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Mechanical Engineering. 2006;128(10):24-27. doi:10.1115/1.2006-OCT-1.
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This paper describes the use of nanotechnology in detection of disease at its earliest stage. Nanotechnology makes it possible to envision new devices that can deliver a 100-fold and even larger increase in sensitivity over current diagnostic techniques. Very small-scale diagnostic devices have been designed depending on the transduction mechanism—mechanical or electrical—of the biomedical stimulus. Devices that use nanocantilevers, nanowires, and nanoparticles have been built and tested, and are currently under development. The nanowire-based devices are nanometer-wide semiconductor wires coated with molecules arranged in parallel on the bottom of a microfluidic chamber where a blood sample is introduced for analysis. The binding event among the molecules on the wire and the biomarkers in the sample produces a change in the electrical conductivity of the wire that can be measured in real time and related to the amount of biomarkers in solution.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 2006;128(10):28-32. doi:10.1115/1.2006-OCT-2.
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This paper focuses on the development of modern metal-on-metal hips implants. Their large bearings mimic natural biomechanics and let patients remain active. Metal rubbing on metal creates nanoscale wear debris. The particles appear small enough for some cobalt and chrome to end up as ions. Both metals have the potential to cause cancer. Device manufacturers are scrambling after alloys that leave behind less debris. Some have also introduced ceramic hips. Ceramics are highly biocompatible and so hard and wear-resistant that they are likely to outlast metal. The ceramics used in hip implants are a triumph of materials science. The industry is moving toward zirconia-toughened alumina. It is stronger than conventional alumina and designers can slim down cup liners and use larger ceramic femoral bearings.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 2006;128(10):34-36. doi:10.1115/1.2006-OCT-3.
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This paper describes an automated system to address disconnect between the design and analysis programs. The disconnect between computer-aided design (CAD) and analysis occurs because one system is powered by geometrical information and the other is not. One system is meant to handle geometry, while the other creates a mesh and does not rely on geometry in the same way that CAD does. Engineering software developers coming up with a design-analysis workaround by building design automation into their CAD packages. This method gives engineers vital information about the part from the get-go. The information is gleaned from the past designs for similar parts and can be automatically included in the new model. Such automated systems capture expert knowledge and reapply it to other models. The system might ask engineers to answer several questions about what they intend to design before they even start. The automated system would help engineers build parts upfront that would meet criteria for phenomena from varied disciplines, including fluid, structural, or thermal analysis.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 2006;128(10):38-41. doi:10.1115/1.2006-OCT-4.
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This paper describes the progress made in lens making for telescopes. The use of rotating equipment was an important innovation in lens making, although it is possible to grind lenses entirely by hand. After grinding, the lens was polished, sometimes using the same lap that had been used to shape it. It required preparing the lap surface to remove roughness. In some cases, it was done by overlaying the surface of the lap with a specially prepared paper. Pitch was poured on the lens surface and, when it hardened, was removed, creating a tool exactly matching the curvature of the lens. When it became possible to make generalizations about the performance of telescopes, it became obvious that the spherical aberration due to the shape of simple lenses was a factor that limited optical quality. The vast majority of amateur-made telescopes are reflectors.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 2006;128(10):42-44. doi:10.1115/1.2006-OCT-5.
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This paper discusses the designs and development of human-powered vehicles (HPV). Several new records have been set with what are called HPV. In the space of three weeks, Fast Freddy Markham sets a new record for the longest hour-long ride-53.34 miles-an d Greg Kolodziejzyk put more miles under his tires in 24 hours than anyone in human-powered history, 650.5. Markham and his foes have a chance to ride their HPVs only at competitions, since they need a crew to help get them in and out of their sealed shells. Weaver has set many speed records himself and has beaten Markham in several top speed races. Markham's approach makes the most sense for an hour-long race, where there is plenty of time for experience to shine and technology to break down. It is found that while Markham's hour-long record is likely to remain unbroken for sometime Weaver still holds the US record for top speed, having hit 78.02 mph in his Cutting Edge in 2001.

Commentary by Dr. Valentin Fuster

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