The Effect of Water Storage on the Bending Properties of Esthetic, Fiber-Reinforced Composite Orthodontic Archwires

Objective: To study the effect of water storage on the bending properties of fiber-reinforced composite archwires and compare it to nickel-titanium (NiTi), stainless steel (SS), and beta-titanium archwires. Materials and Methods: Align A, B, and C and TorQ A and B composite wires from BioMers Products, 0.014-, 0.016, and 0.018-inch, and 0.019 × 0.025-inch NiTi, 0.016-inch SS, and 0.019 × 0.025-inch beta-titanium archwires were tested (n  =  10/type/size/condition). A 20-mm segment was cut from each end of the archwire; one end was then stored in water at 37°C for 30 days, while the other was stored dry. The segments were tested using three-point bending to a maximum deflection of 3.1 mm with force monitored during loading (activation) and unloading (deactivation). Statistical analysis was completed via two-way analysis of variance with wire and condition (dry and water-stored) as factors. Results: In terms of stiffness and force delivery during activation, in general: beta-titanium was \u3e TorQ B \u3e TorQ A \u3e 0.019 × 0.025-inch NiTi and 0.016-inch SS \u3e Align C \u3e 0.018-inch NiTi \u3e Align B \u3e 0.016-inch NiTi \u3e Align A \u3e 0.014-inch NiTi. Water exposure was detrimental to the larger translucent wires (Align B and C, TorQ A and B) because they were more likely to craze during bending, resulting in decreased forces applied at a given deflection. Align A and the alloy wires were not significantly (P\u3e .05) affected by water storage. Overall, the alloy wires possessed more consistent force values compared to the composite wires

Observation of enhanced optical spring damping in a macroscopic mechanical resonator and application for parametric instability control in advanced gravitational-wave detectors

We show that optical spring damping in an optomechanical resonator can be enhanced by injecting a phase delay in the laser frequency-locking servo to rotate the real and imaginary components of the optical spring constant. This enhances damping at the expense of optical rigidity. We demonstrate enhanced parametric damping which reduces the Q factor of a 0.1-kg-scale resonator from 1.3×10^5 to 6.5×10^3. By using this technique adequate optical spring damping can be obtained to damp parametric instability predicted for advanced laser interferometer gravitational-wave detectors

Impact of the Casimir-Polder Potential and Johnson Noise on Bose-Einstein Condensate Stability near Surfaces

We investigate the stability of magnetically trapped atomic Bose-Einstein condensates and thermal clouds near the transition temperature at small distances 0.5 microns < d < 10 microns from a microfabricated silicon chip. For a 2 microns thick copper film the trap lifetime is limited by Johnson-noise induced currents and falls below 1 s at a distance of 4 microns. A dielectric surface does not adversely affect the sample until the attractive Casimir-Polder potential significantly reduces the trap depth.Comment: 4 pages, 5 figures, and submitted to Physical Review Letter

The Ameliorating effect of uncooked beans diet in CD-1 mice

Beans contain serotonin and its precursor, 5-Hydroxytryptophan which have neurobehavioral actions on memory, anxiety, mood and pain. This study was therefore, designed to investigate the ameliorating effect of uncooked beans on pain sensation using three groups of Swiss white mice (control and test) weighing 18g-35g (n=10 each).The control group received normal rodent chow, while the test group received 50g of uncooked beans in 50g of rodent chow per day and serotonin precursor (5HTP) (0.2mg/50g w/w) diet. Water was given adlibitum while daily food and water intake, as well as body weight changes, were monitored during the 30-day study. The formalin tests were used to assess pain sensation. The results showed that in the formalin test, the frequency and duration of paw attention in both phases of the test was significantly lower (P&lt; 0.05) compared to the control group. The duration and frequency of paw licks (P&lt;0.05) was also significantly lower in the uncooked beans diet and serotonin precursor group compared to the control. Therefore, consumption of uncooked beans diet may decrease pain sensation.    Â

Properties of a highly birefringent photonic crystal fiber

Author name used in this publication: J. JuAuthor name used in this publication: W. JinAuthor name used in this publication: M. S. Demokan2003-2004 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

Design of single-polarization single-mode photonic crystal fiber at 1.30 and 1.55 µm

Author name used in this publication: M. Suleyman Demokan2005-2006 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe