The Effect of Ca and Mg on the Microstructure and Tribological Properties of YPbSn10 Antifriction Alloy

An alloy YPbSn10 used for antifriction applications was synthetized in a furnace and the structure was improved by a microalloying technique. The elements chosen for microalloying were Ca 2%wt and Mg 2%wt. The microalloying technique proved to have good results in producing alloys with homogeneous composition, with a good distribution of the hard phase. The alloys were produced in a furnace and samples were collected and investigated. The structural properties were investigated using an SEM technique with EDS analyses and XRD to identify the compounds formed during alloying. The tribological properties were investigated to see the improvement obtained in this area. The results revealed a homogeneous composition for both samples, alloyed with Ca or with Mg, and the friction coefficient was reduced after the microalloying with almost 20%

Use of Collagen Scaffolds in Conjunction with NPWT for the Care of Complex Wounds: Clinical Report

Open wounds treatment is very often a challenge for both the physician and patient. They require long term complex treatment with surgical debridement, dressing changing, additional therapies including expensive medication, with a high risk of failure. The most difficult to treat are the diabetic wounds and those that are associated with advanced arterial disease. In these special cases, the peripheral vascularization is severely impaired and the complications are imminent. Sixteen patients were selected from those appearing to our hospital departments of orthopedic and plastic surgery. Inclusion criteria included patients with a recurrent mixed fibrotic and granular wound base following trauma or diabetes, in which NPWT was indicated, without exclusion criteria. Patients enrolled were treated with regularly scheduled NPWT dressing change and using of a collagen scaffold. Patients were followed until healing, with visual representations of wound progression and time to full healing recorded. Both applications of these therapies appeared to accelerate the wound healing by clearing degenerative fibrous tissue and expediting wound granulation without additional complication. Some of the patients were healed partially and plastic surgery techniques were applied. Use of collagen scaffolds in conjunction with negative pressure wound therapy in the care of complex wounds is a reliable and effective method combining both the new granular tissue formation capacity of the scaffold to hold osteoblasts. In our experience, we have noticed that the patients benefit greatly when collagen scaffolds is combined with NPWT. It is our belief that this combination therapy combines the molecular clearing of non-viable collagen with the wound granulation necessary to advance complex wounds in healing