Matching Items (260)
Description
The goal of the studies described in this thesis was to determine the changes in vascular density in the paraventricular nucleus (PVN) of the hypothalamus following prenatal exposure to the synthetic glucocorticoid hormone, dexamethasone (DEX). DEX is a synthetic glucocorticoid used clinically in women at risk for preterm delivery or in preterm infants to promote proper pulmonary development in high-risk neonates. Prenatal exposure to glucocorticoids such as DEX may change the development of important brain regulatory centers such as the PVN, resulting in increased risk for diseases in adulthood.
Previous studies have demonstrated that the hypothalamus regulates neuroendocrine and autonomic function and behavior. Within the hypothalamus, the paraventricular nucleus (PVN) is an integratory node that contains neurons associated with the control of neuroendocrine and autonomic responses. The PVN also has one of the highest density of blood vessels within the brain. Alterations of normal PVN angiogenesis by dexamethasone could potentially result in long-term modifications of brain and endocrine functions.
Timed-pregnant Sprague Dawley female rats received DEX on gestational days 18-21 and the resulting progeny were sacrificed at Postnatal Day (PND) 0, 4, 14, and 21. A tomato lectin, Lycopersicon Esculentum labeled with DyLight594 was used to stain blood vessels in the PVN and scanning confocal microscopy was used to analyze the experimental brains for PVN blood vessel density
Analysis of data using a 3-way analysis of variance (ANOVA) with age, sex and treatment as main factors, showed a significant age effect in vascular density. Analysis of female data by 2-way ANOVA demonstrated a significant effect of age, but no treatment or interaction effects. Post-hoc analysis shows significant differences at PND 2, 4, 14, and 21 compared to PND0. A Student‘s t-test of a planned comparison on PND2 showed a significant reduction by DEX treatment (p < 0.05). Analysis of data from females, using 2-way ANOVA demonstrated a significant effect of age, but no treatment or interaction effects. Post-hoc analysis shows significant differences at PND 2, 4, 14, and 21 compared to PND0. A planned comparison at PND 2 using Student’s t-test indicated a significant reduction by dex treatment.
The results of these studies demonstrate that there is significant postnatal angiogenic programming and that the vascular density of the PVN is altered by prenatal dexamethasone administration at PND2. The time-course shows developmental fluctuations in vessel density that may prove to be physiologically significant for normal brain function and developmental programming of brain and behavior.
Previous studies have demonstrated that the hypothalamus regulates neuroendocrine and autonomic function and behavior. Within the hypothalamus, the paraventricular nucleus (PVN) is an integratory node that contains neurons associated with the control of neuroendocrine and autonomic responses. The PVN also has one of the highest density of blood vessels within the brain. Alterations of normal PVN angiogenesis by dexamethasone could potentially result in long-term modifications of brain and endocrine functions.
Timed-pregnant Sprague Dawley female rats received DEX on gestational days 18-21 and the resulting progeny were sacrificed at Postnatal Day (PND) 0, 4, 14, and 21. A tomato lectin, Lycopersicon Esculentum labeled with DyLight594 was used to stain blood vessels in the PVN and scanning confocal microscopy was used to analyze the experimental brains for PVN blood vessel density
Analysis of data using a 3-way analysis of variance (ANOVA) with age, sex and treatment as main factors, showed a significant age effect in vascular density. Analysis of female data by 2-way ANOVA demonstrated a significant effect of age, but no treatment or interaction effects. Post-hoc analysis shows significant differences at PND 2, 4, 14, and 21 compared to PND0. A Student‘s t-test of a planned comparison on PND2 showed a significant reduction by DEX treatment (p < 0.05). Analysis of data from females, using 2-way ANOVA demonstrated a significant effect of age, but no treatment or interaction effects. Post-hoc analysis shows significant differences at PND 2, 4, 14, and 21 compared to PND0. A planned comparison at PND 2 using Student’s t-test indicated a significant reduction by dex treatment.
The results of these studies demonstrate that there is significant postnatal angiogenic programming and that the vascular density of the PVN is altered by prenatal dexamethasone administration at PND2. The time-course shows developmental fluctuations in vessel density that may prove to be physiologically significant for normal brain function and developmental programming of brain and behavior.
ContributorsWidener, Andrew John-Claude (Author) / Handa, Robert (Thesis director) / Orchinik, Miles (Committee member) / Mustard, Julie (Committee member) / Barrett, The Honors College (Contributor) / Department of Chemistry and Biochemistry (Contributor)
Created2014-05
Description
A coincidence reporter construct, consisting of the p21-promoter and two luciferase genes (Firefly and Renilla), was constructed for the screening of drugs that might inhibit Olig2's tumorigenic role in glioblastoma. The reporter construct was tested using an Olig2 inhibitor, HSP990, as well as short hairpin RNA targeting Olig2. Further confirmatory analysis is needed before the reporter cell line is ready for high-throughput screening at the NIH and lead compound selection.
ContributorsCusimano, Joseph Michael (Author) / LaBaer, Joshua (Thesis director) / Mangone, Marco (Committee member) / Mehta, Shwetal (Committee member) / Barrett, The Honors College (Contributor) / Department of Chemistry and Biochemistry (Contributor)
Created2014-05
Description
Phytochromes are a family of photoreceptors that control light responses of plants, fungi and bacteria. A sequence of structural changes, which is not yet fully understood, leads to activation of an output domain. Time-resolved serial femtosecond crystallography (SFX) can potentially shine light on these conformational changes. Here we report the room temperature crystal structure of the chromophore-binding domains of the Deinococcus radiodurans phytochrome at 2.1 Å resolution. The structure was obtained by serial femtosecond X-ray crystallography from microcrystals at an X-ray free electron laser. We find overall good agreement compared to a crystal structure at 1.35 Å resolution derived from conventional crystallography at cryogenic temperatures, which we also report here. The thioether linkage between chromophore and protein is subject to positional ambiguity at the synchrotron, but is fully resolved with SFX. The study paves the way for time-resolved structural investigations of the phytochrome photocycle with time-resolved SFX.
ContributorsEdlund, Petra (Author) / Takala, Heikki (Author) / Claesson, Elin (Author) / Henry, Leocadie (Author) / Dods, Robert (Author) / Lehtivuori, Heli (Author) / Panman, Matthijs (Author) / Pande, Kanupriya (Author) / White, Thomas (Author) / Nakane, Takanori (Author) / Berntsson, Oskar (Author) / Gustavsson, Emil (Author) / Bath, Petra (Author) / Modi, Vaibhav (Author) / Roy Chowdhury, Shatabdi (Author) / Zook, James (Author) / Berntsen, Peter (Author) / Pandey, Suraj (Author) / Poudyal, Ishwor (Author) / Tenboer, Jason (Author) / Kupitz, Christopher (Author) / Barty, Anton (Author) / Fromme, Petra (Author) / Koralek, Jake D. (Author) / Tanaka, Tomoyuki (Author) / Spence, John (Author) / Liang, Mengning (Author) / Hunter, Mark S. (Author) / Boutet, Sebastien (Author) / Nango, Eriko (Author) / Moffat, Keith (Author) / Groenhof, Gerrit (Author) / Ihalainen, Janne (Author) / Stojkovic, Emina A. (Author) / Schmidt, Marius (Author) / Westenhoff, Sebastian (Author) / College of Liberal Arts and Sciences (Contributor) / School of Molecular Sciences (Contributor) / Biodesign Institute (Contributor) / Applied Structural Discovery (Contributor) / Department of Physics (Contributor)
Created2016-10-19
Description
Serial femtosecond crystallography (SFX) using X-ray free-electron laser sources is an emerging method with considerable potential for time-resolved pump-probe experiments. Here we present a lipidic cubic phase SFX structure of the light-driven proton pump bacteriorhodopsin (bR) to 2.3 Å resolution and a method to investigate protein dynamics with modest sample requirement. Time-resolved SFX (TR-SFX) with a pump-probe delay of 1 ms yields difference Fourier maps compatible with the dark to M state transition of bR. Importantly, the method is very sample efficient and reduces sample consumption to about 1 mg per collected time point. Accumulation of M intermediate within the crystal lattice is confirmed by time-resolved visible absorption spectroscopy. This study provides an important step towards characterizing the complete photocycle dynamics of retinal proteins and demonstrates the feasibility of a sample efficient viscous medium jet for TR-SFX.
ContributorsNogly, Przemyslaw (Author) / Panneels, Valerie (Author) / Nelson, Garrett (Author) / Gati, Cornelius (Author) / Kimura, Tetsunari (Author) / Milne, Christopher (Author) / Milathianaki, Despina (Author) / Kubo, Minoru (Author) / Wu, Wenting (Author) / Conrad, Chelsie (Author) / Coe, Jesse (Author) / Bean, Richard (Author) / Zhao, Yun (Author) / Bath, Petra (Author) / Dods, Robert (Author) / Harimoorthy, Rajiv (Author) / Beyerlein, Kenneth R. (Author) / Rheinberger, Jan (Author) / James, Daniel (Author) / Deponte, Daniel (Author) / Li, Chufeng (Author) / Sala, Leonardo (Author) / Williams, Garth J. (Author) / Hunter, Mark S. (Author) / Koglin, Jason E. (Author) / Berntsen, Peter (Author) / Nango, Eriko (Author) / Iwata, So (Author) / Chapman, Henry N. (Author) / Fromme, Petra (Author) / Frank, Matthias (Author) / Abela, Rafael (Author) / Boutet, Sebastien (Author) / Barty, Anton (Author) / White, Thomas A. (Author) / Weierstall, Uwe (Author) / Spence, John (Author) / Neutze, Richard (Author) / Schertler, Gebhard (Author) / Standfuss, Jorg (Author) / College of Liberal Arts and Sciences (Contributor) / Department of Physics (Contributor) / Department of Chemistry and Biochemistry (Contributor) / Biodesign Institute (Contributor) / Applied Structural Discovery (Contributor) / School of Molecular Sciences (Contributor)
Created2016-08-22
Description
Serial femtosecond crystallography requires reliable and efficient delivery of fresh crystals across the beam of an X-ray free-electron laser over the course of an experiment. We introduce a double-flow focusing nozzle to meet this challenge, with significantly reduced sample consumption, while improving jet stability over previous generations of nozzles. We demonstrate its use to determine the first room-temperature structure of RNA polymerase II at high resolution, revealing new structural details. Moreover, the double flow-focusing nozzles were successfully tested with three other protein samples and the first room temperature structure of an extradiol ring-cleaving dioxygenase was solved by utilizing the improved operation and characteristics of these devices.
ContributorsOberthuer, Dominik (Author) / Knoska, Juraj (Author) / Wiedorn, Max O. (Author) / Beyerlein, Kenneth R. (Author) / Bushnell, David A. (Author) / Kovaleva, Elena G. (Author) / Heymann, Michael (Author) / Gumprecht, Lars (Author) / Kirian, Richard (Author) / Barty, Anton (Author) / Mariani, Valerio (Author) / Tolstikova, Aleksandra (Author) / Adriano, Luigi (Author) / Awel, Salah (Author) / Barthelmess, Miriam (Author) / Dorner, Katerina (Author) / Xavier, P. Lourdu (Author) / Yefanov, Oleksandr (Author) / James, Daniel (Author) / Nelson, Garrett (Author) / Wang, Dingjie (Author) / Calvey, George (Author) / Chen, Yujie (Author) / Schmidt, Andrea (Author) / Szczepek, Michael (Author) / Frielingsdorf, Stefan (Author) / Lenz, Oliver (Author) / Snell, Edward (Author) / Robinson, Philip J. (Author) / Sarler, Bozidar (Author) / Belsak, Grega (Author) / Macek, Marjan (Author) / Wilde, Fabian (Author) / Aquila, Andrew (Author) / Boutet, Sebastien (Author) / Liang, Mengning (Author) / Hunter, Mark S. (Author) / Scheerer, Patrick (Author) / Lipscomb, John D. (Author) / Weierstall, Uwe (Author) / Kornberg, Roger D. (Author) / Spence, John (Author) / Pollack, Lois (Author) / Chapman, Henry N. (Author) / Bajt, Sasa (Author) / College of Liberal Arts and Sciences (Contributor) / Department of Physics (Contributor)
Created2017-03-16
Description
The effects of meditation on attention control have been widely studied in recent years. However, the methodological flaws of many of these studies raise serious concerns on the validity of meditation training as a cognitive enhancer. This study investigated the near and far transfer effects of mindfulness meditation training on attention control when a stringent experimental design was implemented. Participants in the experimental group practiced meditation for three twenty-minute sessions, and participants in the active control group listened to an audio book about meditation for similar times. No significant effect of meditation on change in performance on cognitive tasks was found. This study suggests that short-term mindfulness meditation training does not result in increased attention control.
ContributorsPatel, Sachi Rajul (Author) / Brewer, Gene (Thesis director) / Presson, Clark (Committee member) / Davis, Mary (Committee member) / Barrett, The Honors College (Contributor) / Department of Chemistry and Biochemistry (Contributor) / Department of Psychology (Contributor) / School of Historical, Philosophical and Religious Studies (Contributor)
Created2013-05
Description
ASU4Food's objective is to increase the visibility of the statewide hunger crisis among Arizona State University's campuses, and to raise monetary and food donations to alleviate this issue. By collaborating with a multitude of organizations both on and off-campus, we aim to become a well-known, powerful, and stable student organization. This thesis will cover the endeavors of Elana Niren, Theresa Reckamp, and Sidath Wijetunga regarding the maintenance, growth, and expansion of ASU4Food. ASu4Food has been striving to gain connections and the reputation that would allow it to become an "umbrella organization" with the ability to coordinate all of the food-raising endeavors at ASU. The effects of our actions can be seen in the club's stability. We are now being sought out by organizations such as the Salvation Army, Sunflower Farmers Market, and Shutterfly. However, there is still more work to be done, and we hope that this thesis will act as a guide for future generation of club members and officers, and that ASU4Food will continue improving in activity and efficiency for many years to come.
ContributorsNiren, Elana (Co-author) / Reckamp, Theresa (Co-author) / Wijetunga, Sidath (Co-author) / Eaton, John (Thesis director) / Mokwa, Michael (Committee member) / Southergill, Keith (Committee member) / Barrett, The Honors College (Contributor) / Department of Chemistry and Biochemistry (Contributor)
Created2013-05
Description
The Walter Cronkite School of Journalism and Mass Communications stands as a "gold standard" of journalism education throughout the country. In my time at the school though, I found that some aspects in the whole of the curriculum were missing. I as well as several other friends became interested in production and the technical side of things. This seemed to be the direction we wanted to go and soon realized this played a crucial part in journalism. Although there is a studio production class and a studio production track through the immersive Cronkite News program, there is not much in between. This inspired me to take a look deeper into production skills and their place within a journalism education. The project is split into three main sections that dive into the ideas of teaching production skills and technical skills to journalism students and whether or not it is valuable. The first part is the background of the project and why this project came to be. The background section explores the inspiration for the project. The project continues with a look at job statistics and where the industry currently sits. This continues into the final section that contains personal stories and interviews with professionals in the field. This is a critical section to back up claims made through research and evaluation. There is a lot of personal experience and non-traditional research done through this project, but the assertions and conclusions made are clear. Through job statistics, personal stories, and interviews with professionals, this project examines how production could be taught in a traditional journalism program. These stories show that a journalism curriculum may not be the best place to teach production in depth, but that it still is an incredibly important part of the journalism world as a whole.
ContributorsHardy, Joseph Michael (Author) / Jacoby, Jim (Thesis director) / McJannet, Rob (Committee member) / College of Public Service and Community Solutions (Contributor) / Walter Cronkite School of Journalism and Mass Communication (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
The Chinese tourism market has become the largest tourism market in the world and continues to show promise in its future development. Global destinations such as Southeast Asia, France and now Australia have begun to see a major boom in Chinese tourists within the past decade due to less restrictive travel policies, a growing economy and higher disposable income rates within urban centers in China. Australia has become the top destination among Chinese citizens that wish to travel due to its coastal and beach attractions, unique wildlife, and general welcoming attitude toward Chinese citizens. As the market continues to grow, the characteristics and demographics change as well. The Chinese government did not allow for international travel until the early 1990s. During this time, package tours offered by government-regulated travel agencies were the prominent method of travel planning with travelers over the age of 35 making up the majority of travelers. However, in the past decade there has been a shift from group travel toward independent travel due to higher income and more independence among young adults. There remains a stigma against Chinese tourists due to behavioral and cultural challenges Chinese tourists face when traveling abroad, but as Chinese travelers begin to travel in smaller groups and have greater exposure to international cultures, these negative stereotypes will start to disappear. This paper focuses on the impact the Chinese tourism market has on Cairns, Australia. Cairns is characterized by its backpacking culture, easy access to environmental attractions and a high number of annual travelers from Asia and China specifically. The paper uses qualitative research and compiles information from news sources, government documents and statistical data regarding Chinese outbound tourism and its impacts on Australian tourism. There is also a case study composed of personal observations of a nature park in North Queensland which uses specific marketing and attraction coordination to appeal to Chinese tourists. This case study analyzes the tactics used by local destinations that cater to group travel over independent travel and points out the benefits of this type of specialized tourism. The research concludes by arguing the trend toward independent travel is beneficial to the Cairns tourism industry rather than harmful as long as the industry recognizes the new trends in Chinese tourism and does not focus on the previous trends of group travel when appealing to Chinese tourists. Instead, the industry should continue to focus on the backpacking culture and work toward catering to the demands of millennial travelers.
ContributorsRochon, Jacob Henri (Author) / Goodman, Rebekka (Thesis director) / McWilliams, Claire (Committee member) / College of Public Service and Community Solutions (Contributor) / School of Politics and Global Studies (Contributor) / School of International Letters and Cultures (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
An important question that needs to be discussed is whether drug detection dogs can be used the same way as machines in assisting drug detection and how these drug detection dogs should be used under the Fourth Amendment. In answering these questions, the history, training, certifications, and case law relating to drug detection dogs should be reviewed. The dogs are powerful tools in the detection of narcotics, but it is critical to remember that they are only animals and far from flawless. They can make mistakes because of lapses in training, due to irregular training and certification standards, or cues, intentional or not, from their handlers. Under current precedent, walking around something, like a car, is not a search and does not require reasonable suspicion. A dog alert during this non-intrusive, superficial contact can give rise to probable cause to search. If the dog alert is not reliable, it can lead to many unnecessary searches that violate people's privacy. In order to protect Fourth Amendment rights from the, drug detection dogs need to be used carefully and with limitations. A dog's ability to smell is impressive and humans' ability to train them is vast, but a dog is just a dog. The limited accuracy of a dog sniff is not an issue when they are used to search for people in landslides or avalanches, because even 10% accuracy is helpful when trying to save someone's life. However, when a drug detection dog is used to establish probable cause for a search, accuracy becomes an issue. United States v. Place was based on faulty scientific evidence on the accuracy of dogs, and it set the standard for future drug detection dog cases. The courts need to revisit this issue in light of more recent information. Except in certain locations where Fourth Amendment rights are limited, drug detection dogs should only be used when reasonable suspicion of criminal conduct exists. This limitation, as well as enhanced training and certification standards, strikes the appropriate balance between living in a civilized society and living in a secure society.
ContributorsGodinez, Katherine Mary (Author) / Stanford, Michael (Thesis director) / Kirchler, Rebecca (Committee member) / Barrett, The Honors College (Contributor) / Department of Chemistry and Biochemistry (Contributor) / Sandra Day O'Connor College of Law (Contributor)
Created2014-05