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Laser Engineered Net Shaping (LENS) is a novel manufacturing process for fabricating metaI parts directly from Computer Aided Design (CAD) solid models. The process is similar to rapid prototyping technologies in its approach to fabricate a solid component by layer additive methods. However, the LENS technology is unique in that fully dense metal components with material properties that are similar to that of wrought materials can be fabricated. The LENS process has the potential to dramatically reduce the time and cost required realizing functional metal parts. In addition, the process can fabricate complex internal features not possible using existing manufacturing processes. The real promise of the technology is the potential to manipulate the material fabrication and properties through precision deposition of the material, which includes thermal behavior control, layered or graded deposition of multi-materials, and process parameter selection.

Use of high numerical aperture focusing with negative longitudinal spherical aberration is shown to enable deep (> microm), high aspect ratio, nano-scale-width holes to be machined into the surface of a fused-silica (SiO(2)) substrate with single pulses from a 200 fs, 4 microJ Ti-Sapphire laser source. The depths of the nano-holes are characterized by use of a non-destructive acetate replication technique and are confirmed by imaging of sectioned samples with a dual focused ion beam/scanning electron microscope.

Aim To evaluate the efficacy of electrically conductive, biocompatible composite scaffolds in modulating the cardiomyogenic differentiation of human mesenchymal stem cells (hMSCs). Materials & methods Electrospun scaffolds of poly(ε-caprolactone) with or without carbon nanotubes were developed to promote the in vitro cardiac differentiation of hMSCs. Results Results indicate that hMSC differentiation can be enhanced by either culturing in electrically conductive, carbon nanotube-containing composite scaffolds without electrical stimulation in the presence of 5-azacytidine, or extrinsic electrical stimulation in nonconductive poly(ε-caprolactone) scaffolds without carbon nanotube and azacytidine. Conclusion This study suggests a first step towards improving hMSC cardiomyogenic differentiation for local delivery into the infarcted myocardium.