Static postural stability and neuropsychological performance after awakening from REM and NREM sleep in patients with chronic insomnia: a randomized, crossover, overnight polysomnography study.

STUDY OBJECTIVES: Chronic insomnia disorder (CID) is a common sleep disorder, with a prevalence ranging from 6%-10% worldwide. Individuals with CID experience more fragmented sleep than healthy control patients do. They awaken frequently during the night and have a higher risk of injury from falling. Awakening from different sleep stages may have different effects on postural stability and waking performance. However, limited research has been conducted on this topic. METHODS: This prospective randomized crossover study was conducted between January 2015 and January 2017. We included 20 adults aged 20-65 years who fulfilled the diagnosis criteria for CID. Participants underwent 2 overnight polysomnography studies with an interval of at least 7 days. They were awakened during either rapid eye movement (REM) sleep or stage N1/N2 sleep alternatively. We compared measurements of static postural stability, vigilance scores, and neuropsychological tests between REM sleep and stage N1/N2 sleep awakening. RESULTS: Polysomnography parameters between the 2 nights were comparable. Participants who were awakened from REM sleep had worse static postural stability than those with stage N1/N2 sleep awakening. Compared with stage N1/N2 sleep awakening, larger mean sway areas of center of pressure (P = .0413) and longer center-of-pressure mean distances (P = .0139) were found in REM sleep awakening. There were no statistically significant differences in vigilance scores or neuropsychological tests between the 2 nights. CONCLUSIONS: REM sleep awakening was associated with worse static postural stability than was stage N1/N2 sleep awakening. No statistically significant differences were found in waking performance in alertness or in neuropsychological tests between stage N1/N2 and REM sleep awakening. CITATION: Yeh W-C, Chuang Y-C, Yen C-W, et al. Static postural stability and neuropsychological performance after awakening from REM and NREM sleep in patients with chronic insomnia: a randomized, crossover, overnight polysomnography study. J Clin Sleep Med. 2022;18(8):1983-1992.

Influence of ion assistance on LaF3 films deposited by molybdenum boat evaporation.

LaF3 thin films at 193 nm were deposited by the molybdenum boat evaporation with ion-assisted deposition (IAD). Various optical characteristics, stress, and microstructures that formed under different ion-beam voltages of IAD deposition were investigated. The relation between these properties is also discussed. LaF3 films deposited with IAD exhibited small rough surfaces and large optical loss at 193 nm. The largest value of optical loss for films at 193 nm, which were prepared at an ion-beam voltage of 400 V, was 1.55% and the extinction coefficient was smaller than 0.0015. Microstructures and crystalline structures of films were influenced and changed by the ion-assisted deposition process. Tensile stress value of films increased as the ion-beam voltage rose. Refractive index, related to the packing density and microstructures, also increased as the ion-beam voltage rose.

Discharge and photo-luminance properties of a parallel plates electron emission lighting device.

The gas discharge and photo-luminance properties of a planar lighting source featuring highly uniform light emission and mercury-free design were studied. The current density-voltage characteristics and the associated gas discharge of the devices operating with the values of the ratio of electric field to gas pressure (E/p) between 4.3 kV/Torr-cm and 35.7 kV/Torr-cm indicate that the width of the cathode fall extends over the entire gap between the two electrodes and the device is mostly in the obstructed discharge regime. The optical emission analysis confirmed the electron collision-induced gas emissions and strong effect of gas pressure on the phosphor emission when operated at constant current density, both are indicative of the primary roles played by the electron energy.

Developing new manufacturing methods for the improvement of AlF3 thin films.

In this research, the plasma etching mechanism which is applied to deposit AlF(3) thin films has been discussed in detail. Different ratios of O(2) gas were injected in the sputtering process and then the optical properties and microstructure of the thin films were examined. The best optical quality and smallest surface roughness was obtained when the AlF(3) thin films were coated with O(2):CF(4) (12 sccm:60 sccm) at 30 W sputtering power. To increase the deposition rate for industrial application, the sputtering power was increased to 200 W with the best ratio of O(2)/CF(4) gas. The results show that the deposition rate at 200W sputtering power was 7.43 times faster than that at 30 W sputtering power and the extinction coefficients deposited at 200 W are less than 6.8 x 10(-4) at the wavelength range from 190 nm to 700 nm. To compare the deposition with only CF(4) gas at 200 W sputtering power, the extinction coefficient of the thin films improve from 4.4 x 10(-3) to 6 x 10(-4) at the wavelength of 193 nm. In addition, the structure of the film deposited at 200W was amorphous-like with a surface roughness of 0.8 nm.

Fluoride antireflection coatings deposited at 193 nm.

Antireflection coatings for 193 nm composed of low-index (MgF(2) and AlF(3)) and high-index (LaF(3) and GdF(3)) materials are deposited by the resistive heating boat method at a substrate temperature of 300 degrees C. The optical characteristics (reflectance and optical loss), microstructure (morphology and surface roughness), stress, and laser-induced damage threshold (LIDT) of the coatings are investigated and discussed. The related reflection at 193 nm of the four kinds of antireflection coatings is smaller than 0.2% and the optical loss is less than 0.15%. Of the fluoride antireflection coatings, AlF(3)/GdF(3) had the lowest stress value. Antireflection coatings with AlF(3) as the low-index material had higher LIDT values than when MgF(2) was used.

Residual stress in obliquely deposited MgF2 thin films.

MgF(2) films with a columnar microstructure are obliquely deposited on glass substrates by resistive heating evaporation. The columnar angles of the films increases with the deposition angle. Anisotropic stress does not develop in the films with tilted columns. The residual stresses in the films depend on the deposition and columnar angles in a columnar microstructure.

Process for deposition of AlF3 thin films.

We fabricated aluminum fluoride (AlF(3)) thin films by pulsed DC magnetron sputtering with various CF(4) flow rates and sputtering powers. Our method is distinct from the conventional deposition process in that we used inexpensive Al (99.99% purity) as the target instead of an expensive fluoride compound. The optical properties and microstructure of the thin films were examined. The optical quality of AlF(3) thin films deposited at a 20 W sputtering power and injected 110 SCCM (SCCM denotes cubic centimeters per minute at standard temperature and pressure) CF(4) flow at room temperature showed improvement with an extinction coefficient of less than 7 x 10(-4) at 193 nm. The deposition of AlF(3) thin films at different substrate temperatures and annealed by UV light was also investigated.

AlF(3) thin films deposited by reactive magnetron sputtering with Al target.

Aluminum fluoride thin films have been deposited by magnetron sputtering of an aluminum target with CF(4) , and CF(4) mixed O(2) as the working gas onto a room temperature substrate. The quality of the coated AlF(3) film applied with 25W sputtering power using CF(4) mixed 5% O(2) was better than for films deposited using conventional methods. The extinction coefficient of AlF(3) was smaller than 6.0x10(-4) in the wavelength range of 190nm to 250nm. Single layer antireflection coatings on both sides of a fused silica substrate increased the transmittance from less than 91% for a bare substrate to higher than 96% in the wavelength range between 190nm to 250nm.

Microstructure of magnesium fluoride films deposited by boat evaporation at 193 nm.

Single layer magnesium fluoride (MgF2) was deposited on fused-silica substrates by a molybdenum boat evaporation process at 193 nm. The formation of various microstructures in relation to the different substrate temperatures and deposition rates were investigated. The relation between these microstructures (including cross-sectional morphology, surface roughness, and crystalline structures), the optical properties (including refractive index and optical loss) and stress, were all investigated. It was found that the laser-induced damage threshold (LIDT) would be affected by the microstructure, optical loss, and stress of the thin film. To obtain a larger LIDT value and better optical characteristics, MgF2 films should be deposited at a high substrate temperature (300 degrees C) and at a low deposition rate (0.05 nm s(-1)).

Microstructure-related properties at 193 nm of MgF2 and GdF3 films deposited by a resistive-heating boat.

MgF2 and GdF3 materials, used for a single-layer coating at 193 nm, are deposited by a resistive-heating boat at specific substrate temperatures. Optical characteristics (transmittance, refractive index, extinction coefficient, and optical loss) and microstructures (morphology and crystalline structure) are investigated and discussed. Furthermore, MgF2 is used as a low-index material, and GdF3 is used as a high-index material for multilayer coatings. Reflectance, stress, and the laser-induced damage threshold (LIDT) are studied. It is shown that MgF2 and GdF3 thin films, deposited on the substrate at a temperature of 300 degrees C, obtain good quality thin films with high transmittance and little optical loss at 193 nm. For multilayer coatings, the stress mainly comes from MgF2, and the absorption comes from GdF3. Among those coatings, the sixteen-layer design, sub/(1.4L 0.6H)8/air, shows the largest LIDT.

Characterization of AlF3 thin films at 193 nm by thermal evaporation.

Aluminum fluoride (AlF3) was deposited by a resistive heating boat. To obtain a low optical loss and high laser-induced damage threshold (LIDT) at 193 nm, the films were investigated under different substrate temperatures, deposition rates, and annealing after coating. The optical property (the transmittance, refractive index, extinction coefficient, and optical loss) at 193 nm, microstructure (the cross-sectional morphology, surface roughness, and crystalline structure), mechanical property (stress), and LIDT of AlF3 thin films have been studied. AlF3 thin films deposited at a high substrate temperature and low deposition rate showed a lower optical loss. The highest LIDT occurred at the substrate temperature of 150 degrees C. The LIDT of the films prepared at a deposition rate of 2 A/s was higher than that at other deposition rates. The annealing process did not influence the optical properties too much, but it did increase the LIDT and stress.

Influence of thermal annealing and ultraviolet light irradiation on LaF3 thin films at 193 nm.

Lanthanum fluoride (LaF3) thin films were prepared by resistive heating evaporation and electron-beam gun evaporation under the same deposition rate, deposition substrate temperature, and vacuum pressure. The coated LaF3 films were then treated by heat annealing and UV light irradiation. The optical properties, microstructures, stress, and laser-induced damage threshold (LIDT) at a wavelength of 193 nm were investigated. The surface roughness, optical loss, stress, and LIDT of the films were improved after the annealing. The films had better properties when irradiated by UV light as compared with heat annealing.