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Preparation of Gamma-Lactams via a Nickel-Catalyzed Addition of In Situ Generated Diorganozinc Reagents to Imides
No full textA range of .-hydroxy-lactams have been prepared from the selective direct addition of in-situ prepared diorganozinc nucleophiles to N-substituted aryl phthalimides with catalytic amounts of Ni(COD)2 and PPh3.
A wide range of substituted phthalimides and diarylzinc nucleophiles varying in electronic character have been prepared by condensation and lithium-halogen exchange reactions respectively. Diarylzinc reagents were added directly to the N-phenyl phthalimide without purification. The preparation of imides and nucleophiles is shown below: (see abstract book for image
Toward a (bis)Trifluoromethyl-Substituted Quinazolinespirohexadienone(QSHD) Photochrome for Gating PICT
No full textIn order to gate photoinduced charge transfer (PICT), photochromes need to be able to undergo an isomerization from a short wavelength (SW) form to a long wavelength (LW) form when exposed to UV light, and only revert back thermally. Gating of PICT is accomplished when the LW form has increased conjugation so that it can accept an electron more easily than the SW form. Synthetic steps have been taken to make the LW form more reducible while keeping the ground state reduction potential (Eºred) of the SW relatively unchanged. One of these steps has been the synthesis of a trifluoromethyl-substituted derivative of the QSHDs in which the electron withdrawing properties of the trifluoromethyl groups make the LW form more reducible. Due to the electron withdrawing effects of the trifluoromethyl groups, synthesis of the desired photochrome cannot be accomplished in the same way as past QSHDs. An improved method has been implemented using aryl iodides and bromides. Predicted reduction potentials of the target photochrome, synthesis using the halides thus far, and possible synthetic routes toward replacing the halides with trifluoromethyl groups are presented
Carbon-Carbon Single Bond Activation for Nucleophilic Addition to Michael Acceptors
Get PDFIntramolecular alkene carboacylation has previously been achieved under rhodium catalysis using quinolinyl ketones. Utilizing insight gained from mechanistic studies, new substrates containing ortho-substitution have been prepared and subjected to rhodium catalysis with an exogenous alkene. This research provides an overview of substrate synthesis as well as the unexpected product—rather than the anticipated carboacylation these substrates have been observed to undergo carbon-carbon bond activation followed by conjugate addition to Michael acceptors
Validating the Unidimensional Relationship Closeness Scale Through Behavioral Indicators
Get PDFThe Unidimensional Relationship Closeness Scale (URCS; Dibble, Levine, & Park, 2012) is a new measure of relationship closeness. The purpose of this study is to provide additional construct validation for the measure by determining whether the scale predicts closeness-related behaviors. For example, closeness and physical proximity are positively related. This study tests the proposition that higher scores on the URCS will correspond with shorter distances between two participants. After completing the URCS, participants will engage in a short dyadic conversation with either a friend or a stranger. The distance between the participants’ chairs will be measured. These interactions will be videorecorded, and the videos will be coded for verbal and nonverbal indicators of closeness (e.g., body orientation, eye contact). To the extent that URCS scores predict behavioral indicators of closeness, more confidence can be placed in the measure
Proposing Genes for Gap Reactions in Metabolic Pathways
Get PDFA metabolic model is a map of the biochemical reactions that take place in an organism. These reactions are catalyzed by enzymes, which are encoded by genes in the organism’s genome. However, there are reactions that are known to exist and needed to complete the metabolic model, but are not associated with any genes. These are called “gap reactions”. Our goal is to find the genes that encode the enzymes that catalyze these gap reactions. We have researched two approaches: a knowledge-driven approach that focuses on finding a small set of good candidates, and a data-driven approach that focuses on scoring all candidates to rank their plausibility. Identifying the genes that are associated with gap reactions produces better predictive models and directs laboratory experimentation
The Effect of Public Lands on Property Taxes in Minnesotan Counties
No full textAbout twenty-five percent of Minnesota land is publicly owned, much of it resulting from private owners failing to pay taxes on their landholdings during the Great Depression. There has been a longstanding debate about whether continued public ownership or private ownership would generate a heavier tax burden for county residents. This paper investigates whether or not public land ownership affects the county tax rate by comparing total tax levies with the proportion of publicly owned land in Minnesotan counties. By using a series of linear regressions, I found that public ownership of land did not cause a significant increase or decrease in the tax levies of county inhabitants. While there was no significant correlation between tax levies and the proportion of publicly owned land within a county, the income level and distance away from Minneapolis were found to have a significant impact on the tax levies of Minnesotan counties. While my findings affirm results from previous studies, the complexities of the situation allow for ample future research possibilities
Surface Stimulation to Alleviate Phantom Limb Pain: Waveform to Elicit Tapping
No full textPhantom limb pain occurs to some degree in 50-80% of amputees with no known successful treatments. The overall goal of this project is to use surface electrical stimulation to alleviate phantom limb pain. A leading hypothesis suggests that cortical reorganization (the remapping of the somatosensory cortex) could lead to phantom limb pain. To potentially reverse this, the median and ulnar nerves will be stimulated in hopes of keeping their respective regions in the cortex receiving information from the hand. Previous work has found that reliable sensation could be obtained in the hand using electrical stimulation of nerves at the elbow, but that it most often felt like ‘tingling’ or ‘buzzing’. In an attempt to evoke natural sensation, two stimulation types were created. After preliminary testing, both stimulation types produced a tapping sensation. Both forms of stimulation were found to be more pleasant than standard, non-modulating stimulation. Future work will include comparing the two stimulation types and deciding which produces the most natural sensation
Shedding Light on Illuminated Manuscripts of the Anglo-Saxon Age: An Investigation into the Life and Illustrations of J.R.R. Tolkien
Get PDFFor decades, the work of J.R.R. Tolkien has fueled investigations in medieval studies due to his incorporation of Anglo-Saxon themes in his writing. A fact unbeknownst to some readers is that Tolkien was also an avid artist, and the illustrations that accompany many of his pieces are evidence of how medieval culture influenced his life. The scope of this research project includes gaining a general understanding of the Middle Ages, as well as a history of Anglo-Saxon manuscripts and their illuminators. This paper will explore Tolkien’s inspirations as a writer and artist, and conclude with a comparison of his illustrations to manuscript illuminations. After dissecting these pieces, it is clear that Tolkien’s technique, context, style, and content were influenced by the work of medieval artists and writers
The Tolkien Guide to the Literary Phenomenon of Fan Fiction
Get PDFAs the Internet is playing an increasing role in our lives and consciousness, literary scholars are now entering the conversation on how technology has impacted the way we think about and experience literature. New trends in digital literature such as the extraordinarily popular phenomenon of fan fiction—web-based fiction written by amateur fan-authors who build upon already established characters, settings, and plotlines—have created quite the controversy, causing us to re-examine many concepts, from the roles of readers and writers in the creative process to how we define literature itself. Does fan fiction have a place in the literary world or is it merely another new craze of popular culture? In my theoretical inquiry into fan fiction, I apply a framework of analysis developed by J.R.R. Tolkien in his study of fairy stories which may serve to point out the potential of this new digital literacy and address some key concerns involved in an in-depth investigation of fan fiction
Integration Before Integration: How World War II Exploded Diversity in Baseball
Get PDFAlthough Jackie Robinson became the first African American to play Major League Baseball in April 1947, he was not the first nonwhite person to play the sport. Latinos and Native Americans preceded Robinson, and some even before the 20th century. The opportunity to play particularly opened up in World War II, when legends like Bob Feller, Hank Greenberg, and Stan Musial left at the peaks of their careers to serve overseas. Players like 15-year old Joe Nuxhall, one-armed outfielder Pete Gray, and a number of Latinos and Native Americans debuted at this time. Thirteen out of sixteen Major League teams had a non-American born Latino on their roster during World War II. Adrian Burgos, professor of history at University of Illinois, highlights 57 Latinos who played before Robinson, and more than a third of whom played from 1941-1945. The gap created by white players serving overseas led to opportunity. As a continuation of research on Native American baseball players conducted at the National Baseball Hall of Fame and Museum, I look at statistics, roster transactions, and periodicals to highlight four Native American players and four Latinos. Their movement into the Major Leagues was directly linked to the crisis precipitated by World War II. Though many had short professional careers, they were trailblazers and exemplars for future foreign and nonwhite players. After World War II, owners and general managers were not as reluctant to sign foreign nonwhite players. This put American baseball on the path to becoming the world’s most diverse professional sport