Publications by authors named "R A Hein"

The molecular confinement within rigid macrocyclic receptors can trigger catalytic activity and steer the selectivity of organic reactions. In this work, the dimerization of methylcyclopentadiene (MCPD) isomers in the presence of cucurbit[7]uril (CB7) was found to display, besides a large rate acceleration, a striking regioselectivity in aqueous solution at pH 3, different from the thermodynamic products predominating in the absence of the supramolecular catalyst. Among the different possible regioisomers and diastereomers, the endo-3,7-dimethyl-3a,4,7,7a-tetrahydro-1H-4,7-methanoindene adduct was selectively formed, which is otherwise found only as a minor product in the dimerization of neat MCPD or in commercial dimeric mixtures.

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Introduction: We examined youth and young adult access to flavored vaping products following New York's (NY's) flavored vaping product sales restriction in 2020.

Method: In 2021, we conducted an online survey (N = 493) and focus groups (N = 33) with NY youth and young adults who vaped in the past year (ages 15-24). We summarize findings and use logistic regression to assess associations with access to flavored vaping products.

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Article Synopsis
  • The study focuses on the growing elderly population with atrial fibrillation (AF) and examines the effectiveness of AF ablation as a treatment for this group.
  • It analyzes data from Danish administrative records from 2001 to 2020, showing a significant increase in AF ablation procedures among the elderly, especially those aged 75 and older.
  • Results indicate a decrease in major adverse cardiovascular events (MACE) over time and that age is not a consistent predictor of AF-related complications or the need for further treatment.
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Overcrowded alkenes have received considerable attention as versatile structural motifs in a range of optical switches and light-driven unidirectional motors. In contrast, their actuation by electrochemical stimuli remains underexplored, even though this alternative energy input may be preferred in various applications and enables additional control over molecular switching states and properties. While symmetric bistricyclic overcrowded enes (BAEs) containing two identical halves based on either thioxanthene (TX) or acridine (Acr) motifs are known to be reversible conformational redox switches, their redox potentials are generally too high or low, respectively, thereby preventing wider applications.

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The ability to continually monitor target ion species in real-time is a highly sought-after endeavour in the field of host-guest chemistry, given its direct pertinence to medical and environmental applications. Developing methodologies which support sensitive and continuous ion sensing in aqueous media, however, remains a challenge. Herein, we present a versatile and facile, proof-of-concept electrochemical sensing methodology based on non-faradaic capacitance, which can be operated continuously with high temporal resolution (≈1.

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