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Additive manufacturing (AM) offers potential solutions when conventional manufacturing reaches its technological limits. These include a high degree of design freedom, lightweight design, functional integration and rapid prototyping. In this paper, the authors show how AM can be implemented not only for prototyping but also production using different optimization approaches in design including topology optimization, support optimization and selection of part orientation and part consolidation. This paper aims to present how AM can reduce the production cost of complex components such as jet engine air manifold by optimizing the design. This case study also identifies a detailed feasibility analysis of the cost model for an air manifold of an Airbus jet engine using various strategies, such as computer numerical control machining, printing with standard support structures and support optimization.

Parameters that affect the production price of the air manifold such as machining, printing (process), feedstock, labor and post-processing costs were calculated and compared to find the best manufacturing strategy.

Results showed that AM can solve a range of problems and improve production by customization, rapid prototyping and geometrical freedom. This case study showed that 49%–58% of the cost is related to pre- and post-processing when using laser-based powder bed fusion to produce the air manifold. However, the cost of pre- and post-processing when using machining is 32%–35% of the total production costs. The results of this research can assist successful enterprises, such as aerospace, automotive and medical, in successfully turning toward AM technology.

Important factors such as validity, feasibility and limitations, pre-processing and monitoring, are discussed to show how a process chain can be controlled and run efficiently. Reproducibility of the process chain is debated to ensure the quality of mass production lines. Post-processing and qualification of the AM parts are also discussed to show how to satisfy the demands on standards (for surface quality and dimensional accuracy), safety, quality and certification. The original contribution of this paper is identifying the main production costs of complex components using both conventional and AM.

The purpose of this meta-analysis was to examine the effect of pomegranate juice (PJ) intake on glycemic control in adults.

Materials and methods: PubMed (Medline), ISI Web of Science, Cochrane Library and Scopus databases, measuring glucose and/or insulin and Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) in adults, were searched from inception to December 11, 2021. Moreover, to examine whether grouping factors influenced heterogeneity between research results, subgroup analysis was used.

This meta-analysis showed that PJ intake reduced HOMA-IR significantly, especially if =250 mL was used. This reducing effect remained significant in females, nondiabetic patients and unhealthy subjects.

The authors believe the presented data would be highly motivating and of a wide readership for the readers of your journal, and this paper stimulating a surge of research on the impact of PJ consumption on glycemic indices.

This paper aims to study numerically the non-Newtonian solution of carboxymethyl cellulose in water along with copper oxide nanoparticles, which flow turbulently through twisted smooth and finned tubes.

The twisted-tape inserts of rectangular and triangular sections are investigated under constant wall heat flux and the nanoparticle concentration varies between 0% and 1.5%. Computational fluid dynamics simulation is first validated by experimental information from two test cases, showing that the numerical results are in good agreement with previous studies. Here, the impact of nanoparticle concentration, tube twist and fins shape on the heat transfer and pressure loss of the system is measured. It is accomplished using longitudinal rectangular and triangular fins in a wide range of prominent parameters.

The results show that first, both the Nusselt number and friction factor increase with the rise in the concentration of nanoparticles and twist of the tube. Second, the trend is repeated by adding fins, but it is more intense in the triangular cases. The tube twist increases the Nusselt number up to 9%, 20% and 46% corresponding to smooth tube, rectangular and triangular fins, respectively. The most twisted tube with triangular fins and the highest value of concentration acquires the largest performance evaluation criterion at 1.3, 30% more efficient than the plain tube with 0% nanoparticle concentration.

This study explores an innovative approach to enhancing heat transfer in a non-Newtonian nanofluid flowing through an oval tube. The use of twisted-tape inserts with rectangular and triangular sections in this specific configuration represents a novel method to improve fluid flow characteristics and heat transfer efficiency. This study stands out for its originality in combining non-Newtonian fluid dynamics, nanofluid properties and geometric considerations to optimize heat transfer performance. The results of this work can be dramatically considered in advanced heat exchange applications.

This study aims to predict the behavior of donors to give to the health sector compared with other sectors in Shiraz city, South Iran, using the revised theory of planned behavior (TPB).

This was a descriptive-analytic cross-sectional study. A standard questionnaire, which comprising 32 items, was used to survey 277 donors affiliated with various charitable associations in the city of Shiraz, South of Iran, in 2018. Participants were selected using stratified sampling and simple random sampling techniques. The authors used a revised TPB, a general model to predict and explain behavior across various types of behaviors and predict behavior based on an individual’s attitudes and beliefs. This model was used to examine the influence of eight social-psychological variables (attitude, perceived behavioral control [PBC], subjective norm, descriptive norm, moral norm, past behavior, intention behavior, self-reported) on an individual’s intention to donate to health sector charity. Data was analyzed using SPSS software version 22.0.

The score of all constructs of TPB in the health sector was significantly higher than in the non-health sector (P < 0.001), except for the PBC. This indicates that it does not influence the donors’ behavioral intention in selecting of charitable activity domains (e.g. health and non-health). The constructs of the moral norm, descriptive norm and past behavior in the health sector donors; and the constructs of attitude, moral norms and the variables of the annual income, and work experience in the non-health sector donors were identified as significant predictors of donors’ intention behavior. Moreover, attitude, moral norm, descriptive norm, past behavior, male gender and the annual income were the significant predictors of donors’ intention to give to health charity initiatives.

One of the most important mechanisms to compensate for the shortage of resources of the health system is the use of donors’ participation capacity. However, different donors act differently in selecting charitable activity domains, including the health sector and non-health sector (e.g. school-building donors’ association, house-building donors’ association, city-building donors’ association, library-building donors’ association, etc.). To attract donors’ participation in the health sector, some interventions to change the behavioral intention of donors towards the health sector through constructs of TPB should be taken.