This study evaluated the efficiency of air abrasion alone and associated with phosphoric acid etching on tensile bond strength of a single-bottle adhesive/indirect composite restorative system (Bond 1/Alert) to human enamel. Forty enamel surfaces from extracted human third molars were assigned to 4 groups (n= 10). Mach 4.1 (Kreativ Inc.) air abrasion equipment was used for 20 s. A special syste...

OBJECTIVE To examine the reproducibility, responsiveness and concurrent validity of the six-minute walk test (6MWT) when tested outdoors in patients' own neighbourhoods using a global positioning system (GPS) or a measuring wheel. METHODS A total of 27 chronic stroke patients, discharged to their own homes, were tested twice, within 5 consecutive days. The 6MWT was conducted using a GPS and a...

In order to study passing ability of lunar rover in lunar soil, the mechanical parameters between lunar wheel and lunar soil should be analyzed. The mechanical parameters can reflect the mechanical relationship between lunar rover wheel and regolith. These parameters include sinkage, drawbar pull, driving torque, motion resistance and slip. In this paper, these parameters are measured by soil b...

Self-healing of the superhydrophobic cotton fabric (SCF) obtained by the radiation-induced graft polymerization of lauryl methacrylate (LMA) and n-hexyl methacrylate (HMA), can be achieved by ironing. Through the steam ironing process, the superhydrophobicity of the SCFs will be regenerated even after the yarns are ruptured during the abrasion test under a load pressure of 44.8 kPa. SCFs made f...

This paper presents a design for stair-climbing using a wheel that can split into segments and walk up stairs or surmount other obstacles often found where humans traverse, while still being able to retain a perfectly round shape for traveling on smooth ground. Using this change of configuration, staircases with a wide range of dimensions can be covered efficiently and safely. The design, named...

Wheel defects on trains, such as flat wheels and out-of-roundness, inevitably jeopardize the safety of railway operations. Regular visual inspection and checking by experienced workers are the commonly adopted practice to identify wheel defects. However, the defects may not be spotted in time. Therefore, an automatic, remote-sensing, reliable, and accurate monitoring system for wheel condition ...

The aim of this study was to test the effect of fluoride rinsing on the prevention of toothbrush abrasion of softened enamel in situ. For softening, the samples were immersed in 0.1 M citric acid (pH 3.5) for 3 min. Eight test subjects had to make 5 runs in which 4 slabs per run were attached to intraoral appliances. They were as follows: (1) no softening, no fluoride rinsing (control 1); (2) s...

STATEMENT OF PROBLEM Flexural strength, hardness, surface roughness, discoloration, and abrasion resistance are important properties of veneering composite resins. Recently introduced veneering resins are purported to have enhanced mechanical properties due to their composition, but their long-term durability is not known. PURPOSE The purpose of this study was to test the impact of aging on 3...

OBJECTIVES This study evaluated the influence of air-particle abrasion protocols on the surface roughness (SR) of zirconia and the shear bond strength (SBS) of dual-polymerized resin cement to this ceramic. MATERIALS AND METHODS Sintered zirconia blocks (n = 115) (Lava, 3M ESPE) were embedded in acrylic resin and polished. The specimens were divided according to the 'particle type' (Al: 110 µ...

In recent years, there has been a huge demand for innovative methods to upcycle waste materials. This study aims explore and evaluate the effect of using low-density polyethylene (w-LDPE), collected from plastic bags domestic purposes, on mechanical properties dense Thin Asphalt Overlay (TAO). Waste materials have deemed appropriate in development asphalt pavement mixtures, due expected enhance...