The mechanical properties of guidewires
Stiffness is always one of two factors that determine frictional resistance. The other factor, the coefficient of friction, depends on the surface characteristics. Teflon coating reduces the sliding friction to one-half, and a hydrophilic plastic coat to about one-sixth compared with steel.
Systematic evaluation of hybrid guidewires: shaft stiffness, lubricity, and tip configuration.
OBJECTIVE
To conduct a comparison of physical and mechanical properties for 5 commonly used guidewires to assess advantages of wires for specific applications.


METHODS
Tests on guidewires (0.035" diameter; straight, flexible tip) included tip bending, shaft buckling, lubricity, and tip puncture measurements. Guidewires included 2 hybrid wires: the U-Nite (Bard Urological, Covington, GA) and the Sensor (Boston Scientific, Natick, MA). Our aim was to compare the stiffness of these hybrid wires with the standard Amplatz SuperStiff (Boston Scientific). Our second aim was to compare the hydrophilic tip of the hybrid wires with 2 traditional hydrophilic guidewires: the NiCore (Bard Urological) and RadiFocus glidewire (Boston Scientific).


RESULTS
The Amplatz SuperStiff had a significantly stiffer shaft than either hybrid wire, with a buckling force of 1.81 ± 0.91 N compared with the Sensor (0.80 ± 0.29 N, P = .0002) and the U-Nite (0.77 ± 0.29 N, P < .0001). The Boston Scientific guidewire tips were less stiff than the Bard guidewires, requiring up to 48% less force to bend when encountering resistance (P < .0001). The U-Nite had the highest lubricity (0.09 ± 0.03 N, P < .0001) and roundest tip of all the guidewires tested. The RadiFocus required the greatest puncture force (1.80 ± 0.27 N, P < .0001) of all the guidewires tested.


CONCLUSION
Hybrid wires offer a combination of a stiffer shaft and hydrophilic tip. The Amplatz SuperStiff remains the stiffest wire and as such is best suited for placement of ureteral access sheaths or larger stents. The Boston Scientific wires require less force to "bend" around a point of obstruction compared with the Bard wires. The Boston Scientific RadiFocus requires the greatest force to puncture aluminum foil.
Investigation of International Standard, International Electrotechnical Commission, IEC 62305 and Indian Standard IS 2309 in positioning the Air Terminals (ATs)
From 18th Century onwards, many scientists and researchers across the globe have conducted experiments and researches related to the subject called Lightning and as a result they have acquired success in protecting the structures against lightning strokes to a great extent. However, the science behind lightning has not been completely discovered and therefore any design of lightning protection scheme can’t be certified as cent percent safe. Here in this paper, a cuboid equivalent to a rectangular industrial building has been taken into consideration. Lightning Protection Scheme for the same has been designed in two ways: i) based on the Protective Angle Method and Rolling Sphere Method as per International Standard IEC 62305 and ii) based on the Protective Angle Method as per Indian Standard IS 2309. This paper mainly focuses on the comparison of those two designs which ultimately discloses the difference in safety level that we are having by adopting a particular standard.