Only a few previous studies have investigated paraspinal musculature (i.e., multifidus (MF), psoas major (PSM), erector spinae (ES)) in longitudinal, population-based settings. This study aimed to evaluate changes in the cross-sectional area (CSA) of the paraspinal muscles between the ages of 20 and 30 years. The study population consisted of a sub-cohort from the Northern Finland Birth Cohort 1986 (n = 298; 156 men, 142 women). Baseline magnetic resonance imaging was performed at a mean age of 21.3 years and follow-up imaging at 30.6 years. The CSA measurements were performed by tracing the paraspinal muscle outlines individually (MF, ES, PM) and all combined (total muscle area (TMA)) at the L4 cranial endplate level. The longitudinal data analysis was performed using generalized estimating equations modelling. The CSA of MF and ES increased during the follow-up among both sexes (men: MF + 5.7%, p < 0.001; ES + 2.7%, p = 0.001; and women: MF + 10.5%, p < 0.001; ES 9.2%, p = 0.001). The CSA of PM decreased among men (PM −4.0%, p < 0.001) but not among women (PM + 0.5%, p = 0.553). TMA increased significantly only among women (men: +0.5%, p = 0.425; women: +6.5%, p < 0.001). The increases in ES and TMA were more distinct among women than men (p < 0.001). Our study demonstrated clear age- and sex-related changes in paraspinal muscle size in early adulthood.

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A short essay on what is the role of art in society, what is the impact of art on society and what the terms avantgarde and critical art might mean today.

This exposition concerns the relationship between art and research. It focuses on the questions: How can we define knowledge and research in the context of artistic research? What is artistic research? What is its goal? How is it different from other traditions of combining art and research? How should the university system react to and make use of artistic research? What is artistic knowledge and how is it used? How can we justify art as a special, flexible form of research? In what sense is art a philosophical and political practice – not just a way of communicating philosophical and political ideas and reasoning, but an especially powerful and holistic form of philosophy and politics? The first half of the exposition analyses and develops a line of reasoning about these concepts and categories. It also includes an attempt to justify art as philosophy/politics. The second half of the exposition lists the five main traditions of combining art and research and the pros and cons of each of them. The latter half of the exposition, in particular, uses images, videos, and music as examples of these traditions, and in some way as proof of the philosophical/political claim of the exposition. The whole exposition is built concretely from the viewpoint of a practicing artist, looking for insights and ways that could help him and other artists in their artistic work.