Welding is one of the major joining processes employed in fabrication industry, especially one that manufactures boiler, pressure vessels, marine structure etc. Control of weld quality is very important for such industries. In this work an attempt is made to correlate arc sound with the weld quality. The welding is done with various combinations of current, voltage, and travel speed to produce good welds as well as weld with defects. The defects considered in this study are lack of fusion and burn through. Raw data points captured from the arc sound were converted into amplitude signals. The welded specimens were inspected and classified into 3 classes such as good weld and weld with lack of fusion and burn through. Statistical features of raw data were extracted using data mining software. Using classification algorithms the defects are classified. Two algorithms namely, J48 and random forest were used and classification efficiencies of the algorithms were reported.

This study details the design and fabrication of woven electrospun nanotextile patches for vascular applications that meet the mechanical and biological requirements. Nanotextile vascular patches based on biodegradable polymers such as poly‐l‐lactic acid (PLLA) and poly(caprolactone)/collagen (PCL/Col) are fabricated by integrating the techniques of electrospinning and weaving. Fibrous polymeric nanoyarns obtained by electrospinning are strengthened via different postprocessing techniques of heat‐stretching and plying, to generate interwoven nanotextiles that are tightly packed, mechanically strong, yet flexible. The unique pattern of nanofibers within the nanotextile results in its exceptional anisotropic mechanical behavior, appropriate for a vascular patch material. Moreover, these matrices exhibit good hydrophilicity, protein adsorption, and hemocompatibility, when compared to the commercial controls such as expanded polytetrafluoroethylene (ePTFE) and polyethylene terephthalate (PET). Furthermore, endothelial cells adhered, spread, and proliferate well on the nanotextile. Thus, this study demonstrates that the unique nanofibrous architecture of woven textiles aids in developing a novel biodegradable material, which meets the clinical standards of a vascular patch.

The current COVID-19 pandemic situation has posed a significant threat to human health. This calls for versatile facemask filters with high filtration efficiency and biocidal activity. Herein, we have rationally designed a three-layered nanofilter mask consisting of electrospun polycaprolactone (PCL) and curcumin as a nanocoating on a polypropylene spunbond membrane. The nanomask thus developed had a particulate filtration efficiency of 96.8 ± 0.1%, with good breathability (64 ± 2 Pa) and a high quality factor (0.052 ± 0.0005 Pa–1) for a coating thickness of ∼20 μm. An aerosol filtration efficiency of >99.99% was achieved for both bacteria and bacteriophages (a virus surrogate). Curcumin loading into the nanocoating induced significant contact-killing efficiency against bacteria and bacteriophages, implying the high biocidal activity presented by the nanomask. Furthermore, this mask could be reused up to 30 times after successive washing and drying, without alterations in its particle-filtration efficiency or fibrous morphology. Thus, by adopting a simple, scalable technique, a nanomask with manifold features was developed that satisfies the essential demands of air filtration in the current pandemic era.

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Biomedical implants possessing the structural and functional characteristics of extracellular matrix (ECM) are pivotal for vascular applications. This study investigated the potential of recreating a natural ECM-like structural and functional environment on the surface of biodegradable polymeric nanotextiles for vascular implants. Human adipose-derived mesenchymal stem cells (MSCs) were grown on a suitably engineered polycaprolactone (PCL) nanofibrous textile and were allowed to modify its surface through the deposition of MSC-specific ECM. This surface-modified nanotextile showed mechanical characteristics and functionality appropriate for vascular patch material. The uniformity of ECM coating significantly improved the viability, proliferation, and migration of human endothelial cells compared to bare and xenogeneic collagen-coated PCL nanotextile patches. Thus, a polymeric nanotextile, which is surface modified using MSC-driven ECM, provided a rapid and improved endothelialization, thereby suggesting its potential for vascular patch applications.