Diurnal variation of steroid hormones and their reference intervals using mass spectrometric analysis

Objective: Accurate measurement of steroid hormones remains challenging. Mass spectrometry affords a reliable means for quantitating steroid profiles accurately. Our objective was to establish and define (1) the extent of diurnal fluctuations in steroid concentrations that potentially necessitate strict adherence to time of sample acquisition and (2) time-dependent steroid reference intervals. Design: Nine steroid markers were examined in couplets in males and females. Methods: Using isotope dilution high-performance liquid chromatography–tandem mass spectrometric (LC–MS/MS) analysis, we developed a multi-steroid profile requiring only a minimal volume of serum (0.1 mL). Couplet (AM and PM) measurements of steroid hormones for 120 healthy females (F) and 62 healthy males (M) were obtained. Patients were recruited from several participating centers. Results: The following diurnal values were noted to be significantly different in both females and males: cortisone, cortisol, corticosterone, 11 deoxycortisol (11 DOC), androstenedione, 17a-hydroxyprogesterone (17 OHP) and dehydroepiandrosterone (DHEA). Testosterone was only found to have significant diurnal variance in males. Progesterone showed no significant difference in AM and PM values for either groups and thus may provide an internal control. Conclusions: When diagnosing endocrine disorders, it is imperative to acknowledge the 24-h diurnal variation of the biochemical steroid markers. We highlight the importance of standardization of collection times and appropriate implementation of reference intervals. Precis: We identify diurnal fluctuations in steroid concentrations with time of day and emphasize the importance of adhering to firm time of sample acquisition

Structured film-viewing preferences and practices : a quantitative analysis of hierarchies in screen and content selection amongst young people in Flanders

Aleit Veenstra, Philippe Meers and Daniel Biltereyst address a specific segment of a typical small-market audience—Flemish youth film viewers. Their study “Structured Film Viewing Preferences and Practices: A Quantitative Analysis of Hierarchies in Screen and Content Selection among Young People in Flanders” deals with one of the symptomatic problems of the era of convergent audiences, the multiplication of screens used for domestic consumption of audiovisual content. Building an intriguing empirical design, Veenstra and her colleagues aim to identify patterns of screen selection and their relation to the perceived value of Hollywood, European and domestic Flemish films. Their conclusion is that there are well-articulated hierarchies applied by the audience members in the selection of both film titles and reception screens and that, to put it simply, in the case of screens, size matters

Copy rights: The politics of copying and creativity

This article analyses the politics of copyright and copying. Copyright is an increasingly important driver of the modern economy, but this does not exhaust its significance. It matters, we argue, not just for the distribution of rewards and resources in the creative industries, but as a site within which established political concerns – collective and individual interests and identities - are articulated and negotiated, and within which notions of ‘originality’, ‘creativity’ and ‘copying’ are politically constituted. Set against the background of the increasing economic value attributed to the creative industries, the impact of digitalization on them, and the European Union’s Digital Single Market strategy, the article reveals how copyright policy, and the underlying assumptions about ‘copying’ and ‘creativity’, express (often unexamined) political values and ideologies. Drawing on a close reading of policy statements, official reports, court cases, and interviews with stakeholders, we explore the multiple political aspects of copyright, showing how copyright policy operates to privilege particular interests and practices, and to acknowledge only specific forms of creative endeavour