Matching Items (45)
Description
In oxygenic photosynthesis, conversion of solar energy to chemical energy is catalyzed by the<br/>pigment-protein complexes Photosystem II (PSII) and Photosystem I (PSI) embedded within the<br/>thylakoid membrane of photoautotrophs. The function of these pigment-protein complexes are<br/>conserved between all photoautotrophs, however, the oligomeric structure, as well as the<br/>spectroscopic properties of the PSI complex, differ. In early evolving photoautotrophs, PSI<br/>exists in a trimeric organization, but in later evolving species this was lost and PSI exists solely<br/>as a monomer. While the reasons for a change in oligomerization are not fully understood, one<br/>of the 11 subunits within cyanobacterial PSI, PsaL, is thought to be involved in trimerization<br/>through the coordination of a calcium ion in an adjacent monomer. Recently published<br/>structures have demonstrated that PSI complexes are capable of trimerization without<br/>coordinating the calcium ion within PsaL.<br/>5 Here we explore the role the calcium ion plays in both<br/>the oligomeric and spectroscopic properties in PSI isolated from Synechocystis sp. PCC 6803.
ContributorsVanlandingham, Jackson R (Author) / Mazor, Yuval (Thesis director) / Mills, Jeremy (Committee member) / School of Life Sciences (Contributor) / School of Molecular Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
Description
The boom in publicly-funded sports facility construction since the 1980s resulted in studies that generally found the economic benefits accruing from facility construction do not justify the costs. However, focusing narrowly on economic costs in large cities leaves out an important part of the story. The author is interested in the possible non-economic benefits to a city from having a sports team and stadium, and focuses on determining any relationship between minor league teams and stadiums and community self-image. The methodology for this review is an assessment of the websites – primarily the website's front page – for 42 cities with minor league baseball teams. In addition, a survey of local government officials provides a layer of corroboration for the website review results. Through this assessment, the author brings together elements that contribute to three different fields – facility financing, e-government, and small and mid-sized cities. The website reviews have two elements. First, the author assesses the extent to which the website provides information about the team and stadium on the front page or a website page within two links from the front page. The result is that a relatively low amount of information about teams and stadiums is available on the 42 city websites. Second, the author assesses all the active links on the website front page and categorize the links regarding whether they are primarily directed toward residents, businesses, or tourists. On average 67 percent of the links on the 42 city websites' front pages are directed toward residents. In addition to the website reviews, the author reports on a survey of local government executives and managers regarding the city websites. The key findings from the survey are that residents are the group of most interest to the website creators; the websites' content and appearance generally are intended to reflect the communities' self-image, and; in general, the low amount of information about the teams and stadiums on the website front page accurately represents the importance of the teams and stadiums to communities' self-image. The survey results generally corroborate the website reviews.
ContributorsHorton, Christopher N (Author) / Yoshioka, Carlton (Thesis advisor) / Chapman, Jeffrey (Committee member) / Danzig, Arnold (Committee member) / Arizona State University (Publisher)
Created2012
Description
Research was conducted on the topic of Arizona's Department of Emergency Management. Specifically, the research and creative project was centered on the Search and Rescue Branch of the department. The creative project covered the key aspects and elements of Search and Rescue organization, legal considerations, preparation, training, teams, and safety. These different elements heavily impact the Search and Rescue teams of Arizona. The researched information was compiled into a paper and the overall themes were used as inspiration for a series of paintings. The paintings highlight the components that were researched and presented in the written paper.
ContributorsSavala, Renae Alejandrina (Author) / Yoshioka, Carlton (Thesis director) / Kozakiewicz, Scott (Committee member) / Barrett, The Honors College (Contributor) / W. P. Carey School of Business (Contributor) / Department of Supply Chain Management (Contributor)
Created2015-05
Description
Continuing work has been done on a novel class of anti-cancer drugs employing a vinylogous extended amidine system functionalized into benzimidazole ring. Three new derivatives, utilizing a true sugar mimic at the N1-position, have been synthesized. Compounds 6-amino-1-[2-(2-hydroxyethoxy)ethyl-4-imino-2,5-dimethyl-1H-benzimidazole- 7-one (5), 6-amino-1-[2-(2-hydroxysulfonoethoxy)ethyl-4-imino-2,5-dimethyl-1H-benzimidazole-7-one (6), and 6-amino-1-[2-(2-hydroxysulfonoethoxy)ethyl-4-methylimino-2,5-dimethyl-1H-benzimidazole-7-one (7) have been synthesized utilizing similar protocols used in the synthesis of previously screened anti-tumor drugs produced by this laboratory. Compounds (5) and (6) have undergone screening similar to the National Cancer Institute’s (NCIs) Developmental Therapeutic Program (DTP), performed by Dr. Dan LaBarbera at the University of Boston. Both compounds show high cytotoxicity, with complete cell death at 5 µM and bioactive concentrations in the low nanomolar concentrations; more complete data is forthcoming. The proposed mechanism of action is through inhibition of p90RSK 1-2 which is responsible for the phosphorylation of Bcl-2 associated death promoter (BAD), a key metabolite in directing the onset of apoptosis. Future directions of next generation derivatives include modifying the 2-position of the benzimidazole ring into a halogenating or alkylating agent and possibly replacing the methanesulfonate with a phosphate group. This research is being published in the Journal of Medicinal Chemistry.
ContributorsMorrison, Zachary Tyler (Author) / Skibo, Edward (Thesis director) / Lefler, Scott (Committee member) / Barrett, The Honors College (Contributor) / Department of Chemistry and Biochemistry (Contributor)
Created2014-05
Description
Short-term medical volunteer work via a nongovernmental organization is a popular tool for students in the health care field to gain experience, while further providing communities that normally lack health care options the opportunity to receive free care. One such organization, VIDA Volunteer Travel, has been successful in implementing this model in Central America. However, organizations of this form have not been evaluated for effectiveness or improvement. This exploratory study examines the effectiveness of VIDA based on six qualifying characteristics that make up a successful NGO. The researcher conducted in-depth, semi-structured interviews with 21 individuals, including VIDA staff members in Costa Rica and Nicaragua, health professionals working for VIDA, local community leaders, and volunteers participating in VIDA's programs. Summaries and quotes of these interviews were uploaded and analysed using Atlas.ti to identify common words and themes from the interviews. Informants frequently identified the organization as sustainable, both from a fiscal and ecological standpoint. The organization also successfully managed volunteers, although post-trip follow-up was lacking. Adherence to the mission statement and distribution of supplies allowed for improved organization and successful structure of the organization. Education and health promotion was also emphasized, although implementation of this education into the communities was lacking. Collaboration with the community and volunteers allowed for stringent, successful treatment to be given to patients, and ethical guidelines set up by the organization allowed for self-governance and improvement of the NGO. This study suggests future research opportunities for the organization, to evaluate its own impact and opportunities for improvement. Furthermore, suggestions are addressed that allow the organization to improve upon its well-implemented infrastructure, and allow for future organizations to use VIDA as a model for improvement.
ContributorsPearson, Presley Kyle (Author) / Yoshioka, Carlton (Thesis director) / Wang, Lili (Committee member) / Larsen, Dale (Committee member) / Barrett, The Honors College (Contributor) / School of International Letters and Cultures (Contributor)
Created2013-05
Description
Peer-reviewed literature on the effects of sound and music on babies ranging from the prenatal period to the postnatal period, called the perinatal period moving forward, is vast. Substantial research has been directed towards the neural connections they make with sound, musical therapy, audio learning, and much more. The primary focus of this thesis was to review the current literature on how the father's voice affects the fetus during the perinatal period. During the preliminary research of the topic, the process faced an immediate problem as this concept had very little substantial sources. The number of relevant articles or documents with the term “father” in the title can be counted on one hand. In some cases, research that explored the father’s voice did so only as a supporting statistic or comparison to the main goal of exploring the mother’s voice. The mother’s voice has been prioritized as a research topic because of the immediate physical connection between the mother and the child throughout the entire pregnancy. The third semester of pregnancy is often a period of study since what the mother senses, says or does will somehow translate into an experience for the child’s developing brain. On the other hand, the father’s voice has been considered an environmental sound, a position justified by some researchers due to phenomena such as differing levels of fetal attention and observed “preference” of a newborn. The scarcity of research regarding the father’s voice, or the voice of a non-parental male, can be explained in several ways. These include the father’s potential absence due to work, inherited ideologies and biases against active parenting for the father, parental roles, and their unwillingness to utilize infant-directed speech and singing for psychological reasons, during the perinatal period, compared to that of the mother. Researching ways to deepen the relationship between the father and baby during the perinatal period, along with developing new biotechnologies for different kinds of evaluative tests, will help advance the subject matter of how the father’s voice impacts a baby to a larger scale.
ContributorsNguyen, Justin Dinh Huy (Author) / Norton, Kay (Thesis director) / Lefler, Scott (Committee member) / School of Music, Dance and Theatre (Contributor) / School of Molecular Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
Description
DNA nanotechnology uses the reliability of Watson-Crick base pairing to program and generate two-dimensional and three-dimensional nanostructures using single-stranded DNA as the structural material. DNA nanostructures show great promise for the future of bioengineering, as there are a myriad of potential applications that utilize DNA’s chemical interactivity and ability to bind other macromolecules and metals. DNA origami is a method of constructing nanostructures, which consists of a long “scaffold” strand folded into a shape by shorter “staple” oligonucleotides. Due to the negative charge of DNA molecules, divalent cations, most commonly magnesium, are required for origami to form and maintain structural integrity. The experiments in this paper address the discrepancy between salt concentrations required for origami stability and the salt concentrations present in living systems. The stability of three structures, a two-dimensional triangle, a three-dimensional solid cuboid and a three-dimensional wireframe icosahedron were examined in buffer solutions containing various concentrations of salts. In these experiments, DNA origami structures remained intact in low-magnesium conditions that emulate living cells, supporting their potential for widespread biological application in the future.
ContributorsSeverson, Grant William (Author) / Stephanopoulos, Nicholas (Thesis director) / Mills, Jeremy (Committee member) / School of Molecular Sciences (Contributor) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
Mass nuclear catastrophe is a serious concern for society at large when considering the rising threat of terrorism and the risks associated with harnessing nuclear energy. In the case of a mass nuclear/radiological event that requires hundreds of thousands of individuals to be assessed for radiation exposure, a rapid biodosimetry triage tool is crucial [1]. The Cytokinesis Block Micronucleus Assay (CBMN) is a promising cytogenetic biodosimetry assay for triage [2]; however, it requires shipping samples to a central laboratory (1-3 days) followed by a lengthy cell culture process (~3 days) before the first dose estimate can be available. The total ~ 1 week response time is too long for effective medical care intervention. A shipping incubator could cut the response time in half (~3 days) by culturing samples in transit; however, possible shipping delays beyond 2 days without the addition of a necessary reagent (Cyto-B) would ruin the integrity of the samples—for accurate CBMN assay endpoint observation, Cyto-B must be added within a 24-44 hour window after sample culture is initiated. Here, we propose a “Smart” Shipping Incubator (SSI) that can add Cyto-B while samples are in transit through a centrifugal system equipped with microfluidic capillary valve caps. The custom centrifugal system was constructed with CNC machined and 3D printed plastic parts, controlled by a custom printed circuit board (PBC) microcontroller, and housed inside a commercial shipping incubator (iQ5 from MicroQ Technologies). Teflon-coated, pre-pulled glass micropipettes (FivePhoton BioChemicals) were used as microfluidic capillary valve caps. Release of Cyto-B was characterized by a desktop centrifugal system at different tip sizes and relative centrifugal forces (RCFs). A theoretical model of Cyto-B release was also deduced to aid the optimization of the process. The CBMN assay was conducted both in the SSI with centrifugal Cyto-B release and in a standard CO2 incubator with manual addition of Cyto-B as the control. The expected mechanical shock during shipment was measured to be less than 25g. Optimal Cyto-B release was found to be at 35g RCF with a Teflon-coated 40 µm tip. Similar CBMN dose curves of micronuclei per binucleated cells (MN/BN) vs. exposed radiation (Gy) were produced for samples assessed conventionally and with the SSI. The similarities between the two methods suggest that centrifugation does not significantly affect the CBMN assay.
ContributorsAkkad, Adam Rifat (Author) / Stephanopoulos, Nicholas (Thesis director) / Mills, Jeremy (Committee member) / Gu, Jian (Committee member) / School of Molecular Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2019-12
Description
Microsolvation studies have begun to shed the light on the impact that single water molecules have on the structure of a molecule. The difference in behavior that molecules show when exposed to an increasing number of water molecules has been considered important but remains elusive. The cluster distributions of formic acid were studied for its known importance as an intermediate in the water gas shift reaction. Implementations of the water gas shift reaction range from a wide range of applications. Studies have proposed implementations such as variety such as making water on the manned mission to mars and as an industrial energy source. The reaction pathway of formic acid favors decarboxylation in solvated conditions but control over the pathway is an important field of study. Formic acid was introduced into a high vacuum system in the form of a cluster beam via supersonic expansion and was ionized with the second harmonic (400nm) of a pump-probe laser. Mass spectra showed a ‘magic’ 5,1 (formic acid, water) peak which showed higher intensity than was usually observed in clusters with 1 water molecule. Peak integration showed a higher relative abundance for the 5,1 cluster as well and showed the increased binding favorability of this conformation. As a result, there is an enhanced probability of molecules sticking together in this arrangement and this is due to the stable, cage-like structure that the formic acid forms when surrounding the water molecule.
ContributorsQuiroz, Lenin Mejia (Author) / Sayres, Scott G. (Thesis director) / Mills, Jeremy (Committee member) / Biegasiewicz, Kyle (Committee member) / School of Molecular Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
The human gastrin receptor (CCKBR or CCK2R) is a class A G protein-coupled receptor (GPCR) found throughout the central nervous system, stomach, and a variety of cancer cells. CCK2R is implicated in the regulation of biological processes, including anxiety, satiety, arousal, analgesia, psychosis, and cancer cell growth and proliferation. While CCK2R is an attractive drug target, few drugs have managed to effectively target the receptor, and none have been brought to market. Contributory to this is the lack of high-resolution crystal structure capable of elucidating the binding regions of CCK2R to streamlining drug screening. While GPCRs are not amenable to traditional structural analysis methodologies, the advent of lipidic cubic phase (LCP) crystallography and serial femtosecond crystallography (SFX) at X-ray free electron lasers (XFELs), has extended the applicability of X-ray crystallography to these integral membrane proteins. LCP-SFX depends on optimizing the protein of interest for extraction, purification, and crystallization. Here we report our findings regarding the optimization of CCK2R suggesting the synergistic relationship between N-terminal truncations and the insertion of a fusion protein along ICL3, in addition to a 30-residue truncation of the C-terminus. Samples were expressed in Sf9 insect cells using a Bac-to-Bac baculovirus expression system, extracted using n-Dodecyl-β-D-Maltoside detergent, and purified via TALON immobilized metal-ion affinity chromatography. The constructs were characterized via SDS-PAGE, Western blot, and size exclusion chromatography. These findings demonstrate the improvements to CCK2R’s crystallographic amenability upon these modifications, however significant improvements must be made prior to crystallization trials. Future work will involve screening C-terminal truncations, thermostabilizing point mutations, and co-crystallizing ligands. Ideally this investigation will serve as a model for future CCK2R structural analysis and contribute to a heightened interest in CCK2R as a therapeutic target.
ContributorsStevens, Alexander Wade (Author) / Liu, Wei (Thesis director) / Chiu, Po-Lin (Committee member) / Mills, Jeremy (Committee member) / School of Human Evolution & Social Change (Contributor) / School of Molecular Sciences (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2019-05