The biocompatibility of carbon nanotubes

Carbon nanotubes (CNT) are well-ordered, high aspect ratio allotropes of carbon. The two main variants, single-walled carbon nanotubes (SWCNT) and multi-walled carbon nanotubes (MWCNT) both possess a high tensile strength, are ultra-light weight, and have excellent chemical and thermal stability. They also possess semi- and metallic-conductive properties. This startling array of features has led to many proposed applications in the biomedical field, including biosensors, drug and vaccine delivery and the preparation of unique biomaterials such as reinforced and/or conductive polymer nanocomposites. Despite an explosion of research into potential devices and applications, it is only recently that information on toxicity and biocompatibility has become available. This review presents a summary of the performance of existing carbon biomaterials and gives an outline of the emerging field of nanotoxicology, before reviewing the available and often conflicting investigations into the cytotoxicity and biocompatibility of CNT. Finally, future areas of investigation and possible solutions to current problems are proposed. (c) 2005 Elsevier Ltd. All rights reserved.

Mapping civil society in former Yugoslavia

From the break up of the New Left into single issue groups at the end of the 1960s came a variety of groups representing the peace movement, environmental movement, student movement, women’s movement, and gay liberation movement. This explosion of new social movement activism has been heralded as the age of new radical politics. Many theorists and activists understand new social movements, as replacing the working class as an agent for progressive social change. Scholars and activists now alike debate the possibilities for revolutionary change in this era of multinational capitalism and new nationalisms. This paper examines some of the above claims in the context of the contemporary Serbian civil society. It explores the relationship between the civil society, activism, and narratives in Serbia. In particular, it examines the anti-Milosevic’ movement Otpor! (Resistance), and its discourse, practice and politics in public spaces, through an analysis of narratives of a set of roughly 20 interviews with Otpor! activists, aged 18-35. In the following discussion, then, I will focus on some of the particular dilemmas of contemporary Serbian popular movements - they are dilemmas to do with the growing complexity of media life in the Serbian spaces. I ground my debate on particular uses of the notion of civil society in the narratives of Otpor! activists, while I focus on the question of how do Otpor! activists relate to Leftist/radical politics and the idea of civil society.

Bandwidth requirements for shallow, high-resolution seismic reflection

The optimum bandwidth for shallow, high-resolution seismic reflection differs from that required for conventional petroleum reflection. An understanding of this issue is essential for correct choice of acquisition instrumentation. Numerical modelling of simple Bowen Basin coal structures illustrates that, for high-resolution imaging, it is important to accurately record all frequencies up to the limit imposed by earth scattering. On the contrary, the seismic image is much less dependent on frequencies at the lower end of the spectrum. These quantitative observations support the use of specialised high-frequency geophones for high-resolution seismic imaging. Synthetic seismic inversion trials demonstrate that, irrespective of the bandwidth of the seismic data, additional low-frequency impedance control is essential for accurate inversion. Inversion provides no compelling argument for the use of conventional petroleum geophones in the high-resolution arena.