L C Ming | PubMed Health

PubMed2005

Identification of the diamond-like B-C phase by confocal Raman spectroscopy.

The new diamond-like B-C phase was obtained from the graphite-like BC phase in a laser-heated diamond anvil cell at high temperature 2230+/-140 K and high pressure 45 GPa. Raman spectra of the new phase measured at ambient conditions revealed a peak at 1315 cm(-1), which was attributed to longitudinal-optical (LO) mode. The X-Y Raman mapping was used to investigate spatial distribution of the diamond-like phases and was shown to be a powerful tool in studying the sp(2)-to-sp(3) phase transformations occurring in the diamond cell under high temperature and high pressure.

Diamond↗

PubMed2001

[Advanced sleep phase syndrome].

The Advanced Sleep Phase Syndrome (ASPS) is a sleep disorder characterized by an early sleep onset and early awakening without any disturbance of the sleep structure. The management of this disease requires clinical and laboratory investigations in an attempt to confirm the phase advance of body core temperature and melatonin rhythm. The use of light therapy, possibly associated with chronotherapy or melatonin intake has been proposed. The evolution is variable. Seven subjects, aged 15 to 72 were diagnosed in our sleep disorders unit by mean of sleep log, actigraphy, sleep and temperature recording. The sleep onset and sleep offset times were approximately the same according to sleep log, actigraphy and night polysomnography. The nadir of body core temperature was at 01:38 +/- 01:03. Two familial cases were identified of which 1 was investigated in constant routine condition with hourly blood sampling. An advanced phase of melatonin and cortisol was evidenced. The disease temporarily improved in 3 cases with light therapy and in one case with the association of light therapy and chronotherapy. These data show the difficulties of the management and the treatment of this rarely diagnosed disease.

Adolescent↗