This study reports flexible nanocomposite-based piezoelectric nanogenerators (PENGs) fabricated by dispersing various piezoelectric nanoparticles (BaTiO3, ZnO, and PZT) and graphene nanopowder in a silicone matrix. The results indicated that the PZT-based composites showed superior performance in comparison to other ceramics. Subsequently, practical application of PENGs was demonstrated by developing a fully functioning shoe-insole nanogenerator (SING). The SING generated high open-circuit voltage (∼27 V), short-circuit current (429.23 μA), and power density (402 mW/m2) under real-time human walking. Moreover, a facile and inexpensive fabrication method for efficient, skin-friendly, and highly stretchable biomechanical piezoelectric sensors is also proposed. In this regard, multiwall carbon nanotubes/silicone composite stretchable electrodes were prepared to be compatible with the sensors. The electrodes displayed stability even under high uniaxial elongation (100%), and the fabricated sensors responded effectively to almost every joint movement. The results suggested that the fabricated PENGs can be potentially used as self-powered biomechanical energy harvesters/sensors in wearable electronics, haptic sensing, or internet of human-related applications.

Fuzzy logic image analysis techniques were used to analyze three shades of blue (lavender blue, light blue, and dark blue) in dermoscopic images for melanoma detection. A logistic regression model provided up to 82.7% accuracy for melanoma discrimination for 866 images. With a support vector machines (SVM) classifier, lower accuracy was obtained for individual shades (79.9–80.1%) compared with up to 81.4% accuracy with multiple shades. All fuzzy blue logic alpha cuts scored higher than the crisp case. Fuzzy logic techniques applied to multiple shades of blue can assist in melanoma detection. These vector-based fuzzy logic techniques can be extended to other image analysis problems involving multiple colors or color shades.

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Flexible electronic devices have gained significant interest due to their different potential applications. Herein, we report highly flexible, stretchable, and sensitive sensors made of sprayed CNT layer, sandwiched between two polymer layers. A facile fabrication process was employed in which the CNT solution was directly sprayed onto a patterned bottom polymer layer, above which a second polymer layer was casted to get a sandwiched composite structure. Varying amounts of CNT solution (i.e., 10, 25, 40, 70, and 100 mL) were sprayed to get conductive CNT layers of different thicknesses/densities. The physical characteristics of the conductive CNT layers were studied through SEM and optical images. The starting electrical resistance values (without strain) as well as the changes in electrical resistance against human body motions were monitored. The synthesized samples exhibited good response against finger and wrist bending. The conductivity of the samples increased with increase of CNT solution volume while the sensitivity followed the inverse relation, suggesting that the sensors with controlled sensitivity could be fabricated for targeted strain ranges using the proposed method.

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INTRODUCTION: Colonoscopy is the most commonly used method for colon cancer screening. The quality of prep greatly affects the examination. Risk factors for inadequate prep include prior inadequate prep, male gender, prior surgery, diabetes, low health literacy and cognitive delay. Studies have shown improvement in colonoscopy prep using split-dosing however despite this, inadequate prep continues to be a problem. One solution at our institution is to hospitalize selected patients with prior failed outpatient colonoscopy prep in an attempt to improve the prep quality. METHODS: We retrospectively identified all patients who were hospitalized for colonoscopy prep from 2016 to 2018. Patients who did not have documentation of prep quality were excluded. Data including age, gender, indication for procedure and presence of risk factors was gathered. The prior prep quality and prep quality after admission was documented. RESULTS: 122 patients were included in the study. “Screening” was the most common indication for the procedure. Most of the patients had at least one risk factor for inadequate prep. 90 patients had improvement in their prep quality. CONCLUSION: Bowel prep continues to be inadequate in up to 25% of examinations. Several patient related risk factors for inadequate prep have been identified in previous studies. Patients who have risk factors for slow bowel transit such as immobility, CVA and chronic use of narcotics can also be factors in colon prep. We believe the improvement in bowel prep in our study is related to adherence to dietary restrictions, accurate laxative consumption, and improved assessment of stool clearance. Our study also showed a significant number of improved bowel prep quality in patients who had risk factors for poor prep. The cost of hospitalization was not evaluated in our study. We believe that an adequate bowel would result in a longer time-interval for subsequent colonoscopies and reduced overall cost. Our study is limited given its retrospective design and small number of patients. In addition, given that our software does not allow use of the Boston Bowel Prep Scale, the results may be difficult to generalize to other populations. Repeat studies would be needed to assess cost effectiveness. Quality of bowel prep continues to be a barrier to high quality colonoscopy. This study shows that hospitalized bowel prep may help improve prep quality in a select group of patients in the underserved population and with known risk factors.