RESUMEN
Typically, archers prepare two sets of bows for competitions in case of bow breakage, but if the limbs of the bow break during a match, archers can become psychologically disadvantaged, leading to potentially fatal consequences. Archers are very sensitive to the durability and vibration of their bows. While the vibration-damping properties of Bakelite® stabilizer are excellent, its low density and somewhat lower strength and durability are disadvantages. As a solution, we used carbon fiber-reinforced plastic (CFRP) and glass fiber-reinforced plastic (GFRP) for the archery limb with stabilizer, commonly used for the limbs of the bow, to manufacture the limb. The stabilizer was reverse-engineered from the Bakelite® product and manufactured using glass fiber-reinforced plastic in the same shape as the existing product. Analyzing the vibration-damping effect and researching ways to reduce the vibration that occurs during shooting through 3D modeling and simulation, it was possible to evaluate the characteristics and the effect of reducing the limb's vibration by manufacturing archery bows and limbs using carbon fiber- and glass fiber-reinforced composites. The objective of this study was to manufacture archery bows using CFRP and GFRP, and to assess their characteristics as well as their effectiveness at reducing limb vibration. Through testing, the limb and stabilizer that were produced were determined to not fall behind the abilities of the bows currently used by athletes, and they also exhibited a noticeable reduction in vibrations.
RESUMEN
In nasal septal deviation, the deviated narrow side is more frequently combined with sinusitis due to the mechanical obstruction of ostiomeatal unit. The purpose of this study was to determine whether reduced airflow has a harmful effect on nasal inflammation and the development of rhinosinusitis. Twenty-three healthy New Zealand white rabbit were used. One side of the nostril was closed in 15 rabbits and 5 rabbits served as control. Rabbits were sacrificed at 4, 8 and 12 weeks. The anterior maxillary and septal mucosa were obtained for EM and LM study. Mucociliary clearance rate was measured using the India ink method. At 4 weeks, the opened side mucosa showed ciliary losses and ulcerations in the mucosa, but at 8 and 12 weeks, the closed side showed more severe ulceration and ciliary loss than open side. The mucociliary clearance rate was 12.3 mm/min in the control group, but the open side was 8.7 and 7.1 mm/min and the closed side was 4.7 and 6.4 mm/min at 4 and 8 weeks, respectively. Electron microscopy showed many abnormal cilia at 8 weeks in both sides. These observations suggest that inadequate airflow is an important causative factor of nasal and sinus infection, and that patients with septal deviation have a similar chance of developing sinusitis in either side.