Cardiovascular activity was measured at resting baseline and in response to a car racing game, undertaken in competition or in cooperation with an experimenter, or individually. Competitiveness and win and goal orientations were assessed by questionnaire. Competition provoked increases in blood pressure and heart rate, and a significant shortening of the preejection period, an index of enhanced beta-adrenergic influences on the heart. The cooperation task was largely without effect, and although the solo task affected cardiovascular activity, it did so to a lesser extent and much less consistently than did the competition task. The three task conditions, then, were largely distinguishable by their capacity to activate beta-adrenergic processes. Participants high in competitiveness and desire to win showed higher blood pressure reactions and greater shortening of the preejection period to competition than those low in these characteristics.

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Despite its common use as a laboratory model, little is known about the in-vivo forces and moments applied to the bovine caudal intervertebral disc. This is particularly critical, as intervertebral disc tissue is known to remodel in response to repeated loading. We hypothesized that the magnitude of loading from muscle contraction during a typical lateral bending motion varies between caudal levels and is accompanied by variations in tissue microstructure. This hypothesis was tested by estimating level-wise forces and bending moments using two independent approaches: a dynamic analytical model of the motion and analysis of muscle cross sections obtained via computed tomography. Microstructure was assessed by measuring collagen fiber crimp period in the annulus fibrosus, and composition was assessed via quantitative histology. Both the analytical model and muscle cross-sections estimated peak bending moments of over 3Nm and peak compressive force of over 125N at the c1c2 level, decreasing distally. There was a significant downward trend from proximal to distal in outer annulus fibrosus collagen crimp period only in the anterior and posterior regions, suggesting remodeling in response to the highest lateral bending moments. There were no observed trends in composition. Our results suggest that while the proximal discs in the bovine tail are subjected to forces and moments from muscle contraction which are comparable (relative to disc size) to those acting on human lumbar discs, the distal discs are not. The resulting pattern of microstructural microstructure suggests that level-wise differences should be considered when using bovine discs as a research model.

Individuals with a laryngectomy face a host of challenges ranging from restricted vocal communication to significant lifestyle modifications associated with breathing through a stoma. Although there are significant mental and physical health benefits achieved by returning to recreational pursuits that were enjoyed pre-surgery, there can be significant obstacles in doing so. One particular challenge arises during participation in water activities (e.g, fishing, boating, etc.) where accidental submersion poses a significant risk of drowning. This manuscript describes a proof-of-concept device that protects the airway from accidental incursion of water into the airway during unanticipated submersion in water, thereby allowing laryngectomees to return to participation in water activities. The device is designed to be worn comfortably for long periods of time, while not interfering with the common methods of replacement speech that are utilized post-laryngectomy.