Orientation distributions of garnet and omphacite in eclogite from the ultra-high pressure Dabie Shan belt in east-central China were determined from neutron diffraction data by the Rietveld method. Diffraction spectra were recorded in 16 sample orientations with seven detectors, with a kappa-geometry texture goniometer at the time-of-¯ight (TOF) neutron facility at the Intense Pulsed Neutron Source (IPNS). The textures of the two minerals were extracted simultaneously from 16 Â 7 = 112 diffraction spectra, covering a large portion of the pole ®gure. The texture analysis was performed both with the Williams± Imhof±Matthies±Vinel (WIMV) method and the harmonic method, implemented in the program package MAUD. The incomplete pole-®gure coverage introduced arti®cial oscillations in the case of the harmonic method. The discrete WIMV method produced better results, which illustrate a more or less random orientation distribution for cubic garnet. Apparently elongated grains turned out to be layers of randomly oriented crystals. Monoclinic omphacite displays a sharp texture, with [001] parallel to the lineation direction. The texture data obtained by neutron diffraction were veri®ed with EBSP (electron backscatter pattern) measurements.

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Novel composite scaffolds were produced using long continuous bidirectional fibers embedded in an electrospun matrix, with the aim of using them in soft tissue engineering applications. The fibers are of polydioxanone and the matrix of polylactic acid. The novel manufacturing method consists of direct electrospinning performed on both sides of a collector that supports the already arranged fibers. The scaffolds were tested in vitro using 3T3 mouse fibroblasts as-obtained or functionalized with biotin or poly (dopamine). Functionalization did not significantly affect cells attachment, metabolic activity, or proliferation, but poly (dopamine) was proven to be effective in inducing hydrophilicity to the surface.

Although titanium is considered to be the most successful metal for uncemented endosseous implants, its biocompatibility may be unsatisfactory in certain clinical cases. As an early osseointegration is essential in order to reduce the implant failure risk, the bioactive fixation becomes the appropriate solution for bone applications. The method requires bioactive materials such as hydroxyapatite (HA) to facilitate the chemical bonding to tissue. The present work refers to Ti-HA composites designed for endosseous implants and obtained through the classic PM route. Grade 1 c.p. Ti powder obtained through the hydriding – milling – dehydriding process, 63 - 100 μm grain size, was used. Sol-gel HA powder, grain size of less than 100 μm, was obtained through the sol-gel method. Blends of Ti and 5 to 50% HA were compacted in a rigid die (0.5 cm2), without the use of any lubricant, with 400, 500 and 600 MPa, then vacuum sintered (10-6 torr) at 1160°C for 60 minutes. Samples are well sintered with a compactness that increases with the applied compaction pressure. A transition layer can be seen in the EDX at the interface between the Ti matrix and the HA particles and is expected to increase the overall mechanical stability of compacts. The pores, essential for osseointegration, are interconnected, with irregular shapes and sizes that reach 100 μm, the critical size needed for the formation of a vital new bone. The HA content has to be limited to 30%, not to lead to an excessive brittleness. The biologic viability of compacts was assessed by immersion for 7 days into a simulated body fluid (SBF). The subsequent XRD analyses have proven that a new HA layer is formed on the surface of samples. This layer is essential for accelerating the cellular response of osteoblasts in the body.

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