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- Title
- Deciphering the Role of Adrenergic Hormones in Embryonic Cardiac Calcium Signaling and Metabolism.
- Creator
-
Peoples, Jessica, Ebert, Steven, Davidson, Victor, Phanstiel, Otto, Yooseph, Shibu, University of Central Florida
- Abstract / Description
-
The adrenergic hormones norepinephrine (NE) and epinephrine (EPI) are critical regulators of mammalian cardiovascular physiology. NE and EPI mediate stress responses to enhance cardiovascular function, however dysregulation of adrenergic signaling leads to heart failure, congenital heart malformations, and sudden cardiac death. Adrenergic hormone-expressing cells were found in the early embryonic heart, and NE has been determined essential for embryonic cardiac development. Despite extensive...
Show moreThe adrenergic hormones norepinephrine (NE) and epinephrine (EPI) are critical regulators of mammalian cardiovascular physiology. NE and EPI mediate stress responses to enhance cardiovascular function, however dysregulation of adrenergic signaling leads to heart failure, congenital heart malformations, and sudden cardiac death. Adrenergic hormone-expressing cells were found in the early embryonic heart, and NE has been determined essential for embryonic cardiac development. Despite extensive work in adults, the regulatory roles and adrenergic targets of these hormones during embryonic cardiac development have not yet been fully determined. Prior transcriptomic studies from our lab showed that expression of signal transduction and metabolic genes in embryos lacking adrenergic hormones were by far the most affected categories of genes. Thus, we hypothesized that adrenergic hormones stimulate early calcium signaling, and are required for sufficient supply of energy substrates for the metabolic shift from anaerobic glycolysis to aerobic respiration during heart development. We utilized the dopamine ?-hydroxylase knock-out (Dbh-/-) mouse model to examine effects of adrenergic-deficiency on calcium signaling and metabolism during heart development. Using calcium-imaging and patch-clamp techniques, we found that calcium transients, voltage-gated calcium channels, and L-type calcium currents in adrenergic-deficient embryonic hearts were not affected relative to controls indicating adrenergic stimulation did not influence early calcium signaling. Metabolomics analyses of adrenergic-deficient hearts revealed disruption in glycolytic and pentose-phosphate pathways as well as reduced activity of respective regulatory enzymes, glyceraldehyde 3-phosphate dehydrogenase and glucose 6-phosphate dehydrogenase indicating compromised glucose metabolism. Addition of pyruvate to embryonic hearts led to significant recovery of ATP concentrations and oxygen consumption rates, thereby supporting the hypothesis that adrenergic-deficient hearts are (")starved(") of metabolic substrates required for transitions from anaerobic glycolysis to aerobic metabolism. Overall, we showed that adrenergic hormones are not necessary for calcium signaling in the embryonic heart, but are essential regulators ensuring sufficient metabolic substrate and boosting enzymatic activities to fuel aerobic metabolism.
Show less - Date Issued
- 2018
- Identifier
- CFE0007233, ucf:52223
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007233
- Title
- Ethnic Exclusion (&) Conflict in the Caspian: Comparing Kazakhstan (&) Azerbaijan.
- Creator
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Krikorian, Danny, Sadri, Houman, Mousseau, Demet, Marien, Daniel, University of Central Florida
- Abstract / Description
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Political science explains various motives for political violence. This research focuses on a particular kind of motivation: ethnicity. The 20th century has seen many instances of ethnic violence, and this research seeks to understand why it occurs in one place and time and not the other. Traditionally the literature on ethnic violence reflects on economic conditions, regime type, geopolitics and historical context as significant variables. This research posits that Kazakhstan managed to...
Show morePolitical science explains various motives for political violence. This research focuses on a particular kind of motivation: ethnicity. The 20th century has seen many instances of ethnic violence, and this research seeks to understand why it occurs in one place and time and not the other. Traditionally the literature on ethnic violence reflects on economic conditions, regime type, geopolitics and historical context as significant variables. This research posits that Kazakhstan managed to avoid ethnic violence because it is more politically developed. The existence of an accommodative legislative assembly, which assures the rights of ethnic minorities, is an example of Kazakhstan's model of ethnic inclusiveness and harmony. Such mechanisms are wholly absent in Azerbaijan, despite immense oil wealth; it exhibits cases of extreme ethnic violence, terrorist mobilization and threats to regime survival. Relatively politically developed states like Kazakhstan are more inclined towards ethnic tolerance, inclusion (&) harmony, while underdeveloped states lack the apparatus' therein, resulting in exclusion and conflict. The main implication of the research is that neither territorial disputes, nor resource curse nor post-Soviet disintegration help to explain why ethnic conflict happens in one place, Azerbaijan, and not in the other, Kazakhstan. There is however a positive relationship between ethnic inclusion (&) ethnic harmony.
Show less - Date Issued
- 2018
- Identifier
- CFE0007213, ucf:52227
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007213
- Title
- Mechanical and physical characteristics of knee flexors and extensors following different warm up protocols in collegiate male soccer athletes.
- Creator
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Redd, Mike, Fukuda, David, Stout, Jeffrey, Garcia, Jeanette, Wells, Adam, Stock, Matt, University of Central Florida
- Abstract / Description
-
PURPOSE: To compare potential differences in mechanical and physical characteristics of knee flexors and extensors in collegiate male soccer players following different warm up protocols.METHODS: Sixteen collegiate male soccer players (20.33 (&)#177; 1.33 years, 176.97 (&)#177; 6.72 cm, and 78.43 (&)#177; 7.42 kg) participated in this study. A small sided games warm up (SSG), a dynamic warm up (DYN), and a plyometric warm up (PLY) were completed using a randomized crossover design....
Show morePURPOSE: To compare potential differences in mechanical and physical characteristics of knee flexors and extensors in collegiate male soccer players following different warm up protocols.METHODS: Sixteen collegiate male soccer players (20.33 (&)#177; 1.33 years, 176.97 (&)#177; 6.72 cm, and 78.43 (&)#177; 7.42 kg) participated in this study. A small sided games warm up (SSG), a dynamic warm up (DYN), and a plyometric warm up (PLY) were completed using a randomized crossover design. Tensiomyography (TMG) was used to assess contraction time (Tc), delay time (Td) and maximal displacement (Dm) of the rectus femoris (RF) and biceps femoris (BF) of both legs before (PRE) and after (POST) each warm up. POST assessment included: TMG of the RF and BF, countermovement jump height (CMJ-h), CMJ flight time (CMJ-ft), 20m sprint time (20m), T-test time, and sit and reach (SR) distance. All TMG measures were analyzed using a three-way [condition (&)#215; time x leg] analysis of variance (ANOVA). All performance variable data were analyzed with a repeated measures ANOVA.RESULTS: There was no difference between warm up protocols for T-test, CMJ-h, or CMJ-ft. 20m significantly improved following SSG (p=0.020) compared to DYN and PLY. SR was significantly greater following PLY (p=0.022). Three-way ANOVA did not reveal a significant interaction for any of the measured TMG variables. However, main effects of time were seen PRE to POST for BF-Tc (p=0.035), RF-Td (p(<)0.001) and BF-Td, (p=0.008) and a main effect of condition was seen for RF-Tc (p=0.038).CONCLUSION: Warm-up specific improvements were demonstrated in sprint speed and flexibility measures following SSG and PLY, respectively. While no differences were shown between the examined protocols, the present study revealed PRE to POST changes in certain TMG measures (RF-Td, BF-Td, and BF-Tc) following a warm up in male collegiate soccer athletes.
Show less - Date Issued
- 2018
- Identifier
- CFE0007240, ucf:52224
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007240
- Title
- Power Scaling of High Power Solid State Lasers.
- Creator
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Oh, Bumjin, Richardson, Martin, Soileau, MJ, Chini, Michael, University of Central Florida
- Abstract / Description
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The solid-state laser is one of the most widely used lasers in scientific research and industrial applications. This thesis describes detailed investigations of two modern architectures of high power cw solid-state lasers, a 20 W diode-pumped Yb:YAG thin disc laser and 300 W diode-pumped Nd:YAG rod laser. With the thin disc laser architecture, the signal beam must fit to the pump area on the disc defined by the multi-pass diode pump configuration. The beam propagation, beam diameter, phase...
Show moreThe solid-state laser is one of the most widely used lasers in scientific research and industrial applications. This thesis describes detailed investigations of two modern architectures of high power cw solid-state lasers, a 20 W diode-pumped Yb:YAG thin disc laser and 300 W diode-pumped Nd:YAG rod laser. With the thin disc laser architecture, the signal beam must fit to the pump area on the disc defined by the multi-pass diode pump configuration. The beam propagation, beam diameter, phase and thermal effects for various cavity configurations are investigated theoretically and experimentally. In addition, the internal loss, small signal gain, and thermal lensing effect are essential properties to construct the laser system but usually unknown. The theories and methodologies to obtain these properties are presented and the experimental results are compared. In a second phase of the project, the multi-mode and single-mode operation of a high power diode-pumped rod laser system are examined and compared to the thin disc system. Thermal effects on the phase, beam quality and brightness are examined and future applications and improvements considered.
Show less - Date Issued
- 2018
- Identifier
- CFE0007232, ucf:52221
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007232
- Title
- Equivalency Analysis of Sidestick Controller Modes During Manual Flight.
- Creator
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Rummel, Alex, Karwowski, Waldemar, Elshennawy, Ahmad, Hancock, Peter, University of Central Florida
- Abstract / Description
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Equivalency analysis is a statistical procedure that can enhance the findings of an analysis of variance in the case when non-significant differences are identified. The demonstration of functional equivalence or the absence of practical differences is useful to designers introducing new technologies to the flight deck. Proving functional equivalence is an effective means to justify the implementation of new technologies that must be (")the same or better(") than previous technology. This...
Show moreEquivalency analysis is a statistical procedure that can enhance the findings of an analysis of variance in the case when non-significant differences are identified. The demonstration of functional equivalence or the absence of practical differences is useful to designers introducing new technologies to the flight deck. Proving functional equivalence is an effective means to justify the implementation of new technologies that must be (")the same or better(") than previous technology. This study examines the functional equivalency of three operational modes of a new active control sidestick during normal operations while performing manual piloting tasks. Data from a between-subjects, repeated-measures simulator test was analyzed using analysis of variance and equivalency analysis. Ten pilots participated in the simulator test which was conducted in a fixed-base, business jet simulator. Pilots performed maneuvers such as climbing and descending turns and ILS approaches using three sidestick modes: active, unlinked, and passive. RMS error for airspeed, flight path angle, and bank angle were measured in addition to touchdown points on the runway relative to centerline and runway threshold. Results indicate that the three operational modes are functionally equivalent when performing climbing and descending turns. Active and unlinked modes were found to be functionally equivalent when flying an ILS approach, but the passive mode, by a small margin, was not found to be functionally equivalent.
Show less - Date Issued
- 2018
- Identifier
- CFE0007242, ucf:52226
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007242
- Title
- Masquerading Techniques in IEEE 802.11 Wireless Local Area Networks.
- Creator
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Nakhila, Omar, Zou, Changchun, Turgut, Damla, Bassiouni, Mostafa, Chatterjee, Mainak, Wang, Chung-Ching, University of Central Florida
- Abstract / Description
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The airborne nature of wireless transmission offers a potential target for attackers to compromise IEEE 802.11 Wireless Local Area Network (WLAN). In this dissertation, we explore the current WLAN security threats and their corresponding defense solutions. In our study, we divide WLAN vulnerabilities into two aspects, client, and administrator. The client-side vulnerability investigation is based on examining the Evil Twin Attack (ETA) while our administrator side research targets Wi-Fi...
Show moreThe airborne nature of wireless transmission offers a potential target for attackers to compromise IEEE 802.11 Wireless Local Area Network (WLAN). In this dissertation, we explore the current WLAN security threats and their corresponding defense solutions. In our study, we divide WLAN vulnerabilities into two aspects, client, and administrator. The client-side vulnerability investigation is based on examining the Evil Twin Attack (ETA) while our administrator side research targets Wi-Fi Protected Access II (WPA2). Three novel techniques have been presented to detect ETA. The detection methods are based on (1) creating a secure connection to a remote server to detect the change of gateway's public IP address by switching from one Access Point (AP) to another. (2) Monitoring multiple Wi-Fi channels in a random order looking for specific data packets sent by the remote server. (3) Merging the previous solutions into one universal ETA detection method using Virtual Wireless Clients (VWCs). On the other hand, we present a new vulnerability that allows an attacker to force the victim's smartphone to consume data through the cellular network by starting the data download on the victim's cell phone without the victim's permission. A new scheme has been developed to speed up the active dictionary attack intensity on WPA2 based on two novel ideas. First, the scheme connects multiple VWCs to the AP at the same time-each VWC has its own spoofed MAC address. Second, each of the VWCs could try many passphrases using single wireless session. Furthermore, we present a new technique to avoid bandwidth limitation imposed by Wi-Fi hotspots. The proposed method creates multiple VWCs to access the WLAN. The combination of the individual bandwidth of each VWC results in an increase of the total bandwidth gained by the attacker. All proposal techniques have been implemented and evaluated in real-life scenarios.
Show less - Date Issued
- 2018
- Identifier
- CFE0007063, ucf:51979
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007063
- Title
- Hole selective tunneling oxide applications with insight into sophisticated characterization techniques.
- Creator
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Ogutman, Nizamettin Kortan, Schoenfeld, Winston, Sundaram, Kalpathy, Batarseh, Issa, Davis, Kristopher, Dogariu, Aristide, University of Central Florida
- Abstract / Description
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Tunneling metal oxide layers combined with industrially applicable novel cleaning methods can boost the current efficiency limit, which corresponds to approximately %22 in production, of crystalline silicon (c-Si) solar cells. Within the scope of this dissertation, extremely thin tunneling layers (1-3nm) of aluminum oxide is studied in conjunction with the development of wet cleaning procedures that are feasible in production lines currently exist today. These tunneling stacks are deployed to...
Show moreTunneling metal oxide layers combined with industrially applicable novel cleaning methods can boost the current efficiency limit, which corresponds to approximately %22 in production, of crystalline silicon (c-Si) solar cells. Within the scope of this dissertation, extremely thin tunneling layers (1-3nm) of aluminum oxide is studied in conjunction with the development of wet cleaning procedures that are feasible in production lines currently exist today. These tunneling stacks are deployed to serve as exceptional surface passivation layers due to the inherent built-in charge provided by aluminum oxide. This capability is further strengthened by the introduction of extremely well controlled wet chemical oxide which not only saturates the dangling bonds at the interface but also enables conformal growth of the aforementioned tunneling oxide layers. Therefore, the interplay between aluminum oxide thickness, which effects the passivation quality tremendously, and carrier extraction capability (contact resistance) is also taken into account by the choice of ultimate boron doping profile and the optimization of the cleaning procedure. The resulting hole collecting surface passivation stack applied on doped surfaces provided record values of recombination current densities, with highly applicable contact resistivity values, enabling one-dimensional carrier transport. This dissertation is also concerned with spatially resolved characterization methods of such industrial c-Si solar cells given the importance of defects that can exist in these large area devices. Analytical image processing algorithms pertaining to biased-photoluminescence (PL) measurements are conducted to portray 2D maps of physical significant devices parameters such as dark saturation current density and efficiency. Finally, Fourier analysis is added into the analysis of raw PL images to pick up only the defected regions of the cells.
Show less - Date Issued
- 2018
- Identifier
- CFE0007069, ucf:51980
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007069
- Title
- Treatment of Leachate Organic Matter through Sunlight Driven Processes.
- Creator
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Lozinski, Duncan, Reinhart, Debra, Lee, Woo Hyoung, Bolyard, Stephanie, University of Central Florida
- Abstract / Description
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The ability to manage leachate during post-closure care (PCC) of a landfill may be increasingly difficult as leachate organic matter (LOM) becomes recalcitrant when a landfill ages, requiring advanced and costly treatment technologies. This research investigated the ability to treat LOM through sunlight driven processes, with a focus on photolysis, to provide insight to landfill owners and operators on the potential of wetlands treatment as a means for reducing long-term risks and costs...
Show moreThe ability to manage leachate during post-closure care (PCC) of a landfill may be increasingly difficult as leachate organic matter (LOM) becomes recalcitrant when a landfill ages, requiring advanced and costly treatment technologies. This research investigated the ability to treat LOM through sunlight driven processes, with a focus on photolysis, to provide insight to landfill owners and operators on the potential of wetlands treatment as a means for reducing long-term risks and costs associated with leachate treatment during PCC. The study was completed in eight batch tests, where leachate was exposed to natural sunlight in central Florida for a period of 90 days. It was hypothesized that through photolytic reactions, in particular photolysis, high molecular weight recalcitrant LOM would be degraded to labile, low molecular weight material. To identify the treatment mechanisms, transformation processes were measured using ultraviolet-visible (UV-Vis) spectroscopy, fluorescence excitation-emission matrix spectroscopy (EEMs), size-exclusion chromatography (SEC), and chemical oxygen demand (COD) from the beginning to the end of the test period. Additionally, the ability for nitrogen species to become bioavailable when exposed to sunlight was evaluated for two of the leachate samples using solid-phase extraction (SPE) to fractionate recalcitrant dissolved organic nitrogen (rDON) and bioavailable dissolved organic nitrogen (bDON). Results suggest that treatment of LOM through sunlight driven processes is possible. Treatment is dependent upon the dilution of leachate and characteristics of the LOM. Dilution must be high enough to allow sunlight to penetrate the depth of the liquid. UV-Vis, EEMs, and SEC show that high molecular weight recalcitrant material is undergoing transformation into lower molecular weight material as a result of photolytic and likely biological reactions promoted by sunlight. The ability for nitrogen to become bioavailable when exposed to sunlight was shown to be dependent upon nitrogen concentrations in the sample.
Show less - Date Issued
- 2018
- Identifier
- CFE0007044, ucf:51987
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007044
- Title
- Split Aptameric Turn-On Fluorescence Sensor for Detection of Sequence Specific Nucleic Acid.
- Creator
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Kikuchi, Nanami, Kolpashchikov, Dmitry, Zhai, Lei, Chumbimuni Torres, Karin, Chen, Gang, Teter, Kenneth, University of Central Florida
- Abstract / Description
-
Nucleic acid amplification tests (NAATs) enable sensitive detection of low density infections that microscopy and rapid diagnostic test are not capable of detecting. They enable quantitative and qualitative nucleic acid detection, genotype analysis, and single nucleotide polymorphism (SNP) detection. Current state of the art molecular probes used with NAATs includes molecular beacon (MB), Taqman and its variations. This work presents novel molecular probe designed from Spinach and Dapoxyl...
Show moreNucleic acid amplification tests (NAATs) enable sensitive detection of low density infections that microscopy and rapid diagnostic test are not capable of detecting. They enable quantitative and qualitative nucleic acid detection, genotype analysis, and single nucleotide polymorphism (SNP) detection. Current state of the art molecular probes used with NAATs includes molecular beacon (MB), Taqman and its variations. This work presents novel molecular probe designed from Spinach and Dapoxyl aptamers. The aptamers are split into two parts (split aptamer), allowing greater sensitivity and selectivity towards fully complementary nucleic acid analyte. The major advantage of split aptamer probe over state-of-the-art fluorescent probes is its high selectivity: in the presence of a single base mismatched analyte, it produces only background fluorescence, even at room temperature. SSA is a promising tool for label-free analysis of nucleic acids at ambient temperatures.Split spinach aptamer (SSA) probes and split dapoxyl aptamer (SDA) for fluorescent analysis of nucleic acids were designed and tested. In both split aptamer design, two RNA or RNA/DNA or DNA strands hybridized to a specific nucleic acid analyte and formed a binding site for fluorescent dye, which was accompanied by up to 270-fold and 69-fold increase in fluorescence. SSAr consisted entirely of ribonucleotides which potentially be expressed in live cells and used for imaging of specific mRNAs. For in vitro RNA/DNA analysis, SDA consisting of entirely DNA are preferable due to greater chemical stability, lower synthetic cost and reduced ability to form intramolecular structures. Additionally, we designed two DNA strands that function as an adapter for SSA and demonstrated how a single universal spinach aptamer (USSA) probe can be used to detect multiple (potentially any) nucleic acid sequences. USSA can be used for cost-efficient and highly selective analysis of even folded DNA and RNA analytes, as well as for the readout of outputs of DNA logic circuits.
Show less - Date Issued
- 2018
- Identifier
- CFE0007031, ucf:51976
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007031
- Title
- Examining Work-To-Rest Ratios To Optimize Upper Body Sprint Interval Training.
- Creator
-
Lamonica, Michael, Fukuda, David, Hoffman, Jay, Stout, Jeffrey, Fragala, Maren, University of Central Florida
- Abstract / Description
-
The primary purpose of this study was to compare the metabolic influence of varying work-to-rest ratios during upper body sprint interval training (SIT). Forty-two recreationally trained men were randomized into one of three training groups [10s work bouts with two minutes of rest (10:2, n = 11) or four minutes of rest (10:4, n = 11), or 30s work bouts with four minutes of rest (30:4, n = 10)] or a control group (CON, n = 10). Participants underwent six training sessions over two weeks with...
Show moreThe primary purpose of this study was to compare the metabolic influence of varying work-to-rest ratios during upper body sprint interval training (SIT). Forty-two recreationally trained men were randomized into one of three training groups [10s work bouts with two minutes of rest (10:2, n = 11) or four minutes of rest (10:4, n = 11), or 30s work bouts with four minutes of rest (30:4, n = 10)] or a control group (CON, n = 10). Participants underwent six training sessions over two weeks with four to six 'all-out' sprints. During pre- and post-intervention visits, participants underwent a graded exercise test to determine maximal oxygen consumption (V?O2peak) and peak power output (PPO), four constant-work rate trials to determine critical power (CP), anaerobic working capacity (W'), and electromyographic fatigue threshold (EMGFT), and an upper body Wingate test to determine peak power (PP), mean power (MP), and total work (TW). Oxygen consumption and blood lactate during the Wingate test generated estimates of oxidative, glycolytic, and ATP-PCr energy system provisions. An analysis of covariance was performed on all testing measurements collected at post with the associated pre-values used as covariates. V?O2peak was greater in 30:4 (p = .007) and 10:2 (p = .036) compared to CON and PPO was greater in 30:4 than CON (p = .007). No differences were observed between groups in CP (p = .530), W' (p = .900), EMGFT (p = .692), PP (p = .692), MP (p = .290), or TW (p = .291). Relative energy contribution (p = .026) and energy expenditure (p = .019) of the ATP-PCr energy system was greater in 10:4 compared to CON. SIT protocols with larger work-to-rest ratios induce enhanced aerobic adaptions, whereas smaller work-to-rest ratios may enhance ATP-PCr utilization in the upper body over a short-term two-week intervention.
Show less - Date Issued
- 2018
- Identifier
- CFE0007036, ucf:51978
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007036
- Title
- State Gun Control Laws.
- Creator
-
Lafleur, Jacob, Huff-Corzine, Lin, Corzine, Harold, Reckdenwald, Amy, University of Central Florida
- Abstract / Description
-
The gun control debate has been placed at the forefront of American politics, as some of the most deadly mass shootings have happened in the last year. Much of the research on the effectiveness of gun control laws have shown inconsistent results. The purpose of the study is to compare states with stricter gun laws to states with more lax laws. This in turn will allow policy makers to identify effective strategies to implement in states that are lacking effective laws. The study examined state...
Show moreThe gun control debate has been placed at the forefront of American politics, as some of the most deadly mass shootings have happened in the last year. Much of the research on the effectiveness of gun control laws have shown inconsistent results. The purpose of the study is to compare states with stricter gun laws to states with more lax laws. This in turn will allow policy makers to identify effective strategies to implement in states that are lacking effective laws. The study examined state gun laws for all 50 states using the Gifford's Law Center to Prevent Gun Violence. The laws that were examined in this study were background checks, license requirements, mental health reporting, wait periods, concealed carry requirements, open carry, disarming prohibited people, and disarming domestic abusers. The states were then given a letter grade based on the laws that they have implemented. The results show that many states have failed to implement any sort of laws that would take guns out of the hands or prevent prohibited people from accessing guns. This study helps identify what laws each state has implemented to control guns throughout their state. This is important because states that are lacking laws in any area can identify and implement effective strategies that other states have put in place.
Show less - Date Issued
- 2018
- Identifier
- CFE0007035, ucf:51985
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007035
- Title
- What #NoWomanEver Wants To Hear: The Social Construction of Corrective Facework After Street Harassment.
- Creator
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Knapp, Emily, Sandoval, Jennifer, Hastings, Sally, Hanlon, Christine, University of Central Florida
- Abstract / Description
-
The purpose of the present study was to investigate the social construction of women's corrective facework after experiencing gender based street harassment. A thematic analysis using open coding was used to explore, examine, and identify themes within the data. Three major themes were revealed in the data and they are 1) a resistance against a cycle of facework, 2) public spaces without accountability, and 3) disproportionate responses from men. In addition to the three themes, I will...
Show moreThe purpose of the present study was to investigate the social construction of women's corrective facework after experiencing gender based street harassment. A thematic analysis using open coding was used to explore, examine, and identify themes within the data. Three major themes were revealed in the data and they are 1) a resistance against a cycle of facework, 2) public spaces without accountability, and 3) disproportionate responses from men. In addition to the three themes, I will present an interpretation of Twitter as a public journal used to resist normative realities of gender based street harassment. These results are important to add to the limited research on the effects of gender based street harassment on women's lived experiences.
Show less - Date Issued
- 2018
- Identifier
- CFE0007032, ucf:51982
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007032
- Title
- Coming to a full stop: An investigation of menstrual period stigmas in college students.
- Creator
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O'Toole, Mary, Sellnow, Deanna, Sandoval, Jennifer, Dodd, Melissa, University of Central Florida
- Abstract / Description
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The focus of this study was to understand perceptions college students have regarding menstruation and if viewing a normalized media message may influence these perceptions. A treatment group of participants was randomly assigned to view an episode of the hit family sitcom Blackish that focused on menstruation and then answer survey questions. A control group of participants only answered the survey questions. A mixed methods analysis revealed three primary conclusions. First, these results...
Show moreThe focus of this study was to understand perceptions college students have regarding menstruation and if viewing a normalized media message may influence these perceptions. A treatment group of participants was randomly assigned to view an episode of the hit family sitcom Blackish that focused on menstruation and then answer survey questions. A control group of participants only answered the survey questions. A mixed methods analysis revealed three primary conclusions. First, these results contradict existing research in that the college students surveyed generally do not hold negative perceptions that may stigmatize menstruation. Second, the treatment that viewed the normalized media message intervention did not report significantly more positive perceptions about menstruation as a natural bodily function than their counterparts in the control group. Third, many participants acknowledged menstruation is a stigmatized topic and media messages not only currently contribute to these attitudes but could be used as a catalyst for guiding society toward normalizing it. These results extend existing research on how people perceive menstruation and on mass media effect research as a means to address stigmatized topics.
Show less - Date Issued
- 2018
- Identifier
- CFE0007066, ucf:51970
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007066
- Title
- The Evolution of Shared Responsibility and Instructional Risk Communication in Brazil's Campaign against the Zika Virus.
- Creator
-
Mauricio Soares, Rodrigo Augusto, Sellnow, Timothy, Sellnow, Deanna, Littlefield, Robert, University of Central Florida
- Abstract / Description
-
This study provides an evaluation of instructional risk communication practices in Brazil's response to the Zika virus during the 2016/2017 campaign. The communication was instructionally focused, explaining the way the disease is transmitted, what to do if the person is infected, and characteristics of the mosquito. The authorities also tried to convince the publics that, because the mosquito breeds in everyone's houses and apartments, everyone could be part of the solution. The social,...
Show moreThis study provides an evaluation of instructional risk communication practices in Brazil's response to the Zika virus during the 2016/2017 campaign. The communication was instructionally focused, explaining the way the disease is transmitted, what to do if the person is infected, and characteristics of the mosquito. The authorities also tried to convince the publics that, because the mosquito breeds in everyone's houses and apartments, everyone could be part of the solution. The social, economic and cultural characteristics of the country, the population's low levels of health literacy, and a long-lasting government credibility problem in the country make Brazil's fight against these types of diseases considerably difficult. The IDEA model (T. Sellnow (&) D. Sellnow, 2013) was used as the theoretical grounding for the analysis. This study presents the concepts of collective efficacy and shared responsibility and recommendations for risk and crisis communication practitioners as well as government agencies with regard to engaging the population in managing this type of disease outbreak. Knowledge about how to generate and share strategic communication of this nature is increasingly important as the spread of novel diseases is increasing in frequency and intensity (Kilpatrick (&) Randolph, 2012).
Show less - Date Issued
- 2018
- Identifier
- CFE0007050, ucf:51974
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007050
- Title
- Style Speaks: Clothing Judgments, Gender Stereotypes, and Expectancy Violations of Professional Women.
- Creator
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Lower, Jamie, Weger, Harry, Sandoval, Jennifer, Miller, Ann, University of Central Florida
- Abstract / Description
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Clothing is a powerful nonverbal communicative tool and form of self-expression that provides others with clues about our personality, mood, education, culture, financial status, and social ranking, amongst numerous other impression cues. Research shows that physical appearance plays a prominent role in the formation of initial judgments and is significant in shaping a person's overall impression on others (Richmond, McCroskey, (&) Payne, 1991). The present study sought to quantitatively...
Show moreClothing is a powerful nonverbal communicative tool and form of self-expression that provides others with clues about our personality, mood, education, culture, financial status, and social ranking, amongst numerous other impression cues. Research shows that physical appearance plays a prominent role in the formation of initial judgments and is significant in shaping a person's overall impression on others (Richmond, McCroskey, (&) Payne, 1991). The present study sought to quantitatively explore the effect that different styles of dress have on initial judgments formed about women in workplace settings. Using expectancy violation theory, the study investigates workplace gender bias and whether or not certain styles of women's dress garner different initial reactions. Results showed that models in feminine attire are perceived to be lower in ratings of dominance and expertise, and models in more masculine attire are perceived to be lower in ratings of kindness and friendliness.
Show less - Date Issued
- 2018
- Identifier
- CFE0007043, ucf:51971
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007043
- Title
- Modeling the innovation ecosystem and development of a dynamic innovation index.
- Creator
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Schoen, Henriette, Karwowski, Waldemar, Hoekstra, Robert, Shumaker, Randall, Akbas, Mustafa, University of Central Florida
- Abstract / Description
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The topic of innovation currently generates a tremendous amount of interest around the world. Innovation is considered an essential part of the solution to creating more jobs and improving the socio-economic conditions of many countries around the globe. Innovation comes about through the existence of many interrelated solutions to socio-economic problems in an extensively interconnected network, which create value for each other. Such a complex creativity and innovation value-creating...
Show moreThe topic of innovation currently generates a tremendous amount of interest around the world. Innovation is considered an essential part of the solution to creating more jobs and improving the socio-economic conditions of many countries around the globe. Innovation comes about through the existence of many interrelated solutions to socio-economic problems in an extensively interconnected network, which create value for each other. Such a complex creativity and innovation value-creating network is here called an Innovation Ecosystem (IE). The main objective of this dissertation research is to improve the current understanding of the IE by developing a simulation model that uses a broad set of relevant static and dynamic variables and incorporates the principles of system dynamics (SD). The proposed model, which is named the IECO-model is based on the relationships between 91 variables and the combined influences of the 43 parameters. Available data for 32 countries, representing a full span of GDP worldwide, was used to study the level of innovation in each of these countries. The result of the developed IECO-model is a novel ranking of the level of innovation through a dynamic innovation index, called the DII. The DII is a new tool to evaluate the innovation and entrepreneurship level of a given country in the context of the global economy. The most significant differentiator from other existing indices of innovation is that the DII is focusing more on the entrepreneurship qualities in 19 of the 43 parameters by looking at cultural values and belief systems, the social context, existing entrepreneurial culture, innovation attitudes, and mentality of each of the considered countries. According to DII-based ranking, the ten most innovative countries in the world are 1. Switzerland, 2. USA, 3. Finland, 4. Netherlands, 5. Iceland, 6. Sweden, 7. Germany, 8. Denmark, 9. The United Kingdom, and 10. Austria.
Show less - Date Issued
- 2018
- Identifier
- CFE0007586, ucf:52537
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007586
- Title
- Serial Murder Mysteries: Revisiting Definitional Issues, Data Challenges, Archaic Theories, and Myths Using Empirical Evidence.
- Creator
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Vincent, Jolene, Huff-Corzine, Lin, Corzine, Harold, Reckdenwald, Amy, Hickey, Eric, University of Central Florida
- Abstract / Description
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While serial killings have been the focus of much scholarly research, the definition of what it means to be a serial killer has been debated by law enforcement agencies and academics for decades. This overall lack of understanding about serial killers and the murders they commit has contributed to the numerous limitations concerning the general knowledge about this unique form of homicide. Furthermore, serial killers have typically been examined using psychological models, psychiatric...
Show moreWhile serial killings have been the focus of much scholarly research, the definition of what it means to be a serial killer has been debated by law enforcement agencies and academics for decades. This overall lack of understanding about serial killers and the murders they commit has contributed to the numerous limitations concerning the general knowledge about this unique form of homicide. Furthermore, serial killers have typically been examined using psychological models, psychiatric approaches, or the external drives/motives of the offenders, while the development of a sociological perspective has received less attention. This current research uses arguably the most complete dataset on serial killings, the Radford database, to fill several gaps in the current body of knowledge by empirically analyzing 1,258 serial killers operating between 1985 and 2016. Data related to the killings, offenders, and victims, in addition to social structural variables, are examined to evaluate how these factors, among others, may possibly be associated with the number of victims an offender killed. Analyzing past definitions and research, this study expands sociological models examining serial murder, and contributes valuable insight into some of the myths and misunderstandings surrounding the crime, and how they likely lead to linkage blindness and decreased homicide clearance rates. Most importantly, this study provides an updated and improved understanding of serial killings that has the potential to be a tool for law enforcement professionals to increase the identity of potential offenders, can ultimately aid their efforts to address sociological origins of serial killing behaviors and attempt to prevent them in the future.
Show less - Date Issued
- 2018
- Identifier
- CFE0007590, ucf:52533
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007590
- Title
- D-FENS: DNS Filtering (&) Extraction Network System for Malicious Domain Names.
- Creator
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Spaulding, Jeffrey, Mohaisen, Aziz, Leavens, Gary, Bassiouni, Mostafa, Fu, Xinwen, Posey, Clay, University of Central Florida
- Abstract / Description
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While the DNS (Domain Name System) has become a cornerstone for the operation of the Internet, it has also fostered creative cases of maliciousness, including phishing, typosquatting, and botnet communication among others. To address this problem, this dissertation focuses on identifying and mitigating such malicious domain names through prior knowledge and machine learning. In the first part of this dissertation, we explore a method of registering domain names with deliberate typographical...
Show moreWhile the DNS (Domain Name System) has become a cornerstone for the operation of the Internet, it has also fostered creative cases of maliciousness, including phishing, typosquatting, and botnet communication among others. To address this problem, this dissertation focuses on identifying and mitigating such malicious domain names through prior knowledge and machine learning. In the first part of this dissertation, we explore a method of registering domain names with deliberate typographical mistakes (i.e., typosquatting) to masquerade as popular and well-established domain names. To understand the effectiveness of typosquatting, we conducted a user study which helped shed light on which techniques were more (")successful(") than others in deceiving users. While certain techniques fared better than others, they failed to take the context of the user into account. Therefore, in the second part of this dissertation we look at the possibility of an advanced attack which takes context into account when generating domain names. The main idea is determining the possibility for an adversary to improve their (")success(") rate of deceiving users with specifically-targeted malicious domain names. While these malicious domains typically target users, other types of domain names are generated by botnets for command (&) control (C2) communication. Therefore, in the third part of this dissertation we investigate domain generation algorithms (DGA) used by botnets and propose a method to identify DGA-based domain names. By analyzing DNS traffic for certain patterns of NXDomain (non-existent domain) query responses, we can accurately predict DGA-based domain names before they are registered. Given all of these approaches to malicious domain names, we ultimately propose a system called D-FENS (DNS Filtering (&) Extraction Network System). D-FENS uses machine learning and prior knowledge to accurately predict unreported malicious domain names in real-time, thereby preventing Internet devices from unknowingly connecting to a potentially malicious domain name.
Show less - Date Issued
- 2018
- Identifier
- CFE0007587, ucf:52540
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007587
- Title
- Nanofiltration of Perfluorinated Compounds as a Function of Water Matrix Properties.
- Creator
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Toure, Hadi, Sadmani, A H M Anwar, Duranceau, Steven, Lee, Woo Hyoung, University of Central Florida
- Abstract / Description
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Perfluorinated compounds (PFCs) have been manufactured and used in various industries including food packaging, paintings, and coating industries. Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) are the most commonly investigated PFCs that have bioaccumulative properties and a strong persistence in environment. Despite the growing interest in using membrane technology to remove PFOA and PFOS from water, little information is available on the impact of natural water...
Show morePerfluorinated compounds (PFCs) have been manufactured and used in various industries including food packaging, paintings, and coating industries. Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) are the most commonly investigated PFCs that have bioaccumulative properties and a strong persistence in environment. Despite the growing interest in using membrane technology to remove PFOA and PFOS from water, little information is available on the impact of natural water matrices on the removal of PFOA and PFOS when using nanofiltration (NF). The presence of natural organic matter (NOM) and cations (Ca2+ and Mg2+) in water matrices and their interactions with the PFCs may significantly impact their removal efficiency. The current study compared the rejection of PFOA and PFOS from laboratory-prepared water (deionized water), surface water and groundwater using a commercial NF membrane (NE 70). Three different experiments were conducted for 20 hours using a bench- scale flat sheet unit. Feed and permeate samples were collected and analyzed to determine the PFOA and PFOS concentrations using liquid chromatography-tandem mass spectrometry (LC/MS-MS). The compound rejections varied from 71 to 80 % for PFOA and 42 to 80 % for PFOS. The results showed increased rejection of PFOA/S in the surface water and groundwaters when compared to the laboratory-prepared water. This is likely due to the presence of NOM and cations in the natural water matrices. The permeate flux declined (12.3-56.2 %) as more cations and NOM were present in the feedwater, suggesting that the increased rejection of PFOS in natural waters may be due to membrane pore blockage.
Show less - Date Issued
- 2018
- Identifier
- CFE0007589, ucf:52539
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007589
- Title
- Large Scale Cryogenic Storage With Active Refrigeration.
- Creator
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Swanger, Adam, Chow, Louis, Kapat, Jayanta, Notardonato, William, University of Central Florida
- Abstract / Description
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Storage and transfer of cryogenic liquefied gases on volume scales from under 10 liters for lab use, up to hundreds of millions of liters for industrial applications is of paramount importance across a vast range of industries. Traditionally, these commodities have been stored at or near the normal boiling point due to relative ease of operation and safety-related considerations; however, this also means that some percentage will always be lost due to environmental heat leaking into the...
Show moreStorage and transfer of cryogenic liquefied gases on volume scales from under 10 liters for lab use, up to hundreds of millions of liters for industrial applications is of paramount importance across a vast range of industries. Traditionally, these commodities have been stored at or near the normal boiling point due to relative ease of operation and safety-related considerations; however, this also means that some percentage will always be lost due to environmental heat leaking into the vessel and causing boiloff. These losses become more concerning as scales increase, and are of particular importance for high-cost commodities such helium and hydrogen. Additionally, the normal boiling point has typically marked the highest liquid density achievable, which became a strong driver of end-use system designs such as space launch vehicles. Recent development and testing of an Integrated Refrigeration and Storage (IRAS) system for liquid hydrogen has proven that next generation cryogenic storage operations such as zero boiloff and densification are feasible on a large scale. This IRAS system married an 850 Watt at 20 Kelvin reverse-Brayton cycle commercial cryogenic refrigerator with a 125,000 liter LH2 storage tank via an internal tubular heat exchanger; thereby allowing heat to be removed directly from the hydrogen, and by extension, providing a means to control the bulk thermodynamic state. Tests of zero boiloff, in-situ liquefaction, and densification down to the triple point were performed, and data including fluid temperature profiles and tank pressure were gathered. Details regarding the design, setup, and testing of the IRAS system are discussed herein, and the data are used to anchor various physics models created to predict the behavior of the system during both transient and steady state operations. Hopefully these efforts will provide a useful basis for the design and implementation of future large scale IRAS systems across numerous industries.
Show less - Date Issued
- 2018
- Identifier
- CFE0007588, ucf:52530
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007588
