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Scope and Mechanism of the Ruthenium-Catalyzed sp\u3csup\u3e3\u3c/sup\u3e C–H Coupling Reaction of 2-Alkylindoles with Enones for the Synthesis of Carbazole Derivatives
No full textThe catalytic system consisting of a cationic Ru–H complex 1 and 3,4,5,6-tetrachloro-1,2-benzoquinone (L1) was found to be highly effective for the dehydrative sp3 C–H coupling reaction of 2-alkyl substituted indoles with enones to form 2,4-disubstituted carbazole products. The analogous coupling reaction of 2-alkylindoles with linear enones bearing the cyclic olefinic group afforded tetracyclic carbazole products. A normal deuterium kinetic isotope effect was measured from the coupling reaction of 1,2-dimethylindole versus 1-methyl-2-(methyl-d3)indole with (E)-3-penten-2-one (kH/kD = 2.5). The Hammett plot was constructed from the reaction of para-substituted indoles 5-X-1,2-dimethylindole (X = OMe, Me, H, F, and Cl) with 4-phenyl-3-buten-2-one (ρ = −1.6 ± 0.2). The density functional theory (DFT) calculations were performed to obtain a complete energy profile for the coupling reaction. The combined experimental and DFT computational data revealed a detailed mechanistic path that features an initial coupling of indole and enone substrates, the turnover-limiting heterolytic sp3 C–H activation step, and the subsequent cyclization and dehydration steps. The catalytic method provides an efficient synthesis of carbazole derivatives from the dehydrative sp3 C–H coupling reaction of readily available indole with enone substrates without employing any reactive reagents or forming wasteful byproducts
An Evaluation of a US College Student-Athletes’ Peer Support Training Program: A Pilot Project
Full text linkPurpose
This pilot project aims to evaluate the effectiveness of peer support competency training in relation to college student-athletes’ peer support skills and well-being.
Design/methodology/approach
This project included four 90-min training sessions on peer support competency skills based on the Substance Abuse and Mental Health Services Administration’s peer support core competencies guidelines. A mixed-method design was used to evaluate the effectiveness of the training by measuring their peer support ability and through focus groups to gain insight into their experience.
Findings
A two-way analysis of variance yielded a significantly higher well-being score at the posttraining. Qualitative data revealed an increased sense of connection during the training period among participants.
Research limitations/implications
This pilot project had several limitations for generalization. This pilot project consisted of a small sample size, and most of the athletes were recruited from track and field, soccer, lacrosse and cross country. Ongoing peer support program evaluation and future research with student-athletes with diverse backgrounds is essential to promote student-athletes’ mental health.
Practical implications
Peer support or peer educator program in the athletics department represents an opportunity for universities to provide an accessible mental health resource for student-athletes. To ensure the effectiveness of the peer support program, it is important that mental health professionals in the athletics department provide basic trainings for members in empathy listening skills, self-compassion, coping strategies and mental health resources.
Social implications
Group experiential training could increase peer support efficacy and strengthen a sense of community. Because peer support programs are not counseling or therapy programs, it allows easy access to mental health support for student-athletes.
Originality/value
This work has not been submitted elsewhere or under consideration by any other publication. The authors report there are no competing interests to declare
Nursing Perspective Regarding the Stigma Associated With Disability
Full text linkThe “Gendered Disabilities” project is an attempt to shed the light on the support needed for families caring for persons with disabilities, in general, and Muslim families caring for persons with disabilities, in particular. Without a doubt, stigma plays a major role in the ways in which different sociocultural groups experience disability. Therefore, understanding stigma as related to disability will help the health care professionals include strategies to reduce stigma and health disparities within minority communities
Disabilities Project Initial Report
Full text linkThis report describes the processes, aims, and outcomes of the Disabilities Digital Archive, a project conducted as part of Arab and Muslim Women’s Research and Resource Institute’s vision to create data and oral histories regarding women’s experiences and transform them into meaningful information. To this end, this project seeks to explore gendered disability and facilitate more complex understandings of disability at the intersection of gender, culture, immigration, and other modes of identity. By collecting data from Muslim community members in Milwaukee, including people with differences of ability and their families, caregivers, Imams and religious scholars, community organization leaders, and health care/mental health professionals, it presents a fuller picture to break down stigma and increase access to resources for people with differences of ability
COMPARISON OF SHEAR BOND STRENGTH OF NEW AND REBONDED SYMETRI™ CLEAR CERAMIC BRACKETS
Full text linkObjective: The purpose of this study was to compare the shear bond strength of the Symetri™ Clear brackets bonded initially to enamel versus after rebonding. An additional aim was to see how a generic debond pliers compares to the Symetri™ Debonding pliers in terms of shear bond strength and bracket morphology after debond. Methods: Sixty extracted premolars and nine extracted canines were collected and stored in 1% Chloramine T solution. The canines were used for a pilot study to test methodology. The premolars were randomly assigned to one of three Groups: Group 1 (single bond), Group 2A (debond with Symetri™ pliers) and Group 2B (debonded with generic pliers). Premolars from Group 2A & 2B were prepared for bonding using the manufacturer\u27s protocol: cleaned with prophy paste, etched using 37% phosphoric acid, rinsed with water, and air dried. Ortho Solo primer was applied to the enamel surface before the bracket was bonded using Blugloo adhesive. Teeth were then mounted and stored in distilled water at 37oC. Forty-eight hours later, brackets from Group 2A & 2B were debonded using their designated pliers, Symetri™ or generic. Adhesive was removed from the enamel surface using a dental handpiece and a 12-fluted carbide finishing bur and bracket was cleaned using 90 grit aluminum oxide air-abrasion. Brackets were then rebonded to the same teeth at the same time as bonding Group 1 using the above protocol. Premolars from Group 1 were then mounted. All teeth were stored in distilled water for forty-eight hours before using the universal testing machine to test shear bond strength. After the final debond, premolars were evaluated using a microscope to score Adhesive Remnant Index (ARI) to help identify where the bond failure occurred. Results: There were no significant differences in shear bond strength (ANOVA; P\u3e0.05) between Groups 1, 2A, and 2B. ARI scores for Group 1 were significantly lower than Group 2A and 2B (Kruskal-Wallis and Pairwise Comparisons with the Bonferroni Correction; P\u3c 0.05). Conclusions: There was no statistically significant difference in shear bond strength between the initial bonding and rebonding of Symetri™ Clear brackets, nor did the type of debonding pliers used have an impact on bond strength. Bond failure during the initial debond typically occurred within the adhesive layer, whereas subsequent failures more commonly occurred at the adhesive–bracket interface
COMPARISON OF LEVELING A DEEP CURVE OF SPEE WITH EXTRACTIONS VERSUS NON-EXTRACTION: A BIOMECHANICAL PERSPECTIVE
Full text linkIntroduction: This study evaluated and compared orthodontic forces from different archwire designs and materials used to correct a deep curve of Spee. Methods: A three-dimensional orthodontic force tester (OFT) was used to measure forces and moments exerted by archwires on brackets from central incisors to first molars. Two setups were tested: one with a full dentition from central incisor to first molar, and another simulating bicuspid extractions with the first premolar removed. Dentoform models representing a deep curve of Spee were created using cone-beam computed tomography (CBCT) data. The setup employed 0.022 × 0.028-inch zero-prescription brackets secured with elastomeric ligatures. Three types of 0.016 × 0.022-inch archwires were tested (n = 10 per group): reverse curve of Spee nickel-titanium (rNiTi), stainless steel with step-down bends (SSSD), and titanium-molybdenum alloy with step-down bends (TMASD). The rNiTi wires had a preformed reverse curve, while SSSD and TMASD included bilateral 1.0-mm step-down bends between the canine and lateral incisor and between the lateral and central incisor. Analysis of variance (ANOVA) evaluated the effect of wire design and material on the magnitude and direction of forces and moments on incisors and molars, with p \u3c 0.05 considered statistically significant. Results: Among the archwires tested, the lowest intrusive force occurred with non-extraction rNiTi (2.06 N), while the highest was seen in the extraction SSSD group (2.23 N). First molars experienced intrusive forces in the extraction setup (0.003–0.006 N) and extrusive forces in the non-extraction setup (–0.02 to –0.07 N). The rNiTi archwire produced the greatest buccal-crown moment on the lateral incisors (6.11–6.22 Nmm), followed by SSSD, with TMASD generating the least. Molars exhibited buccal-crown moments ranging from 0.88 to 1.31 Nmm across all tests. In the extraction scenario, rNiTi created a 3.2 Nmm lingual-crown moment on the second premolar, while TMASD produced a –0.71 Nmm buccal-crown moment in the non-extraction setup. Conclusions: Force distribution varied across all archwires. Material, wire size, and severity of overeruption significantly influenced tooth loading, particularly in buccal-lingual moments. The most notable difference occurred on the second premolar between extraction and non-extraction setups. Although varying archwire materials are expected to behave differently, in vivo studies are needed to compare the efficiency and efficacy of Curve of Spee leveling
Fundamental Exploration of Soot Formation and Morphology from A Molecular Modeling Perspective
Full text linkSoot formation remains one of the least understood phenomena in combustion science, posing significant challenges due to its complex physicochemical nature and considerable environmental and health impacts. This dissertation presents a comprehensive molecular-level investigation into the fundamental mechanisms governing soot inception, particle growth, and morphological evolution through state-of-the-art reactive molecular dynamics (RMD) simulations of acetylene pyrolysis. A novel computational analysis utility, Molecular Arrangement and Fringe Identification and Analysis from Molecular Dynamics (MAFIA-MD), was developed to accurately characterize soot particle formation, providing detailed insights into chemical composition, internal structure, and surface characteristics. Critical physicochemical markers defining the boundary between gas-phase species and particulate soot were rigorously identified, including specific primary particle mass and number of carbon atoms. Extensive analyses of internal structural evolution revealed essential insights into particle density variations, radial distribution of internal features, and structural complexity during soot nucleation and growth. Furthermore, detailed characterization of soot particle pore structures and surface morphology established quantitative relationships among morphological features, fractal dimensions, and particle reactivity, significantly enhancing predictive capabilities of engineering scale models. This dissertation effectively addresses critical gaps in current knowledge by providing robust methodologies and extensive molecular-level insights that substantially advance our understanding of soot formation processes. The outcomes of this research offer essential contributions towards refining predictive combustion models and developing targeted strategies for emissions control, thereby supporting cleaner combustion technologies, improved public health, and environmental sustainability
Constancy, Tristram, and the “Parcell” of \u3cem\u3eThe Faerie Queene\u3c/em\u3e Book VII
No full textSpenser’s Mutabilitie Cantos appeared to their first printer as “parcell of some following Booke of the Faerie Queene, Vnder the Legend of Constancie.” This essay imagines a Legend of Constancy, a Book VII that would continue The Faerie Queene’s consistent pattern of differentiating human from faerie virtues, with the former involving virtue more in discursive reasoning. The Cantos have signs of a philosophical digression pertinent to Constancy, a discursive virtue conducive to partitioning (as fidelity, perseverance, and perspective); they also have ligatures to Tristram in Book VI, canto ii, who, as an adaptation of Malory, is superbly qualified as a human Knight of Constancy