Epidemiological studies link short sleep and circadian disruption with risk of metabolic syndrome and diabetes. We tested the hypotheses that prolonged sleep restriction with concurrent circadian disruption, as can occur with shift work, impairs glucose regulation and metabolism. Healthy adults spent >5 weeks in controlled laboratory conditions including: sleep extension (baseline), 3-week sleep restriction (5.6 h sleep/24 h) combined with circadian disruption (recurring 28-h ‘days’), and 9-day recovery sleep with circadian re-entrainment. Prolonged sleep restriction with concurrent circadian disruption significantly decreased resting metabolic rate, and increased postprandial plasma via inadequate pancreatic beta cell responsivity; these normalized with 9 days of recovery sleep and stable circadian reentrainment. Thus, in humans, prolonged sleep restriction with concurrent circadian disruption alters metabolism and could increase risk of obesity and diabetes.

Our preliminary finding of a global reduction in GABA in non-medicated individuals with PI is the first demonstration of a neurochemical difference in the brains of those with PI compared to normal sleeping controls. 1H-MRS is a valuable tool to assess GABA in vivo, and may provide a means to shed further light on the neurobiology of insomnia.

Academy of Architecture for Health, Facilities Guidelines Institute, and The Center for Health Design.

Winkelman JW; Plante DT; Schoerning L; Benson K; Buxton OM; O'Connor SP; Jensen JE; Renshaw PF; Gonenc A. Increased rostral anterior cingulate cortex volume in chronic primary insomnia. 2013;36(7):991-998.

Oriented absorption and fluorescence spectra, refractive indices, thermal expansion, and thermal conductivities are reported for the anisotropic laser material ytterbium-doped potassium gadolinium tungstate, Yb3+:KGd(WO4)2. Measurements of negative values for dn/dT lead to the report of several useful athermal orientations for laser propagation.

No abstract

No abstract

No abstract