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"Nanocellulose" have captivated the topical sphere of sturdily escalating market for sustainable materials. The review focuses on the comprehensive understanding of the distinct surface chemistry and functionalities pertaining to the renovation of macro-cellulose at nanodimensional scale to provide an intuition of their processing-structure-function prospective. The abundant availability, cost effectiveness and diverse properties associated with plant-based resources have great economical perspective for developing sustainable cellulose nanomaterials. Hence, emphasis has been given on nanocellulose types obtained from plant-based sources. An overarching goal is to provide the recent advancement in the preparation routes of nanocellulose. Considering the excellent shear thinning/thixotropic/gel-like behavior, the review provids an assemblage of publications specifically dealing with its application as rheology modifier with emphasis on its use as bioink for 3D bioprinting for various biomedical applications. Altogether, this review has been oriented in a way to collocate a collective data starting from the historical perspective of cellulose discovery to modern cellulosic chemistry and its renovation as nanocellulose with recent technological hype for broad spanning applications., (Copyright © 2020 Elsevier B.V. All rights reserved.)

This study evaluated the flow properties of viscosity and flow rate for water and two common pediatric liquids. The flow properties of the test liquids are of interest to create a cup simulation model and "smart" prototype training cup. Two objective methods of determining flow properties were utilized: a rheometer to assess viscosity and a modified version of the International Dysphagia Diet Standardization Initiative (IDDSI) to assess flow rate. Rheometer results concluded that the pediatric supplements were less than 50 cP at all shear rates evaluated and exhibited shear-thinning properties, placing both liquids into the "thin" category. The IDDSI, which was performed according to standardized protocol and also with experimental modifications of varying syringe volumes, determined that all three test liquids had greater than 1 mL/s flow rate across all syringe types/sizes. The experimental modification of the IDDSI with 60 mL syringe volume was found to be the most consistent and applicable with discrete values obtained across all liquids tested. A flow rate factor equation can be determined with the use of a 60 mL syringe, with our laboratory setup, to create the cup simulation model. This computer-generated cup simulation model also aims to integrate engineering with clinical practice to develop a "smart" prototype training cup equipped with software to control flow rate.

Nanotechnology has become relevant in the food-related industries, and edible mushrooms can be a potential raw material for providing satisfied edible nanomaterial. In this study, by following 3 different pretreatments (hot water or cold alkali or hot alkali) insoluble polysaccharide nanoparticles were prepared from Flammulina velutipes by wet milling and high pressure homogenization and their properties were investigated. The resultant nanoparticles were characterized by SEM, GC-MS (for its main compositions), FTIR, XRD, and TG. The 1 wt% nanoparticle dispersions presented non-Newtonian, shear-thinning fluids with the viscosity in an increasing order for the hot water < cold alkali < hot alkali. Moreover, the dynamical rheological results showed differences of storage (G') and loss (G″) moduli of these particle dispersions. It was concluded that the Flammulina velutipes-derived polysaccharides nanoparticles have great potential applications in the food industry, for example, as emulsifiers, reinforcement agents, and bioactive carriers., (© 2017 Institute of Food Technologists®.)

Incorporation of nanofillers into a polymeric matrix has received much attention as a route to reinforced polymer nanocomposites. In the present work, an environmentally friendly chitosan (CTS)/titanium dioxide (TiO2) nanocomposite coating was designed/prepared and subsequently employed for imparting antibacterium and improved mechanical properties to cellulosic paper via surface coating. Effect of TiO2 nanoparticle loadings on the rheological behavior of nanocomposite coatings was investigated. Surface application of CTS/TiO2 nanocomposite coatings to cellulosic paper was performed, and the antibacterial activity and mechanical properties of surface-coated cellulosic paper were examined. Results showed that the increased TiO2 nanoparticle loadings decreased the viscosity and dynamic viscoelasticity of the as-prepared coatings, and improved the antibacterial activity and mechanical properties of surface-coated cellulosic paper. The optimum loading of TiO2 nanoparticles was identified at 10%. This work suggested that CTS/TiO2 nanocomposite coatings may have the potential to be used as a promising antibacterial protective coating for paper packaging., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Cellulose nanofibrils (CNFs) are produced and commonly used in the form of aqueous suspensions or gels. A number of studies have focused lately on rheological properties of CNF suspensions, which gives insight into properties of such materials and can reflect their behavior during handling. This Review summarizes the recent progress in rheological studies on CNF aqueous suspensions using rotational rheometry. Here, we discuss linear viscoelastic properties, i.e., frequency-dependent storage and loss moduli; shear flow behavior, i.e., apparent viscosity and shear stress as a function of shear rate; local flow characteristics, etc. In this Review, we point out that the rheological behavior of at least two types of CNF suspensions should be distinguished: (i) ones produced using mechanical fibrillation with or without enzymatic pretreatment (no surface chemical modification), which possess highly flocculated structure, and (ii) ones produced involving chemical modification pretreatments, e.g., carboxylation, carboxymethylation, quaternization, or sulfonation, which possess better colloidal stability and do not evidently flocculate.

Objective: Modeling of human liver development, especially cellular organization and the mechanisms underlying it, is fundamental for studying liver organogenesis and congenital diseases, yet there are no reliable models that mimic these processes ex vivo., Design: Using an organ engineering approach and relevant cell lines, we designed a perfusion system that delivers discrete mechanical forces inside an acellular liver extracellular matrix scaffold to study the effects of mechanical stimulation in hepatic tissue organization., Results: We observed a fluid flow rate-dependent response in cell distribution within the liver scaffold. Next, we determined the role of nitric oxide (NO) as a mediator of fluid flow effects on endothelial cells. We observed impairment of both neovascularization and liver tissue organization in the presence of selective inhibition of endothelial NO synthase. Similar results were observed in bioengineered livers grown under static conditions., Conclusion: Overall, we were able to unveil the potential central role of discrete mechanical stimulation through the NO pathway in the revascularization and cellular organization of a bioengineered liver. Last, we propose that this organ bioengineering platform can contribute significantly to the identification of physiological mechanisms of liver organogenesis and regeneration and improve our ability to bioengineer livers for transplantation.

The rheological behaviour of the nanocomposites based on chitosan (CS) and unmodified rectorite (REC) were first evaluated. The nanocomposites showed a low shear-rate non-Newtonian viscosity and a rapid shear-thinning behaviour. The zero shear rate viscosity and the storage and loss moduli for the nanocomposites displayed a monotonic increase with increasing REC content in comparison with pure CS. The results implied the presence of electrostatic and hydrogen-bonding interaction between CS and REC, which was corroborated by the SEM images and FT-IR analysis. Then CS beads and CS/REC nanocomposite beads were prepared via the cross-linking interaction of sodium tripolyphosphate and CS, SEM images indicated that the nanocomposite beads had more compact surface and internal structure than those of CS beads. The swelling degree of the nanocomposite beads in 0.9% (w/v) saline was only about 15%, while that of CS beads was 30%. The nanocomposite beads released the drug continuously; in the given 6 days the minimum cumulative release only reached 51.4%, much lower than that of pure CS beads (72.1%). Therefore, CS/REC nanocomposites are more suitable to apply as drug carrier than pure CS.