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Everyone is extremely concerned about environmental protection and health safety due to the rise in living standards. Plant-derived natural dyes have garnered much industrial attention in food, pharmaceutical, textile, cosmetics, etc. owing to their health and environmental benefits. The present study aims to focus on the elimination of the use of synthetic dyes and provides brief information about natural dyes, their sources, extraction procedures with characterization and various advantages and disadvantages.

In producing natural colors, extraction and purification are essential steps. Various conventional methods used till date have a low yield, as these consume a lot of solvent volume, time, labor and energy or may destroy the coloring behavior of the actual molecules. The establishment of proper characterization and certification protocols for natural dyes would improve the yielding of natural dyes and benefit both producers and users.

However, scientists have found modern extraction methods to obtain maximum color yield. They are also modifying the fabric surface to appraise its uptake behavior of color. Various extraction techniques such as solvent, aqueous, enzymatic and fermentation and extraction with microwave or ultrasonic energy, supercritical fluid extraction and alkaline or acid extraction are currently available for these natural dyes and are summarized in the present review article.

If natural dye availability can be increased by the different extraction measures and the cost of purified dyes can be brought down with a proper certification mechanism, there is a wide scope for the adoption of these dyes by small-scale dyeing units.

This study draws on insights from the theory of conservation of resources to explore the impact of servant leadership (SL), creative adaptability (CA), and psychological well-being (PWB) on the service recovery performance (SRP) of employees. More specifically, the objective of this study is twofold: one to ascertain whether employees' service recovery performance would increase significantly after their exposure to SL, and two, to determine whether CA and PWB serially mediate the link between SL and SRP.

To analyze the data collected from a sample of 371 air service providers’ front-line employees (FLEs), partial least squares structural equation modeling (PLS-SEM) was performed.

The result indicated that SL was positively related to SRP. Likewise, the results of the serial mediation analysis showed that CA and PWB independently and serially mediated the SL-SRP relationship. This study makes significant contributions to the literature on SL and SRP.

This study adds to the growing body of research on how FLEs effectively deal with customers who are dissatisfied with their service failure experiences. Specifically, this research expands on previous results by proving the favorable effect of leadership style on FLE’s service recovery performance. In addition, the current study examines how effective service recovery is by assessing the employee’s resources based on COR theory. Finally, this research provides new insight into the influence of SL on SRP through the serial mediation of CA and FLE’s well-being.

The present work is devoted to investigating the sensitivity analysis of the electroosmotic peristaltic motion of non-Newtonian Casson fluid with the effect of the chemical reaction and magnetohydrodynamics through the porous medium. The main focus is on flow efficiency quantities such as pressure rise per wavelength, frictional forces on the upper wall and frictional forces on the lower wall. This initiative is to bridge the existing gap in the available literature.

The governing equations of the problem are mathematically formulated and subsequently simplified for sensitivity analysis under the assumptions of a long wavelength and a small Reynolds number. The simplified equations take the form of coupled nonlinear differential equations, which are solved using the built-in Matlab routine bvp4c. The response surface methodology and artificial neural networks are used to develop the empirical model for pressure rise per wavelength, frictional forces on the upper wall and frictional forces on the lower wall.

The empirical model demonstrates an excellent fit with a coefficient of determination reaching 100% for responses, frictional forces on the upper wall and frictional forces on the lower wall and 99.99% for response, for pressure rise per wavelength. It is revealed through the sensitivity analysis that pressure rise per wavelength, frictional forces on the upper wall and frictional forces on the lower wall are most sensitive to the permeability parameter at all levels.

The objective of this study is to use artificial neural networks simulation and analyze the sensitivity of electroosmotic peristaltic motion of non-Newtonian fluid with the effect of chemical reaction.