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Surgical tissue fusion devices ligate blood vessels using thermal energy and coaptation pressure, while the molecular mechanisms underlying tissue fusion remain unclear. This study characterizes the influence of apposition force during fusion on bond strength, tissue temperature, and seal morphology. Porcine splenic arteries were thermally fused at varying apposition forces (10-500 N). Maximum bond strengths were attained at 40 N of apposition force. Bonds formed between 10 and 50 N contained laminated medial layers; those formed above 50 N contained only adventitia. These findings suggest that commercial fusion devices operate at greater than optimal apposition forces, and that constituents of the tunica media may alter the adhesive mechanics of the fusion mechanism.

Renowned robotics engineer Rodney Brooks has built a career engineering behaviourally intelligent machines for scientific research, military-industrial applications, and domestic service. Drawing lessons from biology and ethology, Brooks designs embodied, responsive robots that he provocatively calls "artificial creatures." He has also been vocal about the broad implications his research carries for the future, making bold predictions about a technological society increasingly shaped by ecologies of animated machines. This dissertation examines a number of popular and academic texts in which Brooks discusses his artificial creatures, his design methodology, and his futurological speculations. Focusing on key moments from these texts, I discuss how he constructs a rhetorical and narrative framework through which he ascribes a sense of "life" to his robots in order to probe the distinction between the living and the nonliving and deliberately unsettle the bounds of the biological and the technological. As he highlights the lifelike qualities of his robots that raise them to the status of creatures, he simultaneously emphasizes the machine-like qualities of human beings, leading him to charge people with "overanthropomorphizing" themselves. I argue that these contrapuntal shifts call into question models of subjectivity derived from modern liberal humanism, insofar as they destabilize traditional relations between machines, animals, and human beings. In order to develop the broader theoretical implications of Brooks' work, I engage in comparative readings that place him in dialogue with philosophers such as Martin Heidegger, Bernard Stiegler, Jacques Derrida, and René Descartes, early cyberneticists Norbert Wiener and W. Grey Walter, and an offbeat video game called Chibi Robo! These readings afford opportunities to challenge modes of thinking and acting that assume human mastery over nature and technology, and subsequently to reevaluate our intimate connections to nonhuman beings that make human life livable in the first place. Ultimately, I endeavour to lay the groundwork for a bioethics that is responsive to redefinitions of life by technological means, one that eschews anthropocentrism in order to suggest a concern for different ways of living and belonging between humans and nonhumans, rather than for the lives of human beings alone.

Renowned robotics engineer Rodney Brooks has built a career engineering behaviourally intelligent machines for scientific research, military-industrial applications, and domestic service. Drawing lessons from biology and ethology, Brooks designs embodied, responsive robots that he provocatively calls "artificial creatures." He has also been vocal about the broad implications his research carries for the future, making bold predictions about a technological society increasingly shaped by ecologies of animated machines. This dissertation examines a number of popular and academic texts in which Brooks discusses his artificial creatures, his design methodology, and his futurological speculations. Focusing on key moments from these texts, I discuss how he constructs a rhetorical and narrative framework through which he ascribes a sense of "life" to his robots in order to probe the distinction between the living and the nonliving and deliberately unsettle the bounds of the biological and the technological. As he highlights the lifelike qualities of his robots that raise them to the status of creatures, he simultaneously emphasizes the machine-like qualities of human beings, leading him to charge people with "overanthropomorphizing" themselves. I argue that these contrapuntal shifts call into question models of subjectivity derived from modern liberal humanism, insofar as they destabilize traditional relations between machines, animals, and human beings. In order to develop the broader theoretical implications of Brooks' work, I engage in comparative readings that place him in dialogue with philosophers such as Martin Heidegger, Bernard Stiegler, Jacques Derrida, and René Descartes, early cyberneticists Norbert Wiener and W. Grey Walter, and an offbeat video game called Chibi Robo! These readings afford opportunities to challenge modes of thinking and acting that assume human mastery over nature and technology, and subsequently to reevaluate our intimate connections to nonhuman beings that make human life livable in the first place. Ultimately, I endeavour to lay the groundwork for a bioethics that is responsive to redefinitions of life by technological means, one that eschews anthropocentrism in order to suggest a concern for different ways of living and belonging between humans and nonhumans, rather than for the lives of human beings alone.

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