We demonstrate a technique that uses high-order harmonic generation in molecules to probe nuclear dynamics and structural rearrangement on a subfemtosecond time scale. The chirped nature of the electron wavepacket produced by laser ionization in a strong field gives rise to a similar chirp in the photons emitted upon electron-ion recombination. Use of this chirp in the emitted light allows information about nuclear dynamics to be gained with 100-attosecond temporal resolution, from excitation by an 8-femtosecond pulse, in a single laser shot. Measurements on molecular hydrogen and deuterium agreed well with calculations of ultrafast nuclear dynamics in the H2+ molecule, confirming the validity of the method. We then measured harmonic spectra from CH4 and CD4 to demonstrate a few-femtosecond time scale for the onset of proton rearrangement in methane upon ionization

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In keeping with the focus of this special section, we concentrate initially on some of the problems of autonomist Marxist concepts such as 'immaterial labour', 'affective labour' and 'precarity' for understanding work in the cultural industries. We then briefly review some relevant media theory (John Thompson's notion of mediated quasi-interaction) and some key recent sociological research on cultural labour (especially work by Andrew Ross and Laura Grindstaff, the latter drawing on Hochschild's concept of emotional labour), which we believe may be more useful than autonomist concepts in developing empirically informed critique. The main body of the article then consists of an ethnographic account of working on one particular television programme, an account that aims to build on these theoretical debates. We analyse how the power to provide exposure or not to individuals in the talent show genre in contemporary television (a feature that derives from the symbolic power of producers to make texts that are then circulated to massive numbers of people) and disputes between commissioners and independent producers about how best to go about doing so (an organizational issue) are registered in the form of stress, anxiety and sometimes poor working relations among project teams of young television researchers (a matter of working conditions and experiences). We especially focus on how additional pressures are borne by these workers because of the requirements to undertake emotional labour, involving the handling of strong emotions on the part of talent show contributors, and to maintain good working relations in short-term project work, requirements generated by the need to ensure future employment. Ultimately, then, we support the view that creative work is 'precarious' -but we go beyond the generalizations involved in concepts such as immaterial labour and affective labour to show the specific ways in which precariousness is registered and negotiated in the lives of young workers in one industry.

This chapter addresses work ‘segregation’ by sex in the cultural industries. We outline some of the main forms this takes, according to our observations: the high presence of women in marketing and public relations roles; the high numbers of women in production co-ordination and similar roles; the domination of men of more prestigious creative roles; and the domination by men of technical jobs. We then turn to explanation: what gender dynamics drive such patterns of work segregation according to sex? Drawing on interviews, we claim that the following stereotypes or prevailing discourses, concerning the distinctive attributes of women and men, may influence such segregation: that women are more caring, supportive and nurturing; that women are better communicators; that women are ‘better organized’; and that men are more creative because they are less bound by rules.

Abstract:We report a new dynamic two-centre interference effect in High-HarmonicGeneration from H 2 , in which the attosecond nuclear motion of H 2 + initiated at ionisation causes interference to be observed at lower harmonic orders than would be the case for static nuclei. To enable this measurement we utilise a recently developed technique for probing the attosecond nuclear dynamics of small molecules. The experimental results are reproduced by a theoretical analysis based upon the strong field approximation which incorporates the temporally dependent two-centre interference term.High-harmonic generation (HHG) has proven to be a rich area of study over the last decade, finding application in a number of fields of laser science, such as coherent X-ray production [1,2] , attosecond pulse generation [3][4][5], and time resolved probing of nuclear dynamics [6,7]. HHG has also led to important advances towards the goal of structural imaging of small molecules [8][9][10][11][12][13][14][15], the harmonic emission depending strongly on the nature of the molecular orbital involved. This is seen most clearly within the Strong Field Approximation (SFA), in which the amplitude for HHG is determined by the Fourier transform of the bound state wavefunction.The wavefunctions relevant to HHG are those describing the propagated continuum electron ( c ψ ), and the bound electronic state from which the electron was ionised ( g ψ ). Recollision of the electron wavepacket with its parent ion results in a high local electron density (described by