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Composition, structure and properties of the products of self-propagating high-temperature synthesis (SHS) are characterised by some distinctive features. High heating rate, fast cooling after rapid completion of the reactions and steep temperature gradients make SHS very effective in producing in situ composites with ceramic reinforcements. In the present work, hardfacing of AISI304 substrates has been done by fabricating a hard ternary ceramic matrix composite layer of Al2O3–TiB2–TiN by laser surface treatment at different scan speeds. The formation of the surface layer is due to laser-triggered SHS followed by laser melting. A mixture of Al, TiO2 and hBN has been used as a precursor for the SHS reaction. The study of the microstructure of the as-fabricated composite layer reveals the co-existence of TiB2 and TiN phases in the nanometric size range in Al2O3 matrix. The presence of all the phases has been confirmed by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), high resolution transm...

To evaluate the effects of conditioned medium of adipose-derived stem cells (ADSC-CM) on efficacy and side effects after fractional carbon dioxide laser resurfacing (FxCR) when treating subjects with facial atrophic acne scars or with skin rejuvenation needs.Twenty-two subjects were enrolled in the study and divided into two groups. Nine subjects were included in skin rejuvenation group and thirteen subjects were included in acne scar group, and all subjects underwent three sessions of FxCR. ADSC-CM was applied on FxCR site of one randomly selected face side. Evaluations were done at baseline, 1 week after first treatment, and 1 month after each treatment. The outcome assessments included subjective satisfaction scale; blinded clinical assessment; and the biophysical parameters of roughness, elasticity, skin hydration, transepidermal water loss (TEWL), and the erythema and melanin index. Biopsies taken from one subject in skin rejuvenation group were analyzed using hematoxylin and eosin, Masson's Trichrome, and Gomori's aldehyde fuchsin staining.ADSC-CM combined with FxCR increased subject satisfaction, elasticity, skin hydration, and skin elasticity and decreased TEWL, roughness, and the melanin index in both acne scars and skin rejuvenation groups. Histologic analysis showed that ADSC-CM increased dermal collagen density, elastin density, and arranged them in order.ADSC-CM with FxCR is a good combination therapy for treating atrophic acne scars and skin rejuvenation.JSPH2012-082 - Registered 14 Feb 2012.

The present work investigates the method of depositing a ceramic coating on the surface of aluminum by means of electrical discharge coating (EDC) in electrical discharge machining (EDM). The present study makes use of powder metallurgy (P/M) green compacts made of titanium, boron carbide, and aluminum (Ti + B4C + Al) powder as the EDM tool for surface modification of aluminum workpieces. EDM process was carried out with different tool parameters like composition of the electrode material, compaction pressure of the green compacts, and different settings of the process variables like peak current and pulse duration setting. Responses observed were material deposition rate (MDR), tool wear rate (TWR), and average layer thickness (LT). Experiments were designed and carried out using Taguchi L18 orthogonal array. The most influential parameter for responses MDR, TWR, and LT was found to be peak current (Ip) with a percentage contribution of 60.72%, 59.52%, and 42.09%, respectively. In addition, various other...