Metallic tracheal stents have been used in the treatment of paediatric tracheomalacia for more than a decade. We describe a case in which critical airway obstruction occurred during removal of a welded tracheal stent using a rigid bronchoscope under general anaesthesia. Life-saving cardiopulmonary bypass was instituted urgently, and the welded stent was then removed successfully by directly ope...

OBJECTIVE To compare the deflection load characteristics of homogeneous and heterogeneous joints made by laser welding using various types of orthodontic wires. MATERIALS AND METHODS Four kinds of straight orthodontic rectangular wires (0.017 inch × 0.025 inch) were used: stainless-steel (SS), cobalt-chromium-nickel (Co-Cr-Ni), beta-titanium alloy (β-Ti), and nickel-titanium (Ni-Ti). Homogene...

It is important to have students take notes so as to increase their concentration. We examined how students take notes by providing paper notebooks and PC notebooks, each of which are provided with a fill-in-blanks section and a free writing section. The results show that, 93.9% of the fill-in-blanks areas of paper and PC notebooks were written, while only 14.0% of the free writing areas were. ...

The objective of this study was to investigate the effects of cryo-treatment on the microstructure, corrosion behavior, and mechanical properties of Ti before and after laser welding. The microstructure was studied by optical microscopy. It was found that the grain size for Ti became smaller after cryo-treatment. Cryo-treatment could also refine and stabilize the crystal lattice structure and d...

The benefits of laser welding include higher production values, deeper penetration, speeds, adaptability, and power density. These characteristics make a superior process. Many industries are aware the switching to lasers. For example, metal-joining is migrating modern industrial technology due improved yields, design flexibility, energy efficiency. However, for an process be optimized intellig...

We define an invariant of welded virtual knots from each finite crossed module by considering crossed module invariants of ribbon knotted surfaces which are naturally associated with them. We elucidate that the invariants obtained are non-trivial by calculating explicit examples. We define welded virtual graphs and consider invariants of them defined in a similar way. 2000 Mathematics Subject C...

Abstract In the field of mobility, increased safety and emission requirements lead to steadily rising demands on materials used their performance. Over last decades, 5000 6000 series aluminum alloys have become more attractive as lightweight material due beneficial weight strength ratio. The 7000 offers extended potential its high strength. Until now, this class has not been widely in mass prod...

Purpose of research is to develop and test a technique perform an experimental study the vibration strength D16 aluminum alloy joints welded applying resistance spot welding. Methods. Test coupons were made from 1 mm thick sheet blanks A feature proposed implementation symmetrical loading cycle. During tests, number cycles failure depending on range vibrations was recorded. Annealing thermomech...