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We introduce a second‐order accurate time‐marching pressure‐correction algorithm to accommodate weakly‐compressible highly‐viscous liquid flows at low Mach number. As the incompressible limit is approached (Ma ≈ 0), the consistency of the compressible scheme is highlighted in recovering equivalent incompressible solutions. In the viscous‐dominated regime of low Reynolds number (zone of interest), the algorithm treats the viscous part of the equations in a semi‐implicit form. Two discrete representations are proposed to interpolate density: a piecewise‐constant form with gradient recovery and a linear interpolation form, akin to that on pressure. Numerical performance is considered on a number of classical benchmark problems for highly viscous liquid flows to highlight consistency, accuracy and stability properties. Validation bears out the high quality of performance of both compressible flow implementations, at low to vanishing Mach number. Neither linear nor constant density interpolations schemes degrade the second‐order accuracy of the original incompressible fractional‐staged pressure‐correction scheme. The piecewise‐constant interpolation scheme is advocated as a viable method of choice, with its advantages of order retention, yet efficiency in implementation.

As a collective paradigm of leadership emerges in the literature, many community leadership programs still align with leader-centric perspectives. The Kansas Leadership Center’s Leadership Transformation Grant is an exemplar of developing collective leadership in the civic arena. The purpose of this article is twofold: (1) to present the findings of a community-engaged, qualitative research study on the impact of collective leadership development on the practice of civic leadership and (2) to discuss relevant implications learned from reflections on the methodology for the practice of community-engaged research.

This study is a form of engaged research (Van de Ven, 2007) and is consistent with the principles of community-based research (Strand, Marullo, Cutforth, Stoecker, & Donohue, 2003). I took an exploratory approach to this study because the knowledge intersection of collective leadership, civic leadership and leadership development is still emerging and understudied. I explored the individual, group and systems levels as three components of a complex adaptive system (Uhl-Bien, Marion, & McKelvey, 2007). To better understand the dynamic relationship between individual, group and system in this grant team, I employed a three-phase study including methods of deliberative civic engagement, open-ended survey and interview.

Findings illustrate the effectiveness of the grant program on developing a shared language and leadership framework and clarifying leadership goals for participants. Implications include the importance of collective leadership development opportunities that center adaptive challenges and convene participants across levels of leadership and sectors. Additionally, the findings highlight the need to consider authority, identity and culture as central components of the practice of leadership. Reflections on the community-engaged methodology demonstrate the value of learning about leadership practices from the community practitioners to inform community leadership development interventions. Implications include approaching research as iterative and pushing back on academic norms that provide tension in engaged work.

Little research crosses all three boundaries of collective leadership, leadership development and civic leadership literature. This intersection focuses on understanding how collective leadership can contribute to enhancing the practice of civic leadership. The current study is situated within this knowledge gap and explores (1) the experiences of members of a civic group who have (2) participated in leadership development that (3) aligns with a collective leadership paradigm and are (4) trying to make progress on an adaptive challenge.

Methylene blue (MB) is classified as a cationic dye which is widely used as chemical indicator, coloring agent and biological stain. The discharge of this dye to the water streams is harmful to the human beings. For this reason, this study investigated the removal of MB from aqueous solution by hydrogel nanocomposite.

In experimental part, at first, ultraviolet (UV)-curable hydrogel/chitosan nanocomposite, which improves its elasticity by urethane acrylate, was synthesized and characterized by FTIR and SEM analysis. Afterward, the synthesized hydrogel nanocomposite was applied for the removal of MB and the influence of operational condition including nanocomposite loading, dye concentration, contact time and pH of solution was specified. Moreover, isotherm studies as well as kinetics survey were performed.

Langmuir, Freundlich, Brunauer, Emmett and Teller and Tempkin adsorption isotherms were assessed for the analysis of experimental data indicating the Freundlich isotherm was the best fitted one. The adsorption kinetics data was examined indicating the adsorption kinetics appropriate to pseudo-second-order kinetics model.

The predominant water absorption property of the UV-curable hydrogel/chitosan nanocomposite to 8.5 steps and outstanding adsorption capacity for the elimination of MB on hydrogel nanocomposite subscribed that the synthesized hydrogel could be a favorable adsorbent for simultaneous absorption of water and removal of cationic dyes.

The article aims to provide an accurate and efficient numerical algorithm for viscous flows in power-law fluids under various thermal boundary and partial slip conditions.

We are conducting a numerical investigation using the Taylor–Galerkin/pressure correction finite element method, which builds upon the work of previous researchers. Here, attention is therefore given to the interplay of various thermal boundary and stick-slip conditions and their impact on non-isothermal inelastic fluid.

The results demonstrate the influence of the Prandtl, Brinkman and Reynolds numbers on the flow’s thermal and hydrodynamic behavior, concentrating on the impact of slip at the wall. Furthermore, we have presented the effects of these dimensionless parameters on the detailed local and average Nusselt numbers, illustrated the high accuracy we obtained for numerical convergence, and compared our results with those of previous papers, observing excellent agreement.

We have successfully tested the code under the presented industrial conditions. Future research directions on this topic aim for efficient and robust solvers for non-Newtonian thermal rheological models; this algorithm can be used for that purpose.

This algorithm has never been used for numerical analysis of such a problem previously.

Acrylonitrile butadiene styrene is an important material in 3D printing due to its strength, durability, heat resistance and cost-effectiveness. These properties make it suitable for various applications, from functional prototypes to end-use products. This study aims to model and predict the mechanical properties of acrylonitrile butadiene styrene parts produced using the fused deposition modeling process.

The experiment was carefully designed to determine the optimal print parameters, including layer thickness, nozzle temperature and infill density. Tensile tests were performed on all printed samples following industry standards to gauge the mechanical properties such as elastic modulus, ultimate tensile strength, yield strength and breakpoint. Taguchi optimization and variable analysis were used to explore the relationship between mechanical properties and print parameters. Furthermore, an artificial neural network (ANN) regression model was implemented to predict mechanical properties based on varying print conditions.

The results demonstrated that layer thickness has the most significant influence on mechanical properties when compared to other print conditions. The optimization approaches indicated a clear relationship between the selected print parameters and the material’s mechanical response. For acrylonitrile butadiene styrene material, the optimal print settings were determined to be a 0.25 mm layer thickness, a 270 °C nozzle temperature and a 30 % infill density. Moreover, the ANN model notably excelled in predicting the yield strength of the material with greater accuracy than other mechanical properties.

Comparing the accuracy and capabilities of the Taguchi and ANN models in analyzing mechanical properties, it was found that both models closely matched the experimental data. However, the ANN model showed superior accuracy in predicting tensile outcomes. In conclusion, while the ANN model offers higher predictive accuracy for tensile results, both Taguchi and ANN methods are effective in modeling the mechanical properties of 3D-printed acrylonitrile butadiene styrene materials.

The purpose of this study was to analyze the influence of epichlorohydrin (ECH) concentration and reaction time on the food-grade resistant starch production and its pasting properties by using native cassava starch of Misiones-Argentina origin.

Cassava starch was modified using ECH (0.30 and 0.15 per cent) during 4 or 8 h. Digestibility was evaluated by determining resistant starch as total dietary fiber. Pasting properties and the cross-linking degree were studied using a micro-viscoamylograph (Brabender).

Resistant starch content was not influenced by ECH concentration and reaction time. Cross-linking was detected at higher reaction times (8 h) and ECH concentrations (0.30 per cent), where a decrease in viscosity peaks by more than 80 per cent was observed. Both pasting temperature and breakdown were increased, whereas a decrease in retrogradation was detected.

Starches can be suitable for different food applications. This is because of the ability to modify its pasting properties and the invariability of the in vitro digestibility of cassava starch as a result of using ECH (at concentrations approved by local and regional legislation) and reaction times of 4 and 8 h.

Information related to the modification of cassava starch using ECH is scarce or not available nowadays in literature.

Resistant starch, defined as all starch and starch-degradation products not absorbed by small intestine of healthy individuals, is included in the diet of individuals due to its prebiotic characteristics and protective effects against diseases like colon cancer, type II diabetes, obesity and cardiovascular diseases. Some cooking methods are known as effective on resistant starch content of foods. The purpose of this paper is to explore the effect of various cooking methods on resistant starch content of foods.

Potential health benefits and functional features of the resistant starch have been emphasized in the recent years. This review includes up-to-date scientific findings in different studies on the effect of various cooking methods on resistant starch content of foods. Advantages and nutritional quality of resistant starch are included to topic.

Cooking methods including baking, steaming and autoclave cooking increased the amount of the resistant starch of foods, but cooking method such as pressure cooking decreased the amount of the resistant starch of foods. Boiling, frying, microwave cooking and extrusion cooking have the potential of increasing the amount of resistant starch, which depends on the source of starch and the process conditions. Although frying method has a high potential to increase the resistant starch content of foods, it is inconvenient to recommend frying to modify resistant starch content of foods due to detrimental effects of frying and products on health.

This paper focuses on the effects of various cooking methods on resistant starch content of foods, which offers a promising future for the inartificial development of the prebiotic content of diet. Due to its potential health benefits, appropriate cooking methods should be preferred to increase resistant starch content of foods.

The enrichment of bread with non-digestible prebiotic ingredients may exert health-promoting effects and provide healthier food choices for those suffering from metabolic diseases, including obesity and diabetes. The purpose of this study was to investigate the effects of ß-glucan and resistant starch incorporation on the glycemic index (GI) and glycemic load (GL) of white bread.

Seven different formulations of prebiotic bread were produced using different proportions of ß-glucan (0.8, 1 and 1.2 per cent), resistant starch (5.5, 8 and 10.5 per cent) and the combination of resistant starch and ß-glucan in a ratio of 4:0.5.

The GI and GL of the prebiotic bread prepared with 1 per cent ß-glucan (w/w) were 55.7 and 7.8, respectively, whereas those of the prebiotic bread prepared with 8 per cent resistant starch (w/w) were 64.8 and 8.42, respectively, with both breads having significantly lower GI and GL values than the control (P < 0.05). It was concluded that the incorporation of 1 per cent ß-glucan may be beneficial in producing prebiotic bread with both low GI and low GL.

Although white bread is a main food source in human diet, its high GI and GL make it an unhealthy food choice. The incorporation of ingredients with prebiotic effects, such as ß-glucan and resistant starch, can improve the nutritional value of this product by lowering its GI and GL.