4 research outputs found
The concept of remembrance in Walter Benjamin
This thesis argues that the role played by the concept of remembrance (Eingedenken)
in Walter Benjamin's 'theory of the knowledge of history' and in his engagement with
Enlightenment universal history, is a crucial one. The implications of Benjamin's
contention that history's 'original vocation' is 'remembrance' have hitherto gone
largely unnoticed. The following thesis explores the meaning of the concept of
remembrance and assesses the significance of this proposed link between history and
memory, looking at both the mnemonic aspect of history and the historical facets of
memory. It argues that by mobilising the simultaneously destructive and constructive
capacities of remembrance, Benjamin sought to develop a critical historiography
which would enable a radical encounter with a previously suppressed past. In so doing
he takes up a stance (explicit and implicit) towards existing philosophical conceptions
of history, in particular the idea of universal history found in German Idealism.
Benjamin reveals an intention to retain the epistemological aspirations of universal
history whilst ridding that approach of its apologetic moment. He criticises existing
conceptions of history on the basis that each assumes homogeneous time to be the
framework in which historical events occur. Insight into the distinctive temporality of
remembrance proves to be the touchstone for this critique, and provides a paradigm
for a very different conception of time. The thesis goes on to determine what is valid
and what is problematic both in this concept of remembrance and in the theory of
historical knowledge which it informs, by subjecting both to the most cogent
criticisms which can be levelled at them. What emerges is not only the importance of
this concept for an understanding of Benjamin's philosophy but the pertinence of this
concept for any philosophical account of memory
Examination of the Effects of Heterogeneous Organization of RyR Clusters, Myofibrils and Mitochondria on Ca2+ Release Patterns in Cardiomyocytes
Spatio-temporal dynamics of intracellular calcium, [Ca2+]i, regulate the contractile function of cardiac muscle cells. Measuring [Ca2+]i flux is central to the study of mechanisms that underlie both normal cardiac function and calcium-dependent etiologies in heart disease. However, current imaging techniques are limited in the spatial resolution to which changes in [Ca2+]i can be detected. Using spatial point process statistics techniques we developed a novel method to simulate the spatial distribution of RyR clusters, which act as the major mediators of contractile Ca2+ release, upon a physiologically-realistic cellular landscape composed of tightly-packed mitochondria and myofibrils.We applied this method to computationally combine confocal-scale (~ 200 nm) data of RyR clusters with 3D electron microscopy data (~ 30 nm) of myofibrils and mitochondria, both collected from adult rat left ventricular myocytes. Using this hybrid-scale spatial model, we simulated reaction-diffusion of [Ca2+]i during the rising phase of the transient (first 30 ms after initiation). At 30 ms, the average peak of the simulated [Ca2+]i transient and of the simulated fluorescence intensity signal, F/F0, reached values similar to that found in the literature ([Ca2+]i 1 μM; F/F0 5.5). However, our model predicted the variation in [Ca2+]i to be between 0.3 and 12.7 μM (~3 to 100 fold from resting value of 0.1 μM) and the corresponding F/F0 signal ranging from 3 to 9.5. We demonstrate in this study that: (i) heterogeneities in the [Ca2+]i transient are due not only to heterogeneous distribution and clustering of mitochondria; (ii) but also to heterogeneous local densities of RyR clusters. Further, we show that: (iii) these structureinduced heterogeneities in [Ca2+]i can appear in line scan data. Finally, using our unique method for generating RyR cluster distributions, we demonstrate the robustness in the [Ca2+]i transient to differences in RyR cluster distributions measured between rat and human cardiomyocytes