters are consistent with the Ca2+ triggered exposure of hydrophobic patches on the calmodulin surface. Also, the rate limiting step for Ca2+ binding to calmodulin is the closed-to-open transition …

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Structural Characterization Of Metal Hydrides For Energy Applications, Lyci George May 2010

Structural Characterization Of Metal Hydrides For Energy Applications, Lyci George

FIU Electronic Theses and Dissertations

Hydrogen can be an unlimited source of clean energy for future because of its very high energy density compared to the conventional fuels like gasoline. An efficient and safer way of storing hydrogen is in metals and alloys as hydrides. Light metal hydrides, alanates and borohydrides have very good hydrogen storage capacity, but high operation temperatures hinder their application. Improvement of thermodynamic properties of these hydrides is important for their commercial use as a source of energy. Application of pressure on materials can have influence on their properties favoring hydrogen storage. Hydrogen desorption in many complex hydrides occurs above the …

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A Generalized Multidimensional Index Structure For Multimedia Data To Support Content-Based Similarity Searches In A Collaborative Search Environment, Kasturi Chatterjee Mar 2010

A Generalized Multidimensional Index Structure For Multimedia Data To Support Content-Based Similarity Searches In A Collaborative Search Environment, Kasturi Chatterjee

FIU Electronic Theses and Dissertations

Since multimedia data, such as images and videos, are way more expressive and informative than ordinary text-based data, people find it more attractive to communicate and express with them. Additionally, with the rising popularity of social networking tools such as Facebook and Twitter, multimedia information retrieval can no longer be considered a solitary task. Rather, people constantly collaborate with one another while searching and retrieving information. But the very cause of the popularity of multimedia data, the huge and different types of information a single data object can carry, makes their management a challenging task. Multimedia data is commonly represented …

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The Construction And Optimization On An Ion Mobility Spectrometer For The Analysis Of Explosives And Drugs, Hanh Tuyet Lai Feb 2010

The Construction And Optimization On An Ion Mobility Spectrometer For The Analysis Of Explosives And Drugs, Hanh Tuyet Lai

FIU Electronic Theses and Dissertations

Today, over 15,000 Ion Mobility Spectrometry (IMS) analyzers are employed at worldwide security checkpoints to detect explosives and illicit drugs. Current portal IMS instruments and other electronic nose technologies detect explosives and drugs by analyzing samples containing the headspace air and loose particles residing on a surface. Canines can outperform these systems at sampling and detecting the low vapor pressure explosives and drugs, such as RDX, PETN, cocaine, and MDMA, because these biological detectors target the volatile signature compounds available in the headspace rather than the non-volatile parent compounds of explosives and drugs. In this dissertation research volatile signature compounds …

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