770 research outputs found
Transition metal-catalyzed C-N and C-C bond formation: N-tert-prenylation and alkene hydroacylation
This thesis presents the development of new catalysts for the palladium-catalyzed N-tert-prenylation of indoles, the rhodium-catalyzed endo- and enantioselective hydroacylation of ortho-allylbenzaldehydes, studies toward the rhodium-catalyzed intramolecular hydroacylation of 1,2-disubstituted alkenes, and the first examples of the rhodium-catalyzed, enantioselective hydroacylation of 1,1,2-trisubstituted alkenes.
Chapter II discusses the development of three distinct protocols for the synthesis of N-tert-prenylindoles using indole, (η6-indole)Cr(CO)3, and indoline nucleophiles. These reactions occur in the presence of the same palladium catalyst prepared in situ from readily available precursors and require loadings of the palladium catalyst that are up to ten times less than required for previously reported direct N-tert-prenylations of indoles. These methods for palladium-catalyzed N-tert-prenylation generate N-tert-prenylindoles with a range of electronic character in high yields (up to 94%) with high tert-prenyl-to-n-prenyl selectivity (up to 12:1).
Chapter III describes the development of a rhodium catalyst for endo- and enantioselective hydroacylation of ortho-allylbenzaldehydes. A catalyst generated from [Rh(COD)Cl]2, (R)-DTBM-Segphos and NaBARF promotes the enantioselective hydroacylation reactions and minimizes the formation of byproducts from competitive alkene isomerization and ene/dehydration pathways. These rhodium-catalyzed processes generate the 3,4-dihydronaphthalen-1(2H)-one products in moderate-to-high yields (49-91%) with excellent enantioselectivities (96-99% ee).
Chapter IV describes studies toward the intramolecular hydroacylation of 1,2-disubstituted alkenes as well as the first examples of catalytic, enantioselective hydroacylation of 1,1,2-trisubstituted alkenes. The intramolecular hydroacylation of 1,2-disubstituted alkenes is facilitated by a cationic rhodium complex and generates the indanone products in high yields (up to 94%). However, the α-center is prone to epimerization and results in racemic mixtures of the bicyclic products.
In contrast, the rhodium-catalyzed intramolecular hydroacylation of 1,1,2-trisubstituted alkenes generates highly enantioenriched, polycyclic architectures. The DFT and mechanistic studies presented are consistent with a reaction pathway that includes intramolecular alkene hydroacylation and α-epimerization. This reaction sequence enables the hydroacylation of 2-(cyclohex-1-en-1-yl)benzaldehydes to form hexahydro-9H-fluoren-9-ones in moderate to high yields (68-91%) with high enantioselectivities (up to 99% ee) and diastereoselectivities (typically \u3e20:1)
Difference as identity in The other story and the 1993 Whitney biennial.
This paper explores issues of identity and difference in art and its institutions through a historiographic study of two landmark exhibitions, The Other Story: Afro-Asian Artists in Post-War Britain (1989) and the 1993 Whitney Biennial. These exhibits intended to bring recognition to a marginalized group of artists, but were largely seen in critical literature to have perpetuated the binary distinctions and terms of difference that originated and maintained that marginalization. In order to fully understand the historical significance of these two exhibitions, in terms of their critical aims and reception, this thesis examines the specific social contexts in which they took place. By examining contemporary critical responses to each exhibition, it also highlights common issues that prevented these exhibitions from being viewed as successes at the time they were staged. The limitations and contradictions inherent in art institutions will be explored in depth, since they appeared in the terms, narratives, and criteria that were used to frame and organize both exhibitions. In exposing them, this thesis claims that the framing conditions of the exhibitions prevented them from achieving their stated aims. Particular attention will also be paid to the problematic articulation of difference that manifested itself as a fetishization of difference or a burden of representation in The Other Story and the 1993 Biennial. Kobena Mercer used the term burden of representation in 1990 to refer to the expectation placed on black artists, and exhibitions about black artists, to stand as representative of a cultural group or its contributions. In The Other Story and the 1993 Biennial, this burden is placed on the exhibitions as a whole and the artists featured, not only to represent black art, but the art of other marginalized groups as well, and this burden leads to the reification and fetishization of external difference. These two products of the articulation of difference are related and, in these exhibitions, serve to perpetuate binary distinctions, limit interpretations of artworks, reduce complex social problems, and affect the understanding of the exhibitions and the artists they feature. Finally, this thesis explores the historical legacy of these two exhibitions and relates the questions of identity and difference they illuminate to broader struggles for cultural pluralism at the end of the twentieth century
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Domestic violence and physical child abuse: Do social workers see the risk?
The purpose of the study was to look at whether domestic violence is being viewed as a risk factor in homes where there is also physical child abuse. Historically a misconception has existed that child abuse occurs in a vacuum of sorts, isolated from other family problems
Twelve Tips for Optimising Medical Student Fitness to Practise
Fitness to practise processes are in place to safeguard patient safety
and maintain professional standards. This Twelve Tips article provides
context to medical student fitness to practise in the UK and situates
process under the regulator and the university. The Tips examine
some of the dichotomies and pitfalls in an increasingly litigious field
and provide operational recommendations. The authors draw on their
experience across several medical schools and highlight some of the
complexities at play. Fairness through diverse panel constituency, and
education and training for panel members are highlighted. The
potential impact of mental health diagnoses on outcomes is
considered, alongside the need for support for practitioners involved
in this high-stakes process. The tips outlined are broadly transferable
to other regulated programmes nationally and internationally and link
to postgraduate practice. The authors hope to ignite a dialogue in an
area with limited benchmarking and literature
Factors Influencing Post - High School Graduation Plans Of Students Enrolled In Food Service-Related Courses At California Regional Occupation Centers/Programs (Career Selection, Occupational Choice, Vocational)
Purpose: The purpose of this study was to determine the degree of influence from various factors on a student\u27s decision to enroll in a food service-related course and whether these factors were affected by post high school graduation plans.
Procedure: Sixty-nine percent of the Regional Occupational Centers/ Programs teachers and one section of students instructed by each teacher completed the survey instruments. The questionnaire items queried the respondents concerning demographic information as well as the degree of influence of various person- and job-related factors.
Findings and Conclusions: Results of this investigation revealed that the responding student population had a strong interest in pursuing higher education. The major obstacle to enrollment for the non-college bound population was not discovered. Grade point average, course requirements and money were found to be perceived as not limiting their college enrollment.
The teacher population rated the influence of various factors differently for six of 19 items and generally higher than the student group. The two populations were generally congruent with respect to the relative order placement of the factors. White and minority populations evaluated the importance of most factors differently from one another . The two gender groups noted some of the influencing factors differently. White and male populations indicated the greatest propensity toward higher education.
Most vocational students intend to seek employment in the food service field. The teacher population tended to view students as being primarily job oriented. Vocational program students need to be informed about and, if appropriate, encouraged to pursue higher education. Vocational programs often enroll a disproportionate share of females and minority populations. Attainment of higher education by these group may serve as a vehicle for upward mobility. Students perceive satisfaction with the decision to enroll and with school in general if they note the applicability and relevance of the material they study.
Recommendations: 1) Replicate the study using various vocation program students and nationwide to determine the consistency and generalizability of these results. 2) Conduct a follow-up study to determine the rate of actualization of college and job seeking plans. 3) Investigate the discrepancies between teacher and student populations relative to influencing factors and post-graduation plans to determine the sources of these differences
Who’s Taking the Accounting Class? Leveraging Professional Skepticism While Teaching Accounting Online
The shortage of academically qualified accounting professors makes this a relevant time to increase the use of online tools for content delivery, assignment completion and assessment. Accounting students employed as teaching assistants (TA) can develop professional skills including skepticism, problem solving, analysis, organization and electronic documentation, while in academia. Certified Public Accountants (CPA) and educators are held accountable to high ethical standards through a code of conduct and academic integrity policies. This teaching case incorporates ethical decision making from an experience in an online virtual classroom where power differentials and analysis of student activity require research in a learning experience
Evaluating the Impact of Aurora Kinase Inhibition on Immunogenic cell death(ICD) in HPV+ murine models
https://openworks.mdanderson.org/sumexp23/1109/thumbnail.jp
No effect of tart cherry juice or pomegranate juice on recovery from exercise-induced muscle damage in non-resistance trained men
Tart cherry juice (TC) and pomegranate juice (POM) have been demonstrated to reduce symptoms of exercise-induced muscle damage (EIMD), but their effectiveness has not been compared. This randomized, double-blind, parallel study compared the effects of TC and POM on markers of EIMD. Thirty-six non-resistance trained men (age 24.0 (Interquartile Range (IQR) 22.0, 33.0) years, body mass index (BMI) 25.6 ± 4.0 kg·m−2) were randomly allocated to consume 2 × 250 mL of: TC, POM, or an energy-matched fruit-flavored placebo drink twice daily for nine days. On day 5, participants undertook eccentric exercise of the elbow flexors of their non-dominant arm. Pre-exercise, immediately post-exercise, and at 24 h, 48 h, 72 h and 96 h post-exercise, maximal isometric voluntary contraction (MIVC), delayed onset muscle soreness (DOMS), creatine kinase (CK), and range of motion (ROM) were measured. The exercise protocol induced significant decreases in MIVC (p 0.001; max decrease of 26.8%, 24 h post-exercise) and ROM (p = 0.001; max decrease of 6.8%, 72 h post-exercise) and significant increases in CK (p = 0.03; max increase 1385 U·L−1, 96 h post-exercise) and DOMS (p 0.001; max increase of 26.9 mm, 48 h post-exercise). However, there were no statistically significant differences between treatment groups (main effect of group p > 0.05 or group x time interaction p > 0.05). These data suggest that in non-resistance trained men, neither TC nor POM enhance recovery from high-force eccentric exercise of the elbow flexors
Psychological Impact on Parents of an Inconclusive Diagnosis Following Newborn Bloodspot Screening for Cystic Fibrosis: A Qualitative Study.
Genetic results of uncertain clinical significance are being returned to parents following newborn screening, representing a paradigm change in how society considers health and illness. 'Cystic Fibrosis screen positive, inconclusive diagnosis' (CFSPID) is a designation given to newborns with a positive screening result for, but not a definitive diagnosis of, cystic fibrosis. We explored the psychological impact of receiving a CFSPID result on parents. Five semi-structured interviews were conducted with eight parents whose children have CFSPID. Interpretative phenomenological analysis identified these themes: "The way we were told": 'diagnosis as a traumatic event' focused on how parents were distressed and dissatisfied by the initial screening result communication, 'Facing and challenging traditional ideas about health and illness' explored the emerging problem of how CFSPID does not fit the commonly accepted medical model, and 'Making certainty out of uncertainty' explored the varying strategies parents developed to adapt to the uncertainty regarding their child's prognosis. Findings suggest that CFSPID results caused parents' distress, initiated with the first communication of the result and persisting thereafter. Our data suggests approaches to the delivery of CFSPID results that may reduce the impact. Work is needed to close the gap between healthcare advances and societies commonly held medical model
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