To assess the use of a novel magnetic polymer implant in reversing airway collapse and identify potential anatomical targets for airway implant surgery in an in vivo porcine model.
Target sites of ...airway collapse were genioglossus muscle, hyoid bone, and middle constrictor muscle. Magnetic polymer implants were sutured to these sites, and external magnetic forces, through magnets with pull forces rated at 102 kg and 294 kg, were applied at the skin. The resultant airway movement was assessed via nasendoscopy. Pharyngeal plexus branches to the middle constrictor muscle were stimulated at 0.5 mA, 1.0 mA, and 2.0 mA and airway movement assessed via nasendoscopy.
At the genioglossus muscles, large magnetic forces were required to produce airway movement. At the hyoid bone, anterior movement of the airway was noted when using a 294 kg rated magnet. At the middle constrictor muscle, an anterolateral (or rotatory) pattern of airway movement was noted when using the same magnet. Stimulation of pharyngeal plexus branches to the middle constrictor revealed contraction and increasing rigidity of the lateral walls of the airway as stimulation amplitude increased. The resultant effect was prevention of collapse as opposed to typical airway dilation, a previously unidentified pattern of airway movement.
Surgically implanted smart polymers are an emerging technology showing promise in the treatment of airway collapse in obstructive sleep apnea. Future research should investigate their biomechanical role as an adjunct to treatment of airway collapse through nerve stimulation.
Cases are used as teaching tools at all levels—from primary to professional schools—and within all branches of knowledge. Cases put the content material into a context to make the information “come ...alive” for students. In PCOM's curriculum, cases have been used both in individual disciplines and in integrated courses. Over the past 10 years, the use of cases at PCOM has evolved to the present which represents the “classroom of the future.” In courses with a single discipline, cases were presented either as paper cases or video scenarios. Students had problems or questions to work through in small groups and subsequently discuss in larger groups from 40–260. When elective courses were offered, we developed cases that shared content from multiple disciplines. These cases were so well‐received by a self‐selected group of medical students that the course was offered to all 2nd year students; objectives were Board preparation and transition to the clinical. Innovations included team‐teaching by clinicians and basic scientists, touch‐pads to survey larger groups, non‐linear PowerPoint presentations, ExamMaster® to study pertinent board‐type questions, and introduction of mandatory on‐line responses, with optional class attendance. Finally, the case concepts have evolved to place them into appropriate required systems courses. In these contexts, all aspects are offered on‐line: the case, a set of Board‐type questions, review and explanation, and a quiz which counts toward the final course grade.
This paper presents new insights into the growth of small and medium-sized enterprises (SMEs) engaged in vertical inter-firm relationships. It adopts a processual and resource-based perspective and ...focuses on the experiences of fresh produce businesses which have achieved high rates of growth while supplying the UK's large multiple food retailers. The context in which these suppliers operate is shown to be a complex and dynamic supply chain, characterised by increasing structural concentration and close vertical linkages. The primary research investigates how certain SMEs have prospered in an apparently "hostile" environment. It includes a programme of matched-depth interviews, conducted across the retailer-supplier dyad. Content analysis of transcripts reveals six factors which appear to be strongly associated with the formation of "successful" relationships. In subsequent interactions, securing "developmental" supplier status appears to open the way to a self-reinforcing cycle of Penrosian learning and reinvestment. This cycle contributes to growth in the supplier firm. The authors argue that, with certain crucial caveats, growth-oriented SMEs can develop mutually beneficial relationships with much larger "customer" firms. The paper concludes by drawing out wider policy implications and indicating how this contextualised approach might be used in other contexts.
This paper presents new insights into the growth of small and mediumsized enterprises SMEs engaged in vertical interfirm relationships. It adopts a processual and resourcebased perspective and ...focuses on the experiences of fresh produce businesses which have achieved high rates of growth while supplying the UKs large multiple food retailers. The context in which these suppliers operate is shown to be a complex and dynamic supply chain, characterised by increasing structural concentration and close vertical linkages. The primary research investigates how certain SMEs have prospered in an apparently hostile environment. It includes a programme of matcheddepth interviews, conducted across the retailersupplier dyad. Content analysis of transcripts reveals six factors which appear to be strongly associated with the formation of successful relationships. In subsequent interactions, securing developmental supplier status appears to open the way to a selfreinforcing cycle of Penrosian learning and reinvestment. This cycle contributes to growth in the supplier firm. The authors argue that, with certain crucial caveats, growthoriented SMEs can develop mutually beneficial relationships with much larger customer firms. The paper concludes by drawing out wider policy implications and indicating how this contextualised approach might be used in other contexts.
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