A5069338863- Photonic and Optical Devices
- Advanced Fiber Optic Sensors
- Semiconductor Lasers and Optical Devices
- Photonic Crystal and Fiber Optics
- Sleep and related disorders
- Advanced Fiber Laser Technologies
- Solid State Laser Technologies
- Circadian rhythm and melatonin
- Sleep and Work-Related Fatigue
- Glass properties and applications
- Laser Design and Applications
- Spectroscopy and Laser Applications
- Optical Network Technologies
- Lymphoma Diagnosis and Treatment
- Sleep and Wakefulness Research
- Optical Coherence Tomography Applications
- Laser-Matter Interactions and Applications
- Photorefractive and Nonlinear Optics
- Spaceflight effects on biology
- Advanced Photonic Communication Systems
- Advanced Surface Polishing Techniques
- Impact of Light on Environment and Health
- Geophysics and Sensor Technology
- Acute Lymphoblastic Leukemia research
- Laser Material Processing Techniques
The University of Melbourne
2024
Monash University
2017-2024
Cooperative Research Centre for Mental Health
2021
Peter MacCallum Cancer Centre
1997
Statistics New Zealand
1996
AT&T (United States)
1981-1993
Nokia (United States)
1972-1992
University of California San Diego Medical Center
1992
St James's University Hospital
1992
Harrogate District Hospital
1992
Abstract Shift work is associated with impaired alertness and performance due to sleep loss circadian misalignment. This study examined between shift types (day, evening, night), during day night shifts in 52 intensive care workers. Sleep wake duration were evaluated using wrist actigraphs diaries. Subjective sleepiness (Karolinska Sleepiness Scale, KSS) Psychomotor Vigilance Test (PVT) shift, on the first subsequent (3 rd , 4 th or 5 ). Circadian phase was assessed urinary...
Fused SiO2 has been used as a new noncrystalline host for the fabrication of two types neodymium-doped room-temperature lasers, one which operates at 1.06-μm and other 1.08-μm wavelength. The lasers have geometry clad optical fibers, with active cores small 15-μm diameter by 1-cm length. They are end pumped 0.590 0.5145 μm pulsed dye laser an argon ion laser, respectively. Thresholds low 1–2 mW absorbed pump power in 40-μm-diam core obtained, eventual pumping high-radiance semiconductor...
Measurements have been made of the absorptivity 31 low-loss liquids by a new technique. The change refractive index sample caused temperature due to absorption light was measured with an interferometer. Absorptivity values as small 10−5 cm−1 measured. lowest were obtained for carbon tetrachloride, chloroform, and bromobenzene. heavy water is <5×10−5 cm−1, 1/60 that ordinary at same wavelength. 6328 Å.
Intense spontaneous Raman radiation has been obtained from C 6 H and 2 CI 4 by passing the focused beam an argon ion laser (4880 Å, 5 to 250 mW) through filled hollow fused quartz optical fibers having core diameters of ∼75 µm lengths 10 25 meters. Spectral intensifications factors ∼10 3 compared conventional sample techniques have with fiber optics method. spectra were recorded a Cary model 81 spectrophotometer collecting divergent emitted end at focus “image slicer.” However,...
BackgroundThere is no consensus on reporting light characteristics in studies investigating non-visual responses to light. This project aimed develop a checklist for laboratory-based investigations the impact of physiology.MethodsA four-step modified Delphi process (three questionnaire-based feedback rounds and one face-to-face group discussion) involving international experts was conducted reach items be included checklist. Following process, resulting tested pilot phase with independent...
Abstract Study Objectives Light is the main time cue for human circadian system. Sleep and light are intrinsically linked; exposure patterns can influence sleep patterns. However, metrics quantifying regularity lacking, relationship between underexplored. We developed new demonstrated their utility in adolescents, across school term vacation. Methods Daily sleep/wake were measured using wrist actigraphy 75 adolescents (54% male, 17.17 ± 0.83 years) over 2 weeks of a subsequent 2-week The...
Single−crystal fibers of Nd:YAG have been grown in diameters as small as, but not limited to, 50 μm by a pedestal growth (modified zone melting) technique. Room−temperature cw laser operation has achieved with 0.5−1−cm−long samples. The method is directly applicable to the single−crystal various materials for devices covering wide range applications, especially optical communications.
The OH-stretching fundamental, and the first, second, third OH overtone vibrations have been examined using pure, GeO2-doped, graded index, fused silica optical fibers having contents from &lt;1 ppm to ≳103 ppm. previously reported component substructure of fundamental contour was found be repeated in overtones, along with a set involving silica. Several new were uncovered assigned. Examinations deuterated samples helped verify assignments. spectral broadening produced by GeO2...
Multimode liquid-core quartz fibers, potentially useful for long-distance optical communication, have been constructed. The transmission loss of these fibers has measured between 6000 and 11 000 Å. Fibers filled with tetrachloroethylene or a mixture equal parts by volume carbon tetrachloride 20 dB/km less 8400 8600 Å 10 400 These bands are particular interest because within them operate highly promising oscillators such as the GaAs diode Nd: YAG laser. An absorption peak 80 at 9600 is...
Get PDF Email Share with Facebook Tweet This Post on reddit LinkedIn Add to CiteULike Mendeley BibSonomy Citation Copy Text M. A. Saifi, S. J. Jang, L. G. Cohen, and Stone, "Triangular-profile single-mode fiber," Opt. Lett. 7, 43-45 (1982) Export BibTex Endnote (RIS) HTML Plain alert Save article
The utility of Raman spectroscopy as a means characterizing the properties pure and doped fused silica has been investigated. Laser-Raman spectra were obtained by forward scattering from solid optical fibers ∼35 to 85 m in length using 514.5 nm excitation with an “image slicer” Cary model 81 instrument. Clad unclad having SiO 2 -GeO -B O 3 cores examined. also bulk samples glasses, including GeO , B various compositions . addition dopants was found alter spectrum both appearance new bands,...
Single-crystal fibers have been grown from high-purity 1.5 wt% Nd2O3 : Y2O3 powder mixtures, and short lengths of the fiber in dielectric mirror resonators evaluated as lasers at both 1.07- 1.35-μm wavelength. The laser transition cross sections were approximately equal two wavelengths, they about two-thirds section Nd YAG 1.31 μm. fluorescence lifetime samples was 340 μsec. Loss material 3% per cm. absorption spectrum 0.7 to 1.0 μm spectra for 4F3/2→4I9/2, 4F3/2→4I11/2, 4F3/2→4I13/2...
cw laser action has been obtained using as-grown single-crystal Nd:YAG fibers end-pumped by a single high-radiance LED. The were 0.5 cm long and 80 μm in diameter, the diameter of LED luminous area was 85 μm. lowest threshold observed at diode drive current 45 mA.
Get PDF Email Share with Facebook Tweet This Post on reddit LinkedIn Add to CiteULike Mendeley BibSonomy Citation Copy Text J. Stone and C. A. Burrus, "Neodymium-Doped Fiber Lasers: Room Temperature cw Operation an Injection Laser Pump," Appl. Opt. 13, 1256-1258 (1974) Export BibTex Endnote (RIS) HTML Plain alert Save article
Shift work is highly prevalent and associated with significant adverse health impacts. There substantial inter-individual variability in the way circadian clock responds to changing shift cycles. The mechanisms underlying this are not well understood. We tested hypothesis that light-dark exposure a contributor variability; when combined diurnal preference, relative timing of light accounted for 71% individual phase response night work. These results will drive development personalised...
Practical alternatives to gold-standard measures of circadian timing in shift workers are needed. We assessed the feasibility applying a limit-cycle oscillator model human pacemaker estimate phase 25 nursing and medical staff field setting during transition from day/evening shifts (diurnal schedule) 3-5 consecutive night (night schedule). Ambulatory measurements light activity recorded with wrist actigraphs were used as inputs into model. Model estimations compared urinary...
There is large interindividual variability in circadian timing, which underestimated by mathematical models of the clock. Interindividual differences timing have traditionally been modeled changing intrinsic period, but recent findings reveal an additional potential source variability: light sensitivity. Using established model human clock with real-world recordings, we investigated whether changes sensitivity parameters or period could capture between and within individuals. Healthy...
To compare blood loss and transfusion rates in geriatric hip fracture patients on direct oral anticoagulants undergoing surgery ≤ 24 hours from admission (Expedited group) versus 24-72 (Delayed group). Design: Retrospective cohort study. Level I Trauma Center. Patients aged ≥ 65 with a femoral neck, intertrochanteric, or subtrochanteric (AO/OTA 31A, 31B, 32) factor Xa inhibitors (apixaban rivaroxaban) prior to April 2014 2024 were included.Outcome Measures Comparisons: Primary outcomes...
cw Raman amplification has been observed in a hollow fused silica fiber, inside diameter 5 μm, m long, filled with benzene. Using krypton laser pump, of the 992−cm−1 Stokes line obtained at pump wavelengths 5682, 6471, and 7525 Å. The powers determined by measuring slightly attenuated output from fiber were 17, 25, 17 mW, respectively. corresponding amounts power input before launching optics 70, 85, 75 mW.
We aimed to characterize objective and subjective sleepiness driving events during short work commutes examine the impact of circadian homeostatic factors across different shift types in a worker population. Thirty-three nurses were monitored for 2 weeks over day (07:00–15:30), evening (13:00–21:30), night shifts (21:00–07:30). Sleep was measured via daily sleep logs wrist actigraphy. Driving completed each commute, reporting predrive Karolinska Sleepiness Scale (KSS). Ocular data from...
During the COVID-19 pandemic, schools around world rapidly transitioned from in-person to remote learning, providing an opportunity examine impact of vs learning on sleep, circadian timing, and mood. We assessed sleep-wake timing using wrist actigraphy sleep diaries over 1-2 weeks during (n = 28) 58, where n 27 were repeat assessments) in adolescents (age M ± SD 12.79 0.42 years). Circadian was measured under a single condition each individual salivary melatonin (Dim Light Melatonin Onset;...