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Since spatially offset Raman spectroscopy (SORS) can acquire biochemical measurements of tissue quality through light scattering materials, we investigated the feasibility of this technique to acquire Raman bands related to the fracture resistance of bone. Designed to maximize signals at different offsets, a SORS probe was used to acquire spectra from cadaveric bone with and without skin-like tissue phantoms attenuating the light. Autoclaving the lateral side of femur mid-shafts from 5 female and 5 male donors at 100 °C and again at 120 °C reduced the yield stress of cortical beams subjected to three-point bending. It did not affect the volumetric bone mineral density or porosity. Without tissue phantoms, autoclaving affected more Raman characteristics of the organic matrix when determined by peak intensity ratios, but fewer matrix properties depended on the three offsets (5 mm, 6 mm, and 7 mm) when determined by band area ratios. The cut-off in the thickness of the tissue phantom layers was ∼4 mm for most properties, irrespective of offset. Matching trends when spectra were acquired without phantom layers between bone and the probe, ν 1 PO 4 3- /Amide III and ν 1 PO 4 3- /(proline + OH-proline) were higher and lower in the non-treated bone than in the autoclaved bone, respectively, when the thickness of tissue phantom layers was 4 mm. The layers, however, caused a loss of sensitivity to autoclaving-related changes in ν 3 CO 3 /ν 1 PO 4 3- and crystallinity. Without advanced post-processing of Raman spectra, SORS acquisition through turbid layers can detect changes in Raman properties of bone that accompany a loss in bone strength., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Jeffry S Nyman reports financial support and equipment, drugs, or supplies were provided by National Institute of Arthritis and Musculoskeletal and Skin Diseases. Jeffry S Nyman reports financial support and administrative support were provided by US Department of Veterans Affairs., (Published by Elsevier B.V.)

Diabetes mellitus (DM) is a general term for heterogeneous metabolic disorders whose main characteristic is chronic hyperglycemia. Considering that conventional diagnostic methods are currently unable of early DM detection and the number of diabetic patients has been increasing worldwide, there is a clinical need for novel diagnostic approaches. Fourier-transform infrared (FT-IR) spectroscopy technique an alternative non-invasive diagnostic method for real-time evaluation of biofluids such as saliva. This study aims evaluate the feasibility of diagnosing diabetes and periodontitis through saliva samples based on their FT-IR spectra. Our first collection and spectral analysis of samples was a pilot study and comprised a total of 23 patients, 2 healthy, 9 with diabetes and 12 with diabetes and periodontitis. By using weighted KNN as classifier, we have obtained an area under the Receiver Operating Characteristic curve of 0.92 and 0.95 when considering the diabetes or diabetes + periodontitis groups as positive groups, respectively., Competing Interests: Declaration of Competing Interest The authors declare no financial or commercial conflict of interest., (Copyright © 2022. Published by Elsevier B.V.)

This paper presents an inherent speed estimation scheme associated to the Indirect Field Oriented Control in case of Induction motor sensorless control. Indeed, through the design of a Multiobjective Adaptive Fuzzy Luenberger Observer, the speed sensorless control issue even at low speed, the observer poles' assignment issues and the speed estimation's sensitivity to rotor resistance uncertainties issue are treated concurrently. First of all, the structure of the proposed Takagi-Sugeno adaptive observer is described. Secondly, based on Lyapunov theory, observer gains are designed and a fuzzy speed estimation scheme is provided. The design's objectives consist of minimizing the sensitivity of the proposed observer to rotor resistance uncertainties (using the L 2 techniques) and to guarantee a specified observer dynamic performances through a D-stability analysis. The design conditions are formulated into Linear Matrix Inequalities terms. Finally, experiments are conducted to demonstrate the effectiveness of the proposed results regardless of uncertainties in the rotor resistance., (Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.)

Controlling the cell-substrate interactions at the bio-interface is becoming an inherent element in the design of implantable devices. Modulation of cellular adhesion in vitro, through topographical cues, is a well-documented process that offers control over subsequent cellular functions. However, it is still unclear whether surface topography can be translated into a clinically functional response in vivo at the tissue/device interface. Herein, we demonstrated that anisotropic substrates with a groove depth of ∼317nm and ∼1988nm promoted human tenocyte alignment parallel to the underlying topography in vitro. However, the rigid poly(lactic-co-glycolic acid) substrates used in this study upregulated the expression of chondrogenic and osteogenic genes, indicating possible tenocyte trans-differentiation. Of significant importance is that none of the topographies assessed (∼37nm, ∼317nm and ∼1988nm groove depth) induced extracellular matrix orientation parallel to the substrate orientation in a rat patellar tendon model. These data indicate that two-dimensional imprinting technologies are useful tools for in vitro cell phenotype maintenance, rather than for organised neotissue formation in vivo, should multifactorial approaches that consider both surface topography and substrate rigidity be established., Statement of Significance: Herein, we ventured to assess the influence of parallel groves, ranging from nano- to micro-level, on tenocytes response in vitro and on host response using a tendon and a subcutaneous model. In vitro analysis indicates that anisotropically ordered micro-scale grooves, as opposed to nano-scale grooves, maintain physiological cell morphology. The rather rigid PLGA substrates appeared to induce trans-differentiation towards chondrogenic and/or steogenic lineage, as evidence by TILDA gene analysis. In vivo data in both tendon and subcutaneous models indicate that none of the substrates induced bidirectional host cell and tissue growth. Collective, these observations indicate that two-dimensional imprinting technologies are useful tools for in vitro cell phenotype maintenance, rather than for directional neotissue formation, should multifactorial approaches that consider both surface topography and substrate rigidity be established., (Copyright © 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)