Early detection of oral cancer necessitates a minimally invasive, tissue-specific diagnostic tool that facilitates screening/surveillance. Brush biopsy, though minimally invasive, demands skilled cyto-pathologist expertise. In this study, we explored the clinical utility/efficacy of a tele-cytology system in combination with Artificial Neural Network (ANN) based risk-stratification model for early detection of oral potentially malignant (OPML)/malignant lesion. A portable, automated tablet-based tele-cytology platform capable of digitization of cytology slides was evaluated for its efficacy in the detection of OPML/malignant lesions (n = 82) in comparison with conventional cytology and histology. Then, an image pre-processing algorithm was established to segregate cells, ANN was trained with images (n = 11,981) and a risk-stratification model developed. The specificity, sensitivity and accuracy of platform/ stratification model were computed, and agreement was examined using Kappa statistics. The tele-cytology platform, Cellscope, showed an overall accuracy of 84–86% with no difference between tele-cytology and conventional cytology in detection of oral lesions (kappa, 0.67–0.72). However, OPML could be detected with low sensitivity (18%) in accordance with the limitations of conventional cytology. The integration of image processing and development of an ANN-based risk stratification model improved the detection sensitivity of malignant lesions (93%) and high grade OPML (73%), thereby increasing the overall accuracy by 30%. Tele-cytology integrated with the risk stratification model, a novel strategy established in this study, can be an invaluable Point-of-Care (PoC) tool for early detection/screening in oral cancer. This study hence establishes the applicability of tele-cytology for accurate, remote diagnosis and use of automated ANN-based analysis in improving its efficacy.

Oral cancer is the most common type of cancer among men in India and other countries in South Asia. Late diagnosis contributes significantly to this mortality, highlighting the need for effective and specific point-of-care diagnostic tools. The same regions with high prevalence of oral cancer have seen extensive growth in mobile phone infrastructure, which enables widespread access to telemedicine services. In this work, we describe the evaluation of an automated tablet-based mobile microscope as an adjunct for telemedicine-based oral cancer screening in India. Brush biopsy, a minimally invasive sampling technique was combined with a simplified staining protocol and a tablet-based mobile microscope to facilitate local collection of digital images and remote evaluation of the images by clinicians. The tablet-based mobile microscope (CellScope device) combines an iPad Mini with collection optics, LED illumination and Bluetooth-controlled motors to scan a slide specimen and capture high-resolution images of stained brush biopsy samples. Researchers at the Mazumdar Shaw Medical Foundation (MSMF) in Bangalore, India used the instrument to collect and send randomly selected images of each slide for telepathology review. Evaluation of the concordance between gold standard histology, conventional microscopy cytology, and remote pathologist review of the images was performed as part of a pilot study of mobile microscopy as a screening tool for oral cancer. Results indicated that the instrument successfully collected images of sufficient quality to enable remote diagnoses that show concordance with existing techniques. Further studies will evaluate the effectiveness of oral cancer screening with mobile microscopy by minimally trained technicians in low-resource settings.

A simplified model for studying the behavior of plain woven fabrics is presented. The model consists of two plate elements including a thin layer of matrix between them. Hierarchic shape functions are employed to characterize the initially curved profile of the yarns and the displacements of the plate elements. The plate model is used in conjunction with a simple micro-model which accounts for the material nonlinear response and damage of the yams. The behavior of plain woven fabrics under inplane tension, compression and inplane shear is examined. The plate-micro model combination is shown to be able to predict the important features of plain woven fabric response adequately. Predictions of the strength of plain woven fabrics using the plate model are compared with 3-D finite element analysis (FEA) results and currently available experimental/analytical results.

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The behavior of plain woven fabric composites is studied using three-dimensional finite elements which allows detailed modeling of the geometric complexities and spatial material variations within the fabric. Damages in the composite constituents viz. yarn and pure matrix are modeled on a continuum basis and related to their material constitutive behavior. The 3D constitutive laws describing pure matrix and yarn behavior are developed using a damage mechanics based approach with the dissipated energy density as the damage parameter. The strain energy dissipation (SED) concept is employed to describe the damage state and current stiffnesses of the weave constituents. A progressive failure analysis of plain woven fabrics subjected to tension and in-plane shear is carried out considering both geometric and material nonlinearities. The initiation and progression of damage within the fabric is investigated and the significant damage mechanisms outlined.Keywords: Woven composites, finite element analysis, damage mechanics, constitutive laws, failure INTRODUCTIONMicromechanics of textile composites has been the focus of study by many investigators [1][2][3][4][5][6][7][8][9][10][11]. The proper description of the internal weave geometry and spatial variation in material properties within the fabric presents a formidable task in the analysis of such composites. Most of the analytical studies on such composites have focussed on predicting their elastic properties [1][2][3][4][5][6][7]. Studies relating to prediction of their strength and failure modes are relatively few [8][9][10][11].A detailed study of the significant stresses and strains developed within the fabric and possible damage mechanisms can be accomplished by the use of three-dimensional finite elements. Nonlinear material behavior of composites is due to damage accumulation, which causes changes in the stiffnesses of the material. It is well known that macroscopic failure is preceded by an accumulation of different types of microscopic damage and stiffness losses due to the accumulation of such damage, which cause significant load Existing FE modeling tools and preprocessors are not adequate for rapidly creating complex 3-dimensional models needed for the purpose. Therefore, mesh generation programs were developed which would easily interface with a general purpose FEA software, ABAQUS [12]. FE models can be generated for plain weaves and higher-order satin-weaves using a minimal definition of the textile architecture. In the present approach, damages in the composite constituents are modeled on a continuum basis and related to the material constitutive behavior. The 3D constitutive laws describing matrix and yarn behavior are developed using a damage mechanics based approach, with the dissipated energy density as the damage parameter. The strain energy dissipation (SED) concept is employed to describe the damage state and current stiffnesses of the weave constituents. The yarns are treated as transversely isotropic while the pure matrix pockets are assumed ...

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