65 research outputs found
Regulation of Lipogenesis by Glucocorticoids and Insulin in Human Adipose Tissue
Patients with glucocorticoid (GC) excess, Cushing's syndrome, develop a classic phenotype characterized by central obesity and insulin resistance. GCs are known to increase the release of fatty acids from adipose, by stimulating lipolysis, however, the impact of GCs on the processes that regulate lipid accumulation has not been explored. Intracellular levels of active GC are dependent upon the activity of 11β-Hydroxysteroid dehydrogenase type 1 (11β-HSD1) and we have hypothesized that 11β-HSD1 activity can regulate lipid homeostasis in human adipose tissue (Chub-S7 cell line and primary cultures of human subcutaneous (sc) and omental (om) adipocytes. Across adipocyte differentiation, lipogenesis increased whilst β-oxidation decreased. GC treatment decreased lipogenesis but did not alter rates of β-oxidation in Chub-S7 cells, whilst insulin increased lipogenesis in all adipocyte cell models. Low dose Dexamethasone pre-treatment (5 nM) of Chub-S7 cells augmented the ability of insulin to stimulate lipogenesis and there was no evidence of adipose tissue insulin resistance in primary sc cells. Both cortisol and cortisone decreased lipogenesis; selective 11β-HSD1 inhibition completely abolished cortisone-mediated repression of lipogenesis. GCs have potent actions upon lipid homeostasis and these effects are dependent upon interactions with insulin. These in vitro data suggest that manipulation of GC availability through selective 11β-HSD1 inhibition modifies lipid homeostasis in human adipocytes
Appropriate control methods for mobile virtual exhibitions
It is becoming popular to render art exhibitions in Virtual Reality (VR). Many of these are used to deliver at-home experiences on peoples’ own mobile devices, however, control options on mobile VR systems are necessarily less flexible than those of situated VR fixtures. In this paper, we present a study that explores aspects of control in such VR exhibitions - specifically comparing ‘on rails’ movement with ‘free’ movement.We also expand the concept of museum audio guides to better suit the VR medium, exploring the possibility of embodied characterguides. We compare these controllable guides with a more traditional audio-guide. The study uses interviews to explore users’ experience qualitatively, as well as questionnaires addressing both user experience and simulator sickness. The results suggest that users generally prefer to have control over both their movement and the guide, however, if relinquishing movement control, they prefer the uncontrolled guide. The paper presents three key findings: (1) users prefer to be able to directly control their movement; (2) this does not make a notable difference to simulator sickness; (3) embodied guides are potentially a good way to deliver additional information in VR exhibition settings
Characterizing first and third person viewpoints and their alternation for embodied interaction in virtual reality
Empirical research on the bodily self has shown that the body representation is malleable, and prone to manipulation when conflicting sensory stimuli are presented. Using Virtual Reality (VR) we assessed the effects of manipulating multisensory feedback (full body control and visuo-tactile congruence) and visual perspective (first and third person perspective) on the sense of embodying a virtual body that was exposed to a virtual threat. We also investigated how subjects behave when the possibility of alternating between first and third person perspective at will was presented. Our results support that illusory ownership of a virtual body can be achieved in both first and third person perspectives under congruent visuo-motor-tactile condition. However, subjective body ownership and reaction to threat were generally stronger for first person perspective and alternating condition than for third person perspective. This suggests that the possibility of alternating perspective is compatible with a strong sense of embodiment, which is meaningful for the design of new embodied VR experiences
Interaction for Immersive Analytics
International audienceIn this chapter, we briefly review the development of natural user interfaces and discuss their role in providing human-computer interaction that is immersive in various ways. Then we examine some opportunities for how these technologies might be used to better support data analysis tasks. Specifically, we review and suggest some interaction design guidelines for immersive analytics. We also review some hardware setups for data visualization that are already archetypal. Finally, we look at some emerging system designs that suggest future directions
- …