Examining the Motivation and Perceived Benefits of Pickleball Participation in Older Adults.

Pickleball, a paddle sport that combines aspects of tennis, badminton, and table tennis, is one of the fastest growing sports in America. The sport is especially popular with older adults as it provides a means for both competition and exercise. Limited research is available on the motivation and perceived benefits of participants in this unique and growing community. A total of 3,012 participants completed a survey instrument that included items from the Sport Motivation Scale, the Task and Ego Orientation in Sport Questionnaire, and the Quality and Importance of Recreational Services. Participants reported being more task oriented than ego oriented, suggesting that pickleball may effectively satisfy the need for persons to be engaged in physical activities that allow for the ongoing development of personal mastery. This finding is supported by respondents noting that their primary motivation to participate in pickleball involved mastering difficult training techniques. However, participants cited competition as the top perceived benefit to their participation. This result supports two possible conclusions that motivation and benefit are different and potentially disconnected constructs or that the benefit of competition among this sample of older persons is understood through the lens of personal mastery, whereby the demonstration of that mastery is only possible through competition.

A short, organocatalytic formal synthesis of (-)-swainsonine and related alkaloids.

A short synthesis of hydroxyalkyl dihydropyrroles has been developed that involves the coupling of propargylamines with α-chloroaldehydes, followed by Lindlar reduction and a one-pot epoxide formation/opening sequence. The application of this process to the synthesis of unnatural iminosugars and a formal synthesis of (-)-swainsonine is described.

Bifunctional cis-abienol synthase from Abies balsamea discovered by transcriptome sequencing and its implications for diterpenoid fragrance production.

The labdanoid diterpene alcohol cis-abienol is a major component of the aromatic oleoresin of balsam fir (Abies balsamea) and serves as a valuable bioproduct material for the fragrance industry. Using high-throughput 454 transcriptome sequencing and metabolite profiling of balsam fir bark tissue, we identified candidate diterpene synthase sequences for full-length cDNA cloning and functional characterization. We discovered a bifunctional class I/II cis-abienol synthase (AbCAS), along with the paralogous levopimaradiene/abietadiene synthase and isopimaradiene synthase, all of which are members of the gymnosperm-specific TPS-d subfamily. The AbCAS-catalyzed formation of cis-abienol proceeds via cyclization and hydroxylation at carbon C-8 of a postulated carbocation intermediate in the class II active site, followed by cleavage of the diphosphate group and termination of the reaction sequence without further cyclization in the class I active site. This reaction mechanism is distinct from that of synthases of the isopimaradiene- or levopimaradiene/abietadiene synthase type, which employ deprotonation reactions in the class II active site and secondary cyclizations in the class I active site, leading to tricyclic diterpenes. Comparative homology modeling suggested the active site residues Asp-348, Leu-617, Phe-696, and Gly-723 as potentially important for the specificity of AbCAS. As a class I/II bifunctional enzyme, AbCAS is a promising target for metabolic engineering of cis-abienol production.

A concise and stereoselective synthesis of hydroxypyrrolidines: rapid synthesis of (+)-preussin.

A convergent and stereoselective synthesis of 2,5-disubstituted 3-hydroxypyrrolidines has been developed that involves reductive annulation of ß-iminochlorohydrins, which are readily available from ß-ketochlorohydrins, and provides rapid access to a variety of 2,5-syn-pyrrolidines. Application of this process to the concise (three-step) synthesis of the fungal metabolite (+)-preussin and analogues of this substance is reported.