objective: infection control is one of the important aspects in dentistry. oral and maxillofacial surgery is one of the most sensitive fields in dentistry in which infection control is important a sterile surgical set is imperative. manufacturers only guarantee the sterility of the anesthetic not the sterility of its outer surface. they recommend alcohol to sterile the outer surface (especially...

The quadrics are all surfaces that can be expressed as a second degree polynomialin x, y and z. We study the Gauss map G of quadric surfaces in the 3-dimensional Euclidean space R^3 with respect to the so called L_1 operator ( Cheng-Yau operator □) acting on the smooth functions defined on the surfaces. For any smooth functions f defined on the surfaces, L_f=tr(P_1o hessf), where P_1 is t...

In this paper, we classify surface at a constant distance from the edge of regression on translation surfaces of Type 1 in the three dimensional simply isotropic space I^1_3 satisfying some algebraic equations in terms of the coordinate functions and the Laplacian operators with respect to the first, the second and the third fundamental form of the surface. We also give explicit forms of these ...

in this paper, we study cyclic surfaces in 5 1 e generated by homothetic motions of a lorentziancircle. the properties of these cyclic surfaces up to first order are investigated. we show that, as it is shown ine5 , cyclic 2-surfaces in 5 1 e , in general, are contained in canal hypersurfaces. finally, we give an example.

Over the past decade, the civil engineering community has ever more realized the importance and perspective of reliability-based design optimization (RBDO). Since then several advanced stochastic simulation algorithms for computing small failure probabilities encountered in reliability analysis of engineering systems have been developed: Subset Simulation (Au and Beck (2001) [2]), Line Sampling...

background: the role of the hospital environment as a source of dissemination of pathogens is critical. environmental surfaces in the intensive care units (icus) are suitable for the growth of gram-negative bacteria that normally circulate between the environment and patients and can cause outbreaks of nosocomial infections. in this study, the prevalence of gram-negative bacilli in the environm...

titania nanotubes (tnt) prepared by anodization of ti foils were used for water splitting in a standalone cell. the concentration polarization between the anode side (1m naoh) and cathode side (0.5 m h2so4) ensured that the water splitting reaction could take place with no external bias and separate h2 and o2 evolution could be achieved. the destruction of tnt structures under 365 nm uv irradia...

in this paper, we consider weighted composition operators betweenmeasurable differential forms and then some classic properties of these operators are characterized.

in this paper, the time-like hyperruled surfaces in the minkowski 4-space and their algebraicinvariants are worked. also some characteristic results are found about these algebraic invariants.

in this paper, the dual area vector of a closed dual spherical curve is kinematically generatedand the dual steineer vector of a motion are extensively studied by the methods of differential geometry.jacobi’s theorems, known for real curves, are investigated for closed dual curves. the closed trajectorysurfaces generated by an oriented line are fixed in a moving rigid body in ir3 , in which the...