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Background: The use of mesenchymal stem cells (MSCs) for the treatment of knee osteoarthritis (OA) has gained recent interest in the orthopaedics community. Purpose: To review the literature to evaluate the efficacy of umbilical cord–derived MSCs in the treatment of OA of the knee joint. Study Design: Systematic review; Level of evidence, 4. Methods: We searched the PubMed, Cochrane Library, and Embase databases to identify studies with evidence levels from 1 to 4 that evaluated the clinical efficacy of human umbilical cord–derived MSC (hUC-MSC) injections for knee OA. The search phrase used was "umbilical cord knee osteoarthritis." In the studies reviewed, patients were assessed based on the macroscopic International Cartilage Regeneration & Joint Preservation Society (ICRS) score, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), visual analog scale (VAS) for pain, and the subjective International Knee Documentation Committee (IKDC) score. Results: A total of 7 studies met inclusion criteria, including 385 patients undergoing injection of hUC-MSCs (mean age, 59.7 years). The mean follow-up was 23.4 months. Weighted averages of the WOMAC, macroscopic ICRS, subjective IKDC, and VAS scores all showed improvement from before to after treatment. No severe adverse reactions were recorded. Conclusion: Patients undergoing treatment of knee OA with hUC-MSCs might be expected to experience improvements in clinical outcomes. Additional high-quality randomized studies are needed to better determine the efficacy of hUC-MSC for the treatment of knee OA. [ABSTRACT FROM AUTHOR]

Incremental sheet forming (ISF) has demonstrated significant potential to form complex three-dimensional parts without using component-specific tools and is suitable for economically fabricating low-volume functional sheet metal parts. Single-point incremental forming (SPIF) uses only one tool to form components and requires additional setup to form complex geometries. Double-sided incremental forming (DSIF), using two tools (one on either side of the sheet), can form features from top and bottom of sheet in single setup. While forming components with multiple features, the accuracy of component depends on the tool path strategy used for each feature and sequence in which features are formed. Methodologies are developed to recognise features from free-form components modeled using single and/or multiple surfaces. Recognised features are sliced using horizontal, inclined or offset strategies (developed during the present work) based on the geometrical characteristics of a given feature. Selection of best-forming sequence is automated based on the relation between features and process mechanics. Results presented in this paper show that complex free-form geometries can be formed with good accuracy using proposed methodologies. Maximum deviation between the measured and ideal profiles is less than 400 μm, while using right sequence and appropriate tool path strategy. [ABSTRACT FROM AUTHOR]

We report the first demonstration of optical detection by thermoelectric nanowire junctions. We employed devices composed of bismuth nanowire arrays which are capped with a transparent indium tin oxide electrode. The incident surface features very low optical reflectivity and enhanced light trapping. The unique attributes of the thermoelectric arrays are the combination of strong temporal and optical wavelength dependences of the photocurrent. Under infrared illumination, the signal can be completely described by thermoelectric effects considering cooling rates given by heat diffusion through the array. In addition, under visible illumination, we observe a photovoltaic response. [ABSTRACT FROM AUTHOR]