6,477 research outputs found
Halting a Runaway Train: Reforming Teacher Pensions for the 21st Century
Full text linkWhen it comes to public-sector pensions, writes lead author Michael B. Lafferty in this report, "A major public-policy (and public-finance) problem has been defined and measured, debated and deliberated, but not yet solved. Except where it has been." As recounted in "Halting a Runaway Train: Reforming Teacher Pensions for the 21st Century", these exceptions turn out to be revealing -- and encouraging
Michael Mark Papers
No full textMichael Mark (b. 1936) is an American music educator and author. He received his degrees in music from Catholic University (BM 1958 and DMA 1969), George Washington University (MA 1960), and the University of Michigan (MM 1962). During his career, Mark was employed by public school systems and universities in Maryland, Washington, D.C., and New York. As an author he has published numerous books and articles on music education, frequently on the history of that topic. This collection consists of educational materials, correspondence, writings, newspaper clippings, photographs, books, recordings, and scores related to his career as an educator and author
Bernard Williams
No full textAn edited multi-author volume assessing the moral philosophy of the late British philosopher Bernard Williams. Contributors: Adrian Moore, John Skorupski, Alan Thomas, Robert B Louden, Michael Stocker, A. A. Long, Edward Crai
Postmodern Theory and the Choreography of Michael Clark
No full textThis study addresses two interrelated questions: Can postmodern ‘theory’ illuminate an understanding of Michael Clark’s work? and, a sub-question, In which ways, if at all, does Clark’s work demonstrate a postmodern sensibility? Chapter one, the introduction to this study, provides a ‘portrait’ of postmodernism, that is, it addresses the question What is postmodernism? Chapter two is a biography of Michael Clark. The seminal sections to this study, however, are chapters three and four. Here the author blends a discussion of a) subject matter, treatment and meanings in Clark’s choreography, b) journalistic criticisms of those features of his work, and c) postmodern theory. The outcome of these chapters is to demonstrate that Clark’s works do indeed require re-interpretation and re-evaluation, and to illustrate how these factors might be achieved
On the Michael addition of water to C = C bonds
No full text?-Hydroxy carbonyl compounds are an important class of compounds often found as a common structural motif in natural products. Although the molecules themselves look rather simple, their synthesis can be challenging. Water addition to conjugated C = C bonds opens up a straightforward route for the preparation of ?-hydroxy carbonyl compounds. Moreover, water addition to C = C bonds benefits a lot from its simplicity and excellent atom economy. However, the enantioselective addition of water to ?,?-unsaturated carbonyl (Michael) acceptors still represents a chemically very challenging reaction, due to the poor nucleophilicity of water and its small size, which make regio- and stereoinduction difficult. Equally, the often unfavorable equilibrium of water-addition reactions remains to be solved. In contrast, enzymes such as fumarase, malease, citraconase, aconitase, and enoyl-CoA hydratase have been successfully used on industrial scale, and their excellent (enantio-) selectivities are highly valued. Unfortunately, most hydratases are part of the primary metabolism where perfect substrate specificity is required. This very high substrate selectivity severely limits their practical applicability in organic synthesis. Thus, a straightforward approach with broad applicability still had not been described. The aim of the research presented in this thesis was to take up this challenge and dedicated to the search for a Michael hydratase with a more relaxed substrate specificity for the preparation of important ?-hydroxy carbonyl compounds. The stereospecificity of enzyme-catalysed reactions has been a fruitful source of information about the mechanisms of enzyme catalysis and vice versa; the application of stereospecifically labelled substrates allows for studying the course of the reaction. It offers a very promising opportunity to comprehensively understand the precise mechanistic and kinetic details of even the most complex enzymatic reactions. Thus Chapter 1 provides unifying ideas for stereochemistry of the enzymatic water addition to C = C bonds. This enhances our understanding of the chemistry of water addition to C = C bonds, and further allows us to find more hydratases from natural sources or obtained via protein engineering. In Chapter 2, a direct, enantioselective Michael addition of water in water to prepare important ?-hydroxy carbonyl compounds using whole cells of Rhodococcus strains is described. Good yields and excellent enantioselectivities were achieved with this method. This opens up an entirely new approach for the preparation of important ?-hydroxy carbonyl compounds. Deuterium labelling studies demonstrate that a Michael hydratase catalyzes the water addition exclusively with anti-stereochemistry, which belongs to the family members of hydratases: oleate hydratase, fumarase, malease, aconitase and type II dehydroquinase with a preference for the anti-addition; whereas, type I dehydroquinase, enoyl-CoA hydratase and artificial hydratase exclusive prefer for the syn-addition, as discussed in Chapter 1. The biocatalytic reaction system was carefully optimized for gram-scale synthesis, resulting in good conversions and excellent enantioselectivities. Under the optimized conditions, whole cells could be reused for 4 cycles without significant loss of activity while maintaining up to 90% ee. Since whole cells from Rhodococcus strains were used to catalyse the Michael addition of water in water to a series of ?,?-unsaturated carbonyl compounds, and when the work presented in Chapter 2 started, no genomic information of Rhodococcus strains was publically available, we sequenced and annotated the strain R. rhodochrous ATCC 17895. This is described in Chapter 3 together with features of the R. rhodochrous ATCC 17895. It is a Gram-positive aerobic bacterium with a rod-like morphology. The 6,869,887 bp long genome contains 6,609 protein-coding genes and 53 RNA genes. Our study suggests the Michael hydratase has not been described before. In the work presented in Chapter 2, we found that most ?-hydroxy ketones are not commercially available or commercially expensive as we mentioned in the first paragraph, which made the stereoselectivity determination of Michael addition products difficult. Indeed, many seemingly simple molecules have to be prepared via multi-step syntheses, in particular so if they are optically active. Therefore a straightforward approach to enantiomerically enriched (R)- and (S)-3-hydroxycyclopentanone was established by kinetic resolution in Chapter 4. This methodology allows us to prepare more ?-hydroxy carbonyl compounds structurally closely related to 3-hydroxycyclopentanone. The isolated chiral alcohols were used to determine the stereochemistry of the Michael addition of water in Chapter 2, saving us a lot of laboratory work. Moreover, unexpected stereoselective reduction of conjugated C = C bonds was discovered during studies on the enantioselective Michael addition of water. As mentioned in Chapter 2, the whole cells of R. rhodochrous ATCC 17895 reduced ?,?-unsaturated cyclic ketones into the corresponding ketones as initially undesired side reaction for the addition of water to C = C bonds. Therefore, ene-reductase activity was also investigated in Chapter 5. A series of substrates, including activated ketones, aldehydes, amines and nitro-compounds were screened for ene-reductase activity using whole cells of R. rhodochrous ATCC 17895. This showed that R. rhodochrous is a very promising catalyst for the reduction of C = C bonds and harbours ene-reductases. Indeed, looking for the annotated ene reductase from the genome of R. rhodochrous ATCC 17895 as described in Chapter 3, three candidates were observed and were classified as ene-reductases by amino acid sequence alignment with the known Old Yellow Enzymes (OYEs). Thus, the putative ene-reductase genes from R. rhodochrous ATCC 17895 were heterologously overexpressed in Escherichia coli and one of the encoded proteins was purified and characterized for their biocatalytic and biochemical properties. Based on these accomplishments it can be concluded that we have discovered a new Michael hydratase and three new ene reductases from Rhodococcus strains. Genome sequence and annotation of strain R. rhodochrous ATCC 17895 has been done, offering an excellent opportunity for the discovering novel enzymes, for instance, the Michael hydratase and S-selective ene reductase. The important chiral ?-hydroxy carbonyl compounds can be prepared by kinetic resolution of racemic alcohols using lipases or the direct enantioselective Michael addition of water using whole cells of Rhodococcus strains. The isolated products from kinetic resolution were readily used for the stereochemistry determination of Michael addition of water in water, completes the story of water addition to C = C bonds.BiotechnologyApplied Science
Conversations with Michael Chabon
No full textSince the publication of his first novel, The Mysteries of Pittsburgh, launched him to fame, Michael Chabon (b. 1963) has become one of contemporary literature\u27s most acclaimed novelists by pursuing his singular vision across all boundaries of genre and medium. A firm believer that reading even the most challenging literature should be a fundamentally pleasurable experience, Chabon has produced an astonishingly diverse body of work that includes detective novels, weird tales of horror, alternate history science fiction, and rollicking chronicles of swashbuckling adventure alongside tender coming-of-age stories, sprawling social novels, and narratives of intense introspection. Uniting them all is Chabon\u27s utterly distinct prose style--exuberant and graceful, sometimes ironic but never cynical. His work has earned accolades ranging from the Pulitzer Prize to science fiction\u27s Hugo and Nebula Awards. Conversations with Michael Chabon collects eighteen revealing interviews with the renowned author of The Amazing Adventures of Kavalier & Clay, The Yiddish Policemen\u27s Union, and other much-admired works. Spanning nearly twenty years and drawn from science fiction fan magazines and literary journals alike, these interviews shed new light on the central concerns of Chabon\u27s fiction, including the importance of dismantling the false divide between literary and lowbrow, his evolving relationship to Jewish culture and literature, the unique properties of male friendship, and the complexities of race in contemporary America. These interviews are essential reading for anyone seeking a better understanding of the life and work of an author who has been instrumental in defining the landscape of contemporary American fiction.https://repository.lsu.edu/facultybooks/1144/thumbnail.jp
The persistence of a relative Rabinowitz-Floer complex
Full text linkWe give a quantitative refinement of the invariance of the Legendrian contact homology algebra in general contact manifolds. We show that in this general case, the Lagrangian cobordism trace of a Legendrian isotopy defines a DGA stable tame isomorphism which is similar to a bifurcation invariance-proof for a contactization contact manifold. We use this result to construct a relative version of the Rabinowitz-Floer complex defined for Legendrians that also satisfies a quantitative invariance, and study its persistent homology barcodes. We apply these barcodes to prove several results, including: displacement energy bounds for Legendrian submanifolds in terms of the oscillatory norms of the contact Hamiltonians; a proof of Rosen and Zhang\u27s non-degeneracy conjecture for the Shelukhin--Chekanov--Hofer metric on Legendrian submanifolds; and, the non-displaceability of the standard Legendrian real-projective space inside the contact real-projective space.Version 4 is substantially longer than prior versions because many details have been added (including new appendices A and B), as well as multiple explanatory figures. The conditions for Theorem 1.8 on interlinkedness have been correcte
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