A Behavioural Foundation for Natural Computing and a Programmability Test

What does it mean to claim that a physical or natural system computes? One answer, endorsed here, is that computing is about programming a system to behave in different ways. This paper offers an account of what it means for a physical system to compute based on this notion. It proposes a behavioural characterisation of computing in terms of a measure of programmability, which reflects a system's ability to react to external stimuli. The proposed measure of programmability is useful for classifying computers in terms of the apparent algorithmic complexity of their evolution in time. I make some specific proposals in this connection and discuss this approach in the context of other behavioural approaches, notably Turing's test of machine intelligence. I also anticipate possible objections and consider the applicability of these proposals to the task of relating abstract computation to nature-like computation.Comment: 37 pages, 4 figures. Based on an invited Talk at the Symposium on Natural/Unconventional Computing and its Philosophical Significance, Alan Turing World Congress 2012, Birmingham, UK. http://link.springer.com/article/10.1007/s13347-012-0095-2 Ref. glitch fixed in 2nd. version; Philosophy & Technology (special issue on History and Philosophy of Computing), Springer, 201

Disablism in the lives of people living with a chronic illness in England and Portugal

This paper is based on research about the daily lives of people living with chronic illnesses in England and Portugal. Through the first-person narratives of participants, I argue that the lives of people living with debilitating chronic illnesses are affected by disablism, discrimination and exclusion. These aspects affect them in several important realms of life such as lack of or poor social support, difficulties in obtaining reasonable adjustments or the inability to obtain any kind of state support at all. These aspects are also widespread and compound and greatly influence their lives, beyond or in addition to the physical experience of the illness itself. I conclude that it is fundamental to change these structural and policy aspects so that people can have access to what I have termed a paradigm of sustained wellbeing, despite the illness

Protective effect of a PAR2-activating peptide on histamine-induced bronchoconstriction in guinea-pig

1. Protease activated receptor-2 (PAR2) is a seven transmembrane domain G protein coupled receptor proteolytically activated. PAR2, together with other PARs, can be also activated by peptides mimicking the sequence of the receptor tethered ligand. We have evaluated the effect of systemic administration of a peptide activating PAR2 (PAR2-AP, SLIGRL) on histamine-induced increase in lung resistances in the guinea-pig. 2. Intravenous administration of PAR2-AP (1 mg kg(−1)) significantly inhibited histamine-induced increase in lung resistance in a time-dependent fashion that was not abolished by indomethacin or vagotomy. 3. Bronchoprotective effect of PAR2-AP was not reversed by the cyclo-oxygenase inhibitor, indomethacin, the nitric oxide synthetase inhibitor, L-NAME, nor by the non-selective beta-antagonist, propranolol. 4. Indomethacin augmented the bronchoconstriction to histamine which was inhibited by PAR2-AP. Furthermore, in vagotomized animals, the bronchial hyper-responsiveness to histamine was significantly reduced, and in these circumstances, PAR2-AP still retained the capacity to provide bronchoprotection against histamine. 5. PAR2-AP also produced a modest reduction in histamine-induced protein leakage in trachea and upper bronchi. 6. Our results indicated that PAR2 might have a bronchoprotective role in the guinea-pig in vivo independent of prostaglandin or nitric oxide release